Baffour-Awuah, Nana Yaa; Fleet, Sarah; Baker, Susan S.; Butler, Johannah L.; Campbell, Catarina; Tischfield, Samuel; Mitchell, Paul D.; Moon, Jennifer E.; Allende-Richter, Sophie; Fishman, Laurie; Bousvaros, Athos; Fox, Victor; Kuokkanen, Mikko; Montgomery, Robert K.; Grand, Richard J.; Hirschhorn, Joel N.
2014-01-01
Objectives Recent data from mainly homogeneous European and African populations implicate a 140 bp region 5′ to the transcriptional start site of LCT (the lactase gene) as a regulatory site for lactase persistence and non-persistence. As there are no studies of United States non-homogeneous populations, we performed genotype/phenotype analysis of the -13910 and -22018 LCT SNPs in New England children, mostly of European ancestry. Methods Duodenal biopsies were processed for disaccharidase activities, RNA quantification by RT-PCR, allelic expression ratios by PCR, and genotyping and SNP analysis. Results were compared to clinical information. Results Lactase activity and mRNA levels, as well as sucrase-to-lactase ratios of enzyme activity and mRNA, showed robust correlations with genotype. None of the other LCT SNPs showed as strong a correlation with enzyme or mRNA activities as did -13910. Data were consistent with the -13910 being the causal sequence variant rather than -22018. Four individuals heterozygous for -13910T/C had allelic expression patterns similar to individuals with -13910C/C genotypes; of these, 2 showed equal LCT expression from the 2 alleles and a novel variant (-13909C>A) associated with lactase persistence. Conclusion The identification of -13910C/C genotype is very likely to predict lactase non-persistence, consistent with prior published studies. A -13910T/T genotype will frequently, but not perfectly, predict lactase persistence in this mixed European-ancestry population; a -13910T/C genotype will not predict the phenotype. A long, rare haplotype in 2 individuals with -13910T/C genotype but equal allele-specific expression contains a novel lactase persistence allele present at -13909. PMID:25625576
Akgül, Gülfirde; Della Casa, Philippe; Rühli, Frank; Warinner, Christina
2014-01-01
Ruminant milk and dairy products are important food resources in many European, African, and Middle Eastern societies. These regions are also associated with derived genetic variants for lactase persistence. In mammals, lactase, the enzyme that hydrolyzes the milk sugar lactose, is normally down-regulated after weaning, but at least five human populations around the world have independently evolved mutations regulating the expression of the lactase-phlorizin-hydrolase gene. These mutations result in a dominant lactase persistence phenotype and continued lactase tolerance in adulthood. A single nucleotide polymorphism (SNP) at C/T-13910 is responsible for most lactase persistence in European populations, but when and where the T-13910 polymorphism originated and the evolutionary processes by which it rose to high frequency in Europe have been the subject of strong debate. A history of dairying is presumed to be a prerequisite, but archaeological evidence is lacking. In this study, DNA was extracted from the dentine of 36 individuals excavated at a medieval cemetery in Dalheim, Germany. Eighteen individuals were successfully genotyped for the C/T-13910 SNP by molecular cloning and sequencing, of which 13 (72%) exhibited a European lactase persistence genotype: 44% CT, 28% TT. Previous ancient DNA-based studies found that lactase persistence genotypes fall below detection levels in most regions of Neolithic Europe. Our research shows that by AD 1200, lactase persistence frequency had risen to over 70% in this community in western Central Europe. Given that lactase persistence genotype frequency in present-day Germany and Austria is estimated at 71–80%, our results suggest that genetic lactase persistence likely reached modern levels before the historic population declines associated with the Black Death, thus excluding plague-associated evolutionary forces in the rise of lactase persistence in this region. This new evidence sheds light on the dynamic evolutionary history of the European lactase persistence trait and its global cultural implications. PMID:24465990
Lactase persistence versus lactose intolerance: Is there an intermediate phenotype?
Dzialanski, Zbigniew; Barany, Michael; Engfeldt, Peter; Magnuson, Anders; Olsson, Lovisa A; Nilsson, Torbjörn K
2016-02-01
According to the prevailing theory about the genetic background to lactose intolerance, there are three genotypes but only two adult physiological phenotypes: lactase persistence in individuals with the CT and TT genotypes and lactase non-persistence in individuals with the CC genotype. However, analysis of lactase activity from intestinal biopsies has revealed three distinct levels of activity, suggesting that an intermediate physiological phenotype may exist. To assess possible disparities between different genotypes with regard to biomarkers of lactase activity and physical symptoms during an oral lactose load test. A retrospective study using an oral lactose load test (n=487). Concentrations of hydrogen in exhaled air and blood glucose were measured. Afterwards, subjects were asked to provide oral mucosa samples for genotyping and answer a questionnaire (participation rate 56%, n=274). Mean hydrogen levels in exhaled air at 120min were significantly higher in the CT genotype than in the TT genotype. There was no significant difference in blood glucose levels between the two groups. Reported symptoms, with the possible exception of abdominal pain, were equally prevalent in both groups. Subjects with the CT and TT genotypes, hitherto classified as lactase-persistent, differ in their physiological response to lactose intake, indicating differences in phenotype which could have clinical significance. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.
Enko, Dietmar; Pollheimer, Verena; Németh, Stefan; Pühringer, Helene; Stolba, Robert; Halwachs-Baumann, Gabriele; Kriegshäuser, Gernot
2016-01-01
Genetic testing is a standard technique for the diagnosis of primary adult-type hypolactasia, also referred to as lactase non-persistence. The aim of this study was to compare the lactase gene (LCT) C/T-13910 polymorphism genotyping results of two commercially available real-time (RT)-PCR assays in patients referred to our outpatient clinic for primary lactose malabsorption testing. Furthermore, concomitant conditions of fructose/sorbitol malabsorption were assessed. Samples obtained from 100 patients were tested in parallel using the LCT T-13910C ToolSet for Light Cycler (Roche, Rotkreuz, Switzerland) and the LCT-13910C>T RealFast Assay (ViennaLab Diagnostics GmbH, Vienna, Austria). Additionally, patients were also screened for the presence of fructose/sorbitol malabsorption by functional hydrogen (H2)/methane (CH4) breath testing (HMBT). Cohen's Kappa (κ) was used to calculate the agreement between the two genotyping methods. The exact Chi-Square test was performed to compare fructose/sorbitol HMBT with LCT genotyping results. Twenty-one (21.0%) patients had a LCT C/C-13910 genotype suggestive of lactase non-persistence, and 79 (79.0%) patients were identified with either a LCT T/C-13910 or T/T-13910 genotype (i.e., lactase persistence). In all genotype groups, concordance between the two RT-PCR assays was 100%. Cohen's κ demonstrated perfect observed agreement (p < 0.001, κ = 1). Fructose and sorbitol malabsorption was observed in 13/100 (13.0%) and 25/100 (25.0%) individuals, respectively. Both RT-PCR assays are robust and reliable LCT genotyping tools in a routine clinical setting. Concomitant fructose and/or sorbitol malabsorption should be considered in individuals with suspected lactase-non-persistence. However, standardization of clinical interpretation of laboratory HMBT results is required.
Hubácek, Jaroslav A.; Adámková, Věra; Šedová, Lenka; Olišarová, Věra; Adámek, Václav; Tóthová, Valérie
2017-01-01
Abstract Lactase non-persistence (leading to primary lactose intolerance) is a genetically dependent inability to digest lactose in adulthood. As part of the human adaptation to dairying, the human lactase LCT-13910C/T mutation (which propagates adult expression of lactase) developed, spread and participated in the adaptation to dairying. This variant is associated with lactase activity persistence, and its carriers are able to digest lactose. We compared the frequencies of lactase 13910C/T (rs4988235) genotypes in Czechs/Slavs (N = 288) and Czech Gypsies/Roma (N = 300), two ethnically different groups where this polymorphism has not yet been analysed. Allelic frequencies significantly differed between the populations (p < 0.0001). In Czechs/Slavs, the lactase persistence T allele was present in 76% of the individuals, which is in agreement with frequencies among geographically neighbouring populations. In the Czech Gypsy/Roma population, only 27% of the adults were carriers of at least one lactase persistence allele, similar to the Indian population. In agreement with this result, dairy product consumption was reported by 70.5% of Czechs/Slavs and 39.0% of the Czech Gypsy/Roma population. Both in the Czech Gypsy/Roma and in the Czech/Slavs populations, the presence of carriers of the lactase persistence allele was similar in subjects self-reporting the consumption of unfermented/fresh milk, in comparison to the others. PMID:28497837
Hubácek, Jaroslav A; Adámková, Věra; Šedová, Lenka; Olišarová, Věra; Adámek, Václav; Tóthová, Valérie
2017-01-01
Lactase non-persistence (leading to primary lactose intolerance) is a genetically dependent inability to digest lactose in adulthood. As part of the human adaptation to dairying, the human lactase LCT-13910C/T mutation (which propagates adult expression of lactase) developed, spread and participated in the adaptation to dairying. This variant is associated with lactase activity persistence, and its carriers are able to digest lactose. We compared the frequencies of lactase 13910C/T (rs4988235) genotypes in Czechs/Slavs (N = 288) and Czech Gypsies/Roma (N = 300), two ethnically different groups where this polymorphism has not yet been analysed. Allelic frequencies significantly differed between the populations (p < 0.0001). In Czechs/Slavs, the lactase persistence T allele was present in 76% of the individuals, which is in agreement with frequencies among geographically neighbouring populations. In the Czech Gypsy/Roma population, only 27% of the adults were carriers of at least one lactase persistence allele, similar to the Indian population. In agreement with this result, dairy product consumption was reported by 70.5% of Czechs/Slavs and 39.0% of the Czech Gypsy/Roma population. Both in the Czech Gypsy/Roma and in the Czech/Slavs populations, the presence of carriers of the lactase persistence allele was similar in subjects self-reporting the consumption of unfermented/fresh milk, in comparison to the others.
Mattar, Rejane; Monteiro, Maria S; Villares, Cibele A; Santos, Aníbal F; Silva, Joyce M K; Carrilho, Flair J
2009-10-02
Adult-type hypolactasia, the physiological decline of lactase some time after weaning, was previously associated with the LCT -13910C>T polymorphism worldwide except in Africa. Lactase non-persistence is the most common phenotype in humans, except in northwestern Europe with its long history of pastoralism and milking. We had previously shown association of LCT -13910C>T polymorphism with adult-type hypolactasia in Brazilians; thus, we assessed its frequency among different Brazilian ethnic groups. We investigated the ethnicity-related frequency of this polymorphism in 567 Brazilians [mean age, 42.1 +/- 16.8 years; 157 (27.7%) men]; 399 (70.4%) White, 50 (8.8%) Black, 65 (11.5%) Brown, and 53 (9.3%) Japanese-Brazilian. DNA was extracted from leukocytes; LCT -13910C>T polymorphism was analyzed by PCR-restriction fragment length polymorphism. Prevalence of the CC genotype associated with hypolactasia was similar (57%) among White and Brown groups; however, prevalence was higher among Blacks (80%) and those of Japanese descent (100%). Only 2 (4%) Blacks had TT genotype, and 8 (16%) had the CT genotype. Assuming an association between CC genotype and hypolactasia, and CT and TT genotypes with lactase persistence, 356 (62.8%) individuals had hypolactasia and 211 (37.2%) had lactase persistence. The White and Brown groups had the same hypolactasia prevalence (approximately 57%); nevertheless, was 80% among Black individuals and 100% among Japanese-Brazilians (P < 0.01). The lactase persistence allele, LCT -13910T, was found in about 43% of both White and Brown and 20% of the Black Brazilians, but was absent among all Japanese Brazilians studied.
Abildgaard, Anders; Tovbjerg, Sara K; Giltay, Axel; Detemmerman, Liselot; Nissen, Peter H
2018-03-26
The lactase persistence phenotype is controlled by a regulatory enhancer region upstream of the Lactase (LCT) gene. In northern Europe, specifically the -13910C > T variant has been associated with lactase persistence whereas other persistence variants, e.g. -13907C > G and -13915 T > G, have been identified in Africa and the Middle East. The aim of the present study was to compare a previously developed high resolution melting assay (HRM) with a novel method based on loop-mediated isothermal amplification and melting curve analysis (LAMP-MC) with both whole blood and DNA as input material. To evaluate the LAMP-MC method, we used 100 whole blood samples and 93 DNA samples in a two tiered study. First, we studied the ability of the LAMP-MC method to produce specific melting curves for several variants of the LCT enhancer region. Next, we performed a blinded comparison between the LAMP-MC method and our existing HRM method with clinical samples of unknown genotype. The LAMP-MC method produced specific melting curves for the variants at position -13909, -13910, -13913 whereas the -13907C > G and -13915 T > G variants produced indistinguishable melting profiles. The LAMP-MC assay is a simple method for lactase persistence genotyping and compares well with our existing HRM method. Copyright © 2018. Published by Elsevier B.V.
Ojeda-Granados, Claudia; Panduro, Arturo; Rebello Pinho, João Renato; Ramos-Lopez, Omar; Gleyzer, Ketti; Malta, Fernanda de Mello; Gonzalez-Aldaco, Karina; Roman, Sonia
2016-01-01
Lactase (LCT) -13910 C>T and -22018 G>A polymorphisms associated with the lactase non-persistence (LNP)/persistence (LP) phenotypes vary globally. LP has been associated with obesity in Europeans. However, it has not been genetically evaluated in Mexico, a country with admixed population, recent introduction of dairy, and a high prevalence of obesity. Thus, we aimed to determine the distribution of the LCT polymorphisms and their association with the nutritional profile of West Mexico's populations. Genotyping of 1,196 individuals (natives and mestizos) was carried out by a Taqman allelic discrimination assay. Descriptive statistics and interpopulation analyzes were performed by SPSS, Arlequin, and Structure software. Demographic, anthropometric, biochemical and dietary data were analyzed in 212 mestizos. LNP genotypes mainly prevailed (CC 68.7% and GG 68.2%); both predominated in native Huicholes and Nahuas (>97.7%). Among the mestizos, the LP genotypes were associated with a higher intake of saturated fat (9.9 ± 3.9% vs. 8.5 ± 4.0%, p = 0.018; OR = 2.55, 95% CI 1.29-5.03, p = 0.006) and a daily/more frequent consumption of dairy (88.8 vs. 78.0%; p = 0.049) than LNP genotypes. The LNP trait was predominant in Mexicans with a major Amerindian ancestry. A daily consumption of dairy was associated with a higher intake of saturated fat in LP individuals. © 2016 S. Karger AG, Basel.
Boschmann, Stefanie Epp; Boldt, Angelica Beate; de Souza, Ilíada Rainha; Petzl-Erler, Maria Luiza; Messias-Reason, Iara Jose
2016-01-01
The aim of this study was to investigate the frequency of the LCT*-13910C>T polymorphism associated with a high expression of lactase in the small intestine during adulthood, and to infer the lactase persistence and adult-type hypolactasia phenotypes among Euro-Brazilians and Mennonites from South Brazil. A sequence-specific PCR method to genotype the LCT*-13910C>T polymorphism in 292 Euro-Brazilians and 151 Mennonites (a group with European ancestry and a long history of endogamy) was developed. Using an exact test of population differentiation, the genotype and allele frequency between these and other Brazilian populations were compared. The frequency of -13910*T was significantly higher among the Mennonites when compared to the Euro-Brazilian cohort (0.63 vs. 0.33, p < 0.000001). Accordingly, Mennonites had a higher prevalence of the lactase persistence genotype (88.1 vs. 55.5%, p < 0.000001). The distribution of -13910*T differed between Mennonites and all other Brazilian groups (p < 0.0001). The Euro-Brazilians from Curitiba displayed differences when compared to all other Brazilian groups (p < 0.0001), even to Euro-Brazilians from a different geographic region (p = 0.0003), but were similar to those from Porto Alegre (p = 0.2). Differences in the -13910*T-associated lactase persistence distribution among Euro-Brazilian groups reflect the ancestry and admixture of each particular group and should be considered for adult-type hypolactasia screening. © 2015 S. Karger AG, Basel.
Morales, Eugenia; Azocar, Lorena; Maul, Ximena; Perez, Claudio; Chianale, José
2011-01-01
Background The lactase persistent (LP) or lactase non-persistent (LNP) state in European adults is genetically determined by a single nucleotide polymorphism (SNP) located 13.9 kb upstream of the lactase (LCT) gene, known as LCT C>T−13910 (rs4988235). The LNP condition leads to an inability to digest the milk sugar lactose leading to gastrointestinal symptoms and can affect nutrient and calcium intake in certain populations. Objectives The authors studied a group of 51 Chilean patients to assess whether this SNP influences the LP/LNP state in this population, and determined the prevalence of LCT C>T−13910 genotypes in a representative sample of 216 Hispanics and 43 Amerindians with correlation to digestive symptoms. Design Case–control study done in Chilean patients with clinical suspicion of LNP that were assessed using clinical survey, hydrogen breath test (HBT) and SNP genotyping. The population sample of Hispanics and Amerindians was assessed by clinical survey and SNP genotyping. Results Of the 51 patients with clinical suspicion of LNP, 29 were HBT-positive. The CC genotype (LNP) was present in 89.7% of the patients with positive HBT and in only 4.7% of those with negative HBT. The prevalence of the CC genotype was 56.9% in the Hispanic population and 88.3% in Amerindians, and was associated with a higher self-reported clinical intolerance to ingestion of dairy products. Conclusion The LP/LNP state is determined by the LCT C>T−13910 variant in Chileans. This variant predicts digestive symptoms associated with the ingestion of lactose and is a good tool for the diagnosis of primary adult hypolactasia. The LCT T−13910 allele is rare in the Amerindian population and is suggestive of European ancestry in this contemporary population. PMID:22021768
ERIC Educational Resources Information Center
Weinlander, Kenneth M.; Hall, David J.; De Stasio, Elizabeth A.
2010-01-01
We describe here two open-ended laboratory investigations for an undergraduate laboratory course that uses students' DNA as templates for quantitative real-time PCR and for traditional PCR followed by RFLP analysis. Students are captivated by the immediacy of the application and the relevance of the genotypes and traits, lactase persistence or…
Hypolactasia is associated with insulin resistance in nonalcoholic steatohepatitis
de Campos Mazo, Daniel Ferraz; Mattar, Rejane; Stefano, José Tadeu; da Silva-Etto, Joyce Matie Kinoshita; Diniz, Márcio Augusto; Duarte, Sebastião Mauro Bezerra; Rabelo, Fabíola; Lima, Rodrigo Vieira Costa; de Campos, Priscila Brizolla; Carrilho, Flair José; Oliveira, Claudia P
2016-01-01
AIM To assess lactase gene (LCT)-13910C>T polymorphisms in Brazilian non-alcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) patients in comparison with healthy controls. METHODS This was a transverse observational clinical study with NAFLD patients who were followed at the Hepatology Outpatient Unit of the Hospital das Clínicas, São Paulo, Brazil. The polymorphism of lactase non-persistence/lactase persistence (LCT-13910C>T) was examined by PCR-restriction fragment length polymorphism technique in 102 liver biopsy-proven NAFLD patients (steatosis in 9 and NASH in 93) and compared to those of 501 unrelated healthy volunteers. Anthropometric, clinical, biochemical and liver histology data were analyzed. Continuous variables were compared using the t or Mann-Whitney tests, and categorical data were compared with the Fisher’s exact test. Univariate logistic regression and multivariate logistic regression adjusted for gender and age were performed. RESULTS No differences in the LCT-13910 genotype frequencies were noted between the NAFLD patients (66.67% of the patients with steatosis were CC, 33.33% were CT, and none were TT; 55.91% of the patients with NASH were CC, 39.78% were CT, and 4.3% were TT; P = 0.941) and the healthy controls (59.12% were CC, 35.67% were CT, and 5.21% were TT) or between the steatosis and NASH patients. That is, the distribution of the lactase non-persistence/lactase persistence polymorphism (LCT-13910C>T) in the patients with NAFLD was equal to that in the general population. In the NASH patients, the univariate analysis revealed that the lactase non-persistence (low lactase activity or hypolactasia) phenotype was associated with higher insulin levels (23.47 ± 15.94 μU/mL vs 15.8 ± 8.33 μU/mL, P = 0.027) and a higher frequency of insulin resistance (91.84% vs 72.22%, P = 0.02) compared with the lactase persistence phenotype. There were no associations between the LCT genotypes and diabetes (P = 0.651), dyslipidaemia (P = 0.328), hypertension (P = 0.507) or liver histology in these patients. Moreover, in the NASH patients, hypolactasia was an independent risk factor for insulin resistance even after adjusting for gender and age [OR = 5.0 (95%CI: 1.35-20; P = 0.017)]. CONCLUSION The LCT-13910 genotype distribution in Brazilian NAFLD patients was the same as that of the general population, but hypolactasia increased the risk of insulin resistance in the NASH patients. PMID:27648154
Friedrich, Deise C.; Santos, Sidney E. B.; Ribeiro-dos-Santos, Ândrea K. C.; Hutz, Mara H.
2012-01-01
Adult-type hypolactasia is a common phenotype caused by the lactase enzyme deficiency. The −13910 C>T polymorphism, located 14 Kb upstream of the lactase gene (LCT) in the MCM6 gene was associated with lactase persistence (LP) in Europeans. This polymorphism is rare in Africa but several other variants associated with lactase persistence were observed in Africans. The aims of this study were to identify polymorphisms in the MCM6 region associated with the lactase persistence phenotype and to determine the distribution of LCT gene haplotypes in 981 individuals from North, Northeast and South Brazil. These polymorphisms were genotyped by PCR based methods and sequencing. The −13779*C,−13910*T, −13937*A, −14010*C, −14011*T LP alleles previously described in the MCM6 gene region that acts as an enhancer for the LCT gene were identified in Brazilians. The most common LP allele was −13910*T. Its frequency was highly correlated with European ancestry in the Brazilian populations investigated. The −13910*T was higher (0.295) in southern Brazilians of European ancestry and lower (0.175) in the Northern admixed population. LCT haplotypes were derived from the 10 LCT SNPs genotyped. Overall twenty six haplotypes previously described were identified in the four Brazilian populations studied. The Multidimensional Scaling analysis showed that Belém, in the north, was closer to Amerindians. Northeastern and southern Afro-descendants were more related with Bantu-speaking South Africans whereas the Southern population with European ancestry grouped with Southern and Northern Europeans. This study shows a high variability considering the number of LCT haplotypes observed. Due to the highly admixed nature of the Brazilian populations, the diagnosis of hypolactasia in Brazil, based only in the investigation of the −13910*T allele is an oversimplification. PMID:23029545
Body fat and dairy product intake in lactase persistent and non-persistent children and adolescents.
Almon, Ricardo; Patterson, Emma; Nilsson, Torbjörn K; Engfeldt, Peter; Sjöström, Michael
2010-06-16
Lactase non-persistent (LNP) individuals may be lactose intolerant and therefore on a more restricted diet concerning milk and milk products compared to lactase persistent (LP) individuals. This may have an impact on body fat mass. This study examines if LP and LNP children and adolescents, defined by genotyping for the LCT-13910 C > T polymorphism, differ from each other with regard to milk and milk product intake, and measures of body fat mass. Children (n=298, mean age 9.6 years) and adolescents (n=386, mean age 15.6 years), belonging to the Swedish part of the European Youth Heart Study, were genotyped for the LCT-13910 C > T polymorphism. Dietary intakes of reduced and full-fat dairy varieties were determined. LNP (CC genotype) subjects consumed less milk, soured milk and yoghurt compared to LP (CT/TT genotype) subjects (p<0.001). Subsequent partitioning for age group attenuated this observation (p=0.002 for children and p=0.023 in adolescents). Six subjects were reported by parents to be 'lactose intolerant', none of whom were LNP. LNP children and adolescents consumed significantly less reduced fat milk and milk products than LP children and adolescents (p=0.009 for children and p=0.001 for adolescents). We conclude that LP is linked to an overall higher milk and dairy intake, but is not linked to higher body fat mass in children and adolescents.
Mattar, Rejane; Basile-Filho, Anibal; Kemp, Rafael; Santos, José Sebastião dos
2013-01-01
To analyze the usefulness of Quick Lactose Intolerance Test in relation to the genetic test based on LCT-13910C>T genotypes, previously validated for clinical practice, for primary hypolactasia/lactase-persistence diagnosis. Thirty-two dyspeptic patients that underwent upper gastrointestinal endoscopy entered the study. Two postbulbar duodenal biopsies were taken for the Quick test, and gastric antral biopsy for DNA extraction and LCT-13910C>T polymorphism analysis. DNA was also extracted from biopsies after being used in the Quick Test that was kept frozen until extraction. Nine patients with lactase-persistence genotype (LCT-13910CT or LCT-13910TT) had normolactasia, eleven patients with hypolactasia genotype (LCT-13910CC) had severe hypolactasia, and among twelve with mild hypolactasia, except for one that had LCT-13910CT genotype, all the others had hypolactasia genotype. The agreement between genetic test and quick test was high (p<0.0001; Kappa Index 0.92). Most of the patients that reported symptoms with lactose-containing food ingestion had severe hypolactasia (p<0.05). Amplification with good quality PCR product was also obtained with DNA extracted from biopsies previously used in the Quick Test; thus, for the future studies antral gastric biopsies for genetic test would be unnecessary. Quick test is highly sensitive and specific for hypolactasia diagnosis and indicated those patients with symptoms of lactose intolerance.
Bergholdt, Helle K M; Nordestgaard, Børge G; Ellervik, Christina
2015-08-01
High dairy/milk intake has been associated with a low risk of type 2 diabetes observationally, but whether this represents a causal association is unknown. We tested the hypothesis that high milk intake is associated with a low risk of type 2 diabetes and of overweight-obesity, observationally and genetically. In 97,811 individuals from the Danish general population, we examined the risk of incident type 2 diabetes and of overweight-obesity by milk intake observationally and by LCT-13910 C/T genotype [polymorphism (rs4988235) upstream from the lactase (LCT) gene], where TT and TC genotypes are associated with lactase persistence and CC with nonpersistence. Observationally for any compared with no milk intake, the HR for type 2 diabetes was 1.10 (95% CI: 0.98, 1.24; P = 0.11), whereas the OR for overweight-obesity was 1.06 (1.02, 1.09; P = 0.002). Median milk intake was 5 glasses/wk (IQR: 0-10) for lactase TT/TC persistence and 3 (0-7) for CC nonpersistence. Genetically for lactase TT/TC persistence compared with CC nonpersistence, the OR was 0.96 (0.86, 1.08; P = 0.50) for type 2 diabetes and 1.06 (1.00, 1.12; P = 0.04) for overweight-obesity. In a stratified analysis for type 2 diabetes, corresponding values in those with and without milk intake were 0.88 (0.76, 1.03; P = 0.11) and 1.35 (1.07, 1.70; P = 0.01) (P-interaction: 0.002), whereas no gene-milk interaction on overweight-obesity was found. For a 1-glass/wk higher milk intake, the genetic risk ratio for type 2 diabetes was 0.99 (0.93, 1.06), and the corresponding observational risk was 1.01 (1.00, 1.01). For overweight-obesity, the corresponding values were 1.01 (1.00, 1.02) genetically and 1.00 (1.00, 1.01) observationally. High milk intake is not associated with a low risk of type 2 diabetes or overweight-obesity, observationally or genetically via lactase persistence. The higher risk of type 2 diabetes in lactase-persistent individuals without milk intake likely is explained by collider stratification bias. © 2015 American Society for Nutrition.
Baadkar, Shruti V; Mukherjee, Manjari S; Lele, Smita S
2014-01-01
Lactase non-persistence (LNP) has been associated with the CC genotype of -13910C > T and GG genotype of -22018G > A polymorphisms present upstream of the lactase gene. Lactose intolerance (LI) is caused when gastrointestinal symptoms develop in individuals with low lactase activity. To analyse association of LNP genotype and LI symptoms with milk intake and determine whether factors such as age, gender and genotype affect LI status. Genetic analysis and lactose tolerance test (LTT) were performed on 205 healthy Indian adults. The pattern of milk consumption was recorded using a dietary questionnaire. LI was strongly associated with -13910CC genotype (OR = 10.28, 95% CI = 2.32-45.55, p = 0.002). Females were found to be at a higher risk of developing LI (OR = 2.47, 95% CI = 1.33-4.59, p = 0.004). The association of the ≥50 years age group with LI was marginally significant (OR = 1.86, 95% CI = 0.995-3.47, p = 0.05). Frequency and quantity of milk intake were lower in subjects belonging to the LNP genotype and LI groups (p < 0.05). Subject study suggests that gender and genotype may be associated with development of LI. Association of age with LI was marginal. The data also indicate that LNP genotype and LI may play a role in influencing milk intake in individuals.
Lactase persistence and dairy intake in Mapuche and Mestizo populations from southern Chile.
Fernández, Catalina I; Flores, Sergio V
2014-11-01
Lactase persistence (LP) occurs at a very low frequency in indigenous populations from Latin America, offering an opportunity to understand the relationship between this genetic trait and patterns of dairy consumption. Here, the frequency of LP is analyzed from Mapuche and -an adjacent- mestizo population inhabiting the Araucanía region. In addition to genotyping for LP, participants were surveyed in relation to general perception and consumption habits of dairy products. Low LP frequency (10%) and very low dairy intake was found among the Mapuche population as compared with Mestizo populations inhabiting Chile. The survey reported that the main reasons for avoidance of dairy were the gastrointestinal symptoms after dairy intake and cultural dietary habits. The interaction between low LP genotype frequency, low dairy intake, and sociocultural determinants is here discussed in the light of their potential health outcomes. © 2014 Wiley Periodicals, Inc.
Low prevalence of lactase persistence in Neolithic South-West Europe
Plantinga, Theo S; Alonso, Santos; Izagirre, Neskuts; Hervella, Montserrat; Fregel, Rosa; van der Meer, Jos WM; Netea, Mihai G; de la Rúa, Concepcion
2012-01-01
The ability of humans to digest the milk component lactose after weaning requires persistent production of the lactose-converting enzyme lactase. Genetic variation in the promoter of the lactase gene (LCT) is known to be associated with lactase production and is therefore a genetic determinant for either lactase deficiency or lactase persistence during adulthood. Large differences in this genetic trait exist between populations in Africa and the Middle-East on the one hand, and European populations on the other; this is thought to be due to evolutionary pressures exerted by consumption of dairy products in Neolithic populations in Europe. In this study, we have investigated lactase persistence of 26 out of 46 individuals from Late Neolithic through analysis of ancient South-West European DNA samples, obtained from two burials in the Basque Country originating from 5000 to 4500 YBP. This investigation revealed that these populations had an average frequency of lactase persistence of 27%, much lower than in the modern Basque population, which is compatible with the concept that Neolithic and post-Neolithic evolutionary pressures by cattle domestication and consumption of dairy products led to high lactase persistence in Southern European populations. Given the heterogeneity in the frequency of the lactase persistence allele in ancient Europe, we suggest that in Southern Europe the selective advantage of lactose assimilation in adulthood most likely took place from standing population variation, after cattle domestication, at a post-Neolithic time when fresh milk consumption was already fully adopted as a consequence of a cultural influence. PMID:22234158
Lactase non-persistence is directed by DNA variation-dependent epigenetic aging
Labrie, Viviane; Buske, Orion J; Oh, Edward; Jeremian, Richie; Ptak, Carolyn; Gasiūnas, Giedrius; Maleckas, Almantas; Petereit, Rūta; Žvirbliene, Aida; Adamonis, Kęstutis; Kriukienė, Edita; Koncevičius, Karolis; Gordevičius, Juozas; Nair, Akhil; Zhang, Aiping; Ebrahimi, Sasha; Oh, Gabriel; Šikšnys, Virginijus; Kupčinskas, Limas; Brudno, Michael; Petronis, Arturas
2016-01-01
Inability to digest lactose due to lactase non-persistence is a common trait in adult mammals, with the exception of certain human populations that exhibit lactase persistence. It is not clear how the lactase gene can be dramatically downregulated with age in most individuals, but remains active in some. We performed a comprehensive epigenetic study of the human and mouse intestine using chromosome-wide DNA modification profiling and targeted bisulfite sequencing. Epigenetically-controlled regulatory elements were found to account for the differences in lactase mRNA levels between individuals, intestinal cell types and species. The importance of these regulatory elements in modulating lactase mRNA levels was confirmed by CRISPR-Cas9-induced deletions. Genetic factors contribute to epigenetic changes occurring with age at the regulatory elements, as lactase persistence- and non-persistence-DNA haplotypes demonstrated markedly different epigenetic aging. Thus, genetic factors facilitate a gradual accumulation of epigenetic changes with age to affect phenotypic outcome. PMID:27159559
Evolution of lactase persistence: an example of human niche construction
Gerbault, Pascale; Liebert, Anke; Itan, Yuval; Powell, Adam; Currat, Mathias; Burger, Joachim; Swallow, Dallas M.; Thomas, Mark G.
2011-01-01
Niche construction is the process by which organisms construct important components of their local environment in ways that introduce novel selection pressures. Lactase persistence is one of the clearest examples of niche construction in humans. Lactase is the enzyme responsible for the digestion of the milk sugar lactose and its production decreases after the weaning phase in most mammals, including most humans. Some humans, however, continue to produce lactase throughout adulthood, a trait known as lactase persistence. In European populations, a single mutation (−13910*T) explains the distribution of the phenotype, whereas several mutations are associated with it in Africa and the Middle East. Current estimates for the age of lactase persistence-associated alleles bracket those for the origins of animal domestication and the culturally transmitted practice of dairying. We report new data on the distribution of −13910*T and summarize genetic studies on the diversity of lactase persistence worldwide. We review relevant archaeological data and describe three simulation studies that have shed light on the evolution of this trait in Europe. These studies illustrate how genetic and archaeological information can be integrated to bring new insights to the origins and spread of lactase persistence. Finally, we discuss possible improvements to these models. PMID:21320900
Fernández, Catalina I; Montalva, Nicolás; Arias, Macarena; Hevia, Macarena; Moraga, Mauricio L; Flores, Sergio V
2016-01-01
Lactase persistence (LP) is a genetic trait that has been studied among different countries and ethnic groups. In Latin America, the frequencies of this trait have been shown to vary according to the degree of admixture of the populations. The objective of this study is to better understand the relationship between this genetic trait and dairy intake in a multiethnic context through a synthesis of studies conducted in four regions of Chile. Genotypes frequencies for the SNP LCT-13910C>T (rs4988235) and frequency of dairy consumption were obtained from four populations: Polynesians from Easter Island (Rapanui); Amerindians (Mapuche) and Mestizos from the Araucanía region; urban Mestizos from Santiago; and rural Mestizos from the Coquimbo region. Genetic differentiation and association between milk consumption and genotype frequencies were estimated. Genetic differentiation between Native and Mestizo populations was significant; the LP frequency in Mapuche and Rapanui was 10% and 25%, respectively, whereas among the Mestizos, LP frequency was near 40%. Dairy intake was below the nutritional recommendations for the four groups, and extremely below recommendations among the indigenous populations. Association between milk intake and LP was found in Santiago and Rapanui populations. Although the frequency of LP varies among the populations according to their degree of admixture, dairy consumption was very low across the populations. Given that the association between milk consumption and expected phenotype was found only in two of the populations analyzed, it seems that lactase non-persistence (LNP) is not the only cause for dairy avoidance. Thus, it is suggested that SES and cultural preferences are likely affecting dairy consumption. © 2015 Wiley Periodicals, Inc.
Impact of selection and demography on the diffusion of lactase persistence.
Gerbault, Pascale; Moret, Céline; Currat, Mathias; Sanchez-Mazas, Alicia
2009-07-24
The lactase enzyme allows lactose digestion in fresh milk. Its activity strongly decreases after the weaning phase in most humans, but persists at a high frequency in Europe and some nomadic populations. Two hypotheses are usually proposed to explain the particular distribution of the lactase persistence phenotype. The gene-culture coevolution hypothesis supposes a nutritional advantage of lactose digestion in pastoral populations. The calcium assimilation hypothesis suggests that carriers of the lactase persistence allele(s) (LCT*P) are favoured in high-latitude regions, where sunshine is insufficient to allow accurate vitamin-D synthesis. In this work, we test the validity of these two hypotheses on a large worldwide dataset of lactase persistence frequencies by using several complementary approaches. We first analyse the distribution of lactase persistence in various continents in relation to geographic variation, pastoralism levels, and the genetic patterns observed for other independent polymorphisms. Then we use computer simulations and a large database of archaeological dates for the introduction of domestication to explore the evolution of these frequencies in Europe according to different demographic scenarios and selection intensities. Our results show that gene-culture coevolution is a likely hypothesis in Africa as high LCT*P frequencies are preferentially found in pastoral populations. In Europe, we show that population history played an important role in the diffusion of lactase persistence over the continent. Moreover, selection pressure on lactase persistence has been very high in the North-western part of the continent, by contrast to the South-eastern part where genetic drift alone can explain the observed frequencies. This selection pressure increasing with latitude is highly compatible with the calcium assimilation hypothesis while the gene-culture coevolution hypothesis cannot be ruled out if a positively selected lactase gene was carried at the front of the expansion wave during the Neolithic transition in Europe.
The origins of lactase persistence in Europe.
Itan, Yuval; Powell, Adam; Beaumont, Mark A; Burger, Joachim; Thomas, Mark G
2009-08-01
Lactase persistence (LP) is common among people of European ancestry, but with the exception of some African, Middle Eastern and southern Asian groups, is rare or absent elsewhere in the world. Lactase gene haplotype conservation around a polymorphism strongly associated with LP in Europeans (-13,910 C/T) indicates that the derived allele is recent in origin and has been subject to strong positive selection. Furthermore, ancient DNA work has shown that the--13,910*T (derived) allele was very rare or absent in early Neolithic central Europeans. It is unlikely that LP would provide a selective advantage without a supply of fresh milk, and this has lead to a gene-culture coevolutionary model where lactase persistence is only favoured in cultures practicing dairying, and dairying is more favoured in lactase persistent populations. We have developed a flexible demic computer simulation model to explore the spread of lactase persistence, dairying, other subsistence practices and unlinked genetic markers in Europe and western Asia's geographic space. Using data on--13,910*T allele frequency and farming arrival dates across Europe, and approximate Bayesian computation to estimate parameters of interest, we infer that the--13,910*T allele first underwent selection among dairying farmers around 7,500 years ago in a region between the central Balkans and central Europe, possibly in association with the dissemination of the Neolithic Linearbandkeramik culture over Central Europe. Furthermore, our results suggest that natural selection favouring a lactase persistence allele was not higher in northern latitudes through an increased requirement for dietary vitamin D. Our results provide a coherent and spatially explicit picture of the coevolution of lactase persistence and dairying in Europe.
The Origins of Lactase Persistence in Europe
Itan, Yuval; Powell, Adam; Beaumont, Mark A.; Burger, Joachim; Thomas, Mark G.
2009-01-01
Lactase persistence (LP) is common among people of European ancestry, but with the exception of some African, Middle Eastern and southern Asian groups, is rare or absent elsewhere in the world. Lactase gene haplotype conservation around a polymorphism strongly associated with LP in Europeans (−13,910 C/T) indicates that the derived allele is recent in origin and has been subject to strong positive selection. Furthermore, ancient DNA work has shown that the −13,910*T (derived) allele was very rare or absent in early Neolithic central Europeans. It is unlikely that LP would provide a selective advantage without a supply of fresh milk, and this has lead to a gene-culture coevolutionary model where lactase persistence is only favoured in cultures practicing dairying, and dairying is more favoured in lactase persistent populations. We have developed a flexible demic computer simulation model to explore the spread of lactase persistence, dairying, other subsistence practices and unlinked genetic markers in Europe and western Asia's geographic space. Using data on −13,910*T allele frequency and farming arrival dates across Europe, and approximate Bayesian computation to estimate parameters of interest, we infer that the −13,910*T allele first underwent selection among dairying farmers around 7,500 years ago in a region between the central Balkans and central Europe, possibly in association with the dissemination of the Neolithic Linearbandkeramik culture over Central Europe. Furthermore, our results suggest that natural selection favouring a lactase persistence allele was not higher in northern latitudes through an increased requirement for dietary vitamin D. Our results provide a coherent and spatially explicit picture of the coevolution of lactase persistence and dairying in Europe. PMID:19714206
Lactose intolerance: a non-allergic disorder often managed by allergologists.
Perino, A; Cabras, S; Obinu, D; Cavalli Sforza, L
2009-02-01
Lactose malabsorption is a very common condition characterized by intestinal lactase deficiency. Primary lactose malabsorption is an inherited deficit present in the majority of the world's population, while secondary bypolactasia can be the consequence of an intestinal disease. The presence of malabsorbed lactose in the colonic lumen may cause gastrointestinal symptoms. This condition is known as lactose intolerance. Lactase non-persistence is the ancestral state, whilst two single nucleotide polymorphisms in the lactase gene have been associated with lactase persistence. These are C/T 13910 and G/A 22018 substitutions. Lactase persistence, this Mendelian dominant trait, only became advantageous after the invention of agriculture, when milk from domesticated animals became available for adults to drink. Lactase persistence is then strongly correlated with the diary history of the population. Diagnosis is assessed clinically by elimination of dietary lactose or, better, by non-invasive tests including hydrogen breath test and genetic test. In patients with lactase non-persistence, treatment should be considered exclusively if intolerance symptoms are present. In the absence of guidelines, the common therapeutic approach tends to exclude milk and dairy products from the diet. However, this strategy may have serious nutritional disadvantages. Several studies have been carried out to find alternative approaches, such as exogenous beta-galactosidase, yogurt and probiotics for their bacterial lactase activity, strategies that can prolong contact time between enzyme and substrate delaying gastrointestinal transit time, and chronic lactose ingestion to enhance colonic adaptation.
Obermayer-Pietsch, Barbara M; Bonelli, Christine M; Walter, Daniela E; Kuhn, Regina J; Fahrleitner-Pammer, Astrid; Berghold, Andrea; Goessler, Walter; Stepan, Vinzenz; Dobnig, Harald; Leb, Georg; Renner, Wilfried
2004-01-01
Evidence that genetic disposition for adult lactose intolerance significantly affects calcium intake, bone density, and fractures in postmenopausal women is presented. PCR-based genotyping of lactase gene polymorphisms may complement diagnostic procedures to identify persons at risk for both lactose malabsorption and osteoporosis. Lactase deficiency is a common autosomal recessive condition resulting in decreased intestinal lactose degradation. A -13910 T/C dimorphism (LCT) near the lactase phlorizin hydrolase gene, reported to be strongly associated with adult lactase nonpersistence, may have an impact on calcium supply, bone density, and osteoporotic fractures in the elderly. We determined LCT genotypes TT, TC, and CC in 258 postmenopausal women using a polymerase chain reaction-based assay. Genotypes were related to milk intolerance, nutritional calcium intake, intestinal calcium absorption, bone mineral density (BMD), and nonvertebral fractures. Twenty-four percent of all women were found to have CC genotypes and genetic lactase deficiency. Age-adjusted BMD at the hip in CC genotypes and at the spine in CC and TC genotypes was reduced by -7% to -11% depending on the site measured (p = 0.04). LCT(T/C-13910) polymorphisms alone accounted for 2-4% of BMD in a multiple regression model. Bone fracture incidence was significantly associated with CC genotypes (p = 0.001). Milk calcium intake was significantly lower (-55%, p = 0.004) and aversion to milk consumption was significantly higher (+166%, p = 0.01) in women with the CC genotype, but there were no differences in overall dietary calcium intake or in intestinal calcium absorption test values. The LCT(T/C-13910) polymorphism is associated with subjective milk intolerance, reduced milk calcium intake, and reduced BMD at the hip and the lumbar spine and may predispose to bone fractures. Genetic testing for lactase deficiency may complement indirect methods in the detection of individuals at risk for both lactose malabsorption and osteoporosis.
Lactase Non-persistence and Lactose Intolerance.
Bayless, Theodore M; Brown, Elizabeth; Paige, David M
2017-05-01
To evaluate the clinical and nutritional significance of genetically determined lactase non-persistence and potential lactose and milk intolerance in 65-70% of the world's adult population. Milk consumption is decreasing in the USA and is the lowest in countries with a high prevalence of lactase non-persistence. The dairy industry and Minnesota investigators have made efforts to minimize the influence of lactose intolerance on milk consumption. Some lactose intolerant individuals, without co-existent irritable bowel syndrome, are able to consume a glass of milk with a meal with no or minor symptoms. The high frequency of lactase persistence in offspring of Northern European countries and in some nomadic African tribes is due to mutations in the promoter of the lactase gene in association with survival advantage of milk drinking. Educational and commercial efforts to improve calcium and Vitamin D intake have focused on urging consumption of tolerable amounts of milk with a meal, use of lowered lactose-content foods including hard cheeses, yogurt, and lactose-hydrolyzed milk products.
Adult lactose digestion status and effects on disease
Szilagyi, Andrew
2015-01-01
BACKGROUND: Adult assimilation of lactose divides humans into dominant lactase-persistent and recessive nonpersistent phenotypes. OBJECTIVES: To review three medical parameters of lactose digestion, namely: the changing concept of lactose intolerance; the possible impact on diseases of microbial adaptation in lactase-nonpersistent populations; and the possibility that the evolution of lactase has influenced some disease pattern distributions. METHODS: A PubMed, Google Scholar and manual review of articles were used to provide a narrative review of the topic. RESULTS: The concept of lactose intolerance is changing and merging with food intolerances. Microbial adaptation to regular lactose consumption in lactase-nonpersistent individuals is supported by limited evidence. There is evidence suggestive of a relationship among geographical distributions of latitude, sunhine exposure and lactase proportional distributions worldwide. DISCUSSION: The definition of lactose intolerance has shifted away from association with lactose maldigestion. Lactose sensitivity is described equally in lactose digesters and maldigesters. The important medical consequence of withholding dairy foods could have a detrimental impact on several diseases; in addition, microbial adaptation in lactase-nonpersistent populations may alter risk for some diseases. There is suggestive evidence that the emergence of lactase persistence, together with human migrations before and after the emergence of lactase persistence, have impacted modern-day diseases. CONCLUSIONS: Lactose maldigestion and lactose intolerance are not synonymous. Withholding dairy foods is a poor method to treat lactose intolerance. Further epidemiological work could shed light on the possible effects of microbial adaptation in lactose maldigesters. The evolutionary impact of lactase may be still ongoing. PMID:25855879
Adult lactose digestion status and effects on disease.
Szilagyi, Andrew
2015-04-01
Adult assimilation of lactose divides humans into dominant lactase-persistent and recessive nonpersistent phenotypes. To review three medical parameters of lactose digestion, namely: the changing concept of lactose intolerance; the possible impact on diseases of microbial adaptation in lactase-nonpersistent populations; and the possibility that the evolution of lactase has influenced some disease pattern distributions. A PubMed, Google Scholar and manual review of articles were used to provide a narrative review of the topic. The concept of lactose intolerance is changing and merging with food intolerances. Microbial adaptation to regular lactose consumption in lactase-nonpersistent individuals is supported by limited evidence. There is evidence suggestive of a relationship among geographical distributions of latitude, sunhine exposure and lactase proportional distributions worldwide. The definition of lactose intolerance has shifted away from association with lactose maldigestion. Lactose sensitivity is described equally in lactose digesters and maldigesters. The important medical consequence of withholding dairy foods could have a detrimental impact on several diseases; in addition, microbial adaptation in lactase-nonpersistent populations may alter risk for some diseases. There is suggestive evidence that the emergence of lactase persistence, together with human migrations before and after the emergence of lactase persistence, have impacted modern-day diseases. Lactose maldigestion and lactose intolerance are not synonymous. Withholding dairy foods is a poor method to treat lactose intolerance. Further epidemiological work could shed light on the possible effects of microbial adaptation in lactose maldigesters. The evolutionary impact of lactase may be still ongoing.
Genetic diversity of lactase persistence in East African populations.
Hassan, Hisham Y; van Erp, Anke; Jaeger, Martin; Tahir, Hanan; Oosting, Marije; Joosten, Leo A B; Netea, Mihai G
2016-01-04
The expression of lactase which digests lactose from milk in humans is generally lost after weaning, but selected mutations influencing the promoter of the lactase gene have spread into the human populations. This is considered a classical example of gene-culture co-evolution, and several studies suggested that the lactase gene has been under strong directional evolutionary selective pressure in the past 5000 to 10,000 years. In the present study we investigated the distribution of three gene variants leading to lactase persistence in 12 different East African populations as well as one European population. Our results show that with the exception of Copts and Nilotic populations who are fully lactose non-persistent, the majority of populations of East Africa show at least partly lactose persistence, with both ethnic and socio-economic aspects playing an important role in the distribution of genetic variants. In this study, the variants C/G-13907 and T/G-13915, which are the major variants among the nomadic Arabs in the Arabia and Beja of East Africa, showed remarkable frequencies in Sudanese populations, especially those of pastoralists, in line with the historical links and bidirectional migration of nomadic populations between Arabia and East Africa. The C/T-13910 variant, generally associated with European populations is uniquely present among the Fulani. These data indicate that a combination of socio-economic, ethnic and evolutionary factors converged to shape the genetic structure of lactase persistence in East African populations.
The Diverse Forms of Lactose Intolerance and the Putative Linkage to Several Cancers
Amiri, Mahdi; Diekmann, Lena; von Köckritz-Blickwede, Maren; Naim, Hassan Y.
2015-01-01
Lactase-phlorizin hydrolase (LPH) is a membrane glycoprotein and the only β-galactosidase of the brush border membrane of the intestinal epithelium. Besides active transcription, expression of the active LPH requires different maturation steps of the polypeptide through the secretory pathway, including N- and O-glycosylation, dimerization and proteolytic cleavage steps. The inability to digest lactose due to insufficient lactase activity results in gastrointestinal symptoms known as lactose intolerance. In this review, we will concentrate on the structural and functional features of LPH protein and summarize the cellular and molecular mechanism required for its maturation and trafficking. Then, different types of lactose intolerance are discussed, and the molecular aspects of lactase persistence/non-persistence phenotypes are investigated. Finally, we will review the literature focusing on the lactase persistence/non-persistence populations as a comparative model in order to determine the protective or adverse effects of milk and dairy foods on the incidence of colorectal, ovarian and prostate cancers. PMID:26343715
The Diverse Forms of Lactose Intolerance and the Putative Linkage to Several Cancers.
Amiri, Mahdi; Diekmann, Lena; von Köckritz-Blickwede, Maren; Naim, Hassan Y
2015-08-28
Lactase-phlorizin hydrolase (LPH) is a membrane glycoprotein and the only β-galactosidase of the brush border membrane of the intestinal epithelium. Besides active transcription, expression of the active LPH requires different maturation steps of the polypeptide through the secretory pathway, including N- and O-glycosylation, dimerization and proteolytic cleavage steps. The inability to digest lactose due to insufficient lactase activity results in gastrointestinal symptoms known as lactose intolerance. In this review, we will concentrate on the structural and functional features of LPH protein and summarize the cellular and molecular mechanism required for its maturation and trafficking. Then, different types of lactose intolerance are discussed, and the molecular aspects of lactase persistence/non-persistence phenotypes are investigated. Finally, we will review the literature focusing on the lactase persistence/non-persistence populations as a comparative model in order to determine the protective or adverse effects of milk and dairy foods on the incidence of colorectal, ovarian and prostate cancers.
Szilagyi, Andrew
2015-08-13
Dairy foods contain complex nutrients which interact with the host. Yet, evolution of lactase persistence has divided the human species into those that can or cannot digest lactose in adulthood. Such a ubiquitous trait has differential effects on humanity. The literature is reviewed to explore how the divide affects lactose handling by lactase non persistent persons. There are two basic differences in digesters. Firstly, maldigesters consume less dairy foods, and secondly, excess lactose is digested by colonic microflora. Lactose intolerance in maldigesters may occur with random lactose ingestion. However, lactose intolerance without maldigestion tends to detract from gaining a clear understanding of the mechanisms of symptoms formation and leads to confusion with regards to dairy food consumption. The main consequence of intolerance is withholding dairy foods. However, regular dairy food consumption by lactase non persistent people could lead to colonic adaptation by the microbiome. This process may mimic a prebiotic effect and allows lactase non persistent people to consume more dairy foods enhancing a favorable microbiome. This process then could lead to alterations in outcome of diseases in response to dairy foods in lactose maldigesters. The evidence that lactose is a selective human prebiotic is reviewed and current links between dairy foods and some diseases are discussed within this context. Colonic adaptation has not been adequately studied, especially with modern microbiological techniques.
Szilagyi, Andrew
2015-01-01
Dairy foods contain complex nutrients which interact with the host. Yet, evolution of lactase persistence has divided the human species into those that can or cannot digest lactose in adulthood. Such a ubiquitous trait has differential effects on humanity. The literature is reviewed to explore how the divide affects lactose handling by lactase non persistent persons. There are two basic differences in digesters. Firstly, maldigesters consume less dairy foods, and secondly, excess lactose is digested by colonic microflora. Lactose intolerance in maldigesters may occur with random lactose ingestion. However, lactose intolerance without maldigestion tends to detract from gaining a clear understanding of the mechanisms of symptoms formation and leads to confusion with regards to dairy food consumption. The main consequence of intolerance is withholding dairy foods. However, regular dairy food consumption by lactase non persistent people could lead to colonic adaptation by the microbiome. This process may mimic a prebiotic effect and allows lactase non persistent people to consume more dairy foods enhancing a favorable microbiome. This process then could lead to alterations in outcome of diseases in response to dairy foods in lactose maldigesters. The evidence that lactose is a selective human prebiotic is reviewed and current links between dairy foods and some diseases are discussed within this context. Colonic adaptation has not been adequately studied, especially with modern microbiological techniques. PMID:26287234
Schultheis, Patrick J; Bowling, Bethany V
2011-01-01
Recent experimental evidence indicates that the ability of adults to tolerate milk, cheese, and other lactose-containing dairy products is an autosomal dominant trait that co-evolved with dairy farming in Central Europe about 7,500 years ago. Among persons of European descent, this trait is strongly associated with a C to T substitution at a polymorphic site 13,910 bp upstream of the lactase gene. This mutation results in the persistent expression of lactase into adulthood enabling individuals carrying a T(-13,910) allele to digest lactose as adults. In this report, we describe a laboratory exercise for an undergraduate molecular biology course in which students determine their own genotype at the -13,910 polymorphic site and correlate this with their ability to tolerate dairy products. The exercise is used as a tool to teach basic molecular biology procedures such as agarose gel electrophoresis, PCR1, and DNA sequencing. Students are actively engaged in the learning process, not only by analyzing their own DNA but also by applying their knowledge and skills to answer an authentic question. The exercise is also integrated with lecture material on the control of gene expression at the transcriptional level, in particular, how transcription factors can influence the activity of a promoter by binding to cis-acting DNA regulatory elements located within the proximal promoter of a gene or distant enhancer regions. Copyright © 2010 Wiley Periodicals, Inc.
Genetic Origins of Lactase Persistence and the Spread of Pastoralism in Africa
Ranciaro, Alessia; Campbell, Michael C.; Hirbo, Jibril B.; Ko, Wen-Ya; Froment, Alain; Anagnostou, Paolo; Kotze, Maritha J.; Ibrahim, Muntaser; Nyambo, Thomas; Omar, Sabah A.; Tishkoff, Sarah A.
2014-01-01
In humans, the ability to digest lactose, the sugar in milk, declines after weaning because of decreasing levels of the enzyme lactase-phlorizin hydrolase, encoded by LCT. However, some individuals maintain high enzyme amounts and are able to digest lactose into adulthood (i.e., they have the lactase-persistence [LP] trait). It is thought that selection has played a major role in maintaining this genetically determined phenotypic trait in different human populations that practice pastoralism. To identify variants associated with the LP trait and to study its evolutionary history in Africa, we sequenced MCM6 introns 9 and 13 and ∼2 kb of the LCT promoter region in 819 individuals from 63 African populations and in 154 non-Africans from nine populations. We also genotyped four microsatellites in an ∼198 kb region in a subset of 252 individuals to reconstruct the origin and spread of LP-associated variants in Africa. Additionally, we examined the association between LP and genetic variability at candidate regulatory regions in 513 individuals from eastern Africa. Our analyses confirmed the association between the LP trait and three common variants in intron 13 (C-14010, G-13907, and G-13915). Furthermore, we identified two additional LP-associated SNPs in intron 13 and the promoter region (G-12962 and T-956, respectively). Using neutrality tests based on the allele frequency spectrum and long-range linkage disequilibrium, we detected strong signatures of recent positive selection in eastern African populations and the Fulani from central Africa. In addition, haplotype analysis supported an eastern African origin of the C-14010 LP-associated mutation in southern Africa. PMID:24630847
Zheng, X; Chu, H; Cong, Y; Deng, Y; Long, Y; Zhu, Y; Pohl, D; Fried, M; Dai, N; Fox, M
2015-08-01
Many patients complain of abdominal symptoms with dairy products; however, clinical and psychosocial factors associated with self-reported lactose intolerance (SLI) have not been assessed in large studies. In particular, data are lacking from lactase deficient populations. This prospective cohort study assessed the prevalence of, and risk factors for, SLI in Chinese patients attending a gastroenterology clinic. Consecutive patients completed questionnaires to assess digestive health (Rome III), psychological state (HADS), life event stress (LES), food intake, and quality-of-life (SF-8). A representative sample completed genetic studies and hydrogen breath testing (HBT) at the clinically relevant dose of 20 g lactose. SLI was present in 411/910 (45%) clinic patients with functional abdominal symptoms. The genotype in all subjects was C/C-13910. A small number of novel SNPs in lactase promoter region were identified, including C/T-13908 which appeared to confer lactase persistence. Over half of the patients (54%) completed the 20 g lactose HBT with 58% (285/492) reporting typical symptoms. Positive and negative predictive values of SLI for abdominal symptoms during HBT were 60% and 44%, respectively. Psychological state and stress were not associated with SLI in clinic patients. SLI impacted on physical quality-of-life and was associated with reduced ingestion of dairy products, legumes, and dried fruit (p ≤ 0.05). In a lactase deficient population, approximately half of patients attending clinic with functional gastrointestinal symptoms reported intolerance to dairy products; however, SLI did not predict findings on 20 g lactose HBT. Independent of psychosocial factors, SLI impacted on quality-of-life and impacted on food choices with restrictions not limited to dairy products. © 2015 John Wiley & Sons Ltd.
Heine, Ralf G; AlRefaee, Fawaz; Bachina, Prashant; De Leon, Julie C; Geng, Lanlan; Gong, Sitang; Madrazo, José Armando; Ngamphaiboon, Jarungchit; Ong, Christina; Rogacion, Jossie M
2017-01-01
Lactose is the main carbohydrate in human and mammalian milk. Lactose requires enzymatic hydrolysis by lactase into D-glucose and D-galactose before it can be absorbed. Term infants express sufficient lactase to digest about one liter of breast milk daily. Physiological lactose malabsorption in infancy confers beneficial prebiotic effects, including the establishment of Bifidobacterium-rich fecal microbiota. In many populations, lactase levels decline after weaning (lactase non-persistence; LNP). LNP affects about 70% of the world's population and is the physiological basis for primary lactose intolerance (LI). Persistence of lactase beyond infancy is linked to several single nucleotide polymorphisms in the lactase gene promoter region on chromosome 2. Primary LI generally does not manifest clinically before 5 years of age. LI in young children is typically caused by underlying gut conditions, such as viral gastroenteritis, giardiasis, cow's milk enteropathy, celiac disease or Crohn's disease. Therefore, LI in childhood is mostly transient and improves with resolution of the underlying pathology. There is ongoing confusion between LI and cow's milk allergy (CMA) which still leads to misdiagnosis and inappropriate dietary management. In addition, perceived LI may cause unnecessary milk restriction and adverse nutritional outcomes. The treatment of LI involves the reduction, but not complete elimination, of lactose-containing foods. By contrast, breastfed infants with suspected CMA should undergo a trial of a strict cow's milk protein-free maternal elimination diet. If the infant is not breastfed, an extensively hydrolyzed or amino acid-based formula and strict cow's milk avoidance are the standard treatment for CMA. The majority of infants with CMA can tolerate lactose, except when an enteropathy with secondary lactase deficiency is present.
Petruski-Ivleva, Natalia; Kucharska-Newton, Anna; Palta, Priya; Couper, David; Meyer, Katie; Graff, Misa; Haring, Bernhard; Sharrett, Richey; Heiss, Gerardo
2017-10-17
Background : Faster rates of cognitive decline are likely to result in earlier onset of cognitive impairment and dementia. d-galactose, a derivative of lactose, is used in animal studies to induce neurodegeneration. Milk is the primary source of lactose in the human diet, and its effects on cognitive decline have not been fully evaluated. Objective : Assess the association of milk intake with change in cognitive function over 20 years. Methods : A total of 13,751 participants of the Atherosclerosis Risk in Communities (ARIC) cohort completed a food frequency questionnaire and three neurocognitive evaluations from 1990 through 2013. Two single nucleotide polymorphisms (SNPs) were used to determine lactase persistence (LCT-13910 C/T for Whites and LCT-14010 G/C for Blacks). Mixed-effects models were used to study the association of milk intake with cognitive change. Multiple imputations by chained equations were used to account for attrition. Results : Milk intake greater than 1 glass/day was associated with greater decline in the global z-score over a 20-year period. The difference in decline was 0.10 (95% CI: 0.16, 0.03) z-scores, or an additional 10% decline, relative to the group reporting "almost never" consuming milk. Conclusions : Replication of these results is warranted in diverse populations with greater milk intake and higher variability of lactase persistence genotype.
Petruski-Ivleva, Natalia; Kucharska-Newton, Anna; Palta, Priya; Meyer, Katie; Graff, Misa; Haring, Bernhard; Sharrett, Richey; Heiss, Gerardo
2017-01-01
Background: Faster rates of cognitive decline are likely to result in earlier onset of cognitive impairment and dementia. d-galactose, a derivative of lactose, is used in animal studies to induce neurodegeneration. Milk is the primary source of lactose in the human diet, and its effects on cognitive decline have not been fully evaluated. Objective: Assess the association of milk intake with change in cognitive function over 20 years. Methods: A total of 13,751 participants of the Atherosclerosis Risk in Communities (ARIC) cohort completed a food frequency questionnaire and three neurocognitive evaluations from 1990 through 2013. Two single nucleotide polymorphisms (SNPs) were used to determine lactase persistence (LCT-13910 C/T for Whites and LCT-14010 G/C for Blacks). Mixed-effects models were used to study the association of milk intake with cognitive change. Multiple imputations by chained equations were used to account for attrition. Results: Milk intake greater than 1 glass/day was associated with greater decline in the global z-score over a 20-year period. The difference in decline was 0.10 (95% CI: 0.16, 0.03) z-scores, or an additional 10% decline, relative to the group reporting “almost never” consuming milk. Conclusions: Replication of these results is warranted in diverse populations with greater milk intake and higher variability of lactase persistence genotype. PMID:29039795
From 'lactose intolerance' to 'lactose nutrition'.
Lukito, Widjaja; Malik, Safarina G; Surono, Ingrid S; Wahlqvist, Mark L
2015-01-01
The concept of lactose intolerance has become embedded in Western medicine and developing economy medicine. It is based on evidence that intestinal lactase activity persists into later childhood and throughout life in only a minority of the world's population, notably northern European-derived populations. These people have the T single nucleotide polymorphism (SNP) of the rs49882359 allele (C/T), also known as C/T-13910, the MCM6 gene which positively influences the lactase LCT gene. Other lactase persistent (LP) populations are found in Africa and the Middle East with different genetic variants. These SNPs represent co-evolution with dairying since the agricultural revolution and nutrient-dependent ecological adaptation. That said, gastrointestinal symptoms considered due to small intestinal lactose malabsorption are poorly correlated with lactase non-persistence (LNP), the situation for most people. With LNP, colonic microbiome lactase enables lactose fermentation to occur so that none is found in faeces. Whether the short chain fatty acids (SCFAs) and gases (hydrogen, carbon dioxide and methane) produced cause symptoms is dose-dependent. Up to 25 g of lactose at any one time can usually be consumed by a LNP person, but its food and meal pattern context, the microbiomic characteristics, age and other factors may alter tolerance. Thus, the notion that lactose intolerance is a disorder or disease of LNP people is misplaced and has been one of cultural perspective. What actually matters is whether a particular dairy product as normally consumed give rise to symptoms. It is, therefore, proposed that lactose tolerance tests be replaced with dairy food tolerance tests.
Positive selection of lactase persistence among people of Southern Arabia.
Bayoumi, Riad; De Fanti, Sara; Sazzini, Marco; Giuliani, Cristina; Quagliariello, Andrea; Bortolini, Eugenio; Boattini, Alessio; Al-Habori, Molham; Al-Zubairi, Adel Sharaf; Rose, Jeffrey I; Romeo, Giovanni; Al-Abri, Abdulrahim; Luiselli, Donata
2016-12-01
Frequency patterns of the lactase persistence (LP)-associated -13,915 G allele and archaeological records pointing to substantial role played by southern regions in the peopling and domestication processes that involved the Arabian Peninsula suggest that Southern Arabia plausibly represented the center of diffusion of such adaptive variant. Nevertheless, a well-defined scenario for evolution of Arabian LP is still to be elucidated and the burgeoning archaeological picture of complex human migrations occurred through the peninsula is not matched by an equivalent high-resolution description of genetic variation underlying this adaptive trait. To fill this gap, we investigated diversity at a wide genomic interval surrounding the LCT gene in different Southern Arabian populations. 40 SNPs were genotyped to characterize LCT profiles of 630 Omani and Yemeni individuals to perform population structure, linkage disequilibrium, population differentiation-based and haplotype-based analyses. Typical Arabian LP-related variation was found in Dhofaris and Yemenis, being characterized by private haplotypes carrying the -13,915 G allele, unusual differentiation with respect to northern groups and conserved homozygous haplotype-blocks, suggesting that the adaptive allele was likely introduced in the Arabian gene pool in southern populations and was then subjected to prolonged selective pressure. By pointing to Yemen as one of the best candidate centers of diffusion of the Arabian-specific adaptive variant, obtained results indicate the spread of indigenous groups as the main process underlying dispersal of LP along the Arabian Peninsula, supporting a refugia model for Arabian demic movements occurred during the Terminal Pleistocene and Early Holocene. © 2016 Wiley Periodicals, Inc.
Gene–Dairy Food Interactions and Health Outcomes: A Review of Nutrigenetic Studies
Pasin, Gonca
2017-01-01
Each person differs from the next by an average of over 3 million genetic variations in their DNA. This genetic diversity is responsible for many of the interindividual differences in food preferences, nutritional needs, and dietary responses between humans. The field of nutrigenetics aims to utilize this type of genetic information in order to personalize diets for optimal health. One of the most well-studied genetic variants affecting human dietary patterns and health is the lactase persistence mutation, which enables an individual to digest milk sugar into adulthood. Lactase persistence is one of the most influential Mendelian factors affecting human dietary patterns to occur since the beginning of the Neolithic Revolution. However, the lactase persistence mutation is only one of many mutations that can influence the relationship between dairy intake and disease risk. The purpose of this review is to summarize the available nutrigenetic literature investigating the relationships between genetics, dairy intake, and health outcomes. Nonetheless, the understanding of an individual’s nutrigenetic responses is just one component of personalized nutrition. In addition to nutrigenetic responses, future studies should also take into account nutrigenomic responses (epigenomic, transcriptomic, proteomic, metabolomic), and phenotypic/characteristic traits (age, gender, activity level, disease status, etc.), as these factors all interact with diet to influence health. PMID:28684688
Pruimboom, Leo; Fox, Tom; Muskiet, Frits A J
2014-03-01
Various positively selected adaptations to new nutrients have been identified. Lactase persistence is among the best known, conferring the ability for drinking milk at post weaning age. An augmented number of amylase gene (AMY1) copies, giving rise to higher salivary amylase activity, has been implicated in the consumption of starch-rich foods. Higher AMY1 copy numbers have been demonstrated in populations with recent histories of starchy-rich diets. It is however questionable whether the resulting polymorphisms have exerted positive selection only by providing easily available sources of macro and micronutrients. Humans have explored new environments more than any other animal. Novel environments challenge the host, but especially its immune system with new climatic conditions, food and especially pathogens. With the advent of the agricultural revolution and the concurrent domestication of cattle came new pathogens. We contend that specific new food ingredients (e.g., gluten) and novel pathogens drove selection for lactase persistence and higher AMY gene copy numbers. Both adaptations provide ample glucose for activating the sodium glucose-dependent co-transporter 1 (SGLT1), which is the principal glucose, sodium and water transporter in the gastro-intestinal tract. Their rapid uptake confers protection against potentially lethal dehydration, hyponatremia and ultimately multiple organ failure. Oral rehydration therapy aims at SGLT1 activity and is the current treatment of choice for chronic diarrhoea and vomiting. We hypothesize that lifelong lactase activity and rapid starch digestion should be looked at as the evolutionary covalent of oral rehydration therapy. Copyright © 2014 Elsevier Ltd. All rights reserved.
The relationship between the human genome and microbiome comes into view
Goodrich, Julia K.; Davenport, Emily R.; Clark, Andrew G.; Ley, Ruth E.
2017-01-01
The microbiome’s involvement in health and disease, and the complexity of its composition and function, make it intriguing to consider human genetic factors that impact microbiome composition. Genes may influence health through their ability to promote a stable microbial community in the gut. Studies of heritability yield a consistent subset of microbes that are impacted by genes, but the use of genome-wide association studies (GWAS) to identify specific genetic variants associated with microbiota phenotypes has proven challenging. Processing microbiome datasets into traits to be modeled and reducing the burden of multiple testing are just some of the technical hurdles in microbiome GWAS. Studies to date are small by GWAS standards, making cross-study comparisons and validations particularly important in identifying authentic signals. Cross-study comparisons are hampered by differences in analytical approaches. Nevertheless, some consistent associations have emerged between populations, most notably between Bifidobacteria and the lactase non-persister genotype. These early successes open the way for the microbiome to be incorporated into studies that quantify interactions among genotype, environment, and the microbiome for predicting disease susceptibility. PMID:28934590
Szilagyi, Andew; Xue, Xiaoqing
2016-11-01
Geographic patterns with diminishing rates from north to south toward the equator have been described for a number of diseases, putatively related largely to "western" lifestyle. Among these the inflammatory bowel diseases; Crohn's (CD) and Ulcerative colitis (UC) have been prominent in sharing distributions with a number of autoimmune diseases. One of the interesting associations is the epidemiologic similarity with multiple sclerosis (MS). However, in addition, at least some of these diseases also correlated inversely with lactase non persistent population (LNP) distributions. It is hypothesized that MS should also have an inverse relationship with LNP. We provide support for this by comparing published MS, CD, UC and LNP national rates to the beginning of the new millennium. Possible links among these diseases may be an evolutionary signature of new genes which may have accompanied emergence of lactase persistence millennia ago. The emergent phenotypic dichotomy also forced different assimilation responses to lactose digestion. While intestinal retention of lactase results in direct host enzymatic digestion, in LNP persons intestinal bacterial metabolism of lactose impacts on the host micro-flora. These microbial changes may play some role in altering rates of diseases including IBD and MS. However, since the late 20th century previously observed patterns are changing. Although industrialization is considered to play an important modifying role, the rising rates of obesity with an emphasis on diet, and microfloral pathogenesis, but with an independent geographic pattern may also facilitate altering rates and geographic distributions of both of these and other diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.
[Lactose intolerance: past and present. Part II].
Buzás, György Miklós
2015-10-25
The author summarises the interrelations between lactose intolerance, calcium and vitamin D metabolism and osteoporosis. Lactose intolerance enhances the risk of forearm and hip fractures in some patients. Lactase gene genotype and fracture risk are related in some populations. Calcium and vitamin D supplementation increase bone mineral content and they are justified in children, during pregnancy and lactation, and in postmenopausal women. The intake of milk and milk products could increase the risk of ovarian carcinoma. CC genotype of the lactase gene increased the risk of colorectal carcinoma in Finns; no such effect was observed in British, Spanish and Italian patients. Even small quantities of lactose in drugs (10-750 mg) could elicit intolerance symptoms due to individual susceptibility. In spite of public knowledge and advertising, controlled studies did not prove the beneficial effect of either a lactose-free diet, enzyme supplementation or probiotics in an evidence-based manner. While accepted guidelines are lacking, a personalised therapy is mandatory. In spite of increasing public interest in lactose intolerance, many unknown factors must still be studied.
Liebert, Anke; López, Saioa; Jones, Bryony Leigh; Montalva, Nicolas; Gerbault, Pascale; Lau, Winston; Thomas, Mark G; Bradman, Neil; Maniatis, Nikolas; Swallow, Dallas M
2017-11-01
The genetic trait of lactase persistence (LP) is associated with at least five independent functional single nucleotide variants in a regulatory region about 14 kb upstream of the lactase gene [-13910*T (rs4988235), -13907*G (rs41525747), -13915*G (rs41380347), -14009*G (rs869051967) and -14010*C (rs145946881)]. These alleles have been inferred to have spread recently and present-day frequencies have been attributed to positive selection for the ability of adult humans to digest lactose without risk of symptoms of lactose intolerance. One of the inferential approaches used to estimate the level of past selection has been to determine the extent of haplotype homozygosity (EHH) of the sequence surrounding the SNP of interest. We report here new data on the frequencies of the known LP alleles in the 'Old World' and their haplotype lineages. We examine and confirm EHH of each of the LP alleles in relation to their distinct lineages, but also show marked EHH for one of the older haplotypes that does not carry any of the five LP alleles. The region of EHH of this (B) haplotype exactly coincides with a region of suppressed recombination that is detectable in families as well as in population data, and the results show how such suppression may have exaggerated haplotype-based measures of past selection.
Hartwig, Fernando Pires; Horta, Bernardo Lessa; Smith, George Davey; de Mola, Christian Loret; Victora, Cesar Gomes
2016-10-01
Milk intake has been associated with lower blood pressure (BP) in observational studies, and randomized controlled trials suggested that milk-derived tripeptides have BP-lowering effects. Milk intake has also been associated with body mass index (BMI). Nevertheless, it is unclear whether increasing milk consumption would reduce BP in the general population. We investigated the association of milk intake with obesity and BP using genetically-defined lactase persistence (LP) based on the rs4988235 polymorphism in a Mendelian randomization design in the 1982 Pelotas (Southern Brazil) Birth Cohort. These results were combined with published reports identified through a systematic review using meta-analysis. In the 1982 Pelotas Birth Cohort, milk intake was 42 [95% confidence interval (CI): 18; 67) ml/day higher in LP individuals. In conventional observational analysis, each 1-dl/day increase in milk intake was associated with -0.26 (95% CI: -0.33; -0.19) kg/m 2 in BMI and -0.31 (95% CI: -0.46; -0.16) and -0.35 (95% CI: -0.46; -0.23) mmHg in systolic and diastolic BP, respectively. These results were not corroborated when analysing LP status, but confidence intervals were large. In random effects meta-analysis, LP individuals presented higher BMI [0.17 (95% CI: 0.07; 0.27) kg/m 2 ] and higher odds of overweight-obesity [1.09 (95% CI: 1.02; 1.17)]. There were no reliable associations for BP. Our study supports that LP is positively associated with obesity, suggesting that the negative association of milk intake with obesity is likely due to limitations of conventional observational studies. Our findings also do not support that increased milk intake leads to lower BP. © The Author 2016. Published by Oxford University Press on behalf of the International Epidemiological Association.
Prevalence of lactose intolerance in Chile: a double-blind placebo study.
Latorre, Gonzalo; Besa, Pablo; Parodi, Carmen G; Ferrer, Verónica; Azocar, Lorena; Quirola, Marife; Villarroel, Luis; Miquel, Juan F; Agosin, Eduardo; Chianale, José
2014-01-01
Lactase non-persistence (LNP), or primary hypolactasia, is a genetic condition that mediates lactose malabsorption and can cause lactose intolerance. Here we report the prevalence of lactose intolerance in a double-blind placebo study. The LCT C>T-13910 variant was genotyped by RT-PCR in 121 volunteers and lactose malabsorption was assessed using the hydrogen breath test (HBT) after consuming 25 g of lactose. Lactose intolerance was assessed by scoring symptoms (SS) using a standardized questionnaire following challenge with a lactose solution or saccharose placebo. The LNP genotype was observed in 57% of the volunteers, among whom 87% were HBT⁺. In the HBT⁺ group the median SS was 9 and in the HBT⁻ group the median SS was 3 (p < 0.001). No difference was observed in the SS when both groups were challenged with the placebo. The most common symptoms included audible bowel sounds, abdominal pain and meteorism. In the ROC curve analysis, an SS ≥ 6 demonstrated 72% sensitivity and 81% specificity for predicting a positive HBT. To estimate prevalence, lactose intolerance was defined as the presence of an SS ≥ 6 points after subtracting the placebo effect and 34% of the study population met this definition. The LNP genotype was present in more than half of subjects evaluated and the observed prevalence of lactose intolerance was 34%. © 2014 S. Karger AG, Basel.
Mild CFTR mutations and genetic predisposition to lactase persistence in cystic fibrosis
Mądry, Edyta; Fidler, Ewa; Sobczyńska-Tomaszewska, Agnieszka; Lisowska, Aleksandra; Krzyżanowska, Patrycja; Pogorzelski, Andrzej; Minarowski, Łukasz; Oralewska, Beata; Mojs, Ewa; Sapiejka, Ewa; Marciniak, Ryszard; Sands, Dorota; Korzon-Burakowska, Anna; Kwiecień, Jarosław; Walkowiak, Jarosław
2011-01-01
Taking into account the reported incidence of hypolactasia in cystic fibrosis (CF) and the possible impact of milk products on nutritional status we aimed to assess the genetic predisposition to adult-type hypolactasia (ATH) and its incidence in CF. Single nucleotide polymorphism upstream of the lactase gene (LCT) was assessed in 289 CF patients. In subject with −13910C/C genotype (C/C) predisposing to ATH, hydrogen-methane breath test (BT) with lactose loading was conducted and clinical symptoms typical for lactose malabsorption were assessed. The percentage of CF patients with C/C was similar to that observed in healthy subjects (HS) (31.5 vs 32.5% ). Eleven out of 52 (24.5%) CF C/C patients had abnormal BT results. The recalculated frequency of lactose malabsorption was similar for the entire CF and HS populations (6.9 vs 7.2%). Similarly as in the control group, few CF patients have identified and linked to lactose consumption clinical symptoms. The frequency of LCT polymorphic variants in CF patients having and not having severe mutations of CFTR gene showed significant differences. The C allele was more frequent in homozygotes of the severe mutations than in patients carrying at least one mild/unknown mutation (P<0.0028) and in patients with at least one mild mutation (P<0.0377). In conclusion, CF patients carrying mild CFTR mutations seem to have lower genetic predisposition to ATH. Lactose malabsorption due to ATH in CF is not more frequent than in the general population. Symptomatic assessment of lactose malabsorption in CF is not reliable. PMID:21407263
Dairy consumption, systolic blood pressure, and risk of hypertension: Mendelian randomization study
USDA-ARS?s Scientific Manuscript database
Objective: To examine whether previous observed inverse associations of dairy intake with systolic blood pressure and risk of hypertension were causal. Design: Mendelian randomization study using the single nucleotide polymorphism rs4988235 related to lactase persistence as an instrumental variable...
Dairy consumption, systolic blood pressure, and risk of hypertension: Mendelian randomization study
USDA-ARS?s Scientific Manuscript database
This study examined whether previous observed inverse associations of dairy intake with systolic blood pressure and risk of hypertension were causal. A Mendelian randomization study was employed, using the single nucleotide polymorphism rs4988235 related to lactase persistence as an instrumental var...
Wong, Dana E; Talbert, Joey N; Goddard, Julie M
2013-06-01
Active packaging is utilized to overcome limitations of traditional processing to enhance the health, safety, economics, and shelf life of foods. Active packaging employs active components to interact with food constituents to give a desired effect. Herein we describe the development of an active package in which lactase is covalently attached to low-density polyethylene (LDPE) for in-package production of lactose-free dairy products. The specific goal of this work is to increase the total protein content loading onto LDPE using layer by layer (LbL) deposition, alternating polyethylenimine, glutaraldehyde (GL), and lactase, to enhance the overall activity of covalently attached lactase. The films were successfully oxidized via ultraviolet light, functionalized with polyethylenimine and glutaraldehyde, and layered with immobilized purified lactase. The total protein content increased with each additional layer of conjugated lactase, the 5-layer sample reaching up to 1.3 μg/cm2 . However, the increase in total protein did not lend to an increase in overall lactase activity. Calculated apparent Km indicated the affinity of immobilized lactase to substrate remains unchanged when compared to free lactase. Calculated apparent turnover numbers (kcat ) showed with each layer of attached lactase, a decrease in substrate turnover was experienced when compared to free lactase; with a decrease from 128.43 to 4.76 s(-1) for a 5-layer conjugation. Our results indicate that while LbL attachment of lactase to LDPE successfully increases total protein mass of the bulk material, the adverse impact in enzyme efficiency may limit the application of LbL immobilization chemistry for bioactive packaging use. © 2013 Institute of Food Technologists®
ERIC Educational Resources Information Center
Schultheis, Patrick J.; Bowling, Bethany V.
2011-01-01
Recent experimental evidence indicates that the ability of adults to tolerate milk, cheese, and other lactose-containing dairy products is an autosomal dominant trait that co-evolved with dairy farming in Central Europe about 7,500 years ago. Among persons of European descent, this trait is strongly associated with a C to T substitution at a…
Szilagyi, Andrew; Xue, Xiaoqing
2018-01-01
Irritable Bowel Syndrome (IBS) shares overlapping symptoms and some features of pathogenesis with Inflammatory Bowel Diseases (IBD: Crohn's disease [CD], and Ulcerative Colitis [UC]). Geographic markers such as latitude/sunshine and more recently lactase population distributions are found to be correlated with IBD. As a result of clinical and pathogenic similarities between the 2 conditions, some authorities questioned whether a connection exists between them. We compare IBS directly with IBD, and indirectly with geographic markers associated with IBD, in order to evaluate possible evolutionary links between IBS and IBD. Similar correlations may link IBS as a precursor to IBD and possibly other conditions which are geographically connected with IBD. Data from four systematic reviews on IBD incidence and prevalence, IBS prevalence, and lactase distributions were included. Pearson's correlations were used for comparisons, with IBD values log-transformed because of skewed distribution. The articles provided 18-28 complete set of national data. Direct comparison between IBS and IBD showed no significant correlations (r = -0.14, r = -0.06 for CD and UC prevalence, r = -0.10 for CD incidence). Indirect comparisons also failed to show correlations of IBS with lactase distributions (r = -0.17), sunshine (r = -0.2) or latitude (r = 0.097); however, there was significant correlation between lactase distributions and CD incidence (r = -0.84), prevalence (r = -0.55) and UC prevalence (r = -0.59). Both sunshine (r= -0.53) and latitude (r = 0.58) are also significantly related to CD incidence. It is concluded that IBS and IBD do not follow similar global geographic patterns. This suggests a lack of an evolutionary genetic background coincident with emergence of lactase persistence. As well, vitamin D has no obvious impact on development of IBS. Similarities with IBD may result from sub groups (not yet identified) within the current Rome criteria of IBS. Alternatively limited intestinal gut-brain responses to host microbial interactions may result in similar overlap features in both. Copyright © 2017 Elsevier Ltd. All rights reserved.
Lactose intolerance: diagnosis, genetic, and clinical factors
Mattar, Rejane; de Campos Mazo, Daniel Ferraz; Carrilho, Flair José
2012-01-01
Most people are born with the ability to digest lactose, the major carbohydrate in milk and the main source of nutrition until weaning. Approximately 75% of the world’s population loses this ability at some point, while others can digest lactose into adulthood. This review discusses the lactase-persistence alleles that have arisen in different populations around the world, diagnosis of lactose intolerance, and its symptomatology and management. PMID:22826639
de Vrese, Michael; Laue, Christiane; Offick, Birte; Soeth, Edlyn; Repenning, Frauke; Thoß, Angelika; Schrezenmeir, Jürgen
2015-06-01
Lactose digestion can be improved in subjects with impaired or completely absent intestinal lactase activity by administration of lactase preparations and particularly of acid lactase, which is active in the stomach, or by yogurt containing live lactic acid bacteria. It is the question, if lactose digestion can be further enhanced by combining these two approaches. We investigated in a randomised, placebo-controlled, double-blind, 5-arm crossover study on 24 lactose malabsorbers with variable degrees of lactase deficiency if different lactase preparations and freeze-dried yogurt culture affect gastrointestinal lactose digestion after consuming moderate amounts of lactose (12.5 g) by assessing hydrogen exhalation over 6 h. Furthermore, symptoms of lactose intolerance (excess gas production, abdominal pain, diarrhoea or nausea) were assessed using validated questionnaires. All preparations increased lactose digestion and reduced peak hydrogen exhalation by -27% (yogurt), -29/-33% (3300/9000 FCC(1) ((1) One FCC hydrolyses about 5 or 1.7-2.5 mg lactose in aquous solution or in (artificial) chyme, respectively, according to the FCC-III method of the Committee on Codex Specifications, Food and Nutrition Board, National Research Council. Food Chemicals Codex, 3rd edition. Washington, DC, National Academy Press, 1981 It cannot precisely be defined how much lactose can be hydrolysed in vivo by the consumption of a certain number of FCC units.) units acid lactase from Aspergillus oryzae) or -46%, respectively (3300 FCC units lactase plus yogurt culture combined), as compared with placebo (p < 0.001, Friedman test). The combination preparation had not only the strongest effect, but also showed the lowest variance in H(2)-exhalation values (less malabsorbers with no reduction of H(2)-exhalation) Apart from this, both the higher dose lactase and the combination preparation significantly reduced the symptoms most closely associated with H(2)-exhalation, namely flatulences and abdominal pain, respectively. The combined administration of freeze-dried yogurt cultures and acid lactase increases lactose digestion more than either freeze-dried yogurt cultures or acid lactase alone, and more lactose malabsorbers benefited from this effect. Copyright © 2014. Published by Elsevier Ltd.
21 CFR 184.1387 - Lactase enzyme preparation from Candida pseudotropicalis.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Lactase enzyme preparation from Candida... Specific Substances Affirmed as GRAS § 184.1387 Lactase enzyme preparation from Candida pseudotropicalis. (a) This enzyme preparation is derived from the nonpathogenic, nontoxicogenic yeast C...
Immobilization of Lactase onto Various Polymer Nanofibers for Enzyme Stabilization and Recycling.
Jin, Lihua; Li, Ye; Ren, Xiang-Hao; Lee, Jung-Heon
2015-08-01
Five different polymer nanofibers, namely, polyaniline nanofiber (PANI), magnetically separable polyaniline nanofiber (PAMP), magnetically separable DEAE cellulose fiber (DEAE), magnetically separable CM cellulose fiber (CM), and polystyrene nanofiber (PSNF), have been used for the immobilization of lactase (E.C. 3.2.1.23). Except for CM and PSNF, three polymers showed great properties. The catalytic activities (kcat) of the free, PANI, PAMP, and magnetic DEAE-cellulose were determined to be 4.0, 2.05, 0.59, and 0.042 mM/min·mg protein, respectively. The lactase immobilized on DEAE, PANI, and PAMP showed improved stability and recyclability. PANI- and PAMP-lactase showed only a 0-3% decrease in activity after 3 months of vigorous shaking conditions (200 rpm) and at room temperature (25°C). PANI-, PAMP-, and DEAE-lactase showed a high percentage of conversion (100%, 47%, and 12%) after a 1 h lactose hydrolysis reaction. The residual activities of PANI-, PAMP-, and DEAE-lactase after 10 times of recycling were 98%, 96%, and 97%, respectively.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hoff, T.; Liu, S.Y.; Bollag, J.M.
1985-05-01
The lactase of the fungus Trametes versicolor was able to polymerize various halogen-, alkyl-, and alkoxy-substituted anilines, showing substrate specificity similar to that of horseradish peroxidase, whereas the lactase of Rhizoctonia praticola was active only with p-methoxyaniline. The substrate specificities of the enzymes were determined by using gas chromatography to measure the decrease in substrate concentration during incubation. With p-chloroaniline as the substrate, the peroxidase and the Trametes lactase showed maximum activity near pH 4.2. The transformation of this substrate gave rise to a number of oligomers, ranging from dimers to pentamers, as determined by mass spectrometry. The product profilesmore » obtained by high-pressure liquid chromatography were similar for the two enzymes. A chemical reaction was observed between p-chloroaniline and an enzymatically formed dimer, resulting in the formation of a trimer. All three enzymes oxidized p-methoxyaniline to 2-amino-5-p-anisidinobenzoquinone di-p-methoxyphenylimine, but only the T. versicolor lactase and the peroxidase caused the formation of a pentamer (2,5-di-p-anisidinobenzoquinone di-p-methoxyphenylimine). These results demonstrate that in addition to horseradish peroxidase, a T. versicolor lactase can also polymerize aniline derivatives.« less
Dairy foods and health in Asians: Taiwanese considerations.
Lee, Meei-Shyuan; Wahlqvist, Mark L; Peng, Cheau-Jane
2015-01-01
The health relevance of dairy products has mostly been judged by their abundant nutrients (protein, calcium and riboflavin) and recommendations for these derived in lactase-persistent Caucasian populations. Extrapolation to Asians who are generally lactase non-persisters may not be biologically, culturally or environmentally sound. A number of studies, especially among north-east Asians as in Taiwan, provide guidance for their optimal dairy intakes. In Taiwan, the NAHSIT (Nutrition and Health Surveys in Taiwan) linked to the National Health Insurance and Death Registry data bases provide most of the evidence. Cultural and socio-economic barriers create population resistance to increase dairy consumption beyond one serving per day as reflected in food balance sheet and repeat survey trend analyses. For the morbidity and mortality patterns principally seen in Asia, some, but not too much, dairy is to be preferred. This applies to all-cause and cardiovascular, especially stroke, mortality, to the risk of overfatness (by BMI and abdominal circumference) and diabetes and very likely to fracture and its sequelae. In Taiwan, there is no apparent association with total cancer mortality, but among Europeans, there may be protection. Historically, while fermented mammalian milks have been consumed in south Asia and various Asian subgroups and regions, most of the uptake of dairy in Asia after World War 2 has been from imported powdered milk or fresh liquid milk, encouraged further by the use of yogurts and popularization of milk teas and coffee. Asian dietary guidelines and clinical nutrition protocols need to encourage a modest, asymptomatic dairy intake.
Lactase persistence variants in Arabia and in the African Arabs.
Priehodová, Edita; Abdelsawy, Abdelhay; Heyer, Evelyne; Cerný, Viktor
2014-01-01
Lactase persistence (LP), the state enabling the digestion of milk sugar in adulthood, occurs only in some human populations. The convergent and independent origin of this physiological ability in Europe and Africa is linked with animal domestication that either had started in both places independently or had spread from the Near East by acculturation. However, it has recently been shown that at least in its southern parts, the population of Arabia not only has a different LP-associated mutation profile than the rest of Africa and Europe but also had experienced an independent demographic expansion occurring before the Neolithic around the Pleistocene-Holocene boundary. In Arabia, LP is associated with mutation -13,915*G and not, as in Europe, with -13,910*T or, as in Africa, with -13,907*G and -14,010*C. We show here that, in Arabia, -13,915*G frequency conforms to a partial clinal pattern and that this specific mutation has likely been spread from Arabia to Africa only recently from the sixth century AD onward by nomadic Arabs (Bedouins) looking for new pastures. Arabic populations in Africa that still maintain a nomadic way of life also have more -13,915*G variants and fewer sub-Saharan L-type mitochondrial DNA haplogroups; this observation matches archaeological and historical records suggesting that the migration of Arabic pastoralists was accompanied by gradual sedentarization that allowed for admixture with the local African population. Copyright © 2014 Wayne State University Press, Detroit, Michigan 48201-1309.
Wu, Yougen; Li, Yinghua; Cui, Yunqing; Zhou, Yunjiao; Qian, Qingqing; Hong, Yang
2017-12-01
A number of studies have investigated the association of lactase (LCT,C/T-13910) gene polymorphismwith bonemineral density (BMD) and fracture risk, but previous results were inconclusive. In this study, a meta-analysis was performed to quantify the association of LCT (C/T-13910) polymorphism with BMD and fracture risk. Eligible publications were searched in the PubMed, Web of Science, Embase databases, Google Scholar, Yahoo and Baidu. Pooled weighed mean difference (WMD) or odds ratio (OR) with their 95% confidence interval (CI) were calculated using a fixed-effects or random-effects model. A total of nine articles with 8871 subjects were investigated in the presentmeta-analysis. Overall, the TT/TC genotypes of LCT 13910 C/T polymorphism showed significantly higher BMD than those with the CC genotype at femur neck (FN) (WMD = 0.011 g/cm 2 , 95% CI = 0.004-0.018, P = 0.003). Besides, LCT 13910 C/T polymorphism may decrease the risk of any site fractures (for TT versus TC+CC, OR = 0.813, 95% CI = 0.704-0.938, P = 0.005; for T allele versus C allele, OR = 0.885, 95% CI = 0.792-0.989, P = 0.032). However, there was no significant association of LCT 13910 C/T polymorphism with BMD at lumbar spine and risk of vertebral fractures under all genetic contrast models (all P values were >0.05). The meta-analysis suggests that there are significant effects of LCT 13910 C/T polymorphism on BMD and fracture risk. Large-scale studies with different ethnic populations will be needed to further investigate the possible race-specific effect of LCT 13910 C/T polymorphism on BMD and fracture risk.
Szilagyi, Andrew; Leighton, Henry; Burstein, Barry; Shrier, Ian
2011-01-01
Decreasing latitude and increasing frequency of population lactase nonpersistence have been reported to diminish risks for several diseases, but the reason for overlap has not been explained. We evaluate, relationships between calculated national annual ultraviolet light B (UVB) exposure, latitude, and national lactose digestion frequencies. Annual UVB exposure and latitude were based on weighted averages from several cities in different countries. Lactase distribution status was based on published data that have been used previously to derive relations with diseases. We compare univariate regression analyses (r(2)(adj), slope) of percentage of lactase nonpersistence with UVB or latitude. We determine, differences between European and non-European sources by multiregression analysis of independent variables. Correlation between UVB and latitude is high (r(2) = 0.89), and between percentage of lactase nonpersistence and either latitude or UVB the correlation is moderately strong with r(2) = 0.51 and 0.46, respectively, with P ≤ 0.01 for both. A more detailed analysis shows that correlations between percentage of lactase nonpersistence and UVB are only significant in Europe, r(2) = 0.59, P < 0.001, whereas outside Europe: r(2) = 0.06, P = 0.16. These relationships raise hypothetical explanations to account for the observed overlap in similar risk modification by the 2 variables.
Toxicological Evaluation of Lactase Derived from Recombinant Pichia pastoris
Liu, Yifei; Chen, Delong; Luo, Yunbo; Huang, Kunlun; Zhang, Wei; Xu, Wentao
2014-01-01
A recombinant lactase was expressed in Pichia pastoris, resulting in enzymatic activity of 3600 U/mL in a 5 L fermenter. The lactase product was subjected to a series of toxicological tests to determine its safety for use as an enzyme preparation in the dairy industry. This recombinant lactase had the highest activity of all recombinant strains reported thus far. Acute oral toxicity, mutagenicity, genotoxic, and subchronic toxicity tests performed in rats and mice showed no death in any groups. The lethal dose 50% (LD50) based on the acute oral toxicity study is greater than 30 mL/kg body weight, which is in accordance with the 1500 L milk consumption of a 50 kg human daily. The lactase showed no mutagenic activity in the Ames test or a mouse sperm abnormality test at levels of up to 5 mg/plate and 1250 mg/kg body weight, respectively. It also showed no genetic toxicology in a bone marrow cell micronucleus test at levels of up to 1250 mg/kg body weight. A 90-day subchronic repeated toxicity study via the diet with lactase levels up to 1646 mg/kg (1000-fold greater than the mean human exposure) did not show any treatment-related significant toxicological effects on body weight, food consumption, organ weights, hematological and clinical chemistry, or histopathology compared to the control groups. This toxicological evaluation system is comprehensive and can be used in the safety evaluation of other enzyme preparations. The lactase showed no acute, mutagenic, genetic, or subchronic toxicity under our evaluation system. PMID:25184300
Rossi, E; Lentze, M J
1984-12-01
The study of deficiencies of small intestinal brush-border hydrolases increased our knowledge about the specific functions of hydrolases in the digestion of smaller molecules on the microvillus surface of the absorptive cells. The sucrase-isomaltase (SI) complex has been shown to be synthesized as a precursor (pro-sucrase-isomaltase) which is then incorporated into the membrane. The hydrophobic N-terminal end of the molecule is anchored in the lipid bilayer. In SI deficiency the molecular base of the disease is still not clear. Absence of SI activity could be due to complete lack of precursor synthesis or to structural changes within the N-terminal end of the SI-complex. Deficiencies of peptide hydrolases have not been reported with the exception of enteropeptidase (EP). Here a congenital deficiency of the enzyme was observed as the primary defect in enzyme synthesis within the enterocytes and as a secondary defect due to exocrine pancreatic insufficiency. In contrast to the primary EP deficiency, the activity of EP can be restored in the cases of exocrine pancreatic insufficiency by treatment with pancreatic extracts. Primary lactase deficiency exists in various forms. Besides congenital lactase deficiency, the late onset or adult type of lactase deficiency has been observed. The latter occurs in many different ethnic groups around the world. Here, using gel electrophoresis and immunoelectrophoresis, the lack of enzyme activity could be shown to be a primary defect in enzyme protein synthesis. In man and in the rat, two different lactases have been identified. In contrast to adult lactase, fetal lactase contains sialic acid at the end of carbohydrate side chains.(ABSTRACT TRUNCATED AT 250 WORDS)
Lactose digestion from yogurt: mechanism and relevance.
Savaiano, Dennis A
2014-05-01
Yogurt is traditionally consumed throughout the world among populations who are seemingly unable to digest lactose. This review provides a historical overview of the studies that show lactose digestion and tolerance from yogurt by lactose-intolerant people. The lactose in yogurt is digested more efficiently than other dairy sources of lactose because the bacteria inherent in yogurt assist with its digestion. The bacterial lactase survives the acidic conditions of the stomach, apparently being physically protected within the bacterial cells and facilitated by the buffering capacity of yogurt. The increasing pH as the yogurt enters the small intestine and a slower gastrointestinal transit time allow the bacterial lactase to be active, digesting lactose from yogurt sufficiently to prevent symptoms in lactose-intolerant people. There is little difference in the lactase capability of different commercial yogurts, because they apparently contain Lactobacillus bulgaricus and Streptococcus thermophilus in sufficient quantities (10(8) bacteria/mL). However, Lactobacillus acidophilus appears to require cell membrane disruption to physically release the lactase. Compared with unflavored yogurts, flavored yogurts appear to exhibit somewhat reduced lactase activity but are still well tolerated.
van de Heijning, Bert J. M.; Kegler, Diane; Schipper, Lidewij; Voogd, Eline; Oosting, Annemarie; van der Beek, Eline M.
2015-01-01
Neonatal rats have a high intestinal lactase activity, which declines around weaning. Yet, the effects of lactose-containing products are often studied in adult animals. This report is on the residual, post-weaning lactase activity and on the short- and long-term effects of lactose exposure in adult rats. Acutely, the postprandial plasma response to increasing doses of lactose was studied, and chronically, the effects of a 30% lactose diet fed from postnatal (PN) Day 15 onwards were evaluated. Intestinal lactase activity, as assessed both in vivo and in vitro, was compared between both test methods and diet groups (lactose vs. control). A 50%–75% decreased digestive capability towards lactose was observed from weaning into adulthood. Instillation of lactose in adult rats showed disproportionally low increases in plasma glucose levels and did not elicit an insulin response. However, gavages comprising maltodextrin gave rise to significant plasma glucose and insulin responses, indicative of a bias of the adult GI tract to digest glucose polymers. Despite the residual intestinal lactase activity shown, a 30% lactose diet was poorly digested by adult rats: the lactose diet rendered the animals less heavy and virtually devoid of body fat, whereas their cecum tripled in size, suggesting an increased bacterial fermentation. The observed acute and chronic effects of lactose exposure in adult rats cannot be explained by the residual intestinal lactase activity assessed. PMID:26184291
21 CFR 184.1387 - Lactase enzyme preparation from Candida pseudotropicalis.
Code of Federal Regulations, 2012 CFR
2012-04-01
..., nontoxicogenic yeast C. pseudotropicalis. It contains the enzyme lactase (β-D-galactoside galactohydrolase, EC 3.2.1.23), which converts lactose to glucose and galactose. It is prepared from yeast that has been...
21 CFR 184.1387 - Lactase enzyme preparation from Candida pseudotropicalis.
Code of Federal Regulations, 2013 CFR
2013-04-01
..., nontoxicogenic yeast C. pseudotropicalis. It contains the enzyme lactase (β-D-galactoside galactohydrolase, EC 3.2.1.23), which converts lactose to glucose and galactose. It is prepared from yeast that has been...
Venkateswarulu, T C; Prabhakar, K Vidya; Kumar, R Bharath; Krupanidhi, S
2017-07-01
Modeling and optimization were performed to enhance production of lactase through submerged fermentation by Bacillus subtilis VUVD001 using artificial neural networks (ANN) and response surface methodology (RSM). The effect of process parameters namely temperature (°C), pH, and incubation time (h) and their combinational interactions on production was studied in shake flask culture by Box-Behnken design. The model was validated by conducting an experiment at optimized process variables which gave the maximum lactase activity of 91.32 U/ml. Compared to traditional activity, 3.48-folds improved production was obtained after RSM optimization. This study clearly shows that both RSM and ANN models provided desired predictions. However, compared with RSM (R 2 = 0.9496), the ANN model (R 2 = 0.99456) gave a better prediction for the production of lactase.
Fine-scale human genetic structure in Western France.
Karakachoff, Matilde; Duforet-Frebourg, Nicolas; Simonet, Floriane; Le Scouarnec, Solena; Pellen, Nadine; Lecointe, Simon; Charpentier, Eric; Gros, Françoise; Cauchi, Stéphane; Froguel, Philippe; Copin, Nane; Le Tourneau, Thierry; Probst, Vincent; Le Marec, Hervé; Molinaro, Sabrina; Balkau, Beverley; Redon, Richard; Schott, Jean-Jacques; Blum, Michael Gb; Dina, Christian
2015-06-01
The difficulties arising from association analysis with rare variants underline the importance of suitable reference population cohorts, which integrate detailed spatial information. We analyzed a sample of 1684 individuals from Western France, who were genotyped at genome-wide level, from two cohorts D.E.S.I.R and CavsGen. We found that fine-scale population structure occurs at the scale of Western France, with distinct admixture proportions for individuals originating from the Brittany Region and the Vendée Department. Genetic differentiation increases with distance at a high rate in these two parts of Northwestern France and linkage disequilibrium is higher in Brittany suggesting a lower effective population size. When looking for genomic regions informative about Breton origin, we found two prominent associated regions that include the lactase region and the HLA complex. For both the lactase and the HLA regions, there is a low differentiation between Bretons and Irish, and this is also found at the genome-wide level. At a more refined scale, and within the Pays de la Loire Region, we also found evidence of fine-scale population structure, although principal component analysis showed that individuals from different departments cannot be confidently discriminated. Because of the evidence for fine-scale genetic structure in Western France, we anticipate that rare and geographically localized variants will be identified in future full-sequence analyses.
Macholdt, Enrico; Slatkin, Montgomery; Pakendorf, Brigitte; Stoneking, Mark
2015-04-01
Lactase persistence (LP), the ability to digest lactose into adulthood, is strongly associated with the cultural traits of pastoralism and milk-drinking among human populations, and several different genetic variants are known that confer LP. Recent studies of LP variants in Southern African populations, with a focus on Khoisan-speaking groups, found high frequencies of an LP variant (the C-14010 allele) that also occurs in Eastern Africa, and concluded that the C-14010 allele was brought to Southern Africa via a migration of pastoralists from Eastern Africa. However, this conclusion was based on indirect evidence; to date no study has jointly analyzed data on the C-14010 allele from both Southern African Khoisan-speaking groups and Eastern Africa. Here, we combine and analyze published data on the C-14010 allele in Southern and Eastern African populations, consisting of haplotypes with the C-14010 allele and four closely-linked short tandem repeat loci. Our results provide direct evidence for the previously-hypothesized Eastern African origin of the C-14010 allele in Southern African Khoisan-speaking groups. In addition, we find evidence for a separate introduction of the C-14010 allele into the Bantu-speaking Xhosa. The estimated selection intensity on the C-14010 allele in Eastern Africa is lower than that in Southern Africa, which suggests that in Eastern Africa the dietary changes conferring the fitness advantage associated with LP occurred some time after the origin of the C-14010 allele. Conversely, in Southern Africa the fitness advantage was present when the allele was introduced, as would be expected if pastoralism was introduced concomitantly. © 2014 Wiley Periodicals, Inc.
Yang, Q; Lin, S L; Au Yeung, S L; Kwok, M K; Xu, L; Leung, G M; Schooling, C M
2017-08-01
Milk provides protein and micronutrients, and is recommended by some dietary guidelines, particularly for bone health. Meta-analysis of small randomized controlled trials suggests that milk may increase bone mineral density, but they are very heterogeneous. No randomized controlled trial has assessed the effects of milk on major chronic diseases. Previous Mendelian randomization studies of milk did not consider bone health, found no effects on ischemic heart disease (IHD) or type 2 diabetes (T2D) but higher body mass index. Using larger genetic studies, we estimated the effects of milk on osteoporosis, IHD, T2D, adiposity, lipids and glycemic traits. Instrumental variable analysis based on a genetic variant endowing lactase persistence (rs4988235 (MCM6)) was used to obtain estimates for osteoporosis (GEFOS), IHD (CARDIoGRAMplusC4D), T2D (DIAGRAM), adiposity (GIANT), lipids (GLGC) and glycaemic traits (MAGIC). Eye color was a negative control for IHD, as it mirrors the distribution of lactase persistence and IHD in Western Europe. Genetically predicted adult milk consumption was not clearly associated with bone mineral density, IHD (odds ratio (OR): 1.03 per s.d., 95% confidence interval (CI): 0.95-1.12) and or T2D (OR: 0.92, 95% CI: 0.83-1.02) but was associated with higher log-transformed fasting insulin (0.05, 95% CI: 0.02-0.07) and body mass index (0.06, 95% CI: 0.03-0.09). Genetically predicted eye color was not associated with IHD. The lack of association of genetically predicted milk consumption with bone health, IHD or T2D suggests few beneficial effects but is more consistent with milk promoting adiposity.
Alginate Beads Containing Lactase: Stability and Microstructure.
Traffano-Schiffo, Maria Victoria; Aguirre Calvo, Tatiana R; Castro-Giraldez, Marta; Fito, Pedro J; Santagapita, Patricio R
2017-06-12
β-Galactosidase (lactase) is a widely used enzyme in the food industry; however, it has low stability against thermal and mechanical treatments. Due to this, the purpose of the present research was to analyze the encapsulation of lactase in alginate-Ca(II) beads in order to maintain its enzymatic activity toward freezing, freezing/thawing, and storage. Also, the effect of the addition of trehalose, and arabic and guar gums and their influence on the microstructure as well as on thermal properties and molecular mobility were studied. Lactase was successfully encapsulated in alginate-Ca(II) beads, and the inclusion of trehalose was critical for activity preservation toward treatments, being improved in guar gum-containing systems. The gums increased the T m ' values, which represents a valuable technological improvement. Finally, the presence of secondary excipients affected the microstructure, showing rods with smaller outer diameter and with lower compactness than alginate-Ca(II) beads. Also, bead composition greatly affects the size, shape, and relaxation times.
Ontogeny of intestinal safety factors: lactase capacities and lactose loads.
O'Connor, T P; Diamond, J
1999-03-01
We measured intestinal safety factors (ratio of a physiological capacity to the load on it) for lactose digestion in developing rat pups. Specifically, we assessed the quantitative relationships between lactose load and the series capacities of lactase and the Na+-glucose cotransporter (SGLT-1). Both capacities increased significantly with age in suckling pups as a result of increasing intestinal mass and maintenance of mass-specific activities. The youngest pups examined (5 days) had surprisingly high safety factors of 8-13 for both lactase and SGLT-1, possibly because milk contains lactase substrates other than lactose; it also, however, suggests that their intestinal capacities were being prepared to meet future demands rather than just current ones. By day 10 (and also at day 15), increased lactose loads resulted in lower safety factors of 4-6, values more typical of adult intestines. The safety factor of SGLT-1 in day 30 (weanling) and day 100 (adult) rats was only approximately 1.0. This was initially unexpected, because most adult intestines maintain a modest reserve capacity beyond nutrient load values, but postweaning rats appear to use hindgut fermentation, assessed by gut morphology and hydrogen production assays, as a built-in reserve capacity. The series capacities of lactase and SGLT-1 varied in concert with each other over ontogeny and as lactose load was manipulated by experimental variation in litter size.
A Guided-Inquiry pH Laboratory Exercise for Introductory Biological Science Laboratories
ERIC Educational Resources Information Center
Snodgrass, Meagan A.; Lux, Nicholas; Metz, Anneke M.
2011-01-01
There is a continuing need for engaging inquiry-based laboratory experiences for advanced high school and undergraduate biology courses. The authors describe a guided-inquiry exercise investigating the pH-dependence of lactase enzyme that uses an inexpensive, wide-range buffering system, lactase dietary supplement, over-the-counter glucose test…
21 CFR 184.1388 - Lactase enzyme preparation from Kluyveromyces lactis.
Code of Federal Regulations, 2011 CFR
2011-04-01
...-galactoside galactohydrase (CAS Reg. No. CBS 683), which converts lactose to glucose and galactose. It is... in § 170.3(o)(9) of this chapter to convert lactose to glucose and galactose. (2) The ingredient is... practice is to use this ingredient in milk to produce lactase-treated milk, which contains less lactose...
21 CFR 184.1388 - Lactase enzyme preparation from Kluyveromyces lactis.
Code of Federal Regulations, 2010 CFR
2010-04-01
...-galactoside galactohydrase (CAS Reg. No. CBS 683), which converts lactose to glucose and galactose. It is... in § 170.3(o)(9) of this chapter to convert lactose to glucose and galactose. (2) The ingredient is... practice is to use this ingredient in milk to produce lactase-treated milk, which contains less lactose...
Gums induced microstructure stability in Ca(II)-alginate beads containing lactase analyzed by SAXS.
Traffano-Schiffo, Maria Victoria; Castro-Giraldez, Marta; Fito, Pedro J; Perullini, Mercedes; Santagapita, Patricio R
2018-01-01
Previous works show that the addition of trehalose and gums in β-galactosidase (lactase) Ca(II)-alginate encapsulation systems improved its intrinsic stability against freezing and dehydration processes in the pristine state. However, there is no available information on the evolution in microstructure due to the constraints imposed by the operational conditions. The aim of this research is to study the time course of microstructural changes of Ca(II)-alginate matrices driven by the presence of trehalose, arabic and guar gums as excipients and to discuss how these changes influence the diffusional transport (assessed by LF-NMR) and the enzymatic activity of the encapsulated lactase. The structural modifications at different scales were assessed by SAXS. The incorporation of gums as second excipients induces a significant stabilization in the microstructure not only at the rod scale, but also in the characteristic size and density of alginate dimers (basic units of construction of rods) and the degree of interconnection of rods at a larger scale, improving the performance in terms of lactase activity. Copyright © 2017 Elsevier Ltd. All rights reserved.
Diagnosis of genetic predisposition for lactose intolerance by high resolution melting analysis.
Delacour, Hervé; Leduc, Amandine; Louçano-Perdriat, Andréa; Plantamura, Julie; Ceppa, Franck
2017-02-01
Lactose, the principle sugar in milk, is a disaccharide hydrolyzed by intestinal lactase into glucose and galactose, which are absorbed directly by diffusion in the intestine. The decline of lactase expression (or hypolactasia) in intestinal microvilli after weaning is a normal phenomenon in mammals known as lactase deficiency. It is observed in nearly 75% of the world population and is an inherited autosomal recessive trait with incomplete penetrance. It is caused by SNPs in a regulatory element for lactase gene. In Indo-European, lactase deficiency is associated with rs4982235 SNP (or -13910C>T). The aim of this study is to describe a method based on high resolution melting for rapidly detecting genetic predisposition to lactose intolerance. Analytical performance of the assay was assessed by evaluating within and betwwen-run precision and by comparing the results (n = 50 patients) obtained with the HRM assay to those obtained with the gold standard (Sanger sequencing of the region of interest). In silico prediction of HRM curves was performed to evaluate the potential impact of the other SNPs described within the PCR product on the HRM analytical performances. The assay has good performance (CV <0.2% during the between-run study). A perfect agreement with the gold standard method was observed. The presence of other polymorphisms within the amplified sequence is detected, the misclassification risk is low. This assay can be used for rapidly diagnosing genetic predisposition to lactose intolerance.
ERIC Educational Resources Information Center
Kushak, Rafail I.; Lauwers, Gregory Y.; Winter, Harland S.; Buie, Timothy M.
2011-01-01
Intestinal disaccharidase activities were measured in 199 individuals with autism to determine the frequency of enzyme deficiency. All patients had duodenal biopsies that were evaluated morphologically and assayed for lactase, sucrase, and maltase activity. Frequency of lactase deficiency was 58% in autistic children less than or equal to 5 years…
Measurement of Enzyme Kinetics by Use of a Blood Glucometer: Hydrolysis of Sucrose and Lactose
ERIC Educational Resources Information Center
Heinzerling, Peter; Schrader, Frank; Schanze, Sascha
2012-01-01
An alternative analytical method for measuring the kinetic parameters of the enzymes invertase and lactase is described. Invertase hydrolyzes sucrose to glucose and fructose and lactase hydrolyzes lactose to glucose and galactose. In most enzyme kinetics studies, photometric methods or test strips are used to quantify the derivates of the…
Zhang, Xiao-Hong; Cai, Qing-Xian; Hong, Chun-Xia; Lin, Chao-Shuang; Zhao, Zhi-Xin
2013-07-01
The geographic distribution, demographics, epidemiology, host factors, and clinical characteristics of persistent HCV-6 infection in China need further characterization. This multicenter study enrolled 63 patients with persistent HCV-6 infection and 63 patients with persistent HCV-1 infection as controls. Blood biochemistry, quantitation of HCV RNA levels, and identification of host IL-28B genotypes (rs12979860, rs8099917, and rs12980275) and ITPA genotype (rs1127354) were performed to estimate potential variability in host factors that may affect response to treatment. The mean HCV-6 RNA level (3.8E6 IU/ml) was significantly higher than that in patients infected with HCV-1 (1.7E6 IU/ml; P < 0.001). Patients persistently infected with HCV-6 had a high prevalence of IL-28B rs12979860 CC genotype (92.1%), rs8099917 TT genotype (93.7%), and rs12980275 AA genotype (90.5%). Their prevalence in patients infected with HCV-1 was only modestly lower (82.5%, 84.1%, and 82.5%, respectively; P > 0.05). The inosine triphosphate pyrophosphatase (ITPA) SNP rs1127354 CC genotype was present in 66.7% of patients infected with HCV-6, comparable to that of patients infected with HCV-1 (65.1%; P > 0.05). There were no differences in the liver function, proportion of hepatic cirrhosis patients or patients with increased serum glucose between these two groups. Persistent HCV-6 infection in Chinese Han is found mainly in the southern China. Chinese Han with chronic HCV-1 or HCV-6 infection have IL-28B genotypes, suggesting responsiveness to interferon-based pharmacotherapy. Most patients (67%) possess the ITPA genotype associated with susceptibility to ribavirin-induced hemolysis. The routes of transmission for HCV-6 genotype were more diversified than HCV-1 genotype. The outbreak of HCV-6 infection through blood transfusion progressed faster than HCV-1. Copyright © 2013 Wiley Periodicals, Inc.
Four novel mutations in the lactase gene (LCT) underlying congenital lactase deficiency (CLD).
Torniainen, Suvi; Freddara, Roberta; Routi, Taina; Gijsbers, Carolien; Catassi, Carlo; Höglund, Pia; Savilahti, Erkki; Järvelä, Irma
2009-01-22
Congenital lactase deficiency (CLD) is a severe gastrointestinal disorder of newborns. The diagnosis is challenging and based on clinical symptoms and low lactase activity in intestinal biopsy specimens. The disease is enriched in Finland but is also present in other parts of the world. Mutations encoding the lactase (LCT) gene have recently been shown to underlie CLD. The purpose of this study was to identify new mutations underlying CLD in patients with different ethnic origins, and to increase awareness of this disease so that the patients could be sought out and treated correctly. Disaccharidase activities in intestinal biopsy specimens were assayed and the coding region of LCT was sequenced from five patients from Europe with clinical features compatible with CLD. In the analysis and prediction of mutations the following programs: ClustalW, Blosum62, PolyPhen, SIFT and Panther PSEC were used. Four novel mutations in the LCT gene were identified. A single nucleotide substitution leading to an amino acid change S688P in exon 7 and E1612X in exon 12 were present in a patient of Italian origin. Five base deletion V565fsX567 leading to a stop codon in exon 6 was found in one and a substitution R1587H in exon 12 from another Finnish patient. Both Finnish patients were heterozygous for the Finnish founder mutation Y1390X. The previously reported mutation G1363S was found in a homozygous state in two siblings of Turkish origin. This is the first report of CLD mutations in patients living outside Finland. It seems that disease is more common than previously thought. All mutations in the LCT gene lead to a similar phenotype despite the location and/or type of mutation.
Short communication: Effect of active food packaging materials on fluid milk quality and shelf life.
Wong, Dana E; Goddard, Julie M
2014-01-01
Active packaging, in which active agents are embedded into or on the surface of food packaging materials, can enhance the nutritive value, economics, and stability of food, as well as enable in-package processing. In one embodiment of active food packaging, lactase was covalently immobilized onto packaging films for in-package lactose hydrolysis. In prior work, lactase was covalently bound to low-density polyethylene using polyethyleneimine and glutaraldehyde cross-linkers to form the packaging film. Because of the potential contaminants of proteases, lipases, and spoilage organisms in typical enzyme preparations, the goal of the current work was to determine the effect of immobilized-lactase active packaging technology on unanticipated side effects, such as shortened shelf-life and reduced product quality. Results suggested no evidence of lipase or protease activity on the active packaging films, indicating that such active packaging films could enable in-package lactose hydrolysis without adversely affecting product quality in terms of dairy protein or lipid stability. Storage stability studies indicated that lactase did not migrate from the film over a 49-d period, and that dry storage resulted in 13.41% retained activity, whereas wet storage conditions enabled retention of 62.52% activity. Results of a standard plate count indicated that the film modification reagents introduced minor microbial contamination; however, the microbial population remained under the 20,000 cfu/mL limit through the manufacturer's suggested 14-d storage period for all film samples. This suggests that commercially produced immobilized lactase active packaging should use purified cross-linkers and enzymes. Characterization of unanticipated effects of active packaging on food quality reported here is important in demonstrating the commercial potential of such technologies. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Hajare, Sunil Tulshiram; Bekele, Genene
2017-01-01
Clinically proven Lactobacillus acidophilus strain LBKV-3 intended as probiotic for humans was used to test its effect on fecal residual lactase activity in undernourished children below 10 years of age. The children were selected from malnutrition-declared area of Maharashtra (India). One of the major causes of malnutrition is lactose intolerance which leads to diarrhea. The basic consideration in selecting the probiotic strain of L. acidophilus (LBKV-3) in this investigation was the fact that the organism is isolated from human vaginal surface swab and it was found extensively studied for probiotic characteristic. LBKB 3 is tested by several workers as probiotic for hypocholesterolemic activity, implantation ability, therapeutic effects on gastrointestinal (GI) and related ailments. The results of present investigation have shown that the fecal residual lactase activity significantly increased than its initial value (which was almost zero). It appeared that the fecal residual β-galactosidase activity is an indication of positive implementation abilities of the cultures under investigation. These trends were compared with the control and blank group of children receiving Dahi and buffalo milk (BM). It was observed that both these products failed to exert any significant impact on increase in residual lactase activity.
Ito, Kiyoaki; Yotsuyanagi, Hiroshi; Yatsuhashi, Hiroshi; Karino, Yoshiyasu; Takikawa, Yasuhiro; Saito, Takafumi; Arase, Yasuji; Imazeki, Fumio; Kurosaki, Masayuki; Umemura, Takeji; Ichida, Takafumi; Toyoda, Hidenori; Yoneda, Masashi; Mita, Eiji; Yamamoto, Kazuhide; Michitaka, Kojiro; Maeshiro, Tatsuji; Tanuma, Junko; Tanaka, Yasuhito; Sugiyama, Masaya; Murata, Kazumoto; Masaki, Naohiko; Mizokami, Masashi
2014-01-01
The proportion of patients who progress to chronicity following acute hepatitis B (AHB) varies widely worldwide. Moreover, the association between viral persistence after AHB and hepatitis B virus (HBV) genotypes in adults remains unclear. A nationwide multicenter study was conducted throughout Japan to evaluate the influence of clinical and virological factors on chronic outcomes in patients with AHB. For comparing factors between AHB patients with viral persistence and those with self-limited infection, 212 AHB patients without human immunodeficiency virus (HIV) coinfection were observed in 38 liver centers until serum hepatitis B surface antigen (HBsAg) disappeared or a minimum of 6 months in cases where HBsAg persisted. The time to disappearance of HBsAg was significantly longer for genotype A patients than that of patients infected with non-A genotypes. When chronicity was defined as the persistence of HBsAg positivity for more than 6 or 12 months, the rate of progression to chronicity was higher in patients with genotype A, although many cases caused by genotype A were prolonged cases of AHB, rather than chronic infection. Multivariate logistic regression analysis revealed only genotype A was independently associated with viral persistence following AHB. A higher peak level of HBV DNA and a lower peak of alanine aminotransferase (ALT) levels were characteristics of AHB caused by genotype A. Treatment with nucleotide analogs (NAs) did not prevent progression to chronic infection following AHB overall. Subanalysis suggested early NA initiation may enhance the viral clearance. Genotype A was an independent risk factor for progression to chronic infection following AHB. Our data will be useful in elucidating the association between viral persistence after AHB, host genetic factors, and treatment with NAs in future studies. © 2013 by the American Association for the Study of Liver Diseases.
Lactose intolerance: from diagnosis to correct management.
Di Rienzo, T; D'Angelo, G; D'Aversa, F; Campanale, M C; Cesario, V; Montalto, M; Gasbarrini, A; Ojetti, V
2013-01-01
This review discusses one of the most relevant problems in gastrointestinal clinical practice: lactose intolerance. The role of lactase-persistence alleles the diagnosis of lactose malabsorption the development of lactose intolerance symptoms and its management. Most people are born with the ability to digest lactose, the major carbohydrate in milk and the main source of nutrition until weaning. Approximately, 75% of the world's population loses this ability at some point, while others can digest lactose into adulthood. Symptoms of lactose intolerance include abdominal pain, bloating, flatulence and diarrhea with a considerable intraindividual and interindividual variability in the severity. Diagnosis is most commonly performed by the non invasive lactose hydrogen breath test. Management of lactose intolerance consists of two possible clinical choice not mutually exclusive: alimentary restriction and drug therapy.
Paaso, Ulla; Keski-Saari, Sarita; Keinänen, Markku; Karvinen, Heini; Silfver, Tarja; Rousi, Matti; Mikola, Juha
2017-01-01
Abundant secondary metabolites, such as condensed tannins, and their interpopulation genotypic variation can remain through plant leaf senescence and affect litter decomposition. Whether the intrapopulation genotypic variation of a more diverse assortment of secondary metabolites equally persists through leaf senescence and litter decomposition is not well understood. We analyzed concentrations of intracellular phenolics, epicuticular flavonoid aglycones, epicuticular triterpenoids, condensed tannins, and lignin in green leaves, senescent leaves and partly decomposed litter of silver birch, Betula pendula. Broad-sense heritability (H2) and coefficient of genotypic variation (CVG) were estimated for metabolites in senescent leaves and litter using 19 genotypes selected from a B. pendula population in southern Finland. We found that most of the secondary metabolites remained through senescence and decomposition and that their persistence was related to their chemical properties. Intrapopulation H2 and CVG for intracellular phenolics, epicuticular flavonoid aglycones and condensed tannins were high and remarkably, increased from senescent leaves to decomposed litter. The rank of genotypes in metabolite concentrations was persistent through litter decomposition. Lignin was an exception, however, with a diminishing genotypic variation during decomposition, and the concentrations of lignin and condensed tannins had a negative genotypic correlation in the senescent leaves. Our results show that secondary metabolites and their intrapopulation genotypic variation can for the most part remain through leaf senescence and early decomposition, which is a prerequisite for initial litter quality to predict variation in litter decomposition rates. Persistent genotypic variation also opens an avenue for selection to impact litter decomposition in B. pendula populations through acting on their green foliage secondary chemistry. The negative genotypic correlations and diminishing heritability of lignin concentrations may, however, counteract this process. PMID:28694813
Paaso, Ulla; Keski-Saari, Sarita; Keinänen, Markku; Karvinen, Heini; Silfver, Tarja; Rousi, Matti; Mikola, Juha
2017-01-01
Abundant secondary metabolites, such as condensed tannins, and their interpopulation genotypic variation can remain through plant leaf senescence and affect litter decomposition. Whether the intrapopulation genotypic variation of a more diverse assortment of secondary metabolites equally persists through leaf senescence and litter decomposition is not well understood. We analyzed concentrations of intracellular phenolics, epicuticular flavonoid aglycones, epicuticular triterpenoids, condensed tannins, and lignin in green leaves, senescent leaves and partly decomposed litter of silver birch, Betula pendula . Broad-sense heritability ( H 2 ) and coefficient of genotypic variation ( CV G ) were estimated for metabolites in senescent leaves and litter using 19 genotypes selected from a B. pendula population in southern Finland. We found that most of the secondary metabolites remained through senescence and decomposition and that their persistence was related to their chemical properties. Intrapopulation H 2 and CV G for intracellular phenolics, epicuticular flavonoid aglycones and condensed tannins were high and remarkably, increased from senescent leaves to decomposed litter. The rank of genotypes in metabolite concentrations was persistent through litter decomposition. Lignin was an exception, however, with a diminishing genotypic variation during decomposition, and the concentrations of lignin and condensed tannins had a negative genotypic correlation in the senescent leaves. Our results show that secondary metabolites and their intrapopulation genotypic variation can for the most part remain through leaf senescence and early decomposition, which is a prerequisite for initial litter quality to predict variation in litter decomposition rates. Persistent genotypic variation also opens an avenue for selection to impact litter decomposition in B. pendula populations through acting on their green foliage secondary chemistry. The negative genotypic correlations and diminishing heritability of lignin concentrations may, however, counteract this process.
Rosado, Jorge L
2016-09-01
The most common problem limiting milk consumption worldwide is lactose intolerance (LI), which is defined as the experience of gastrointestinal symptoms due to the intake of lactose-containing food. When symptoms ensue the intake of milk, the condition is referred as milk intolerance, and it may or may not be due to LI. The most common cause of LI is primary lactase deficiency which occurs in 30% of Mexican adults when one glass of milk is consumed (12-18 g of lactose). LI occurs in less than 15% of adults after the intake of this dose of lactose. Another cause of lactose intolerance is due to secondary lactase deficiency, which occurs because lactase is reduced due to diseases that affect the intestinal mucosa. Lactose intolerance can be eliminated or significantly reduced by elimination or reduction of the intake of milk and milk containing products. Recent studies demonstrate that when β-casein-A1 contained in milk is hydrolyzed it produces β-casomorphine-7 which is an opioid associated with milk intolerance.
Disaccharidase Deficiencies in Children With Chronic Abdominal Pain.
El-Chammas, Khalil; Williams, Sara E; Miranda, Adrian
2017-03-01
Carbohydrate intolerance or malabsorption has been suggested as a cause of chronic abdominal pain (CAP) in a subset of patients. We aimed to evaluate disaccharidase deficiencies in children with functional CAP and to correlate deficiencies with clinical features. Patients presenting to the gastroenterology clinic at Children's Hospital of Wisconsin with abdominal pain prospectively completed a detailed demographic, history, and symptom questionnaire. The CAP cohort included those with at least 1 month of symptoms. Data on disaccharidase activity and histology of endoscopic biopsies were collected retrospectively. Only patients with normal histology were included in the study. The association between groups with low disaccharidases and clinical features was examined. A total of 203 pediatric patients with CAP were included. The mean (SD) age was 11.5 (3.1) years, and 32.5% were male. The percentages of abnormally low disaccharidase levels using the standard laboratory cutoffs were lactase, 37%; sucrase, 21%; glucoamylase, 25%; and palatinase, 8%. Thirty-nine percent of the patients with low lactase also had low sucrase, and 67% of the patients with low sucrase had low lactase. There was no significant difference in the activities of any of the disaccharidases or sucrase/lactase ratio in relation to age. Also, no association was found between stool consistency, stool frequency, or location of pain and low disaccharidase activity. A large proportion of patients with CAP have deficiencies in disaccharidases. Bowel frequency, vomiting, or location of pain was no different between groups, suggesting that these clinical features cannot be used to predict disaccharidase deficiencies.
Cornall, Alyssa M; Roberts, Jennifer M; Molano, Monica; Machalek, Dorothy A; Phillips, Samuel; Hillman, Richard J; Grulich, Andrew E; Jin, Fengyi; Poynten, I Mary; Templeton, David J; Garland, Suzanne M; Tabrizi, Sepehr N
2015-01-01
Introduction Anal squamous cell carcinoma is preceded by persistent infection with high-risk human papillomavirus (HPV) and the cancer precursor, high-grade squamous intraepithelial lesion (HSIL). Detection of specific HPV genotypes and HPV-related biomarkers may be an option for primary anal screening. However, more data on the natural history of HPV-related anal lesions are required. The outcomes from this study will enhance our understanding of the clinical and biological behaviour of HPV-related anal lesions and inform the development of future HPV genotype and/or biomarker screening tests. Methods and analysis HIV-negative and HIV-positive men who have sex with men, aged 35 years and over, recruited from community-based settings in Sydney, Australia, attend 6 clinic visits over 3 years. At the first 5 visits, participants undergo a digital anorectal examination, an anal swab for HPV genotyping and anal cytology, and high-resolution anoscopy with directed biopsy of any visible abnormalities that are suggestive of any abnormality suspicious of SIL. Tissue sections from participants diagnosed with histologically confirmed HSIL at the baseline clinic visit will undergo laser capture microdissection, HPV detection and genotyping, and quantitation of CpG methylation in baseline and follow-up biopsies. Histological and cytological findings in combination with HPV genotyping data will be used to identify persistent HSIL. HSIL will be stratified as non-persistent and persistent based on their status at 12 months. The performance of HPV genotype and methylation status in predicting disease persistence at 12 months will be assessed, along with associations with HIV status and other covariates such as age. Ethics and dissemination The St Vincent's Hospital Ethics Committee granted ethics approval for the study. Written informed consent is obtained from all individuals before any study-specific procedures are performed. Findings from this study will be disseminated to participants and the community through study newsletters, and through peer-reviewed publications and international conferences. PMID:26310402
Rivera-Sagredo, A; Fernández-Mayoralas, A; Jiménez-Barbero, J; Martín-Lomas, M; Villanueva, D; Aragón, J J
1992-04-10
4-O-beta-D-Galactopyranosyl-D-xylose (2) was prepared from benzyl 2,3-O-isopropylidene-beta-D-xylopyranoside by glycosylation with 2,3,4,6-tetra-O-benzoyl-alpha-D-galactopyranosyl bromide and subsequent deprotection. Compound 2 was hydrolyzed in vitro by intestinal lactase; the Vmax was 25% of that with lactose and the Km was 370mM (cf. 27mM for lactose). Oral administration of 2 suckling rats led to urinary excretion of D-xylose which could be estimated colorimetrically.
Avetisian, L R; Voronina, O L; Chernukha, M Iu; Kunda, M S; Gabrielian, N I; Lunin, V G; Shaginian, I A
2012-01-01
Study genetic diversity of P. aeruginosa strains persisting in patients of Federal Scientific Center of Transplantology and Artificial Organs, and main factors facilitating persistence of strains in the hospital. 136 P. aeruginosa strains isolated from patients of the center for 3 years 6 months were genotyped by RAPD-PCR and MLST methods and studied for antibiotics resistance and presence of integrons. Genetic diversity of strains persisting in hospital was established. Strains of main genotypes ST235, ST446, ST598 were isolated from patients of various surgical departments. Patients were shown to be colonized by these strains during stay in reanimation and intensive therapy department (RITD) of the hospital. Strains of dominant genotype 235 were isolated from 47% of examined patients during more than 3 years. Only genotype 235 strains contained integron with cassettes of antibiotics resistance genes blaGES5 and aadA6 in the genome. The data obtained show that over the period of observation in the center 1 clone of P. aeruginosa that belonged to genotype 235 dominated. This clone was endemic for this hospital and in the process of prolonged persistence became more resistant to antibiotics. Colonization of patients with these strains occurs in RITD. This confirms the necessity of constant monitoring of hospital microflora for advance detection of potentially dangerous epidemic hospital strains able to cause hospital infections.
Teramura, H; Sota, K; Iwasaki, M; Ogihara, H
2017-07-01
Sanita-kun™ CC (coliform count) and EC (Escherichia coli/coliform count), sheet quantitative culture systems which can avoid chromogenic interference by lactase in food, were evaluated in comparison with conventional methods for these bacteria. Based on the results of inclusivity and exclusivity studies using 77 micro-organisms, sensitivity and specificity of both Sanita-kun™ met the criteria for ISO 16140. Both media were compared with deoxycholate agar, violet red bile agar, Merck Chromocult™ coliform agar (CCA), 3M Petrifilm™ CC and EC (PEC) and 3-tube MPN, as reference methods, in 100 naturally contaminated food samples. The correlation coefficients of both Sanita-kun™ for coliform detection were more than 0·95 for all comparisons. For E. coli detection, Sanita-kun™ EC was compared with CCA, PEC and MPN in 100 artificially contaminated food samples. The correlation coefficients for E. coli detection of Sanita-kun™ EC were more than 0·95 for all comparisons. There were no significant differences in all comparisons when conducting a one-way analysis of variance (anova). Both Sanita-kun™ significantly inhibited colour interference by lactase when inhibition of enzymatic staining was assessed using 40 natural cheese samples spiked with coliform. Our results demonstrated Sanita-kun™ CC and EC are suitable alternatives for the enumeration of coliforms and E. coli/coliforms, respectively, in a variety of foods, and specifically in fermented foods. Current chromogenic media for coliforms and Escherichia coli/coliforms have enzymatic coloration due to breaking down of chromogenic substrates by food lactase. The novel sheet culture media which have film layer to avoid coloration by food lactase have been developed for enumeration of coliforms and E. coli/coliforms respectively. In this study, we demonstrated these media had comparable performance with reference methods and less interference by food lactase. These media have a possibility not only to be useful alternatives but also to contribute for accurate enumeration of these bacteria in a variety of foods, and specifically in fermented foods. © 2017 The Society for Applied Microbiology.
Lactose digestion by human jejunal biopsies: the relationship between hydrolysis and absorption.
Dawson, D J; Lobley, R W; Burrows, P C; Miller, V; Holmes, R
1986-01-01
The relationship between lactose hydrolysis and absorption of released glucose was investigated by determining the kinetics of lactose digestion by jejunal biopsies incubated in vitro. Lactase activity in intact biopsies correlated with conventional assay of tissue homogenates (r = 0.85, p less than 0.001), and glucose uptake from 28 mM lactose was directly proportional to lactase activity (r = 0.95, p less than 0.001) in 21 subjects with normal lactase levels, six with hypolactasia (primary or secondary to coeliac disease) and two with lactose intolerance but normal lactase activity. Kinetic analysis at 0.56-56 mM lactose in five normal subjects showed saturable kinetics for hydrolysis (app Km = 33.9 +/- 2.2 mM; app Vmax = 26.5 +/- 1.1 nmol/min/mg dry weight) but glucose uptake could be fitted to a model either of saturable uptake (app Kt = 47.2 +/- 0.3 mM; app Jmax = 14.1 +/- 0.2 nmol/min/mg) or saturable uptake plus a linear component (app Kt = 21.3 +/- 1.15; app Jmax = 4.59 +/- 0.12; app Kd = 0.093 +/- 0.010 nmol/min/mg/mM). The proportion of glucose taken into the tissue did not significantly exceed 50% of the total released at any lactose concentration suggesting the lack of an efficient capture mechanism for the released glucose. The results suggest that lactose hydrolysis is the rate limiting step in the overall absorption of glucose from lactose in vitro, and that the relationship between hydrolysis and absorption is the same in normal subjects and in hypolactasic subjects. PMID:3084346
Lactose absorption and mucosal disaccharidases in convalescent pellagra and kwashiorkor children
Prinsloo, J. G.; Wittmann, W.; Kruger, H.; Freier, E.
1971-01-01
Oral lactose and glucose/galactose loading tests were done in Bantu children convalescing from kwashiorkor and pellagra. Small bowel biopsies and disaccharidase estimations were performed in all except 2 patients. Lactose absorption was more impaired and intestinal lactase levels were lower in the pellagra than in the kwashiorkor group. The fact that diarrhoea after admission to hospital was less common in pellagra than kwashiorkor was ascribed to a lesser lactose load due to the early introduction of a mixed diet in the former group, in comparison with milk feeds only in the latter group. The absence of troublesome diarrhoea while on moderate quantities of lactose in the diet, in the presence of low intestinal lactase levels, but evidence of lactose malabsorption after loading, has a bearing on preventive and therapeutic nutrition programmes in non-Caucasian children. Lactase deficiency is not necessarily synonymous with symptomatic lactose intolerance if the threshold is not exceeded. Concern is expressed that excessive caution against the use of milk may lead to a worsening of infantile malnutrition in developing countries. PMID:5109409
Vandenplas, Yvan
2015-01-01
Lactose is the main carbohydrate in infant feeding, but its impact decreases as the child gets older and consumes less milk and dairy products. Congenital lactose intolerance is a very rare condition. However, lactase activity may be low and need to mature during the first weeks of life in many infants. However, the evidence that unabsorbed lactose is causing infantile crying and colic is contradictory. Unabsorbed lactose has a bifidogenic effect and improves calcium absorption. Lactose malabsorption may occur secondary and thus temporally to other etiologies such as infectious gastroenteritis, cow's milk allergy and celiac disease. One the cause is treated, lactase activity will gradually return to normal. The vast majority of Asian children will develop late onset congenital lactase deficiency. However, this entity only exceptionally causes symptoms before the age of 4-5 years. Symptoms are abdominal cramps, flatulence and watery, acid stools, and decrease the quality of life but lactose intolerance is not associated with "true disease". The diagnosis is made on clinical grounds and confirmed with a lactose breath test, if needed. These patients need to have a lifetime long reduced lactose intake to improve their quality of life.
Genome flux and stasis in a five millennium transect of European prehistory
Gamba, Cristina; Jones, Eppie R.; Teasdale, Matthew D.; McLaughlin, Russell L.; Gonzalez-Fortes, Gloria; Mattiangeli, Valeria; Domboróczki, László; Kővári, Ivett; Pap, Ildikó; Anders, Alexandra; Whittle, Alasdair; Dani, János; Raczky, Pál; Higham, Thomas F. G.; Hofreiter, Michael; Bradley, Daniel G; Pinhasi, Ron
2014-01-01
The Great Hungarian Plain was a crossroads of cultural transformations that have shaped European prehistory. Here we analyse a 5,000-year transect of human genomes, sampled from petrous bones giving consistently excellent endogenous DNA yields, from 13 Hungarian Neolithic, Copper, Bronze and Iron Age burials including two to high (~22 × ) and seven to ~1 × coverage, to investigate the impact of these on Europe’s genetic landscape. These data suggest genomic shifts with the advent of the Neolithic, Bronze and Iron Ages, with interleaved periods of genome stability. The earliest Neolithic context genome shows a European hunter-gatherer genetic signature and a restricted ancestral population size, suggesting direct contact between cultures after the arrival of the first farmers into Europe. The latest, Iron Age, sample reveals an eastern genomic influence concordant with introduced Steppe burial rites. We observe transition towards lighter pigmentation and surprisingly, no Neolithic presence of lactase persistence. PMID:25334030
Genome flux and stasis in a five millennium transect of European prehistory.
Gamba, Cristina; Jones, Eppie R; Teasdale, Matthew D; McLaughlin, Russell L; Gonzalez-Fortes, Gloria; Mattiangeli, Valeria; Domboróczki, László; Kővári, Ivett; Pap, Ildikó; Anders, Alexandra; Whittle, Alasdair; Dani, János; Raczky, Pál; Higham, Thomas F G; Hofreiter, Michael; Bradley, Daniel G; Pinhasi, Ron
2014-10-21
The Great Hungarian Plain was a crossroads of cultural transformations that have shaped European prehistory. Here we analyse a 5,000-year transect of human genomes, sampled from petrous bones giving consistently excellent endogenous DNA yields, from 13 Hungarian Neolithic, Copper, Bronze and Iron Age burials including two to high (~22 × ) and seven to ~1 × coverage, to investigate the impact of these on Europe's genetic landscape. These data suggest genomic shifts with the advent of the Neolithic, Bronze and Iron Ages, with interleaved periods of genome stability. The earliest Neolithic context genome shows a European hunter-gatherer genetic signature and a restricted ancestral population size, suggesting direct contact between cultures after the arrival of the first farmers into Europe. The latest, Iron Age, sample reveals an eastern genomic influence concordant with introduced Steppe burial rites. We observe transition towards lighter pigmentation and surprisingly, no Neolithic presence of lactase persistence.
Furnari, Manuele; Bonfanti, Daria; Parodi, Andrea; Franzè, Jolanda; Savarino, Edoardo; Bruzzone, Luca; Moscatelli, Alessandro; Di Mario, Francesco; Dulbecco, Pietro; Savarino, Vincenzo
2013-02-01
A lactose breath test (LBT) is usually used to diagnose lactase deficiency, and a lactose quick test (LQT) has been proposed as a new test on duodenal biopsies to detect this disorder. We aimed to assess the diagnostic accuracy of LBT and LQT and their ability to predict the clinical response to a lactose-free diet in patients with self-reported lactose intolerance. Fifty-five patients (age 47 ± 14 y; M/F 15/36) underwent upper gastrointestinal endoscopy and 25g-LBT. Two duodenal biopsies were taken to determine lactase deficiency (normal, mild, or severe) by LQT and to rule out other causes of secondary lactose malabsorption. Patients with a positive LBT and normal LQT also underwent a glucose breath test to exclude small intestinal bacterial overgrowth as a cause of the former result. The severity of gastrointestinal symptoms was measured with a GSS questionnaire, under basal condition and 1 month after a lactose-free diet. Lactose malabsorption was detected in 31/51 patients with LBT and in 37/51 patients with LQT (P = NS). Celiac disease was found in 2 patients. Two LBT+ patients showed a positive glucose breath test for small intestinal bacterial overgrowth. Eight patients had a mild hypolactasia by LQT and a negative LBT, but they had a significant improvement of symptoms after diet. LQT and LBT were concordant in 83% of cases and predicted the response to a lactose-free diet in 98% and 81% of the cases, respectively (P = 0.03). LQT is as sensitive as LBT in detecting lactase deficiency; however, it seems to be more accurate than LBT in predicting the clinical response to a lactose-free diet.
[Determination of lactose intolerance frequency in children with food allergy].
Hutyra, Tomasz; Iwańczak, Barbara
2008-10-01
Lactose malabsorption and lactose intolerance symptoms are the most common alimentary tract disorders in children. Lactose intolerance is a result of lactase deficiency or lack of lactase and lactose malabsorption. Hypersensitivity in food allergy is connected with the presence of specific IgE (specific antibodies against some allergens) or lymphocytes. Lactose intolerance and food allergy may coexist in the same patient. The aim of this study was determination of lactose intolerance frequency in children with food allergy who were below and above 5 years of age. The number of 87 children with food allergy aged from 0.7 to 18 years were included in the study (48 boys and 39 girls). 51 patients above 5 years of age and 36 patients below 5 years of age were studied. Lactose intolerance symptoms, hydrogen breath test, activity of lactase and villous atrophy were investigated. Decreased absorption of lactose in hydrogen breath test was observed in 28% of children above 5 years of age and in 5% in younger children. Positive result of biological trial in hydrogen breath test was observed in 10% of patients who were below 5 years of age and in 26% patients above 5 years. There was no statistically significant difference in lactose intolerance frequency and in decreased activity of lactase in intestinal mucosa between these two groups. Frequent partial villous atrophy was observed in younger patients (41,38%) than in children above 5 years of age (17.86%). Lactose intolerance was observed in 10% patients who were below 5 years of age and in 26% patients above 5 years of age with food allergy. There was no statistically significant difference between these two groups.
[Lactose intolerance in neonates with non-infectious diarrhea].
Su, Hui-Min; Jiang, Yi; Hu, Yu-Lian; Yang, Hui; Dong, Tian-Jin
2016-04-01
To investigate the development of lactose intolerance in neonates with non-infectious diarrhea and its association with diarrhea, and to evaluate the diagnostic values of fecal pH value and urine galactose determination for neonatal lactase deficiency. Seventy hospitalized neonates who developed non-infectious diarrhea between October 2012 and June 2015 were enrolled as the diarrhea group, and 162 hospitalized neonates without non-infectious diarrhea were enrolled as the non-diarrhea group. Test paper was used to determine fecal pH value. The galactose oxidase method was used to detect urine galactose. The neonates with positive galactose oxidase were diagnosed with lactase deficiency, and those with lactase deficiency and diarrhea were diagnosed with lactose intolerance. According to the results of urine galactose detection, 69 neonates in the diarrhea group who underwent urine galactose detection were classified into lactose intolerance group (45 neonates) and lactose tolerance group (24 neonates), and their conditions after treatment were compared between the two groups. The follow-up visits were performed for neonates with diarrhea at 3 months after discharge. Fecal pH value and positive rate of urine galactose (65% vs 54%) showed no significant differences between the diarrhea and non-diarrhea groups (P>0.05). Fecal pH value showed no significant difference between the lactose intolerance and lactose tolerance groups (P>0.05), while the neonates in the lactose intolerance group had a significantly longer time to recovery of defecation than those in the lactose tolerance group (P<0.05). The incidence of lactase deficiency is high in neonates, and diarrhea due to lactose intolerance tends to occur. Determination of fecal pH value has no significance in the diagnosis of lactose intolerance in neonates with diarrhea.
Jonckheere, Leander; Schelstraete, Petra; Van Simaey, Leen; Van Braeckel, Eva; Willekens, Julie; Van Daele, Sabine; De Baets, Frans; Vaneechoutte, Mario
2018-04-11
After antibiotic eradication treatment for a first ever Pseudomonas aeruginosa isolation, the European consensus criteria (ECC) are widely used to assess colonization status with P. aeruginosa in CF-patients. We evaluated to what extent genotyping (GT) of subsequent P. aeruginosa isolates could predict/assess chronic colonization (CC), in comparison with the ECC. Over a 14-year period, sputa were cultured from 80 CF-patients (age range: 2-51 years), from a first ever isolation of P. aeruginosa onwards. Patients with a positive culture for P. aeruginosa received antibiotic eradication treatment. For the 40 patients for whom three or more P. aeruginosa isolates were available, these isolates were genotyped. According to the ECC, 27 out of the 40 patients (67.5%) became CC during the study period (ECC-positive patients). Genotyping confirmed persistence of the same genotype for 25 of these ECC-positive patients. Genotyping indicated persistence of the same genotype for at least two subsequent isolates for 5 out of 13 ECC-negative patients. Culture-positivity characteristics of the 27 ECC-positive patients corresponded well to those of the 30 GT-positive patients, with an overall higher number of positive cultures as well as a shorter interval in between first and second isolate compared to ECC-negative and GT-negative patients. Genotyping indicated persistence of the same genotype on average 9.3 months earlier than CC according to the ECC (P < 0.01). Genotyping of P. aeruginosa isolates confirmed CC for 25 out of 27 ECC-positive patients (92.6% specificity) and predicted CC 9.3 months earlier than the ECC. Copyright © 2018 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.
Smith, Caren E; Coltell, Oscar; Sorlí, Jose V; Estruch, Ramón; Martínez-González, Miguel Ángel; Salas-Salvadó, Jordi; Fitó, Montserrat; Arós, Fernando; Dashti, Hassan S; Lai, Chao Q; Miró, Leticia; Serra-Majem, Lluís; Gómez-Gracia, Enrique; Fiol, Miquel; Ros, Emilio; Aslibekyan, Stella; Hidalgo, Bertha; Neuhouser, Marian L; Di, Chongzhi; Tucker, Katherine L; Arnett, Donna K; Ordovás, José M; Corella, Dolores
2016-09-14
Controversy persists on the association between dairy products, especially milk, and cardiovascular diseases (CVD). Genetic proxies may improve dairy intake estimations, and clarify diet-disease relationships through Mendelian randomization. We meta-analytically (n ≤ 20,089) evaluated associations between a lactase persistence (LP) SNP, the minichromosome maintenance complex component 6 (MCM6)-rs3754686C>T (nonpersistence>persistence), dairy intake, and CVD biomarkers in American (Hispanics, African-American and Whites) and Mediterranean populations. Moreover, we analyzed longitudinal associations with milk, CVD and mortality in PREDIMED), a randomized Mediterranean diet (MedDiet) intervention trial (n = 7185). The MCM6-rs3754686/MCM6-rs309180 (as proxy), LP-allele (T) was strongly associated with higher milk intake, but inconsistently associated with glucose and lipids, and not associated with CVD or total mortality in the whole population. Heterogeneity analyses suggested some sex-specific associations. The T-allele was associated with higher CVD and mortality risk in women but not in men (P-sex interaction:0.005 and 0.032, respectively), mainly in the MedDiet group. However, milk intake was not associated with CVD biomarkers, CVD or mortality either generally or in sub-groups. Although MCM6-rs3754686 is a good milk intake proxy in these populations, attributing its associations with CVD and mortality in Mediterranean women to milk is unwarranted, as other factors limiting the assumption of causality in Mendelian randomization may exist.
Lin, Gigin; Lai, Chyong-Huey; Tsai, Shang-Yueh; Lin, Yu-Chun; Huang, Yu-Ting; Wu, Ren-Chin; Yang, Lan-Yan; Lu, Hsin-Ying; Chao, Angel; Wang, Chiun-Chieh; Ng, Koon-Kwan; Ng, Shu-Hang; Chou, Hung-Hsueh; Yen, Tzu-Chen; Hung, Ji-Hong
2017-03-01
To assess the clinical value of proton ( 1 H) MR spectroscopy in cervical carcinomas, in the prediction of poor prognostic human papillomavirus (HPV) genotypes as well as persistent disease following concurrent chemoradiotherapy (CCRT). 1 H MR spectroscopy using external phase array coil was performed in 52 consecutive cervical cancer patients at 3 Tesla (T). Poor prognostic HPV genotypes (alpha-7 species or absence of HPV infection) and persistent cervical carcinoma after CCRT were recorded. Statistical significance was calculated with the Mann-Whitney two-sided nonparametric test and areas under the receiver operating characteristics curve (AUC) analysis. A 4.3-fold (P = 0.032) increased level of methyl resonance at 0.9 ppm was found in the poor prognostic HPV genotypes, mainly attributed to the presence of HPV18, with a sensitivity of 75%, a specificity of 81%, and an AUC of 0.76. Poor prognostic HPV genotypes were more frequently observed in patients with adeno-/adenosquamous carcinoma (Chi-square, P < 0.0001). In prediction of the four patients with persistent disease after CCRT, elevated methyl resonance demonstrated a sensitivity of 100%, a specificity of 74%, and an AUC of 0.82. 1 H MR spectroscopy at 3T can be used to depict the elevated lipid resonance levels in cervical carcinomas, as well as help to predict the poor prognostic HPV genotypes and persistent disease following CCRT. Further large studies with longer follow up times are warranted to validate our initial findings. 1 J. Magn. Reson. Imaging 2017;45:899-907. © 2016 International Society for Magnetic Resonance in Medicine.
Geisler, W M; Black, C M; Bandea, C I; Morrison, S G
2008-12-01
To investigate the relationship of Chlamydia trachomatis (CT) outer membrane protein A (OmpA) type to the clearance of CT infection before treatment. CT OmpA genotyping, with amplification and sequencing of ompA, was utilised to study the natural history of CT infection (spontaneous resolution vs persistence) in 102 individuals with chlamydia-positive screening tests returning for treatment. CT OmpA distribution was associated with spontaneous resolution of CT, most notably with CT OmpA genotype J/Ja detected more often from the initial screening CT test than other genotypes in those who then had spontaneous resolution of CT noted at the time of treatment. Five individuals with presumed persisting CT infection had discordant CT OmpA genotypes at the screening and treatment visits, suggesting possible new interval CT infection. Clearance of chlamydia by the host before treatment may be influenced by the CT OmpA genotype infecting the host. CT OmpA genotyping may be a valuable tool in understanding the natural history of chlamydial infections.
The molecular basis of lactose intolerance.
Campbell, Anthony K; Waud, Jonathan P; Matthews, Stephanie B
2009-01-01
A staggering 4000 million people cannot digest lactose, the sugar in milk, properly. All mammals, apart from white Northern Europeans and few tribes in Africa and Asia, lose most of their lactase, the enzyme that cleaves lactose into galactose and glucose, after weaning. Lactose intolerance causes gut and a range of systemic symptoms, though the threshold to lactose varies considerably between ethnic groups and individuals within a group. The molecular basis of inherited hypolactasia has yet to be identified, though two polymorphisms in the introns of a helicase upstream from the lactase gene correlate closely with hypolactasia, and thus lactose intolerance. The symptoms of lactose intolerance are caused by gases and toxins produced by anaerobic bacteria in the large intestine. Bacterial toxins may play a key role in several other diseases, such as diabetes, rheumatoid arthritis, multiple sclerosis and some cancers. The problem of lactose intolerance has been exacerbated because of the addition of products containing lactose to various foods and drinks without being on the label. Lactose intolerance fits exactly the illness that Charles Darwin suffered from for over 40 years, and yet was never diagnosed. Darwin missed something else--the key to our own evolution--the Rubicon some 300 million years ago that produced lactose and lactase in sufficient amounts to be susceptible to natural selection.
[Lactose intolerance: past and present. Part 1].
Buzás, György Miklós
2015-09-20
Lactose intolerance is the most prevalent intestinal malabsorption disorder. After presentation of its history, the author describes the emergence of lactose intolerance during the evolution of species, and the biochemistry of lactose as well as features of human and bacterial lactase enzymes are then described. The unequal distribution of lactose intolerance in different continents and population is discussed, followed by presentation of past and present prevalence data in Hungary. Adult-type hypolactasia is caused by a polymorphism of the MCM6 gene located upstream from the lactase gene on the long arm of the chromosome 2. It can be determined with the polymerase chain reaction. The intestinal symptoms of lactose intolerance are well known, but its extra-intestinal manifestations are less recognised. Invasive diagnostic methods (determination of lactase activity from small intestinal biopsies, lactose tolerance test), are accurate, but have been replaced by the non-invasive methods; their gold standard is the H2 breath test. Genetic testing is being used more and more frequently in Hungary too, and, presumably, the methane breath test will be also available in the near future. Lactose intolerance can be accompanied by inflammatory bowel diseases, coeliac disease and irritable bowel syndrome; it could be established whether this association is causal or not in order to start a correct diet and therapy.
Francesconi, Carlos Fernando de Magalhães; Machado, Marta Brenner; Steinwurz, Flavio; Nones, Rodrigo Bremer; Quilici, Flávio Antonio; Catapani, Wilson Roberto; Miszputen, Sender Jankiel; Bafutto, Mauro
2016-01-01
Primary hypolactasia is a common condition where a reduced lactase activity in the intestinal mucosa is present. The presence of abdominal symptoms due to poor absorption of lactose, which are present in some cases, is a characteristic of lactose intolerance. Evaluate the efficacy of a product containing exogenous lactase in tablet form compared to a reference product with proven effectiveness in patients with lactose intolerance. Multicentre, randomized, parallel group, single-blind, comparative non-inferiority study. One hundred twenty-nine (129) adult lactose intolerance patients with hydrogen breath test results consistent with a diagnosis of hypolactasia were randomly assigned to receive the experimental product (Perlatte(r) - Eurofarma Laboratórios S.A.) or the reference product (Lactaid(r) - McNeilNutritionals, USA) orally (one tablet, three times per day) for 42 consecutive days. Data from 128 patients who actually received the studied treatments were analysed (66 were treated with the experimental product and 62 with the reference product). The two groups presented with similar baseline clinical and demographic data. Mean exhaled hydrogen concentration tested at 90 minutes after the last treatment (Day 42) was significantly lower in the experimental product treated group (17±18 ppm versus 34±47 ppm) in the per protocol population. The difference between the means of the two groups was -17 ppm (95% confidence interval [95% CI]: -31.03; -3.17). The upper limit of the 95% CI did not exceed the a priori non-inferiority limit (7.5 ppm). Secondary efficacy analyses confirmed that the treatments were similar (per protocol and intention to treat population). The tolerability was excellent in both groups, and there were no reports of serious adverse events related to the study treatment. The experimental product was non-inferior to the reference product, indicating that it was an effective replacement therapy for endogenous lactase in lactose intolerance patients.
Lactose (mal)digestion evaluated by the 13C-lactose digestion test.
Vonk, R J; Lin, Y; Koetse, H A; Huang, C; Zeng, G; Elzinga, H; Antoine, J; Stellaard, F
2000-02-01
The prevalence of genetically determined lactase nonpersistence is based on the results of the lactose H2 breath test. This test, however, is an indirect test, which might lead to misinterpretation. We determined lactase activity in healthy Chinese and Dutch students using a novel 13C-lactose digestion test. The cut-off value of this test was established in a Chinese population with a homogenous genetic background of lactase nonpersistence and was compared with the results obtained in a Caucasian population. Twenty-five grams of a 13C-lactose solution was consumed by 12 known H2-positive and 5 H2-negative Chinese students and 48 Dutch students and, subsequently, 13C-glucose concentration in plasma and H2 excretion in breath were measured. A similar 13C-glucose response curve was found in all Chinese students. The mean response curve in the Dutch students was more pronounced (P < 0.01). The 1 h (peak) plasma 13C-glucose concentration was the best discriminator between lactose digesting and maldigesting subjects. The cut-off level of 2 mmol L-1 13C-glucose in plasma was defined in the H2-positive Chinese students group. Based on the 13C-glucose response the prevalence of lactose maldigestion in the Dutch subjects was 25%; based on the lactose H2 breath test 17%. Using the 13C-lactose digestion test the results demonstrate a higher prevalence of lactose maldigestion in a Caucasian population than indicated by the results of the H2 breath test. A moderate increase in the plasma 13C-glucose concentration after consumption of 13C-lactose in the young adult Chinese subjects indicates a residual lactase activity in that age group, even when a positive H2 breath test result is obtained. These results indicate that the 13C-glucose concentration in plasma more accurately reflects the small intestinal lactose digestion capacity than the lactose H2 breath test.
Devloo, R; Martel, A; Hellebuyck, T; Vranckx, K; Haesebrouck, F; Pasmans, F
2011-06-02
Devriesea agamarum causes dermatitis and septicaemia in a variety of lizards, notably those belonging to the genus Uromastyx, whereas other species such as bearded dragons (Pogona vitticeps) seem to be asymptomatic carriers. Using amplified fragment length polymorphism (AFLP), the relatedness between 69 D. agamarum isolates was examined. The isolates derived from 44 diseased lizards, of which 31 belonged to the genus Uromastyx, and from 25 healthy lizards, of which 21 were bearded dragons. Eight AFLP genotypes were obtained, four of which comprised 93% of the isolates. These four genotypes were each present in 2, 2, 8 and 13 different captive colonies. Up to three genotypes were isolated from a single infected colony simultaneously. On two occasions, the same genotype was found in healthy bearded dragons and diseased Uromastyx lizards from the same colony, confirming the role of the former as an asymptomatic source of infection for the latter. Two genotypes, comprising 12 isolates, were exclusively associated with diseased Uromastyx lizards, suggesting strain dependent host adaptation. Finally, D. agamarum was shown to be able to persist for at least seven years in a lizard colony, persistently causing severe disease in several lizard species. Copyright © 2011 Elsevier B.V. All rights reserved.
ABO Blood Type and Personality Traits in Healthy Japanese Subjects.
Tsuchimine, Shoko; Saruwatari, Junji; Kaneda, Ayako; Yasui-Furukori, Norio
2015-01-01
There is no scientific consensus that a relationship exists between the ABO blood group and personality traits. However, a recent study hypothesized that the dopamine beta-hydroxylase (DBH) gene is in linkage with the ABO gene. The sample population consisted of 1,427 healthy Japanese subjects who completed the Temperament and Character Inventory (TCI). Each subject's ABO blood type was determined by genotyping the rs8176719 and rs8176746 ABO gene single-nucleotide polymorphisms (SNPs) using a TaqMan genotyping assay. The relationships between the six ABO genotypes or four ABO phenotypes and personality traits were examined using a multivariate analysis of covariance (MANCOVA), controlling for age and sex. The MANCOVA data showed a significant difference in TCI scores among the ABO genotype groups (F [7, 1393] = 3.354, p = 0.001). A subsequent univariate analysis showed a significant difference in the mean scores for Persistence among the genotype groups (F = 2.680, partial η2 = 0.010, p = 0.020). Similarly, dividing the ABO blood type into four phenotypes revealed a significant difference among the phenotype groups (F [7, 1397] = 2.529, p = 0.014). A subsequent univariate analysis showed a significant difference among the phenotype groups in the mean scores for Persistence (F = 2.952, partial η2= 0.006, p = 0.032). We observed a significant association between ABO blood group genotypes and personality traits in a large number of healthy Japanese subjects. However, these results should be regarded as preliminary and should be interpreted with caution because it is possible that the association between ABO blood group genotype and the Persistence trait is relatively weak.
Selection of alfalfa genotypes for resistance to the foliar pathogen Curvularia geniculata.
Ávila, Mariana R; Dall'agnol, Miguel; Martinelli, José A; Silva, Gerarda B P DA; Bremm, Carolina; Nunes, Tamyris
2017-01-01
Foliar diseases impose severe restrictions on the persistence and productivity of Medicago sativa, both of which may be increased by developing disease resistant and more competitive genotypes that can improve pasture quality. We found Curvularia geniculata as the principal alfalfa foliar pathogen in the Brazilian state of Rio Grande do Sul (RS). Growth chamber experiments evaluated the resistance of alfalfa genotypes 'E1C4', 'CPPSul', 'ABT 805' and 'CUF-101' to C. geniculata as compared the control 'Crioula' genotype. These genotypes were also evaluated in field trials at a sea level site in Eldorado do Sul in central RS and at two sites £200 m above sea level, one in Bagé municipality in south west RS and the other at a farm near the town of Alto Feliz in north east RS. Plants were spray-inoculated with 1.6 x 106 ml-1 of C. geniculata spores and visually evaluated for leaf damage 14 days later. The C. geniculata infection rates varied from zero to 100%. Alfalfa persistence and forage mean dry mass (DM) production at the Eldorado site were measured during different seasons from November 2013 to January 2015 by calculating the incidence of invasive plants and morphologically separating leaves from stems and calculating both leaf and stem DM. Data were analysed using mixed statistical models. The best results for persistence and forage DM were shown by the 'CPPSul' genotypes (DM = 16,600 kg ha-1) and 'Crioula' (DM = 15,750 kg ha-1). These two genotypes will be used for subsequent investigations and selection cycles.
Ibba, Ivan; Gilli, Agnese; Boi, Maria Francesca; Usai, Paolo
2014-01-01
To establish whether supplementation with a standard oral dose of Beta-Galactosidase affects hydrogen breath excretion in patients presenting with lactose malabsorption. Ninety-six consecutive patients positive to H2 Lactose Breath Test were enrolled. Mean peak H2 levels, the time to reach the peak H2, the time to reach the cut-off value of 20 ppm, the cumulative breath H2 excretion, the areas under the curve, and a Visual Analogical 10-point Scale for symptoms were calculated. Genotyping of the C/T-13910 variant was carried out. Following the oral administration of Beta-Galactosidase, in 21.88% of the cases, H2 Lactose Breath Test became negative (Group A), while mean peak H2 levels (74.95 ppm versus 7.85), P < 0.0000, in 17.71% (Group B) were still positive, with the H2 level 20 ppm above the baseline, but the peak H2 levels were significantly lower than those observed at the baseline test (186.7 ppm versus 66.64), P < 0.0000, while in 60.41% (Group C) they were still positive with the peak H2 levels similar to those observed at the baseline test (94.43 versus 81.60 ppm). All 96 individuals tested presented the C/C-13910 genotype nonpersistence. The response to oral administration of Beta-Galactosidase in patients with symptoms of lactose malabsorption presents a significant variability.
Vilotte, Jean-Luc
2002-01-01
Lactose is the major sugar present in milk and an important osmotic regulator of lactation. It is digested by intestinal lactase, an enzyme expressed in new-borns. Its activity declines following weaning. As a result, adult mammals are normally lactose-intolerant and more than 75% of the human adult population suffers from lactase deficiency. A reduction in milk lactose content could be beneficial for nutritional but also agricultural and industrial purposes (less volume to transport, better milk coagulation, less effluent production). Several attempts to create transgenic mice producing milk with modified carbohydrate compositions have recently been described. Depending on whether these modifications resulted from an alteration of lactose synthesis or from lactose hydrolysis, striking physiological differences are observed.
Sanchez, Inma; Garcia-Nuñez, Marian; Ragull, Sonia; Sopena, Nieves; Pedro-Botet, Maria Luisa; Estere, Maria; Rey-Joly, Celestino; Sabria, Miquel; Esteve, Maria
2008-02-01
Genotypic variability and clonal persistence are important concepts in molecular epidemiology as they facilitate the search for the source of sporadic cases or outbreaks of legionellosis. We studied the genotypic variability and persistence of Legionella pulsed-field gel electrophoresis (PFGE) patterns over time (period > 6 months) in 34 positive cooling towers from two different areas. In area A, radius of 70 km, 52 indistinguishable PFGE patterns were differentiated among the 27 cooling towers. In 13 cooling towers we observed >or= 2 PFGE patterns. Each cooling tower had its own indistinguishable Legionella PFGE pattern which was not shared with any other cooling tower. In area B, radius of 1 km, 10 indistinguishable PFGE patterns were obtained from the seven cooling towers. In four, we observed >or= 2 PFGE patterns. Three of these 10 indistinguishable PFGE patterns were shared by more than one cooling tower. In 27 of 34 cooling towers the same PFGE pattern was recovered after 6 months to up to 5 years of follow-up. The large genotypic diversity of Legionella observed in the cooling towers aids in the investigation of community outbreaks of Legionnaires' disease. However, shared patterns in small areas may confound the epidemiological investigation. The persistence of some PFGE patterns in cooling towers makes the recovery of the Legionella isolate causing the outbreak possible over time.
Changes in Body Mass Index, Leptin, and Leptin Receptor Polymorphisms and Breast Cancer Risk.
Liu, Chun-Rong; Li, Qin; Hou, Can; Li, Hui; Shuai, Ping; Zhao, Min; Zhong, Xiao-Rong; Xu, Zhu-Ping; Li, Jia-Yuan
2018-03-01
Obesity is a strong risk factor for breast cancer. The polymorphisms of leptin (LEP) and leptin receptor (LEPR) may be associated with breast cancer by regulator of adipose tissue mass and tumor cell growth. A total of 794 cases and 805 matched controls were sequentially enrolled. Time-of-flight mass spectrometry was used to determine the LEPrs7799039, LEPRrs1137100, and LEPRrs1137101 genotypes for each participant. Associations between polymorphisms of these genes, change in body mass index (BMI), and breast cancer risk were assessed by unconditional multivariable logistic regression models. The unconditional logistic regression model showed that persistent overweight (BMI ≥24 kg/m 2 ) over the preceding 10 years was associated with increased breast cancer risk in premenopausal women (odds ratio [OR] = 1.67, 95% confidence interval [CI]: 1.19-2.35). No associations between LEPrs7799039, LEPRrs1137100, or LEPRrs1137101 polymorphisms alone and breast cancer risk were found. Persistent overweight over the preceding 10 years and carrying the LEPrs7799039 AA genotype together increased breast cancer risk in premenopausal women (OR adj = 2.00, 95% CI: 1.26-3.16). Persistent overweight over the preceding 10 years and carrying the LEPRrs1137100 GG genotype increased breast cancer risk in premenopausal women (OR adj = 1.68, 95% CI: 1.06-2.68). In premenopausal women, persistent overweight (BMI ≥24 kg/m 2 ) over the preceding 10 years increases breast cancer risk. Persistent overweight along with LEPrs7799039 AA or LEPRrs1137100 GG genotypes synergistically increase risk of breast cancer among premenopausal women.
... tract from stool and changes it from a liquid to a solid form. In the colon, bacteria break down undigested lactose and create fluid and gas. Not all people with lactase deficiency and lactose ...
Bogani, Giorgio; Ditto, Antonino; Martinelli, Fabio; Signorelli, Mauro; Chiappa, Valentina; Leone Roberti Maggiore, Umberto; Taverna, Francesca; Lombardo, Claudia; Borghi, Chiara; Scaffa, Cono; Lorusso, Domenica; Raspagliesi, Francesco
2018-01-22
The objective of this study was to determine whether the pretreatment human papillomavirus (HPV) genotype might predict the risk of cervical dysplasia persistence/recurrence. Retrospective analysis of prospectively collected data of consecutive 5104 women who underwent the HPV-DNA test were matched with retrospective data of women undergoing either follow-up or medical/surgical treatment(s) for genital HPV-related infection(s). Artificial neuronal network (ANN) analysis was used in order to weight the importance of different HPV genotypes in predicting cervical dysplasia persistence/recurrence. ANN simulates a biological neuronal system from both the structural and functional points of view: like neurons, ANN acquires knowledge through a learning-phase process and allows weighting the importance of covariates, thus establishing how much a variable influences a multifactor phenomenon. Overall, 5104 women were tested for HPV. Among them, 1273 (25%) patients underwent treatment for HPV-related disorders. LASER conization and cervical vaporization were performed in 807 (59%) and 386 (30%) patients, respectively, and secondary cervical conization in 45 (5.5%). ANN technology showed that the most important genotypes predicting cervical dysplasia persistence/recurrence were HPV-16 (normalized importance: 100%), HPV-59 (normalized importance: 51.2%), HPV-52 (normalized importance: 47.7%), HPV-18 (normalized importance: 32.8%) and HPV-45 (normalized importance: 30.2%). The pretreatment diagnosis of all of those genotypes, except HPV-45, correlated with an increased risk of cervical dysplasia persistence/recurrence; the pretreatment diagnosis was also arrived at using standard univariate and multivariable models (P<0.01). Pretreatment positivity for HPV-16, HPV-18, HPV-52 and HPV-59 might correlate with an increased risk of cervical dysplasia persistence/recurrence after treatment. These data might be helpful during patients' counseling and to implement new vaccination programs.
Floreani, Annarosa; Cazzagon, Nora; Boemo, Deris Gianni; Baldovin, Tatjana; Baldo, Vincenzo; Egoue, Joel; Antoniazzi, Sara; Minola, Eliseo
2011-11-01
Patients with chronic hepatitis C and persistently normal alanine transaminase levels have recently been included in the guidelines for antiviral treatment. To evaluate the efficacy of PEG-interferon α-2a and weight-based ribavirin doses in patients with these characteristics in a single Italian centre. Patients with chronic hepatitis C and at least three normal alanine transaminase values over a 12-month period were offered a treatment with PEG-interferon α-2a 180 mg/week and ribavirin (800 mg/day for weight <60 kg; 1000 mg/day for weight >60 and <75 kg; 1200 mg/day for weight >75 kg) for 24 weeks (according to genotype 2 or 3) or for 48 weeks (according to genotype 1 or 4). Each patient at baseline underwent liver stiffness (LS) examination using Fibroscan. Data were analysed according to the intention-to-treat criteria. A total of 227 patients (55 men, 172 women) were enrolled into the study: 65 (28.6%) had genotype 1, 144 (63.4%) genotype 2, nine (4.0%) genotype 3 and nine (4.0%) genotype 4. Patients with genotype 2 or 3 (N=153 with easy genotypes) were allocated in group 1 and those with genotype 1 or 4 (N=74 with difficult genotypes) in group 2. According to the LS measurement, patients were classified as follows: 159 (70.0%) presented absent or mild fibrosis (LS=2.5-7.0 kPa), 61 (26.9%) patients had significant fibrosis (LS=7.1-9.5) and seven (3.1%) patients had severe fibrosis (LS >9.6). Twelve patients (5.3%) dropped out within 4 months because of side-effects, whereas 215 patients completed the study. Overall, 13 patients were considered nonresponders (5.7%) and six patients (2.6%) were relapsers to the therapy. The sustained virological response (SVR) rate was 85.4% and it was higher in 'easy' genotypes (2 or 3) compared with 'difficult' genotypes (1 or 4) (92.2 vs. 74.3%, P<0.001). No statistical difference was found in the SVR rate between patients presenting absent or mild fibrosis as against those with significant fibrosis. Multivariate analysis, including factors correlated with SVR, showed that easy genotype and female sex are significantly associated with a SVR. Patients with chronic hepatitis C and persistently normal transaminases have an 85.4% chance to clear the virus with conventional antiviral treatment. Female patients in fertile age with easy genotypes have a 100% chance to reach a SVR.
Problems Digesting Dairy Products?
... contains Bifidobacteria, they claim these microorganisms are beneficial (probiotic) and create their own lactase, which helps people ... fecal matter (animal manure) and are not considered probiotic, but instead are regarded as contaminants." Drinking raw ...
Wang, C L; Lang, X; Wu, P J; Casper, D P; Li, F D
2017-08-01
Growth depends on an animal's capacity to digest and assimilate ingested nutrients, and insufficient supply and impairment will constrain lamb growth. Eight groups of Alpine Finewool lambs were harvested on 0, 3, 7, 14, 21, 28, 42, and 56 d to measure pH and enzymatic activities in the duodenum, proximal jejunum, middle jejunum, distal jejunum, and ileum mucosa or digesta. From the duodenum to the ileum the pH of intestinal mucosa and digesta increased, whereas pH changed very little with age. The trypsin, chymotrypsin, lipase, lactase, and α-amylase activities observed at birth decreased by d 3, followed by a nonuniform enzymatic response in the small intestine. The trypsin activity increased from d 3 to peak, at d 21, followed by a decline. Chymotrypsin activity followed the same general trend but with smaller responses in activities. Trypsin demonstrated greater enzymatic activity than chymotrypsin at the same age. The lipase activity of small intestinal mucosa and digesta changed little with age. The lactase activity was high at birth, decreased by d 3, and then increased, followed by a decrease as lambs approached weaning. α-Amylase activity was similar in the small intestinal mucosa and digesta at birth but increased with age for the duodenum and proximal jejunum. Plasma concentrations of cholecystokinin (CCK), secretin, and gastrin were positively correlated ( < 0.05) with ileal mucosa lipase activity. Plasma concentration of CCK, secretin, gastrin, and gastric inhibitory polypeptide (GIP) were positively correlated ( < 0.05) with ileal mucosa lactase activity. Plasma concentration of pancreatic polypeptide (PP) was negatively correlated ( < 0.05) with lactase activity in the middle jejunum and ileal mucosa. Plasma concentrations of CCK, secretin, gastrin, and GIP were positively correlated ( < 0.05) with α-amylase activity in the ileal mucosa but negatively correlated ( < 0.05) with duodenum, prejejunum, and middle jejunum. Plasma PP concentrations were positively correlated ( < 0.01) with α-amylase activity of duodenum, middle jejunum, and postjejunum mucosa but not with the enzyme activity of postjejunum and ileal mucosa ( > 0.05). Small intestinal enzymatic activities exist and may be sufficient to enhance lamb growth via appropriate nutrient supplementation.
21 CFR 184.1388 - Lactase enzyme preparation from Kluyveromyces lactis.
Code of Federal Regulations, 2014 CFR
2014-04-01
...) This enzyme preparation is derived from the nonpathogenic, nontoxicogenic yeast Kluyveromyces lactis... 683), which converts lactose to glucose and galactose. It is prepared from yeast that has been grown...
Impact of Pathogen Population Heterogeneity and Stress-Resistant Variants on Food Safety.
Abee, T; Koomen, J; Metselaar, K I; Zwietering, M H; den Besten, H M W
2016-01-01
This review elucidates the state-of-the-art knowledge about pathogen population heterogeneity and describes the genotypic and phenotypic analyses of persister subpopulations and stress-resistant variants. The molecular mechanisms underlying the generation of persister phenotypes and genetic variants are identified. Zooming in on Listeria monocytogenes, a comparative whole-genome sequence analysis of wild types and variants that enabled the identification of mutations in variants obtained after a single exposure to lethal food-relevant stresses is described. Genotypic and phenotypic features are compared to those for persistent strains isolated from food processing environments. Inactivation kinetics, models used for fitting, and the concept of kinetic modeling-based schemes for detection of variants are presented. Furthermore, robustness and fitness parameters of L. monocytogenes wild type and variants are used to model their performance in food chains. Finally, the impact of stress-resistant variants and persistence in food processing environments on food safety is discussed.
21 CFR 184.1388 - Lactase enzyme preparation from Kluyveromyces lactis.
Code of Federal Regulations, 2012 CFR
2012-04-01
..., nontoxicogenic yeast Kluyveromyces lactis (previously named Saccharomyces lactis). It contains the enzyme β... prepared from yeast that has been grown in a pure culture fermentation and by using materials that are...
21 CFR 184.1388 - Lactase enzyme preparation from Kluyveromyces lactis.
Code of Federal Regulations, 2013 CFR
2013-04-01
..., nontoxicogenic yeast Kluyveromyces lactis (previously named Saccharomyces lactis). It contains the enzyme β... prepared from yeast that has been grown in a pure culture fermentation and by using materials that are...
Immobilized Lactase in the Biochemistry Laboratory
NASA Astrophysics Data System (ADS)
Allison, Matthew J.; Bering, C. Larry
1998-10-01
Immobilized enzymes have many practical applications. They may be used in clinical, industrial, and biotechnological laboratories and in many clinical diagnostic kits. For educational purposes, use of immobilized enzymes can easily be taught at the undergraduate or even secondary level. We have developed an immobilized enzyme experiment that combines many practical techniques used in the biochemistry laboratory and fits within a three-hour time frame. In this experiment, lactase from over-the-counter tablets for patients with lactose intolerance is immobilized in polyacrylamide, which is then milled into small beads and placed into a chromatography column. A lactose solution is added to the column and the eluant is assayed using the glucose oxidase assay, available as a kit. We have determined the optimal conditions to give the greatest turnover of lactose while allowing the immobilized enzymes to be active for long periods at room temperature.
... a necessity for infants, who get all their nutrition from milk. As children replace milk with other foods, their lactase production normally decreases, but remains high enough to digest the amount of dairy in a typical adult diet. In primary lactose ...
... age 5. This is the age when our bodies may stop making lactase. In African Americans, the problem can occur as early as age 2. The condition is very common among adults with Asian, African, or Native American heritage. It is less ...
Adaptations to local environments in modern human populations.
Jeong, Choongwon; Di Rienzo, Anna
2014-12-01
After leaving sub-Saharan Africa around 50000-100000 years ago, anatomically modern humans have quickly occupied extremely diverse environments. Human populations were exposed to further environmental changes resulting from cultural innovations, such as the spread of farming, which gave rise to new selective pressures related to pathogen exposures and dietary shifts. In addition to changing the frequency of individual adaptive alleles, natural selection may also shape the overall genetic architecture of adaptive traits. Here, we review recent advances in understanding the genetic architecture of adaptive human phenotypes based on insights from the studies of lactase persistence, skin pigmentation and high-altitude adaptation. These adaptations evolved in parallel in multiple human populations, providing a chance to investigate independent realizations of the evolutionary process. We suggest that the outcome of adaptive evolution is often highly variable even under similar selective pressures. Finally, we highlight a growing need for detecting adaptations that did not follow the classical sweep model and for incorporating new sources of genetic evidence such as information from ancient DNA. Copyright © 2014 Elsevier Ltd. All rights reserved.
Variable Use of Disaccharidase Assays When Evaluating Abdominal Pain
Oloyede, Hannah
2018-01-01
Background and Aims: Patients with a disaccharidase deficiency typically present with abdominal discomfort and often with diarrhea. However, disaccharidase deficiency is often overlooked as a cause of these complaints. Therefore, we sought to determine the prevalence of lactase and sucrase deficiencies in a pediatric population undergoing diagnostic esophagogastroduodenoscopy (EGD) and to describe disaccharidase testing practices among pediatric gastroenterologists. Methods: Endoscopic records from patients undergoing diagnostic EGD and disaccharidase analysis (DA) were retrospectively reviewed. Diagnostic EGDs performed over a 5-year period (2010 through 2014) at a freestanding endoscopy center serving 13 pediatric gastroenterologists were assessed. Demographic and clinical data on patients were collected and grouped; patients with primary sucrase-isomaltase deficiency (SID) were the main focus. The data were stratified by the physician performing the procedures. Results: Over the 5-year study period, 5368 EGDs were performed, with abdominal pain as the primary indication in 3235 cases (60.2%). DAs were performed on 963 patients (17.9% of the total cohort; 29.8% of those with abdominal pain). Lactase deficiencies, sucrase deficiencies, and primary SID were found in 44.7%, 7.6%, and 3.5% of DAs, respectively. The number of DAs performed varied widely among physicians, ranging from 1.6% to 64.5% of EGDs evaluating patients with abdominal pain. Univariate regression analysis revealed significant correlations between the number of DAs performed and the number of SID and lactase deficiencies found (P<.001 for both). Conclusion: Rates of DAs vary widely among pediatric gastroenterologists performing diagnostic EGDs in children with abdominal pain. Physician education and clinical practice guidelines regarding the use of DAs are warranted. PMID:29491758
Schenk, Thomas; Enders, Martin; Pollak, Stefan; Hahn, Ralph; Huzly, Daniela
2009-01-01
Human parvovirus B19 has been linked to a variety of cardiac diseases, as well as to erythema infectiosum, acute arthropathy, and fetal hydrops. A causal association between viral infection and cardiac disease was frequently postulated following the detection of B19 DNA by PCR in endomyocardial biopsy specimens. Since the lifelong persistence of B19 DNA in bone marrow, skin, synovia, tonsils, and liver was previously reported, the aim of our study was to investigate the possibility of asymptomatic B19 DNA persistence in heart tissue. Myocardial autopsy and postmortem blood samples were prospectively collected from 69 bodies sent to the Department of Forensic Medicine, Freiburg University Medical Center, for inquests. All study subjects were screened for B19-specific antibodies using a commercial enzyme immunoassay. Tissue samples were analyzed by real-time PCR for the presence of viral DNA. Since the presence of B19 genotype 2, known to have been circulating before 1960, would prove long-lasting persistence, the presence of the B19 genotype was retrospectively determined in seven of the study subjects by melting temperature analysis and sequencing of the PCR product. B19 DNA was found in myocardial samples from 46 of 48 seropositive and in none of 21 seronegative individuals. B19 genotype 1 was found in three patients born between 1950 and 1969. Genotype 2 was found in four patients born between 1927 and 1957. Our findings suggest lifelong persistence of B19 DNA in heart tissue. Thus, the detection of B19 DNA in myocardial biopsy specimens alone is not sufficient to postulate a relationship between B19 infection and cardiac disease. PMID:19005147
What People with Lactose Intolerance Need to Know about Osteoporosis
... intestine. Lactase is necessary to digest lactose—the natural sugar found in milk and other dairy products. In the intestines, undigested lactose leads to the buildup of gas. Within 30 minutes to 2 hours after eating ...
Genetics Home Reference: lactose intolerance
... or Free article on PubMed Central Järvelä IE. Molecular genetics of adult-type hypolactasia. Ann Med. 2005;37( ... Citation on PubMed Robayo-Torres CC, Nichols BL. Molecular differentiation of congenital lactase ... Bulletins Genetics Home Reference Celebrates Its ...
The effect of SLCO1B1 polymorphism on repaglinide pharmacokinetics persists over a wide dose range.
Kalliokoski, Annikka; Neuvonen, Mikko; Neuvonen, Pertti J; Niemi, Mikko
2008-12-01
To establish whether the effect of SLCO1B1[encoding organic anion transporting polypeptide 1B1 (OATP1B1)] c.521T-->C (p.Val174Ala) polymorphism on the pharmacokinetics of repaglinide is dose-dependent. Twelve healthy volunteers with the SLCO1B1 c.521TT genotype (controls) and eight with the c.521CC genotype ingested a single 0.25-, 0.5-, 1- or 2-mg dose of repaglinide in a dose-escalation study with a wash-out period of > or =1 week. The mean area under the plasma concentration-time curve from time 0 to infinity (AUC(0-infinity)) of 0.25, 0.5, 1 or 2 mg repaglinide was 82% (95% confidence interval 47, 125), 72% (24, 138), 56% (24, 95) or 108% (59, 171) (P < or = 0.001) larger in participants with the SLCO1B1 c.521CC genotype than in those with the c.521TT genotype, respectively. Repaglinide peak plasma concentration and AUC(0-infinity) increased linearly along with repaglinide dose in both genotype groups (r > 0.88, P < 0.001). There was a tendency towards lower blood glucose concentrations after repaglinide administration in the participants with the c.521CC genotype than in those with the c.521TT genotype. The effect of SLCO1B1 c.521T-->C polymorphism on the pharmacokinetics of repaglinide persists throughout the clinically relevant dose range.
Kelly, Sean; Li, Jonathan Z.; Harrigan, P. Richard; Taiwo, Babafemi
2014-01-01
A goal of HIV therapy is to sustain suppression of the plasma viral load below the detection limits of clinical assays. However, widely followed treatment guidelines diverge in their interpretation and recommended management of persistent viremia of low magnitude, reflecting the limited evidence base for this common clinical finding. Here, we review the incidence, risk factors, and potential consequences of low-level HIV viremia (LLV; defined in this review as a viremia level of 50 to 500 copies/ml) and very-low-level viremia (VLLV; defined as a viremia level of <50 copies/ml detected by clinical assays that have quantification cutoffs of <50 copies/ml). Using this framework, we discuss practical issues related to the diagnosis and management of patients experiencing persistent LLV and VLLV. Compared to viral suppression at <50 or 40 copies/ml, persistent LLV is associated with increased risk of antiretroviral drug resistance and overt virologic failure. Higher immune activation and HIV transmission may be additional undesirable consequences in this population. It is uncertain whether LLV of <200 copies/ml confers independent risks, as this level of viremia may reflect assay-dependent artifacts or biologically meaningful events during suppression. Resistance genotyping should be considered in patients with persistent LLV when feasible, and treatment should be modified if resistance is detected. There is a dearth of clinical evidence to guide management when genotyping is not feasible. Increased availability of genotypic assays for samples with viral loads of <400 copies/ml is needed. PMID:24733471
Incorporating evolutionary processes into population viability models.
Pierson, Jennifer C; Beissinger, Steven R; Bragg, Jason G; Coates, David J; Oostermeijer, J Gerard B; Sunnucks, Paul; Schumaker, Nathan H; Trotter, Meredith V; Young, Andrew G
2015-06-01
We examined how ecological and evolutionary (eco-evo) processes in population dynamics could be better integrated into population viability analysis (PVA). Complementary advances in computation and population genomics can be combined into an eco-evo PVA to offer powerful new approaches to understand the influence of evolutionary processes on population persistence. We developed the mechanistic basis of an eco-evo PVA using individual-based models with individual-level genotype tracking and dynamic genotype-phenotype mapping to model emergent population-level effects, such as local adaptation and genetic rescue. We then outline how genomics can allow or improve parameter estimation for PVA models by providing genotypic information at large numbers of loci for neutral and functional genome regions. As climate change and other threatening processes increase in rate and scale, eco-evo PVAs will become essential research tools to evaluate the effects of adaptive potential, evolutionary rescue, and locally adapted traits on persistence. © 2014 Society for Conservation Biology.
French, Bryan Wade; Hammack, Leslie; Tallamy, Douglas W.
2015-01-01
Insect resistance to population control methodologies is a widespread problem. The development of effective resistance management programs is often dependent on detailed knowledge regarding the biology of individual species and changes in that biology associated with resistance evolution. This study examined the reproductive behavior and biology of western corn rootworm beetles of known body size from lines resistant and susceptible to the Cry3Bb1 protein toxin expressed in transgenic Bacillus thuringiensis maize. In crosses between, and within, the resistant and susceptible genotypes, no differences occurred in mating frequency, copulation duration, courtship duration, or fertility; however, females mated with resistant males showed reduced longevity. Body size did not vary with genotype. Larger males and females were not more likely to mate than smaller males and females, but larger females laid more eggs. Moderately strong, positive correlation occurred between the body sizes of successfully mated males and females; however, weak correlation also existed for pairs that did not mate. Our study provided only limited evidence for fitness costs associated with the Cry3Bb1-resistant genotype that might reduce the persistence in populations of the resistant genotype but provided additional evidence for size-based, assortative mating, which could favor the persistence of resistant genotypes affecting body size. PMID:26569315
LaMere, Brandon J.; Kornegay, Janet; Fetterman, Barbara; Sadorra, Mark; Shieh, Jen; Castle, Philip E.
2009-01-01
Human papillomavirus (HPV) genotyping could be clinically useful, depending on the results of large, prospective studies like the HPV Persistence and Progression cohort. The cohort is based on genotyping and follow-up of Hybrid Capture-positive women at Kaiser Permanente, Northern California. HPV DNA testing by Hybrid Capture 2 requires denaturation with alkali, possibly damaging the DNA for optimal PCR-based genotyping. A feasibility study was conducted on paired aliquots of anonymized specimens from 100 women with low-grade intraepithelial lesion cytology. Test aliquots were left in denaturant for 10 or 18 hours at 4°C and then neutralized; comparison aliquots were not denatured but diluted to match the timing, temperature, concentration and salt conditions of the treated specimens. The masked aliquots were tested using a commercialized PCR-based assay that detects of 37 HPV genotypes. There was no overall effect of treatment on test positivity or number of types. HPV16 was marginally more likely to be detected in untreated versus treated aliquots (P = 0.09) but HPV45 was marginally more likely to be detected in treated than untreated aliquots (P = 0.07), suggesting that these differences represented chance (intra-test variability). It can be concluded that residual Hybrid Capture-positive specimens can be accurately genotyped by PCR after Hybrid Capture 2 processing. PMID:17673302
Kim, Yee Suk; Lee, Sungin; Zong, Nansu; Kahng, Jimin
2017-01-01
The present study aimed to investigate differences in prognosis based on human papillomavirus (HPV) infection, persistent infection and genotype variations for patients exhibiting atypical squamous cells of undetermined significance (ASCUS) in their initial Papanicolaou (PAP) test results. A latent Dirichlet allocation (LDA)-based tool was developed that may offer a facilitated means of communication to be employed during patient-doctor consultations. The present study assessed 491 patients (139 HPV-positive and 352 HPV-negative cases) with a PAP test result of ASCUS with a follow-up period ≥2 years. Patients underwent PAP and HPV DNA chip tests between January 2006 and January 2009. The HPV-positive subjects were followed up with at least 2 instances of PAP and HPV DNA chip tests. The most common genotypes observed were HPV-16 (25.9%, 36/139), HPV-52 (14.4%, 20/139), HPV-58 (13.7%, 19/139), HPV-56 (11.5%, 16/139), HPV-51 (9.4%, 13/139) and HPV-18 (8.6%, 12/139). A total of 33.3% (12/36) patients positive for HPV-16 had cervical intraepithelial neoplasia (CIN)2 or a worse result, which was significantly higher than the prevalence of CIN2 of 1.8% (8/455) in patients negative for HPV-16 (P<0.001), while no significant association was identified for other genotypes in terms of genotype and clinical progress. There was a significant association between clearance and good prognosis (P<0.001). Persistent infection was higher in patients aged ≥51 years (38.7%) than in those aged ≤50 years (20.4%; P=0.036). Progression from persistent infection to CIN2 or worse (19/34, 55.9%) was higher than clearance (0/105, 0.0%; P<0.001). In the LDA analysis, using symmetric Dirichlet priors α=0.1 and β=0.01, and clusters (k)=5 or 10 provided the most meaningful groupings. Statistical and LDA analyses produced consistent results regarding the association between persistent infection of HPV-16, old age and long infection period with a clinical progression of CIN2 or worse. Therefore, LDA results may be presented as explanatory evidence during time-constrained patient-doctor consultations in order to deliver information regarding the patient's status. PMID:28587376
ERIC Educational Resources Information Center
Wickrama, K. A. S.; O'Neal, Catherine Walker
2013-01-01
Previous research has mainly focused on the persistent direct influence of early life contexts on young adult socioeconomic attainment, and less is known about intraindividual processes that are responsible for this persistent influence. The present study, using genetically informed longitudinal, prospective data from a nationally representative…
Koplin, Jennifer J; Suaini, Noor H A; Vuillermin, Peter; Ellis, Justine A; Panjari, Mary; Ponsonby, Anne-Louise; Peters, Rachel L; Matheson, Melanie C; Martino, David; Dang, Thanh; Osborne, Nicholas J; Martin, Pamela; Lowe, Adrian; Gurrin, Lyle C; Tang, Mimi L K; Wake, Melissa; Dwyer, Terry; Hopper, John; Dharmage, Shyamali C; Allen, Katrina J
2016-02-01
There is evolving evidence that vitamin D insufficiency may contribute to food allergy, but findings vary between populations. Lower vitamin D-binding protein (DBP) levels increase the biological availability of serum vitamin D. Genetic polymorphisms explain almost 80% of the variation in binding protein levels. We sought to investigate whether polymorphisms that lower the DBP could compensate for adverse effects of low serum vitamin D on food allergy risk. From a population-based cohort study (n = 5276) we investigated the association between serum 25-hydroxyvitamin D3 (25[OH]D3) levels and food allergy at age 1 year (338 challenge-proven food-allergic and 269 control participants) and age 2 years (55 participants with persistent and 50 participants with resolved food allergy). 25(OH)D3 levels were measured using liquid chromatography-tandem mass spectrometry and adjusted for season of blood draw. Analyses were stratified by genotype at rs7041 as a proxy marker of DBP levels (low, the GT/TT genotype; high, the GG genotype). Low serum 25(OH)D3 level (≤50 nM/L) at age 1 years was associated with food allergy, particularly among infants with the GG genotype (odds ratio [OR], 6.0; 95% CI, 0.9-38.9) but not in those with GT/TT genotypes (OR, 0.7; 95% CI, 0.2-2.0; P interaction = .014). Maternal antenatal vitamin D supplementation was associated with less food allergy, particularly in infants with the GT/TT genotype (OR, 0.10; 95% CI, 0.03-0.41). Persistent vitamin D insufficiency increased the likelihood of persistent food allergy (OR, 12.6; 95% CI, 1.5-106.6), particularly in those with the GG genotype. Polymorphisms associated with lower DBP level attenuated the association between low serum 25(OH)D3 level and food allergy, consistent with greater vitamin D bioavailability in those with a lower DBP level. This increases the biological plausibility of a role for vitamin D in the development of food allergy. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Spread of Chikungunya Virus East/Central/South African Genotype in Northeast Brazil.
Charlys da Costa, Antonio; Thézé, Julien; Komninakis, Shirley Cavalcante Vasconcelos; Sanz-Duro, Rodrigo Lopes; Felinto, Marta Rejane Lemos; Moura, Lúcia Cristina Corrêa; Barroso, Ivoneide Moreira de Oliveira; Santos, Lucineide Eliziario Correia; Nunes, Mardjane Alves de Lemos; Moura, Adriana Avila; Lourenço, José; Deng, Xutao; Delwart, Eric L; Guimarães, Maria Raquel Dos Anjos Silva; Pybus, Oliver G; Sabino, Ester C; Faria, Nuno R
2017-10-01
We investigated an outbreak of exanthematous illness in Maceió by using molecular surveillance; 76% of samples tested positive for chikungunya virus. Genetic analysis of 23 newly generated genomes identified the East/Central/South African genotype, suggesting that this lineage has persisted since mid-2014 in Brazil and may spread in the Americas and beyond.
Dragović, Tamara; Ajdinović, Boris; Hrvacević, Rajko; Ilić, Vesna; Magić, Zvonko; Andelković, Zoran; Kocev, Nikola
2010-04-01
Diabetic nephropathy (DN) is a clinical syndrome characterized by persistent albuminuria, increasing arterial blood pressure and progressive decline in glomerular filtration rate (GFR). When persistent albuminuria is established, antihypertensive treatment becomes most important factor in slowing the progression of diabetic glomerulopathy. The aim of this study was to examine if renoprotective response to a short-term losartan therapy depends on 1166 A/C gene polymorphism for its target receptor. The study included 35 patients with diabetes mellitus type 1 and persistently high urinary albumin excretion rate (UAE: > 30 mg/24 h), genotyped for the 1166 A/C gene polymorphism for the angiotensin II type 1 receptor (AT1R). The participants were segregated into 3 genotype groups according to combinations of A or C allele: AA (16%), AC (15%) and CC (11%). The patients received losartan 50 mg daily for 4 weeks, following 100 mg daily for another 8 weeks. At baseline and after 12 weeks of the treatment period UAE, blood pressure, GFR and filtration fraction (FF) were determined. After 12 weeks of the treatment with losartan, albuminuria was reduced from baseline by 9% [95% confidence interval (CI): 1-17, p = 0.039] in the AA genotype, and by 11% (95% CI: 6-17, p = 0.0001) in the AC genotype. Losartan treatment reduced albuminuria in the CC group by 5% (95% CI: -13-22, p = 0.47). Glomerular filtration rate remained unchanged in all genotype groups. Filtration fraction was significantly reduced from baseline by 0.018 +/- 0.024 (p = 0.012) only in the AC genotype. In the AA genotype, FF was reduced from baseline by 0.017 +/- 0.03 (p = 0.052), and in the CC genotype by 0.01 +/- 0.008 (p = 0.092). In the AA group, systolic blood pressure declined from 136 +/- 24 mmHg at baseline, to an average of 121 +/- 18 mmHg at the end of the study (p = 0.001). The AC group achived reduction from 131 +/- 10 mmHg at baseline to 115 +/- 7 mmHg (p = 0.001) during the investigation period. In the AA genotype group losartan reduced diastolic blood pressure from 86 +/- 13 mmHg at baseline to 78 +/- 8 mmHg (p = 0.004), and in the AC genotype from 88 +/- 5 mmHg at baseline to 11.7 +/- 5.6 mmHg during the investigation period (p = 0.001). In the CC genotype diastolic blood pressure reduction remained nonsignificant (p = 0.066). The results of our small sample size study provide the evidence that 1166 A/C AT1R polymorphism could be associated with the renoprotective response to losartan therapy.
Martini, M C; Smith, D E; Savaiano, D A
1987-10-01
Lactose digestion from and tolerance to flavored and frozen yogurts, ice cream, and ice milk were evaluated (20 g lactose/meal) in lactase-deficient subjects by use of breath hydrogen techniques. Unflavored yogurt caused significantly less hydrogen production than milk (37 vs 185 delta ppm X h, n = 9). Flavored yogurt was intermediate (77 delta ppm X h). Subjects were free of symptoms after consuming flavored and unflavored yogurts. Of seven commercial yogurts tested, all contained significant levels of microbial beta-galactosidase (beta-gal). In addition, eight subjects were fed meals of milk, ice milk, ice cream, and frozen yogurts with and without cultures containing high levels of beta-gal. Peak hydrogen excretion after consumption of frozen yogurt with high beta-gal was less than one-half of that observed after the other five test meals and intolerance symptoms were absent. Tolerance to frozen yogurt, produced under usual commercial procedures, was found to be similar to that of ice milk and ice cream.
Study of enzyme activities in the descending part of the duodenum in patients of duodenal ulcer.
Fernandes, V L C; Bhasin, D K; Rana, S V
2006-03-01
The aim of this study was to measure the levels of lactase, sucrase, maltase, leucine amino peptidase and gamma-glutamyl transpeptidase in duodenum of Indian patients with duodenal ulcer. The effect of duodenum inflammation on these brush border enzymes has also been analysed in this study. Levels of lactase, sucrase, maltase, leucine amino peptidase and gamma-glutamyl transpeptidase were assessed in duodenal biopsies of 20 patients of duodenal ulcer and 20 non-ulcer dyspepsia. The duodenal biopsy specimens were also examined histopathologically for presence or absence of inflammation. There was no significant difference (p>0.05) in the activity of above mentioned enzyme levels in both the groups. Only levels of gamma-glutamyl transpeptidase were significantly decreased in patients of duodenal ulcer with duodenal inflammation. This study shows that only the levels of gamma-glutamyl transpeptidase were significantly decreased in patients of duodenal ulcer with inflammation but no change in duodenal enzymes due to duodenal ulcer as compared to non-ulcer dyspepsia.
NASA Astrophysics Data System (ADS)
Pope, Sandi R.; Tolleson, Tonya D.; Williams, R. Jill; Underhill, Russell D.; Deal, S. Todd
1998-06-01
At Georgia Southern University, we offer a sophomore-level introductory biochemistry course that is aimed at nutrition and chemistry education majors. The laboratory portion of this course has long lacked an experimental introduction to enzymes. We have developed a simple enzyme assay utilizing lactase enzyme from crushed LactAid tablets and a 5% lactose solution ("synthetic milk"). In the experiment, the students assay the activity of the enzyme on the "synthetic milk" at pHs of approximately 1, 6, and 8 with the stated goal of determining where lactose functions in the digestive tract. The activity of the lactase may be followed chromatographically or spectrophotometrically. The experiment, which is actually a simple pH assay, is easily implemented in allied health chemistry laboratory courses and readily lends itself to adaptation for more complex kinetic assays in upper-level biochemistry laboratory courses. The experimental details, including a list of required supplies and hints for implementation, are provided.
A whole-plant screening test to identify genotypes with superior freezing tolerance.
Bertrand, Annick; Castonguay, Yves; Bourassa, Josée
2014-01-01
Freezing tolerance is a determinant factor of persistence of perennials grown in northern climate. Selection for winterhardiness in field nurseries is difficult because of the unpredictability of occurrence of test winters allowing the identification of hardy genotypes. Here we describe a whole-plant assay entirely performed indoor in growth chambers and walk-in freezers to identify genotypes with superior tolerance to freezing within populations of open pollinated species. Three successive freezing stresses are applied to progressively eliminate 90 % of the population and to retain only the 10 % best performing genotypes. This approach can be used to generate recurrently selected populations more tolerant to freezing in different species.
Vriend, Henrike J; Bogaards, Johannes A; van Bergen, Jan E A M; Brink, Antoinette A T P; van den Broek, Ingrid V F; Hoebe, Christian J P A; King, Audrey J; van der Sande, Marianne A B; Wolffs, Petra F G; de Melker, Hester E
2015-01-01
We assessed whether infection with chlamydia increases the incidence of carcinogenic human papillomavirus (HPV) infections and if HPV persistence is affected by chlamydia co-infection. For 1982 women (16–29 years-old) participating in two consecutive rounds of a chlamydia screening implementation trial, swabs were polymerase chain reaction tested to detect chlamydia and 14 carcinogenic HPV genotypes. HPV type-specific incidence and persistence rates were stratified for chlamydia positivity at follow-up. Associations were assessed by multilevel logistic regression analyses with correction for sexual risk factors. HPV type-specific incidence ranged from 1.4% to 8.9% and persistence from 22.7% to 59.4% after a median follow-up of 11 months (interquartile range: 11–12). Differences in 1-year HPV persistence rates between chlamydia -infected and noninfected women were less distinct than differences in HPV incidence rates (pooled adjusted odds ratios of 1.17 [95% CI: 0.69–1.96] and 1.84 [95% CI: 1.36–2.47], respectively). The effect of chlamydia co-infection on HPV-infection risk did not significantly differ by HPV genotype. In conclusion, infection with chlamydia increases the risk of infection by carcinogenic HPV types and may enhance persistence of some HPV types. Although these findings could reflect residual confounding through unobserved risk factors, our results do give reason to explore more fully the association between chlamydia and HPV type-specific acquisition and persistence. PMID:26194784
Long-term persistence of primary genotypic resistance after HIV-1 seroconversion.
Pao, David; Andrady, Ushan; Clarke, Janette; Dean, Gillian; Drake, Susan; Fisher, Martin; Green, Tanya; Kumar, Siva; Murphy, Maurice; Tang, Alan; Taylor, Stephen; White, David; Underhill, Gillian; Pillay, Deenan; Cane, Patricia
2004-12-15
Primary infection with drug-resistant HIV-1 is well documented. We have followed up patients infected with such viruses to determine the stability of resistance-associated mutations. Fourteen patients who experienced primary infection with genotypic evidence of resistance were followed for up to 3 years. Drug resistance-associated mutations persisted over time in most patients studied. In particular, M41L, T69N, K103N, and T215 variants within reverse transcriptase (RT) and multidrug resistance demonstrated little reversion to wild-type virus. By contrast, Y181C and K219Q in RT, occurring alone, disappeared within 25 and 9 months, respectively. Multidrug resistance in 2 patients was found to be stable for up to 18 months, the maximum period studied. We conclude that certain resistance-associated mutations are highly stable and these data support the recommendation that all new HIV diagnoses in areas where primary resistance may occur should undergo genotyping irrespective of whether the date of seroconversion is known.
Robinson, John D; Wares, John P; Drake, John M
2013-01-01
Extinction is ubiquitous in natural systems and the ultimate fate of all biological populations. However, the factors that contribute to population extinction are still poorly understood, particularly genetic diversity and composition. A laboratory experiment was conducted to examine the influences of environmental variation and genotype diversity on persistence in experimental Daphnia magna populations. Populations were initiated in two blocks with one, two, three, or six randomly selected and equally represented genotypes, fed and checked for extinction daily, and censused twice weekly over a period of 170 days. Our results show no evidence for an effect of the number of genotypes in a population on extinction hazard. Environmental variation had a strong effect on hazards in both experimental blocks, but the direction of the effect differed between blocks. In the first block, variable environments hastened extinction, while in the second block, hazards were reduced under variable food input. This occurred despite greater fluctuations in population size in variable environments in the second block of our experiment. Our results conflict with previous studies, where environmental variation consistently increased extinction risk. They are also at odds with previous studies in other systems that documented significant effects of genetic diversity on population persistence. We speculate that the lack of sexual reproduction, or the phenotypic similarity among our experimental lines, might underlie the lack of a significant effect of genotype diversity in our study. PMID:23467276
Direct evidence of milk consumption from ancient human dental calculus.
Warinner, C; Hendy, J; Speller, C; Cappellini, E; Fischer, R; Trachsel, C; Arneborg, J; Lynnerup, N; Craig, O E; Swallow, D M; Fotakis, A; Christensen, R J; Olsen, J V; Liebert, A; Montalva, N; Fiddyment, S; Charlton, S; Mackie, M; Canci, A; Bouwman, A; Rühli, F; Gilbert, M T P; Collins, M J
2014-11-27
Milk is a major food of global economic importance, and its consumption is regarded as a classic example of gene-culture evolution. Humans have exploited animal milk as a food resource for at least 8500 years, but the origins, spread, and scale of dairying remain poorly understood. Indirect lines of evidence, such as lipid isotopic ratios of pottery residues, faunal mortality profiles, and lactase persistence allele frequencies, provide a partial picture of this process; however, in order to understand how, where, and when humans consumed milk products, it is necessary to link evidence of consumption directly to individuals and their dairy livestock. Here we report the first direct evidence of milk consumption, the whey protein β-lactoglobulin (BLG), preserved in human dental calculus from the Bronze Age (ca. 3000 BCE) to the present day. Using protein tandem mass spectrometry, we demonstrate that BLG is a species-specific biomarker of dairy consumption, and we identify individuals consuming cattle, sheep, and goat milk products in the archaeological record. We then apply this method to human dental calculus from Greenland's medieval Norse colonies, and report a decline of this biomarker leading up to the abandonment of the Norse Greenland colonies in the 15(th) century CE.
Direct evidence of milk consumption from ancient human dental calculus
Warinner, C.; Hendy, J.; Speller, C.; Cappellini, E.; Fischer, R.; Trachsel, C.; Arneborg, J.; Lynnerup, N.; Craig, O. E.; Swallow, D. M.; Fotakis, A.; Christensen, R. J.; Olsen, J. V.; Liebert, A.; Montalva, N.; Fiddyment, S.; Charlton, S.; Mackie, M.; Canci, A.; Bouwman, A.; Rühli, F.; Gilbert, M. T. P.; Collins, M. J.
2014-01-01
Milk is a major food of global economic importance, and its consumption is regarded as a classic example of gene-culture evolution. Humans have exploited animal milk as a food resource for at least 8500 years, but the origins, spread, and scale of dairying remain poorly understood. Indirect lines of evidence, such as lipid isotopic ratios of pottery residues, faunal mortality profiles, and lactase persistence allele frequencies, provide a partial picture of this process; however, in order to understand how, where, and when humans consumed milk products, it is necessary to link evidence of consumption directly to individuals and their dairy livestock. Here we report the first direct evidence of milk consumption, the whey protein β-lactoglobulin (BLG), preserved in human dental calculus from the Bronze Age (ca. 3000 BCE) to the present day. Using protein tandem mass spectrometry, we demonstrate that BLG is a species-specific biomarker of dairy consumption, and we identify individuals consuming cattle, sheep, and goat milk products in the archaeological record. We then apply this method to human dental calculus from Greenland's medieval Norse colonies, and report a decline of this biomarker leading up to the abandonment of the Norse Greenland colonies in the 15th century CE. PMID:25429530
Giurgea, Georgiana-Aura; Brunner-Ziegler, Sophie; Jilma, Bernd; Sunder-Plassmann, Raute; Koppensteiner, Renate; Gremmel, Thomas
2017-05-01
A recent study suggested that the plasminogen activator inhibitor (PAI)-1 4G/5G genotype may play a role in the resolution of deep vein thrombosis (DVT) after surgery. In the present study, we investigated the association between PAI-1 4G/5G genotype and the persistence of venous occlusion after acute idiopathic DVT of the lower limb. The PAI-1 4G/5G genotype was determined by real-Time PCR in 43 patients with unprovoked DVT of the lower limb. Residual venous occlusion was assessed by duplex sonography 1, 3, 6, 12 and 24months after the acute event. The PAI-1 Activity was determined by ELISA. Ten patients (23%) were homozygous for 4G (4G/4G), 27 patients (63%) were heterozygous 4G/5G and 6 patients (14%) were homozygous for 5G (5G/5G). Residual venous occlusion (RVO) was found in 77%, 65%, 58%, 56% and 37% of the overall study population, at 1, 3, 6, 12 and 24months after acute DVT, respectively. The presence of residual venous occlusion at 1, 3, 6, 12 and 24months after acute unprovoked DVT did not differ significantly between genotypes, but age was associated with RVO. Plasma levels of PAI-1 activity correlated with body mass index but was not associated with genotypes in our study. The PAI-1 4G/5G genotype was not a relevant predictor of persistent residual venous occlusion after idiopathic DVT, which however was associated with age. Copyright © 2017 Elsevier Ltd. All rights reserved.
Hepatitis C Virus: Viral Quasispecies and Genotypes.
Tsukiyama-Kohara, Kyoko; Kohara, Michinori
2017-12-22
Hepatitis C virus (HCV) mainly replicates in the cytoplasm, where it easily establishes persistent infection, resulting in chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Due to its high rate of mutation, HCV forms viral quasispecies, categorized based on the highly variable regions in the envelope protein and nonstructural 5A protein. HCV possesses seven major genotypes, among which genotype 1 is the most prevalent globally. The distribution of HCV genotypes varies based on geography, and each genotype has a different sensitivity to interferon treatment. Recently-developed direct-acting antivirals (DAAs), which target viral proteases or polymerases, mediate drastically better antiviral effects than previous therapeutics. Although treatment with DAAs has led to the development of drug-resistant HCV mutants, the most recently approved DAAs show improved pan-genomic activity, with a higher barrier to viral resistance.
Winkel, Anders; Pedersen, Ole; Ella, Evangelina; Ismail, Abdelbagi M.; Colmer, Timothy D.
2014-01-01
Floods can completely submerge some rice (Oryza sativa L.) fields. Leaves of rice have gas films that aid O2 and CO2 exchange under water. The present study explored the relationship between gas film persistence and underwater net photosynthesis (PN) as influenced by genotype and submergence duration. Four contrasting genotypes (FR13A, IR42, Swarna, and Swarna-Sub1) were submerged for 13 days in the field and leaf gas films, chlorophyll, and the capacity for underwater PN at near ambient and high CO2 were assessed with time of submergence. At high CO2 during the PN assay, all genotypes initially showed high rates of underwater PN, and this rate was not affected by time of submergence in FR13A. This superior photosynthetic performance of FR13A was not evident in Swarna-Sub1 (carrying the SUB1 QTL) and the declines in underwater PN in both Swarna-Sub1 and Swarna were equal to that in IR42. At near ambient CO2 concentration, underwater PN declined in all four genotypes and this corresponded with loss of leaf gas films with time of submergence. FR13A retained leaf gas films moderately longer than the other genotypes, but gas film retention was not linked to SUB1. Diverse rice germplasm should be screened for gas film persistence during submergence, as this trait could potentially increase carbohydrate status and internal aeration owing to increased underwater PN, which contributes to submergence tolerance in rice. PMID:24759881
Winkel, Anders; Pedersen, Ole; Ella, Evangelina; Ismail, Abdelbagi M; Colmer, Timothy D
2014-07-01
Floods can completely submerge some rice (Oryza sativa L.) fields. Leaves of rice have gas films that aid O2 and CO2 exchange under water. The present study explored the relationship between gas film persistence and underwater net photosynthesis (PN) as influenced by genotype and submergence duration. Four contrasting genotypes (FR13A, IR42, Swarna, and Swarna-Sub1) were submerged for 13 days in the field and leaf gas films, chlorophyll, and the capacity for underwater PN at near ambient and high CO2 were assessed with time of submergence. At high CO2 during the PN assay, all genotypes initially showed high rates of underwater PN, and this rate was not affected by time of submergence in FR13A. This superior photosynthetic performance of FR13A was not evident in Swarna-Sub1 (carrying the SUB1 QTL) and the declines in underwater PN in both Swarna-Sub1 and Swarna were equal to that in IR42. At near ambient CO2 concentration, underwater PN declined in all four genotypes and this corresponded with loss of leaf gas films with time of submergence. FR13A retained leaf gas films moderately longer than the other genotypes, but gas film retention was not linked to SUB1. Diverse rice germplasm should be screened for gas film persistence during submergence, as this trait could potentially increase carbohydrate status and internal aeration owing to increased underwater PN, which contributes to submergence tolerance in rice. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.
The effect of SLCO1B1 polymorphism on repaglinide pharmacokinetics persists over a wide dose range
Kalliokoski, Annikka; Neuvonen, Mikko; Neuvonen, Pertti J; Niemi, Mikko
2008-01-01
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECTOrganic anion transporting polypeptide 1B1 is an influx transporter expressed on the basolateral membrane of hepatocytes.A common single nucleotide polymorphism, c.521T→C (p.Val174Ala), of the SLCO1B1 gene has been associated with increased plasma repaglinide concentrations in healthy volunteers.Previous studies at low repaglinide doses have suggested that the effect of SLCO1B1 c.521T→C polymorphism on the pharmacokinetics of repaglinide could be dose-dependent. WHAT THIS STUDY ADDSRepaglinide peak plasma concentration and area under the plasma concentration–time curve increased linearly along with repaglinide dose ranging from 0.25 to 2 mg in both the predominant c.521TT and rare c.521CC genotype group.The effect of SLCO1B1 c.521T→C polymorphism on repaglinide pharmacokinetics persists over a wide dose range. AIMS To establish whether the effect of SLCO1B1[encoding organic anion transporting polypeptide 1B1 (OATP1B1)] c.521T→C (p.Val174Ala) polymorphism on the pharmacokinetics of repaglinide is dose-dependent. METHODS Twelve healthy volunteers with the SLCO1B1 c.521TT genotype (controls) and eight with the c.521CC genotype ingested a single 0.25-, 0.5-, 1- or 2-mg dose of repaglinide in a dose-escalation study with a wash-out period of ≥1 week. RESULTS The mean area under the plasma concentration–time curve from time 0 to infinity (AUC0–∞) of 0.25, 0.5, 1 or 2 mg repaglinide was 82% (95% confidence interval 47, 125), 72% (24, 138), 56% (24, 95) or 108% (59, 171) (P ≤ 0.001) larger in participants with the SLCO1B1 c.521CC genotype than in those with the c.521TT genotype, respectively. Repaglinide peak plasma concentration and AUC0–∞ increased linearly along with repaglinide dose in both genotype groups (r > 0.88, P < 0.001). There was a tendency towards lower blood glucose concentrations after repaglinide administration in the participants with the c.521CC genotype than in those with the c.521TT genotype. CONCLUSIONS The effect of SLCO1B1 c.521T→C polymorphism on the pharmacokinetics of repaglinide persists throughout the clinically relevant dose range. PMID:18823304
Chen, Ming-liang; Wang, Gang-yi; Chen, Min; Zhou, Hai-jian; Shao, Zhu-jun; Zhang, Xi; Wu, Fan
2010-07-01
To investigate the genotypic characteristics and persistence of Legionella pulsed-field gel electrophoresis (PFGE) patterns in 16 air-conditioner cooling towers in six different public sites of Shanghai. From May to October, continuous sampling was operated once per month in 2007. Legionella strains isolated from the 16 cooling towers were confirmed by serological and latex agglutination. PFGE was applied for the fingerprinting of the isolates, while the cluster results of PFGE were analyzed by BioNumerics software. 131 strains of Legionella were isolated, including L. pneumophila, L. bozemanae, L. micdadei and L. anisa. 52 distinguishable PFGE patterns were differentiated among the 16 cooling towers, with 37 patterns were owned by just one cooling tower, which was not shared with other cooling towers, while 15 patterns were shared by more than 2 cooling towers. All the cooling towers had ≥ 2 PFGE patterns, while in 13 cooling towers the same PFGE patterns were recovered during the six months. From June to October of 2007, 18 strains of Legionella belonging to the PFGE pattern of LPAs.SH0078 were isolated continuously from 6 cooling towers. This study demonstrated great genotypic diversity and complexity of Legionella in cooling towers. Persistence of the PFGE patterns was observed in 81.25% of the cooling towers. The PFGE pattern of LPAs. SH0078 was distributed widely, suggesting it might be the dominate strain in Shanghai.
Yi, MinKyung; Hu, Fengyu; Joyce, Michael; Saxena, Vikas; Welsch, Christoph; Chavez, Deborah; Guerra, Bernadette; Yamane, Daisuke; Veselenak, Ronald; Pyles, Rick; Walker, Christopher M.; Tyrrell, Lorne; Bourne, Nigel; Lanford, Robert E.
2014-01-01
ABSTRACT Persistent infection is a key feature of hepatitis C virus (HCV). However, chimpanzee infections with cell culture-derived viruses (JFH1 or related chimeric viruses that replicate efficiently in cell culture) have been limited to acute-transient infections with no pathogenicity. Here, we report persistent infection with chronic hepatitis in a chimpanzee challenged with cell culture-derived genotype 1a virus (H77S.2) containing 6 cell culture-adaptive mutations. Following acute-transient infection with a chimeric H77/JFH1 virus (HJ3-5), intravenous (i.v.) challenge with 106 FFU H77S.2 virus resulted in immediate seroconversion and, following an unusual 4- to 6-week delay, persistent viremia accompanied by alanine aminotransferase (ALT) elevation, intrahepatic innate immune responses, and diffuse hepatopathy. This first persistent infection with cell culture-produced HCV provided a unique opportunity to assess evolution of cell culture-adapted virus in vivo. Synonymous and nonsynonymous nucleotide substitution rates were greatest during the first 8 weeks of infection. Of 6 cell culture-adaptive mutations in H77S.2, Q1067R (NS3) had reverted to Q1067 and S2204I (NS5A) was replaced by T2204 within 8 weeks of infection. By 62 weeks, 4 of 6 mutations had reverted to the wild-type sequence, and all reverted to the wild-type sequence by 194 weeks. The data suggest H77S.2 virus has greater potential for persistence and pathogenicity than JFH1 and demonstrate both the capacity of a nonfit virus to persist for weeks in the liver in the absence of detectable viremia as well as strong selective pressure against cell culture-adaptive mutations in vivo. IMPORTANCE This study shows that mutations promoting the production of infectious genotype 1a HCV in cell culture have the opposite effect and attenuate replication in the liver of the only fully permissive animal species other than humans. It provides the only example to date of persistent infection in a chimpanzee challenged with cell culture-produced virus and provides novel insight into the forces shaping molecular evolution of that virus during 5 years of persistent infection. It demonstrates that a poorly fit virus can replicate for weeks within the liver in the absence of detectable viremia, an observation that expands current concepts of HCV pathogenesis and that is relevant to relapses observed with direct-acting antiviral therapies. PMID:24429362
Hepatitis C Virus: Viral Quasispecies and Genotypes
Tsukiyama-Kohara, Kyoko; Kohara, Michinori
2017-01-01
Hepatitis C virus (HCV) mainly replicates in the cytoplasm, where it easily establishes persistent infection, resulting in chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Due to its high rate of mutation, HCV forms viral quasispecies, categorized based on the highly variable regions in the envelope protein and nonstructural 5A protein. HCV possesses seven major genotypes, among which genotype 1 is the most prevalent globally. The distribution of HCV genotypes varies based on geography, and each genotype has a different sensitivity to interferon treatment. Recently-developed direct-acting antivirals (DAAs), which target viral proteases or polymerases, mediate drastically better antiviral effects than previous therapeutics. Although treatment with DAAs has led to the development of drug-resistant HCV mutants, the most recently approved DAAs show improved pan-genomic activity, with a higher barrier to viral resistance. PMID:29271914
Figueiredo, Cristina Adelaide; Luchs, Adriana; Russo, Denise Hage; de Cassia Compagnoli Carmona, Rita; Afonso, Ana Maria Sardinha; de Oliveira, Maria Isabel; Curti, Suely Pires; de Moraes, José Cassio; Toscano, Cristiana M; Ciccone, Flavia Helena; Timenetsky, Maria do Carmo Sampaio Tavares
2014-06-01
The aim of the present study was to identify the rubella virus (RV) and enterovirus (EV) genotypes detected during the Epidemiological Surveillance on Exanthematic Febrile Diseases (VIGIFEX) study and to perform phylogenetic analysis. Ten RV- and four EV-positive oropharyngeal samples isolated from cell culture were subjected to RT-PCR and sequencing. Genotype 1G and echovirus 9 (E-9) was identified in RV- and EV-positive samples, respectively. The RV 1G genotype has been persisting in Brazil since 2000-2001. No evidence of E-9 being involved in exanthematic illness in Brazil has been reported previously. Differential laboratory diagnosis is essential for management of rash and fever disease.
Xia, Wenjing; Nielly-Thibault, Lou; Charron, Guillaume; Landry, Christian R; Kasimer, Dahlia; Anderson, James B; Kohn, Linda M
2017-02-01
Genetic diversity in experimental, domesticated and wild populations of the related yeasts, Saccharomyces cerevisiae and Saccharomyces paradoxus, has been well described at the global scale. We investigated the population genomics of a local population on a small spatial scale to address two main questions. First, is there genomic variation in a S. paradoxus population at a spatial scale spanning centimetres (microsites) to tens of metres? Second, does the distribution of genomic variants persist over time? Our sample consisted of 42 S. paradoxus strains from 2014 and 43 strains from 2015 collected from the same 72 microsites around four host trees (Quercus rubra and Quercus alba) within 1 km 2 in a mixed hardwood forest in southern Ontario. Six additional S. paradoxus strains recovered from adjacent maple and beech trees in 2015 are also included in the sample. Whole-genome sequencing and genomic SNP analysis revealed five differentiated groups (clades) within the sampled area. The signal of persistence of genotypes in their microsites from 2014 to 2015 was highly significant. Isolates from the same tree tended to be more related than strains from different trees, with limited evidence of dispersal between trees. In growth assays, one genotype had a significantly longer lag phase than the other strains. Our results indicate that different clades coexist at fine spatial scale and that population structure persists over at least a one-year interval in these wild yeasts, suggesting the efficacy of yearly sampling to follow longer term genetic dynamics in future studies. © 2016 John Wiley & Sons Ltd.
Echeverry, Diego F; Nair, Shalini; Osorio, Lyda; Menon, Sanjay; Murillo, Claribel; Anderson, Tim J C
2013-01-07
Resistance to chloroquine and antifolate drugs has evolved independently in South America, suggesting that genotype - phenotype studies aimed at understanding the genetic basis of resistance to these and other drugs should be conducted in this continent. This research was conducted to better understand the population structure of Colombian Plasmodium falciparum in preparation for such studies. A set of 384 SNPs were genotyped in blood spot DNA samples from 447 P. falciparum infected subjects collected over a ten year period from four provinces of the Colombian Pacific coast to evaluate clonality, population structure and linkage disequilibrium (LD). Most infections (81%) contained a single predominant clone. These clustered into 136 multilocus genotypes (MLGs), with 32% of MLGs recovered from multiple (2 - 28) independent subjects. We observed extremely low genotypic richness (R = 0.42) and long persistence of MLGs through time (median = 537 days, range = 1 - 2,997 days). There was a high probability (>5%) of sampling parasites from the same MLG in different subjects within 28 days, suggesting caution is needed when using genotyping methods to assess treatment success in clinical drug trials. Panmixia was rejected as four well differentiated subpopulations (FST = 0.084 - 0.279) were identified. These occurred sympatrically but varied in frequency within the four provinces. Linkage disequilibrium (LD) decayed more rapidly (r2 = 0.17 for markers <10 kb apart) than observed previously in South American samples. We conclude that Colombian populations have several advantages for association studies, because multiple clone infections are uncommon and LD decays over the scale of one or a few genes. However, the extensive population structure and low genotype richness will need to be accounted for when designing and analyzing association studies.
2013-01-01
Background Resistance to chloroquine and antifolate drugs has evolved independently in South America, suggesting that genotype - phenotype studies aimed at understanding the genetic basis of resistance to these and other drugs should be conducted in this continent. This research was conducted to better understand the population structure of Colombian Plasmodium falciparum in preparation for such studies. Results A set of 384 SNPs were genotyped in blood spot DNA samples from 447 P. falciparum infected subjects collected over a ten year period from four provinces of the Colombian Pacific coast to evaluate clonality, population structure and linkage disequilibrium (LD). Most infections (81%) contained a single predominant clone. These clustered into 136 multilocus genotypes (MLGs), with 32% of MLGs recovered from multiple (2 – 28) independent subjects. We observed extremely low genotypic richness (R = 0.42) and long persistence of MLGs through time (median = 537 days, range = 1 – 2,997 days). There was a high probability (>5%) of sampling parasites from the same MLG in different subjects within 28 days, suggesting caution is needed when using genotyping methods to assess treatment success in clinical drug trials. Panmixia was rejected as four well differentiated subpopulations (FST = 0.084 - 0.279) were identified. These occurred sympatrically but varied in frequency within the four provinces. Linkage disequilibrium (LD) decayed more rapidly (r2 = 0.17 for markers <10 kb apart) than observed previously in South American samples. Conclusions We conclude that Colombian populations have several advantages for association studies, because multiple clone infections are uncommon and LD decays over the scale of one or a few genes. However, the extensive population structure and low genotype richness will need to be accounted for when designing and analyzing association studies. PMID:23294725
21 CFR 184.1387 - Lactase enzyme preparation from Candida pseudotropicalis.
Code of Federal Regulations, 2010 CFR
2010-04-01
....2.1.23), which converts lactose to glucose and galactose. It is prepared from yeast that has been... defined in § 170.3(o)(9) of this chapter, to convert lactose to glucose and galactose. (2) The ingredient... manufacturing practice is limited to use of this ingredient to reduce the lactose content in milk and milk...
21 CFR 184.1387 - Lactase enzyme preparation from Candida pseudotropicalis.
Code of Federal Regulations, 2011 CFR
2011-04-01
....2.1.23), which converts lactose to glucose and galactose. It is prepared from yeast that has been... defined in § 170.3(o)(9) of this chapter, to convert lactose to glucose and galactose. (2) The ingredient... manufacturing practice is limited to use of this ingredient to reduce the lactose content in milk and milk...
USDA-ARS?s Scientific Manuscript database
Carbohydrate digesting enzyme activities are measured in duodenal biopsies to detect deficiencies of lactase and sucrase activities, however glucoamylase (GA) assays for starch digestion are not included. Because food starch represents half of energy intake in the human diet, assays for starch diges...
HPV-Testing in Follow-up of Patients Treated for CIN2+ Lesions
Mariani, Luciano; Sandri, Maria Teresa; Preti, Mario; Origoni, Massimo; Costa, Silvano; Cristoforoni, Paolo; Bottari, Fabio; Sideri, Mario
2016-01-01
Persistent positivity of HPV-DNA testing is considered a prognostic index of recurrent disease in patients treated for CIN2+. HPV detection, and particularly genotyping, has an adequate high rate of sensitivity and specificity (along with an optimal reproducibility), for accurately predicting treatment failure, allowing for an intensified monitoring activity. Conversely, women with a negative HPV-test 6 months after therapy have a very low risk for residual/recurrent disease, which leads to a more individualized follow-up schedule, allowing for a gradual return to the normal screening scheme. HPV testing should be routinely included (with or without cytology) in post-treatment follow-up of CIN2+ patients for early detection of recurrence and cancer progression. HPV genotyping methods, as a biological indicator of persistent disease, could be more suitable for a predictive role and risk stratification (particularly in the case of HPV 16/18 persistence) than pooled HPV-based testing. However, it is necessary to be aware of the performance of the system, adhering to strict standardization of the process and quality assurance criteria. PMID:26722366
Puill-Stephan, E.; van Oppen, M. J. H.; Pichavant-Rafini, K.; Willis, B. L.
2012-01-01
In sessile modular marine invertebrates, chimeras can originate from fusions of closely settling larvae or of colonies that come into contact through growth or movement. While it has been shown that juveniles of brooding corals fuse under experimental conditions, chimera formation in broadcast spawning corals, the most abundant group of reef corals, has not been examined. This study explores the capacity of the broadcast spawning coral Acropora millepora to form chimeras under experimental conditions and to persist as chimeras in the field. Under experimental conditions, 1.5-fold more larvae settled in aggregations than solitarily, and analyses of nine microsatellite loci revealed that 50 per cent of juveniles tested harboured different genotypes within the same colony. Significantly, some chimeric colonies persisted for 23 months post-settlement, when the study ended. Genotypes within persisting chimeric colonies all showed a high level of relatedness, whereas rejecting colonies displayed variable levels of relatedness. The nearly threefold greater sizes of chimeras compared with solitary juveniles, from settlement through to at least three months, suggest that chimerism is likely to be an important strategy for maximizing survival of vulnerable early life-history stages of corals, although longer-term studies are required to more fully explore the potential benefits of chimerism. PMID:21752820
Puill-Stephan, E; van Oppen, M J H; Pichavant-Rafini, K; Willis, B L
2012-02-22
In sessile modular marine invertebrates, chimeras can originate from fusions of closely settling larvae or of colonies that come into contact through growth or movement. While it has been shown that juveniles of brooding corals fuse under experimental conditions, chimera formation in broadcast spawning corals, the most abundant group of reef corals, has not been examined. This study explores the capacity of the broadcast spawning coral Acropora millepora to form chimeras under experimental conditions and to persist as chimeras in the field. Under experimental conditions, 1.5-fold more larvae settled in aggregations than solitarily, and analyses of nine microsatellite loci revealed that 50 per cent of juveniles tested harboured different genotypes within the same colony. Significantly, some chimeric colonies persisted for 23 months post-settlement, when the study ended. Genotypes within persisting chimeric colonies all showed a high level of relatedness, whereas rejecting colonies displayed variable levels of relatedness. The nearly threefold greater sizes of chimeras compared with solitary juveniles, from settlement through to at least three months, suggest that chimerism is likely to be an important strategy for maximizing survival of vulnerable early life-history stages of corals, although longer-term studies are required to more fully explore the potential benefits of chimerism.
Lucena-Padrós, Helena; Caballero-Guerrero, Belén; Maldonado-Barragán, Antonio; Ruiz-Barba, José Luis
2014-11-03
We have genotyped a total of 1045 microbial isolates obtained along the fermentation time of Spanish-style green table olives from the fermentation yards (patios) of two large manufacturing companies in the Province of Sevilla, south of Spain. Genotyping was carried out using RAPD-PCR fingerprinting. In general, isolates clustered well into the relevant phylogenetic dendrograms, forming separate groups in accordance to their species adscription. We could identify which bacterial and yeast genotypes (strains) persisted throughout the fermentation at each patio. Also, which of them were more adapted to any of the three stages, i.e. initial, middle and final, described for this food fermentation. A number of genotypes were found to be shared by both patios. Fifty seven of these belonged to five different bacterial species, i.e. Lactobacillus pentosus, Lactobacillus paracollinoides/collinoides, Lactobacillus rapi, Pediococcus ethanolidurans and Staphylococcus sp., although most of them (51) belonged to L. pentosus. Four yeast genotypes were also shared, belonging to the species Candida thaimueangensis, Saccharomyces cerevisiae and Hanseniaspora sp. Two genotypes of L. pentosus were found to be grouped with those of two strains used in commercially available starter cultures, one of them bacteriocinogenic, which were used up to three years before this study in these patios, demonstrating the persistence of selected strains in this environment. Biodiversity was assessed though different indexes, including richness, diversity and dominance. A statistically significant decrease in biodiversity between the initial and final stages of the fermentation was found in both patios. However, values of biodiversity indexes in the fermenters were very similar, and no significant differences were found in the total biodiversity between both patios. This study allowed us to identify a range of well adapted strains (genotypes), especially those belonging to the lactic acid bacteria, which could be useful to improve safety and quality of table olive fermentations. Copyright © 2014 Elsevier B.V. All rights reserved.
Oura, C A L; Bishop, R; Wampande, E M; Lubega, G W; Tait, A
2004-07-01
The 'Muguga cocktail' live vaccine comprises three Theileria parva stocks (Muguga, Kiambu 5 and the buffalo-derived Serengeti-transformed) and has been used extensively in Eastern, Central and Southern Africa with an infection and treatment protocol to protect cattle against East Coast fever. We report the characterization of the three component vaccine stocks using a panel of polymorphic micro-satellite and mini-satellite markers and the development of a stock-derived PCR method that distinguishes two of the vaccine stocks. These markers, with the use of a recently developed Reverse Line Blot assay, have enabled us to address four important questions in relation to vaccination. First, how closely related are the vaccine stocks, secondly do all three stocks persist post-vaccination and induce a carrier state, thirdly is there evidence for the transmission of the vaccine stocks and fourthly does vaccination prevent infection with local genotypes? The results show that Muguga and Serengeti-transformed stocks are highly related but very distinct from Kiambu 5 that persists in vaccinated cattle establishing a carrier state. No evidence was obtained for the transmission of vaccine stocks to co-grazed animals, although these animals were infected with up to 8 different T. parva genotypes showing there was a significant level of tick challenge. Some of the vaccinated animals become infected with a subset of local genotypes providing evidence for limited vaccine 'breakthrough'.
Ahlen, Catrine; Aas, Marianne; Krusnell, Jadwiga; Iversen, Ole-Jan
2016-01-01
Recurrent legionella outbreaks at one and the same location are common. We have identified a single Legionella pneumophila genotype associated with recurrent Legionella outbreaks over 6 years. Field emergency surveys following Legionella outbreaks were performed on a vessel in 2008, 2009 and 2013. Water samples from both the distribution and technical parts of the potable water system were analyzed with respect to L. pneumophila [Real-Time PCR, cultivation, serotyping and genotyping (PFGE)] and free-living amoebae, (FLA). Legionella pneumophila serogroup 1 was present in the ship's potable water system during every outbreak. Genotyping of the 2008 survey material showed two separate PFGE genotypes while those in 2009 and 2013 demonstrated the presence of only one of the two genotypes. FLA with intracellular L. pneumophila of the same genotype were also detected. Analyses of the freshwater system on a ship following three separate Legionella outbreaks, for L. pneumophila and FLAs, revealed a single L. pneumophila genotype and FLA (Hartmanella). It is reasonable to assume that the L. pneumophila genotype detected in the freshwater system was the causal agent in the outbreaks onboard. Persistence of an apparently low-pathogenic L. pneumophila genotype and FLA in a potable water system represent a potential risk for recurrent outbreaks.
Emanuelsson, I M
2001-01-01
Mutans streptococci (MS) are bacteria showing several cariogenic traits. This thesis is based on the concept that humans acquire MS directly or indirectly from each other. Previous research on the transmission of the bacteria in families has indicated that children acquire MS from their mothers. Just a few studies have included fathers. Diverging results have been presented about spouses acquiring MS from each other. The information on the distribution of MS types at a tooth surface level has been limited. The methods used for identification of MS types have been refined during the years making further studies in the field interesting. The present thesis deals primarily with the distribution of MS in families. Twenty-five Swedish families including a 3-year-old first-born child (I) and 11 corresponding Chinese families (II) were studied. The Swedish families were followed up 2-5 years later (III and IV). Study V deals with the colonization of MS on tooth sites in 13 young adults. MS were isolated from bacterial plaque samples obtained from the teeth of the subjects. Identification of MS types was carried out through DNA analysis methods, REA and RAPD respectively. MS were detected in 11 of the 25 Swedish children. The distribution of MS genotypes in these families indicated that the mothers and individuals outside the family were the sources of MS to the children (I). The distribution of MS genotypes in the Chinese families (II) pointed to the fact that the father played a more pronounced role as MS source compared to in the Swedish families. The intra-familial distribution of MS seemed to be different in the two groups of families with different cultural backgrounds. At the follow-up, genotypes of MS were found again among the MS positive children and their parents. This indicated that genotypes of MS persisted. Even though some alterations in the prevalence of MS genotypes were shown (III). Among the MS negative children some had acquired the bacteria, but most of them remained MS negative by the age of 5-8 years (IV). The father was in some few cases the MS source to the child in the Swedish families (III, IV). Few spouses acquired MS from each other. It is not clear to which extent the parents' salivary levels of MS, caregiver of the child, breast-feeding or antibiotic treatment influenced the acquisition of MS in the groups studied (I-IV). Finally it was shown that several different genotypes of MS colonized a particular tooth site simultaneously. Within each individual the same genotype occurred on two or more tooth sites. Genotypes persisted 4-7 months on their site. The colonization diverged inter-individually in terms of the number and the distribution of MS genotypes on the tooth sites (V).
Sadr, Karim; Bousman, C. Britt; Brown, Thomas A.; ...
2017-09-20
In this paper, we present that five centuries ago, the first European mariners rounding the Cape of Good Hope encountered Khoekhoe-speaking people who occasionally supplied beef and mutton in return for iron, tobacco, alcohol and other exotic goods. The origin of their livestock, as well as of the Khoekhoen themselves, continues to intrigue academics. We now know the first livestock were introduced from the north and that they reached southern Africa over 2000 years ago (Robbins et al. 2005; Pleurdeau et al. 2012). Y-chromosome E3b1f-M293 (Henn et al. 2008) and lactase persistence allele -14010*C (Macholdt et al. 2014) indicate thatmore » some Khoe-speakers are distantly related through the male lineage to pastoralists in East Africa (Barbieri et al. 2014); a conclusion that is supported by linguists who locate the origins of proto-Khoe languages in that part of the continent (e.g., Güldemann 2008). But it remains unclear whether the earliest livestock in southern Africa arrived with immigrant Khoespeakers, or whether the Khoe-speakers arrived later: the first livestock may have been traded down the line or infiltrated among southern African San hunter-gatherers (e.g., Sadr 2015).« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sadr, Karim; Bousman, C. Britt; Brown, Thomas A.
In this paper, we present that five centuries ago, the first European mariners rounding the Cape of Good Hope encountered Khoekhoe-speaking people who occasionally supplied beef and mutton in return for iron, tobacco, alcohol and other exotic goods. The origin of their livestock, as well as of the Khoekhoen themselves, continues to intrigue academics. We now know the first livestock were introduced from the north and that they reached southern Africa over 2000 years ago (Robbins et al. 2005; Pleurdeau et al. 2012). Y-chromosome E3b1f-M293 (Henn et al. 2008) and lactase persistence allele -14010*C (Macholdt et al. 2014) indicate thatmore » some Khoe-speakers are distantly related through the male lineage to pastoralists in East Africa (Barbieri et al. 2014); a conclusion that is supported by linguists who locate the origins of proto-Khoe languages in that part of the continent (e.g., Güldemann 2008). But it remains unclear whether the earliest livestock in southern Africa arrived with immigrant Khoespeakers, or whether the Khoe-speakers arrived later: the first livestock may have been traded down the line or infiltrated among southern African San hunter-gatherers (e.g., Sadr 2015).« less
Sherenian, M G; Cho, S H; Levin, A; Min, J-Y; Oh, S S; Hu, D; Galanter, J; Sen, S; Huntsman, S; Eng, C; Rodriguez-Santana, J R; Serebrisky, D; Avila, P C; Kalhan, R; Smith, L J; Borrell, L N; Seibold, M A; Keoki Williams, L; Burchard, E G; Kumar, R
2017-09-01
PAI-1 gain-of-function variants promote airway fibrosis and are associated with asthma and with worse lung function in subjects with asthma. We sought to determine whether the association of a gain-of-function polymorphism in plasminogen activator inhibitor-1 (PAI-1) with airway obstruction is modified by asthma status, and whether any genotype effect persists after accounting for common exposures that increase PAI-1 level. We studied 2070 Latino children (8-21y) with genotypic and pulmonary function data from the GALA II cohort. We estimated the relationship of the PAI-1 risk allele with FEV1/FVC by multivariate linear regression, stratified by asthma status. We examined the association of the polymorphism with asthma and airway obstruction within asthmatics via multivariate logistic regression. We replicated associations in the SAPPHIRE cohort of African Americans (n=1056). Secondary analysis included the effect of the at-risk polymorphism on postbronchodilator lung function. There was an interaction between asthma status and the PAI-1 polymorphism on FEV 1 /FVC (P=.03). The gain-of-function variants, genotypes (AA/AG), were associated with lower FEV 1 /FVC in subjects with asthma (β=-1.25, CI: -2.14,-0.35, P=.006), but not in controls. Subjects with asthma and the AA/AG genotypes had a 5% decrease in FEV 1 /FVC (P<.001). In asthmatics, the risk genotype (AA/AG) was associated with a 39% increase in risk of clinically relevant airway obstruction (OR=1.39, CI: 1.01, 1.92, P=.04). These associations persisted after exclusion of factors that increase PAI-1 including tobacco exposure and obesity. The decrease in the FEV 1 /FVC ratio associated with the risk genotype was modified by asthma status. The genotype increased the odds of airway obstruction by 75% within asthmatics only. As exposures known to increase PAI-1 levels did not mitigate this association, PAI-1 may contribute to airway obstruction in the context of chronic asthmatic airway inflammation. © 2017 John Wiley & Sons Ltd.
Recent advances on lactose intolerance: Tolerance thresholds and currently available answers.
Corgneau, M; Scher, J; Ritie-Pertusa, L; Le, D T L; Petit, J; Nikolova, Y; Banon, S; Gaiani, C
2017-10-13
The genetically programmed reduction in lactase activity during adulthood affects 70% of the world adult population and can cause severe digestive disorders, which are the sign of lactose intolerance. Lactose intolerance symptoms vary depending on the residual lactase activity, the small bowel transit time, and especially the amount of ingested lactose. To formulate dairy products suitable for the vast majority of lactose intolerants, it is essential to define lactose intolerance threshold. A recent meta-analysis permitted to show that almost all lactose intolerants tolerate 12 g of lactose in one intake and approximately 18 g of lactose spread over the day. The prevalence and severity of lactose intolerance are probably overestimated by the general public. This misconception usually leads to an unnecessary reduction of dairy foodstuff consumption. Nevertheless, dairy products are essential for health mainly due to their calcium content and the positive influence of probiotic bacteria. The formulation of dairy products suitable for most intolerant and suspicious subjects seems necessary. The use of exogenous enzyme preparations, as well as the consumption of lactose-free products or products rich in probiotic bacteria are proposed as symptom-reducing strategies.
Genotyping of polyomavirus BK by Real Time PCR for VP1 gene.
Gambarino, Stefano; Costa, Cristina; Astegiano, Sara; Piasentin, Elsa Alessio; Segoloni, Giuseppe P; Cavallo, Rossana; Bergallo, Massimiliano
2011-10-01
Polyomavirus BK latently persist in different sites, including the renourinary tract, and may reactivate causing nephropathy in renal transplant recipients or hemorrhagic cystitis in bone marrow recipients. Based on the sequence of the VP1 gene, four genotypes have been described, corresponding to the four serologically differentiated subtypes I-IV, with different prevalence and geographic distribution. In this study, the development and clinical validation of four different Real-Time PCR assays for the detection and discrimination of BKV genotypes as a substitute of DNA sequencing are described. 379 BK VP1 sequences, belonging to the main four genotypes, were aligned and "hot spots" of mutation specific for all the strains or isolates were identified. Specific primers and probes for the detection and discrimination of each genotype by four Real-Time PCR assays were designed and technically validated. Subsequently, the four Real-Time PCR assays were used to test 20 BK-positive urine specimens from renal transplant patients, and evidenced a prevalence of BK genotype I, as previously reported in Europe. Results were confirmed by sequencing. The availability of a rapid and simple genotyping method could be useful for the evaluation of BK genotypes prevalence and studies on the impact of the infecting genotype on viral biological behavior, pathogenic role, and immune evasion strategies.
Peng, X M; Lei, R X; Gu, L; Ma, H H; Xie, Q F; Gao, Z L
2007-10-01
The influence of human genetics on the natural history of hepatitis B virus (HBV) infection may be diminished in endemic areas because infection at a young age predisposes to chronic HBV infection. The present study aimed to address this issue through the determination of the influences of single nucleotide polymorphisms (SNPs) of myxovirus resistence-1 (MxA) -88 G/T and interferon (IFN)-gamma +874 A/T on the natural history of HBV infection in endemic regions. One hundred adult patients with self-limiting HBV infection (positive for both anti-HBs and anti-HBc) and 340 adult patients with persistent HBV infection were recruited from southern China, an endemic area with an HBsAg carrier rate of 17.8%. SNPs of MxA -88 G/T and interferon (IFN)-gamma +874 A/T were typed using a protocol based on competitively differentiated polymerase chain reaction. A highly significant difference in the distribution of MxA -88 G/T was observed between those with persistent and self-limiting HBV infections. The latter displayed a lower frequency of the GG genotype (41.0% vs. 52.9%, P = 0.036) and a higher frequency of the TT genotype (16.0% vs. 2.4%, P = 0.000), compared to patients with persistent infection. These differences were not gender- or age-specific. However, a significant distribution difference of IFN-gamma +874 A/T was not observed. Between two groups of patients, respectively, the distribution frequencies of the AA genotype (65.0% vs. 72.8%, P = 0.139) and the TT genotype (2.0% vs. 1.2%, P = 0.894) were found. These results suggest that MxA gene -88 G/T and IFN-gamma +874 A/T behave differently in endemic HBV infections. Further study is necessary to clarify the influences of human genetics on endemic HBV infections.
Wang, Sophia S; Bratti, M Concepcion; Rodríguez, Ana Cecilia; Herrero, Rolando; Burk, Robert D; Porras, Carolina; González, Paula; Sherman, Mark E; Wacholder, Sholom; Lan, Z Elizabeth; Schiffman, Mark; Chanock, Stephen J; Hildesheim, Allan
2009-01-01
We examined host genetic factors to identify those more common in individuals whose human papillomavirus (HPV) infections were most likely to persist and progress to cervical intraepithelial neoplasia grade 3 (CIN3) and cancer. We genotyped 92 single-nucleotide polymorphisms (SNPs) from 49 candidate immune response and DNA repair genes obtained from 469 women with CIN3 or cancer, 390 women with persistent HPV infections (median duration, 25 months), and 452 random control subjects from the 10,049-woman Guanacaste Costa Rica Natural History Study. We calculated odds ratios and 95% confidence intervals (CIs) for the association of SNP and haplotypes in women with CIN3 or cancer and HPV persistence, compared with random control subjects. A SNP in the Fanconi anemia complementation group A gene (FANCA) (G501S) was associated with increased risk of CIN3 or cancer. The AG and GG genotypes had a 1.3-fold (95% CI, 0.95-1.8-fold) and 1.7-fold (95% CI, 1.1-2.6-fold) increased risk for CIN3 or cancer, respectively (P(trend) = .008; referent, AA). The FANCA haplotype that included G501S also conferred increased risk of CIN3 or cancer, as did a different haplotype that included 2 other FANCA SNPs (G809A and T266A). A SNP in the innate immune gene IRF3 (S427T) was associated with increased risk for HPV persistence (P(trend) = .009). Our results require replication but support the role of FANCA variants in cervical cancer susceptibility and of IRF3 in HPV persistence.
Schönhusen, U; Junghans, P; Flöter, A; Steinhoff-Wagner, J; Görs, S; Schneider, F; Metges, C C; Hammon, H M
2013-04-01
The study was designed to examine whether feeding soy protein isolate as partial replacement of casein (CN) affects glucose metabolism in young goats and whether effects may be ameliorated by supplementation of those AA known to be lower concentrated in soy than in CN. Goat kids (d 20 of age) were fed comparable milk protein diets, in which 50% of the crude protein was either CN (control, CON), soy protein isolate (SPI), or soy protein isolate supplemented with AA (SPIA) for 43 d (n=8 per group). On d 62 of age, a single bolus dose of d-[(13)C6]glucose (10mg/kg of BW) was given with the morning diet, and simultaneously, a single bolus dose of d-[6,6-(2)H2]glucose (5mg/kg of BW) was injected into a jugular vein. Blood samples were collected between -30 and +420 min relative to the tracer administration to measure the (13)C and (2)H enrichments of plasma glucose and the (13)C enrichment of blood CO2. Glucose first-pass uptake by the splanchnic tissues was calculated from the rate of appearance of differentially labeled glucose tracer in plasma. Glucose oxidation was calculated from (13)C enrichment in blood CO2. In addition, plasma concentrations of triglycerides, nonesterified fatty acids, glucose, insulin, and glucagon were measured. On d 63 of age, kids were killed and jejunal mucosa and liver samples were collected to measure lactase mRNA levels and lactase and maltase activities in the jejunum and activities of pyruvate carboxylase and phosphoenolpyruvate carboxykinase (PEPCK) in the liver. Basal plasma glucose concentration tended to be higher in the CON than the SPIA group, whereas basal insulin was higher in the CON group than the SPI and SPIA groups, and glucagon was higher in the CON than the SPIA group. Plasma glucose and insulin concentrations increased during the first hour after feeding, whereas plasma glucagon increased immediately after feeding and after 1h of feeding. First-pass uptake and glucose oxidation were not affected by diet. Maltase activities in proximal and mid jejunum and lactase activities in mid jejunum were lower in the CON than in the SPIA group. Activities of PEPCK were higher in the SPIA than in the SPI group. In conclusion, feeding milk diets with soy protein isolate seems to affect glucose status in kids, but has no effect on first-pass uptake and oxidation of glucose. The highest activities of lactase and maltase were observed after supplementation with AA. Higher PEPCK activities in the liver may point at elevated gluconeogenic activities after AA supplementation in soy-fed kids. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
de Pokomandy, Alexandra; Kaufman, Elaina; de Castro, Christina; Mayrand, Marie-Hélène; Burchell, Ann N; Klein, Marina; Charest, Louise; Auger, Manon; Rodrigues-Coutlée, Sophie; Coutlée, François
2017-08-15
The risk of anal cancer due to high-risk human papillomavirus (HR-HPV) is higher in women living with human immunodeficiency virus (HIV) than in the general population. We present findings of cervical and anal HPV and cytologic tests at baseline in the EVVA cohort study and HPV persistence data 6 months after baseline. Semiannual visits included questionnaires, chart reviews, cervical/anal cytologic and cervical/anal HPV testing for 2 years. Genotyping for 36 HPV genotypes was performed using the Roche Linear Array HPV genotyping test. A total of 151 women living with HIV were recruited. At baseline, 75% had anal HPV, 51% had anal HR-HPV, 50% had cervical HPV, and 29% had cervical HR-HPV. Anal HPV-16 and HPV-51 were more frequent in women born in Canada (31% and 29%, respectively, compared with ≤16% for other women). Most anal HR-HPV types detected at 6 months (57%-93%) were persistent from baseline. Findings of anal cytologic tests were abnormal for 37% of women. Anal HPV is highly prevalent in women living with HIV, and type distribution varies by place of birth. High-resolution anoscopy was indicated in more than one third of results. As anal cancer is potentially preventable, these important findings need to be considered when selecting the best approach for anal cancer screening programs. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.
Plentz, Annelie; Würdinger, Michael; Kudlich, Matthias; Modrow, Susanne
2013-10-01
After acute parvovirus B19 (B19V) infection of immunocompetent individuals, viral genomes persist lifelong in various tissues. In immunocompromized patients, acute B19V infection may be associated with severe anaemia. It is unclear whether reactivation of latent B19V DNA may contribute to persistent viraemia and anaemia in transplant recipients. We retrospectively analysed the impact of B19V infection in 371 adult transplant recipients (kidney, liver, heart, bone marrow). The patients' pre-transplantation serostatus was determined. 1431 sera or plasmas obtained in monthly intervals during six months following transplantation were analysed for the presence of B19V DNA by quantitative PCR which allows discrimination between B19V genotypes 1-3. Overall, 82% of the patients were seropositive. B19V DNA (<600-1100 geq/ml) was detected in 4.0% of patients and classified as genotype 1 in 12, genotype 2 in one and genotype 3 in two patients. Whereas 5.5%, 6.7% and 5.7% of liver, heart and bone marrow recipients displayed DNAemia, viral genomes were detected only in 1.4% of kidney recipients. Haemoglobin levels and reticulocyte counts showed no differences between DNAemic and non-DNAemic patients. In a control group of 120 healthy subjects, 78% were seropositive and 2.5% displayed DNAemia. Prevalence and level of B19V DNAemia in adult transplant recipients was comparable to that observed in healthy individuals, but with a distinct accumulation within the first weeks post-transplantation. The presence of low-level DNAemia in transplant recipients was not associated with anaemia. Copyright © 2013 Elsevier B.V. All rights reserved.
Tayib, Shahila; Allan, Bruce; Williamson, Anna-Lise; Denny, Lynette
2015-09-21
Genital human papillomavirus (HPV) infection is the most common sexually transmitted viral disease in the world. HPV infection of the genital epithelium is associated with genital warts and malignancies of the lower genital tract. To describe the distribution, phenotypic appearance and HPV type associated with genital warts in women. This was a prospective observational study of all women with genital warts who attended the Colposcopy Clinic, Groote Schuur Hospital, Cape Town, South Africa, during 2010 and fulfilled the inclusion and exclusion criteria. One hundred and thirteen women were tested for HPV using the Roche Linear Array HPV genotyping kit to determine the HPV genotypes causing genital warts. The median age of the women was 27 years (range 15 - 53); 90 (79.6%) were HIV-positive, and two-thirds were on antiretroviral treatment. Treatment involved ablation with topical agents, cauterisation or carbon dioxide laser. At 3 months' follow-up after treatment, 56.6% of the women, the majority of whom were HIV-positive, had recurrent/persistent disease. In both HIV-positive and HIV-negative women, HPV was detected in over 90% of cases. However, over half the HIV-positive women as opposed to 2/18 of the HIV-negative women were infected with multiple HPV genotypes. The commonest HPV genotypes in HIV-positive and HIV-negative women were types 11, 6, 89, 61, 55 and 62 and types 11 and 6, respectively. The majority of the patients were HIV-positive and had multiple HPV infections. While this did not alter the phenotypic appearance of the warts, recurrence/persistence after treatment was more common.
Real-time PCR for simultaneous detection and genotyping of bovine viral diarrhea virus.
Letellier, C; Kerkhofs, P
2003-12-01
Since two genotypes of bovine viral diarrhea viruses (BVDV) occur in Belgian herds, their differentiation is important for disease surveillance. A quantitative real-time PCR assay was developed to detect and classify bovine viral diarrhea viruses in genotype I and II. A pair of primers specific for highly conserved regions of the 5'UTR and two TaqMan probes were designed. The FAM and VIC-labeled probe sequences differed by three nucleotides, allowing the differentiation between genotype I and II. The assay detectability of genotype I and II real-time PCR assay was 1000 and 100 copies, respectively. Highly reproducible data were obtained as the coefficients of variation of threshold cycle values in inter-runs were less than 2.2%. The correct classification of genotype I and II viruses was assessed by using reference strains and characterized field isolates of both genotypes. The application to clinical diagnosis was evaluated on pooled blood samples by post run measurement of the FAM- and VIC-associated fluorescence. The 100% agreement with the conventional RT-PCR method confirmed that this new technique could be used for routine detection of persistently infected immunotolerant animals.
History of Newcastle disease in South Africa.
Abolnik, Celia
2017-02-24
Poultry production in South Africa, a so-called developing country, may be seen as a gradient between two extremes with highly integrated commercial enterprises with world-class facilities on one hand and unimproved rural chickens kept by households and subsistence farmers on the other. Although vaccination against Newcastle disease is widely applied to control this devastating infection, epizootics continue to occur. Since the first official diagnosis in 1945, through the sporadic outbreaks of the 1950s and early 1960s, to serious epizootics caused by genotype VIII (late 1960s-2000), genotype VIIb (1993-1999), genotype VIId (2003-2012) and most recently genotype VIIh (2013 to present), South Africa's encounters with exotic Newcastle disease follow global trends. Importation - probably illegal - of infected poultry, poultry products or exotic birds and illegal swill dumping are likely routes of entry. Once the commercial sector is affected, the disease spreads rapidly within the region via transportation routes. Each outbreak genotype persisted for about a decade and displaced its predecessor.
Kim, Jae-Min; Stewart, Robert; Kang, Hee-Ju; Bae, Kyung-Yeol; Kim, Sung-Wan; Shin, Il-Seon; Hong, Young Joon; Ahn, Youngkeun; Jeong, Myung Ho; Park, Sung-Woo; Kim, Young-Hoon; Yoon, Jin-Sang
2015-06-01
Genes coding for the serotonergic pathway have been associated with depressive disorders. However, these associations have rarely been tested in acute coronary syndrome (ACS) patients vulnerable to depression. This study aimed to investigate whether polymorphisms of serotonin transporter (5-HTT) and serotonin 2a receptor (5-HTR2a) genes are associated with occurrence of depressive disorder in ACS. 969 patients with recently developed ACS were recruited at baseline, and 711 were followed 1 year thereafter. Depressive disorder was diagnosed according to DSM-IV criteria, and analysed as an outcome at baseline (prevalence), and follow up (incidence and persistence). Genotypes were ascertained for 5-HTTLPR, STin2 VNTR, 5-HTR2a 102T/C, and 5-HTR2a 1438A/G. Logistic regression models were used to investigate associations. The 5-HTTLPR s/s genotype was independently associated with depressive disorder prevalence and persistence following ACS, but no significant associations were found with the other polymorphisms. ACS patients with the 5-HTTLPR s allele are thus potentially susceptible to depressive disorder in the early phase after ACS, and with its persistence over the subsequent year. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.
Mortensen, Klaus Leth; Jensen, Rasmus Hare; Johansen, Helle Krogh; Skov, Marianne; Pressler, Tacjana; Howard, Susan Julie; Leatherbarrow, Howard; Mellado, Emilia; Arendrup, Maiken Cavling
2011-06-01
Respiratory tract colonization by molds in patients with cystic fibrosis (CF) were analyzed, with particular focus on the frequency, genotype, and underlying mechanism of azole resistance among Aspergillus fumigatus isolates. Clinical and demographic data were also analyzed. A total of 3,336 respiratory samples from 287 CF patients were collected during two 6-month periods in 2007 and 2009. Azole resistance was detected using an itraconazole screening agar (4 mg/liter) and the EUCAST method. cyp51A gene sequencing and microsatellite genotyping were performed for isolates from patients harboring azole-resistant A. fumigatus. Aspergillus spp. were present in 145 patients (51%), of whom 63 (22%) were persistently colonized. Twelve patients (4%) harbored other molds. Persistently colonized patients were older, provided more samples, and more often had a chronic bacterial infection. Six of 133 patients (4.5%) harbored azole-nonsusceptible or -resistant A. fumigatus isolates, and five of those six patients had isolates with Cyp51A alterations (M220K, tandem repeat [TR]/L98H, TR/L98H-S297T-F495I, M220I-V101F, and Y431C). All six patients were previously exposed to azoles. Genotyping revealed (i) microevolution for A. fumigatus isolates received consecutively over the 2-year period, (ii) susceptible and resistant isolates (not involving TR/L98H isolates) with identical or very closely related genotypes (two patients), and (iii) two related susceptible isolates and a third unrelated resistant isolate with a unique genotype and the TR/L98H resistance combination (one patient). Aspergilli were frequently found in Danish CF patients, with 4.5% of the A. fumigatus isolates being azole nonsusceptible or resistant. Genotyping suggested selection of resistance in the patient as well as resistance being achieved in the environment.
Transforming growth factor- 1 C-509T polymorphism, oxidant stress, and early-onset childhood asthma.
Salam, Muhammad T; Gauderman, W James; McConnell, Rob; Lin, Pi-Chu; Gilliland, Frank D
2007-12-15
Transforming growth factor (TGF)-beta1 is involved in airway inflammation and remodeling, two key processes in asthma pathogenesis. Tobacco smoke and traffic emissions induce airway inflammation and modulate TGF-beta1 gene expression. We hypothesized that the effects of functional TGF-beta1 variants on asthma occurrence vary by these exposures. We tested these hypotheses among 3,023 children who participated in the Children's Health Study. Tagging single-nucleotide polymorphisms rs4803457 C>T and C-509T (a functional promoter polymorphism) accounted for 94% of the haplotype diversity of the upstream region. Exposure to maternal smoking in utero was based on smoking by biological mother during pregnancy. Residential distance from nearest freeway was calculated based on residential address at study entry. Children with the -509TT genotype had a 1.8-fold increased risk of early persistent asthma (95% confidence interval [CI], 1.11-2.95). This association varied marginally significantly by in utero exposure to maternal smoking. Compared with children with the -509CC/CT genotype with no in utero exposure to maternal smoking, those with the -509TT genotype with such exposure had a 3.4-fold increased risk of early persistent asthma (95% CI, 1.46-7.80; interaction, P = 0.11). The association between TGF-beta1 C-509T and lifetime asthma varied by residential proximity to freeways (interaction P = 0.02). Children with the -509TT genotype living within 500 m of a freeway had over three-fold increased lifetime asthma risk (95% CI, 1.29-7.44) compared with children with CC/CT genotype living > 1500 m from a freeway. Children with the TGF-beta1 -509TT genotype are at increased risk of asthma when they are exposed to maternal smoking in utero or to traffic-related emissions.
Insect herbivory and plant adaptation in an early successional community.
Agrawal, Anurag A; Hastings, Amy P; Fines, Daniel M; Bogdanowicz, Steve; Huber, Meret
2018-05-01
To address the role of insect herbivores in adaptation of plant populations and the persistence of selection through succession, we manipulated herbivory in a long-term field experiment. We suppressed insects in half of 16 plots over nine years and examined the genotypic structure and chemical defense of common dandelion (Taraxacum officinale), a naturally colonizing perennial apomictic plant. Insect suppression doubled dandelion abundance in the first few years, but had negligible effects thereafter. Using microsatellite DNA markers, we genotyped >2500 plants and demonstrate that insect suppression altered the genotypic composition of plots in both sampling years. Phenotypic and genotypic estimates of defensive terpenes and phenolics from the field plots allowed us to infer phenotypic plasticity and the response of dandelion populations to insect-mediated natural selection. The effects of insect suppression on plant chemistry were, indeed, driven both by plasticity and plant genotypic identity. In particular, di-phenolic inositol esters were more abundant in plots exposed to herbivory (due to the genotypic composition of the plots) and were also induced in response to herbivory. This field experiment thus demonstrates evolutionary sorting of plant genotypes in response to insect herbivores that was in same direction as the plastic defensive response within genotypes. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.
Predictive value of homocysteine for depression after acute coronary syndrome
Kang, Hee Ju; Stewart, Robert; Bae, Kyung Yeol; Kim, Sung Wan; Shin, Il Seon; Kang, Hyuno; Moon, Won Jin; Hong, Young Joon; Ahn, Youngkeun; Jeong, Myung Ho; Yoon, Jin Sang; Kim, Jae Min
2016-01-01
We investigated roles of plasma homocysteine and MTHFR gene in relation to risks and treatment responses of depression in ACS. A sample of 969 patients with recent ACS were recruited and 711 followed 1 year later. In addition, of 378 baseline participants with depressive disorder, 255 were randomized to a 24-week double blind trial of escitalopram (N = 127) or placebo (N = 128). A higher homocysteine concentration was independently associated with prevalent depressive disorder at baseline irrespective of MTHFR genotype; and with both incident and persistent depressive disorder at follow-up only in the presence of TT genotype. MTHFR genotype was not itself associated with depressive disorder after ACS. No associations were found with 24-week antidepressant treatment responses. Plasma homocysteine could be a biomarker for depressive disorder particularly in the acute phase of ACS. Focused interventions for those with higher homocysteine level and MTHFR TT genotype might reduce the risk of later depressive disorder. PMID:27626182
Genomic prediction using imputed whole-genome sequence data in Holstein Friesian cattle.
van Binsbergen, Rianne; Calus, Mario P L; Bink, Marco C A M; van Eeuwijk, Fred A; Schrooten, Chris; Veerkamp, Roel F
2015-09-17
In contrast to currently used single nucleotide polymorphism (SNP) panels, the use of whole-genome sequence data is expected to enable the direct estimation of the effects of causal mutations on a given trait. This could lead to higher reliabilities of genomic predictions compared to those based on SNP genotypes. Also, at each generation of selection, recombination events between a SNP and a mutation can cause decay in reliability of genomic predictions based on markers rather than on the causal variants. Our objective was to investigate the use of imputed whole-genome sequence genotypes versus high-density SNP genotypes on (the persistency of) the reliability of genomic predictions using real cattle data. Highly accurate phenotypes based on daughter performance and Illumina BovineHD Beadchip genotypes were available for 5503 Holstein Friesian bulls. The BovineHD genotypes (631,428 SNPs) of each bull were used to impute whole-genome sequence genotypes (12,590,056 SNPs) using the Beagle software. Imputation was done using a multi-breed reference panel of 429 sequenced individuals. Genomic estimated breeding values for three traits were predicted using a Bayesian stochastic search variable selection (BSSVS) model and a genome-enabled best linear unbiased prediction model (GBLUP). Reliabilities of predictions were based on 2087 validation bulls, while the other 3416 bulls were used for training. Prediction reliabilities ranged from 0.37 to 0.52. BSSVS performed better than GBLUP in all cases. Reliabilities of genomic predictions were slightly lower with imputed sequence data than with BovineHD chip data. Also, the reliabilities tended to be lower for both sequence data and BovineHD chip data when relationships between training animals were low. No increase in persistency of prediction reliability using imputed sequence data was observed. Compared to BovineHD genotype data, using imputed sequence data for genomic prediction produced no advantage. To investigate the putative advantage of genomic prediction using (imputed) sequence data, a training set with a larger number of individuals that are distantly related to each other and genomic prediction models that incorporate biological information on the SNPs or that apply stricter SNP pre-selection should be considered.
Hajia, Massoud; Sohrabi, Amir
2018-03-27
Objective: Persistence of HPV infection is the true cause of cervical disorders. It is reported that competition may exist among HPV genotypes for colonization. This survey was designed to establish the multiple HPV genotype status in our community and the probability of multiple HPV infections involvement. Methods: All multiple HPV infections were selected for investigation in women suffering from genital infections referred to private laboratories in Tehran, Iran. A total of 160 multi HPV positive specimens from cervical scraping were identified by the HPV genotyping methods, "INNO-LiPA and Geno Array". Result: In present study, HPV 6 (LR), 16 (HR), 53 (pHR), 31 (HR) and 11 (LR) were included in 48.8% of detected infections as the most five dominant genotypes. HPV 16 was detected at the highest rate with genotypes 53, 31 and 52, while HPV 53 appeared linked with HPV 16, 51 and 56 in concurrent infections. It appears that HPV 16 and 53 may have significant tendencies to associate with each other rather than with other genotypes. Analysis of the data revealed there may be some synergistic interactions with a few particular genotypes such as "HPV 53". Conclusion: Multiple HPV genotypes appear more likely to be linked with development of cervical abnormalities especially in patients with genital infections. Since, there are various patterns of dominant HPV genotypes in different regions of world, more investigations of this type should be performed for careHPV programs in individual countries. Creative Commons Attribution License
Yang, Jian-Feng; Fox, Mark; Chu, Hua; Zheng, Xia; Long, Yan-Qin; Pohl, Daniel; Fried, Michael; Dai, Ning
2015-01-01
AIM: To validate 4-sample lactose hydrogen breath testing (4SLHBT) compared to standard 13-sample LHBT in the clinical setting. METHODS: Irritable bowel syndrome patients with diarrhea (IBS-D) and healthy volunteers (HVs) were enrolled and received a 10 g, 20 g, or 40 g dose lactose hydrogen breath test (LHBT) in a randomized, double-blinded, controlled trial. The lactase gene promoter region was sequenced. Breath samples and symptoms were acquired at baseline and every 15 min for 3 h (13 measurements). The detection rates of lactose malabsorption (LM) and lactose intolerance (LI) for a 4SLHBT that acquired four measurements at 0, 90, 120, and 180 min from the same data set were compared with the results of standard LHBT. RESULTS: Sixty IBS-D patients and 60 HVs were studied. The genotype in all participants was C/C-13910. LM and LI detection rates increased with lactose dose from 10 g, 20 g to 40 g in both groups (P < 0.001). 4SLHBT showed excellent diagnostic concordance with standard LHBT (97%-100%, Kappa 0.815-0.942) with high sensitivity (90%-100%) and specificity (100%) at all three lactose doses in both groups. CONCLUSION: Reducing the number of measurements from 13 to 4 samples did not significantly impact on the accuracy of LHBT in health and IBS-D. 4SLHBT is a valid test for assessment of LM and LI in clinical practice. PMID:26140004
Yang, Jian-Feng; Fox, Mark; Chu, Hua; Zheng, Xia; Long, Yan-Qin; Pohl, Daniel; Fried, Michael; Dai, Ning
2015-06-28
To validate 4-sample lactose hydrogen breath testing (4SLHBT) compared to standard 13-sample LHBT in the clinical setting. Irritable bowel syndrome patients with diarrhea (IBS-D) and healthy volunteers (HVs) were enrolled and received a 10 g, 20 g, or 40 g dose lactose hydrogen breath test (LHBT) in a randomized, double-blinded, controlled trial. The lactase gene promoter region was sequenced. Breath samples and symptoms were acquired at baseline and every 15 min for 3 h (13 measurements). The detection rates of lactose malabsorption (LM) and lactose intolerance (LI) for a 4SLHBT that acquired four measurements at 0, 90, 120, and 180 min from the same data set were compared with the results of standard LHBT. Sixty IBS-D patients and 60 HVs were studied. The genotype in all participants was C/C-13910. LM and LI detection rates increased with lactose dose from 10 g, 20 g to 40 g in both groups (P < 0.001). 4SLHBT showed excellent diagnostic concordance with standard LHBT (97%-100%, Kappa 0.815-0.942) with high sensitivity (90%-100%) and specificity (100%) at all three lactose doses in both groups. Reducing the number of measurements from 13 to 4 samples did not significantly impact on the accuracy of LHBT in health and IBS-D. 4SLHBT is a valid test for assessment of LM and LI in clinical practice.
[Lactose-containing tablets for patients with lactose intolerance?].
Picksak, Gesine; Stichtenoth, Dirk O
2009-01-01
Lactose is often used as an excipient in tablets because of its ideal characteristics. Most patients with lactose intolerance tolerate small amounts of lactose. However, the nocebo effect must be considered. Thus, patients should be informed about the very small amounts of lactose in the medication. If the patient is still suffering from gastrointestinal symptoms and there is no lactose-free alternative, the enzyme lactase can be substituted individually.
Proceedings of the Natick Science Symposium (4th) Held in Natick, Massachusetts on 9-10 June 1992
1992-09-01
HQ - hydroquinone; MG - methyl gallate; CA - caffeic acid ; CHIA - chlorogenic acid ; GA - gallic acid ; FOLY - polymeric antioxidant. Values shown...examples 268 FQRrER & BIACK (qu~tin, hydroquinone, caffeic acid , chlorogenic acid and gallic acid ) , these are relatively ineffective in HSV...unless covalently bonded to the membrane. 279 SENECAL & RAND A membrane lactase reactor, modelled after the mammalian small intestine, has been
Lactose malabsorption and intolerance: pathogenesis, diagnosis and treatment.
Misselwitz, Benjamin; Pohl, Daniel; Frühauf, Heiko; Fried, Michael; Vavricka, Stephan R; Fox, Mark
2013-06-01
Lactose malabsorption is a common condition caused by reduced expression or activity of lactase in the small intestine. In such patients, lactose intolerance is characterized by abdominal symptoms (e.g. nausea, bloating, and pain) after ingestion of dairy products. The genetic basis of lactose malabsorption is established and several tests for this condition are available, including genetic, endoscopic, and H2-breath tests. In contrast, lactose intolerance is less well understood. Recent studies show that the risk of symptoms after lactose ingestion depends on the dose of lactose, lactase expression, intestinal flora, and sensitivity of the gastrointestinal tract. Lactose intolerance has recently been defined as symptoms developing after ingestion of lactose which do not develop after placebo challenge in a person with lactose maldigestion. Such blinded testing might be especially important in those with functional gastrointestinal diseases in whom self-reported lactose intolerance is common. However, placebo-controlled testing is not part of current clinical practice. Updated protocols and high-quality outcome studies are needed. Treatment options of lactose intolerance include lactose-reduced diet and enzyme replacement. Documenting the response to multiple doses can guide rational dietary management; however, the clinical utility of this strategy has not been tested. This review summarizes the genetic basis, diagnosis, and treatment of lactose malabsorption and intolerance.
Novel epoxy activated hydrogels for solving lactose intolerance.
Elnashar, Magdy M M; Hassan, Mohamed E
2014-01-01
"Lactose intolerance" is a medical problem for almost 70% of the world population. Milk and dairy products contain 5-10% w/v lactose. Hydrolysis of lactose by immobilized lactase is an industrial solution. In this work, we succeeded to increase the lactase loading capacity to more than 3-fold to 36.3 U/g gel using epoxy activated hydrogels compared to 11 U/g gel using aldehyde activated carrageenan. The hydrogel's mode of interaction was proven by FTIR, DSC, and TGA. The high activity of the epoxy group was regarded to its ability to attach to the enzyme's -SH, -NH, and -OH groups, whereas the aldehyde group could only bind to the enzyme's -NH2 group. The optimum conditions for immobilization such as epoxy chain length and enzyme concentration have been studied. Furthermore, the optimum enzyme conditions were also deliberated and showed better stability for the immobilized enzyme and the Michaelis constants, K m and V max, were doubled. Results revealed also that both free and immobilized enzymes reached their maximum rate of lactose conversion after 2 h, albeit, the aldehyde activated hydrogel could only reach 63% of the free enzyme. In brief, the epoxy activated hydrogels are more efficient in immobilizing more enzymes than the aldehyde activated hydrogel.
Lactose Intolerance in Adults: Biological Mechanism and Dietary Management
Deng, Yanyong; Misselwitz, Benjamin; Dai, Ning; Fox, Mark
2015-01-01
Lactose intolerance related to primary or secondary lactase deficiency is characterized by abdominal pain and distension, borborygmi, flatus, and diarrhea induced by lactose in dairy products. The biological mechanism and lactose malabsorption is established and several investigations are available, including genetic, endoscopic and physiological tests. Lactose intolerance depends not only on the expression of lactase but also on the dose of lactose, intestinal flora, gastrointestinal motility, small intestinal bacterial overgrowth and sensitivity of the gastrointestinal tract to the generation of gas and other fermentation products of lactose digestion. Treatment of lactose intolerance can include lactose-reduced diet and enzyme replacement. This is effective if symptoms are only related to dairy products; however, lactose intolerance can be part of a wider intolerance to variably absorbed, fermentable oligo-, di-, monosaccharides and polyols (FODMAPs). This is present in at least half of patients with irritable bowel syndrome (IBS) and this group requires not only restriction of lactose intake but also a low FODMAP diet to improve gastrointestinal complaints. The long-term effects of a dairy-free, low FODMAPs diet on nutritional health and the fecal microbiome are not well defined. This review summarizes recent advances in our understanding of the genetic basis, biological mechanism, diagnosis and dietary management of lactose intolerance. PMID:26393648
Lactose Intolerance in Adults: Biological Mechanism and Dietary Management.
Deng, Yanyong; Misselwitz, Benjamin; Dai, Ning; Fox, Mark
2015-09-18
Lactose intolerance related to primary or secondary lactase deficiency is characterized by abdominal pain and distension, borborygmi, flatus, and diarrhea induced by lactose in dairy products. The biological mechanism and lactose malabsorption is established and several investigations are available, including genetic, endoscopic and physiological tests. Lactose intolerance depends not only on the expression of lactase but also on the dose of lactose, intestinal flora, gastrointestinal motility, small intestinal bacterial overgrowth and sensitivity of the gastrointestinal tract to the generation of gas and other fermentation products of lactose digestion. Treatment of lactose intolerance can include lactose-reduced diet and enzyme replacement. This is effective if symptoms are only related to dairy products; however, lactose intolerance can be part of a wider intolerance to variably absorbed, fermentable oligo-, di-, monosaccharides and polyols (FODMAPs). This is present in at least half of patients with irritable bowel syndrome (IBS) and this group requires not only restriction of lactose intake but also a low FODMAP diet to improve gastrointestinal complaints. The long-term effects of a dairy-free, low FODMAPs diet on nutritional health and the fecal microbiome are not well defined. This review summarizes recent advances in our understanding of the genetic basis, biological mechanism, diagnosis and dietary management of lactose intolerance.
Lactose malabsorption and intolerance: pathogenesis, diagnosis and treatment
Pohl, Daniel; Frühauf, Heiko; Fried, Michael; Vavricka, Stephan R; Fox, Mark
2013-01-01
Lactose malabsorption is a common condition caused by reduced expression or activity of lactase in the small intestine. In such patients, lactose intolerance is characterized by abdominal symptoms (e.g. nausea, bloating, and pain) after ingestion of dairy products. The genetic basis of lactose malabsorption is established and several tests for this condition are available, including genetic, endoscopic, and H2-breath tests. In contrast, lactose intolerance is less well understood. Recent studies show that the risk of symptoms after lactose ingestion depends on the dose of lactose, lactase expression, intestinal flora, and sensitivity of the gastrointestinal tract. Lactose intolerance has recently been defined as symptoms developing after ingestion of lactose which do not develop after placebo challenge in a person with lactose maldigestion. Such blinded testing might be especially important in those with functional gastrointestinal diseases in whom self-reported lactose intolerance is common. However, placebo-controlled testing is not part of current clinical practice. Updated protocols and high-quality outcome studies are needed. Treatment options of lactose intolerance include lactose-reduced diet and enzyme replacement. Documenting the response to multiple doses can guide rational dietary management; however, the clinical utility of this strategy has not been tested. This review summarizes the genetic basis, diagnosis, and treatment of lactose malabsorption and intolerance. PMID:24917953
Verghese, Bindhu; Lok, Mei; Wen, Jia; Alessandria, Valentina; Chen, Yi; Kathariou, Sophia; Knabel, Stephen
2011-01-01
Different strains of Listeria monocytogenes are well known to persist in individual food processing plants and to contaminate foods for many years; however, the specific genotypic and phenotypic mechanisms responsible for persistence of these unique strains remain largely unknown. Based on sequences in comK prophage junction fragments, different strains of epidemic clones (ECs), which included ECII, ECIII, and ECV, were identified and shown to be specific to individual meat and poultry processing plants. The comK prophage-containing strains showed significantly higher cell densities after incubation at 30°C for 48 h on meat and poultry food-conditioning films than did strains lacking the comK prophage (P < 0.05). Overall, the type of strain, the type of conditioning film, and the interaction between the two were all highly significant (P < 0.001). Recombination analysis indicated that the comK prophage junction fragments in these strains had evolved due to extensive recombination. Based on the results of the present study, we propose a novel model in which the concept of defective comK prophage was replaced with the rapid adaptation island (RAI). Genes within the RAI were recharacterized as “adaptons,” as these genes may allow L. monocytogenes to rapidly adapt to different food processing facilities and foods. If confirmed, the model presented would help explain Listeria's rapid niche adaptation, biofilm formation, persistence, and subsequent transmission to foods. Also, comK prophage junction fragment sequences may permit accurate tracking of persistent strains back to and within individual food processing operations and thus allow the design of more effective intervention strategies to reduce contamination and enhance food safety. PMID:21441318
Verghese, Bindhu; Lok, Mei; Wen, Jia; Alessandria, Valentina; Chen, Yi; Kathariou, Sophia; Knabel, Stephen
2011-05-01
Different strains of Listeria monocytogenes are well known to persist in individual food processing plants and to contaminate foods for many years; however, the specific genotypic and phenotypic mechanisms responsible for persistence of these unique strains remain largely unknown. Based on sequences in comK prophage junction fragments, different strains of epidemic clones (ECs), which included ECII, ECIII, and ECV, were identified and shown to be specific to individual meat and poultry processing plants. The comK prophage-containing strains showed significantly higher cell densities after incubation at 30°C for 48 h on meat and poultry food-conditioning films than did strains lacking the comK prophage (P < 0.05). Overall, the type of strain, the type of conditioning film, and the interaction between the two were all highly significant (P < 0.001). Recombination analysis indicated that the comK prophage junction fragments in these strains had evolved due to extensive recombination. Based on the results of the present study, we propose a novel model in which the concept of defective comK prophage was replaced with the rapid adaptation island (RAI). Genes within the RAI were recharacterized as "adaptons," as these genes may allow L. monocytogenes to rapidly adapt to different food processing facilities and foods. If confirmed, the model presented would help explain Listeria's rapid niche adaptation, biofilm formation, persistence, and subsequent transmission to foods. Also, comK prophage junction fragment sequences may permit accurate tracking of persistent strains back to and within individual food processing operations and thus allow the design of more effective intervention strategies to reduce contamination and enhance food safety.
The gourmet ape: evolution and human food preferences.
Krebs, John R
2009-09-01
This review explores the relation between evolution, ecology, and culture in determining human food preferences. The basic physiology and morphology of Homo sapiens sets boundaries to our eating habits, but within these boundaries human food preferences are remarkably varied, both within and between populations. This does not mean that variation is entirely cultural or learned, because genes and culture may coevolve to determine variation in dietary habits. This coevolution has been well elucidated in some cases, such as lactose tolerance (lactase persistence) in adults, but is less well understood in others, such as in favism in the Mediterranean and other regions. Genetic variation in bitter taste sensitivity has been well documented, and it affects food preferences (eg, avoidance of cruciferous vegetables). The selective advantage of this variation is not clear. In African populations, there is an association between insensitivity to bitter taste and the prevalence of malaria, which suggests that insensitivity may have been selected for in regions in which eating bitter plants would confer some protection against malaria. Another, more general, hypothesis is that variation in bitter taste sensitivity has coevolved with the use of spices in cooking, which, in turn, is thought to be a cultural tradition that reduces the dangers of microbial contamination of food. Our evolutionary heritage of food preferences and eating habits leaves us mismatched with the food environments we have created, which leads to problems such as obesity and type 2 diabetes.
The evolution of dual meat and milk cattle husbandry in Linearbandkeramik societies
Kovačiková, Lenka; Bréhard, Stéphanie; Guthmann, Emilie; Vostrovská, Ivana; Nohálová, Hana; Arbogast, Rose-Marie; Domboróczki, László; Pechtl, Joachim; Anders, Alexander; Marciniak, Arkadiusz; Tresset, Anne; Vigne, Jean-Denis
2017-01-01
Cattle dominate archaeozoological assemblages from the north-central Europe between the sixth and fifth millennium BC and are frequently considered as exclusively used for their meat. Dairy products may have played a greater role than previously believed. Selective pressure on the lactase persistence mutation has been modelled to have begun between 6000 and 4000 years ago in central Europe. The discovery of milk lipids in late sixth millennium ceramic sieves in Poland may reflect an isolated regional peculiarity for cheese making or may signify more generalized milk exploitation in north-central Europe during the Early Neolithic. To investigate these issues, we analysed the mortality profiles based on age-at-death analysis of cattle tooth eruption, wear and replacement from 19 archaeological sites of the Linearbandkeramik (LBK) culture (sixth to fifth millennium BC). The results indicate that cattle husbandry was similar across time and space in the LBK culture with a degree of specialization for meat exploitation in some areas. Statistical comparison with reference age-at-death profiles indicate that mixed husbandry (milk and meat) was practised, with mature animals being kept. The analysis provides a unique insight into LBK cattle husbandry and how it evolved in later cultures in central and western Europe. It also opens a new perspective on how and why the Neolithic way of life developed through continental Europe and how dairy products became a part of the human diet. PMID:28768891
[Lactose malabsorption and -intolerance - who will benefit from a lactose-reduced diet?
Malham, Mikkel; Olin, Anne Bille; Pærregaard, Anders
2017-02-06
During the last decade, lactose-free diets have become increasingly popular in the general population, either isolated or as a part of a cow's milk-free diet. However, health-related benefits from a lactose-free diet are only documented for individuals with clinical lactose intolerance due to decreased intestinal lactase activity and subsequent lactose malabsorption. In this paper we summarize the current knowledge of lactose intolerance regarding diagnostic procedures and treatment.
Lundberg, Å; Nyman, A-K; Aspán, A; Börjesson, S; Unnerstad, H Ericsson; Waller, K Persson
2016-03-01
Udder infections with Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis are common causes of bovine mastitis. To study these pathogens in early lactation, a 12-mo longitudinal, observational study was carried out in 13 herds with suboptimal udder health. The aims of the study were to investigate the occurrence of these pathogens and to identify if presence of the 3 pathogens, and of genotypes within the pathogens, differed with respect to herd, season, and parity. Quarter milk samples, collected at calving and 4 d in milk (DIM), were cultured for the 3 pathogens. Genotyping of staphylococcal and streptococcal isolates was performed using spa typing and pulsed-field gel electrophoresis, respectively. For each of the 3 pathogens, cows with an udder infection at calving or 4 DIM were allocated to 1 of 4 infection types: cleared (pathogen present only at calving), persistent (pathogen present in the same quarter at calving and 4 DIM), new (pathogen present only at 4 DIM), or cleared/new (pathogen present in 1 quarter at calving and in another quarter at 4 DIM). Associations between season or parity and overall occurrence of pathogens or infection types were determined using univariable mixed-effect logistic-regression models and the Fisher's exact test, respectively. The most commonly occurring pathogen was Staph. aureus, followed by Strep. dysgalactiae and Strep. uberis. Persistent infections were the most common infection type among Staph. aureus-infected cows, whereas cleared infections were the most common among Strep. dysgalactiae- and Strep. uberis-positive cows. The proportion of cows with persistent Staph. aureus infections and the proportion of cows having a Strep. uberis infection at calving or 4 DIM were higher in the multiparous cows than in primiparous cows. Infections with Strep. dysgalactiae were less common during the early housing season than during the late housing or pasture seasons, whereas persistent Strep. uberis infections were less common during the pasture season than during the late housing season. The relative occurrence of the 3 pathogens, infection types of each pathogen, and genotype diversity of each pathogen throughout the year or in different seasons and parities varied among the herds, indicating that underlying factors predisposing for udder infections at calving differ between herds. Genotyping of bacterial isolates gave important insight into how such infection patterns differed within and between herds. These findings emphasize the need to choose preventive strategies for each individual herd. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
High incidence of Celiac Disease in a Long-term Study of Adolescents With Susceptibility Genotypes
Liu, Edwin; Dong, Fran; Barón, Anna E.; Taki, Iman; Norris, Jill M.; Frohnert, Brigitte I; Hoffenberg, Edward J; Rewers, Marian
2017-01-01
Background & Aims Little is known about the incidence of celiac disease in the general population of children in the United States. We aimed to estimate the cumulative incidence of celiac disease in adolescents born in the Denver metropolitan area. Methods We collected data on HLA-DR, DQ genotypes of 31,766 infants, born from 1993 through 2004 at St. Joseph’s Hospital in Denver, from the Diabetes Autoimmunity Study in the Young. Subjects with susceptibility genotypes for celiac disease and type 1 diabetes were followed for up to 20 years for development of tissue transglutaminase autoantibodies (tTGA). Outcomes were the development of celiac disease autoimmunity (CDA) or celiac disease. CDA was defined as persistence of tTGA for at least 3 months or development of celiac disease. Celiac disease was defined based on detection of Marsh 2 or greater lesions in biopsies or persistent high levels of tTGA. For each genotype, the cumulative incidence of CDA and celiac disease were determined. To estimate the cumulative incidence in the Denver general population, outcomes by each genotype were weighted according to the frequency of each of these genotypes in the general population. Results Of 1339 subjects followed, 66 developed CDA and met criteria for celiac disease and 46 developed only CDA. Seropositivity for tTGA resolved spontaneously, without treatment, in 21 of the 46 subjects with only CDA (46%). The estimated cumulative incidence for CDA in the Denver general population at 5, 10, and 15 years of age was 2.4%, 4.3%, and 5.1% respectively; incidence values for celiac disease were 1.6%, 2.8%, and 3.1%, respectively. Conclusions In a 20-year prospective study of 1339 children with genetic risk factors for celiac disease, we found the cumulative incidence of CDA and celiac disease to be high within the first 10 years. Although more than 5% of children may experience a period of CDA, not all develop celiac disease or require gluten-free diets. PMID:28188747
High Incidence of Celiac Disease in a Long-term Study of Adolescents With Susceptibility Genotypes.
Liu, Edwin; Dong, Fran; Barón, Anna E; Taki, Iman; Norris, Jill M; Frohnert, Brigitte I; Hoffenberg, Edward J; Rewers, Marian
2017-05-01
Little is known about the incidence of celiac disease in the general population of children in the United States. We aimed to estimate the cumulative incidence of celiac disease in adolescents born in the Denver metropolitan area. We collected data on HLA-DR, DQ genotypes of 31,766 infants, born from 1993 through 2004 at St. Joseph's Hospital in Denver, from the Diabetes Autoimmunity Study in the Young. Subjects with susceptibility genotypes for celiac disease and type 1 diabetes were followed up for up to 20 years for development of tissue transglutaminase autoantibodies (tTGA). Outcomes were the development of celiac disease autoimmunity (CDA) or celiac disease. CDA was defined as persistence of tTGA for at least 3 months or development of celiac disease. Celiac disease was defined based on detection of Marsh 2 or greater lesions in biopsy specimens or persistent high levels of tTGA. For each genotype, the cumulative incidence of CDA and celiac disease were determined. To estimate the cumulative incidence in the Denver general population, outcomes by each genotype were weighted according to the frequency of each of these genotypes in the general population. Of 1339 subjects followed up, 66 developed CDA and met criteria for celiac disease and 46 developed only CDA. Seropositivity for tTGA resolved spontaneously, without treatment, in 21 of the 46 subjects with only CDA (46%). The estimated cumulative incidence for CDA in the Denver general population at 5, 10, and 15 years of age was 2.4%, 4.3%, and 5.1%, respectively, and incidence values for celiac disease were 1.6%, 2.8%, and 3.1%, respectively. In a 20-year prospective study of 1339 children with genetic risk factors for celiac disease, we found the cumulative incidence of CDA and celiac disease to be high within the first 10 years. Although more than 5% of children may experience a period of CDA, not all children develop celiac disease or require gluten-free diets. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.
Szénási, Ágnes; Pálinkás, Zoltán; Zalai, Mihály; Schmitz, Oswald J; Balog, Adalbert
2014-06-17
There is concern that genetically modified (GM) plants may have adverse affects on the arthropod biodiversity comprising agricultural landscapes. The present study report on a two year field experimental test of whether four different genotypic lines, some are novel with no previous field tests, of GM maize hybrids alter the structure of arthropod food webs that they harbour, relative to non-GM maize (control) that is widely used in agriculture. The different GM genotypes produced either Bt toxins, conferred glyphosate tolerance or a combination of the two traits. Quantitative food web analysis, based on short-term assessment assigning a total of 243,896 arthropod individuals collected from the treatments to their positions in food webs, revealed that complex and stable food webs persisted in each maize treatment. Moreover, food web structure remained relatively unchanged by the GM-genotype. The results suggest that at least in short-term period these particular GM maize genotypes will not have adverse effects on arthropod biota of agricultural landscapes.
Genital warts in children: what do they mean?
Jayasinghe, Y; Garland, S M
2006-01-01
Human papillomaviruses (HPVs) are a diverse family of viruses, of which 30–40 genotypes specifically infect the genital tract. Genital HPVs are largely transmitted sexually, with most infections being asymptomatic and transient. In contrast, persistent infection with oncogenic genotypes in a minority is a strong risk factor, for subsequent development of high grade dysplasia, the precursor lesion to cervical neoplasia, which generally occurs after a long latency period. It is unknown whether there is a disease correlate in children chronically infected with oncogenic HPVs. Low risk HPV genotypes 6 and 11 are the primary cause of condylomata acuminata, although in children non‐genital genotypes are also found in a proportion, with the mode of transmission being either perinatal, horizontal, or sexual. The finding of asymptomatic HPV DNA in children, and correlation with live virus, infectivity, or disease is unclear. Long term follow up for children with anogenital warts is recommended, although there are no longitudinal studies available to clarify whether they are at risk of developing carcinoma in young adulthood. PMID:16670117
A third genotype of the human parvovirus PARV4 in sub-Saharan Africa.
Simmonds, Peter; Douglas, Jill; Bestetti, Giovanna; Longhi, Erika; Antinori, Spinello; Parravicini, Carlo; Corbellino, Mario
2008-09-01
PARV4 is a recently discovered human parvovirus widely distributed in injecting drug users in the USA and Europe, particularly in those co-infected with human immunodeficiency virus (HIV). Like parvovirus B19, PARV4 persists in previously exposed individuals. In bone marrow and lymphoid tissue, PARV4 sequences were detected in two sub-Saharan African study subjects with AIDS but without a reported history of parenteral exposure and who were uninfected with hepatitis C virus. PARV4 variants infecting these subjects were phylogenetically distinct from genotypes 1 and 2 (formerly PARV5) that were reported previously. Analysis of near-complete genome sequences demonstrated that they should be classified as a third (equidistant) PARV4 genotype. The availability of a further near-complete genome sequence of this novel genotype facilitated identification of conserved novel open reading frames embedded in the ORF2 coding sequence; one encoded a putative protein with identifiable homology to SAT proteins of members of the genus Parvovirus.
Zedan, Magdy; Settin, Ahmed; Farag, Mohammad K; El-Bayoumi, Mohammed; El Regal, Mohammed Ezz; El Baz, Rizk; Osman, Engy
2008-01-01
Tumor necrosis factor (TNF) alpha-308 and interleukin (IL)-10(-1082) have potent inflammatory responses in the process of airway inflammation in asthma. The purpose of this study was to check for association of polymorphisms related to cytokine genes with susceptibility and severity of bronchial asthma in Egyptian children. Blood samples of 69 asthmatic children receiving treatment and follow-up at the Allergy and Respiratory Medicine Unit, Mansoura University Children Hospital, Mansoura, Egypt, were subjected to DNA extraction and amplification using polymerase chain reaction with sequence-specific primers for detection of single nucleotide polymorphisms in the promoter regions of cytokine genes TNF-alpha(-308(G-->A)), IL-10(-1082(G-->A)). Compared with normal controls, Egyptian asthmatic children showed a significant higher frequency of IL-10(-1082) G/G homozygosity genotype (p < 0.001; odds ratio [OR] = 7) with lower frequency of G/A heterozygosity genotype among cases. This finding also was detected in cases with persistent asthma and eczema. These cases showed significant lower frequency of TNF-alpha-308 G/A heterozygosity (p < 0.05; OR = 0.44). Also, male cases, cases with positive family history, and those patients with persistent types of asthma showed a higher frequency of TNF-alpha-308 G/G homozygosity. IL-10(-1082(G-->A)) G/G and TNF-alpha-308(G-->A) G/G may be a contributing factor in susceptibility as well as severity of asthma among Egyptian children. Separate studies should be specified relating these cytokine genotypes to response to various modalities in asthma therapy. This study reports that IL-10(-1082(G-->A)) G/G and TNF-alpha-308(G-->A) G/G genotypes may be contributing factors in susceptibility as well as in severity of asthma among Egyptian children. Separate studies may be specified relating these cytokine genotypes to response to various modalities in asthma therapy.
López-Mejías, Raquel; Genre, Fernanda; Remuzgo-Martínez, Sara; Sevilla Pérez, Belen; Castañeda, Santos; Llorca, Javier; Ortego-Centeno, Norberto; Ubilla, Begoña; Mijares, Verónica; Pina, Trinitario; Calvo-Río, Vanesa; Miranda-Filloy, Jose A; Navas Parejo, Antonio; Argila, Diego; Sánchez-Pérez, Javier; Rubio, Esteban; Luque, Manuel León; Blanco-Madrigal, Juan María; Galíndez-Aguirregoikoa, Eva; Martín, Javier; Blanco, Ricardo; González-Gay, Miguel A
2016-01-01
Data from a small series suggested that the Interleukin 1 beta (IL1ß) rs16944 polymorphism may be associated with severe renal involvement and persistent renal damage (renal sequelae) in Henoch-Schönlein purpura (HSP). To confirm this association, we assessed the largest cohort of Caucasian HSP patients ever considered for genetic studies. 338 Spanish HSP patients and 635 sex and ethnically matched controls were recruited in this study. All patients were required to have had at least 6 months' follow-up. Patients and controls were genotyped for IL1β rs16944 by TaqMan genotyping assay. No differences between IL1β rs16944 genotype or allele frequencies were found either in the case/control study or when HSP patients were stratified according to the age at disease onset, presence of nephritis or gastrointestinal manifestations. Nevertheless, 4 (25%) of the 16 HSP patients who developed severe renal manifestations carried the TT genotype versus 29 (9%) of 322 who did not develop this complication (p=0.01, OR=5.48, 95% CI: 1.01-28.10). Accordingly, patients carrying the mutant T allele had an increased risk of developing severe nephropathy (p=0.016, OR=2.35, 95% CI: 1.09-5.07). Additionally, a significant increase of the TT genotype was observed in patients with persistent renal damage when compared with those patients without this complication (25% versus 8.6%, respectively; p=0.0035, OR=4.90, 95% CI: 1.26- 18.51). Moreover, renal sequelae were more common in patients carrying the mutant T allele (p=0.0076, OR=2.20, 95% CI: 1.17-4.14). Our results support that the IL1ß rs16944 polymorphism may be a potential marker of severe renal manifestations and renal sequelae in HSP.
Marozik, Pavel; Mosse, Irma; Alekna, Vidmantas; Rudenko, Ema; Tamulaitienė, Marija; Ramanau, Heorhi; Strazdienė, Vaidilė; Samokhovec, Volha; Ameliyanovich, Maxim; Byshnev, Nikita; Gonchar, Alexander; Kundas, Liubov; Zhur, Krystsina
2013-01-01
BACKGROUND AND OBJECTIVE. Variation of osteoporosis in the population is the result of an interaction between the genotype and the environment, and the genetic causes of osteoporosis are being widely investigated. The aim of this study was to analyze the association between the polymorphisms of the vitamin D receptor (VDR), type I collagen (COL1A1), and lactase (LCT) genes and severe postmenopausal osteoporosis as well as bone mineral density (BMD). MATERIAL AND METHODS. A total of 54 women with severe postmenopausal osteoporosis and 77 controls (mean age, 58.3 years [SD, 6.2] and 56.7 years [SD, 7.42], respectively) were included into the study. The subjects were recruited at the City Center for Osteoporosis Prevention (Minsk, Belarus). Dual-energy x-ray absorptiometry was used to measure bone mineral density at the lumbar spine and the femoral neck. Severe osteoporosis was diagnosed in the women with the clinical diagnosis of postmenopausal osteoporosis and at least 1 fragility fracture. The control group included women without osteoporosis. Polymorphic sites in osteoporosis predisposition genes (ApaI, BsmI, TaqI, and Cdx2 of the VDR gene, G2046T of the COL1A1 gene, and T-13910C of the LCT gene) were determined using the polymerase chain reaction on the deoxyribonucleic acid isolated from dried bloodspots. RESULTS. The data showed that the ApaI and BsmI polymorphisms of the VDR gene and T- 13910C of the LCT gene were associated with severe postmenopausal osteoporosis in the analyzed Belarusian women (P<0.01). A statistically significant positive correlation between the VDR risk genotypes ApaI and TaqI and bone mineral density was found (P<0.05). CONCLUSIONS. The findings of this study suggest that at least the ApaI and BsmI polymorphisms of the VDR gene and T-13910C of the LCT gene are associated with the risk of postmenopausal osteoporosis in our sample of the Belarusian women.
Molecular Epidemiology of Glanders, Pakistan
Hornstra, Heidie; Pearson, Talima; Georgia, Shalamar; Liguori, Andrew; Dale, Julia; Price, Erin; O’Neill, Matthew; DeShazer, David; Muhammad, Ghulam; Saqib, Muhammad; Naureen, Abeera
2009-01-01
We collected epidemiologic and molecular data from Burkholderia mallei isolates from equines in Punjab, Pakistan from 1999 through 2007. We show that recent outbreaks are genetically distinct from available whole genome sequences and that these genotypes are persistent and ubiquitous in Punjab, probably due to human-mediated movement of equines. PMID:19961695
Ivancic-Jelecki, Jelena; Baricevic, Marijana; Santak, Maja; Harcet, Matija; Tešović, Goran; Marusic Della Marina, Branka; Forcic, Dubravko
2013-07-01
Measles virus (MV) strains derived from patients with subacute sclerosing panencephalitis (SSPE), SSPE strains, possess numerous mutations when compared to viruses belonging to the same genotype and circulating in similar time period. Although many SSPE strains have been extensively characterized, none of them belongs to D4 genotype which currently predominates in Europe where it has caused a number of recent outbreaks/epidemics. We sequenced an MV derived from a patient with long-term SSPE; the virus was named MVs/Zagreb.CRO/30.06[D4] (SSPE). Initial genetic analysis showed that it belongs to D4 genotype. The sequences of genes encoding matrix and fusion proteins indicate premature protein terminations. Putative hemagglutin (H) protein is lengthened for 20 amino acids, which is the longest H protein elongation so far found in SSPE viruses. Nucleotides 1421 A, 1422 G, 1507 C and 1542 C in nucleoprotein gene open reading frame seem to be specific for this D4 strain, differentiating it from other D4 non-SSPE strains. Besides, a unique mutation at position 543 of H protein was found, histidine instead of tyrosine. As persistent MV infections are initially established by "normal" wild-type MV strains, the presented comparative analyses describe alterations that could be involved in the maintenance of persistent infection, disease development and progression. Copyright © 2013 Elsevier B.V. All rights reserved.
Evans, Suzanna M; Vergés, Adriana; Poore, Alistair G B
2017-01-01
Seagrasses that are predominantly clonal often have low levels of genetic variation within populations and predicting their response to changing conditions requires an understanding of whether genetic variation confers increased resistance to environmental stressors. A higher level of genetic diversity is assumed to benefit threatened species due to the increased likelihood of those populations having genotypes that can persist under environmental change. To test this idea, we conducted an in situ shading experiment with six geographically distinct meadows of the threatened seagrass Posidonia australis that vary in genetic diversity. Different genotypes within meadows varied widely in their physiological and growth responses to reduced light during a simulated short-term turbidity event. The majority of meadows were resistant to the sudden reduction in light availability, but a small subset of meadows with low genotypic diversity were particularly vulnerable to the early effects of shading, showing substantially reduced growth rates after only 3 weeks. Using the photosynthetic performance (maximum quantum yield) of known genotypes, we simulated meadows of varying genetic diversity to show that higher diversity can increase meadow resilience to stress by ensuring a high probability of including a high-performing genotype. These results support the hypothesis that complementarity among genotypes enhances the adaptive capacity of a population, and have significant implications for the conservation of declining P. australis meadows close to the species range edge on the east coast of Australia, where the genotypic diversity is low.
Evans, Suzanna M.; Vergés, Adriana; Poore, Alistair G. B.
2017-01-01
Seagrasses that are predominantly clonal often have low levels of genetic variation within populations and predicting their response to changing conditions requires an understanding of whether genetic variation confers increased resistance to environmental stressors. A higher level of genetic diversity is assumed to benefit threatened species due to the increased likelihood of those populations having genotypes that can persist under environmental change. To test this idea, we conducted an in situ shading experiment with six geographically distinct meadows of the threatened seagrass Posidonia australis that vary in genetic diversity. Different genotypes within meadows varied widely in their physiological and growth responses to reduced light during a simulated short-term turbidity event. The majority of meadows were resistant to the sudden reduction in light availability, but a small subset of meadows with low genotypic diversity were particularly vulnerable to the early effects of shading, showing substantially reduced growth rates after only 3 weeks. Using the photosynthetic performance (maximum quantum yield) of known genotypes, we simulated meadows of varying genetic diversity to show that higher diversity can increase meadow resilience to stress by ensuring a high probability of including a high-performing genotype. These results support the hypothesis that complementarity among genotypes enhances the adaptive capacity of a population, and have significant implications for the conservation of declining P. australis meadows close to the species range edge on the east coast of Australia, where the genotypic diversity is low. PMID:28855915
Pathogenesis of duck circovirus genotype 1 in experimentally infected Pekin ducks.
Hong, Y-T; Kang, M; Jang, H-K
2018-05-17
Ducks infected with duck circovirus (DuCV) exhibit feathering disorder, growth retardation, and low body weight. The virus can induce immunosuppression and increase rates of infection caused by other pathogens. The purpose of the present study was to investigate the pathogenesis of DuCV in experimentally infected Pekin ducks. At postmortem examination, gross lesions were observed in the immune organs including bursa of Fabricius (BF), thymus, and spleen. Hemorrhage, lymphocytic depletion, necrosis, and degeneration were observed in the bursal tissues by histological examination. The TUNEL assay was performed with bursal tissue. There was a significant difference of the apoptosis rate between the negative and DuCV-infected ducks. The earliest time point for detection of DuCV DNA in sera, cloacal swabs, and organs was 1 wk post-infection (WPI). Viral shedding was persistent and detectable at the end of the experiment (10 WPI). The findings provide evidence that horizontal transmission and persistent infection are the characteristics of DuCV. The organ with the highest mean viral load was the spleen, followed by BF, cecal tonsil, lung, thymus, liver, and kidney. We successfully established an experimental DuCV genotype 1 (DuCV-1) infection in Pekin ducks and demonstrated the pathogenicity and persistence of DuCV-1. In conclusion, DuCV-1 caused extensive damage to the immune organs that may have resulted in immunosuppression. Pathobiological characteristics of DuCV-1 include systemic infection, persistent infection, and horizontal transmission. These features allow DuCV-1 to circulate more easily in farms and increase the susceptibility of ducks to other diseases.
Abendaño, Naiara; Sevilla, Iker A; Prieto, José Miguel; Garrido, Joseba M; Juste, Ramon A; Alonso-Hearn, Marta
2013-05-03
Assessment of the virulence of isolates of Mycobacterium avium subsp. paratuberculosis (Map) exhibiting distinct genotypes and isolated from different hosts may help to clarify the degree to which clinical manifestations of the disease in cattle can be attributed to bacterial or to host factors. The objective of this study was to test the ability of 10 isolates of Map representing distinct genotypes and isolated from domestic (cattle, sheep, and goat), and wildlife animal species (fallow deer, deer, wild boar, and bison) to enter and grow in bovine macrophages. The isolates were previously typed using IS1311 PCR followed by restriction endonuclease analysis into types C, S or B. Intracellular growth of the isolates in a bovine macrophage-like cell line (BoMac) and in primary bovine monocyte-derived macrophages (MDM) was evaluated by quantification of CFU numbers in the initial inoculum and inside of the host cells at 2h and 7 d p.i. using an automatic liquid culture system (Bactec MGIT 960). Individual data illustrated that growth was less variable in BoMac than in MDM cells. All the isolates from goat and sheep hosts persisted within BoMac cells in lower CFU numbers than the other tested isolates after 7 days of infection regardless of genotype. In addition, BoMac cells exhibited differential inflammatory, apoptotic and destructive responses when infected with a bovine or an ovine isolate; which correlated with the differential survival of these strains within BoMac cells. Our results indicated that the survival of the tested Map isolates within bovine macrophages is associated with the specific host from which the isolates were initially isolated. Copyright © 2013 Elsevier B.V. All rights reserved.
Lactose malabsorption and intolerance: What should be the best clinical management?
Usai-Satta, Paolo; Scarpa, Mariella; Oppia, Francesco; Cabras, Francesco
2012-06-06
Lactose malabsorption (LM) is the incomplete hydrolysis of lactose due to lactase deficiency, which may occur as a primary disorder or secondary to other intestinal diseases. Primary adult-type hypolactasia is an autosomal recessive condition resulting from the physiological decline of lactase activity. Different methods have been used to diagnose LM. Lactose breath test represents the most reliable technique. A recent consensus conference has proposed the more physiological dosage of 25 g of lactose and a standardized procedure for breath testing. Recently a new genetic test, based on C/T13910 polymorphism, has been proposed for the diagnosis of adult-type hypolactasia, complementing the role of breath testing. LM represents a well-known cause of abdominal symptoms although only some lactose malabsorbers are also intolerants. Diagnosing lactose intolerance is not straightforward. Many non-malabsorber subjects diagnose themselves as being lactose intolerant. Blind lactose challenge studies should be recommended to obtain objective results. Besides several studies indicate that subjects with lactose intolerance can ingest up to 15 g of lactose with no or minor symptoms. Therefore a therapeutic strategy consists of a lactose restricted diet avoiding the nutritional disadvantages of reduced calcium and vitamin intake.Various pharmacological options are also available. Unfortunately there is insufficient evidence that these therapies are effective. Further double-blind studies are needed to demonstrate treatment effectiveness in lactose intolerance.
Lactose malabsorption and intolerance: What should be the best clinical management?
Usai-Satta, Paolo; Scarpa, Mariella; Oppia, Francesco; Cabras, Francesco
2012-01-01
Lactose malabsorption (LM) is the incomplete hydrolysis of lactose due to lactase deficiency, which may occur as a primary disorder or secondary to other intestinal diseases. Primary adult-type hypolactasia is an autosomal recessive condition resulting from the physiological decline of lactase activity. Different methods have been used to diagnose LM. Lactose breath test represents the most reliable technique. A recent consensus conference has proposed the more physiological dosage of 25 g of lactose and a standardized procedure for breath testing. Recently a new genetic test, based on C/T13910 polymorphism, has been proposed for the diagnosis of adult-type hypolactasia, complementing the role of breath testing. LM represents a well-known cause of abdominal symptoms although only some lactose malabsorbers are also intolerants. Diagnosing lactose intolerance is not straightforward. Many non-malabsorber subjects diagnose themselves as being lactose intolerant. Blind lactose challenge studies should be recommended to obtain objective results. Besides several studies indicate that subjects with lactose intolerance can ingest up to 15 g of lactose with no or minor symptoms. Therefore a therapeutic strategy consists of a lactose restricted diet avoiding the nutritional disadvantages of reduced calcium and vitamin intake.Various pharmacological options are also available. Unfortunately there is insufficient evidence that these therapies are effective. Further double-blind studies are needed to demonstrate treatment effectiveness in lactose intolerance. PMID:22966480
NASA Astrophysics Data System (ADS)
Miyake, M.; Yamasaki, M.; Hazama, A.; Ijiri, K.; Shimizu, T.
It is important to assure whether digestive system can develop normally in neonates during spaceflight. Because the small intestine changes its function and structure drastically around weaning known as redifferentiation. Lactase expression declines and sucrase increases in small intestine for digestion of solid food before weaning. In this paper, we compared this enzyme transition and structural development of small intestine in neonatal rats after spaceflight. To find digestive genes differentially expressed in fight rats, DNA membrane macroarray was also used. Eight-day old rats were loaded to Space Shuttle Columbia, and housed in the animal facility for 16 days in space (STS-90, Neurolab mission). Two control groups (AGC; asynchronous ground control and VIV; vivarium) against flight group (FLT) were prepared. There was no difference in structure (crypt depth) and cell differentiation of epithelium between FLT and AGC by immunohistochemical analysis. We found that the amount of sucrase mRNA compared to lactase was decreased in FLT by RT-PCR. It reflected the enzyme transition was inhibited. Increase of 5 genes (APO A-I, APO A-IV, ACE, aFABP and aminopeptidase M) and decrease of carboxypeptidase-D were detected in FLT using macroarray. We think nutrition differences (less nourishment and late weaning) during spaceflight may cause inhibition of enzyme transition at least partly. The weightlessness might contribute to the inhibition through behavioral change.
Toll like receptor-4 gene polymorphisms in patients with solitary cysticercus granuloma.
Singh, Akhilesh; Garg, Ravindra Kumar; Jain, Amita; Malhotra, Hardeep Singh; Prakash, Shantanu; Verma, Rajesh; Sharma, Praveen Kumar
2015-08-15
Solitary cysticercus granuloma (SCG) of the brain is the most common type of neurocysticercosis in India. In this study, we evaluated TLR4 polymorphisms in patients with SCG. One-hundred-forty-three patients with SCG and 134 controls were enrolled. Assessment for TLR4 Asp299Gly and Thr399Ile polymorphism was done. TLR4 genotype was determined by PCR-sequencing chain termination method. The patients were followed for 6 months. Asp/Gly (P=0.024) and Thr/Ile (P=0.004) genotypes were significantly associated with the SCG. The Gly (Asp/Gly plus Gly/Gly) genotype (P=0.025) and Ile (Thr/Ile plus Ile/Ile) genotype (P=0.008) were significantly associated with the SCG. Gly/Gly and Ile/Ile genotypes were not significantly associated with SCG (P=0.767 for Gly/Gly, P=0.936 for Ile/Ile). At 6 months, TLR4 299Asp/Gly (P=0.02) and 399Ile/Thr (P=0.023) polymorphisms were significantly associated with the calcification or persistence of SCG. TLR4 polymorphisms are associated with the susceptibility to infection with SCG. Copyright © 2015 Elsevier B.V. All rights reserved.
Szilagyi, Andrew; Galiatsatos, Polymnia; Xue, Xiaoqing
2016-07-13
Relationships between inflammatory bowel disease and lactose containing foods remain controversial and poorly defined regarding symptoms, nutritional outcomes, and epidemiologic associations for lactose maldigestion. A literature review was performed using Pub Med, Cochrane library and individual references, to extract data on lactose maldigestion prevalence in inflammatory bowel diseases. A meta-analysis was done using selected articles, to determine odds ratios of maldigestion. Information was collected about symptoms, impact on pattern of dairy food consumption, as well as the effects of dairy foods on the course of inflammatory bowel diseases. A total of 1022 articles were evaluated, 35 articles were retained and 5 studies were added from review articles. Of these 17 were included in meta-analysis which showed overall increased lactose maldigestion in both diseases. However increased risk on sub analysis was only found in Crohn's in patients with small bowel involvement. Nine additional studies were reviewed for symptoms, with variable outcomes due to confounding between lactose intolerance and lactose maldigestion. Fourteen studies were evaluated for dairy food effects. There was a suggestion that dairy foods may protect against inflammatory bowel disease. Nutritional consequences of dairy restrictions might impact adversely on bone and colonic complications. Lactose maldigestion in inflammatory bowel disease is dependent on ethnic makeup of the population and usually not disease. No bias of increased disease prevalence was noted between lactase genotypes. Intolerance symptoms depend on several parameters besides lactose maldigestion. Dairy foods may decrease risks of inflammatory bowel disease. Dairy restrictions may adversely affect disease outcome.
Hepatitis C Virus Cell-Cell Transmission and Resistance to Direct-Acting Antiviral Agents
Heydmann, Laura; Barth, Heidi; Soulier, Eric; Habersetzer, François; Doffoël, Michel; Bukh, Jens; Patel, Arvind H.; Zeisel, Mirjam B.; Baumert, Thomas F.
2014-01-01
Hepatitis C virus (HCV) is transmitted between hepatocytes via classical cell entry but also uses direct cell-cell transfer to infect neighboring hepatocytes. Viral cell-cell transmission has been shown to play an important role in viral persistence allowing evasion from neutralizing antibodies. In contrast, the role of HCV cell-cell transmission for antiviral resistance is unknown. Aiming to address this question we investigated the phenotype of HCV strains exhibiting resistance to direct-acting antivirals (DAAs) in state-of-the-art model systems for cell-cell transmission and spread. Using HCV genotype 2 as a model virus, we show that cell-cell transmission is the main route of viral spread of DAA-resistant HCV. Cell-cell transmission of DAA-resistant viruses results in viral persistence and thus hampers viral eradication. We also show that blocking cell-cell transmission using host-targeting entry inhibitors (HTEIs) was highly effective in inhibiting viral dissemination of resistant genotype 2 viruses. Combining HTEIs with DAAs prevented antiviral resistance and led to rapid elimination of the virus in cell culture model. In conclusion, our work provides evidence that cell-cell transmission plays an important role in dissemination and maintenance of resistant variants in cell culture models. Blocking virus cell-cell transmission prevents emergence of drug resistance in persistent viral infection including resistance to HCV DAAs. PMID:24830295
Cortez, Valerie; Freiden, Pamela; Gu, Zhengming; Adderson, Elisabeth; Hayden, Randall; Schultz-Cherry, Stacey
2017-02-01
Human astroviruses are a major cause of pediatric gastroenteritis, especially in immunocompromised children. We conducted a retrospective study to demonstrate that diverse astrovirus genotypes can co-circulate in pediatric oncology patients. A subset of cases is associated with long-term virus shedding (range 17-183 days).
Bissett, Sara L; Godi, Anna; Jit, Mark; Beddows, Simon
2017-07-13
Human papillomavirus vaccines have demonstrated remarkable efficacy against persistent infection and disease associated with vaccine-incorporated genotypes and a degree of efficacy against some genetically related, non-vaccine-incorporated genotypes. The vaccines differ in the extent of cross-protection against these non-vaccine genotypes. Data supporting the role for neutralizing antibodies as a correlate or surrogate of cross-protection are lacking, as is a robust assessment of the seroconversion rates against these non-vaccine genotypes. We performed a systematic review and meta-analysis of available data on vaccine-induced neutralizing antibody seropositivity to non-vaccine incorporated HPV genotypes. Of 304 articles screened, 9 were included in the analysis representing ca. 700 individuals. The pooled estimate for seropositivity against HPV31 for the bivalent vaccine (86%; 95%CI 78-91%) was higher than that for the quadrivalent vaccine (61%; 39-79%; p=0.011). The pooled estimate for seropositivity against HPV45 for the bivalent vaccine (50%; 37-64%) was also higher than that for the quadrivalent vaccine (16%; 6-36%; p=0.007). Seropositivity against HPV33, HPV52 and HPV58 were similar between the vaccines. Mean seropositivity rates across non-vaccine genotypes were positively associated with the corresponding vaccine efficacy data reported from vaccine trials. These data improve our understanding of vaccine-induced functional antibody specificity against non-vaccine incorporated genotypes and may help to parameterize vaccine-impact models and improve patient management in a post-vaccine setting. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
Landscape Epidemiology of Tularemia Outbreaks in Sweden
Svensson, Kerstin; Bäck, Erik; Eliasson, Henrik; Berglund, Lennart; Granberg, Malin; Karlsson, Linda; Larsson, Pär; Forsman, Mats
2009-01-01
Summer outbreaks of tularemia that occurred from 1995 through 2005 in 2 locations in Sweden affected 441 persons. We performed an epidemiologic investigation of these outbreaks using a novel strategy, involving high-resolution genotyping of Francisella tularensis isolates obtained from 136 patients (using 18 genetic markers developed from 6 F. tularensis genome sequences) and interviews with the patients. Strong spatial associations were found between F. tularensis subpopulations and the places of disease transmission; infection by some subpopulations occurred within areas as small as 2 km2, indicating unidentified environmental point sources of tularemia. In both locations, disease clusters were associated with recreational areas beside water, and genetic subpopulations were present throughout the tularemia season and persisted over years. High-resolution genotyping in combination with patients’ statements about geographic places of disease transmission provided valuable indications of likely sources of infection and the causal genotypes during these tularemia outbreaks. PMID:19961673
Janssen, Paddy K C; van Schaik, R; Zwinderman, Aeilko H; Olivier, Berend; Waldinger, Marcel D
2014-06-01
Lifelong premature ejaculation (LPE) is characterized by persistent intravaginal ejaculation latency times (IELTs) of less than 1 min, and has been postulated as a neurobiological dysfunction related to diminished serotonergic neurotransmission with 5-HT₁A receptor hyperfunction and 5-HT₂C hypofunction. To investigate the relationship between 5-HT₁A receptor gene (HTR₁A)-C(1019)G promoter polymorphism and IELT in men with LPE. This polymorphism is known to increase 5-HT1A receptor expression. A prospective study was conducted in 54 Dutch Caucasian men with LPE. Baseline IELT during coitus was assessed by stopwatch over a 1-month period. All men were genotyped for HTR₁A gene polymorphism. Allele frequencies and genotypes of C and G variants of HTR₁A polymorphism were determined. Association between CC, CG, and GG genotypes and the IELT in men with LPE were investigated. IELT measured by stopwatch, HTR₁A polymorphism. In this cohort of men with LPE, the geometric mean IELT was 23.8 s. Of the 54 men, the CC, CG and GG genotype frequency for the C(1019)G polymorphism of the 5-HT₁A gene was 33%, 43% and 24%, respectively. The geometric mean IELT for the CC, CG and GG genotypes were 14.5, 27.7 and 36.0 s, respectively (p=0.019). Compared to GG and CG genotypes, men with CC genotype had a 250% and 190% shorter ejaculation time, respectively. HTR₁A gene polymorphism is associated with the IELT in men with LPE. Men with CC genotype have shorter IELTs than men with GG and CG genotypes. Copyright © 2014 Elsevier Inc. All rights reserved.
González-Hernández, Luz A; Flores-Miramontes, María G; Aguilar-Lemarroy, Adriana; Quintanilla-Peña, Krissya S; Martin-Amaya-Barajas, Fabiola L; Ramos-Solano, Moisés; Enciso Gómez, Luis F; Andrade-Villanueva, Jaime F; Jave-Suárez, Luis F
2018-04-01
The incidence of anal cancer has been rising, especially in HIV+ patients and has been associated with HPV infection. HIV+ patients are more at risk of HPV coinfection and are seven times more likely to have persistent HPV infection; moreover, HIV+ men have an increased risk of developing anal cancer compared to HIV+ women. The development of screening strategies for the detection of HPV in HIV+ men is of major importance; however, there is not enough information about the HPV genotypes and variants that are colonizing the anal epithelia of HIV+ men in diverse geographical regions. Therefore, this work was aimed at identifying HPV genotypes present in the anal epithelium of HIV+ men who have sex with men (MSM), with or without anal lesions (n = 75). For HPV genotyping, two approaches were performed: Linear Array HPV Genotyping Test and next-generation sequencing (NGS). In general, the six most frequent HPV genotypes found by Linear Array were HPV6, 62, 61, 81, 16 and 51. On the other hand, employing NGS, a total of 36 HPV genotypes belonging to both alpha and beta genera were found. The genotypes with the greatest number of reads, according to the diagnostic group, were: HPV81, 45, 6, 51 and 61 in MSM without anal lesions (WAIN); HPV6, 61, 70, 62 and 66 in MSM with atypical lesions (AAL); HPV6, 11, 66, 81 and 61 in MSM with anal intraepithelial neoplasia grade I (AIN I); and HPV16, 81, 58, 61 and 52 with AIN III. Additionally, a great diversity of L1 variants was observed, especially in genotypes HPV16, 58, 61, 52, 45 and 59.
Rotavirus Strain Trends During the Postlicensure Vaccine Era: United States, 2008–2013
Bowen, Michael D.; Mijatovic-Rustempasic, Slavica; Esona, Mathew D.; Teel, Elizabeth N.; Gautam, Rashi; Sturgeon, Michele; Azimi, Parvin H.; Baker, Carol J.; Bernstein, David I.; Boom, Julie A.; Chappell, James; Donauer, Stephanie; Edwards, Kathryn M.; Englund, Janet A.; Halasa, Natasha B.; Harrison, Christopher J.; Johnston, Samantha H.; Klein, Eileen J.; McNeal, Monica M.; Moffatt, Mary E.; Rench, Marcia A.; Sahni, Leila C.; Selvarangan, Rangaraj; Staat, Mary A.; Szilagyi, Peter G.; Weinberg, Geoffrey A.; Wikswo, Mary E.; Parashar, Umesh D.; Payne, Daniel C.
2016-01-01
Background Group A rotaviruses (RVA) are a significant cause of pediatric gastroenteritis worldwide. The New Vaccine Surveillance Network (NVSN) has conducted active surveillance for RVA at pediatric hospitals and emergency departments at 3–7 geographically diverse sites in the United States since 2006. Methods Over 6 consecutive years, from 2008 to 2013, 1523 samples from NVSN sites that were tested positive by a Rotaclone enzyme immunoassay were submitted to the Centers for Disease Control and Prevention for genotyping. Results In the 2009, 2010, and 2011 seasons, genotype G3P[8] was the predominant genotype throughout the network, with a 46%–84% prevalence. In the 2012 season, G12P[8] replaced G3P[8] as the most common genotype, with a 70% prevalence, and this trend persisted in 2013 (68.0% prevalence). Vaccine (RotaTeq; Rotarix) strains were detected in 0.6%–3.4% of genotyped samples each season. Uncommon and unusual strains (eg, G8P[4], G3P[24], G2P[8], G3P[4], G3P[6], G24P[14], G4P[6], and G9P[4]) were detected sporadically over the study period. Year, study site, and race were found to be significant predictors of genotype. Conclusions Continued active surveillance is needed to monitor RVA genotypes in the United States and to detect potential changes since vaccine licensure. PMID:27302190
Van Wyk, Marelize; Govender, Nelesh P.; Litvintseva, Anastasia P.
2014-01-01
Patients with cryptococcal meningitis in sub-Saharan Africa frequently relapse following treatment. The natural history and etiology of these recurrent episodes warrant investigation. Here, we used multilocus sequence typing (MLST) to compare the molecular genotypes of strains of Cryptococcus neoformans and Cryptococcus gattii isolated from serial episodes of cryptococcal meningitis that were separated by at least 110 days. The most common MLST genotypes among the isolates were the dominant global clinical genotypes (M5 and M4) of molecular type VNI, as well as the VNI genotypes apparently restricted to southern Africa. In addition, there was considerable genetic diversity among these South African isolates, as 15% of the patients had unique genotypes. Eleven percent of the patients were reinfected with a genetically different strain following their initial diagnosis and treatment. However, the majority of serial episodes (89%) were caused by strains with the same genotype as the original strain. These results indicate that serial episodes of cryptococcosis in South Africa are frequently associated with persistence or relapse of the original infection. Using a reference broth microdilution method, we found that the serial isolates of 11% of the patients infected with strains of C. neoformans var. grubii with identical genotypes exhibited ≥4-fold increases in the MICs to fluconazole. Therefore, these recurrent episodes may have been precipitated by inadequate induction or consolidation of antifungal treatment and occasionally may have been due to increased resistance to fluconazole, which may have developed during the chronic infection. PMID:24648562
Landman, W J M; Buter, G J; Dijkman, R; van Eck, J H H
2014-01-01
Escherichia coli colonies isolated from the bone marrow of fresh dead hens of laying flocks with the E. coli peritonitis syndrome (EPS) were genotyped using pulsed-field gel electrophoresis (PFGE). Typing is important from an epidemiological point of view and also if the use of autogenous (auto)vaccines is considered. Birds with EPS originated from one house of each of three layer farms and one broiler breeder farm. Farms were considered as separate epidemiological units. In total, six flocks were examined including two successive flocks of one layer farm and the broiler breeder farm. E. coli colonies (one per bird) from nine to 16 hens of each flock were genotyped. The clonality of E. coli within birds was studied using five colonies of each of nine to 14 birds per flock. E. coli genotypes, which totalled 15, differed between farms and flocks except for two successive layer flocks that shared three genotypes. One to five genotypes were found per flock with one or two genotypes dominating each outbreak. Within hens, E. coli bacteria were always clonal. Colonies of the same PFGE type always had the same multilocus sequence type. However, four PFGE types shared sequence type 95. Neither PFGE types nor multilocus sequence types were unambiguously related to avian pathogenic E. coli from EPS. In cases where persistence of E. coli strains associated with EPS is found to occur frequently, routine genotyping to select strains for autovaccines should be considered.
Detecting and Characterizing Genomic Signatures of Positive Selection in Global Populations
Liu, Xuanyao; Ong, Rick Twee-Hee; Pillai, Esakimuthu Nisha; Elzein, Abier M.; Small, Kerrin S.; Clark, Taane G.; Kwiatkowski, Dominic P.; Teo, Yik-Ying
2013-01-01
Natural selection is a significant force that shapes the architecture of the human genome and introduces diversity across global populations. The question of whether advantageous mutations have arisen in the human genome as a result of single or multiple mutation events remains unanswered except for the fact that there exist a handful of genes such as those that confer lactase persistence, affect skin pigmentation, or cause sickle cell anemia. We have developed a long-range-haplotype method for identifying genomic signatures of positive selection to complement existing methods, such as the integrated haplotype score (iHS) or cross-population extended haplotype homozygosity (XP-EHH), for locating signals across the entire allele frequency spectrum. Our method also locates the founder haplotypes that carry the advantageous variants and infers their corresponding population frequencies. This presents an opportunity to systematically interrogate the whole human genome whether a selection signal shared across different populations is the consequence of a single mutation process followed subsequently by gene flow between populations or of convergent evolution due to the occurrence of multiple independent mutation events either at the same variant or within the same gene. The application of our method to data from 14 populations across the world revealed that positive-selection events tend to cluster in populations of the same ancestry. Comparing the founder haplotypes for events that are present across different populations revealed that convergent evolution is a rare occurrence and that the majority of shared signals stem from the same evolutionary event. PMID:23731540
The evolution of dual meat and milk cattle husbandry in Linearbandkeramik societies.
Gillis, Rosalind E; Kovačiková, Lenka; Bréhard, Stéphanie; Guthmann, Emilie; Vostrovská, Ivana; Nohálová, Hana; Arbogast, Rose-Marie; Domboróczki, László; Pechtl, Joachim; Anders, Alexandra; Marciniak, Arkadiusz; Tresset, Anne; Vigne, Jean-Denis
2017-08-16
Cattle dominate archaeozoological assemblages from the north-central Europe between the sixth and fifth millennium BC and are frequently considered as exclusively used for their meat. Dairy products may have played a greater role than previously believed. Selective pressure on the lactase persistence mutation has been modelled to have begun between 6000 and 4000 years ago in central Europe. The discovery of milk lipids in late sixth millennium ceramic sieves in Poland may reflect an isolated regional peculiarity for cheese making or may signify more generalized milk exploitation in north-central Europe during the Early Neolithic. To investigate these issues, we analysed the mortality profiles based on age-at-death analysis of cattle tooth eruption, wear and replacement from 19 archaeological sites of the Linearbandkeramik (LBK) culture (sixth to fifth millennium BC). The results indicate that cattle husbandry was similar across time and space in the LBK culture with a degree of specialization for meat exploitation in some areas. Statistical comparison with reference age-at-death profiles indicate that mixed husbandry (milk and meat) was practised, with mature animals being kept. The analysis provides a unique insight into LBK cattle husbandry and how it evolved in later cultures in central and western Europe. It also opens a new perspective on how and why the Neolithic way of life developed through continental Europe and how dairy products became a part of the human diet. © 2017 The Authors.
Murray, Joseph; Burgess, Stephen; Zuccolo, Luisa; Hickman, Matthew; Gray, Ron; Lewis, Sarah J
2016-05-01
Heavy alcohol use during pregnancy can cause considerable developmental problems for children, but effects of light-moderate drinking are uncertain. This study examined possible effects of moderate drinking in pregnancy on children's conduct problems using a Mendelian randomisation design to improve causal inference. A prospective cohort study (ALSPAC) followed children from their mother's pregnancy to age 13 years. Analyses were based on 3,544 children whose mothers self-reported either not drinking alcohol during pregnancy or drinking up to six units per week without binge drinking. Children's conduct problem trajectories were classified as low risk, childhood-limited, adolescence-onset or early-onset-persistent, using six repeated measures of the Strengths and Difficulties Questionnaire between ages 4-13 years. Variants of alcohol-metabolising genes in children were used to create an instrumental variable for Mendelian randomisation analysis. Children's genotype scores were associated with early-onset-persistent conduct problems (OR = 1.29, 95% CI = 1.04-1.60, p = .020) if mothers drank moderately in pregnancy, but not if mothers abstained from drinking (OR = 0.94, CI = 0.72-1.25, p = .688). Children's genotype scores did not predict childhood-limited or adolescence-onset conduct problems. This quasi-experimental study suggests that moderate alcohol drinking in pregnancy contributes to increased risk for children's early-onset-persistent conduct problems, but not childhood-limited or adolescence-onset conduct problems. © 2015 The Authors. Journal of Child Psychology and Psychiatry published by John Wiley & Sons Ltd on behalf of Association for Child and Adolescent Mental Health.
Tsai, M-H; Chiu, C-Y; Shih, H-J; Liao, S-L; Hua, M-C; Huang, S-H; Yao, T-C; Lai, S-H; Huang, T-S; Yeh, K-W; Chen, L-C; Su, K-W; Lim, W-H; Chang, Y-J; Chiang, C-H; Huang, S-Y; Huang, J-L
2017-02-01
The study aimed to determine the long-term Staphylococcus aureus colonization patterns and strain relatedness, and the association between maternal and infant colonization in infancy. A birth cohort study was conducted from January 2012 to November 2014. Nasopharyngeal swabs for S. aureus detection were collected from infants at the age of 1, 2, 4, 6 and 12 months and from mothers when their children were 1-month-old. In total, 254 samples were collected at each planned visit during the first 12-month study. The prevalence of S. aureus colonization decreased in the first year of life, ranging from 61.0% (155/254) at the age of 1 month to 12.2% (31/254) at 12 months. Persistent colonization, defined as a positive culture on four or five occasions, was detected in only 13.8% (35/254) of carriers. Most of the persistent carriers were colonized with methicillin-resistant S. aureus (MRSA) only, and among persistent MRSA carriers, 61.1% (11/18) had indistinguishable genotypes. Of the mothers with MRSA colonization, 77.1% (27/35) had infants who were concomitantly colonized at the age of 1 month; 70.4% (19/27) of the infant-mother paired isolates belonged to indistinguishable or related subtypes, which suggests that surrounding carriers, probably their mothers, may be the possible source for MRSA acquisition in early infancy. Staphylococcus aureus colonization including MRSA was commonly observed in our cohort. Strains of persistent MRSA among infant-mother pairs were usually of indistinguishable genotypes. Therefore, horizontal spread within households is possibly an important factor related to infant MRSA colonization. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Price, Matthew J; Murray, Sarah S; Angiolillo, Dominick J; Lillie, Elizabeth; Smith, Erin N; Tisch, Rebecca L; Schork, Nicholas J; Teirstein, Paul S; Topol, Eric J
2012-05-29
This study sought to evaluate the influence of single nucleotide polymorphisms (SNPs) on the pharmacodynamic effect of high- or standard-dose clopidogrel after percutaneous coronary intervention (PCI). There is a lack of prospective, multicenter data regarding the effect of different genetic variants on clopidogrel pharmacodynamics over time in patients undergoing PCI. The GRAVITAS (Gauging Responsiveness with A VerifyNow assay-Impact on Thrombosis And Safety) trial screened patients with platelet function testing after PCI and randomly assigned those with high on-treatment reactivity (OTR) to either high- or standard-dose clopidogrel; a cohort of patients without high OTR were also followed. DNA samples obtained from 1,028 patients were genotyped for 41 SNPs in 17 genes related to platelet reactivity. After adjusting for clinical characteristics, the associations between the SNPs and OTR using linear regression were evaluated. CYP2C19*2 was significantly associated with OTR at 12 to 24 h (R(2) = 0.07, p = 2.2 × 10(-15)), 30 days (R(2) = 0.10, p = 1.3 × 10(-7)), and 6 months after PCI (R(2) = 0.07, p = 1.9 × 10(-11)), whereas PON1, ABCB1 3435 C→T, and other candidate SNPs were not. Carriers of 1 and 2 reduced-function CYP2C19 alleles were significantly more likely to display persistently high OTR at 30 days and 6 months, irrespective of treatment assignment. The portion of the risk of persistently high OTR at 30 days attributable to reduced-function CYP2C19 allele carriage was 5.2% in the patients randomly assigned to high-dose clopidogrel. CYP2C19, but not PON1 or ABCB1, is a significant determinant of the pharmacodynamic effects of clopidogrel, both early and late after PCI. In patients with high OTR identified by platelet function testing, the CYP2C19 genotype provides limited incremental information regarding the risk of persistently high reactivity with clopidogrel 150-mg maintenance dosing. (Genotype Information and Functional Testing Study [GIFT]; NCT00992420). Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Frequency and genotype of human parvovirus B19 among Iranian patients infected with HIV.
Azadmanesh, Kayhan; Mohraz, Minoo; Kazemimanesh, Monireh; Aghakhani, Arezoo; Foroughi, Maryam; Banifazl, Mohammad; Eslamifar, Ali; Ramezani, Amitis
2015-07-01
The human parvovirus B19 (B19) usually causes a subclinical infection in immunocompetent individuals. Whereas immunocompromised individuals such as patients infected with HIV are at risk of persistent anemia due to B19 infection. Only few studies have been carried out on distribution and molecular epidemiology of B19 in Iran. We aimed to determine the frequency and genotype of B19 among Iranian patients infected with HIV. We conducted a survey on 99 HIV patients and 64 healthy controls. IgG and IgM antibodies against B19 were detected by ELISA and B19 DNA was assessed by nested PCR. PCR products were subjected to direct sequencing and classified after phylogenetic analysis. The prevalence of B19 immunoglobulin was 11.1% for IgG and 1% for IgM. B19 DNA was detected in 13.1% of cases. The prevalence of B19 IgG, IgM, and DNA in control group was 25%, 1.6%, and 9.4%, respectively. B19 IgG was significantly lower in HIV group than in normal controls. There was no significant difference regarding anemia between cases and controls. All sequenced B19 isolates belonged to genotype 1A with low genetic diversity. Our findings indicated that in the HAART era, the importance of B19 infections in HIV patients may be limited whereas persistent B19 viremia in the circulation of healthy controls raises a potential concern in blood donations. © 2015 Wiley Periodicals, Inc.
Rosenberg, Gillian K; Lattimore, Sam; Brailsford, Susan R; Hewitt, Patricia E; Tettmar, Kate I; Kitchen, Alan D; Ijaz, Samreen; Tedder, Richard S
2014-06-01
Hepatitis B virus (HBV) remains the infection most frequently recognized by donation testing in blood donors. It is usually a persistent infection and mostly reflects the country of origin of the donor or the donor's family. There are, however, a minority of acute infections and this study undertook their phylogenetic analysis to determine the likely source of infection. Plasma samples from 11 donors donating between July 2005 and June 2010, whose test results revealed recent infection with hepatitis B, were available for further analysis. Plasma DNA was extracted, amplified, sequenced, and analyzed phylogenetically. Donor and virus characteristics were compared with the overall demography of all hepatitis B-infected donors attending over the same period. Three of the 11 individuals were first-time donors. Nine were male, of whom eight were white British. All had serum markers of very recent infection. Only two indicated known HBV exclusion risk factors at postdonation discussion not declared previously. Genotype A was present in seven, Genotype B in two, and Genotype C in two, contrasting with the pattern in persistently infected persons in the United Kingdom. A single A2 strain was identified in six of the white British male donors, suggesting epidemiologic linkage. Phylogenetic analysis of HBV-infected donors performed in real time can potentially lead to identification of undeclared risk factors that donor health questionnaires may fail to identify. © 2013 AABB.
Ghosh, Anirban; Baltekin, Özden; Wäneskog, Marcus; Elkhalifa, Dina; Hammarlöf, Disa L; Elf, Johan; Koskiniemi, Sanna
2018-05-02
Bacterial populations can use bet-hedging strategies to cope with rapidly changing environments. One example is non-growing cells in clonal bacterial populations that are able to persist antibiotic treatment. Previous studies suggest that persisters arise in bacterial populations either stochastically through variation in levels of global signalling molecules between individual cells, or in response to various stresses. Here, we show that toxins used in contact-dependent growth inhibition (CDI) create persisters upon direct contact with cells lacking sufficient levels of CdiI immunity protein, which would otherwise bind to and neutralize toxin activity. CDI-mediated persisters form through a feedforward cycle where the toxic activity of the CdiA toxin increases cellular (p)ppGpp levels, which results in Lon-mediated degradation of the immunity protein and more free toxin. Thus, CDI systems mediate a population density-dependent bet-hedging strategy, where the fraction of non-growing cells is increased only when there are many cells of the same genotype. This may be one of the mechanisms of how CDI systems increase the fitness of their hosts. © 2018 The Authors.
ERIC Educational Resources Information Center
Stevens, Hanna E.; Leckman, James F.; Coplan, Jeremy D.; Suomi, Stephen J.
2009-01-01
A literature review on macaque monkeys finds that peer rearing of young macaques and rearing of young macaques by mothers that are undergoing variable foraging conditions result in emotional and neurophysiological disturbance. Certain genotypes contribute to resilience to this disturbance. The findings have implications to child mental health and…
Ho, Gloria Y F; Einstein, Mark H; Romney, Seymour L; Kadish, Anna S; Abadi, Maria; Mikhail, Magdy; Basu, Jayasri; Thysen, Benjamin; Reimers, Laura; Palan, Prabhudas R; Trim, Shelly; Soroudi, Nafisseh; Burk, Robert D
2011-10-01
: This study examines risk factors for persistent cervical intraepithelial neoplasia (CIN) and examines whether human papillomavirus (HPV) testing predicts persistent lesions. : Women with histologically diagnosed CIN 1 or CIN 2 (n = 206) were followed up every 3 months without treatment. Human papillomavirus genotyping, plasma levels of ascorbic acid, and red blood cell folate levels were obtained. Cervical biopsy at 12 months determined the presence of CIN. Relative risk (RR) was estimated by log-linked binomial regression models. : At 12 months, 70% of CIN 1 versus 54% of CIN 2 lesions spontaneously regressed (p < .001). Levels of folate or ascorbic acid were not associated with persistent CIN at 12 months. Compared with HPV-negative women, those with multiple HPV types (RRs ranged from 1.68 to 2.17 at each follow-up visit) or high-risk types (RRs range = 1.74-2.09) were at increased risk for persistent CIN; women with HPV-16/18 had the highest risk (RRs range = 1.91-2.21). Persistent infection with a high-risk type was also associated with persistent CIN (RRs range = 1.50-2.35). Typing for high-risk HPVs at 6 months only had a sensitivity of 46% in predicting persistence of any lesions at 12 months. : Spontaneous regression of CIN 1 and 2 occurs frequently within 12 months. Human papillomavirus infection is the major risk factor for persistent CIN. However, HPV testing cannot reliably predict persistence of any lesion.
Otieno, James R.; Ngama, Mwanajuma; Mwihuri, Alexander G.; Medley, Graham F.; Cane, Patricia A.; Nokes, D. James
2015-01-01
ABSTRACT Respiratory syncytial virus (RSV) is a global respiratory pathogen of humans, with infection occurring characteristically as recurrent seasonal epidemics. Unlike influenza viruses, little attention has been paid to the mechanism underlying worldwide spread and persistence of RSV and how this may be discerned through an improved understanding of the introduction and persistence of RSV in local communities. We analyzed 651 attachment (G) glycoprotein nucleotide sequences of RSV B collected over 11 epidemics (2002 to 2012) in Kilifi, Kenya, and contemporaneous data collected elsewhere in Kenya and 18 other countries worldwide (2002 to 2012). Based on phylogeny, genetic distance and clustering patterns, we set out pragmatic criteria to classify local viruses into distinct genotypes and variants, identifying those newly introduced and those locally persisting. Three genotypes were identified in the Kilifi data set: BA (n = 500), SAB1 (n = 148), and SAB4 (n = 3). Recurrent RSV epidemics in the local population were composed of numerous genetic variants, most of which have been newly introduced rather than persisting in the location from season to season. Global comparison revealed that (i) most Kilifi variants do not cluster closely with strains from outside Kenya, (ii) some Kilifi variants were closely related to those observed outside Kenya (mostly Western Europe), and (iii) many variants were circulating elsewhere but were never detected in Kilifi. These results are consistent with the hypothesis that year-to-year presence of RSV at the local level (i.e., Kilifi) is achieved primarily, but not exclusively, through introductions from a pool of variants that are geographically restricted (i.e., to Kenya or to the region) rather than global. IMPORTANCE The mechanism by which RSV persists and reinvades local populations is poorly understood. We investigated this by studying the temporal patterns of RSV variants in a rural setting in tropical Africa and comparing these variants with contemporaneous variants circulating in other countries. We found that periodic seasonal RSV transmission at the local level appears to require regular new introductions of variants. However, importantly, the evidence suggests that the source of new variants is mostly geographically restricted, and we hypothesize that year-to-year RSV persistence is at the country level rather than the global level. This has implications for control. PMID:26355091
Price, Aryn A; Tedesco, Dana; Prasad, Mona R; Workowski, Kimberly A; Walker, Christopher M; Suthar, Mehul S; Honegger, Jonathan R; Grakoui, Arash
2016-09-20
Maternal innate and adaptive immune responses are modulated during pregnancy to concurrently defend against infection and tolerate the semiallogeneic fetus. The restoration of these systems after childbirth is poorly understood. We reasoned that enhanced innate immune activation may extend beyond gestation while adaptive immunity recovers. To test this hypothesis, the transcriptional profiles of total peripheral blood mononuclear cells following delivery in healthy women were compared with those of nonpregnant control subjects. Interestingly, interferon-stimulated genes (ISGs) encoding proteins such as IFIT1, IFIT2, and IFIT3, as well as signaling proteins such as STAT1, STAT2, and MAVS, were enriched postpartum. Antiviral genes were primarily expressed in CD14(+) cells and could be stratified according to genetic variation at the interferon-λ3 gene (IFNL3, also named IL28B) SNP rs12979860. Antiviral gene expression was sustained beyond 6 mo following delivery in mothers with a CT or TT genotype, but resembled baseline nonpregnant control levels following delivery in mothers with a CC genotype. CT and TT IFNL3 genotypes have been associated with persistent elevated ISG expression in individuals chronically infected with hepatitis C virus. Together, these data suggest that postpartum, the normalization of the physiological rheostat controlling IFN signaling depends on IFNL3 genotype.
Homayun, Bahman; Sun, Chengmeng; Kumar, Ankit; Montemagno, Carlo; Choi, Hyo-Jick
2018-05-10
Oral drugs present the most convenient, economical, and painless route for self-administration. Despite commercialization of multiple technologies relying on micro- and nanocrystalline drugs, research on microparticles (MPs) based oral biopharmaceuticals delivery systems has still not culminated well enough in commercial products. This is largely due to the drugs being exposed to the destabilizing environment during MP synthesis process, and partly because of complicated process conditions. Hence, we developed a solvent swelling-evaporation method of producing pH-responsive MPs with micron-sized macropores using poly(methacrylic acid-co-ethyl acrylate) in 1:1 ratio (commercial name: Eudragit ® L100-55 polymer). We investigated the effects of temperature and evaporation time on pore formation, freeze-drying induced pore closure, and the release profile of model drugs (fluorescent beads, lactase, and pravastatin sodium) encapsulated MPs in simulated gastrointestinal tract conditions. Encapsulated lactase/pravastatin maintained > 60% of their activity due to the preservation of pore closure, which proved the potential of this proof-of-concept microencapsulation system. Importantly, the presence of macropores on MPs can be beneficial for easy drug loading, and solve the problem of bioactivity loss during the conventional MP fabrication-drug encapsulation steps. Therefore, pH-sensing MPs with macropores can contribute to the development of oral drug formulations for a wide variety of drugs and bio-macromolecules, having a various size ranging from genes to micron-sized ingredients with high therapeutic efficacy. Copyright © 2018. Published by Elsevier B.V.
Tagliati, Sylvie; Saccomandi, Daniela; Brusaferro, Andrea; Busoli, Laura; Scala, Andrea; Malaventura, Cristina; Borgna-Pignatti, Caterina
2018-01-01
Adult-type hypolactasia (ATH) is a clinical syndrome of primary lactase deficiency. A lactose-free diet is advisable to avoid the symptoms linked to the condition, but this potentially creates problems for optimal bone mineralization due to reduced calcium intake. To evaluate the effect of the lactose-free diet on the bone mineral status (BMS), we compared the phalangeal BMS of adolescents with ATH to that of peers on a normal diet. Also, we analyzed the correlations between BMS and dietary behavior, physical exercise, and calcium and vitamin D intake. A total of 102 cases and 102 healthy controls filled out a diet record and underwent phalangeal Quantitative Ultrasound (QUS). No difference in BMS was observed. The time spent on lactose-free diet (4.8 ± 3.1 years) was inversely correlated to the BMS. More than 98% of cases consumed lactose-free milk, but calcium and vitamin D intake were significantly lower. Calcium intake was correlated to physical exercise but not to BMS. Our results suggest that a lactose-free diet does not affect the phalangeal BMS of adolescents with primary lactase deficiency when their diet includes lactose-free cow’s milk. However, there is still a significantly lower calcium intake than in the population reference. The inverse correlation observed between the BMS and the time spent on a lactose-free diet suggests that a long-term follow-up is advisable. PMID:29723971
In-host microevolution of Aspergillus fumigatus: A phenotypic and genotypic analysis.
Ballard, Eloise; Melchers, Willem J G; Zoll, Jan; Brown, Alistair J P; Verweij, Paul E; Warris, Adilia
2018-04-01
In order to survive, Aspergillus fumigatus must adapt to specific niche environments. Adaptation to the human host includes modifications facilitating persistent colonisation and the development of azole resistance. The aim of this study is to advance understanding of the genetic and physiological adaptation of A. fumigatus in patients during infection and treatment. Thirteen A. fumigatus strains were isolated from a single chronic granulomatous disease patient suffering from persistent and recurrent invasive aspergillosis over a period of 2 years. All strains had identical microsatellite genotypes and were considered isogenic. Whole genome comparisons identified 248 non-synonymous single nucleotide polymorphisms. These non-synonymous mutations have potential to play a role in in-host adaptation. The first 2 strains isolated were azole susceptible, whereas later isolates were itraconazole, voriconazole and/or posaconazole resistant. Growth assays in the presence and absence of various antifungal stressors highlighted minor changes in growth rate and stress resistance, with exception of one isolate showing a significant growth defect. Poor conidiation was observed in later isolates. In certain drug resistant isolates conidiation was restored in the presence of itraconazole. Differences in virulence were observed as demonstrated in a Galleria mellonella infection model. We conclude that the microevolution of A. fumigatus in this patient has driven the emergence of both Cyp51A-independent and Cyp51A-dependent, azole resistance mechanisms, and additional phenotypes that are likely to have promoted fungal persistence. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.
An American termite in Paris: temporal colony dynamics.
Baudouin, Guillaume; Dedeine, Franck; Bech, Nicolas; Bankhead-Dronnet, Stéphanie; Dupont, Simon; Bagnères, Anne-Geneviève
2017-12-01
Termites of the genus Reticulitermes are widespread invaders, particularly in urban habitats. Their cryptic and subterranean lifestyle makes them difficult to detect, and we know little about their colony dynamics over time. In this study we examined the persistence of Reticulitermes flavipes (Kollar) colonies in the city of Paris over a period of 15 years. The aim was (1) to define the boundaries of colonies sampled within the same four areas over two sampling periods, (2) to determine whether the colonies identified during the first sampling period persisted to the second sampling period, and (3) to compare the results obtained when colonies were delineated using a standard population genetic approach versus a Bayesian clustering method that combined both spatial and genetic information. Herein, colony delineations were inferred from genetic differences at nine microsatellite loci and one mitochondrial locus. Four of the 18 identified colonies did not show significant differences in their genotype distributions between the two sampling periods. While allelic richness was low, making it hard to reliably distinguish colony family type, most colonies appeared to retain the same breeding structure over time. These large and expansive colonies showed an important ability to fuse (39% were mixed-family colonies), contained hundreds of reproductives and displayed evidence of isolation-by-distance, suggesting budding dispersal. These traits, which favor colony persistence over time, present a challenge for pest control efforts, which apply treatment locally. The other colonies showed significant differences, but we cannot exclude the possibility that their genotype distributions simply changed over time.
Rotavirus Strain Trends During the Postlicensure Vaccine Era: United States, 2008-2013.
Bowen, Michael D; Mijatovic-Rustempasic, Slavica; Esona, Mathew D; Teel, Elizabeth N; Gautam, Rashi; Sturgeon, Michele; Azimi, Parvin H; Baker, Carol J; Bernstein, David I; Boom, Julie A; Chappell, James; Donauer, Stephanie; Edwards, Kathryn M; Englund, Janet A; Halasa, Natasha B; Harrison, Christopher J; Johnston, Samantha H; Klein, Eileen J; McNeal, Monica M; Moffatt, Mary E; Rench, Marcia A; Sahni, Leila C; Selvarangan, Rangaraj; Staat, Mary A; Szilagyi, Peter G; Weinberg, Geoffrey A; Wikswo, Mary E; Parashar, Umesh D; Payne, Daniel C
2016-09-01
Group A rotaviruses (RVA) are a significant cause of pediatric gastroenteritis worldwide. The New Vaccine Surveillance Network (NVSN) has conducted active surveillance for RVA at pediatric hospitals and emergency departments at 3-7 geographically diverse sites in the United States since 2006. Over 6 consecutive years, from 2008 to 2013, 1523 samples from NVSN sites that were tested positive by a Rotaclone enzyme immunoassay were submitted to the Centers for Disease Control and Prevention for genotyping. In the 2009, 2010, and 2011 seasons, genotype G3P[8] was the predominant genotype throughout the network, with a 46%-84% prevalence. In the 2012 season, G12P[8] replaced G3P[8] as the most common genotype, with a 70% prevalence, and this trend persisted in 2013 (68.0% prevalence). Vaccine (RotaTeq; Rotarix) strains were detected in 0.6%-3.4% of genotyped samples each season. Uncommon and unusual strains (eg, G8P[4], G3P[24], G2P[8], G3P[4], G3P[6], G24P[14], G4P[6], and G9P[4]) were detected sporadically over the study period. Year, study site, and race were found to be significant predictors of genotype. Continued active surveillance is needed to monitor RVA genotypes in the United States and to detect potential changes since vaccine licensure. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Multiple norovirus infections in a birth cohort in a Peruvian Periurban community.
Saito, Mayuko; Goel-Apaza, Sonia; Espetia, Susan; Velasquez, Daniel; Cabrera, Lilia; Loli, Sebastian; Crabtree, Jean E; Black, Robert E; Kosek, Margaret; Checkley, William; Zimic, Mirko; Bern, Caryn; Cama, Vitaliano; Gilman, Robert H
2014-02-01
Human noroviruses are among the most common enteropathogens globally, and are a leading cause of infant diarrhea in developing countries. However, data measuring the impact of norovirus at the community level are sparse. We followed a birth cohort of children to estimate norovirus infection and diarrhea incidence in a Peruvian community. Stool samples from diarrheal episodes and randomly selected nondiarrheal samples were tested by polymerase chain reaction for norovirus genogroup and genotype. Excretion duration and rotavirus coinfection were evaluated in a subset of episodes. Two hundred twenty and 189 children were followed to 1 and 2 years of age, respectively. By 1 year, 80% (95% confidence interval [CI], 75%-85%) experienced at least 1 norovirus infection and by 2 years, 71% (95% CI, 65%-77%) had at least 1 episode of norovirus-associated diarrhea. Genogroup II (GII) infections were 3 times more frequent than genogroup 1 (GI) infections. Eighteen genotypes were found; GII genotype 4 accounted for 41%. Median excretion duration was 34.5 days for GII vs 8.5 days for GI infection (P = .0006). Repeat infections by the same genogroup were common, but repeat infections by the same genotype were rare. Mean length-for-age z score at 12 months was lower among children with prior norovirus infection compared to uninfected children (coefficient: -0.33 [95% CI, -.65 to -.01]; P = .04); the effect persisted at 24 months. Norovirus infection occurs early in life and children experience serial infections with multiple genotypes, suggesting genotype-specific immunity. An effective vaccine would have a substantial impact on morbidity, but may need to target multiple genotypes.
The elephants of Gash-Barka, Eritrea: nuclear and mitochondrial genetic patterns.
Brandt, Adam L; Hagos, Yohannes; Yacob, Yohannes; David, Victor A; Georgiadis, Nicholas J; Shoshani, Jeheskel; Roca, Alfred L
2014-01-01
Eritrea has one of the northernmost populations of African elephants. Only about 100 elephants persist in the Gash-Barka administrative zone. Elephants in Eritrea have become completely isolated, with no gene flow from other elephant populations. The conservation of Eritrean elephants would benefit from an understanding of their genetic affinities to elephants elsewhere on the continent and the degree to which genetic variation persists in the population. Using dung samples from Eritrean elephants, we examined 18 species-diagnostic single nucleotide polymorphisms in 3 nuclear genes, sequences of mitochondrial HVR1 and ND5, and genotyped 11 microsatellite loci. The sampled Eritrean elephants carried nuclear and mitochondrial DNA markers establishing them as savanna elephants, with closer genetic affinity to Eastern than to North Central savanna elephant populations, and contrary to speculation by some scholars that forest elephants were found in Eritrea. Mitochondrial DNA diversity was relatively low, with 2 haplotypes unique to Eritrea predominating. Microsatellite genotypes could only be determined for a small number of elephants but suggested that the population suffers from low genetic diversity. Conservation efforts should aim to protect Eritrean elephants and their habitat in the short run, with restoration of habitat connectivity and genetic diversity as long-term goals.
Massive dispersal of Coxiella burnetii among cattle across the United States
Olivas, Sonora; Hornstra, Heidie; Priestley, Rachael A.; Kaufman, Emily; Hepp, Crystal; Sonderegger, Derek L.; Handady, Karthik; Massung, Robert F.; Keim, Paul; Kersh, Gilbert J.
2016-01-01
Q-fever is an underreported disease caused by the bacterium Coxiella burnetii, which is highly infectious and has the ability to disperse great distances. It is a completely clonal pathogen with low genetic diversity and requires whole-genome analysis to identify discriminating features among closely related isolates. C. burnetii, and in particular one genotype (ST20), is commonly found in cow’s milk across the entire dairy industry of the USA. This single genotype dominance is suggestive of host-specific adaptation, rapid dispersal and persistence within cattle. We used a comparative genomic approach to identify SNPs for high-resolution and high-throughput genotyping assays to better describe the dispersal of ST20 across the USA. We genotyped 507 ST20 cow milk samples and discovered three subgenotypes, all of which were present across the entire country and over the complete time period studied. Only one of these sub-genotypes was observed in a single dairy herd. The temporal and geographic distribution of these sub-genotypes is consistent with a model of large-scale, rapid, frequent and continuous dissemination on a continental scale. The distribution of subgenotypes is not consistent with wind-based dispersal alone, and it is likely that animal husbandry and transportation practices, including pooling of milk from multiple herds, have also shaped the patterns. On the scale of an entire country, there appear to be few barriers to rapid, frequent and large-scale dissemination of the ST20 subgenotypes. PMID:28348863
Shiramizu, Bruce; Liang, Chin-Yuan; Agsalda-Garcia, Melissa; Nagata, Ian; Milne, Cris; Zhu, Xuemei; Killeen, Jeffrey; Berry, J Michael; Goodman, Marc T
2013-01-01
Human immunodeficiency virus type 1 (HIV)-infected individuals are at risk for anal cancer, which is caused by human papillomavirus (HPV). The relationship between HIV and HPV that leads to anal cancer remains unclear. Recent data, however, suggest that the continued persistence of HIV DNA in patients treated with combined antiretroviral therapy leads to progression of HIV disease and other HIV-associated complications. Therefore, we investigated the relationship among anal low- and high-grade squamous intraepithelial lesions (LGSIL/HGSIL), high-risk HPV genotypes, and high HIV DNA copy numbers. Anal cytology specimens were assayed for HPV genotype and HIV DNA copy number. High-risk HPV genotypes (odds ratio OR: 3.73; 95% confidence interval CI: 1.08-12.91; p=0.04) and high HIV DNA copy numbers (OR(per 100 HIV DNA copies): 1.13; 95% CI: 1.01-1.27, p=0.04) were both associated with LGSIL/HGSIL. When considering both high-risk HPV genotypes and HIV DNA copy numbers in predicting LGSIL/HGSIL, HIV DNA copy number was significant (OR(per 100 HIV DNA copies): 1.09; 95% CI: 0.96-1.23, p=0.04) but not high-risk HPV genotypes (OR: 2.30, p=0.28), which did not change when adjusted for nadir CD4 cell count and HIV RNA levels. The findings warrant further investigation of HIV DNA and its relationship with HPV in LGSIL/HGSIL pathogenesis.
Human Papilloma Virus Genotype Distribution in Cervical lesions in Zanjan, Iran
Ahmadi, Shahrzad; Goudarzi, Hossein; Jalilvand, Ahmad; Esmaeilzadeh, Abdolreza
2017-12-29
Objective: Cervical cancer is one of the most common cancers among women all over the world, and main cause is persistent infection with high risk human papillomavirus (HPV) strains. It has been reported that the distribution and prevalence of HPV types varies by geographical region, so that this is important for prevention by type-specific vaccines. The aim of current study was to determine the genotype distribution of HPV using the INNO-LiPA genotyping assay in Zanjan province, North West Iran. Methods: A total of 112 formalin-fixed paraffin embedded (FFPE) tissue samples from cases of low-grade intraepithelial lesion (LSIL), high-grade intraepithelial lesion (HSIL) and squamous cell carcinoma (SCC) were collected. The polymerase chain reaction (PCR) was used to amplify DNA for genotyping. Results: Among the 112 samples from females (ranging from 20 to 69 years, mean age 43.8 ± 10.1) tested for HPV DNA, 50 samples were positive. Based on results of genotyping, most common HPV genotypes were HPV18 (48%) followed by HPV-6 (24%), HPV73 (16%), HPV-51(8%), HPV-31(8%), HPV-16 (8%), HPV-56 (4%), HPV-44 (4%). Conclusion: While HPV infection is the major etiological factor for cervical cancer, presence was relatively low in our survey. In the positive cases, however, HPV18 was the most common in line with many other populations. The fact that types vary among different populations must clearly be taken into account in design of vaccines for our country. Creative Commons Attribution License
Lucarelli, Marco; Bruno, Sabina Maria; Pierandrei, Silvia; Ferraguti, Giampiero; Stamato, Antonella; Narzi, Fabiana; Amato, Annalisa; Cimino, Giuseppe; Bertasi, Serenella; Quattrucci, Serena; Strom, Roberto
2015-01-01
Cystic fibrosis (CF) is a monogenic disease caused by mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The genotype–phenotype relationship in this disease is still unclear, and diagnostic, prognostic and therapeutic challenges persist. We enrolled 610 patients with different forms of CF and studied them from a clinical, biochemical, microbiological and genetic point of view. Overall, there were 125 different mutated alleles (11 with novel mutations and 10 with complex mutations) and 225 genotypes. A strong correlation between mutational patterns at the genotypic level and phenotypic macrocategories emerged. This specificity appears to largely depend on rare and individual mutations, as well as on the varying prevalence of common alleles in different clinical macrocategories. However, 19 genotypes appeared to underlie different clinical forms of the disease. The dissection of the pathway from the CFTR mutated genotype to the clinical phenotype allowed to identify at least two components of the variability usually found in the genotype–phenotype relationship. One component seems to depend on the genetic variation of CFTR, the other component on the cumulative effect of variations in other genes and cellular pathways independent from CFTR. The experimental dissection of the overall biological CFTR pathway appears to be a powerful approach for a better comprehension of the genotype–phenotype relationship. However, a change from an allele-oriented to a genotypic-oriented view of CFTR genetics is mandatory, as well as a better assessment of sources of variability within the CFTR pathway. PMID:25910067
Community-acquired methicillin-resistant Staphylococcus aureus can persist in the throat.
Hamdan-Partida, Aida; González-García, Samuel; de la Rosa García, Estela; Bustos-Martínez, Jaime
2018-06-01
Colonization by Staphylococcus aureus is an important factor in infections caused by this microorganism. Among the colonization niches of staphylococci are the nose, skin, intestinal tract, and, recently, the throat has been given relevance. Infections caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) can be fatal. Persistence of S. aureus is an important process in the pathogenesis of this microorganism and must be studied. The aim of this study was to determine the persistence of S. aureus in the throat, and characterized the strains. We studied the persistence of S. aureus for 6 years in the throat of apparently healthy people. The isolated strains from the persistent carriers were characterized through PFGE, spa-typing, SCCmec typing, resistance to methicillin, presence of virulence genes (adhesins and toxins), and the formation of biofilm. We found persistent and intermittent carriers of S. aureus in the throat, with methicillin-sensitive (MSSA), methicillin-resistant (MRSA) strains, and confirmed for the first time that CA-MRSA colonizes this niche. These strains can colonize persistently the throat for four years or more. Typification of strains through PFGE and spa-typing revealed that some carriers present the same strain, whereas others present different strains along the period of persistence. Almost all strains induced a strong biofilm formation. All strains presented adhesin and toxin genes, but no shared genotype was found. We conclude that S. aureus, including CA-MRSA strains, can remain persistently in the throat, finding a wide variability among the persistent strains. Copyright © 2018 Elsevier GmbH. All rights reserved.
Youn, Jin-Won; Hu, Yu-Wen; Tricoche, Nancy; Pfahler, Wolfram; Shata, Mohamed Tarek; Dreux, Marlene; Cosset, François-Loic; Folgori, Antonella; Lee, Dong-Hun; Brotman, Betsy; Prince, Alfred M.
2008-01-01
Given the failures of nonreplicating vaccines against chronic hepatitis C virus (HCV) infection, we hypothesized that a replicating viral vector may provide protective immunity. Four chimpanzees were immunized transdermally twice with recombinant vaccinia viruses (rVV) expressing HCV genes. After challenge with 24 50% chimpanzee infective doses of homologous HCV, the two control animals that had received only the parental VV developed chronic HCV infection. All four immunized animals resolved HCV infection. The difference in the rate of chronicity between the immunized and the control animals was close to statistical significance (P = 0.067). Immunized animals developed vigorous gamma interferon enzyme-linked immunospot responses and moderate proliferative responses. To investigate cross-genotype protection, the immunized recovered chimpanzees were challenged with a pool of six major HCV genotypes. During the acute phase after the multigenotype challenge, all animals had high-titer viremia in which genotype 4 dominated (87%), followed by genotype 5 (13%). However, after fluctuating low-level viremia, the viremia finally turned negative or persisted at very low levels. This study suggests the potential efficacy of replicating recombinant vaccinia virus-based immunization against chronic HCV infection. PMID:18753204
Marchal, Marie; Goldschmidt, Felix; Derksen-Müller, Selina N; Panke, Sven; Ackermann, Martin; Johnson, David R
2017-04-24
While mutualistic interactions between different genotypes are pervasive in nature, their evolutionary origin is not clear. The dilemma is that, for mutualistic interactions to emerge and persist, an investment into the partner genotype must pay off: individuals of a first genotype that invest resources to promote the growth of a second genotype must receive a benefit that is not equally accessible to individuals that do not invest. One way for exclusive benefits to emerge is through spatial structure (i.e., physical barriers to the movement of individuals and resources). Here we propose that organisms can evolve their own spatial structure based on physical attachment between individuals, and we hypothesize that attachment evolves when spatial proximity to members of another species is advantageous. We tested this hypothesis using experimental evolution with combinations of E. coli strains that depend on each other to grow. We found that attachment between cells repeatedly evolved within 8 weeks of evolution and observed that many different types of mutations potentially contributed to increased attachment. We postulate a general principle by which passive beneficial interactions between organisms select for attachment, and attachment then provides spatial structure that could be conducive for the evolution of active mutualistic interactions.
Detection and identification of Chlamydophila psittaci in asymptomatic parrots in Poland
2012-01-01
Background Psittacosis, an avian disease caused by Chlamydophila psittaci, can manifest as an acute, protracted, or chronic illness, but can also be asymptomatic. C. psittaci can persist in the host for months to years, often without causing obvious illness, and therefore poses a threat for zoonotic outbreak. We investigated the prevalence of C. psittaci from 156 tracheal swab samples from 34 different species of parrots in Poland, and determined the genotype of strains from the positive samples. Results An overall prevalence of 10.3% was observed using two different PCR assays, both providing similar results. Thirteen of the PCR-positive samples were genotype A, two were genotype B, and one could not be classified. Conclusions These results indicate widespread dissemination of C. psittaci in Polish psittacine populations, without any clinical signs of chlamydiosis, and hence could pose a zoonotic hazard. PCR screening provided a definitive diagnosis of psittacosis, and subsequent ompA gene analysis could be helpful for better understanding the epidemiology of the C. psittaci genotypes. To the best of our knowledge, this is the first report of the incidence of C. psittaci in parrots in Poland. PMID:23206592
Hayden, Eric J
2016-08-15
RNA molecules provide a realistic but tractable model of a genotype to phenotype relationship. This relationship has been extensively investigated computationally using secondary structure prediction algorithms. Enzymatic RNA molecules, or ribozymes, offer access to genotypic and phenotypic information in the laboratory. Advancements in high-throughput sequencing technologies have enabled the analysis of sequences in the lab that now rivals what can be accomplished computationally. This has motivated a resurgence of in vitro selection experiments and opened new doors for the analysis of the distribution of RNA functions in genotype space. A body of computational experiments has investigated the persistence of specific RNA structures despite changes in the primary sequence, and how this mutational robustness can promote adaptations. This article summarizes recent approaches that were designed to investigate the role of mutational robustness during the evolution of RNA molecules in the laboratory, and presents theoretical motivations, experimental methods and approaches to data analysis. Copyright © 2016 Elsevier Inc. All rights reserved.
Vanlandingham, Dana L.; McGee, Charles E.; Klingler, Kimberly A.; Galbraith, Sareen E.; Barrett, Alan D. T.; Higgs, Stephen
2009-01-01
Phylogenetic analysis of West Nile virus in North America has identified replacement of the originally introduced clade, Eastern United States (NY99), by the North American clade. In addition, the transient emergence of other clades and genetic variants has also been observed. In this study, we investigated the potential role of the mosquito in the selection of these clades and genetic variants. We determined the relative susceptibility of Culex quinquefasciatus to infection with isolates from the Eastern U.S. clade, the North American clade, and the Southeast coastal Texas clade. Although significant differences were observed in 50% oral infectious dose values between the Eastern U.S. and two attenuated North American genetic variants compared with the North American and Southeast coastal Texas clade viruses, these differences did not correlate with persistence of the genotype in nature. These results indicate that selection of these viral genotypes was independent of viral oral infectivity in the mosquito. PMID:19052310
Natural genetic variation in Arabidopsis thaliana defense metabolism genes modulates field fitness.
Kerwin, Rachel; Feusier, Julie; Corwin, Jason; Rubin, Matthew; Lin, Catherine; Muok, Alise; Larson, Brandon; Li, Baohua; Joseph, Bindu; Francisco, Marta; Copeland, Daniel; Weinig, Cynthia; Kliebenstein, Daniel J
2015-04-13
Natural populations persist in complex environments, where biotic stressors, such as pathogen and insect communities, fluctuate temporally and spatially. These shifting biotic pressures generate heterogeneous selective forces that can maintain standing natural variation within a species. To directly test if genes containing causal variation for the Arabidopsis thaliana defensive compounds, glucosinolates (GSL) control field fitness and are therefore subject to natural selection, we conducted a multi-year field trial using lines that vary in only specific causal genes. Interestingly, we found that variation in these naturally polymorphic GSL genes affected fitness in each of our environments but the pattern fluctuated such that highly fit genotypes in one trial displayed lower fitness in another and that no GSL genotype or genotypes consistently out-performed the others. This was true both across locations and within the same location across years. These results indicate that environmental heterogeneity may contribute to the maintenance of GSL variation observed within Arabidopsis thaliana.
Reconstructing genome evolution in historic samples of the Irish potato famine pathogen
Martin, Michael D.; Cappellini, Enrico; Samaniego, Jose A.; Zepeda, M. Lisandra; Campos, Paula F.; Seguin-Orlando, Andaine; Wales, Nathan; Orlando, Ludovic; Ho, Simon Y. W.; Dietrich, Fred S.; Mieczkowski, Piotr A.; Heitman, Joseph; Willerslev, Eske; Krogh, Anders; Ristaino, Jean B.; Gilbert, M. Thomas P.
2013-01-01
Responsible for the Irish potato famine of 1845–49, the oomycete pathogen Phytophthora infestans caused persistent, devastating outbreaks of potato late blight across Europe in the 19th century. Despite continued interest in the history and spread of the pathogen, the genome of the famine-era strain remains entirely unknown. Here we characterize temporal genomic changes in introduced P. infestans. We shotgun sequence five 19th-century European strains from archival herbarium samples—including the oldest known European specimen, collected in 1845 from the first reported source of introduction. We then compare their genomes to those of extant isolates. We report multiple distinct genotypes in historical Europe and a suite of infection-related genes different from modern strains. At virulence-related loci, several now-ubiquitous genotypes were absent from the historical gene pool. At least one of these genotypes encodes a virulent phenotype in modern strains, which helps explain the 20th century’s episodic replacements of European P. infestans lineages. PMID:23863894
Janssen, Paddy K C; Bakker, Steven C; Réthelyi, Janos; Zwinderman, Aeilko H; Touw, Daan J; Olivier, Berend; Waldinger, Marcel D
2009-01-01
Lifelong premature ejaculation (LPE) is characterized by persistent intravaginal ejaculation latency times (IELTs) of less than 1 minute, and has been postulated as a neurobiological dysfunction with genetic vulnerability for the short IELTs, related to disturbances of central serotonin (5-hydroxytryptamine [5-HT]) neurotransmission and 5-HT receptor functioning. To investigate the relationship between 5-HT transporter gene-linked polymorphism (5-HTTLPR) and short IELTs in men with lifelong PE. A prospective study was conducted in 89 Dutch Caucasian men with lifelong PE. IELT during coitus was assessed by stopwatch over a 1-month period. Controls consisted of 92 Dutch Caucasian men. All men with LPE were genotyped for a 5-HTT-promoter polymorphism. Allele frequencies and genotypes of short (S) and long (L) variants of 5-HTTLPR polymorphism were compared between patients and controls. Association between LL, SL, and SS genotypes, and the natural logarithm of the IELT in men with LPE was investigated. IELT measured by stopwatch, 5-HTTLPR polymorphism. In men with lifelong PE, the geometric mean, median, and natural mean IELTs were 21, 26, and 32 seconds, respectively. There were no significant differences in the 5-HTT polymorphism alleles and genotypes between 89 Dutch Caucasian men with LPE (S 47%, L 53%/LL 29%, SL 48%, SS 22%) and 92 Dutch Caucasian controls (S 48%, L 52%/LL 29%, SL 45%, SS 26%). In men with lifelong PE there was a statistically significant difference between LL, SL, and SS genotypes in their geometric mean IELT (P < or = 0.027); the LL genotypes had significantly shorter IELTs than the SS and SL genotypes. The 5-HTTLPR polymorphism is associated with significant effects on the latency to ejaculate in men with lifelong PE. Men with SS and SL genotypes have 100% and 90% longer ejaculation time, respectively than men with LL genotypes.
Evolutionary history and spatiotemporal dynamics of DENV-1 genotype V in the Americas.
de Bruycker-Nogueira, Fernanda; Mir, Daiana; Dos Santos, Flavia Barreto; Bello, Gonzalo
2016-11-01
The genotype V has been the most prevalent dengue virus type 1 (DENV-1) clade circulating in the Americas over the last 40years. In this study, we investigate the spatiotemporal pattern of emergence and dissemination of DENV-1 lineages in the continent. We applied phylogenetic and phylogeographic approaches to a comprehensive data set of 836 DENV-1 E gene sequences of the genotype V isolated from 46 different countries around the world over a period of 50years (1962 to 2014). Our study reveals that genetic diversity of DENV-1 genotype V in the Americas resulted from two independent introductions of this genotype from India. The first genotype V strain was most probably introduced into the Lesser Antilles at around the early 1970s and this Caribbean region becomes the source population of several DENV-1 lineages that spread in the Americas during the 1970s and 1980s. Most of those lineages appear to become extinct during the 1990s, except one that persisted in Venezuela and later spread to other American countries, dominating the DENV-1 epidemics in the region from the early 2000s onwards. The second genotype V strain of Indian origin was also most probably introduced into the Lesser Antilles at around the early 1980s. This lineage remained almost undetected for nearly 15years, until it was introduced in Northern Brazil around the middle 1990s and later spread to other country regions. These results demonstrate that different geographic regions have played a role in maintaining and spreading the DENV-1 genotype V in the Americas over time. DENV-1 genotype V lineages have originated, spread and died out in the Americas with very different dynamics and the phenomenon of lineage replacement across successive DENV-1 epidemic outbreaks was a common characteristic in most American countries. Copyright © 2016 Elsevier B.V. All rights reserved.
Heritability of Respiratory Infection with Pseudomonas aeruginosa in Cystic Fibrosis
Green, Deanna M.; Collaco, J. Michael; McDougal, Kathryn E.; Naughton, Kathleen M.; Blackman, Scott M.; Cutting, Garry R.
2013-01-01
Objective To quantify the relative contribution of factors other than cystic fibrosis transmembrane conductance regulator genotype and environment on the acquisition of Pseudomonas aeruginosa (Pa) by patients with cystic fibrosis. Study design Lung infection with Pa and mucoid Pa was assessed using a co-twin study design of 44 monozygous (MZ) and 17 dizygous (DZ) twin pairs. Two definitions were used to establish infection: first positive culture and persistent positive culture. Genetic contribution to infection (ie, heritability) was estimated based on concordance analysis, logistic regression, and age at onset of infection through comparison of intraclass correlation coefficients. Results Concordance for persistent Pa infection was higher in MZ (0.83; 25 of 30 pairs) than DZ twins (0.45; 5 of 11 pairs), generating a heritability of 0.76. Logistic regression adjusted for age corroborated genetic control of persistent Pa infection. The correlation for age at persistent Pa infection was higher in MZ twins (0.589; 95% CI, 0.222-0.704) than in DZ twins (0.162; 95% CI, −0.352 to 0.607), generating a heritability of 0.85. Conclusion Genetic modifiers play a significant role in the establishment and timing of persistent Pa infection in individuals with cystic fibrosis. PMID:22364820
2011-01-01
Background Natural Killer (NK) cells are the most abundant lymphocytes in the decidua during early gestation. The interactions of NK cells with the extravillous cytotrophoblast have been associated with a normal spiral artery remodeling process, an essential event for a successful pregnancy. Recent data indicate that alterations in the amount of decidual NK (dNK) cells contribute to the development of preeclampsia (PE). Moreover, genetic studies suggest that Killer Immunoglobulin-like Receptors (KIR) expressed in dNK cells influence the susceptibility to PE. Although dNK cells have been well characterized during early pregnancy, they have been scarcely studied in the third trimester of gestation. The aim of this work was to characterize dNK cells at the last trimester of gestation and to analyze the KIR genotype of healthy and PE women. Methods Decidual samples were obtained during Caesarean section from control (n = 10) and PE (n = 9) women. Flow cytometric analysis of CD3, CD56, CD16 and CD9 was used to characterize and quantify dNK cells in both groups. Cell surface markers from decidual leukocytes were compared with PBMC from healthy donors. KIR genotyping was performed in genomic DNA (control, n = 86; PE, n = 90) using PCR-SSP. Results The results indicate that dNK cells persist throughout pregnancy. They represented 20% of total leukocytes in control and PE groups, and they expressed the same cell surface markers (CD3-, CD56+, CD16- and CD9+) as dNK in the first trimester of gestation. There were no significant differences in the percentage of dNK cells between control and PE groups. The analysis of KIR gene frequencies and genotypes was not statistically different between control and PE groups. The ratio of activating to inhibitory genes indicated that the overall inhibitory balance (0.2-0.5) was more frequent in the PE group (control, 31.3% vs PE, 45.5%), and the activating balance (0.6-1.1) was more frequent in the control group (control, 68.6% vs PE, 54.4%). However this difference was not significant. Conclusion We demonstrated the persistence of dNK cells in PE and control women at the third trimester of pregnancy; these dNK cells had a similar phenotype to those found during early pregnancy. The predominance of a KIR inhibitory balance in the PE group could be associated to the physiopathology of PE. PMID:21247496
Multiple Norovirus Infections in a Birth Cohort in a Peruvian Periurban Community
Saito, Mayuko; Goel-Apaza, Sonia; Espetia, Susan; Velasquez, Daniel; Cabrera, Lilia; Loli, Sebastian; Crabtree, Jean E.; Black, Robert E.; Kosek, Margaret; Checkley, William; Zimic, Mirko; Bern, Caryn; Cama, Vitaliano; Gilman, Robert H.; Xiao, L.; Kelleher, D.; Windle, H. J.; van Doorn, L. J.; Varela, M.; Verastegui, M.; Calderon, M.; Alva, A.; Roman, K.
2014-01-01
Background. Human noroviruses are among the most common enteropathogens globally, and are a leading cause of infant diarrhea in developing countries. However, data measuring the impact of norovirus at the community level are sparse. Methods. We followed a birth cohort of children to estimate norovirus infection and diarrhea incidence in a Peruvian community. Stool samples from diarrheal episodes and randomly selected nondiarrheal samples were tested by polymerase chain reaction for norovirus genogroup and genotype. Excretion duration and rotavirus coinfection were evaluated in a subset of episodes. Results. Two hundred twenty and 189 children were followed to 1 and 2 years of age, respectively. By 1 year, 80% (95% confidence interval [CI], 75%–85%) experienced at least 1 norovirus infection and by 2 years, 71% (95% CI, 65%–77%) had at least 1 episode of norovirus-associated diarrhea. Genogroup II (GII) infections were 3 times more frequent than genogroup 1 (GI) infections. Eighteen genotypes were found; GII genotype 4 accounted for 41%. Median excretion duration was 34.5 days for GII vs 8.5 days for GI infection (P = .0006). Repeat infections by the same genogroup were common, but repeat infections by the same genotype were rare. Mean length-for-age z score at 12 months was lower among children with prior norovirus infection compared to uninfected children (coefficient: −0.33 [95% CI, −.65 to −.01]; P = .04); the effect persisted at 24 months. Conclusions. Norovirus infection occurs early in life and children experience serial infections with multiple genotypes, suggesting genotype-specific immunity. An effective vaccine would have a substantial impact on morbidity, but may need to target multiple genotypes. PMID:24300042
Ives, A-K; Antaki, E; Stewart, K; Francis, S; Jay-Russell, M T; Sithole, F; Kearney, M T; Griffin, M J; Soto, E
2017-09-01
Salmonellae are Gram-negative zoonotic bacteria that are frequently part of the normal reptilian gastrointestinal flora. The main objective of this project was to estimate the prevalence of non-typhoidal Salmonella enterica in the nesting and foraging populations of sea turtles on St. Kitts and in sand from known nesting beaches. Results suggest a higher prevalence of Salmonella in nesting leatherback sea turtles compared with foraging green and hawksbill sea turtles. Salmonella was cultured from 2/9 and identified by molecular diagnostic methods in 3/9 leatherback sea turtle samples. Salmonella DNA was detected in one hawksbill turtle, but viable isolates were not recovered from any hawksbill sea turtles. No Salmonella was detected in green sea turtles. In samples collected from nesting beaches, Salmonella was only recovered from a single dry sand sample. All recovered isolates were positive for the wzx gene, consistent with the O:7 serogroup. Further serotyping characterized serovars Montevideo and Newport present in cloacal and sand samples. Repetitive-element palindromic PCR (rep-PCR) fingerprint analysis and pulsed-field gel electrophoresis of the 2014 isolates from turtles and sand as well as archived Salmonella isolates recovered from leatherback sea turtles in 2012 and 2013, identified two distinct genotypes and four different pulsotypes, respectively. The genotyping and serotyping were directly correlated. To determine the persistence of representative strains of each serotype/genotype in these environments, laboratory-controlled microcosm studies were performed in water and sand (dry and wet) incubated at 25 or 35°C. Isolates persisted for at least 32 days in most microcosms, although there were significant decreases in culturable bacteria in several microcosms, with the greatest reduction in dry sand incubated at 35°C. This information provides a better understanding of the epizootiology of Salmonella in free-ranging marine reptiles and the potential public health risks associated with human interactions with these animals in the Caribbean. © 2016 Blackwell Verlag GmbH.
Byappanahalli, M.N.; Whitman, R.L.; Shively, D.A.; Ting, W.T.E.; Tseng, C.C.; Nevers, M.B.
2006-01-01
We studied the shoreward and seasonal distribution of E. coli and enterococci in sand (at the water table) at two southern Lake Michigan beaches - Dunbar and West Beach (in Indiana). Deep, backshore sand (??? 20 m inland) was regularly sampled for 15 months during 2002-2003. E. coli counts were not significantly different in samples taken at 5-m intervals from 0-40 M inland (P = 0.25). Neither E. coli nor enterococci mean counts showed any correlation or differences between the two beaches studied. In laboratory experiments, E. coli readily grew in sand supplemented with lake plankton, suggesting that in situ E. coli growth may occur when temperature and natural organic sources are adequate. Of the 114 sand enterococci isolates tested, positive species identification was obtained for only 52 (46%), with E. faecium representing the most dominant species (92%). Genetic characterization by ribotyping revealed no distinct genotypic pattern (s) for E. coli, suggesting that the sand population was rather a mixture of numerous strains (genotypes). These findings indicate that E. coli and enterococci can occur and persist for extended periods in backshore sand at the groundwater table. Although this study was limited to two beaches of southern Lake Michigan, similar findings can be expected at other temperate freshwater beaches. The long-term persistence of these bacteria, perhaps independent of pollution events, complicates their use as indicator organisms. Further, backshore sand at the water table may act as a reservoir for these bacteria and potentially for human pathogens. ?? IWA Publishing 2006.
2013-01-01
Background Lactose intolerance is a common health concern causing gastrointestinal symptoms and avoidance of dairy products by afflicted individuals. Since milk is a primary source of calcium and vitamin D, lactose intolerant individuals often obtain insufficient amounts of these nutrients which may lead to adverse health outcomes. Production of lactose-free milk can provide a solution to this problem, although it requires use of lactase from microbial sources and increases potential for contamination. Use of thermostable lactase enzymes can overcome this issue by functioning under pasteurization conditions. Results A thermostable β-glucosidase gene from Pyrococcus furiosus was cloned in frame with the Saccharomyces cerecisiae a-factor secretory signal and expressed in Pichia pastoris strain X-33. The recombinant enzyme was purified by a one-step method of weak anion exchange chromatography. The optimum temperature and pH for this β-glucosidase activity was 100°C and pH 6.0, respectively. The enzyme activity was not significantly inhibited by Ca2+. We tested the additive amount, hydrolysis time, and the influence of glucose on the enzyme during pasteurization and found that the enzyme possessed a high level of lactose hydrolysis in milk that was not obviously influenced by glucose. Conclusions The thermostablity of this recombinant β-glucosidase, combined with its neutral pH activity and favorable temperature activity optima, suggest that this enzyme is an ideal candidate for the hydrolysis of lactose in milk, and it would be suitable for application in low-lactose milk production during pasteurization. PMID:24053641
Zhou, Jing; Chen, Yan; Wang, Ying; Gao, Xia; Qu, Ding; Liu, Congyan
2013-12-24
The aim of this study was to compare the significance of the intestinal hydrolysis of prenylated flavonoids in Herba Epimedii by an intestinal enzyme and flora. Flavonoids were incubated at 37 °C with rat intestinal enzyme and intestinal flora. HPLC-UV was used to calculate the metabolic rates of the parent drug in the incubation and LC/MS/MS was used to determine the chemical structures of metabolites generated by different flavonoid glycosides. Rates of flavonoid metabolism by rat intestinal enzyme were quicker than those of intestinal flora. The sequence of intestinal flora metabolic rates was icariin>epimedin B>epimedin A>epimedin C>baohuoside I, whereas the order of intestinal enzyme metabolic rates was icariin>epimedin A>epimedin C>epimedin B>baohuoside I. Meanwhile, the LC/MS/MS graphs showed that icariin produced three products, epimedin A/B/C had four and baohuoside I yielded one product in incubations of both intestinal enzyme and flora, which were more than the results of HPLC-UV due to the fact LC/MS/MS has lower detectability and higher sensitivity. Moreover, the outcomes indicated that the rate of metabolization of flavonoids by intestinal enzyme were faster than those of intestinal flora, which was consistent with the HPLC-UV results. In conclusion, the metabolic pathways of the same components by intestinal flora and enzyme were the same. What's more, an intestinal enzyme such as lactase phlorizin hydrolase exhibited a more significant metabolic role in prenylated flavonoids of Herba Epimedi compared with intestinal flora.
Detecting and characterizing genomic signatures of positive selection in global populations.
Liu, Xuanyao; Ong, Rick Twee-Hee; Pillai, Esakimuthu Nisha; Elzein, Abier M; Small, Kerrin S; Clark, Taane G; Kwiatkowski, Dominic P; Teo, Yik-Ying
2013-06-06
Natural selection is a significant force that shapes the architecture of the human genome and introduces diversity across global populations. The question of whether advantageous mutations have arisen in the human genome as a result of single or multiple mutation events remains unanswered except for the fact that there exist a handful of genes such as those that confer lactase persistence, affect skin pigmentation, or cause sickle cell anemia. We have developed a long-range-haplotype method for identifying genomic signatures of positive selection to complement existing methods, such as the integrated haplotype score (iHS) or cross-population extended haplotype homozygosity (XP-EHH), for locating signals across the entire allele frequency spectrum. Our method also locates the founder haplotypes that carry the advantageous variants and infers their corresponding population frequencies. This presents an opportunity to systematically interrogate the whole human genome whether a selection signal shared across different populations is the consequence of a single mutation process followed subsequently by gene flow between populations or of convergent evolution due to the occurrence of multiple independent mutation events either at the same variant or within the same gene. The application of our method to data from 14 populations across the world revealed that positive-selection events tend to cluster in populations of the same ancestry. Comparing the founder haplotypes for events that are present across different populations revealed that convergent evolution is a rare occurrence and that the majority of shared signals stem from the same evolutionary event. Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.
First dairying in green Saharan Africa in the fifth millennium BC.
Dunne, Julie; Evershed, Richard P; Salque, Mélanie; Cramp, Lucy; Bruni, Silvia; Ryan, Kathleen; Biagetti, Stefano; di Lernia, Savino
2012-06-20
In the prehistoric green Sahara of Holocene North Africa-in contrast to the Neolithic of Europe and Eurasia-a reliance on cattle, sheep and goats emerged as a stable and widespread way of life, long before the first evidence for domesticated plants or settled village farming communities. The remarkable rock art found widely across the region depicts cattle herding among early Saharan pastoral groups, and includes rare scenes of milking; however, these images can rarely be reliably dated. Although the faunal evidence provides further confirmation of the importance of cattle and other domesticates, the scarcity of cattle bones makes it impossible to ascertain herd structures via kill-off patterns, thereby precluding interpretations of whether dairying was practiced. Because pottery production begins early in northern Africa the potential exists to investigate diet and subsistence practices using molecular and isotopic analyses of absorbed food residues. This approach has been successful in determining the chronology of dairying beginning in the 'Fertile Crescent' of the Near East and its spread across Europe. Here we report the first unequivocal chemical evidence, based on the δ(13)C and Δ(13)C values of the major alkanoic acids of milk fat, for the adoption of dairying practices by prehistoric Saharan African people in the fifth millennium bc. Interpretations are supported by a new database of modern ruminant animal fats collected from Africa. These findings confirm the importance of 'lifetime products', such as milk, in early Saharan pastoralism, and provide an evolutionary context for the emergence of lactase persistence in Africa.
Esteves, Francisco; Gaspar, Jorge; Tavares, Adélcia; Moser, Inês; Antunes, Francisco; Mansinho, Kamal; Matos, Olga
2010-03-01
Pneumocystis jirovecii pneumonia (PcP) is an important opportunistic infection among immunocompromised patients. Genetic characterization of P. jirovecii isolated from HIV-positive patients, based on identification of multiple nucleotide sequences at eight distinct loci, was achieved by using PCR with DNA sequencing and RFLP. The present study showed that the mitochondrial large-subunit rRNA (mtLSU rRNA), the cytochrome b (CYB), the superoxide dismutase (SOD), the beta-tubulin (beta-tub), the dihydrofolate reductase (DHFR) and the dihydropteroate synthase (DHPS) loci sequences were more variable and therefore giving additional information than the thioredoxin reductase (Trr1) and the thymidylate synthase (TS) genes. Genotyping at those six most informative loci enabled the identification of 48 different P. jirovecii multilocus genotypes (MLGs). Significant statistical associations between infecting P. jirovecii genotypes and patients' age groups or PcP clinical status were found. Also, mtLSU rRNA sequences and specific genotypes from other three loci (CYB, SOD, and DHFR) were statistically associated. The results suggested large recombination between most P. jirovecii MLGs. However, one MLG occurred at a higher frequency than would be expected according to panmictic expectations, suggesting linkage disequilibrium and clonal propagation. The persistence of this specific MLG may be a consequence of clonal reproduction of this successful genotypic array in a P. jirovecii population with epidemic structure. The present study provided the description of multiple genomic regions of P. jirovecii, improving the understanding of genetic variability and frequency distribution of polymorphic genotypes, and exploring the criteria of clonality by testing over-representation of MLGs.
Weinberg, Adriana; Song, Lin-Ye; Saah, Alfred; Brown, Martha; Moscicki, Anna B.; Meyer, William A.; Bryan, Janine; Levin, Myron J.
2012-01-01
Objectives. To characterize the immunogenicity of a quadrivalent human papillomavirus vaccine (QHPV) in human immunodeficiency virus (HIV)–infected children, we studied their immune responses to 3 or 4 doses. Methods. HIV-infected children aged 7–12 years with a CD4 cell percentage of ≥15% of lymphocytes, received 3 doses of QHPV with or without a fourth dose after 72 weeks. Type-specific and cross-reactive antibodies and cell-mediated immunity were measured. Results. Type-specific antibodies to HPV6, 11, and 16 were detected in 100% and ≥94% of children at 4 and 72 weeks, respectively, after the third QHPV dose. Corresponding numbers for HPV18 were 97% and 76%, respectively. A fourth QHPV dose increased seropositivity to ≥96% for all vaccine genotypes. Four weeks after the third QHPV dose, 67% of vaccinees seroconverted to HPV31, an HPV16-related genotype not in the vaccine; 69% and 39% of vaccinees developed mucosal HPV16 and 18 immunoglobulin G antibodies, respectively; and 60% and 52% of vaccinees developed cytotoxic T lymphocytes (CTLs) for HPV16 and 31, respectively. Conclusions. Three QHPV doses generated robust and persistent antibodies to HPV6, 11, and 16 but comparatively weaker responses to HPV18. A fourth dose increased antibodies against all vaccine genotypes in an anamnestic fashion. CTLs and mucosal antibodies against vaccine genotypes, as well as cross-reactive antibodies and CTL against nonvaccine genotypes, were detected. PMID:22859825
Guo, Renhua; Zhang, Zhihong; Xu, Hao; Yang, Chao; Zhu, Yi
2013-01-01
Aim To evaluate the impact of the Janus kinase 2 single nucleotide polymorphisms (SNPs) on gastric cancer risk. Methods In this hospital-based, case–control study, the genotypes were identified by polymerase chain reaction–restriction fragment length polymorphism protocols in 661 individuals (359 gastric cancer patients and 302 age and sex matched cancer-free controls). Results Both the frequency of A allele in rs2230724 and G allele in rs1887427 were more frequent in patients with gastric cancer (P = 0.013 and 0.001, respectively). Compared with the common genotype, subjects with the (AG+AA) genotypes of rs2230724 and the (AG+GG) genotypes of rs1887427 had a 59% and 98% increased risk of developing gastric cancer, respectively (P = 0.010, adjusted OR = 1.59, 95% CI = 1.12–2.27; P<0.001, adjusted OR = 1.98, 95% CI = 1.39–2.81, respectively). Further stratified analysis showed that the association between the risk of gastric cancer and the rare genotypes of rs2230724 were more profound in the subgroups of elder individuals (>56 years), males, nonsmokers and urban subjects, while the association between the risk and the rare genotypes of rs1887427 persisted in subgroups of younger individuals (≤56 years), males, nonsmokers and both of rural and urban subjects. Conclusion The JAK2 gene rs2230724 and rs1887427 polymorphisms are associated with an increased risk of gastric cancer in a Chinese Han population. PMID:23717640
Kashoma, Isaac P.; Kumar, Anand; Sanad, Yasser M.; Gebreyes, Wondwossen; Kazwala, Rudovick R.; Garabed, Rebecca
2014-01-01
Abstract Poultry are recognized as a main reservoir of Campylobacter spp. However, longitudinal studies investigating the persistence of Campylobacter on commercial meat turkeys are rare. The objectives of this study were to determine the prevalence, antimicrobial susceptibility, and persistence of genotypically related strains of Campylobacter spp. recovered from three commercial turkey farms in Ohio belonging to a single producer. Eight hundred ten samples were collected from birds aged 1 week to slaughter, consisting of 750 fecal droppings and 60 ceca at slaughter. Overall Campylobacter prevalence was 55.9%. Multiplex polymerase chain reaction (PCR) confirmed 72.3% of all isolates as C. coli, 5.3% as C. jejuni, 10.6% as both, and 11.9% as other Campylobacter spp. PCR restriction fragment length polymorphism of the flaA gene subtyping detected 70 types—62 for C. coli and 8 for C. jejuni isolates—with most (80%) of flaA-types constituting farm homogeneous groups. Multilocus sequence typing of 99 selected Campylobacter isolates resulted in 23 sequence types (STs), consisting of 8 STs for C. jejuni and 15 STs for C. coli isolates. Six novel STs—four for C. jejuni and two—for C. coli, were detected. In a subset of isolates (n=98) tested for antimicrobial resistance, the most common resistance was to tetracycline (95%), followed by azithromycin (43%), while 42% and 18% of the isolates were resistant to ciprofloxacin and erythromycin, respectively. All isolates were susceptible to florfenicol. C. coli isolates displayed a higher proportion of resistance than C. jejuni to most antimicrobials. This study highlights the high prevalence, genotypic diversity, and antimicrobial resistance of Campylobacter spp. in commercial turkey from farm to slaughter. PMID:25184688
Gama, Bianca E.; Emmel, Vanessa E.; Oliveira-Silva, Michelle; Gutiyama, Luciana M.; Arcuri, Leonardo; Colares, Marta; de Cássia Tavares, Rita; Bouzas, Luis F.; Abdelhay, Eliana; Hassan, Rocio
2017-01-01
Background Parvovirus B19 (B19V) is a common human pathogen, member of the family Parvoviridae. Typically, B19V has been found to infect erythroid progenitors and cause hematological disorders, such as anemia and aplastic crisis. However, the persistence of genomic deoxyribonucleic acid (DNA) has been demonstrated in tonsils, liver, skin, brain, synovial, and testicular tissues as well as bone marrow, for both symptomatic and asymptomatic subjects. Although the molecular and cellular mechanisms of persistence remain undefined, it raises questions about potential virus transmissibility and its effects in the context of allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients. Methods With this aim, we retrospectively screened allogeneic stem cell donors from 173 patients admitted for allo-HSCT from January 2008 to May 2013 using a seminested polymerase chain reaction approach. Results We found 8 positive donor samples, yielding a 4.6% of parvovirus prevalence (95% confidence interval, 2.36-8.85). Pre- and post-HSCT samples (n = 51) from the 8 recipients of the positive donors were also investigated, and 1 case exhibited B19V DNA in the post-HSCT follow-up (D + 60). Direct DNA sequencing was performed to determine the genotype of isolates and classification, performed by phylogenetic reconstruction, showed a predominance of genotype 1a, whereas the rare genotype 3b was detected in 2 additional patients. By molecular cloning, different B19V 1a substrains polymorphisms were evidenced in the single case in which donor and its recipient were B19V+. Conclusions Our results suggest that HSCT allografts are not a main source for B19V transmission, pointing to potential events of reinfection or endogenous viral reactivation. PMID:29184906
Gama, Bianca E; Emmel, Vanessa E; Oliveira-Silva, Michelle; Gutiyama, Luciana M; Arcuri, Leonardo; Colares, Marta; de Cássia Tavares, Rita; Bouzas, Luis F; Abdelhay, Eliana; Hassan, Rocio
2017-11-01
Parvovirus B19 (B19V) is a common human pathogen, member of the family Parvoviridae. Typically, B19V has been found to infect erythroid progenitors and cause hematological disorders, such as anemia and aplastic crisis. However, the persistence of genomic deoxyribonucleic acid (DNA) has been demonstrated in tonsils, liver, skin, brain, synovial, and testicular tissues as well as bone marrow, for both symptomatic and asymptomatic subjects. Although the molecular and cellular mechanisms of persistence remain undefined, it raises questions about potential virus transmissibility and its effects in the context of allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients. With this aim, we retrospectively screened allogeneic stem cell donors from 173 patients admitted for allo-HSCT from January 2008 to May 2013 using a seminested polymerase chain reaction approach. We found 8 positive donor samples, yielding a 4.6% of parvovirus prevalence (95% confidence interval, 2.36-8.85). Pre- and post-HSCT samples (n = 51) from the 8 recipients of the positive donors were also investigated, and 1 case exhibited B19V DNA in the post-HSCT follow-up (D + 60). Direct DNA sequencing was performed to determine the genotype of isolates and classification, performed by phylogenetic reconstruction, showed a predominance of genotype 1a, whereas the rare genotype 3b was detected in 2 additional patients. By molecular cloning, different B19V 1a substrains polymorphisms were evidenced in the single case in which donor and its recipient were B19V+. Our results suggest that HSCT allografts are not a main source for B19V transmission, pointing to potential events of reinfection or endogenous viral reactivation.
Visvalingam, J; Ells, T C; Yang, X
2017-12-01
To examine the influence of meat plant Escherichia coli and Salmonella sp. isolates on E. coli O157 biofilm formation. Biofilm formation was quantified by crystal violet staining (A 570 nm ) and viable cell numbers for up to 6 days at 15°C. All five persistent E. coli genotypes formed strong biofilms when cultured alone or co-cultured with E. coli O157, with A 570 nm values reaching ≥4·8 at day 4, while only two of five nonpersistent genotypes formed such biofilms. For E. coli O157:H7 co-culture biofilms with E. coli genotypes 136 and 533, its numbers were ≥1·5 and ≥1 log CFU per peg lower than those observed for its mono-culture biofilm at days 2 and 4, respectively. The number of E. coli O157:NM in similar co-culture biofilms was 1 log CFU per peg lower than in its mono-culture biofilm at day 4 and 6, respectively. Salmonella sp. lowered the number of E. coli O157:NM by 0·5 log unit, once, at day 6. Generic E. coli may outcompete E. coli O157 strains while establishing biofilms. Findings advance knowledge regarding inter-strain competition for a similar ecological niche and may aid development of biocontrol strategies for E. coli O157 in food processing environments. © 2017 Her Majesty the Queen in Right of Canada. Journal of Applied Microbiology © 2017 The Society for Applied Microbiology Reproduced with the permission of the Minister of the Department of Agriculture and Agri-Food Canada.
Lu, Zhiming; Zhang, Bingchang; Chen, Shijun; Gai, Zhongtao; Feng, Zhaolei; Liu, Xiangdong; Liu, Yiqing; Wen, Xin; Li, Li; Jiao, Yulian; Ma, Chunyan; Shao, Song; Cui, Xiangfa; Chen, Guojian; Li, Jianfeng; Zhao, Yueran
2008-12-01
Killer immunoglobulin-like receptor (KIR) genes can regulate the activation of NK and T cells upon interaction with HLA class I molecules. Hepatitis B virus (HBV) infection has been regarded as a multi-factorial disorder disease. Previous studies revealed that KIRs were involved in HCV and HIV infection or clearance. The aim of this study was to explore the possibility of the inheritance of KIR genotypes and haplotypes as a candidate for susceptibility to persistent HBV infection or HBV clearance. The sequence specific primer polymerase chain reaction (SSP-PCR) was employed to identify the KIR genes and pseudogenes in 150 chronic hepatitis B (CHB) patients, 251 spontaneously recovered (SR) controls, and 412 healthy controls. The frequencies of genotype G, M, FZ1 increased in CHB patients compared with healthy control subjects. The frequency of genotype AH was higher in SR controls than that in both CHB patients and healthy controls. The carriage frequencies of genotype G and AH were higher; while, the frequencies of AF and AJ were lower in SR controls than those in healthy control subjects. The frequency of A haplotype was lower, whereas, the frequency of B haplotype was higher in CHB patients and SR controls than those in healthy controls. In healthy controls, haplotype 4 was found lower compared with that in CHB patients and SR controls and the frequency of haplotype 5 was higher in SR controls than that in other two groups. Based on these findings, it seems that the genotypes M and FZ1 are HBV susceptive genotypes; AH, on the other hand, may be protective genotypes that facilitate the clearance of HBV. It appears that the haplotype 4 is HBV susceptive haplotype, whereas, haplotype 5 may be the protective haplotype that facilitates the clearance of HBV.
Occurrence and genetic diversity of Arcobacter butzleri in an artisanal dairy plant in Italy.
Giacometti, Federica; Lucchi, Alex; Manfreda, Gerardo; Florio, Daniela; Zanoni, Renato Giulio; Serraino, Andrea
2013-11-01
The present study aimed to investigate the presence, distribution, and persistence of Arcobacter spp. in an artisanal dairy plant and to test the isolates to determine their different genotypes in the processing plant and in foods. Samples were collected in an artisanal cheese factory on four occasions between October and December 2012. Food samples (raw milk, ricotta cheese, mozzarella cheese, and conditioning liquid), water samples, and environmental samples were analyzed by the culture method; isolates were identified by multiplex PCR and genotyped by pulsed-field gel electrophoresis (PFGE) analysis. Arcobacter butzleri was isolated from 29 out of 59 samples (46.6%), 22 of which were from environmental samples and 7 of which were from food samples. Cluster analysis divided the strains into 47 PFGE patterns: 14 PFGE clusters and 33 unique types. Our findings indicate that the plant harbored numerous A. butzleri pulsotypes and that the manual cleaning and sanitation in the studied dairy plant do not effectively remove Arcobacter. The recurrent isolation of A. butzleri suggests that the environmental conditions in the dairy plant constitute a good ecological niche for the colonization of this microorganism. In some cases, the presence of indistinguishable strains isolated from the same facilities on different sampling days showed that these strains were persistent in the processing environment.
Rodríguez, Ana Cecilia; Burk, Robert D.; Herrero, Rolando; Wacholder, Sholom; Hildesheim, Allan; Morales, Jorge; Rydzak, Greg; Schiffman, Mark
2011-01-01
Background. Detailed descriptions of long-term persistence of human papillomavirus (HPV) in the absence of cervical precancer are lacking. Methods. In a large, population-based natural study conducted in Guanacaste, Costa Rica, we studied a subset of 810 initially HPV-positive women with ≥3 years of active follow-up with ≥3 screening visits who had no future evidence of cervical precancer. Cervical specimens were tested for >40 HPV genotypes using a MY09/11 L1-targeted polymerase chain reaction method. Results. Seventy-two prevalently-detected HPV infections (5%) in 58 women (7%) persisted until the end of the follow-up period (median duration of follow-up, 7 years) without evidence of cervical precancer. At enrollment, women with long-term persistence were more likely to have multiple prevalently-detected HPV infections (P <.001) than were women who cleared their baseline HPV infections during follow-up. In a logistic regression model, women with long-term persistence were more likely than women who cleared infections to have another newly-detected HPV infection detectable at ≥3 visits (odds ratio, 2.6; 95% confidence interval, 1.2–5.6). Conclusions. Women with long-term persistence of HPV infection appear to be generally more susceptible to other HPV infections, especially longer-lasting infections, than are women who cleared their HPV infections. PMID:21343148
Glucocorticoid Receptor Polymorphisms and Outcomes in Pediatric Septic Shock.
Cvijanovich, Natalie Z; Anas, Nick; Allen, Geoffrey L; Thomas, Neal J; Bigham, Michael T; Weiss, Scott L; Fitzgerald, Julie; Checchia, Paul A; Meyer, Keith; Quasney, Michael; Gedeit, Rainer; Freishtat, Robert J; Nowak, Jeffrey; Raj, Shekhar S; Gertz, Shira; Grunwell, Jocelyn R; Opoka, Amy; Wong, Hector R
2017-04-01
Polymorphisms of the glucocorticoid receptor gene are associated with outcome and corticosteroid responsiveness among patients with inflammatory disorders. We conducted a candidate gene association study to test the hypothesis that these polymorphisms are associated with outcome and corticosteroid responsiveness among children with septic shock. We genotyped 482 children with septic shock for the presence of two glucocorticoid receptor polymorphisms (rs56149945 and rs41423247) associated with increased sensitivity and one glucocorticoid receptor polymorphism (rs6198) associated with decreased sensitivity to corticosteroids. The primary outcome variable was complicated course, defined as 28-day mortality or the persistence of two or more organ failures 7 days after a septic shock diagnosis. We used logistic regression to test for an association between corticosteroid exposure and outcome, within genotype group, and adjusted for illness severity. Multiple PICUs in the United States. Standard care. There were no differences in outcome when comparing the various genotype groups. Among patients homozygous for the wild-type glucocorticoid receptor allele, corticosteroids were independently associated with increased odds of complicated course (odds ratio, 2.30; 95% CI, 1.01-5.21; p = 0.047). Based on these glucocorticoid receptor polymorphisms, we could not detect a beneficial effect of corticosteroids among any genotype group. Among children homozygous for the wild-type allele, corticosteroids were independently associated with increased odds of poor outcome.
Molecular Epidemiology of Rhinovirus Detections in Young Children
Howard, Leigh M.; Johnson, Monika; Gil, Ana I.; Griffin, Marie R.; Edwards, Kathryn M.; Lanata, Claudio F.; Williams, John V.; Grijalva, Carlos G.
2016-01-01
Background. Human rhinoviruses (HRVs) are frequently detected in children with acute respiratory illnesses (ARIs) but also in asymptomatic children. We compared features of ARI with HRV species (A, B, C) and determined genotypes associated with repeated HRV detections within individuals. Methods. We used clinical data and respiratory samples obtained from children <3 years old during weekly active household-based surveillance. A random subset of samples in which HRV was detected from individuals during both ARI and an asymptomatic period within 120 days of the ARI were genotyped. Features of ARI were compared among HRV species. Concordance of genotype among repeated HRV detections within individuals was assessed. Results. Among 207 ARI samples sequenced, HRV-A, HRV-B, and HRV-C were detected in 104 (50%), 20 (10%), and 83 (40%), respectively. Presence of fever, decreased appetite, and malaise were significantly higher in children with HRV-B. When codetections with other viruses were excluded (n = 155), these trends persisted, but some did not reach statistical significance. When 58 paired sequential HRV detections during asymptomatic and ARI episodes were sequenced, only 9 (16%) were identical genotypes of HRV. Conclusions. Clinical features may differ among HRV species. Repeated HRV detections in young children frequently represented acquisition of new HRV strains. PMID:26900577
Kaliff, Malin; Sorbe, Bengt; Mordhorst, Louise Bohr; Helenius, Gisela; Karlsson, Mats G; Lillsunde-Larsson, Gabriella
2018-04-10
Cervical cancer (CC) is one of the most common cancers in women and virtually all cases of CC are a result of a persistent infection of human papillomavirus (HPV). For disease detected in early stages there is curing treatment but when diagnosed late with recurring disease and metastasis there are limited possibilities. Here we evaluate HPV impact on treatment resistance and metastatic disease progression. Prevalence and distribution of HPV genotypes and HPV16 variants in a Swedish CC patient cohort (n=209) was evaluated, as well as HPV influence on patient prognosis. Tumor samples suitable for analysis (n=204) were genotyped using two different real-time PCR methods. HPV16 variant analysis was made using pyrosequencing. Results showed that HPV prevalence in the total series was 93%. Of the HPV-positive samples, 13% contained multiple infections, typically with two high-risk HPV together. Primary cure rate for the complete series was 95%. Recurrence rate of the complete series was 28% and distant recurrences were most frequent (20%). Patients with tumors containing multiple HPV-strains and particularly HPV genotypes belonging to the alpha 7 and 9 species together had a significantly higher rate of distant tumor recurrences and worse cancer-specific survival rate.
Saffold Virus Type 3 (SAFV-3) Persists in HeLa Cells
Himeda, Toshiki; Hosomi, Takushi; Okuwa, Takako; Muraki, Yasushi; Ohara, Yoshiro
2013-01-01
Saffold virus (SAFV) was identified as a human cardiovirus in 2007. Although several epidemiological studies have been reported, they have failed to provide a clear picture of the relationship between SAFV and human diseases. SAFV genotype 3 has been isolated from the cerebrospinal fluid specimen of patient with aseptic meningitis. This finding is of interest since Theiler’s murine encephalomyelitis virus (TMEV), which is the closely related virus, is known to cause a multiple sclerosis-like syndrome in mice. TMEV persistently infects in mouse macrophage cells in vivo and in vitro, and the viral persistence is essential in TMEV-induced demyelinating disease. The precise mechanism(s) of SAFV infection still remain unclear. In order to clarify the SAFV pathogenicity, in the present study, we studied the possibilities of the in vitro persistent infection of SAFV. The two distinct phenotypes of HeLa cells, HeLa-N and HeLa-R, were identified. In these cells, the type of SAFV-3 infection was clearly different. HeLa-N cells were lyticly infected with SAFV-3 and the host suitable for the efficient growth. On the other hand, HeLa-R cells were persistently infected with SAFV-3. In addition, the SAFV persistence in HeLa-R cells is independent of type I IFN response of host cells although the TMEV persistence in mouse macrophage cells depends on the response. Furthermore, it was suggested that SAFV persistence may be influenced by the expression of receptor(s) for SAFV infection on the host cells. The present findings on SAFV persistence will provide the important information to encourage the research of SAFV pathogenicity. PMID:23308162
Morrow, E H; Leijon, A; Meerupati, A
2008-11-01
Spermatozoa are the most diverse of all animal cells. Variation in size alone is enormous and yet there are still no clear evolutionary explanations that can account for such diversity. The basic genetics of sperm form is also poorly understood, although sperm size is known to have a strong genetic component. Here, using hemiclonal analysis of Drosophila melanogaster, we demonstrate that there is not only a significant additive genetic component contributing to phenotypic variation in sperm length but also a significant environmental effect. Furthermore, the plasticity of sperm size has a significant genetic component to it (a genotype x environment interaction). A genotype x environment interaction could contribute to the maintenance of the substantial genetic variation in this trait and thereby explain the persistent inter-male differences in sperm size seen in numerous taxa. We suggest that the low conditional dependence and high heritability but low evolvability (the coefficient of additive genetic variation) of sperm length is more consistent with a history of stabilizing selection rather than either sexual selection or strong directional selection.
Velay, A; Jeulin, H; Eschlimann, M; Malvé, B; Goehringer, F; Bensenane, M; Frippiat, J-P; Abraham, P; Ismail, A M; Murray, J M; Combet, C; Zoulim, F; Bronowicki, J-P; Schvoerer, E
2016-05-01
For hepatitis B virus (HBV)-related chronic infection under treatment by nucleos(t)ide analogues (NUCs), HBsAg clearance is the ultimate therapeutic goal but very infrequent. We investigated how HBV envelope protein variability could lead to differential HBsAg clearance on NUCs. For 12 HBV genotype D patients receiving NUCs, six resolvers (HBsAg clearance) were compared to six matched nonresolvers (HBsAg persistence). PreS/S amino acid (aa) sequences were analysed with bioinformatics to predict HBV envelope antigenicity and aa covariance. To enrich our analyses on very rare resolvers, these were compared with other HBV genotype D strains in three characterized clinical cohorts including common chronically infected patients. The sT125M+sP127T combination was observed in four nonresolvers of six, corroborated by aa covariance analysis, associated with a lower predicted antigenicity than sT125T+sP127P. Concordant features within this HBV key functional domain, at positions 125 and 127, were reported from two of the three comparative cohorts. In our hands, a lower ELISA reactivity of HBV-vaccinated mice sera was observed against the sT125M mutant. In the S gene, 56 aa changes in minor variants were detected in non-resolvers, mainly in the major hydrophilic region, vs 28 aa changes in resolvers. Molecular features in patients showing HBsAg persistence on NUCs argue in favour of a different aa pattern in the HBV S gene compared to those showing HBsAg clearance. In nonresolvers, a decrease in HBs 'a' determinant antigenicity and more frequent mutations in the S gene suggest a role for the HBV envelope characteristics in HBsAg persistence. © 2016 John Wiley & Sons Ltd.
Muller, Christopher L; Anacker, Allison MJ; Rogers, Tiffany D; Goeden, Nick; Keller, Elizabeth H; Forsberg, C Gunnar; Kerr, Travis M; Wender, Carly LA; Anderson, George M; Stanwood, Gregg D; Blakely, Randy D; Bonnin, Alexandre; Veenstra-VanderWeele, Jeremy
2017-01-01
Biomarker, neuroimaging, and genetic findings implicate the serotonin transporter (SERT) in autism spectrum disorder (ASD). Previously, we found that adult male mice expressing the autism-associated SERT Ala56 variant have altered central serotonin (5-HT) system function, as well as elevated peripheral blood 5-HT levels. Early in gestation, before midbrain 5-HT projections have reached the cortex, peripheral sources supply 5-HT to the forebrain, suggesting that altered maternal or placenta 5-HT system function could impact the developing embryo. We therefore used different combinations of maternal and embryo SERT Ala56 genotypes to examine effects on blood, placenta and embryo serotonin levels and neurodevelopment at embryonic day E14.5, when peripheral sources of 5-HT predominate, and E18.5, when midbrain 5-HT projections have reached the forebrain. Maternal SERT Ala56 genotype was associated with decreased placenta and embryonic forebrain 5-HT levels at E14.5. Low 5-HT in the placenta persisted, but forebrain levels normalized by E18.5. Maternal SERT Ala56 genotype effects on forebrain 5-HT levels were accompanied by a broadening of 5-HT-sensitive thalamocortical axon projections. In contrast, no effect of embryo genotype was seen in concepti from heterozygous dams. Blood 5-HT levels were dynamic across pregnancy and were increased in SERT Ala56 dams at E14.5. Placenta RNA sequencing data at E14.5 indicated substantial impact of maternal SERT Ala56 genotype, with alterations in immune and metabolic-related pathways. Collectively, these findings indicate that maternal SERT function impacts offspring placental 5-HT levels, forebrain 5-HT levels, and neurodevelopment. PMID:27550733
Muñoz-Alía, Miguel Angel; Casasnovas, José M; Celma, María Luisa; Carabaña, Juan; Liton, Paloma B; Fernandez-Muñoz, Rafael
2017-05-15
Measles virus (MV) remains a leading cause of vaccine-preventable deaths in children. Protection against MV is associated with neutralizing antibodies that preferentially recognize the viral hemagglutinin (MV-H), and to a lesser extent, the fusion protein (MV-F). Although MV is serologically monotypic, 24 genotypes have been identified. Here we report three neutralization epitopes conserved in the more prevalent circulating MV genotypes, two located in the MV-H receptor binding site (RBS) (antigenic site III) and a third in MV-H/MV-F interphase (antigenic site Ia) which are essential for MV multiplication. In contrast, two MV-H neutralization epitopes, showed a genotype-specific neutralization escape due to a single amino acid change, that we mapped in the "noose" antigenic site, or an enhanced neutralization epitope (antigenic site IIa). The monoclonal antibody (mAb) neutralization potency correlated with its binding affinity and was mainly driven by kinetic dissociation rate (k off ). We developed an immunoassay for mAb binding to MV-H in its native hetero-oligomeric structure with MV-F on the surface of a MV productive steady-state persistently infected (p.i.) human cell lines, and a competitive-binding assay with serum from individuals with past infection by different MV genotypes. Binding assays revealed that a broad neutralization epitope, in RBS antigenic site, a genotype specific neutralization epitopes, in noose and IIa sites, were immunogenic in natural infection and vaccination and may elicit long-lasting humoral immunity that might contribute to explain MV immunogenic stability. These results support the design of improved measles vaccines, broad-spectrum prophylactic or therapeutic antibodies and MV-used in oncolytic therapies. Copyright © 2017 Elsevier B.V. All rights reserved.
The Role of Clonal Interference in the Evolutionary Dynamics of Plasmid-Host Adaptation
Hughes, Julie M.; Lohman, Brian K.; Deckert, Gail E.; Nichols, Eric P.; Settles, Matt; Abdo, Zaid; Top, Eva M.
2012-01-01
ABSTRACT Promiscuous plasmids replicate in a wide range of bacteria and therefore play a key role in the dissemination of various host-beneficial traits, including antibiotic resistance. Despite the medical relevance, little is known about the evolutionary dynamics through which drug resistance plasmids adapt to new hosts and thereby persist in the absence of antibiotics. We previously showed that the incompatibility group P-1 (IncP-1) minireplicon pMS0506 drastically improved its stability in novel host Shewanella oneidensis MR-1 after 1,000 generations under antibiotic selection for the plasmid. The only mutations found were those affecting the N terminus of the plasmid replication initiation protein TrfA1. Our aim in this study was to gain insight into the dynamics of plasmid evolution. Changes in stability and genotype frequencies of pMS0506 were monitored in evolving populations of MR-1 (pMS0506). Genotypes were determined by sequencing trfA1 amplicons from individual clones and by 454 pyrosequencing of whole plasmids from entire populations. Stability of pMS0506 drastically improved by generation 200. Many evolved plasmid genotypes with point mutations as well as in-frame and frameshift deletions and duplications in trfA1 were observed in all lineages with both sequencing methods. Strikingly, multiple genotypes were simultaneously present at high frequencies (>10%) in each population. Their relative abundances changed over time, but after 1,000 generations only one or two genotypes dominated the populations. This suggests that hosts with different plasmid genotypes were competing with each other, thus affecting the evolutionary trajectory. Plasmids can thus rapidly improve their stability, and clonal interference plays a significant role in plasmid-host adaptation dynamics. PMID:22761390
Garcia-R, Juan C; French, Nigel; Pita, Anthony; Velathanthiri, Niluka; Shrestha, Rima; Hayman, David
2017-07-01
Cryptosporidiosis and giardiasis are recognized as significant enteric diseases due to their long-term health effects in humans and their economic impact in agriculture and medical care. Molecular analysis is essential to identify species and genotypes causing these infectious diseases and provides a potential tool for monitoring. This study uses information on species and genetic variants to gain insights into the geographical distribution and spatial patterns of Cryptosporidium and Giardia parasites. Here, we describe the population heterogeneity of genotypic groups within Cryptosporidium and Giardia present in New Zealand using gp60 and gdh markers to compare the observed variation with other countries around the globe. Four species of Cryptosporidium (C. hominis, C. parvum, C. cuniculus and C. erinacei) and one species of Giardia (G. intestinalis) were identified. These species have been reported worldwide and there are not unique Cryptosporidium gp60 subtype families and Giardia gdh assemblages in New Zealand, most likely due to high gene flow of historical and current human activity (travel and trade) and persistence of large host population sizes. The global analysis revealed that genetic variants of these pathogens are widely distributed. However, genetic variation is underestimated by data biases (e.g. neglected submission of sequences to genetic databases) and low sampling. New genotypes are likely to be discovered as sampling efforts increase according to accumulation prediction analyses, especially for C. parvum. Our study highlights the need for greater sampling and archiving of genotypes globally to allow comparative analyses that help understand the population dynamics of these protozoan parasites. Overall our study represents a comprehensive overview for exploring local and global protozoan genotype diversity and advances our understanding of the importance for surveillance and potential risk associated with these infectious diseases.
Serum vitamin C and other biomarkers differ by genotype of phase 2 enzyme genes GSTM1 and GSTT1123
Shaikh, Nishat; Jensen, Christopher D; Volberg, Vitaly; Holland, Nina
2011-01-01
Background: Glutathione S-transferases (GSTs) detoxify environmental chemicals and are involved in oxidative stress pathways. Deletion polymorphisms affect enzyme activities and have been associated with risk of disease. Objective: The objective was to clarify whether biomarkers of oxidation, antioxidation, inflammation, and nutritional factors differ by GST genotype in healthy adults. Design: Subjects (n = 383) consisted of nonsmokers and nonusers of antiinflammatory drugs and antioxidant vitamin supplements. Deletion polymorphisms of GSTM1 and GSTT1 were genotyped. F2-isoprostanes, malondialdehyde, C-reactive protein, serum vitamin C, carotenoids, tocopherols, and other nutritional factors were assessed. Results: The concentration of serum vitamin C was higher in persons with the inactive GSTM1-0 genotype (P = 0.006). This relation was unchanged after adjustment for age, sex, BMI, or dietary vitamin C. F2-isoprostanes and malondialdehyde were lower in the GSTM1-0 and GSTT1-0 groups, respectively, but significance was lost after control for serum vitamin C. The dual deletion, GSTM1-0/GSTT1-0 (n = 37), was associated with higher serum iron and total and LDL-cholesterol concentrations (all P < 0.01) and lower malondialdehyde concentrations, which persisted after adjustment for age, sex, BMI, and serum vitamin C. Carotenoids and α- and γ-tocopherols were not associated with either genotype. Conclusions: Oxidative stress and inflammation biomarkers differ by GST genotype, but serum vitamin C appears to be the most consistent factor. Examination of other relevant genes may be needed to understand the concentration and function of ascorbic acid in the GST enzyme system. This trial is registered at clinicaltrials.gov as NCT00079963. PMID:21813807
Differential impact of lactose/lactase phenotype on colonic microflora
Szilagyi, Andrew; Shrier, Ian; Heilpern, Debra; Je, Jung Sung; Park, Sunghoon; Chong, George; Lalonde, Catherine; Cote, Louis-Francois; Lee, Byong
2010-01-01
BACKGROUND: The ability to digest lactose divides the world’s population into two phenotypes that may be risk variability markers for several diseases. Prebiotic effects likely favour lactose maldigesters who experience lactose spilling into their colon. OBJECTIVE: To evaluate the effects of fixed-dose lactose solutions on fecal bifidobacteria and lactobacilli in digesters and maldigesters, and to determine whether the concept of a difference in ability to digest lactose is supported. METHODS: A four-week study was performed in 23 lactose mal-digesters and 18 digesters. Following two weeks of dairy food withdrawal, subjects ingested 25 g of lactose twice a day for two weeks. Stool bifidobacteria and lactobacilli counts pre- and postintervention were measured as the primary outcome. For secondary outcomes, total anaerobes, Enterobacteriaceae, beta-galactosidase and N-acetyl-beta-D-glucosaminidase activity in stool, as well as breath hydrogen and symptoms following lactose challenge tests, were measured. RESULTS: Lactose maldigesters had a mean change difference (0.72 log10 colony forming units/g stool; P=0.04) in bifidobacteria counts compared with lactose digesters. Lactobacilli counts were increased, but not significantly. Nevertheless, reduced breath hydrogen after lactose ingestion correlated with lactobacilli (r=−0.5; P<0.001). Reduced total breath hydrogen and symptom scores together, with a rise in fecal enzymes after intervention, were appropriate, but not significant. CONCLUSIONS: Despite failure to achieve full colonic adaptation, the present study provided evidence for a differential impact of lactose on microflora depending on genetic lactase status. A prebiotic effect was evident in lactose maldigesters but not in lactose digesters. This may play a role in modifying the mechanisms of certain disease risks related to dairy food consumption between the two phenotypes. PMID:20559580
Clinical Characteristics of Disaccharidase Deficiencies Among Children Undergoing Upper Endoscopy.
Cohen, Stanley A; Oloyede, Hannah; Gold, Benjamin D; Mohammed, Aminu; Elser, Heather E
2018-06-01
The epidemiology and clinical significance of disaccharidase deficiencies have not been thoroughly characterized. Recent work suggests at least genetic sucrase-isomaltase deficiency is more prevalent than previously believed. Because lactase deficiency (LD) is well described, the present study focuses on the clinical characteristics of children with disaccharidase deficiencies determined by esophagogastroduodenoscopy. Endoscopic records were reviewed from patients undergoing esophagogastroduodenoscopies with biopsies assayed for disaccharidase activity performed by 13 pediatric gastroenterologists during 5 years (2010-2014). Presenting symptoms, clinical and histological diagnosis, treatment, disaccharidase results, and demographic variables were obtained from medical and endoscopic records of those with maltase and sucrase deficiency (SD). Among 963 patients undergoing intestinal disaccharidase testing, 73 (7.6%) had SD on biopsy (enzyme activity <25 μmol · min · g). Thirty-four (34/73; 47%) had normal duodenal histology and are the focus of this report. Four patients had SD without LD. Pan-disaccharidase deficiency was observed in 24 patients when maltase and palatinase assays were obtained (n = 646), and 11 had SD + LD when just those 2 enzymes were analyzed (n = 317). Those with SD without LD were younger 4.6 ± 6.1 versus 14.1 ± 3.6 years and uniformly presented with diarrhea. Patients with pan-disaccharidase deficiency or SD + LD primarily reported abdominal pain (33/35; 94%), diarrhea (16/35; 46%), nausea (14/35; 40%); and poor weight gain/weight loss (10/35; 29%); constipation, flatulence, and bloating were also noted. Maltase deficiency is less common (8/963; 0.8%), presenting with similar symptoms. Genetic sucrase-isomaltase deficiency often occurs together with lactase or pan-disaccharide deficiency. Disaccharidase deficiency should be considered a potential cause of abdominal pain and/or diarrhea in children and adolescents.
De Vos, M; Huygelen, V; Van Raemdonck, G; Willemen, S; Fransen, E; Van Ostade, X; Casteleyn, C; Van Cruchten, S; Van Ginneken, C
2014-08-01
To test the hypothesis that a low molecular weight fraction of colostral whey could affect the morphology and barrier function of the small intestine, 30 3-d-old piglets (normal or low birth weight) were suckled (n = 5), artificially fed with milk formula (n = 5), or artificially fed with milk formula with a low molecular weight fraction of colostral whey (n = 5) until 10 d of age. The small intestine was sampled for histology (haematoxylin and eosin stain; anti-KI67 immunohistochemistry) and enzyme activities (aminopeptidase A, aminopeptidase N, dipeptidylpeptidase IV, lactase, maltase, and sucrase). In addition, intestinal permeability was evaluated via a dual sugar absorption test and via the measurement of occludin abundance. Artificially feeding of piglets reduced final BW (P < 0.001), villus height (P < 0.001), lactase (P < 0.001), and dipeptidylpeptidase IV activities (P < 0.07), whereas crypt depth (P < 0.001) was increased. No difference was observed with regard to the permeability measurements when comparing artificially fed with naturally suckling piglets. Supplementing piglets with the colostral whey fraction did not affect BW, enzyme activities, or the outcome of the dual sugar absorption test. On the contrary, the small intestines of supplemented piglets had even shorter villi (P = 0.001) than unsupplemented piglets and contained more occludin (P = 0.002). In conclusion, at 10 d of age, no differences regarding intestinal morphology and permeability measurements were observed between the 2 BW categories. In both weight categories, the colostral whey fraction affected the morphology of the small intestine but did not improve the growth performances or the in vivo permeability. These findings should be acknowledged when developing formulated milk for neonatal animals with the aim of improving the performance of low birth weight piglets.
Lactose intolerance and intestinal villi morphology in Thai people.
Thong-Ngam, D; Suwangool, P; Prempracha, J; Tangkijvanich, P; Vivatvekin, B; Sriratanabun, A
2001-08-01
To study the relationship of lactose intolerance and intestinal villi morphology in Thai people. Subjects for this study were patients with functional dyspepsia who had no history of milk allergy and underwent gastroduodenoscopy. Two mucosal biopsy specimens were taken from beyond the distal end of the second part of the duodenum. The specimens were carefully orientated and were graded according to the following scheme: group I: finger shaped villi; group II: mixed finger and leaf shaped villi; group III: clubbing or blunting shaped villi. All subjects were tested for lactose malabsorption by breath hydrogen analysis after consuming 50 gram lactose. Breath hydrogen concentration was analyzed in samples collected intermittently by end-expiratory technique. A rise in breath hydrogen concentration of 20 PPM over baseline was considered evidence of lactose malabsorption. The twenty-five subjects were twenty females (80.0%) and five males (20.0%) who ranged in age from 18 to 53 years (mean 31 +/- 8.29). Sixteen subjects belonged to the finger shaped villi group (64.0%), five to the mixed finger and leaf shaped villi, group (20.0%) and four to the clubbing or blunting shaped villi group (16.0%). Results of breath hydrogen excretion test identified the prevalence of lactose intolerance in 68 per cent of the subjects: 15/16 (93.75%) of group I; 1/5 (20.0%) of group II and 1/4 (25%) of group III respectively (P<0.001). The symptom of diarrhea after lactose loading was correlated well in patients who had positive breath hydrogen analysis. As shown in this study, the lactose intolerance is not related to intestinal villi morphology. It is implied that primary lactase deficiency is more common in Thai people than secondary lactase deficiency.
Infantile colic: a systematic review of medical and conventional therapies.
Hall, Belinda; Chesters, Janice; Robinson, Anske
2012-02-01
Infantile colic is a prevalent and distressing condition for which there is no proven standard therapy. The aim of this paper is to review medical and conventional treatments for infantile colic. A systematic literature review was undertaken of studies on medical and conventional interventions for infantile colic from 1980 to March 2009. The results and methodological rigour of included studies were analysed using the CONSORT (Consolidated Standards Of Reporting Trials) 2001 statement checklist and Centre for Evidence Based Medicine critical appraisal tools. Nineteen studies and two literature reviews were included for review. Pharmacological studies on Simethicone gave conflicting results and with Dicyclomine hydrochloride and Cimetropium bromide results were favourable but side effects were noted along with issues in study methodology. Some nutritional studies reported favourable results for the use of hydrolysed formulas in bottle-fed infants or low-allergen maternal diets in breastfed infants but not for the use of additional fibre or lactase. There were several issues in regards to methodological rigour. Behavioural studies on the use of increased stimulation gave unfavourable results, whereas results from the use of decreased stimulation and contingent music were favourable. These studies demonstrated poor methodological rigour. There is some scientific evidence to support the use of a casein hydrolysate formula in formula-fed infants or a low-allergen maternal diet in breastfed infants with infantile colic. However, there is little scientific evidence to support the use of Simethicone, Dicyclomine hydrochloride, Cimetropium bromide, lactase, additional fibre or behavioural interventions. Further research of good methodological quality on low-allergenic formulas and maternal diets is indicated. © 2011 The Authors. Journal of Paediatrics and Child Health © 2011 Paediatrics and Child Health Division (Royal Australasian College of Physicians).
Bjarnason, I; Batt, R; Catt, S; Macpherson, A; Maxton, D; Menzies, I S
1996-01-01
BACKGROUND/AIM: The reliability of a quantitative method for the non-invasive assessment of intestinal disaccharide hydrolysis was assessed. METHODS: Differential excretion of intact disaccharide, expressed as ratios of lactulose to appropriate hydrolysable disaccharides in urine collected following combined ingestion, has been investigated in healthy volunteers with drug induced alpha-glucosidase inhibition, in subjects with primary hypolactasia, and patients with coeliac disease. RESULTS: Oral administration of the alpha-glucosidase inhibitor 'Acarbose' (BAY g 5421, 200 mg) together with sucrose and lactulose increased the urinary sucrose/lactulose excretion ratios (% dose/10 h) fivefold. The effect was quantitatively reproducible, a higher dose of 'Acarbose' (500 mg) increasing the excretion ratio to about 1.0 indicating complete inhibition of intestinal sucrase activity. The suitability of the method for measuring differences in dose/response and duration of action was assessed by comparing three different alpha-glucosidase inhibitors (BAY g 5421, BAY m 1099, and BAY o 1248) and found to be satisfactory. Subjects with primary adult hypolactasia had urine lactose/lactulose excretion ratios raised to values indicating reduced rather than complete absence of lactase activity whereas sucrose/lactulose ratios were not significantly affected. 'Whole' intestinal disaccharidase activity assessed by this method demonstrated impairment of lactase, sucrase, and isomaltase in eight, one, and seven, respectively, of 20 patients with coeliac disease. By contrast in vitro assay of jejunal biopsy tissue indicated pan-disaccharidase deficiency in all but five of these patients. This shows the importance of distinguishing between 'local' and 'whole' intestinal performance. CONCLUSIONS: Differential urinary excretion of ingested disaccharides provides a reliable, quantitative, and non-invasive technique for assessing profiles of intestinal disaccharidase activity. PMID:8949640
Translational Advances in Pain and Anesthesia for Cancer Patients
2012-01-01
Surgical Research, Fort Sam Houston, TX. Fax: þ210 271 0830. E mail: christopher.maani@us.army.mil Received 10 August 2010; Accepted 18 November 2010 DOI...and response to anesthetics and analgesics have been identified, including COMT (catechol O methyltransferase), MCR1R (melocortin 1 receptor), and...and persistence. Nat Med 2006;12:1269 1277. 42. Zubieta JK, Heitzeg MM, Smith YR, et al.: COMT val158met genotype affects mu opioid neurotransmitter
Liefeldt, Lutz; Plentz, Annelie; Klempa, Boris; Kershaw, Olivia; Endres, Anne-Sophie; Raab, Ulla; Neumayer, Hans-H; Meisel, Helga; Modrow, Susanne
2005-01-01
Organ transplant recipients infected with parvovirus B19 frequently develop persistent viremia associated with chronic anemia and pure red cell aplasia. In this study, a male renal transplant recipient who had been infected with parvovirus B19/genotype 2 after renal transplantation at the age of 34 years is described. The patient was repeatedly treated with high dose intravenous immunoglobulin (IVIG) that resulted in the resolvement of symptoms but not in virus eradication. During an observation period of 33 months after transplantation three phases associated with high parvovirus B19 viremia were observed. Both the first and the second viremic phases were combined with severe anemia. Parvovirus B19 specific IgM-antibodies were initially detected at the beginning of the second phase in continually rising concentrations. Initially eradication of the virus by immunoglobulin therapy was reported after the first viremic phase [Liefeldt et al. (2002): Nephrol Dial Transplant 17:1840-1842]. Retrospectively this statement has to be corrected. It was based on the use of a qualitative PCR assay specific for parvovirus B19 genotype 1 associated with reduced sensitivity for detection of genotype 2. After sequence analysis of the viral DNA and adjustment of a real-time PCR assay (TaqMan) for quantitative detection of all three B19 virus genotypes analysis of consecutive serum samples allowed the demonstration of long lasting phases with reduced viral loads following IVIG-treatment. These results demonstrate that IVIG treatment of parvovirus B19-triggered anemia in transplant recipients offers an opportunity to resolve symptoms, but does not guarantee eradication of the virus. Since reactivation of parvovirus B19 infection can result in high virus load associated with the recurrence of symptoms repeated screening for viral DNA is recommended using the TaqMan system established for quantitative detection of all three genotypes of parvovirus B19. Copyright 2005 Wiley-Liss, Inc.
Tan, Kim-Kee; Zulkifle, Nurul-Izzani; Abd-Jamil, Juraina; Sulaiman, Syuhaida; Yaacob, Che Norainon; Azizan, Noor Syahida; Che Mat Seri, Nurul Asma Anati; Samsudin, Nur Izyan; Mahfodz, Nur Hidayana; AbuBakar, Sazaly
2017-10-01
Dengue is hyperendemic in most of Southeast Asia. In this region, all four dengue virus serotypes are persistently present. Major dengue outbreak cycle occurs in a cyclical pattern involving the different dengue virus serotypes. In Malaysia, since the 1980s, the major outbreak cycles have involved dengue virus type 3 (DENV3), dengue virus type 1 (DENV1) and dengue virus type 2 (DENV2), occurring in that order (DENV3/DENV1/DENV2). Only limited information on the DENV3 cycles, however, have been described. In the current study, we examined the major outbreak cycle involving DENV3 using data from 1985 to 2016. We examined the genetic diversity of DENV3 isolates obtained during the period when DENV3 was the dominant serotype and during the inter-dominant transmission period. Results obtained suggest that the typical DENV3/DENV1/DENV2 cyclical outbreak cycle in Malaysia has recently been disrupted. The last recorded major outbreak cycle involving DENV3 occurred in 2002, and the expected major outbreak cycle involving DENV3 in 2006-2012 did not materialize. DENV genome analyses revealed that DENV3 genotype II (DENV3/II) was the predominant DENV3 genotype (67%-100%) recovered between 1987 and 2002. DENV3 genotype I (DENV3/I) emerged in 2002 followed by the introduction of DENV3 genotype III (DENV3/III) in 2008. These newly emerged DENV3 genotypes replaced DENV3/II, but there was no major upsurge of DENV3 cases that accompanied the emergence of these viruses. DENV3 remained in the background of DENV1 and DENV2 until now. Virus genome sequence analysis suggested that intrinsic differences within the different dengue virus genotypes could have influenced the transmission efficiency of DENV3. Further studies and continuous monitoring of the virus are needed for better understanding of the DENV transmission dynamics in hyperendemic regions. Copyright © 2017 Elsevier B.V. All rights reserved.
Clinical implications of asymptomatic Plasmodium falciparum infections in Malawi.
Buchwald, Andrea G; Sixpence, Alick; Chimenya, Mabvuto; Damson, Milius; Sorkin, John D; Wilson, Mark L; Seydel, Karl; Hochman, Sarah; Mathanga, Don P; Taylor, Terrie E; Laufer, Miriam K
2018-05-16
Asymptomatic Plasmodium falciparum infections are common in Malawi, however, the implications of these infections for the burden of malaria illness are unknown. Whether asymptomatic infections eventually progress to malaria illness, persist without causing symptoms, or clear spontaneously remains undetermined. We identified asymptomatic infections and evaluated the associations between persistent asymptomatic infections and malaria illness. Children and adults (N = 120) who presented at a health facility with uncomplicated malaria were followed monthly for two years. During follow-up visits, participants with malaria symptoms were tested and treated if positive. Samples from all visits were tested for parasites using both microscopy and PCR, and all malaria infections underwent genotyping. Cox frailty models were used to estimate the temporal association between asymptomatic infections and malaria illness episodes. Mixed models were used to estimate the odds of clinical symptoms associated with new versus persistent infections. Participants had a median follow-up time of 720 days. Asymptomatic infections were detected during 23% of visits. Persistent asymptomatic infections were associated with decreased risk of malaria illness in all ages (HR 0.50, p < 0.001). When asymptomatic infections preceded malaria illness, newly acquired infections were detected at 92% of subsequent clinical episodes, independent of presence of persistent infections. Malaria illness among children was more likely due to newly acquired infections (OR 1.4, 95%CI 1.3-1.5) than to persistent infections. Asymptomatic P. falciparum infections are associated with decreased incidence of malaria illness but do not protect against disease when new infection occurs.
Laso-Jadart, Romuald; Harmant, Christine; Quach, Hélène; Zidane, Nora; Tyler-Smith, Chris; Mehdi, Qasim; Ayub, Qasim; Quintana-Murci, Lluis; Patin, Etienne
2017-12-07
From the eighth century onward, the Indian Ocean was the scene of extensive trade of sub-Saharan African slaves via sea routes controlled by Muslim Arab and Swahili traders. Several populations in present-day Pakistan and India are thought to be the descendants of such slaves, yet their history of admixture and natural selection remains largely undefined. Here, we studied the genome-wide diversity of the African-descent Makranis, who reside on the Arabian Sea coast of Pakistan, as well that of four neighboring Pakistani populations, to investigate the genetic legacy, population dynamics, and tempo of the Indian Ocean slave trade. We show that the Makranis are the result of an admixture event between local Baluch tribes and Bantu-speaking populations from eastern or southeastern Africa; we dated this event to ∼300 years ago during the Omani Empire domination. Levels of parental relatedness, measured through runs of homozygosity, were found to be similar across Pakistani populations, suggesting that the Makranis rapidly adopted the traditional practice of endogamous marriages. Finally, we searched for signatures of post-admixture selection at traits evolving under positive selection, including skin color, lactase persistence, and resistance to malaria. We demonstrate that the African-specific Duffy-null blood group-believed to confer resistance against Plasmodium vivax infection-was recently introduced to Pakistan through the slave trade and evolved adaptively in this P. vivax malaria-endemic region. Our study reconstructs the genetic and adaptive history of a neglected episode of the African Diaspora and illustrates the impact of recent admixture on the diffusion of adaptive traits across human populations. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.
Early Back-to-Africa Migration into the Horn of Africa
Hodgson, Jason A.; Mulligan, Connie J.; Al-Meeri, Ali; Raaum, Ryan L.
2014-01-01
Genetic studies have identified substantial non-African admixture in the Horn of Africa (HOA). In the most recent genomic studies, this non-African ancestry has been attributed to admixture with Middle Eastern populations during the last few thousand years. However, mitochondrial and Y chromosome data are suggestive of earlier episodes of admixture. To investigate this further, we generated new genome-wide SNP data for a Yemeni population sample and merged these new data with published genome-wide genetic data from the HOA and a broad selection of surrounding populations. We used multidimensional scaling and ADMIXTURE methods in an exploratory data analysis to develop hypotheses on admixture and population structure in HOA populations. These analyses suggested that there might be distinct, differentiated African and non-African ancestries in the HOA. After partitioning the SNP data into African and non-African origin chromosome segments, we found support for a distinct African (Ethiopic) ancestry and a distinct non-African (Ethio-Somali) ancestry in HOA populations. The African Ethiopic ancestry is tightly restricted to HOA populations and likely represents an autochthonous HOA population. The non-African ancestry in the HOA, which is primarily attributed to a novel Ethio-Somali inferred ancestry component, is significantly differentiated from all neighboring non-African ancestries in North Africa, the Levant, and Arabia. The Ethio-Somali ancestry is found in all admixed HOA ethnic groups, shows little inter-individual variance within these ethnic groups, is estimated to have diverged from all other non-African ancestries by at least 23 ka, and does not carry the unique Arabian lactase persistence allele that arose about 4 ka. Taking into account published mitochondrial, Y chromosome, paleoclimate, and archaeological data, we find that the time of the Ethio-Somali back-to-Africa migration is most likely pre-agricultural. PMID:24921250
Bogema, D. R.; Deutscher, A. T.; Fell, S.; Collins, D.; Eamens, G. J.
2015-01-01
Theileria orientalis is an emerging pathogen of cattle in Asia, Australia, and New Zealand. This organism is a vector-borne hemoprotozoan that causes clinical disease characterized by anemia, abortion, and death, as well as persistent subclinical infections. Molecular methods of diagnosis are preferred due to their sensitivity and utility in differentiating between pathogenic and apathogenic genotypes. Conventional PCR (cPCR) assays for T. orientalis detection and typing are laborious and do not provide an estimate of parasite load. Current real-time PCR assays cannot differentiate between clinically relevant and benign genotypes or are only semiquantitative without a defined clinical threshold. Here, we developed and validated a hydrolysis probe quantitative PCR (qPCR) assay which universally detects and quantifies T. orientalis and identifies the clinically associated Ikeda and Chitose genotypes (UIC assay). Comparison of the UIC assay results with previously validated universal and genotype-specific cPCR results demonstrated that qPCR detects and differentiates T. orientalis with high sensitivity and specificiy. Comparison of quantitative results based on percent parasitemia, determined via blood film analysis and packed cell volume (PCV) revealed significant positive and negative correlations, respectively. One-way analysis of variance (ANOVA) indicated that blood samples from animals with clinical signs of disease contained statistically higher concentrations of T. orientalis DNA than animals with subclinical infections. We propose clinical thresholds to assist in classifying high-, moderate-, and low-level infections and describe how parasite load and the presence of the Ikeda and Chitose genotypes relate to disease. PMID:25588653
Ye, Jing; Cheng, Bei; Cheng, Yi-Fan; Yao, Ye-Li; Xie, Xing; Lu, Wei-Guo; Cheng, Xiao-Dong
Histological low-grade squamous intraepithelial lesion/cervical intraepithelial neoplasia grade 1 (LSIL/CIN1) preceded by normal or mildly abnormal cytology is recommended for conservative follow-up, with no separated management. In this study, we assessed the triage value of human papillomavirus (HPV) 16/18 genotyping in 273 patients with LSIL/CIN1. HPV16/18 genotyping was performed at baseline and follow-up was at 6-monthly intervals for up to 2 years. At each follow-up, women positive for cytology or high-risk HPV (hrHPV) were referred for colposcopy. Enrollment cytology, HPV16/18 genotyping, and questionnaire-obtained factors were linked to the 2-year cumulative progression rate. Univariate and multivariate analyses were performed taking into account time-to-event with Cox proportional hazard regression. The results showed that 190 cases (69.6%) regressed, 37 (13.6%) persisted, and 46 (16.8%) progressed. HPV16/18 positivity (hazard ratio (HR), 2.708; 95% confidence interval (CI), 1.432-5.121; P=0.002) is significantly associated with higher 2-year cumulative progression rate. Sub-analysis by enrollment cytology and age restricted the positive association among patients preceded by mildly abnormal cytology and aged 30 years or older. Immediate treatment is a rational recommendation for the high-risk subgroup, when good compliance is not assured.
Abdolrasouli, Alireza; Bercusson, Amelia C; Rhodes, Johanna L; Hagen, Ferry; Buil, Jochem B; Tang, Alison Y Y; de Boer, Leonard L; Shah, Anand; Milburn, Andrew J; Elborn, J Stuart; Jones, Andrew L; Meis, Jacques F; Fisher, Matthew C; Schelenz, Silke; Simmonds, Nicholas J; Armstrong-James, Darius
2018-04-27
Infections caused by Rasamsonia argillacea complex have been reported in various clinical settings. Cystic fibrosis (CF) is one of the main underlying conditions. An observational cohort study of CF patients with Rasamsonia in respiratory samples was conducted. Eight isolates from six patients were identified as R. argillacea complex and tested for antifungal susceptibility. All isolates had high MICs to voriconazole and posaconazole and low MECs to echinocandins. Four patients experienced lung function decline in the year preceding first Rasamsonia isolation. This continued in the year following first isolation in three out of four cases. Antifungal therapy was initiated in two patients, to which only one exhibited a clinical response. Three out of six patients died within three years of isolating Rasamsonia. Genotyping suggests that similar genotypes of Rasamsonia can persist in CF airways. Consistent with other fungi in CF, the clinical impact of airway colonization by Rasamsonia is variable. In certain patients, Rasamsonia may be able to drive clinical decline. In others, though a clear impact on lung function may be difficult to determine, the appearance of Rasamsonia acts as a marker of disease severity. In others it does not appear to have an obvious clinical impact on disease progression. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Shurtliff, Quinn R; Murphy, Peter J; Matocq, Marjorie D
2014-03-01
The degree to which closely related species interbreed is determined by a complex interaction of ecological, behavioral, and genetic factors. We examine the degree of interbreeding between two woodrat species, Neotoma bryanti and N. lepida, at a sharp ecological transition. We identify the ecological association of each genotypic class, assess the opportunity for mating between these groups, and test whether they have similar patterns of year-to-year persistence on our study site. We find that 13% of individuals have a hybrid signature but that the two parental populations and backcrosses are highly segregated by habitat type and use. Also, we find that adult hybrids are comparable to parental types in terms of year-to-year persistence on our site but that, among juveniles, significantly fewer hybrids reach adulthood on site compared to their purebred counterparts. Our analyses show that this hybrid zone is maintained by occasional nonassortative mating coupled with hybrid fertility, but that these factors are balanced by lower apparent survival of juvenile hybrids and habitat-based preference or selection that limits heterospecific mating while promoting backcrossing to habitat-specific genotypes. This system presents a novel example of the role that sharp resource gradients play in reproductive isolation and the potential for genetic introgression. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.
Molecular Investigation of Tularemia Outbreaks, Spain, 1997–2008
Ariza-Miguel, Jaime; Johansson, Anders; Fernández-Natal, María Isabel; Martínez-Nistal, Carmen; Orduña, Antonio; Rodríguez-Ferri, Elías F.; Hernández, Marta
2014-01-01
Tularemia outbreaks occurred in northwestern Spain in 1997–1998 and 2007–2008 and affected >1,000 persons. We assessed isolates involved in these outbreaks by using pulsed-field gel electrophoresis with 2 restriction enzymes and multilocus variable number tandem repeat analysis of 16 genomic loci of Francisella tularensis, the cause of this disease. Isolates were divided into 3 pulsotypes by pulsed-field gel electrophoresis and 8 allelic profiles by multilocus variable number tandem repeat analysis. Isolates obtained from the second tularemia outbreak had the same genotypes as isolates obtained from the first outbreak. Both outbreaks were caused by genotypes of genetic subclade B.Br:FTNF002–00, which is widely distributed in countries in central and western Europe. Thus, reemergence of tularemia in Spain was not caused by the reintroduction of exotic strains, but probably by persistence of local reservoirs of infection. PMID:24750848
Pneumonic Plague Outbreak, Northern Madagascar, 2011
Richard, Vincent; Herindrainy, Perlinot; Soanandrasana, Rahelinirina; Ratsitoharina, Maherisoa; Rakotomanana, Fanjasoa; Andrianalimanana, Samuel; Scholz, Holger C.; Rajerison, Minoarisoa
2015-01-01
Yersinia pestis, the causative agent of plague, is endemic to Madagascar, particularly to the central highlands. Although plague has not been previously reported in northern Madagascar, an outbreak of pneumonic plague occurred in this remote area in 2011. Over a 27-day period, 17 suspected, 2 presumptive, and 3 confirmed human cases were identified, and all 15 untreated 20 patients died. Molecular typing of Y. pestis isolated from 2 survivors and 5 Rattus rattus rat samples identified the Madagascar-specific 1.ORI3-k single-nucleotide polymorphism genotype and 4 clustered regularly interspaced short palindromic repeat patterns. This outbreak had a case-fatality rate of 100% for nontreated patients. The Y. pestis 1.ORI3-k single-nucleotide polymorphism genotype might cause larger epidemics. Multidrug-resistant strains and persistence of the pathogen in natural foci near human settlements pose severe risks to populations in plague-endemic regions and require outbreak response strategies. PMID:25530466
Urinary tract infection in iNOS-deficient mice with focus on bacterial sensitivity to nitric oxide.
Poljakovic, Mirjana; Persson, Katarina
2003-01-01
Inducible nitric oxide synthase (iNOS)-deficient mice were used to examine the role of iNOS in Escherichia coli-induced urinary tract infection (UTI). The toxicity of nitric oxide (NO)/peroxynitrite to bacteria and host was also investigated. The nitrite levels in urine of iNOS+/+ but not iNOS/ mice increased after infection. No differences in bacterial clearance or persistence were noted between the genotypes. In vitro, the uropathogenic E. coli 1177 was sensitive to 3-morpholinosydnonimine, whereas the avirulent E. coli HB101 was sensitive to both NO and 3-morpholinosydnonimine. E. coli HB101 was statistically (P < 0.05) more sensitive to peroxynitrite than E. coli 1177. Nitrotyrosine immunoreactivity was observed in infected bladders of both genotypes and in infected kidneys of iNOS+/+ mice. Myeloperoxidase, neuronal (n)NOS, and endothelial (e)NOS immunoreactivity was observed in inflammatory cells of both genotypes. Our results indicate that iNOS/ and iNOS+/+ mice are equally susceptible to E. coli-induced UTI and that the toxicity of NO to E. coli depends on bacterial virulence. Furthermore, myeloperoxidase and nNOS/eNOS may contribute to nitrotyrosine formation in the absence of iNOS.
Development of Polymorphic Microsatellite Loci for Potato Wart from Next-Generation Sequence Data.
Gagnon, Marie-Claude; van der Lee, Theo A J; Bonants, Peter J M; Smith, Donna S; Li, Xiang; Lévesque, C André; Bilodeau, Guillaume J
2016-06-01
Synchytrium endobioticum is the fungal agent causing potato wart disease. Because of its severity and persistence, quarantine measures are enforced worldwide to avoid the spread of this disease. Molecular markers exist for species-specific detection of this pathogen, yet markers to study the intraspecific genetic diversity of S. endobioticum were not available. Whole-genome sequence data from Dutch pathotype 1 isolate MB42 of S. endobioticum were mined for perfect microsatellite motifs. Of the 62 selected microsatellites, 21 could be amplified successfully and displayed moderate levels of polymorphism in 22 S. endobioticum isolates from different countries. Nineteen multilocus genotypes were observed, with only three isolates from Canada displaying identical profiles. The majority of isolates from Canada clustered genetically. In contrast, most isolates collected in Europe show no genetic clustering associated with their geographic origin. S. endobioticum isolates with the same pathotype displayed highly variable genotypes and none of the microsatellite markers correlated with a specific pathotype. The markers developed in this study can be used to assess intraspecific genetic diversity of S. endobioticum and allow track and trace of genotypes that will generate a better understanding of the migration and spread of this important fungal pathogen and support management of this disease.
Co-evolution of Mycobacterium tuberculosis and Homo sapiens
Brites, Daniela; Gagneux, Sebastien
2015-01-01
The causative agent of human tuberculosis (TB), Mycobacterium tuberculosis, is an obligate pathogen that evolved to exclusively persist in human populations. For M. tuberculosis to transmit from person to person, it has to cause pulmonary disease. Therefore, M. tuberculosis virulence has likely been a significant determinant of the association between M. tuberculosis and humans. Indeed, the evolutionary success of some M. tuberculosis genotypes seems at least partially attributable to their increased virulence. The latter possibly evolved as a consequence of human demographic expansions. If co-evolution occurred, humans would have counteracted to minimize the deleterious effects of M. tuberculosis virulence. The fact that human resistance to infection has a strong genetic basis is a likely consequence of such a counter-response. The genetic architecture underlying human resistance to M. tuberculosis remains largely elusive. However, interactions between human genetic polymorphisms and M. tuberculosis genotypes have been reported. Such interactions are consistent with local adaptation and allow for a better understanding of protective immunity in TB. Future ‘genome-to-genome’ studies, in which locally associated human and M. tuberculosis genotypes are interrogated in conjunction, will help identify new protective antigens for the development of better TB vaccines. PMID:25703549
Social complementation and growth advantages promote socially defective bacterial isolates.
Kraemer, Susanne A; Velicer, Gregory J
2014-04-22
Social interactions among diverse individuals that encounter one another in nature have often been studied among animals but rarely among microbes. For example, the evolutionary forces that determine natural frequencies of bacteria that express cooperative behaviours at low levels remain poorly understood. Natural isolates of the soil bacterium Myxococcus xanthus sampled from the same fruiting body often vary in social phenotypes, such as group swarming and multicellular development. Here, we tested whether genotypes highly proficient at swarming or development might promote the persistence of less socially proficient genotypes from the same fruiting body. Fast-swarming strains complemented slower isolates, allowing the latter to keep pace with faster strains in mixed groups. During development, one low-sporulating strain was antagonized by high sporulators, whereas others with severe developmental defects had those defects partially complemented by high-sporulating strains. Despite declining in frequency overall during competition experiments spanning multiple cycles of development, developmentally defective strains exhibited advantages during the growth phases of competitions. These results suggest that microbes with low-sociality phenotypes often benefit from interacting with more socially proficient strains. Such complementation may combine with advantages at other traits to increase equilibrium frequencies of low-sociality genotypes in natural populations.
Coral reef fish populations can persist without immigration
Salles, Océane C.; Maynard, Jeffrey A.; Joannides, Marc; Barbu, Corentin M.; Saenz-Agudelo, Pablo; Almany, Glenn R.; Berumen, Michael L.; Thorrold, Simon R.; Jones, Geoffrey P.; Planes, Serge
2015-01-01
Determining the conditions under which populations may persist requires accurate estimates of demographic parameters, including immigration, local reproductive success, and mortality rates. In marine populations, empirical estimates of these parameters are rare, due at least in part to the pelagic dispersal stage common to most marine organisms. Here, we evaluate population persistence and turnover for a population of orange clownfish, Amphiprion percula, at Kimbe Island in Papua New Guinea. All fish in the population were sampled and genotyped on five occasions at 2-year intervals spanning eight years. The genetic data enabled estimates of reproductive success retained in the same population (reproductive success to self-recruitment), reproductive success exported to other subpopulations (reproductive success to local connectivity), and immigration and mortality rates of sub-adults and adults. Approximately 50% of the recruits were assigned to parents from the Kimbe Island population and this was stable through the sampling period. Stability in the proportion of local and immigrant settlers is likely due to: low annual mortality rates and stable egg production rates, and the short larval stages and sensory capacities of reef fish larvae. Biannual mortality rates ranged from 0.09 to 0.55 and varied significantly spatially. We used these data to parametrize a model that estimated the probability of the Kimbe Island population persisting in the absence of immigration. The Kimbe Island population was found to persist without significant immigration. Model results suggest the island population persists because the largest of the subpopulations are maintained due to having low mortality and high self-recruitment rates. Our results enable managers to appropriately target and scale actions to maximize persistence likelihood as disturbance frequencies increase. PMID:26582017
Coral reef fish populations can persist without immigration.
Salles, Océane C; Maynard, Jeffrey A; Joannides, Marc; Barbu, Corentin M; Saenz-Agudelo, Pablo; Almany, Glenn R; Berumen, Michael L; Thorrold, Simon R; Jones, Geoffrey P; Planes, Serge
2015-11-22
Determining the conditions under which populations may persist requires accurate estimates of demographic parameters, including immigration, local reproductive success, and mortality rates. In marine populations, empirical estimates of these parameters are rare, due at least in part to the pelagic dispersal stage common to most marine organisms. Here, we evaluate population persistence and turnover for a population of orange clownfish, Amphiprion percula, at Kimbe Island in Papua New Guinea. All fish in the population were sampled and genotyped on five occasions at 2-year intervals spanning eight years. The genetic data enabled estimates of reproductive success retained in the same population (reproductive success to self-recruitment), reproductive success exported to other subpopulations (reproductive success to local connectivity), and immigration and mortality rates of sub-adults and adults. Approximately 50% of the recruits were assigned to parents from the Kimbe Island population and this was stable through the sampling period. Stability in the proportion of local and immigrant settlers is likely due to: low annual mortality rates and stable egg production rates, and the short larval stages and sensory capacities of reef fish larvae. Biannual mortality rates ranged from 0.09 to 0.55 and varied significantly spatially. We used these data to parametrize a model that estimated the probability of the Kimbe Island population persisting in the absence of immigration. The Kimbe Island population was found to persist without significant immigration. Model results suggest the island population persists because the largest of the subpopulations are maintained due to having low mortality and high self-recruitment rates. Our results enable managers to appropriately target and scale actions to maximize persistence likelihood as disturbance frequencies increase. © 2015 The Author(s).
Persistence of highly pathogenic avian influenza H5N1 virus defined by agro-ecological niche
Hogerwerf, Lenny; Wallace, Rob G.; Ottaviani, Daniela; Slingenbergh, Jan; Prosser, Diann; Bergmann, Luc; Gilbert, Marius
2010-01-01
The highly pathogenic avian influenza (HPAI) H5N1 virus has spread across Eurasia and into Africa. Its persistence in a number of countries continues to disrupt poultry production, impairs smallholder livelihoods, and raises the risk a genotype adapted to human-to-human transmission may emerge. While previous studies identified domestic duck reservoirs as a primary risk factor associated with HPAI H5N1 persistence in poultry in Southeast Asia, little is known of such factors in countries with different agro-ecological conditions, and no study has investigated the impact of such conditions on HPAI H5N1 epidemiology at the global scale. This study explores the patterns of HPAI H5N1 persistence worldwide, and for China, Indonesia, and India includes individual provinces that have reported HPAI H5N1 presence during the 2004–2008 period. Multivariate analysis of a set of 14 agricultural, environmental, climatic, and socio-economic factors demonstrates in quantitative terms that a combination of six variables discriminates the areas with human cases and persistence: agricultural population density, duck density, duck by chicken density, chicken density, the product of agricultural population density and chicken output/input ratio, and purchasing power per capita. The analysis identifies five agro-ecological clusters, or niches, representing varying degrees of disease persistence. The agro-ecological distances of all study areas to the medoid of the niche with the greatest number of human cases are used to map HPAI H5N1 risk globally. The results indicate that few countries remain where HPAI H5N1 would likely persist should it be introduced.
Gianella, Sara; Vazquez, Homero; Ignacio, Caroline; Zweig, Adam C.; Richman, Douglas D.; Smith, Davey M.
2014-01-01
Abstract We investigated the pol genotype in two phylogenetically and epidemiologically linked partners, who were both experiencing persistent low-level viremia during antiretroviral therapy. In one partner we identified a new residue insertion between codon 248 and 249 of the HIV-1 RNA reverse transcriptase (RT) coding region (HXB2 numbering). We then investigated the potential impact of identified mutations in RT and antiretroviral binding affinity using a novel computational approach. PMID:24020934
Winkler, Ethan A.; Yue, John K.; Ferguson, Adam R.; Temkin, Nancy R.; Stein, Murray B.; Barber, Jason; Yuh, Esther L.; Sharma, Sourabh; Satris, Gabriela G.; McAllister, Thomas W.; Rosand, Jonathan; Sorani, Marco D.; Lingsma, Hester F.; Tarapore, Phiroz E.; Burchard, Esteban G.; Hu, Donglei; Eng, Celeste; Wang, Kevin K.W.; Mukherjee, Pratik; Okonkwo, David O.; Diaz-Arrastia, Ramon; Manley, Geoffrey T.
2017-01-01
Mild traumatic brain injury (mTBI) results in variable clinical trajectories and outcomes. The source of variability remains unclear, but may involve genetic variations, such as single nucleotide polymorphisms (SNPs). A SNP in catechol-o-methyltransferase (COMT) is suggested to influence development of post-traumatic stress disorder (PTSD), but its role in TBI remains unclear. Here, we utilize the Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot (TRACK-TBI Pilot) study to investigate whether the COMT Val158Met polymorphism is associated with PTSD and global functional outcome as measured by the PTSD Checklist – Civilian Version and Glasgow Outcome Scale Extended (GOSE), respectively. Results in 93 predominately Caucasian subjects with mTBI show that the COMT Met158 allele is associated with lower incidence of PTSD (univariate odds ratio (OR) of 0.25, 95% CI [0.09–0.69]) and higher GOSE scores (univariate OR 2.87, 95% CI [1.20–6.86]) 6-months following injury. The COMT Val158Met genotype and PTSD association persists after controlling for race (multivariable OR of 0.29, 95% CI [0.10–0.83]) and pre-existing psychiatric disorders/substance abuse (multivariable OR of 0.32, 95% CI [0.11–0.97]). PTSD emerged as a strong predictor of poorer outcome on GOSE (multivariable OR 0.09, 95% CI [0.03–0.26]), which persists after controlling for age, GCS, and race. When accounting for PTSD in multivariable analysis, the association of COMT genotype and GOSE did not remain significant (multivariable OR 1.73, 95% CI [0.69–4.35]). Whether COMT genotype indirectly influences global functional outcome through PTSD remains to be determined and larger studies in more diverse populations are needed to confirm these findings. PMID:27769642
Winkler, Ethan A; Yue, John K; Ferguson, Adam R; Temkin, Nancy R; Stein, Murray B; Barber, Jason; Yuh, Esther L; Sharma, Sourabh; Satris, Gabriela G; McAllister, Thomas W; Rosand, Jonathan; Sorani, Marco D; Lingsma, Hester F; Tarapore, Phiroz E; Burchard, Esteban G; Hu, Donglei; Eng, Celeste; Wang, Kevin K W; Mukherjee, Pratik; Okonkwo, David O; Diaz-Arrastia, Ramon; Manley, Geoffrey T
2017-01-01
Mild traumatic brain injury (mTBI) results in variable clinical trajectories and outcomes. The source of variability remains unclear, but may involve genetic variations, such as single nucleotide polymorphisms (SNPs). A SNP in catechol-o-methyltransferase (COMT) is suggested to influence development of post-traumatic stress disorder (PTSD), but its role in TBI remains unclear. Here, we utilize the Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot (TRACK-TBI Pilot) study to investigate whether the COMT Val 158 Met polymorphism is associated with PTSD and global functional outcome as measured by the PTSD Checklist - Civilian Version and Glasgow Outcome Scale Extended (GOSE), respectively. Results in 93 predominately Caucasian subjects with mTBI show that the COMT Met 158 allele is associated with lower incidence of PTSD (univariate odds ratio (OR) of 0.25, 95% CI [0.09-0.69]) and higher GOSE scores (univariate OR 2.87, 95% CI [1.20-6.86]) 6-months following injury. The COMT Val 158 Met genotype and PTSD association persists after controlling for race (multivariable OR of 0.29, 95% CI [0.10-0.83]) and pre-existing psychiatric disorders/substance abuse (multivariable OR of 0.32, 95% CI [0.11-0.97]). PTSD emerged as a strong predictor of poorer outcome on GOSE (multivariable OR 0.09, 95% CI [0.03-0.26]), which persists after controlling for age, GCS, and race. When accounting for PTSD in multivariable analysis, the association of COMT genotype and GOSE did not remain significant (multivariable OR 1.73, 95% CI [0.69-4.35]). Whether COMT genotype indirectly influences global functional outcome through PTSD remains to be determined and larger studies in more diverse populations are needed to confirm these findings. Copyright © 2016 Elsevier Ltd. All rights reserved.
Makkouk, Khaled M; Kumari, Safaa G
2009-05-01
Cool-season food legumes (faba bean, lentil, chickpea and pea) and cereals (bread and durum wheat and barley) are the most important and widely cultivated crops in West Asia and North Africa (WANA), where they are the main source of carbohydrates and protein for the majority of the population. Persistently transmitted aphid-borne viruses pose a significant limitation to legume and cereal production worldwide. Surveys conducted in many countries in WANA during the last three decades established that the most important of these viruses are: Faba bean necrotic yellows virus (FBNYV: genus Nanovirus; family Nanoviridae), Bean leafroll virus (BLRV: genus Luteovirus; family Luteoviridae), Beet western yellows virus (BWYV: genus Polerovirus; family Luteoviridae), Soybean dwarf virus (SbDV: genus Luteovirus; family Luteoviridae) and Chickpea chlorotic stunt virus (CpCSV: genus Polerovirus; family Luteoviridae) which affect legume crops, and Barley yellow dwarf virus-PAV (BYDV-PAV: genus Luteovirus; family Luteoviridae), Barley yellow dwarf virus-MAV (BYDV-MAV: genus Luteovirus; family Luteoviridae) and Cereal yellow dwarf virus-RPV (CYDV-RPV: genus Polerovirus; family Luteoviridae) which affect cereal crops. Loss in yield caused by these viruses is usually high when infection occurs early in the growing season. Many aphid vector species for the above-mentioned viruses are reported to be prevalent in the WANA region. In addition, in this region many wild species (annual or perennial) were found infected with these viruses and may play an important role in their ecology and spread. Fast spread of these diseases was always associated with high aphid vector populations and activity. Although virus disease management can be achieved by combining several control measures, development of resistant genotypes is undoubtedly one of the most appropriate control methods. Over the last three decades barley and wheat genotypes resistant to BYDV, faba bean genotypes resistant to BLRV, and lentil genotypes resistant to BLRV, FBNYV and SbDV have been successfully identified. Moreover, progress has been made in disease management of some of these viruses using a combination of management options. Experience gathered over the last few decades clearly showed that no single method of virus disease control suffices to reduce yield losses in legume and cereal crops.
Genetic polymorphisms in CYP1A1, CYP1B1 and COMT genes in Greenlandic Inuit and Europeans.
Ghisari, Mandana; Long, Manhai; Bonefeld-Jørgensen, Eva C
2013-01-01
The Indigenous Arctic population is of Asian descent, and their genetic background is different from the Caucasian populations. Relatively little is known about the specific genetic polymorphisms in genes involved in the activation and detoxification mechanisms of environmental contaminants in Inuit and its relation to health risk. The Greenlandic Inuit are highly exposed to legacy persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), and an elucidation of gene-environment interactions in relation to health risks is needed. The aim of this study was to determine and compare the genotype and allele frequencies of the cytochrome P450 CYP1A1 Ile462Val (rs1048943), CYP1B1 Leu432Val (rs1056836) and catechol-O-methyltransferase COMT Val158Met (rs4680) in Greenlandic Inuit (n=254) and Europeans (n=262) and explore the possible relation between the genotypes and serum levels of POPs. The genotype and allele frequency distributions of the three genetic polymorphisms differed significantly between the Inuit and Europeans. For Inuit, the genotype distribution was more similar to those reported for Asian populations. We observed a significant difference in serum polychlorinated biphenyl (CB-153) and the pesticide 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE) levels between Inuit and Europeans, and for Inuit also associations between the POP levels and genotypes for CYP1A1, CYP1B1 and COMT. Our data provide new information on gene polymorphisms in Greenlandic Inuit that might support evaluation of susceptibility to environmental contaminants and warrant further studies.
Genetic polymorphisms in CYP1A1, CYP1B1 and COMT genes in Greenlandic Inuit and Europeans
Ghisari, Mandana; Long, Manhai; Bonefeld-Jørgensen, Eva C.
2013-01-01
Background The Indigenous Arctic population is of Asian descent, and their genetic background is different from the Caucasian populations. Relatively little is known about the specific genetic polymorphisms in genes involved in the activation and detoxification mechanisms of environmental contaminants in Inuit and its relation to health risk. The Greenlandic Inuit are highly exposed to legacy persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), and an elucidation of gene–environment interactions in relation to health risks is needed. Objectives The aim of this study was to determine and compare the genotype and allele frequencies of the cytochrome P450 CYP1A1 Ile462Val (rs1048943), CYP1B1 Leu432Val (rs1056836) and catechol-O-methyltransferase COMT Val158Met (rs4680) in Greenlandic Inuit (n=254) and Europeans (n=262) and explore the possible relation between the genotypes and serum levels of POPs. Results The genotype and allele frequency distributions of the three genetic polymorphisms differed significantly between the Inuit and Europeans. For Inuit, the genotype distribution was more similar to those reported for Asian populations. We observed a significant difference in serum polychlorinated biphenyl (CB-153) and the pesticide 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p′-DDE) levels between Inuit and Europeans, and for Inuit also associations between the POP levels and genotypes for CYP1A1, CYP1B1 and COMT. Conclusion Our data provide new information on gene polymorphisms in Greenlandic Inuit that might support evaluation of susceptibility to environmental contaminants and warrant further studies. PMID:23785672
Stanton, Jeffrey J; Zong, Jian-Chao; Eng, Crystal; Howard, Lauren; Flanagan, Joe; Stevens, Martina; Schmitt, Dennis; Wiedner, Ellen; Graham, Danielle; Junge, Randall E; Weber, Martha A; Fischer, Martha; Mejia, Alicia; Tan, Jie; Latimer, Erin; Herron, Alan; Hayward, Gary S; Ling, Paul D
2013-03-01
Elephant endotheliotropic herpesviruses (EEHVs) can cause fatal hemorrhagic disease in juvenile Asian elephants (Elphas maximus); however, sporadic shedding of virus in trunk washes collected from healthy elephants also has been detected. Data regarding the relationship of viral loads in blood compared with trunk washes are lacking, and questions about whether elephants can undergo multiple infections with EEHVs have not been addressed previously. Real-time quantitative polymerase chain reaction was used to determine the kinetics of EEHV1 loads, and genotypic analysis was performed on EEHV1 DNA detected in various fluid samples obtained from five Asian elephants that survived detectable EEHV1 DNAemia on at least two separate occasions. In three elephants displaying clinical signs of illness, preclinical EEHV1 DNAemia was detectable, and peak whole-blood viral loads occurred 3-8 days after the onset of clinical signs. In two elephants with EEHV1 DNAemia that persisted for 7-21 days, no clinical signs of illness were observed. Detection of EEHV1 DNA in trunk washes peaked approximately 21 days after DNAemia, and viral genotypes detected during DNAemia matched those detected in subsequent trunk washes from the same elephant. In each of the five elephants, two distinct EEHV1 genotypes were identified in whole blood and trunk washes at different time points. In each case, these genotypes represented both an EEHV1A and an EEHV1B subtype. These data suggest that knowledge of viral loads could be useful for the management of elephants before or during clinical illness. Furthermore, sequential infection with both EEHV1 subtypes occurs in Asian elephants, suggesting that they do not elicit cross-protective sterilizing immunity. These data will be useful to individuals involved in the husbandry and clinical care of Asian elephants.
Chatzistamatiou, Kimon; Moysiadis, Theodoros; Angelis, Eleftherios; Kaufmann, Andreas; Skenderi, Alkmini; Jansen-Duerr, Pidder; Lekka, Irini; Kilintzis, Vasilis; Angelidou, Stamatia; Katsiki, Evangelia; Hagemann, Ingke; Tsertanidou, Athena; Koch, Isabel; Boecher, Oliver; Soutschek, Erwin; Maglaveras, Nikolaos; Agorastos, Theodoros
2017-05-01
The purpose of the presented PIPAVIR (persistent infections with human papillomaviruses; http://www.pipavir.com ) subanalysis is to assess the performance of high-risk (hr) HPV-DNA genotyping as a method of primary cervical cancer screening and triage of HPV positive women to colposcopy compared to liquid-based cytology (LBC) in an urban female population. Women, aged 30-60, provided cervicovaginal samples at the Family-Planning Centre, Hippokratio Hospital of Thessaloniki, Greece, and the Department of Gynecology and Obstetrics in Mare Klinikum, Kiel, Germany. Cytology and HPV genotyping was performed using LBC and HPV Multiplex Genotyping (MPG), respectively. Women positive for cytology [atypical squamous cells of undetermined significance (ASC-US) or worse] or hrHPV were referred for colposcopy. Among 1723/1762 women included in the final analysis, hrHPV and HPV16/18 prevalence was 17.7 and 9.6%, respectively. Cytology was ASCUS or worse in 7.6%. Cervical Intraepithelial Neoplasia grade 2 or worse (CIN2+) was detected in 28 women (1.6%). Sensitivity of cytology (ASCUS or worse) and HPV DNA testing for the detection of CIN2+ was 50.0 and 100%, and specificity was 94.49 and 85.49%, respectively. The screening approach according to which only women positive for HPV16/18 and for hrHPV(non16/18) with ASCUS or worse were referred to colposcopy presented 78.57% sensitivity and 13.17% positive predictive value (PPV). HPV testing represents a more sensitive methodology for primary cervical cancer screening compared to cytology. For triage of HPV positive women to colposcopy, partial HPV genotyping offers better sensitivity than cytology, at the cost of higher number of colposcopies.
Lee, Eun-Kyoung; Kang, Hyun-Mi; Kim, Kwang-Il; Choi, Jun-Gu; To, Thanh Long; Nguyen, Tho Dang; Song, Byung-Min; Jeong, Jipseol; Choi, Kang-Seuk; Kim, Ji-Ye; Lee, Hee-Soo; Lee, Youn-Jeong; Kim, Jae-Hong
2015-04-01
In spite of highly pathogenic avian influenza H5N1 vaccination campaigns for domestic poultry, H5N1 viruses continue to circulate in Vietnam. To estimate the prevalence of avian influenza virus in Vietnam, surveillance was conducted between November 2011 and February 2013. Genetic analysis of 312 highly pathogenic avian influenza H5 viruses isolated from poultry in Vietnam was conducted and possible genetic relationships with strains from neighboring countries were investigated. As previously reported, phylogenetic analysis of the avian influenza virus revealed two H5N1 HPAI clades that were circulating in Vietnam. Clade 1.1, related to Cambodian strains, was predominant in the southern provinces, while clade 2.3.2.1 viruses were predominant in the northern and central provinces. Sequence analysis revealed evidence of active genetic evolution. In the gene constellation of clade 2.3.2.1, genotypes A, B, and B(II) existed during the 2011/2012 winter season. In June 2012, new genotype C emerged by reassortment between genotype A and genotype B(II), and this genotype was predominant in 2013 in the northern and central provinces. Interestingly, enzootic Vietnamese clade 2.3.2.1C H5 virus subsequently reassorted with N2, which originated from wild birds, to generate H5N2 highly pathogenic avian influenza, which was isolated from duck in the northeast region. This investigation indicated that H5N1 outbreaks persist in Vietnam and cause genetic reassortment with circulating viruses. It is necessary to strengthen active influenza surveillance to eradicate highly pathogenic avian influenza viruses and sever the link between highly pathogenic avian influenza and other circulating influenza viruses. © 2015 Poultry Science Association Inc.
Reteng, Patrick; Vrisca, Visia; Sukarno, Inka; Djarkoni, Ilham Habib; Kalangi, Jane Angela; Jacobs, George Eduardo; Runtuwene, Lucky Ronald; Eshita, Yuki; Maeda, Ryuichiro; Suzuki, Yutaka; Mongan, Arthur Elia; Warouw, Sarah Maria; Yamagishi, Junya; Tuda, Josef
2017-04-04
Malaria still poses one of the major threats to human health. Development of effective antimalarial drugs has decreased this threat; however, the emergence of drug-resistant Plasmodium falciparum, a cause of Malaria, is disconcerting. The antimalarial drug chloroquine has been effectively used, but resistant parasites have spread worldwide. Interestingly, the withdrawal of the drug reportedly leads to an increased population of susceptible parasites in some cases. We examined the prevalence of genomic polymorphisms in a malaria parasite P. falciparum, associated with resistance to an antimalarial drug chloroquine, after the withdrawal of the drug from Indonesia. Blood samples were collected from 95 malaria patients in North Sulawesi, Indonesia, in 2010. Parasite DNA was extracted and analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for pfcrt and pfmdr1. In parallel, multiplex amplicon sequencing for the same genes was carried out with Illumina MiSeq. Of the 59 cases diagnosed as P. falciparum infection by microscopy, PCR-RFLP analysis clearly identified the genotype 76T in pfcrt in 44 cases. Sequencing analysis validated the identified genotypes in the 44 cases and demonstrated that the haplotype in the surrounding genomic region was exclusively SVMNT. Results of pfmdr1 were successfully obtained for 51 samples, where the genotyping results obtained by the two methods were completely consistent. In pfmdr1, the 86Y mutant genotype was observed in 45 cases (88.2%). Our results suggest that the prevalence of the mutated genotypes remained dominant even 6 years after the withdrawal of chloroquine from this region. Diversified haplotype of the resistance-related locus, potentially involved in fitness costs, unauthorized usage of chloroquine, and/or a short post-withdrawal period may account for the observed high persistence of prevalence.
McCarthy, Maureen S; Lester, Jack D; Howe, Eric J; Arandjelovic, Mimi; Stanford, Craig B; Vigilant, Linda
2015-08-25
As habitat degradation and fragmentation continue to impact wildlife populations around the world, it is critical to understand the behavioral flexibility of species in these environments. In Uganda, the mostly unprotected forest fragment landscape between the Budongo and Bugoma Forests is a potential corridor for chimpanzees, yet little is known about the status of chimpanzee populations in these fragments. From 2011 through 2013, we noninvasively collected 865 chimpanzee fecal samples across 633 km(2) and successfully genotyped 662 (77%) at up to 14 microsatellite loci. These genotypes corresponded to 182 chimpanzees, with a mean of 3.5 captures per individual. We obtained population size estimates of 256 (95% confidence interval 246-321) and 319 (288-357) chimpanzees using capture-with-replacement and spatially explicit capture-recapture models, respectively. The spatial clustering of associated genotypes suggests the presence of at least nine communities containing a minimum of 8-33 individuals each. Putative community distributions defined by the locations of associated genotypes correspond well with the distribution of 14 Y-chromosome haplotypes. These census figures are more than three times greater than a previous estimate based on an extrapolation from small-scale nest count surveys that tend to underestimate population size. The distribution of genotype clusters and Y-chromosome haplotypes together indicate the presence of numerous male philopatric chimpanzee communities throughout the corridor habitat. Our findings demonstrate that, despite extensive habitat loss and fragmentation, chimpanzees remain widely distributed and exhibit distinct community home ranges. Our results further imply that elusive and rare species may adapt to degraded habitats more successfully than previously believed. Their long-term persistence is unlikely, however, if protection is not afforded to them and habitat loss continues unabated.
Circulating Cell-free DNA for Metastatic Cervical Cancer Detection, Genotyping, and Monitoring.
Kang, Zhigang; Stevanović, Sanja; Hinrichs, Christian S; Cao, Liang
2017-11-15
Purpose: Circulating cell-free (ccf) human papillomavirus (HPV) DNA may serve as a unique tumor marker for HPV-associated malignancies, including cervical cancer. We developed a method to genotype and quantify circulating HPV DNA in patients with HPV16- or HPV18-positive metastatic cervical cancer for potential disease monitoring and treatment-related decision making. Experimental Design: In this retrospective study, HPV ccfDNA was measured in serum samples from 19 metastatic cervical cancer patients by duplex digital droplet PCR (ddPCR). Nine patients had received tumor-infiltrating lymphocyte (TIL) immunotherapy. ccfDNA data were aligned with the tumor HPV genotype, drug treatment, and clinical outcome. Results: In blinded tests, HPV ccfDNA was detected in 19 of 19 (100%) patients with HPV-positive metastatic cervical cancer but not in any of the 45 healthy blood donors. The HPV genotype harbored in the patients' tumors was correctly identified in 87 of 87 (100%) sequential patient serum samples from 9 patients who received TIL immunotherapy. In three patients who experienced objective cancer regression after TIL treatment, a transient HPV ccfDNA peak was detected 2-3 days after TIL infusion. Furthermore, persistent clearance of HPV ccfDNA was only observed in two patients who experienced complete response (CR) after TIL immunotherapy. Conclusions: HPV ccfDNA represents a promising tumor marker for noninvasive HPV genotyping and may be used in selecting patients for HPV type-specific T-cell-based immunotherapies. It may also have value in detecting antitumor activity of therapeutic agents and in the long-term follow-up of cervical cancer patients in remission. Clin Cancer Res; 23(22); 6856-62. ©2017 AACR . ©2017 American Association for Cancer Research.
Kim, Dai-Jin; Park, Byung Lae; Yoon, Sujung; Lee, Hae-Kook; Joe, Keun-Ho; Cheon, Young-Hoon; Gwon, Do-Hoon; Cho, Sung-Nam; Lee, Hye Won; NamGung, Suk; Shin, Hyoung Doo
2007-06-15
Multiple dopamine receptors in the dopaminergic system may be prime candidates for genetic influence on alcohol abuse and dependence due to their involvement in reward and reinforcing mechanisms. Genetic polymorphisms in dopamine receptor genes are believed to influence the development and/or severity of alcoholism. To examine the genetic effects of the Dopamine Receptor D1 (DRD) gene family (DRD1-DRD5) in the Korean population, 11 polymorphisms in the DRD gene family were genotyped and analyzed in 535 alcohol-dependent subjects and 273 population controls. Although none of the polymorphisms of DRD1-5 genes were found to be associated with the risk of alcoholism, one 5' UTR polymorphism in the DRD1 (DRD1-48A>G) gene was significantly associated with severity of alcohol-related problem, as measured by the Alcohol Use Disorders Identification Test (AUDIT) in a gene dose-dependent manner, i.e., 24.37 (+/-8.19) among patients with -48A/A genotype, 22.37 (+/-9.49) among those with -48A/G genotype, and 17.38 (+/-8.28) among those with -48G/G genotype (P=0.002). The genetic effects of DRD1-48A>G were further analyzed with other phenotypes among alcohol-dependent subjects. Interestingly, the DRD1-48A>A genotype was also found to be associated with novelty seeking (NC), harm avoidance (HA), and persistence (P) (P =0.01, 0.02, and 0.003, respectively). The information derived from this study could be valuable for understanding the genetic factors involved in alcoholic phenotypes and genetic distribution of the DRD gene family, and could facilitate further investigation in other ethnic groups.
Janssen, Paddy KC; van Schaik, Ron; Olivier, Berend; Waldinger, Marcel D
2014-01-01
It has been postulated that the persistent short intravaginal ejaculation latency time (IELT) of men with lifelong premature ejaculation (LPE) is related to 5-hydroxytryptamine (HT)2C receptor functioning. The aim of this study was to investigate the relationship of Cys23Ser 5-HT2C receptor gene polymorphism and the duration of IELT in men with LPE. Therefore, a prospective study was conducted in 64 Dutch Caucasian men with LPE. Baseline IELT during coitus was assessed by stopwatch over a 1-month period. All men were genotyped for Cys23Ser 5-HT2C receptor gene polymorphism. Allele frequencies and genotypes of Cys and Ser variants of 5-HT2C receptor gene polymorphism were determined. Association between Cys/Cys and Ser/Ser genotypes and the natural logarithm of the IELT in men with LPE were investigated. As a result, the geometric mean, median and natural mean IELT were 25.2, 27.0, 33.9 s, respectively. Of all men, 20.0%, 10.8%, 23.1% and 41.5% ejaculated within 10, 10–20, 20–30 and 30–60 s after vaginal penetration. Of the 64 men, the Cys/Cys and Ser/Ser genotype frequency for the Cys23Ser polymorphism of the 5-HT2C receptor gene was 81% and 19%, respectively. The geometric mean IELT of the wildtypes (Cys/Cys) is significantly lower (22.6 s; 95% CI 18.3–27.8 s) than in male homozygous mutants (Ser/Ser) (40.4 s; 95% CI 20.3–80.4 s) (P = 0.03). It is concluded that Cys23Ser 5-HT2C receptor gene polymorphism is associated with the IELT in men with LPE. Men with Cys/Cys genotype have shorter IELTs than men with Ser/Ser genotypes. PMID:24799636
Janssen, Paddy Kc; Schaik, Ron van; Olivier, Berend; Waldinger, Marcel D
2014-01-01
It has been postulated that the persistent short intravaginal ejaculation latency time (IELT) of men with lifelong premature ejaculation (LPE) is related to 5-hydroxytryptamine (HT)2C receptor functioning. The aim of this study was to investigate the relationship of Cys23Ser 5-HT2C receptor gene polymorphism and the duration of IELT in men with LPE. Therefore, a prospective study was conducted in 64 Dutch Caucasian men with LPE. Baseline IELT during coitus was assessed by stopwatch over a 1-month period. All men were genotyped for Cys23Ser 5-HT2C receptor gene polymorphism. Allele frequencies and genotypes of Cys and Ser variants of 5-HT2C receptor gene polymorphism were determined. Association between Cys/Cys and Ser/Ser genotypes and the natural logarithm of the IELT in men with LPE were investigated. As a result, the geometric mean, median and natural mean IELT were 25.2, 27.0, 33.9 s, respectively. Of all men, 20.0%, 10.8%, 23.1% and 41.5% ejaculated within 10, 10-20, 20-30 and 30-60 s after vaginal penetration. Of the 64 men, the Cys/Cys and Ser/Ser genotype frequency for the Cys23Ser polymorphism of the 5-HT2C receptor gene was 81% and 19%, respectively. The geometric mean IELT of the wildtypes (Cys/Cys) is significantly lower (22.6 s; 95% CI 18.3-27.8 s) than in male homozygous mutants (Ser/Ser) (40.4 s; 95% CI 20.3-80.4 s) (P = 0.03). It is concluded that Cys23Ser 5-HT2C receptor gene polymorphism is associated with the IELT in men with LPE. Men with Cys/Cys genotype have shorter IELTs than men with Ser/Ser genotypes.
Khalifa, Rania H; Shahin, Rasha Mohamad Hosny; Aboukhalil, Reham Emad Eldin; Marie, Mohamed A; El-Deeb, Amr M; Riad, Nermine Magdi
2017-06-15
Egypt is confronted with the highest hepatitis C virus (HCV) epidemic. Apoptosis and cellular immune responses are crucial to the clearance or persistence of viral infections. This case-control study was carried out to detect whether apoptosis genes single nucleotide polymorphisms (SNPs) confer risk to HCV in a cohort of Egyptian patients and to explore their association with viral load. One hundred and ninety six blood samples were withdrawn from 96 HCV patients and 100 controls. The Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) -1525G>A and FasL-844T>C SNPs were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Hepatitis C viral load was measured using Real time PCR. Results Genotypes distributions of TRAIL -1525G>A and FasL-844 T>C polymorphisms in controls were in accordance with Hardy-Weinberg equilibrium (p>0.05). The study showed a statistically significant difference in the distribution of the TRAIL -1525G>A polymorphism genotypes and the FasL-844 T>C polymorphism genotypes between the HCV patients and the controls (p=0.001 and 0.02 respectively), with association of the -1525GA genotype and -844 TT genotype with increased risk of HCV infection (OR=2.68, 1.942 respectively, 95% CI=1.482-4.846, 1.1-3.43, respectively). No significant association was detected between TRAIL, FasL and the viral load. Our results suggest that the FasL -844T>C SNP is implicated in the susceptibility to HCV in Egyptian patients and firstly report the involvement of TRAIL gene polymorphism in the risk of the disease. Therefore we recommend national programs to delineate genetic factors that may put individuals at risk for contracting HCV. Copyright © 2017 Elsevier B.V. All rights reserved.
An overview of molecular epidemiology of hepatitis B virus (HBV) in India.
Datta, Sibnarayan
2008-12-19
Hepatitis B virus (HBV) is one of the major global public health problems. In India, HBsAg prevalence among general population ranges from 2% to 8%, placing India in intermediate HBV endemicity zone and the number of HBV carriers is estimated to be 50 million, forming the second largest global pool of chronic HBV infections. India is a vast country, comprised of multiracial communities with wide variations in ethnicity and cultural patterns, which is attributable to its geographical location, gene influx due to invasion and/or anthropological migrations in the past. Moreover, recent increase in trade, trafficking and use of illicit drugs has also considerably influenced the epidemiology of HBV, specifically in the eastern and north eastern parts of India. However, data on the molecular epidemiology of HBV in India is scanty. HBV genotypes A and D have been well documented from different parts of mainland India. Interestingly, in addition to genotypes A and D, genotype C having high nucleotide similarity with south East Asian subgenotype Cs/C1 strain, have been detected exclusively from eastern Indian HBV carriers, suggesting a recent introduction. Thus, compared to other parts of India, the molecular epidemiology of HBV is naturally distinct in eastern India. Very recently, taking the advantage of circulation of three distinct HBV genotypes within the population of eastern India, different aspects of HBV molecular epidemiology was studied that revealed very interesting results. In this study, the clinical significance of HBV genotypes, core promoter and precore mutations, possible routes of introduction of HBV genotype C in eastern India, the clinical implications of x gene variability, prevalence of the AFB1 induced p53 gene codon 249 mutation, the transmission potentiality of HBV among asymptomatic/inactive or occult HBV carriers and the genetic variability of HBV persisting in the PBL was investigated. In this manuscript, the information available on the molecular epidemiology of HBV in India has been reviewed and the results of studies among the eastern Indian population have been summarised.
Dvir, Roee; Paloschi, Vera; Canducci, Filippo; Dell'Antonio, Giacomo; Racca, Sara; Caldara, Rossana; Pantaleo, Giuseppe; Clementi, Massimo; Secchi, Antonio
2017-07-27
BK virus (BKV) associated nephropathy (BKVAN) is still an important cause of allograft dysfunction after kidney transplantation (KT). Recent data have shown that the new interferon (IFN)-λ family has been ascribed antiviral properties similar to IFNα, and that the response to IFNλ in kidney is restricted to epithelial cells, suggesting that the IFNλ system evolves as specific protection of the epithelia. We aimed to test the hypothesis of correlation between a single nucleotide polymorphism (C/T dimorphism rs12979860) in the genomic region of IL28B and BKVAN, in patients after KT. Fifty kidney-transplanted patients were included as follow: Group 1 (BKV+/BKVAN+): 11 patients with active BKV- replication and biopsy-proven BKVAN; Group 2 (BKV+/BKVAN-): 22 patients with active BKV- replication but without evidence of BKVAN; Group 3 (BKV-/BKVAN-): 17 patients without evidence of BKV- replication (control group). Here we show that the C/C genotype was statistically higher in group 2 than in group 1 and BKVAN was detected significantly more frequently in patients with C/T and T/T genotypes than in patients with C/C genotype. We therefore propose IL28B polymorphism (rs12979860), as a predictor-marker to differentiate between patients with self-limited, even if persistent, BKV- reactivation and patients with a high risk of progression towards BKVAN, and to modulate the clinical management of these patients accordingly.
Binder, Elisabeth B; Newport, D Jeffrey; Zach, Elizabeth B; Smith, Alicia K; Deveau, Todd C; Altshuler, Lori L; Cohen, Lee S; Stowe, Zachary N; Cubells, Joseph F
2010-07-01
Peripartum major depressive disorder (MDD) is a prevalent psychiatric disorder with potential detrimental consequences for both mother and child. Despite its enormous health care relevance, data regarding genetic predictors of peripartum depression are sparse. The aim of this study was to investigate associations of the serotonin-transporter linked polymorphic region (5-HTTLPR) genotype with peripartum MDD in an at-risk population. Two hundred and seventy four women with a prior history of MDD were genotyped for 5-HTTLPR and serially evaluated in late pregnancy (gestational weeks 31-40), early post-partum (week 1-8) and late post-partum (week 9-24) for diagnosis of a current major depressive episode (MDE) and depressive symptom severity. 5-HTTLPR S-allele carrier status predicted the occurrence of a MDE in the early post-partum period only (OR=5.13, p=0.017). This association persisted despite continued antidepressant treatment. The 5-HTTLPR genotype may be a clinically relevant predictor of early post-partum depression in an at-risk population. Peripartum major depressive disorder is a prevalent psychiatric disorder with potential detrimental consequences for both mother and child. Despite its enormous health care relevance, data regarding genetic predictors of peripartum depression are sparse. The aim of this study was to investigate associations of the serotonin-transporter linked polymorphic region (5-HTTLPR) genotype with peripartum MDD in an at-risk population. Copyright 2009 Elsevier Ltd. All rights reserved.
Imran, Asma; Mirza, Muhammad S.; Shah, Tariq M.; Malik, Kauser A.; Hafeez, Fauzia Y.
2015-01-01
Pakistan is among top three chickpea producing countries but the crop is usually grown on marginal lands without irrigation and fertilizer application which significantly hampers its yield. Soil fertility and inoculation with beneficial rhizobacteria play a key role in nodulation and yield of legumes. Four kabuli and six desi chickpea genotypes were, therefore, evaluated for inoculation response with IAA-producing Ochrobactrum ciceri Ca-34T and nitrogen fixing Mesorhizobium ciceri TAL-1148 in single and co-inoculation in two soils. The soil type 1 was previously unplanted marginal soil having low organic matter, P and N contents compared to soil type 2 which was a fertile routinely legume-cultivated soil. The effect of soil fertility status was pronounced and fertile soil on average, produced 31% more nodules, 62% more biomass and 111% grain yield than marginal soil. Inoculation either with O. ciceri alone or its co-inoculation with M. ciceri produced on average higher nodules (42%), biomass (31%), grains yield (64%) and harvest index (72%) in both chickpea genotypes over non-inoculated controls in both soils. Soil 1 showed maximum relative effectiveness of Ca-34T inoculation for kabuli genotypes while soil 2 showed for desi genotypes except B8/02. Desi genotype B8/02 in soil type 1 and Pb-2008 in soil type 2 showed significant yield increase as compared to respective un-inoculated controls. Across bacterial inoculation treatments, grain yield was positively correlated to growth and yield contributing parameters (r = 0.294* to 0.838*** for desi and r = 0.388* to 0.857** for kabuli). PCA and CAT-PCA analyses clearly showed a site-specific response of genotype x bacterial inoculation. Furthermore, the inoculated bacterial strains were able to persist in the rhizosphere showing colonization on root and within nodules. Present study shows that plant growth promoting rhizobacteria (PGPR) inoculation should be integrated with national chickpea breading program in Pakistan especially for marginal soils. Furthermore, the study shows the potential of phytohormone producing strain Ca-34T as promising candidate for development of biofertilizer alongwith nodulating strains to get sustainable yield of kabuli and desi chickpea with minimum inputs at marginal land. PMID:26379638
Tang, Xun; Guo, Song; Sun, Hongqiang; Song, Xuemei; Jiang, Zuonin; Sheng, Lixiang; Zhou, Dongfeng; Hu, Yonghua; Chen, Dafang
2009-05-01
Nicotine is the major psychoactive ingredient in tobacco, and is responsible for dependence through the nicotine-stimulated reward pathway mediated by the central dopaminergic system. Consequently, genetic polymorphisms in both nicotine metabolism and dopamine catabolism genes may influence smoking behavior, and interact with each other resulting in risk modulation. In this study, we investigated the association and multilocus gene-gene interactions of cytochrome P450 2A6 (CYP2A6), dopamine beta-hydroxylase (DBH), catechol O-methyl transferase (COMT), and monoamine oxidase A (MAOA) polymorphisms with smoking behavior in a community-based Chinese male population. The polymorphisms were genotyped in 203 current smokers, 66 former smokers, and 102 never smokers. Multivariate logistic regression models and the multifactor dimensionality reduction method were used to analyze the association and multilocus gene-gene interactions. Statistically significant trends were shown for increased risk of smoking initiation in participants with CYP2A6*1B/CYP2A6*1B genotypes compared with those with CYP2A6*1A/CYP2A6*1A genotypes [odds ratio (OR)=3.5, 95% confidence interval (CI)= 1.5-8.1], and participants with CYP2A6*1/CYP2A6*1 genotypes were at higher risk of smoking initiation (OR=2.4, 95% CI=1.2-4.5) and smoking persistence (OR=4.0, 95% CI=1.5-10.3) than those who have CYP2A6*4C genotypes. Moreover, the best model involved a gene-gene interaction between MAOA and CYP2A6 was characterized by the multifactor dimensionality reduction method (64.11% accuracy, P<0.001), and indicated that carriers of the combined 1460 T/O genotype for MAOA EcoRV and CYP2A6*1/CYP2A6*1 genotypes were at higher risk of smoking (OR=15.4, 95% CI=4.5-52.5). These findings suggested a substantial influence of CYP2A6 polymorphism as well as the interaction with MAOA resulting in risk modulation on smoking behavior in Chinese male population.
Hemagglutinin-specific neutralization of subacute sclerosing panencephalitis viruses
Muller, Claude P.; Russell, Stephen J.
2018-01-01
Subacute sclerosing panencephalitis (SSPE) is a progressive, lethal complication of measles caused by particular mutants of measles virus (MeV) that persist in the brain despite high levels of neutralizing antibodies. We addressed the hypothesis that antigenic drift is involved in the pathogenetic mechanism of SSPE by analyzing antigenic alterations in the MeV envelope hemagglutinin protein (MeV-H) found in patients with SSPE in relation to major circulating MeV genotypes. To this aim, we obtained cDNA for the MeV-H gene from tissue taken at brain autopsy from 3 deceased persons with SSPE who had short (3–4 months, SMa79), average (3.5 years, SMa84), and long (18 years, SMa94) disease courses. Recombinant MeVs with a substituted MeV-H gene were generated by a reverse genetic system. Virus neutralization assays with a panel of anti-MeV-H murine monoclonal antibodies (mAbs) or vaccine-immunized mouse anti-MeV-H polyclonal sera were performed to determine the antigenic relatedness. Functional and receptor-binding analysis of the SSPE MeV-H showed activity in a SLAM/nectin-4–dependent manner. Similar to our panel of wild-type viruses, our SSPE viruses showed an altered antigenic profile. Genotypes A, G3, and F (SSPE case SMa79) were the exception, with an intact antigenic structure. Genotypes D7 and F (SSPE SMa79) showed enhanced neutralization by mAbs targeting antigenic site IIa. Genotypes H1 and the recently reported D4.2 were the most antigenically altered genotypes. Epitope mapping of neutralizing mAbs BH015 and BH130 reveal a new antigenic site on MeV-H, which we designated Φ for its intermediate position between previously defined antigenic sites Ia and Ib. We conclude that SSPE-causing viruses show similar antigenic properties to currently circulating MeV genotypes. The absence of a direct correlation between antigenic changes and predisposition of a certain genotype to cause SSPE does not lend support to the proposed antigenic drift as a pathogenetic mechanism in SSPE. PMID:29466428
Hemagglutinin-specific neutralization of subacute sclerosing panencephalitis viruses.
Muñoz-Alía, Miguel Ángel; Muller, Claude P; Russell, Stephen J
2018-01-01
Subacute sclerosing panencephalitis (SSPE) is a progressive, lethal complication of measles caused by particular mutants of measles virus (MeV) that persist in the brain despite high levels of neutralizing antibodies. We addressed the hypothesis that antigenic drift is involved in the pathogenetic mechanism of SSPE by analyzing antigenic alterations in the MeV envelope hemagglutinin protein (MeV-H) found in patients with SSPE in relation to major circulating MeV genotypes. To this aim, we obtained cDNA for the MeV-H gene from tissue taken at brain autopsy from 3 deceased persons with SSPE who had short (3-4 months, SMa79), average (3.5 years, SMa84), and long (18 years, SMa94) disease courses. Recombinant MeVs with a substituted MeV-H gene were generated by a reverse genetic system. Virus neutralization assays with a panel of anti-MeV-H murine monoclonal antibodies (mAbs) or vaccine-immunized mouse anti-MeV-H polyclonal sera were performed to determine the antigenic relatedness. Functional and receptor-binding analysis of the SSPE MeV-H showed activity in a SLAM/nectin-4-dependent manner. Similar to our panel of wild-type viruses, our SSPE viruses showed an altered antigenic profile. Genotypes A, G3, and F (SSPE case SMa79) were the exception, with an intact antigenic structure. Genotypes D7 and F (SSPE SMa79) showed enhanced neutralization by mAbs targeting antigenic site IIa. Genotypes H1 and the recently reported D4.2 were the most antigenically altered genotypes. Epitope mapping of neutralizing mAbs BH015 and BH130 reveal a new antigenic site on MeV-H, which we designated Φ for its intermediate position between previously defined antigenic sites Ia and Ib. We conclude that SSPE-causing viruses show similar antigenic properties to currently circulating MeV genotypes. The absence of a direct correlation between antigenic changes and predisposition of a certain genotype to cause SSPE does not lend support to the proposed antigenic drift as a pathogenetic mechanism in SSPE.
Vermont, Clementien L.; Hartwig, Nico G.; Fleer, André; de Man, Peter; Verbrugh, Henri; van den Anker, John; de Groot, Ronald; van Belkum, Alex
1998-01-01
From 1 January 1995 until 1 January 1996, we studied the molecular epidemiology of blood isolates of coagulase-negative staphylococci (CoNS) in the Neonatal Intensive Care Units (NICUs) of the Sophia Children’s Hospital (SCH; Rotterdam, The Netherlands) and the Wilhelmina Children’s Hospital (WCH; Utrecht, The Netherlands). The main goal of the present study was to detect putatively endemic clones of CoNS persisting in these NICUs. Pulsed-field gel electrophoresis was used to detect the possible presence of endemic clones of clinical significance. In addition, clinical data of patients in the SCH were analyzed retrospectively to identify risk factors for the acquisition of positive blood cultures. In both centers, endemic CoNS clones were persistently present. Thirty-three percent of the bacterial isolates derived from blood cultures in the SCH belonged to a single genotype. In the WCH, 45% of all bacterial strains belonged to a single clone. These clones were clearly different from each other, which implies that site specificity is involved. Interestingly, we observe that the clonal type in the SCH differed significantly from the incidentally occurring strains with respect to both the average pH and partial CO2 pressure of the patient’s blood at the time of bacterial culture. We found that the use of intravascular catheters, low gestational age, and a long hospital stay were important risk factors for the development of a putative CoNS infection. When the antibiotic susceptibility of the bacterial isolates was assessed, a clear correlation between the nature of the antibiotics most frequently used as a first line of defense versus the resistance profile was observed. We conclude that the intensive use of antibiotics in an NICU setting with highly susceptible patients causes selection of multiresistant clones of CoNS which subsequently become endemic. PMID:9705379
Repeat-Associated Plasticity in the Helicobacter pylori RD Gene Family▿ †
Shak, Joshua R.; Dick, Jonathan J.; Meinersmann, Richard J.; Perez-Perez, Guillermo I.; Blaser, Martin J.
2009-01-01
The bacterium Helicobacter pylori is remarkable for its ability to persist in the human stomach for decades without provoking sterilizing immunity. Since repetitive DNA can facilitate adaptive genomic flexibility via increased recombination, insertion, and deletion, we searched the genomes of two H. pylori strains for nucleotide repeats. We discovered a family of genes with extensive repetitive DNA that we have termed the H. pylori RD gene family. Each gene of this family is composed of a conserved 3′ region, a variable mid-region encoding 7 and 11 amino acid repeats, and a 5′ region containing one of two possible alleles. Analysis of five complete genome sequences and PCR genotyping of 42 H. pylori strains revealed extensive variation between strains in the number, location, and arrangement of RD genes. Furthermore, examination of multiple strains isolated from a single subject's stomach revealed intrahost variation in repeat number and composition. Despite prior evidence that the protein products of this gene family are expressed at the bacterial cell surface, enzyme-linked immunosorbent assay and immunoblot studies revealed no consistent seroreactivity to a recombinant RD protein by H. pylori-positive hosts. The pattern of repeats uncovered in the RD gene family appears to reflect slipped-strand mispairing or domain duplication, allowing for redundancy and subsequent diversity in genotype and phenotype. This novel family of hypervariable genes with conserved, repetitive, and allelic domains may represent an important locus for understanding H. pylori persistence in its natural host. PMID:19749042
Repeat-associated plasticity in the Helicobacter pylori RD gene family.
Shak, Joshua R; Dick, Jonathan J; Meinersmann, Richard J; Perez-Perez, Guillermo I; Blaser, Martin J
2009-11-01
The bacterium Helicobacter pylori is remarkable for its ability to persist in the human stomach for decades without provoking sterilizing immunity. Since repetitive DNA can facilitate adaptive genomic flexibility via increased recombination, insertion, and deletion, we searched the genomes of two H. pylori strains for nucleotide repeats. We discovered a family of genes with extensive repetitive DNA that we have termed the H. pylori RD gene family. Each gene of this family is composed of a conserved 3' region, a variable mid-region encoding 7 and 11 amino acid repeats, and a 5' region containing one of two possible alleles. Analysis of five complete genome sequences and PCR genotyping of 42 H. pylori strains revealed extensive variation between strains in the number, location, and arrangement of RD genes. Furthermore, examination of multiple strains isolated from a single subject's stomach revealed intrahost variation in repeat number and composition. Despite prior evidence that the protein products of this gene family are expressed at the bacterial cell surface, enzyme-linked immunosorbent assay and immunoblot studies revealed no consistent seroreactivity to a recombinant RD protein by H. pylori-positive hosts. The pattern of repeats uncovered in the RD gene family appears to reflect slipped-strand mispairing or domain duplication, allowing for redundancy and subsequent diversity in genotype and phenotype. This novel family of hypervariable genes with conserved, repetitive, and allelic domains may represent an important locus for understanding H. pylori persistence in its natural host.
Færch, Louise H; Sejling, Anne-Sophie; Lajer, Maria; Tarnow, Lise; Thorsteinsson, Birger; Pedersen-Bjergaard, Ulrik
2015-06-01
Carrying the D-allele of the angiotensin-converting enzyme (ACE) I/D polymorphism and high ACE activity are prognostic factors in diabetic nephropathy, which predicts mortality in type 1 diabetes. We studied the association between the ACE D-allele and ACE phenotype and long-term all-cause mortality in three single-institution outpatient cohorts. Genotype-based analyses were performed in 269 patients from Hillerød Hospital (HIH) (follow-up: 12 years) and in 439 patients with diabetic nephropathy and 437 patients with persistent normoalbuminuria from the Steno Diabetes Center (SDC) (follow-up: 9.5 years). Patients not on renin-angiotensin system (RAS)-blocking treatment were included in analyses of serum ACE activity (HIH: n = 208) and plasma ACE concentration (SDC: n=269). In the HIH cohort, carrying a D-allele was associated with excess mortality (hazard ratio (HR) = 4.0 (95% confidence interval (CI) 1.0-16)), but not in the SDC cohorts. At HIH, serum ACE activity was associated with excess mortality (HR=1.04 (95% CI 1.0-1.1 per unit increase)), but in the SDC cohort plasma ACE concentration was not. In unselected patients with type 1 diabetes, carrying the ACE D-allele and high spontaneous serum ACE activity were associated with 12-year excess mortality. These findings could not be reproduced in two other cohorts with persistent normoalbuminuria or diabetic nephropathy. © The Author(s) 2013.
Suzuki, Saori; Mori, Ken-Ichi; Higashino, Atsunori; Iwasaki, Yuki; Yasutomi, Yasuhiro; Maki, Noboru; Akari, Hirofumi
2016-01-01
The development of effective hepatitis C virus (HCV) vaccines is essential for the prevention of further HCV dissemination, especially in developing countries. Therefore the aim of this study is to establish a feasible and immunocompetent surrogate animal model of HCV infection that will help in evaluation of the protective efficacy of newly developing HCV vaccine candidates. To circumvent the narrow host range of HCV, an HCV genotype 1b-based chimeric clone carrying E1, E2 and p6 regions from GB virus B (GBV-B), which is closely related to HCV, was generated. The chimera between HCV and GBV-B, named HCV/G, replicated more efficiently as compared with the HCV clone in primary marmoset hepatocytes. Furthermore, it was found that the chimera persistently replicated in a tamarin for more than 2 years after intrahepatic inoculation of the chimeric RNA. Although relatively low (<200 copies/mL), the viral RNA loads in plasma were detectable intermittently during the observation period. Of note, the chimeric RNA was found in the pellet fraction obtained by ultracentrifugation of the plasma at 73 weeks, indicating production of the chimeric virus. Our results will help establish a novel non-human primate model for HCV infection on the basis of the HCV/G chimera in the major framework of the HCV genome. © 2015 The Societies and John Wiley & Sons Australia, Ltd.
Detection of BVDV persistently infected animals in Belgium: evaluation of the strategy implemented.
Letellier, C; De Meulemeester, L; Lomba, M; Mijten, E; Kerkhofs, P
2005-11-15
Until now, no official bovine virus diarrhea virus (BVDV) control program has been implemented in Belgium. The only legislation dealing with the detection of BVDV-infected animals concerns the purchase of animals. A strategy of control, based on the identification and elimination of persistently infected (PI) animals and the vaccination of cows before insemination has been designed in both the Northern and the Southern part of the country. The strategy of detection of PI animals relies on PCR testing of pools of blood. Individual blood samples corresponding to the positive pools are then tested by BVDV-antigen ELISA. A first evaluation of the measures already applied in Belgium is presented. Data obtained in 2003 are presented and discussed regarding the validation of the laboratory strategy, the prevalence of positive herds, the genotype of circulating viruses, the outcome of antigen positive animals and the need for improvement of the current legislation.
Tohma, Kentaro; Lepore, Cara J; Ford-Siltz, Lauren A; Parra, Gabriel I
2017-01-01
Norovirus is the leading cause of acute gastroenteritis worldwide. For over two decades, a single genotype (GII.4) has been responsible for most norovirus-associated cases. However, during the winter of 2014 to 2015, the GII.4 strains were displaced by a rarely detected genotype (GII.17) in several countries of the Asian continent. Moreover, during the winter of 2016 to 2017, the GII.2 strain reemerged as predominant in different countries worldwide. This reemerging GII.2 strain is a recombinant virus that presents a GII.P16 polymerase genotype. In this study, we investigated the evolutionary dynamics of GII.2 to determine the mechanism of this sudden emergence in the human population. The phylogenetic analyses indicated strong linear evolution of the VP1-encoding sequence, albeit with minor changes in the amino acid sequence over time. Without major genetic differences among the strains, a clustering based on the polymerase genotype was observed in the tree. This association did not affect the substitution rate of the VP1. Phylogenetic analyses of the polymerase region showed that reemerging GII.P16-GII.2 strains diverged into a new cluster, with a small number of amino acid substitutions detected on the surface of the associated polymerase. Thus, besides recombination or antigenic shift, point mutations in nonstructural proteins could also lead to novel properties with epidemic potential in different norovirus genotypes. IMPORTANCE Noroviruses are a major cause of gastroenteritis worldwide. Currently, there is no vaccine or specific antiviral available to treat norovirus disease. Multiple norovirus strains infect humans, but a single genotype (GII.4) has been regarded as the most important cause of viral gastroenteritis outbreaks worldwide. Its persistence and predominance have been explained by the continuous replacement of variants that present new antigenic properties on their capsid protein, thus evading the herd immunity acquired to the previous variants. Over the last three seasons, minor genotypes have displaced the GII.4 viruses as the predominant strains. One of these genotypes, GII.2, reemerged as predominant during 2016 to 2017. Here we show that factors such as minor changes in the polymerase may have driven the reemergence of GII.2 during the last season. A better understanding of norovirus diversity is important for the development of effective treatments against noroviruses.
Carbohydrate maldigestion induces necrotizing enterocolitis in preterm pigs
Thymann, Thomas; Møller, Hanne K.; Stoll, Barbara; Støy, Ann Cathrine F.; Buddington, Randal K.; Bering, Stine B.; Jensen, Bent B.; Olutoye, Oluyinka O.; Siggers, Richard H.; Mølbak, Lars; Sangild, Per T.
2009-01-01
Necrotizing enterocolitis (NEC) remains the most severe gastrointestinal disorder in preterm infants. It is associated with the initiation of enteral nutrition and may be related to immature carbohydrate digestive capacity. We tested the hypothesis that a formula containing maltodextrin vs. a formula containing lactose as the principal source of carbohydrate would predispose preterm pigs to a higher NEC incidence. Cesarean-derived preterm pigs were given total parenteral nutrition for 48 h followed by total enteral nutrition with a lactose-based (n = 11) or maltodextrin-based (n = 11) formula for 36 h. A higher incidence (91% vs. 27%) and severity (score of 3.3 vs. 1.8) of NEC were observed in the maltodextrin than in the lactose group. This higher incidence of NEC in the maltodextrin group was associated with significantly lower activities of lactase, maltase, and aminopeptidase; reduced villus height; transiently reduced in vivo aldohexose uptake; and reduced ex vivo aldohexose uptake capacity in the middle region of the small intestine. Bacterial diversity was low for both diets, but alterations in bacterial composition and luminal concentrations of short-chain fatty acids were observed in the maltodextrin group. In a second study, we quantified net portal absorption of aldohexoses (glucose and galactose) during acute jejunal infusion of a maltodextrin- or a lactose-based formula (n = 8) into preterm pigs. We found lower net portal aldohexose absorption (4% vs. 42%) and greater intestinal recovery of undigested carbohydrate (68% vs. 27%) in pigs acutely perfused with the maltodextrin-based formula than those perfused with the lactose-based formula. The higher digestibility of the lactose than the maltodextrin in the formulas can be attributed to a 5- to 20-fold higher hydrolytic activity of tissue-specific lactase than maltases. We conclude that carbohydrate maldigestion is sufficient to increase the incidence and severity of NEC in preterm pigs. PMID:19808655
Kreikemeier, K K; Harmon, D L; Peters, J P; Gross, K L; Armendariz, C K; Krehbiel, C R
1990-09-01
Twenty (12 Holstein, 8 Longhorn cross) calves (198 kg and 7 mo old) were used in a randomized complete block design to evaluate the effects of dietary forage concentration and feed intake on carbohydrase activities and small intestinal (SI) morphology. Calves were individually fed 90% forage (alfalfa) or a 90% concentrate (50% sorghum: 50% wheat) diet at either one or two times NEm for 140 d and slaughtered; tissues and small intestinal digesta were collected. Increased feed intake increased (P less than .05) pancreatic weight, alpha-amylase and glucoamylase activities in the pancreas, SI length and SI digesta weight. Forage-fed calves gained faster (P less than .01) and had greater (P less than .05) pancreatic protein concentrations, alpha-amylase and glucoamylase activities in the pancreas and greater SI digesta alpha-amylase activities than grain-fed calves did. Increased feed intake increased (P less than .01) mucosal weight/cm small intestine only in forage-fed calves and increased (P less than .05) SI surface/volume only in grain-fed calves. Mucosal weight was greatest (P less than .05) at the terminal ileum, surface/volume was greatest (P less than .05) in the duodenum, and mucosal protein concentration was highest (P less than .05) in the SI mid-section. Mucosal lactase was higher (P less than .05) in proximal segments, whereas mucosal isomaltase was higher in middle and distal segments of the small intestine. For mucosal maltase activity, there was a feed intake x SI sampling site interaction (P less than .05) and for trehalase, a diet x feed intake x SI sampling site interaction (P less than .05). The SI distribution patterns of maltase and isomaltase were similar, as were those of trehalase and lactase. The alpha-amylase activity in the pancreas and SI morphology were influenced greatly by diet composition and feed intake by calves.
Tikkanen, Roope; Ducci, Francesca; Goldman, David; Holi, Matti; Lindberg, Nina; Tiihonen, Jari; Virkkunen, Matti
2010-05-01
A polymorphism in the promoter region of the monoamine oxidase A gene (MAOA) has been shown to alter the effect of persistent drinking and childhood maltreatment on the risk for violent and antisocial behaviors. These findings indicate that MAOA could contribute to inter-individual differences in stress resiliency. Recidivism in severe violent crimes was assessed after 8 years of nonincarcerated follow-up in a male sample of 174 impulsive Finnish alcoholic violent offenders, the majority of whom exhibited antisocial (ASPD) or borderline personality disorder (BPD) or both. We examined whether MAOA genotype alters the effects of heavy drinking and childhood physical abuse (CPA) on the risk for committing impulsive recidivistic violent crimes. Logistic regression analyses showed that both heavy drinking and CPA were significant independent predictors of recidivism in violent behavior (OR 5.2, p = 0.004 and OR 5.3, p = 0.003) among offenders having the high MAOA activity genotype (MAOA-H), but these predictors showed no effect among offenders carrying the low MAOA activity genotype (MAOA-L). Carriers of the MAOA-H allele have a high risk to commit severe recidivistic impulsive violent crimes after exposure to heavy drinking and CPA.
Tikkanen, Roope; Ducci, Francesca; Goldman, David; Holi, Matti; Lindberg, Nina; Tiihonen, Jari; Virkkunen, Matti
2011-01-01
Background A polymorphism in the promoter region of the monoamine oxidase A gene (MAOA) has been shown to alter the effect of persistent drinking and childhood maltreatment on the risk for violent and antisocial behaviors. These findings indicate that MAOA could contribute to inter-individual differences in stress resiliency. Methods Recidivism in severe violent crimes was assessed after 8 years of nonincarcerated follow-up in a male sample of 174 impulsive Finnish alcoholic violent offenders, the majority of whom exhibited antisocial (ASPD) or borderline personality disorder (BPD) or both. We examined whether MAOA genotype alters the effects of heavy drinking and childhood physical abuse (CPA) on the risk for committing impulsive recidivistic violent crimes. Results Logistic regression analyses showed that both heavy drinking and CPA were significant independent predictors of recidivism in violent behavior (OR 5.2, p = 0.004 and OR 5.3, p = 0.003) among offenders having the high MAOA activity genotype (MAOA-H), but these predictors showed no effect among offenders carrying the low MAOA activity genotype (MAOA-L). Conclusion Carriers of the MAOA-H allele have a high risk to commit severe recidivistic impulsive violent crimes after exposure to heavy drinking and CPA. PMID:20201935
Pham, Long V; Ramirez, Santseharay; Gottwein, Judith M; Fahnøe, Ulrik; Li, Yi-Ping; Pedersen, Jannie; Bukh, Jens
2018-06-01
Chronic liver diseases caused by hepatitis C virus (HCV) genotype 6 are prevalent in Asia, and millions of people require treatment with direct-acting antiviral regimens, such as NS5A inhibitor velpatasvir combined with the NS5B polymerase inhibitor sofosbuvir. We developed infectious cell culture models of HCV genotype 6a infection to study the effects of these inhibitors and the development of resistance. The consensus sequences of strains HK2 (MG717925) and HK6a (MG717928), originating from serum of patients with chronic HCV infection, were determined by Sanger sequencing of genomes amplified by reverse-transcription polymerase chain reaction. In vitro noninfectious full-length clones of these 6a strains were subsequently adapted in Huh7.5 cells, primarily by using substitutions identified in JFH1-based Core-NS5A and Core-NS5B genotype 6a recombinants. We studied the efficacy of NS5A and NS5B inhibitors in concentration-response assays. We examined the effects of long-term culture of Huh7.5 cells incubated with velpatasvir and sofosbuvir singly or combined following infection with passaged full-length HK2 or HK6a recombinant viruses. Resistance-associated substitutions (RAS) were identified by Sanger and next-generation sequencing, and their effects on viral fitness and in drug susceptibility were determined in reverse-genetic experiments. Adapted full-length HCV genotype 6a recombinants HK2cc and HK6acc had fast propagation kinetics and high infectivity titers. Compared with an HCV genotype 1a recombinant, HCV genotype 6a recombinants of strains HK2 and HK6a were equally sensitive to daclatasvir, elbasvir, velpatasvir, pibrentasvir, and sofosbuvir, but less sensitive to ledipasvir, ombitasvir, and dasabuvir. Long-term exposure of HCV genotype 6a-infected Huh7.5 cells with a combination of velpatasvir and sofosbuvir resulted in clearance of the virus, but the virus escaped the effects of single inhibitors via emergence of the RAS L31V in NS5A (conferring resistance to velpatasvir) and S282T in NS5B (conferring resistance to sofosbuvir). Engineered recombinant genotype 6a viruses with single RAS mediated resistance to velpatasvir or sofosbuvir. HCV genotype 6a viruses with RAS NS5A-L31V or NS5B-S282T were however, able to propagate and escape in Huh7.5 cells exposed to the combination of velpatasvir and sofosbuvir. Further, HCV genotype 6a with NS5A-L31V was able to propagate and escape in the presence of pibrentasvir with emergence of NS5A-L28S, conferring a high level of resistance to this inhibitor. Strains of HCV genotype 6a isolated from patients can be adapted to propagate in cultured cells, permitting studies of the complete life cycle for this important genotype. The combination of velpatasvir and sofosbuvir is required to block propagation of original HCV genotype 6a, which quickly becomes resistant to single inhibitors via the rapid emergence and persistence of RAS. These features of HCV genotype 6a could compromise treatment. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.
Isolation mediates persistent founder effects on zooplankton colonisation in new temporary ponds
Badosa, Anna; Frisch, Dagmar; Green, Andy J.; Rico, Ciro; Gómez, Africa
2017-01-01
Understanding the colonisation process in zooplankton is crucial for successful restoration of aquatic ecosystems. Here, we analyzed the clonal and genetic structure of the cyclical parthenogenetic rotifer Brachionus plicatilis by following populations established in new temporary ponds during the first three hydroperiods. Rotifer populations established rapidly after first flooding, although colonisation was ongoing throughout the study. Multilocus genotypes from 7 microsatellite loci suggested that most populations (10 of 14) were founded by few clones. The exception was one of the four populations that persisted throughout the studied hydroperiods, where high genetic diversity in the first hydroperiod suggested colonisation from a historical egg bank, and no increase in allelic diversity was detected with time. In contrast, in another of these four populations, we observed a progressive increase of allelic diversity. This population became less differentiated from the other populations suggesting effective gene flow soon after its foundation. Allelic diversity and richness remained low in the remaining two, more isolated, populations, suggesting little gene flow. Our results highlight the complexity of colonisation dynamics, with evidence for persistent founder effects in some ponds, but not in others, and with early immigration both from external source populations, and from residual, historical diapausing egg banks. PMID:28276459
Rochat, E; Manel, S; Deschamps-Cottin, M; Widmer, I; Joost, S
2017-01-01
In a simulation study of genotypes conducted over 100 generations for more than 1600 butterfly’s individuals, we evaluate how the increase of anthropogenic fragmentation and reduction of habitat size along urbanisation gradients (from 7 to 59% of impervious land cover) influences genetic diversity and population persistence in butterfly species. We show that in areas characterised by a high urbanisation rate (>56% impervious land cover), a large decrease of both genetic diversity (loss of 60–80% of initial observed heterozygosity) and population size (loss of 70–90% of individuals) is observed over time. This is confirmed by empirical data available for the mobile butterfly species Pieris rapae in a subpart of the study area. Comparing simulated data for P. rapae with its normal dispersal ability and with a reduced dispersal ability, we also show that a higher dispersal ability can be an advantage to survive in an urban or highly fragmented environment. The results obtained here suggest that it is of high importance to account for population persistence, and confirm that it is crucial to maintain habitat size and connectivity in the context of land-use planning. PMID:28792492
Isolation mediates persistent founder effects on zooplankton colonisation in new temporary ponds
NASA Astrophysics Data System (ADS)
Badosa, Anna; Frisch, Dagmar; Green, Andy J.; Rico, Ciro; Gómez, Africa
2017-03-01
Understanding the colonisation process in zooplankton is crucial for successful restoration of aquatic ecosystems. Here, we analyzed the clonal and genetic structure of the cyclical parthenogenetic rotifer Brachionus plicatilis by following populations established in new temporary ponds during the first three hydroperiods. Rotifer populations established rapidly after first flooding, although colonisation was ongoing throughout the study. Multilocus genotypes from 7 microsatellite loci suggested that most populations (10 of 14) were founded by few clones. The exception was one of the four populations that persisted throughout the studied hydroperiods, where high genetic diversity in the first hydroperiod suggested colonisation from a historical egg bank, and no increase in allelic diversity was detected with time. In contrast, in another of these four populations, we observed a progressive increase of allelic diversity. This population became less differentiated from the other populations suggesting effective gene flow soon after its foundation. Allelic diversity and richness remained low in the remaining two, more isolated, populations, suggesting little gene flow. Our results highlight the complexity of colonisation dynamics, with evidence for persistent founder effects in some ponds, but not in others, and with early immigration both from external source populations, and from residual, historical diapausing egg banks.
Updates on chikungunya epidemiology, clinical disease, and diagnostics.
Sam, I-Ching; Kümmerer, Beate M; Chan, Yoke-Fun; Roques, Pierre; Drosten, Christian; AbuBakar, Sazaly
2015-04-01
Chikungunya virus (CHIKV) is an Aedes-borne alphavirus, historically found in Africa and Asia, where it caused sporadic outbreaks. In 2004, CHIKV reemerged in East Africa and spread globally to cause epidemics, including, for the first time, autochthonous transmission in Europe, the Middle East, and Oceania. The epidemic strains were of the East/Central/South African genotype. Strains of the Asian genotype of CHIKV continued to cause outbreaks in Asia and spread to Oceania and, in 2013, to the Americas. Acute disease, mainly comprising fever, rash, and arthralgia, was previously regarded as self-limiting; however, there is growing evidence of severe but rare manifestations, such as neurological disease. Furthermore, CHIKV appears to cause a significant burden of long-term morbidity due to persistent arthralgia. Diagnostic assays have advanced greatly in recent years, although there remains a need for simple, accurate, and affordable tests for the developing countries where CHIKV is most prevalent. This review focuses on recent important work on the epidemiology, clinical disease and diagnostics of CHIKV.
Sex recombination, and reproductive fitness: an experimental study using Paramecium
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nyberg, D.
1982-08-01
The effect of sex and recombination on reproductive fitness are measured using five wild stocks of Paramecium primaurelia. Among the wild stocks there were highly significant differences in growth rates. No hybrid had as low a fitness as the least fit parental stock. Recombination produced genotypes of higher fitness than those of either parent only in the cross between the two stocks of lowest fitness. The increase in variance of fitness as a result of recombination was almost exclusively attributable to the generation lines with low fitness. The fitness consequences of sexuality and mate choice were stock specific; some individualsmore » leaving the most descendants by inbreeding, others by outcrossing. For most crosses the short-term advantage of sex, if any, accrue from the fusion of different gametes (hybrid vigor) and not from recombination. Since the homozygous genotype with the highest fitnes left the most progeny by inbreeding (no recombination), the persistence of conjugation in P. primaurelia is paradoxical. (JMT)« less
Séne, Papa Diogoye; Park, Danny C.; Neafsey, Daniel E.; Schaffner, Stephen F.; Hamilton, Elizabeth J.; Lukens, Amanda K.; Van Tyne, Daria; Mboup, Souleymane; Sabeti, Pardis C.; Ndiaye, Daouda; Wirth, Dyann F.
2013-01-01
Using parasite genotyping tools, we screened patients with mild uncomplicated malaria seeking treatment at a clinic in Thiès, Senegal, from 2006 to 2011. We identified a growing frequency of infections caused by genetically identical parasite strains, coincident with increased deployment of malaria control interventions and decreased malaria deaths. Parasite genotypes in some cases persisted clonally across dry seasons. The increase in frequency of genetically identical parasite strains corresponded with decrease in the probability of multiple infections. Further, these observations support evidence of both clonal and epidemic population structures. These data provide the first evidence of a temporal correlation between the appearance of identical parasite types and increased malaria control efforts in Africa, which here included distribution of insecticide treated nets (ITNs), use of rapid diagnostic tests (RDTs) for malaria detection, and deployment of artemisinin combination therapy (ACT). Our results imply that genetic surveillance can be used to evaluate the effectiveness of disease control strategies and assist a rational global malaria eradication campaign. PMID:23593309
Genre, J; Reginaldo, F P Santos; Andrade, J Marco de Leon; Lima, F P; da Camara, A V Coutinho; Donadi, E A; Crispim, J C
2016-01-01
H. pylori is a potent pathogen due to its capacity to successfully evade host defence mechanisms. Despite inducing immune responses in infected individuals, sometimes these responses fail to clear the infection and the bacterium establishes a persistent infection leading to chronic inflammation. In this context, we hypothesized that human leucocyte antigen G (HLA-G), a non-classical major histocompatibility complex molecule that has the ability to regulate immune responses both in physiological and in pathological conditions, may play an important role in promoting tolerance and helping H. pylori to subvert host defence and consequently establish a chronic infection. Therefore, we evaluated the expression of HLA-G 14-bp Ins/Del polymorphism in patients harbouring H. pylori infection, as well as their relationship with histological and demographic variables, to gain a better understanding of the actual role of HLA-G and its genetic polymorphisms in bacterial infection. Sixty-eight patients with clinical symptoms suggestive of H. pylori infection were enrolled to assess HLA-G 14-bp Ins/Del polymorphism allele and genotype frequencies. After adjustment for covariates (age and gender), the odds of having the genotype Ins/Ins, compared to Del/Del, were 3.77 times greater among HP+ cases than among controls. These findings suggest that the 14-bp Ins/Ins genotype, already associated with inflammatory and autoimmune diseases as well as some viral and parasitic infections, could confer a greater risk of developing H. pylori infection. © 2015 The Foundation for the Scandinavian Journal of Immunology.
Corbett, Stephen J; McMichael, Anthony J; Prentice, Andrew M
2009-01-01
Worldwide, the high prevalence of the Polycystic Ovary Syndrome (PCOS), a heritable cause of ovarian infertility, is an evolutionary paradox, which provides insight into the susceptibility of well-fed human populations to cardiovascular disease and diabetes. We propose that PCOS, Type 2 diabetes (T2D) and the Metabolic Syndrome are modern phenotypic expressions of a metabolic genotype attuned to the dietary and energetic conditions of the Pleistocene. This metabolic "Fertility First" rather than "Thrifty" genotype persisted at high prevalence throughout the entire agrarian period-from around 12,000 years ago until 1800 AD-primarily, we contend, because it conferred a fertility advantage in an environment defined by chronic and often severe seasonal food shortage. Conversely, we argue that genetic adaptations to a high carbohydrate, low protein agrarian diet, with increased sensitivity to insulin action, were constrained because these adaptations compromised fertility by raising the lower bound of body weight and energy intake optimal for ovulation and reproduction. After 1800, the progressive attainment of dietary energy sufficiency released human populations from this constraint. This release, through the powerful mechanism of fertility selection, increased, in decades rather than centuries, the prevalence of a genotype better suited to carbohydrate metabolism. This putative mechanism for rapid and recent human evolution can explain the lower susceptibility to T2D of today's Europid populations. This hypothesis predicts that the increasing rates of diabetes and cardiovascular disease, which typically accompany economic development, will be tempered by natural, but particularly fertility, selection against the conserved ancestral genotypes that currently underpin them.
Interleukin-1 alpha variation is associated with the risk of developing preeclampsia.
Ghasemi, Masoumeh; Kashani, Elham; Fayyaz, Azadeh; Attar, Marzieh; Shahbazi, Majid
2015-10-01
Preeclampsia is a syndrome that affects 5% of all pregnancies, producing substantial maternal and prenatal morbidity and mortality. Several studies have reported that cytokine genes are associated with the persistence of preeclampsia or the severity of the disease. The aim of this study is to investigate the relationships between the polymorphisms of interleukin-1 alpha-889 (IL-1A) gene and preeclampsia. Genomic DNA was extracted from the peripheral blood of 305 patients with preeclampsia and 325 normal controls from Sayyad Shirazi Hospital of Golestan University. Then subjected to SSP-PCR amplification. STATA software and the chi square test were used for statistic calculations. The frequencies of IL-1A -889 genotypes C/C, T/T and C/T in preeclampsia cases were 34.8%, 8.2%, 57% and in controls were 20.9%, 7.6% and 71.3% respectively. There was a significant 1.5 fold excess frequency in genotype C/C in cases (CI=1.44-3.07, OR=2.1, P=0.0001). There was a significant difference in the frequencies of alleles or genotypes in IL-1A promoter regions between patients with preeclampsia and the control group. Turkomans showed the highest frequency of the C allele and Sistanies had the lowest frequency of the C allele in preeclampsia compared to control groups (CI=1.5-3.9, OR=2.48, P=0.0001). Our findings suggest that the IL-1A-899C/C genotype and C allele are associated with susceptibility to preeclampsia. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Microbial community in persistent apical periodontitis: a 16S rRNA gene clone library analysis.
Zakaria, M N; Takeshita, T; Shibata, Y; Maeda, H; Wada, N; Akamine, A; Yamashita, Y
2015-08-01
To characterize the microbial composition of persistent periapical lesions of root filled teeth using a molecular genetics approach. Apical lesion samples were collected from 12 patients (23-80 years old) who visited the Kyushu University Hospital for apicectomy with persistent periapical lesions associated with root filled teeth. DNA was directly extracted from each sample and the microbial composition was comprehensively analysed using clone library analysis of the 16S rRNA gene. Enterococcus faecalis, Candida albicans and specific fimA genotypes of Porphyromonas gingivalis were confirmed using polymerase chain reaction (PCR) analysis with specific primers. Bacteria were detected in all samples, and the dominant findings were P. gingivalis (19.9%), Fusobacterium nucleatum (11.2%) and Propionibacterium acnes (9%). Bacterial diversity was greater in symptomatic lesions than in asymptomatic ones. In addition, the following bacteria or bacterial combinations were characteristic to symptomatic lesions: Prevotella spp., Treponema spp., Peptostreptococcaceae sp. HOT-113, Olsenella uli, Slackia exigua, Selemonas infelix, P. gingivalis with type IV fimA, and a combination of P. gingivalis, F. nucleatum, and Peptostreptococcaceae sp. HOT-113 and predominance of Streptococcus spp. On the other hand, neither Enterococcus faecalis nor C. albicans were detected in any of the samples. Whilst a diverse bacterial species were observed in the persistent apical lesions, some characteristic patterns of bacterial community were found in the symptomatic lesions. The diverse variation of community indicates that bacterial combinations as a community may cause persistent inflammation in periapical tissues rather than specific bacterial species. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.
Chen, Hui-Chi; Schiffman, Mark; Lin, Ching-Yu; Pan, Mei-Hung; You, San-Lin; Chuang, Li-Chung; Hsieh, Chang-Yao; Liaw, Kai-Li; Hsing, Ann W; Chen, Chien-Jen
2011-09-21
Human papillomavirus (HPV) persistence is the pivotal event in cervical carcinogenesis. We followed a large-scale community-based cohort for 16 years to investigate the role of genotype-specific HPV persistence in predicting cervical cancer including invasive and in situ carcinoma. At the baseline examination in 1991-1992, 11,923 participants (aged 30-65 years) consented to HPV testing and cytology; 6923 participants were reexamined in 1993-1995. For HPV testing, we used a polymerase chain reaction-based assay that detected 39 HPV types. Women who developed cervical cancer were identified from cancer and death registries. Cumulative risks for developing cervical cancer among infected and persistently infected women were calculated by the Kaplan-Meier method. Of 10,123 women who were initially cytologically normal, 68 developed cervical cancer. The 16-year cumulative risks of subsequent cervical cancer for women with HPV16, HPV58 (without HPV16), or other carcinogenic HPV types (without HPV16 or HPV58) were 13.5%, 10.3%, and 4.0%, respectively, compared with 0.26% for HPV-negative women. Women with type-specific persistence of any carcinogenic HPV had greatly increased risk compared with women who were HPV-negative at both visits (hazard ratio = 75.4, 95% confidence interval = 31.8 to 178.9). The cumulative cervical cancer risks following persistent carcinogenic HPV infections increased with age: The risks were 5.5%, 14.4%, and 18.1% for women aged 30-44 years, 45-54 years, and 55 years and older, respectively. However, newly acquired infections were associated with a low risk of cervical cancer regardless of age. HPV negativity was associated with a very low long-term risk of cervical cancer. Persistent detection of HPV among cytologically normal women greatly increased risk. Thus, it is useful to perform repeated HPV testing following an initial positive test.
Jeong, Yechan; Jin, Bora; Lee, Hye Won; Park, Hye Jung; Park, Jun Yong; Kim, Do Young; Han, Kwang-Hyub; Ahn, Sang Hoon; Kim, Seungtaek
2018-05-16
Daclatasvir plus asunaprevir (DCV+ASV) treatment is an all-oral direct-acting antiviral (DAA) therapy for the genotype 1b HCV-infected patients. In this study, we investigated how resistance-associated substitutions (RASs) evolved after treatment failures and assessed the effect of those substitutions on viral fitness. Sequencing of NS5A and NS3 revealed typical RASs after treatment failures. Interestingly, the RASs of NS3 reverted to the wild-type amino acid within one year after treatment failures. However, the RASs of NS5A were stable and did not change. The effect of NS5A and NS3 RASs on viral RNA replication was assessed after mutagenic substitution in the genotype 1b HCV RNA. Among the single substitutions, the effect of D168V was more substantial than the others and the effect of the triple mutant combination (D168V+L31V+Y93H) was the most severe. The RAS at NS5A Y93 affected both viral RNA replication and virus production. Finally, the effect of trans-complementation of NS5A was demonstrated in our co-transfection experiments and these results suggest that such a trans-complementation effect of NS5A may help maintain the NS5A RASs for a long time even after cessation of the DAA treatment. In conclusion, the results from this investigation would help understand the emergence and persistence of RASs. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Prevalence and persistence of Taylorella asinigenitalis in male donkeys.
Donahue, James M; Timoney, Peter J; Carleton, Carla L; Marteniuk, Judy V; Sells, Stephen F; Meade, Barry J
2012-12-07
This study was undertaken to investigate the prevalence of Taylorella asinigenitalis in a subset of the donkey population of Michigan and in other equids on farms on which the organism was identified. Other aims were to further characterize the carrier state in terms of persistence and preferred sites of colonization of T. asinigenitalis in the male donkey as well as determine the genotype of any isolates of the organism. Initial testing of 43 donkeys and 1 mule turned up 4 (9.3%) donkeys culture positive for T. asinigenitalis. The 4 culture-positive donkeys resided on 2 farms accommodating a collective total of 89 equids, of which 23 (25.8%) were confirmed positive for T. asinigenitalis. The positive equid population on the 2 farms comprised 14 (67%) of 21 gelded donkeys, 8 (36.4%) of 22 intact male donkeys, and 1 (25%) of 4 gelded horses. T. asinigenitalis was not isolated from 27 female donkeys, 11 female horses, 2 female mules, 1 male horse, or 1 male mule resident on these premises. Isolations of the bacterium were obtained from a number of male donkeys whenever they were sampled over a span of 33 months; preferential sites of isolation were the urethral fossa (fossa glandis), dorsal diverticulum of the urethral sinus, and terminal urethra. Isolates of T. asinigenitalis from the 23 culture-positive equids comprised 2 genotypes, one identical to the type strain isolated in California in 1997, and the other identical to 2 strains isolated from donkey jacks in Kentucky in 1998. Copyright © 2012 Elsevier B.V. All rights reserved.
Kortenhoeven, Cornell; Joubert, Fourie; Bastos, Armanda D S; Abolnik, Celia
2015-02-22
Extensive focus is placed on the comparative analyses of consensus genotypes in the study of West Nile virus (WNV) emergence. Few studies account for genetic change in the underlying WNV quasispecies population variants. These variants are not discernable in the consensus genome at the time of emergence, and the maintenance of mutation-selection equilibria of population variants is greatly underestimated. The emergence of lineage 1 WNV strains has been studied extensively, but recent epidemics caused by lineage 2 WNV strains in Hungary, Austria, Greece and Italy emphasizes the increasing importance of this lineage to public health. In this study we explored the quasispecies dynamics of minority variants that contribute to cell-tropism and host determination, i.e. the ability to infect different cell types or cells from different species from Next Generation Sequencing (NGS) data of a historic lineage 2 WNV strain. Minority variants contributing to host cell membrane association persist in the viral population without contributing to the genetic change in the consensus genome. Minority variants are shown to maintain a stable mutation-selection equilibrium under positive selection, particularly in the capsid gene region. This study is the first to infer positive selection and the persistence of WNV haplotype variants that contribute to viral fitness without accompanying genetic change in the consensus genotype, documented solely from NGS sequence data. The approach used in this study streamlines the experimental design seeking viral minority variants accurately from NGS data whilst minimizing the influence of associated sequence error.
Millet, J; Berchel, M; Prudenté, F; Streit, E; Bomer, A-G; Schuster, F; Vanhomwegen, J; Paasch, D; Galbert, I; Valery, E; Aga, R; Rastogi, N
2014-05-01
This is the first overview on resistant and multidrug resistant isolates of Mycobacterium tuberculosis circulating in the French Department of the Americas (Guadeloupe, Martinique, and French Guiana) over 17 years (January 1995-December 2011). A total of 1,239 cases were studied: 1,199 new cases (primary and multidrug resistance of 11.8 and 1.6% respectively), and 40 persistent (defined as cases with a previous history of positive culture over 6 months interval and whose spoligotypes remain unchanged), in which significantly higher proportions of resistance to at least isoniazid (22.5%, P = 0.002), rifampicin (20.0%, P < 0.001), and multidrug resistance (17.5%, P < 0.001) were observed as compared to new cases. The 281 spoligotypes obtained showed the presence of five major lineages, T (29.9%), LAM (23.9%), Haarlem (22.1%), EAI (7.1%), and X (6.7%). Two of these lineages, X and LAM, predominate among resistant and multidrug resistant isolates respectively (X: 10.5% of resistant isolates, P = 0.04; LAM: 42.3% of multidrug resistant isolates, P = 0.02). Four of the 19 major spoligo-profiles, corresponding to SIT 20, 64, 45, and 46, were significantly associated with drug resistance. Among them, genotype SIT 20, associated with monoresistance to isoniazid and multidrug resistance, would be actively and persistently in circulation, since 1999, in French Guiana, department in which one may also observe the presence of strains of M. tuberculosis phylogeographically associated to Guiana and Suriname (SIT 131 and SIT 1340).
2012-01-01
Background Women with Human Papilloma Virus (HPV) persistence are characterized by high levels of IL-10 at cervix. We have determined whether polymorphisms of IL-10 gene promoter might be associated with increased risk of squamous intraepithelial cervical lesions (SICL) and whether exist significative differences of IL-10 mRNA expression at cervix and systemic and serum IL-10 protein between SICL cases and non-Cervical Lesions (NCL). Methods Peripheral blood samples from SICL (n = 204) and NCL (n = 166) were used to detect IL-10 promoter polymorphisms at loci -592A/C (rs1800872), -819C/T (rs1800871), -1082A/G (rs1800896), -1352A/G (rs1800893), by allelic discrimination and to evaluate serum IL-10 protein. Cervical epithelial scrapings from NCL and biopsies from SICLs were used for HPV-typing and to evaluate IL-10 mRNA expression level. The systemic and local IL-10 mRNA expression levels were measured by real time-PCR. Genotypic and allelic frequencies of the selected polymorphisms were analyzed by logistic regression, adjusting by age and HPV-genotype, to determine the association with SICL. Results No significant differences were found between genotype frequencies at loci −819, -1082, and −1352. Individuals carrying at least one copy of risk allele A of polymorphism −592 had a two-fold increased risk of developing SICL [adjusted odds ratio (OR), 2.02 (95% CI, 1.26-3.25), p = 0.003], compared to NCL. The IL-10 mRNA expression and serum IL-10 protein, were significantly higher in SICL cases (p < 0.01), being higher in patients carrying the risk allele A. Conclusions The −592 polymorphism is associated with increased risk of SICL and can serve as a marker of genetic susceptibility to SICL among Mexican women. According to IL-10 levels found in SICL, IL-10 can be relevant factor for viral persistence and progression disease. PMID:23148667
Stochastic switching in biology: from genotype to phenotype
NASA Astrophysics Data System (ADS)
Bressloff, Paul C.
2017-03-01
There has been a resurgence of interest in non-equilibrium stochastic processes in recent years, driven in part by the observation that the number of molecules (genes, mRNA, proteins) involved in gene expression are often of order 1-1000. This means that deterministic mass-action kinetics tends to break down, and one needs to take into account the discrete, stochastic nature of biochemical reactions. One of the major consequences of molecular noise is the occurrence of stochastic biological switching at both the genotypic and phenotypic levels. For example, individual gene regulatory networks can switch between graded and binary responses, exhibit translational/transcriptional bursting, and support metastability (noise-induced switching between states that are stable in the deterministic limit). If random switching persists at the phenotypic level then this can confer certain advantages to cell populations growing in a changing environment, as exemplified by bacterial persistence in response to antibiotics. Gene expression at the single-cell level can also be regulated by changes in cell density at the population level, a process known as quorum sensing. In contrast to noise-driven phenotypic switching, the switching mechanism in quorum sensing is stimulus-driven and thus noise tends to have a detrimental effect. A common approach to modeling stochastic gene expression is to assume a large but finite system and to approximate the discrete processes by continuous processes using a system-size expansion. However, there is a growing need to have some familiarity with the theory of stochastic processes that goes beyond the standard topics of chemical master equations, the system-size expansion, Langevin equations and the Fokker-Planck equation. Examples include stochastic hybrid systems (piecewise deterministic Markov processes), large deviations and the Wentzel-Kramers-Brillouin (WKB) method, adiabatic reductions, and queuing/renewal theory. The major aim of this review is to provide a self-contained survey of these mathematical methods, mainly within the context of biological switching processes at both the genotypic and phenotypic levels. However, applications to other examples of biological switching are also discussed, including stochastic ion channels, diffusion in randomly switching environments, bacterial chemotaxis, and stochastic neural networks.
Bianchi, Silvia; Frati, Elena Rosanna; Panatto, Donatella; Martinelli, Marianna; Amicizia, Daniela; Zotti, Carla Maria; Martinese, Morena; Bonanni, Paolo; Boccalini, Sara; Coppola, Rosa Cristina; Masia, Giuseppina; Meloni, Angelo; Castiglia, Paolo; Piana, Andrea; Gasparini, Roberto; Tanzi, Elisabetta
2013-01-01
The introduction of vaccination against Human Papillomavirus (HPV) in adolescent girls in 2006 has focused virological surveillance on this age group. As few studies have evaluated HPV infections in young populations, further data are needed in order to improve and extend prophylactic policy and to monitor epidemiological changes. The present study aimed at evaluating overall and type-specific HPV prevalence in both female and male adolescents in Italy. HPV DNA detection and genotyping was performed on urine samples collected from 870 unvaccinated adolescents (369 females, 501 males, 11-18 years of age) in five cities in Italy. Following DNA extraction by means of a commercial kit (NucliSENS®-miniMAG®, bioMérieux), the L1 gene fragment was PCR amplified and genotyped by restriction fragment length polymorphism analysis. HPV DNA was detected in 1.5% of all samples, and in 3% and 0.4% of samples from females and males, respectively. In approximately 70% of HPV DNA positive adolescents, the infection was due to a single genotype, with 88.9% of genotypes belonging to the HR-clade. The only two HPV-positive boys (14 and 18 years old) had HPV-70 genotype. Only one of the 11 HPV-infected girls was in the 11-14 age-group. HPV prevalence was 4.2% in girls aged 15-18 years and 60% of infections were due to vaccine types HPV-16 or HPV-6/-11. This is one of the few studies, the first conducted in Italy, on HPV infection in adolescents. Urine testing is the easier way of detecting HPV infection in younger populations. Our data revealed a very low HPV prevalence, and no infections were observed in the 12-year-old vaccine target population. The majority of infections were seen in females aged 15-18 years. Overall, more than 50% and 30% of the potentially persistent HPV infections detected in this group could have been prevented by the quadrivalent and the bivalent vaccines, respectively. PMID:24255711
Bianchi, Silvia; Frati, Elena Rosanna; Panatto, Donatella; Martinelli, Marianna; Amicizia, Daniela; Zotti, Carla Maria; Martinese, Morena; Bonanni, Paolo; Boccalini, Sara; Coppola, Rosa Cristina; Masia, Giuseppina; Meloni, Angelo; Castiglia, Paolo; Piana, Andrea; Gasparini, Roberto; Tanzi, Elisabetta
2013-01-01
The introduction of vaccination against Human Papillomavirus (HPV) in adolescent girls in 2006 has focused virological surveillance on this age group. As few studies have evaluated HPV infections in young populations, further data are needed in order to improve and extend prophylactic policy and to monitor epidemiological changes. The present study aimed at evaluating overall and type-specific HPV prevalence in both female and male adolescents in Italy. HPV DNA detection and genotyping was performed on urine samples collected from 870 unvaccinated adolescents (369 females, 501 males, 11-18 years of age) in five cities in Italy. Following DNA extraction by means of a commercial kit (NucliSENS(®)-miniMAG(®), bioMérieux), the L1 gene fragment was PCR amplified and genotyped by restriction fragment length polymorphism analysis. HPV DNA was detected in 1.5% of all samples, and in 3% and 0.4% of samples from females and males, respectively. In approximately 70% of HPV DNA positive adolescents, the infection was due to a single genotype, with 88.9% of genotypes belonging to the HR-clade. The only two HPV-positive boys (14 and 18 years old) had HPV-70 genotype. Only one of the 11 HPV-infected girls was in the 11-14 age-group. HPV prevalence was 4.2% in girls aged 15-18 years and 60% of infections were due to vaccine types HPV-16 or HPV-6/-11. This is one of the few studies, the first conducted in Italy, on HPV infection in adolescents. Urine testing is the easier way of detecting HPV infection in younger populations. Our data revealed a very low HPV prevalence, and no infections were observed in the 12-year-old vaccine target population. The majority of infections were seen in females aged 15-18 years. Overall, more than 50% and 30% of the potentially persistent HPV infections detected in this group could have been prevented by the quadrivalent and the bivalent vaccines, respectively.
Penno, G; Chaturvedi, N; Talmud, P J; Cotroneo, P; Manto, A; Nannipieri, M; Luong, L A; Fuller, J H
1998-09-01
We examined whether the ACE gene insertion/deletion (I/D) polymorphism modulates renal disease progression in IDDM and how ACE inhibitors influence this relationship. The EURODIAB Controlled Trial of Lisinopril in IDDM is a multicenter randomized placebo-controlled trial in 530 nonhypertensive, mainly normoalbuminuric IDDM patients aged 20-59 years. Albumin excretion rate (AER) was measured every 6 months for 2 years. Genotype distribution was 15% II, 58% ID, and 27% DD. Between genotypes, there were no differences in baseline characteristics or in changes in blood pressure and glycemic control throughout the trial. There was a significant interaction between the II and DD genotype groups and treatment on change in AER (P = 0.05). Patients with the II genotype showed the fastest rate of AER progression on placebo but had an enhanced response to lisinopril. AER at 2 years (adjusted for baseline AER) was 51.3% lower on lisinopril than placebo in the II genotype patients (95% CI, 15.7 to 71.8; P = 0.01), 14.8% in the ID group (-7.8 to 32.7; P = 0.2), and 7.7% in the DD group (-36.6 to 37.6; P = 0.7). Absolute differences in AER between placebo and lisinopril at 2 years were 8.1, 1.7, and 0.8 microg/min in the II, ID, and DD groups, respectively. The significant beneficial effect of lisinopril on AER in the II group persisted when adjusted for center, blood pressure, and glycemic control, and also for diastolic blood pressure at 1 month into the study. Progression from normoalbuminuria to microalbuminuria (lisinopril versus placebo) was 0.27 (0.03-2.26; P = 0.2) in the II group, and 1.30 (0.33-5.17; P = 0.7) in the DD group (P = 0.6 for interaction). Knowledge of ACE genotype may be of value in determining the likely impact of ACE inhibitor treatment.
Yang, Xianqin; Tran, Frances; Youssef, Mohamed K; Gill, Colin O
2015-07-01
The possible origin of Escherichia coli found on cuts and trimmings in the breaking facility of a beef packing plant was examined using multiple-locus variable-number tandem repeat analysis. Coliforms and E. coli were enumerated in samples obtained from 160 carcasses that would enter the breaking facility when work commenced and after each of the three production breaks throughout the day, from the conveyor belt before work and after each break, and from cuts and trimmings when work commenced and after each break. Most samples yielded no E. coli, irrespective of the surface types. E. coli was recovered from 7 (<5%) carcasses, at numbers mostly ≤1.0 log CFU/160,000 cm(2). The log total numbers of E. coli recovered from the conveyor belt, cuts, and trimmings were mostly between 1 and 2 log CFU/80,000 cm(2). A total of 554 E. coli isolates were recovered. Multiple-locus variable-number tandem repeat analysis of 327 selected isolates identified 80 distinct genotypes, with 37 (46%) each containing one isolate. However, 28% of the isolates were of genotypes that were recovered from more than one sampling day. Of the 80 genotypes, 65 and 2% were found in one or all four sampling periods throughout the day. However, they represented 23 and 14% of the isolates, respectively. Of the genotypes identified for each surface type, at least one contained ≥9 isolates. No unique genotypes were associated with carcasses, but 10, 17, and 19 were uniquely associated with cuts, trimmings, and the belt, respectively. Of the isolates recovered from cuts, 49, 3, and 19% were of genotypes that were found among isolates recovered from the belt, carcasses, or both the belt and carcasses, respectively. A similar composition was found for isolates recovered from trimmings. These findings show that the E. coli found on cuts and trimmings at this beef packing plant mainly originated from the conveyor belt and that small number of E. coli strains survived the daily cleaning and sanitation process, thus persisting in the plant.
Hussain, Zahid; Das, Bhudev C; Husain, Syed A; Polipalli, Sunil K; Ahmed, Tanzeel; Begum, Nargis; Medhi, Subhash; Verghese, Alice; Raish, Mohammad; Theamboonlers, Apiradee; Poovorawan, Yong; Kar, Premashis
2006-08-07
To undertake analysis of hepatitis A viral load, alanine aminotransferase (ALT), and viral genotypes with duration of viremia, and to correlate these parameters with CD4(+)/ CD8(+) lymphocyte populations that control cell-mediated immunity. Cell counts were carried out using fresh whole blood collected in EDTA vials using a fluorescence activated cell sorter. Hepatitis A virus (HAV) RNA was extracted from blood serum, reverse transcribed into cDNA and quantified by Real-Time polymerase chain reaction and was genotyped. Among 11 patients, 10 could be analyzed completely. Of these, 3 had severe acute hepatitis (s-AH) and the remainder had a self-limited acute hepatitis A (AHA), with one patient with fulminant disease (encephalopathy Grade IV) dying on the 4th d. The ALT level was significantly higher both in AHA (1070.9 +/- 894.3; P = 0.0014) and s-AH (1713.9 +/- 886.3; P = 0.001) compared to normal controls (23.6 +/- 7.2). The prothrombin time in s-AH patients (21.0 +/- 2.0; P = 0.02) was significantly higher than in AHA (14.3 +/- 1.1; P = 0.44). The CD4(+)/CD8(+) ratio in AHA patients (1.17 +/- 0.11; P = 0.22) and s-AH (0.83 +/- 0.12; P = 0.0002) were lower than seen in normal healthy controls (1.52). Self-limited cases had peak viral load at the beginning of analysis while in s-AH patients this occurred at the 15th or 30th d. In acute and severe groups, one patient each belonged to genotype IA, with the remaining 8 cases belonging to genotype IIIA. The only fulminant hepatic failure case belonged to genotype IA. HAV viral load and ALT values collected during the entire course of the self-limited infection were directly correlated but this was not the case for s-AH patients. Based on a small-scale study, the persistently higher viral load of s-AH might be due to diminished cellular immunity and hemolysis. The duration of viremia was dependent on the host, as the viral genotype had no apparent role in clinical outcome of AVH and s-AH cases.
Hussain, Zahid; Das, Bhudev C; Husain, Syed A; Polipalli, Sunil K; Ahmed, Tanzeel; Begum, Nargis; Medhi, Subhash; Verghese, Alice; Raish, Mohammad; Theamboonlers, Apiradee; Poovorawan, Yong; Kar, Premashis
2006-01-01
AIM: To undertake analysis of hepatitis A viral load, alanine aminotransferase (ALT), and viral genotypes with duration of viremia, and to correlate these parameters with CD4+/ CD8+ lymphocyte populations that control cell-mediated immunity. METHODS: Cell counts were carried out using fresh whole blood collected in EDTA vials using a fluorescence activated cell sorter. Hepatitis A virus (HAV) RNA was extracted from blood serum, reverse transcribed into cDNA and quantified by Real-Time polymerase chain reaction and was genotyped. RESULTS: Among 11 patients, 10 could be analyzed completely. Of these, 3 had severe acute hepatitis (s-AH) and the remainder had a self-limited acute hepatitis A (AHA), with one patient with fulminant disease (encephalopathy Grade IV) dying on the 4th d. The ALT level was significantly higher both in AHA (1070.9 ± 894.3; P = 0.0014) and s-AH (1713.9 ± 886.3; P = 0.001) compared to normal controls (23.6 ± 7.2). The prothrombin time in s-AH patients (21.0 ± 2.0; P = 0.02) was significantly higher than in AHA (14.3 ± 1.1; P = 0.44). The CD4+/CD8+ ratio in AHA patients (1.17 ± 0.11; P = 0.22) and s-AH (0.83 ± 0.12; P = 0.0002) were lower than seen in normal healthy controls (1.52). Self-limited cases had peak viral load at the beginning of analysis while in s-AH patients this occurred at the 15th or 30th d. In acute and severe groups, one patient each belonged to genotype IA, with the remaining 8 cases belonging to genotype IIIA. The only fulminant hepatic failure case belonged to genotype IA. HAV viral load and ALT values collected during the entire course of the self-limited infection were directly correlated but this was not the case for s-AH patients. CONCLUSION: Based on a small-scale study, the persistently higher viral load of s-AH might be due to diminished cellular immunity and hemolysis. The duration of viremia was dependent on the host, as the viral genotype had no apparent role in clinical outcome of AVH and s-AH cases. PMID:16937439
Azuma, Junichi; Ohno, Masako; Kubota, Ryuji; Yokota, Soichiro; Nagai, Takayuki; Tsuyuguchi, Kazunari; Okuda, Yasuhisa; Takashima, Tetsuya; Kamimura, Sayaka; Fujio, Yasushi; Kawase, Ichiro
2013-05-01
This study is a pharmacogenetic clinical trial designed to clarify whether the N-acetyltransferase 2 gene (NAT2) genotype-guided dosing of isoniazid improves the tolerability and efficacy of the 6-month four-drug standard regimen for newly diagnosed pulmonary tuberculosis. In a multicenter, parallel, randomized, and controlled trial with a PROBE design, patients were assigned to either conventional standard treatment (STD-treatment: approx. 5 mg/kg of isoniazid for all) or NAT2 genotype-guided treatment (PGx-treatment: approx. 7.5 mg/kg for patients homozygous for NAT2 4: rapid acetylators; 5 mg/kg, patients heterozygous for NAT2 4: intermediate acetylators; 2.5 mg/kg, patients without NAT2 4: slow acetylators). The primary outcome included incidences of 1) isoniazid-related liver injury (INH-DILI) during the first 8 weeks of therapy, and 2) early treatment failure as indicated by a persistent positive culture or no improvement in chest radiographs at the 8th week. One hundred and seventy-two Japanese patients (slow acetylators, 9.3 %; rapid acetylators, 53.5 %) were enrolled in this trial. In the intention-to-treat (ITT) analysis, INH-DILI occurred in 78 % of the slow acetylators in the STD-treatment, while none of the slow acetylators in the PGx-treatment experienced either INH-DILI or early treatment failure. Among the rapid acetylators, early treatment failure was observed with a significantly lower incidence rate in the PGx-treatment than in the STD-treatment (15.0 % vs. 38 %). Thus, the NAT2 genotype-guided regimen resulted in much lower incidences of unfavorable events, INH-DILI or early treatment failure, than the conventional standard regimen. Our results clearly indicate a great potential of the NAT2 genotype-guided dosing stratification of isoniazid in chemotherapy for tuberculosis.
Thibault, Vincent; Gaudy-Graffin, Catherine; Colson, Philippe; Gozlan, Joël; Schnepf, Nathalie; Trimoulet, Pascale; Pallier, Coralie; Saune, Karine; Branger, Michel; Coste, Marianne; Thoraval, Francoise Roudot
2013-03-15
Chronic hepatitis B (CHB) is a clinical concern in human immunodeficiency virus (HIV)-infected individuals due to substantial prevalence, difficulties to treat, and severe liver disease outcome. A large nationwide cross-sectional multicentre analysis of HIV-HBV co-infected patients was designed to describe and identify parameters associated with virological and clinical outcome of CHB in HIV-infected individuals with detectable HBV viremia. A multicenter collaborative cross-sectional study was launched in 19 French University hospitals distributed through the country. From January to December 2007, HBV load, genotype, clinical and epidemiological characteristics of 223 HBV-HIV co-infected patients with an HBV replication over 1000 IU/mL were investigated. Patients were mostly male (82%, mean age 42 years). Genotype distribution (A 52%; E 23.3%; D 16.1%) was linked to risk factors, geographic origin, and co-infection with other hepatitis viruses. This genotypic pattern highlights divergent contamination event timelines by HIV and HBV viruses. Most patients (74.7%) under antiretroviral treatment were receiving a drug with anti-HBV activity, including 47% receiving TDF. Genotypic lamivudine-resistance detected in 26% of the patients was linked to duration of lamivudine exposure, age, CD4 count and HIV load. Resistance to adefovir (rtA181T/V) was detected in 2.7% of patients. Advanced liver lesions were observed in 54% of cases and were associated with an older age and lower CD4 counts but not with viral load or genotype. Immune escape HBsAg variants were seldom detected. Despite the detection of advanced liver lesions in most patients, few were not receiving anti-HBV drugs and for those treated with the most potent anti-HBV drugs, persistent replication suggested non-optimal adherence. Heterogeneity in HBV strains reflects epidemiological differences that may impact liver disease progression. These findings are strong arguments to further optimize clinical management and to promote vaccination in HIV-infected patients.
Hamdy, Shaimaa; Osman, Ahmed M; Zakaria, Zainab A; Galal, Iman; Sobhy, Maha; Hashem, Mohamed; Allam, Walaa R; Abdel-Samiee, Mohamed; Rewisha, Eman; Waked, Imam; Abdelwahab, Sayed F
2018-06-02
Toll-like receptors (TLRs) give the innate immune system a considerable specificity for a large range of pathogens. TLR3 detects dsRNA of viruses while TLR9 recognizes bacterial and viral unmethylated CpG motifs. This study examined whether there is a potential association between single-nucleotide polymorphisms (SNPs) in the TLR3.rs3775290 (c.1377C/T), TLR9.rs5743836 (-1237T→C) and TLR9.rs352140 (G2848A) genes and HCV infection among Egyptian patients and healthcare workers (HCWs). We enrolled 546 subjects (409 HCWs and 137 patients) divided into four groups: group 1 included 265 seronegative, aviremic subjects; group 2 included 25 seronegative, viremic subjects; group 3 included 87 subjects with spontaneously resolved HCV infection; and group 4 included 169 chronic HCV patients. All subjects were genotyped for TLR3.rs3775290, TLR9.rs5743836 and TLR9.rs352140 SNPs by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis. TLR3.rs3775290 "CC" genotype was associated with chronic HCV infection, where there was a significantly greater frequency of this genotype among chronic patients when compared to subjects with spontaneously resolved infection (63.9% vs. 51.9%; p = 0.033; OR = 1.639 and 95% CI = 0.94-2.84). However, this SNP did not correlate with the HCV RNA load among the chronic subjects (p > 0.05). There was no significant difference in TLR9.rs5743836 and TLR9.rs352140 genotype distribution between groups (p > 0.05). Lack of association between the three SNPs was found, as the three SNPs are located on two different chromosomes. In conclusion, the TLR3.rs3775290 "CC" genotype was associated with HCV chronicity, while the TLR9 gene may not play a major role in HCV infection.
Mendez, Sean; Watanabe, Louis; Hill, Rachel; Owens, Meredith; Moraczewski, Jason; Rowe, Glenn C.; Riddle, Nicole C.
2016-01-01
Obesity is one of the dramatic health issues affecting developed and developing nations, and exercise is a well-established intervention strategy. While exercise-by-genotype interactions have been shown in humans, overall little is known. Using the natural negative geotaxis of Drosophila melanogaster, an important model organism for the study of genetic interactions, a novel exercise machine, the TreadWheel, can be used to shed light on this interaction. The mechanism for inducing exercise with the TreadWheel is inherently gentle, thus minimizing possible confounding effects of other stressors. Using this machine, we were able to assess large cohorts of adult flies from eight genetic lines for their response to exercise after one week of training. We measured their triglyceride, glycerol, protein, glycogen, glucose content, and body weight, as well as their climbing ability and feeding behavior in response to exercise. Exercised flies showed decreased stored triglycerides, glycogen, and body weight, and increased stored protein and climbing ability. In addition to demonstrating an overall effect of TreadWheel exercise on flies, we found significant interactions of exercise with genotype, sex, or genotype-by-sex effects for most of the measured phenotypes. We also observed interaction effects between exercise, genotype, and tissue (abdomen or thorax) for metabolite profiles, and those differences can be partially linked to innate differences in the flies' persistence in maintaining activity during exercise bouts. In addition, we assessed gene expression levels for a panel of 13 genes known to be associated with respiratory fitness and found that many responded to exercise. With this study, we have established the TreadWheel as a useful tool to study the effect of exercise in flies, shown significant genotype-specific and sex-specific impacts of exercise, and have laid the ground work for more extensive studies of how genetics, sex, environment, and aging interact with exercise to influence metabolic fitness in Drosophila. PMID:27736996
Stanton, Jeffrey J.; Zong, Jian-Chao; Eng, Crystal; Howard, Lauren; Flanagan, Joe; Stevens, Martina; Schmitt, Dennis; Wiedner, Ellen; Graham, Danielle; Junge, Randall E.; Weber, Martha A.; Fischer, Martha; Mejia, Alicia; Tan, Jie; Latimer, Erin; Herron, Alan; Hayward, Gary S.; Ling, Paul D.
2013-01-01
Elephant endotheliotropic herpesviruses (EEHVs) can cause fatal hemorrhagic disease in juvenile Asian elephants (Elephas maximus); however, sporadic shedding of virus in trunk washes collected from healthy elephants also has been detected. Data regarding the relationship of viral loads in blood compared with trunk washes are lacking, and questions about whether elephants can undergo multiple infections with EEHVs have not been addressed previously. Real-time quantitative polymerase chain reaction was used to determine the kinetics of EEHV1 loads, and genotypic analysis was performed on EEHV1 DNA detected in various fluid samples obtained from five Asian elephants that survived detectable EEHV1 DNAemia on at least two separate occasions. In three elephants displaying clinical signs of illness, preclinical EEHV1 DNAemia was detectable, and peak whole-blood viral loads occurred 3–8 days after the onset of clinical signs. In two elephants with EEHV1 DNAemia that persisted for 7–21 days, no clinical signs of illness were observed. Detection of EEHV1 DNA in trunk washes peaked approximately 21 days after DNAemia, and viral genotypes detected during DNAemia matched those detected in subsequent trunk washes from the same elephant. In each of the five elephants, two distinct EEHV1 genotypes were identified in whole blood and trunk washes at different time points. In each case, these genotypes represented both an EEHV1A and an EEHV1B subtype. These data suggest that knowledge of viral loads could be useful for the management of elephants before or during clinical illness. Furthermore, sequential infection with both EEHV1 subtypes occurs in Asian elephants, suggesting that they do not elicit cross-protective sterilizing immunity. These data will be useful to individuals involved in the husbandry and clinical care of Asian elephants. PMID:23505702
Traditional Banana Diversity in Oceania: An Endangered Heritage
Kagy, Valérie; Wong, Maurice; Vandenbroucke, Henri; Jenny, Christophe; Dubois, Cécile; Ollivier, Anthony; Cardi, Céline; Mournet, Pierre; Tuia, Valérie; Roux, Nicolas; Doležel, Jaroslav; Perrier, Xavier
2016-01-01
This study aims to understand the genetic diversity of traditional Oceanian starchy bananas in order to propose an efficient conservation strategy for these endangered varieties. SSR and DArT molecular markers are used to characterize a large sample of Pacific accessions, from New Guinea to Tahiti and Hawaii. All Pacific starchy bananas are shown of New Guinea origin, by interspecific hybridization between Musa acuminata (AA genome), more precisely its local subspecies M. acuminata ssp. banksii, and M. balbisiana (BB genome) generating triploid AAB Pacific starchy bananas. These AAB genotypes do not form a subgroup sensu stricto and genetic markers differentiate two subgroups across the three morphotypes usually identified: Iholena versus Popoulu and Maoli. The Popoulu/Maoli accessions, even if morphologically diverse throughout the Pacific, cluster in the same genetic subgroup. However, the subgroup is not strictly monophyletic and several close, but different genotypes are linked to the dominant genotype. One of the related genotypes is specific to New Caledonia (NC), with morphotypes close to Maoli, but with some primitive characters. It is concluded that the diffusion of Pacific starchy AAB bananas results from a series of introductions of triploids originating in New Guinea area from several sexual recombination events implying different genotypes of M. acuminata ssp. banksii. This scheme of multiple waves from the New Guinea zone is consistent with the archaeological data for peopling of the Pacific. The present geographic distribution suggests that a greater diversity must have existed in the past. Its erosion finds parallels with the erosion of cultural traditions, inexorably declining in most of the Polynesian or Melanesian Islands. Symmetrically, diversity hot spots appear linked to the local persistence of traditions: Maoli in New Caledonian Kanak traditions or Iholena in a few Polynesian islands. These results will contribute to optimizing the conservation strategy for the ex-situ Pacific Banana Collection supported collectively by the Pacific countries. PMID:26982801
Hu, H; Harmer, C; Anuj, S; Wainwright, C E; Manos, J; Cheney, J; Harbour, C; Zablotska, I; Turnbull, L; Whitchurch, C B; Grimwood, K; Rose, B
2013-03-01
Studies of the type 3 secretion system (T3SS) in Pseudomonas aeruginosa isolates from chronically infected older children and adults with cystic fibrosis (CF) show a predominantly exoS+/exoU- (exoS+) genotype and loss of T3SS effector secretion over time. Relatively little is known about the role of the T3SS in the pathogenesis of early P. aeruginosa infection in the CF airway. In this longitudinal study, 168 P. aeruginosa isolates from 58 children diagnosed with CF following newborn screening and 47 isolates from homes of families with or without children with CF were genotyped by pulsed-field gel electrophoresis (PFGE) and T3SS genotype and phenotype determined using multiplex PCR and western blotting. Associations were sought between T3SS data and clinical variables and comparisons made between T3SS data of clinical and environmental PFGE genotypes. Seventy-seven of the 92 clinical strains were exoS+ (71% secretors (ExoS+)) and 15 were exoU+ (93% secretors (ExoU+)). Initial exoS+ strains were five times more likely to secrete ExoS than subsequent exoS+ strains at first isolation. The proportion of ExoS+ strains declined with increasing age at acquisition. No associations were found between T3SS characteristics and gender, site of isolation, exacerbation, a persistent strain or pulmonary outcomes. Fourteen of the 23 environmental strains were exoS+ (79% ExoS+) and nine were exoU+ (33% ExoU+). The exoU+ environmental strains were significantly less likely to secrete ExoU than clinical strains. This study provides new insight into the T3SS characteristics of P. aeruginosa isolated from the CF airway early in life. © 2012 The Authors. Clinical Microbiology and Infection © 2012 European Society of Clinical Microbiology and Infectious Diseases.
Traditional Banana Diversity in Oceania: An Endangered Heritage.
Kagy, Valérie; Wong, Maurice; Vandenbroucke, Henri; Jenny, Christophe; Dubois, Cécile; Ollivier, Anthony; Cardi, Céline; Mournet, Pierre; Tuia, Valérie; Roux, Nicolas; Doležel, Jaroslav; Perrier, Xavier
2016-01-01
This study aims to understand the genetic diversity of traditional Oceanian starchy bananas in order to propose an efficient conservation strategy for these endangered varieties. SSR and DArT molecular markers are used to characterize a large sample of Pacific accessions, from New Guinea to Tahiti and Hawaii. All Pacific starchy bananas are shown of New Guinea origin, by interspecific hybridization between Musa acuminata (AA genome), more precisely its local subspecies M. acuminata ssp. banksii, and M. balbisiana (BB genome) generating triploid AAB Pacific starchy bananas. These AAB genotypes do not form a subgroup sensu stricto and genetic markers differentiate two subgroups across the three morphotypes usually identified: Iholena versus Popoulu and Maoli. The Popoulu/Maoli accessions, even if morphologically diverse throughout the Pacific, cluster in the same genetic subgroup. However, the subgroup is not strictly monophyletic and several close, but different genotypes are linked to the dominant genotype. One of the related genotypes is specific to New Caledonia (NC), with morphotypes close to Maoli, but with some primitive characters. It is concluded that the diffusion of Pacific starchy AAB bananas results from a series of introductions of triploids originating in New Guinea area from several sexual recombination events implying different genotypes of M. acuminata ssp. banksii. This scheme of multiple waves from the New Guinea zone is consistent with the archaeological data for peopling of the Pacific. The present geographic distribution suggests that a greater diversity must have existed in the past. Its erosion finds parallels with the erosion of cultural traditions, inexorably declining in most of the Polynesian or Melanesian Islands. Symmetrically, diversity hot spots appear linked to the local persistence of traditions: Maoli in New Caledonian Kanak traditions or Iholena in a few Polynesian islands. These results will contribute to optimizing the conservation strategy for the ex-situ Pacific Banana Collection supported collectively by the Pacific countries.
From Treating Childhood Malnutrition to Public Health Nutrition.
James, W Philip T
2018-01-01
This analysis sets out an overview of an IUNS presentation of a European clinician's assessment of the challenges of coping with immediate critical clinical problems and how to use metabolic and a mechanistic understanding of disease when developing nutritional policies. Critically ill malnourished children prove very sensitive to both mineral and general nutritional overload, but after careful metabolic control they can cope with a high-quality, energy-rich diet provided their initial lactase deficiency and intestinal atrophy are taken into account. Detailed intestinal perfusion studies also showed that gastroenteritis can be combatted by multiple frequent glucose/saline feeds, which has saved millions of lives. However, persisting pancreatic islet cell damage may explain our findings of pandemic rates of adult diabetes in Asia, the Middle East and Mexico and perhaps elsewhere including Africa and Latin America. These handicaps together with the magnitude of epigenetic changes emphasized the importance of a whole life course approach to nutritional policy making. Whole body calorimetric analyses of energy requirements allowed a complete revision of estimates for world food needs and detailed clinical experience showed the value of redefining stunting and wasting in childhood and the value of BMI for classifying appropriate adult weights, underweight and obesity. Lithium tracer studies of dietary salt sources should also dictate priorities in population salt-reduction strategies. Metabolic and clinical studies combined with meticulous measures of population dietary intakes now suggest the need for far more radical steps to lower the dietary goals for both free sugars and total dietary fat unencumbered by flawed cohort studies that neglect not only dietary errors but also the intrinsic inter-individual differences in metabolic responses to most nutrients. Key Messages: Detailed clinical and metabolic analyses of physiological responses combined with rigorous dietary and preferably biomarker of mechanistic pathways should underpin a new approach not only to clinical care but also to the development of more radical nutritional policies. © 2018 S. Karger AG, Basel.
Enhancing the Teaching of Evolution in Public Health.
Omenn, Gilbert S
2011-12-01
Public health courses are emerging as popular undergraduate offerings, especially at universities with schools of public health. It is important to note that evolution has shaped the burden of disease in the modern world in which we practice and educate for public health. Human cultures and technologies have modified life on Planet Earth and have co-evolved with myriad other species, including microorganisms, plant and animal sources of food, invertebrate vectors of disease, and intermediate bird, mammal, and primate hosts. Molecular mechanisms of evolution have produced differential resistance or susceptibility to infectious agents, including malaria, plague, smallpox, TB, measles, and diarrheal and respiratory diseases. The domestication of sheep and cattle led to natural selection in favor of human populations able to digest milk throughout life through persistence into adulthood of lactase enzyme expression in the intestine, a major story of anthropology. The emergence of a "Western diet" of dairy, refined cereal grains, refined sugars, vegetable oils, alcoholic beverages, salt, and omega-6-rich meats has dramatically altered glycemic load, fatty acid composition, macro-nutrients, acid-base balance, sodium/potassium ratio, and fiber content. This is a major story of nutrition and disease. The results include epidemics of atherosclerotic cardiovascular disease, obesity, diabetes, high blood pressure, osteoporosis, certain cancers, and bowel, inflammatory, and autoimmune disorders. Another interesting phenomenon is the selection of excessive hemostatic activity from platelets and the plasma clotting proteins; what was protective against death from bleeding after injuries among hunter-gatherers or from pregnancy-related hemorrhage now contributes to thrombosis underlying heart attacks and strokes. Conversely, there is little pressure against hemostasis and thrombosis since deaths from these causes occur mostly after the reproductive years of life. Learning about evolution over millennia for humans and over hours or days for microbes enlivens the experience of understanding evolutionary biology in public health context.
Bassi, Clément; Taha, Muhamed-Kheir; Merle, Christian; Hong, Eva; Lévy-Bruhl, Daniel; Barret, Anne-Sophie; Mounchetrou Njoya, Ibrahim
2017-01-01
Between February and May 2017, two cases of invasive meningococcal disease caused by a new, rapidly expanding serogroup W meningococci variant were reported among students of an international university in Paris. Bacteriological investigations showed that isolates shared identical genotypic formula (W:P1.5,2:F1–1:cc11) and belonged to the South American/UK lineage. A vaccination campaign was organised that aimed at preventing new cases linked to potential persistence of the circulation of the bacteria in the students. PMID:28749333
How will HPV vaccines affect cervical cancer?
Roden, Richard; Wu, T.-C.
2011-01-01
Cancer of the uterine cervix is the second largest cause of cancer deaths in women, and its toll is greatest in populations that lack screening programmes to detect precursor lesions. Persistent infection with ‘high risk’ genotypes of human papillomavirus (HPV) is necessary, although not sufficient, to cause cervical carcinoma. Therefore, HPV vaccination provides an opportunity to profoundly affect cervical cancer incidence worldwide. A recently licensed HPV subunit vaccine protects women from a high proportion of precursor lesions of cervical carcinoma and most genital warts. Here we examine the ramifications and remaining questions that surround preventive HPV vaccines. PMID:16990853
Pérez-Bravo, F; Fuentes, M; Angel, B; Sanchez, H; Carrasco, E; Santos, J L; Lera, L; Albala, C
2006-12-01
The aim of this study was to assess the frequency of fatty acid binding protein 2 (FABP2) Ala54Thr genetic polymorphism and to evaluate its association with obesity and insulin resistance in Chilean aboriginal populations. A sample of 96 urban Aymara and 111 urban Mapuche subjects aged 20-80 years were recruited for this cross-sectional study. Glucose, insulin and lipid profile were measured in fasting plasma samples. Insulin resistance was estimated through the HOMA-IR model. FABP2 Ala54Thr genotypes were determined by PCR followed by RFLP analysis. The allele frequency of Thr54 variant was estimated as 18.2% in Aymara subjects, which is one of the lowest reported to date. The corresponding frequency in Mapuche subjects was 31.9% (p<0.002). Regarding genotype-phenotype associations, no significant differences were found in any of the anthropometric or metabolic variables according to Ala54Thr genotypes. After adjustment by BMI and metabolic variables through a logistic regression analysis, the association of the FABP2 polymorphism with ethnic group persisted (Mapuche group: OR=2.37, 95% CI 1.319-4.277, p=0.004) It is unlikely that Ala54Thr polymorphism of the FABP2 gene plays a relevant role in obesity and insulin resistance in Chilean ethnic groups.
Experimental infection of dogs with Bartonella henselae and Bartonella vinsonii subsp. berkhoffii.
Balakrishnan, Nandhakumar; Cherry, Natalie A; Linder, Keith E; Pierce, Eric; Sontakke, Neal; Hegarty, Barbara C; Bradley, Julie M; Maggi, Ricardo G; Breitschwerdt, Edward B
2013-11-15
The lack of a suitable infection model remains an important obstacle for the pathophysiological understanding of Bartonella spp. The following pilot study was designed to determine whether cell culture-grown Bartonella henselae SA2 and Bartonella vinsonii subsp. berkhoffii genotype III would cause persistent bacteremia in dogs. Pre-inoculation screening established that two laboratory-raised Golden retrievers were naturally-infected with Bartonella koehlerae. Despite prior infection, one dog each was inoculated subcutaneously with 5 × 10(4)B. henselae (SA2 strain) or 3 × 10(4)B. vinsonii subsp. berkhoffii genotype III. Dogs were bled weekly for serological testing and culture using Bartonella alpha proteobacteria growth medium (BAPGM) diagnostic platform. Dog 1 seroconverted to B. henselae and Dog 2 seroconverted to B. vinsonii subsp. berkhoffii genotype III. Throughout the study period, Bartonella spp. DNA was neither amplified nor isolated in ante-mortem BAPGM enrichment blood cultures. B. henselae SA2 was isolated from a postmortem bone marrow from Dog 1 and B. koehlerae DNA was amplified from postmortem lung from Dog 2 following BAPGM enrichment culture. Limitations include lack of uninfected controls, a potentially suboptimal B. vinsonii subsp. berkhoffii inoculum and a relatively short duration of study. We conclude that following intradermal infection, sequestration of Bartonella spp. in tissues may limit diagnostic detection of these bacteria in dog blood samples. Copyright © 2013 Elsevier B.V. All rights reserved.
Asmundsson, Ingrid M; Dubey, J P; Rosenthal, Benjamin M
2006-09-01
The population genetics and systematics of most coccidians remain poorly defined despite their impact on human and veterinary health. Non-recombinant parasite clones characterized by distinct transmission and pathogenesis traits persist in the coccidian Toxoplasma gondii despite opportunities for sexual recombination. In order to determine whether this may be generally true for tissue-cyst forming coccidia, and to address evolutionary and taxonomic problems within the genus Sarcocystis, we characterized polymorphic microsatellite markers in Sarcocystis neurona, the major causative agent of equine protozoal myeloencephalitis (EPM). Bayesian statistical modeling, phylogenetic reconstruction based on genotypic chord distances, and analyses of linkage disequilibrium were employed to examine the population structure within S. neurona and closely related Sarcocystis falcatula isolates from North and South America. North American S. neurona were clearly differentiated from those of South America and also from isolates of S. falcatula. Although S. neurona is characterized by substantial allelic and genotypic diversity typical of interbreeding populations, one genotype occurs with significantly excessive frequency; thus, some degree of asexual propagation of S. neurona clones may naturally occur. Finally, S. neurona isolated from disparate North American localities and diverse hosts (opossums, a Southern sea otter, and horses) comprise a single genetic population. Isolates associated with clinical neurological disease bear no obvious distinction as measured by these presumably neutral genetic markers.
Ruiz, Antonio; Foronda, Pilar; González, Jorge F; Guedes, Aránzazu; Abreu-Acosta, Néstor; Molina, José M; Valladares, Basilio
2008-06-14
Giardia duodenalis (syn. Giardia lamblia, Giardia intestinalis) is a wide-spread intestinal protozoa of both humans and animals. Although giardiosis in goat is commonly asymptomatic, young kids may bear an enteric disease associated with persistent diarrhoea and delayed weight gain. In the present study we have analysed the occurrence of Giardia in 315 young goat kids (2-6 months old) from Gran Canaria Island (Spain) through visualization of faecal cysts. The identification of genotypes of G. duodenalis among the farms was attained by nested PCR of the triophosphate isomerase (TPI) and single PCR of beta-giardin genes and subsequent sequencing. Positive samples were found in 42.2% of the animals and 95.5% of the farms. Goat faecal specimens were positive for only livestock-associated G. duodenalis assemblage E genotype for both TPI and beta-giardin genes. The genetic analysis of these two loci revealed the presence of different haplotypes among the farms included in the survey and high homology with homologous genes from cattle and sheep. Altogether, the data presented here provide additional information to the prevalence and genetic characterization of Giardia isolates. The absence of assemblages A and B in this study suggests that zoonotic transmission of Giardia from goats could be of low epidemiological significance, although these findings should be validated in studies including other geographical areas, age groups and larger number of samples.
di Rienzo, Valentina; Bubici, Giovanni; Montemurro, Cinzia; Cillo, Fabrizio
2018-01-01
In tomato, resistance to Tomato spotted wilt virus (TSWV) is conferred by the dominant gene, designated Sw-5. Virulent Sw-5 resistance breaking (SRB) mutants of TSWV have been reported on Sw-5 tomato cultivars. Two different PCR-based allelic discrimination techniques, namely Custom TaqMan™ SNP Genotyping and high-resolution melting (HRM) assays, were developed and compared for their ability to distinguish between avirulent (Sw-5 non-infecting, SNI) and SRB biotypes. TaqMan assays proved to be more sensitive (threshold of detection in a range of 50-70 TSWV RNA copies) and more reliable than HRM, assigning 25 TSWV isolates to their correct genotype with an accuracy of 100%. Moreover, the TaqMan SNP assays were further improved developing a rapid and simple protocol that included crude leaf extraction for RNA template preparations. On the other hand, HRM assays showed higher levels of sensitivity than TaqMan when used to co-detect both biotypes in different artificial mixtures. These diagnostic assays contributed to gain preliminary information on the epidemiology of TSWV isolates in open field conditions. In fact, the presented data suggest that SRB isolates are present as stable populations established year round, persisting on both winter (globe artichoke) and summer (tomato) crops, in the same cultivated areas of Southern Italy.
Resistance to thermal stress in corals without changes in symbiont composition.
Bellantuono, Anthony J; Hoegh-Guldberg, Ove; Rodriguez-Lanetty, Mauricio
2012-03-22
Discovering how corals can adjust their thermal sensitivity in the context of global climate change is important in understanding the long-term persistence of coral reefs. In this study, we showed that short-term preconditioning to higher temperatures, 3°C below the experimentally determined bleaching threshold, for a period of 10 days provides thermal tolerance for the symbiosis stability between the scleractinian coral, Acropora millepora and Symbiodinium. Based on genotypic analysis, our results indicate that the acclimatization of this coral species to thermal stress does not come down to simple changes in Symbiodinium and/or the bacterial communities that associate with reef-building corals. This suggests that the physiological plasticity of the host and/or symbiotic components appears to play an important role in responding to ocean warming. The further study of host and symbiont physiology, both of Symbiodinium and prokaryotes, is of paramount importance in the context of global climate change, as mechanisms for rapid holobiont acclimatization will become increasingly important to the long-standing persistence of coral reefs.
Nyitray, Alan G.; Carvalho da Silva, Roberto J.; Chang, Mihyun; Baggio, Maria Luiza; Ingles, Donna J.; Abrahamsen, Martha; Papenfuss, Mary; Lin, Hui-Yi; Salmerón, Jorge; Quiterio, Manuel; Lazcano-Ponce, Eduardo; Villa, Luisa L.; Giuliano, Anna R.
2016-01-01
Background. Given high rates of anal disease, we investigated the natural history of high-risk anal human papillomavirus (HPV) among a multinational group of men who have sex with men (MSM) aged 18–64 years. Methods. Anal specimens from human immunodeficiency virus–negative men from Brazil, Mexico, and the United States were genotyped. Over 2 years, 406 MSM provided evaluable specimens every 6 months for ≥2 visits. These men were stratified into men who have sex only with men (MSOM, n = 70) and men who have sex with women and men (MSWM, n = 336). Persistence was defined as ≥12 months’ type-specific duration and could begin with either a prevalent or incident infection. Prevalence ratios and 95% confidence intervals were calculated by Poisson regression. Results. Median follow-up time was 2.1 years. Retention was 82%. Annual cumulative incidence of 9-valent vaccine types was 19% and 8% among MSOM and MSWM, respectively (log-rank P = .02). Duration of anal HPV did not differ for MSOM and MSWM and was a median of 6.9 months for HPV-16 after combining men from the 2 groups. Among men with prevalent high-risk infection (n = 106), a total of 36.8%, retained the infection for at least 24 months. For those with prevalent HPV-16 (n = 27), 29.6% were persistent for at least 24 months. Persistence of high-risk HPV was associated with number of male anal sex partners and inversely associated with number of female sex partners. Conclusions. MSM with prevalent high-risk HPV infection should be considered at increased risk for nontransient infection. PMID:26962079
Linnstaedt, Sarah D; Hu, JunMei; Bortsov, Andrey V; Soward, April C; Swor, Robert; Jones, Jeffrey; Lee, David; Peak, David; Domeier, Robert; Rathlev, Niels; Hendry, Phyllis; McLean, Samuel A
2015-07-01
The μ-opioid receptor 1 (OPRM1) binds endogenous opioids. Increasing evidence suggests that endogenous OPRM1 agonists released at the time of trauma may contribute to the development of posttraumatic musculoskeletal pain (MSP). In this prospective observational study, we evaluated the hypothesis that individuals with an AG or GG genotype at the OPRM1 A118 G allele, which results in a reduced response to opioids, would have less severe MSP 6 weeks after motor vehicle collision (MVC). Based on previous evidence, we hypothesized that this effect would be sex-dependent and most pronounced among women with substantial peritraumatic distress. European American men and women ≥ 18 years of age presenting to the emergency department after MVC and discharged to home after evaluation (N = 948) were enrolled. Assessments included genotyping and 6-week evaluation of overall MSP severity (0-10 numeric rating scale). In linear regression modeling, a significant A118 G Allele × Sex interaction was observed: an AG/GG genotype predicted reduced MSP severity among women with substantial peritraumatic distress (β = -.925, P = .014) but not among all women. In contrast, men with an AG/GG genotype experienced increased MSP severity at 6 weeks (β = .827, P = .019). Further studies are needed to understand the biologic mechanisms mediating observed sex differences in A118 G effects. These results suggest a sex-dependent mechanism by which an emotional response to trauma (distress) contributes to a biologic mechanism (endogenous opioid release) that increases MSP in the weeks after stress exposure. These results also support the hypothesis that endogenous opioids influence pain outcomes differently in men and women. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.
Barman, Subrata; Marinova-Petkova, Atanaska; Hasan, M Kamrul; Akhtar, Sharmin; El-Shesheny, Rabeh; Turner, Jasmine CM; Franks, John; Walker, David; Seiler, Jon; Friedman, Kimberly; Kercher, Lisa; Jeevan, Trushar; Darnell, Daniel; Kayali, Ghazi; Jones-Engel, Lisa; McKenzie, Pamela; Krauss, Scott; Webby, Richard J; Webster, Robert G; Feeroz, Mohammed M
2017-01-01
Highly pathogenic avian influenza H5N1 viruses were first isolated in Bangladesh in February 2007. Subsequently, clades 2.2.2, 2.3.4.2 and 2.3.2.1a were identified in Bangladesh, and our previous surveillance data revealed that by the end of 2014, the circulating viruses exclusively comprised clade 2.3.2.1a. We recently determined the status of circulating avian influenza viruses in Bangladesh by conducting surveillance of live poultry markets and waterfowl in wetland areas from February 2015 through February 2016. Until April 2015, clade 2.3.2.1a persisted without any change in genotype. However, in June 2015, we identified a new genotype of H5N1 viruses, clade 2.3.2.1a, which quickly became predominant. These newly emerged H5N1 viruses contained the hemagglutinin, neuraminidase and matrix genes of circulating 2.3.2.1a Bangladeshi H5N1 viruses and five other genes of low pathogenic Eurasian-lineage avian influenza A viruses. Some of these internal genes were closely related to those of low pathogenic viruses isolated from ducks in free-range farms and wild birds in a wetland region of northeastern Bangladesh, where commercially raised domestic ducks have frequent contact with migratory birds. These findings indicate that migratory birds of the Central Asian flyway and domestic ducks in the free-range farms in Tanguar haor-like wetlands played an important role in the emergence of this novel genotype of highly pathogenic H5N1 viruses. PMID:28790460
Interacting Microbe and Litter Quality Controls on Litter Decomposition: A Modeling Analysis
Moorhead, Daryl; Lashermes, Gwenaëlle; Recous, Sylvie; Bertrand, Isabelle
2014-01-01
The decomposition of plant litter in soil is a dynamic process during which substrate chemistry and microbial controls interact. We more clearly quantify these controls with a revised version of the Guild-based Decomposition Model (GDM) in which we used a reverse Michaelis-Menten approach to simulate short-term (112 days) decomposition of roots from four genotypes of Zea mays that differed primarily in lignin chemistry. A co-metabolic relationship between the degradation of lignin and holocellulose (cellulose+hemicellulose) fractions of litter showed that the reduction in decay rate with increasing lignin concentration (LCI) was related to the level of arabinan substitutions in arabinoxylan chains (i.e., arabinan to xylan or A∶X ratio) and the extent to which hemicellulose chains are cross-linked with lignin in plant cell walls. This pattern was consistent between genotypes and during progressive decomposition within each genotype. Moreover, decay rates were controlled by these cross-linkages from the start of decomposition. We also discovered it necessary to divide the Van Soest soluble (labile) fraction of litter C into two pools: one that rapidly decomposed and a second that was more persistent. Simulated microbial production was consistent with recent studies suggesting that more rapidly decomposing materials can generate greater amounts of potentially recalcitrant microbial products despite the rapid loss of litter mass. Sensitivity analyses failed to identify any model parameter that consistently explained a large proportion of model variation, suggesting that feedback controls between litter quality and microbial activity in the reverse Michaelis-Menten approach resulted in stable model behavior. Model extrapolations to an independent set of data, derived from the decomposition of 12 different genotypes of maize roots, averaged within <3% of observed respiration rates and total CO2 efflux over 112 days. PMID:25264895
Artursson, Karin; Söderlund, Robert; Liu, Lihong; Monecke, Stefan; Schelin, Jenny
2016-09-25
Reducing the prevalence of mastitis caused by Staphylococcus aureus (S. aureus) is essential to improve animal health and reduce economic losses for farmers. The clinical outcome of acute mastitis and risk of progression to persistent mastitis can, at least to some extent, be related to genetic variants of the strain causing the infection. In the present study we have used microarrays to investigate the presence of virulence genes in S. aureus isolates from dairy cows with acute clinical mastitis (n=70) and correlated the findings to other genotypic and phenotypic characteristics. Among the most commonly found virulence factors were genes encoding several hemolysin types, leukocidins D and lukM/lukF-P83, clumping factors A and B, fibrinogen binding protein and fibronectin-binding protein A. Some virulence factors e.g. fibronectin-binding protein B and Staphylococcus aureus surface protein G were less common. Genes coding for several staphylococcal enterotoxins and toxic shock syndrome toxin-1 (TSST-1) were commonly found, especially in one major pulsotype. No beta-lactamase genes were found in any common pulsotype, while present in some rare pulsotypes, indicated to be of human origin. Production of TSST-1, enterotoxins, hemolysins and beta-lactamase could all be positively correlated to presence of the corresponding genes. This study reveals a number of genotypic differences and similarities among common and rare pulsotypes of S. aureus from cases of mastitis in Sweden. The results could help the design of diagnostic tools to guide on-farm interventions according to the expected impact on udder health from a specific S. aureus genotype. Copyright © 2016 Elsevier B.V. All rights reserved.
Volaire, F; Norton, M R; Norton, G M; Lelièvre, F
2005-05-01
Summer dormancy in perennial grasses has been studied inadequately, despite its potential to enhance plant survival and persistence in Mediterranean areas. The aim of the present work was to characterize summer dormancy and dehydration tolerance in two cultivars of Dactylis glomerata (dormant 'Kasbah', non-dormant 'Oasis') and their hybrid using physiological indicators associated with these traits. Dehydration tolerance was assessed in a glasshouse experiment, while seasonal metabolic changes which produce putative protectants for drought, such as carbohydrates and dehydrins that might be associated with summer dormancy, were analysed in the field. The genotypes differed in their ability to survive increasing soil water deficit: lethal soil water potential (Psi(s)) was -3.4 MPa for 'Kasbah' (although non-dormant), -1.3 MPa for 'Oasis', and -1.6 MPa for their hybrid. In contrast, lethal water content of apices was similar for all genotypes (approx. 0.45 g H(2)O g d. wt(-1)), and hence the greater survival of 'Kasbah' can be ascribed to better drought avoidance rather than dehydration tolerance. In autumn-sown plants, 'Kasbah' had greatest dormancy, the hybrid was intermediate and 'Oasis' had none. The more dormant the genotype, the lower the metabolic activity during summer, and the earlier the activity declined in spring. Decreased monosaccharide content was an early indicator of dormancy induction. Accumulation of dehydrins did not correlate with stress tolerance, but dehydrin content was a function of the water status of the tissues, irrespective of the soil moisture. A protein of approx. 55 kDa occurred in leaf bases of the most dormant cultivar even in winter. Drought avoidance and summer dormancy are correlated but can be independently expressed. These traits are heritable, allowing selection in breeding programmes.
Dudley, Matthew Z.; Sheen, Patricia; Gilman, Robert H.; Ticona, Eduardo; Friedland, Jon S.; Kirwan, Daniela E.; Caviedes, Luz; Rodriguez, Richard; Cabrera, Lilia Z.; Coronel, Jorge; Grandjean, Louis; Moore, David A. J.; Evans, Carlton A.; Huaroto, Luz; Chávez-Pérez, Víctor; Zimic, Mirko
2016-01-01
Hospital infection control measures are crucial to tuberculosis (TB) control strategies within settings caring for human immunodeficiency virus (HIV)–positive patients, as these patients are at heightened risk of developing TB. Pyrazinamide (PZA) is a potent drug that effectively sterilizes persistent Mycobacterium tuberculosis bacilli. However, PZA resistance associated with mutations in the nicotinamidase/pyrazinamidase coding gene, pncA, is increasing. A total of 794 patient isolates obtained from four sites in Lima, Peru, underwent spoligotyping and drug resistance testing. In one of these sites, the HIV unit of Hospital Dos de Mayo (HDM), an isolation ward for HIV/TB coinfected patients opened during the study as an infection control intervention: circulating genotypes and drug resistance pre- and postintervention were compared. All other sites cared for HIV-negative outpatients: genotypes and drug resistance rates from these sites were compared with those from HDM. HDM patients showed high concordance between multidrug resistance, PZA resistance according to the Wayne method, the two most common genotypes (spoligotype international type [SIT] 42 of the Latino American-Mediterranean (LAM)-9 clade and SIT 53 of the T1 clade), and the two most common pncA mutations (G145A and A403C). These associations were absent among community isolates. The infection control intervention was associated with 58–92% reductions in TB caused by SIT 42 or SIT 53 genotypes (odds ratio [OR] = 0.420, P = 0.003); multidrug-resistant TB (OR = 0.349, P < 0.001); and PZA-resistant TB (OR = 0.076, P < 0.001). In conclusion, pncA mutation typing, with resistance testing and spoligotyping, was useful in identifying a nosocomial TB outbreak and demonstrating its resolution after implementation of infection control measures. PMID:27928075
Revisiting Robustness and Evolvability: Evolution in Weighted Genotype Spaces
Partha, Raghavendran; Raman, Karthik
2014-01-01
Robustness and evolvability are highly intertwined properties of biological systems. The relationship between these properties determines how biological systems are able to withstand mutations and show variation in response to them. Computational studies have explored the relationship between these two properties using neutral networks of RNA sequences (genotype) and their secondary structures (phenotype) as a model system. However, these studies have assumed every mutation to a sequence to be equally likely; the differences in the likelihood of the occurrence of various mutations, and the consequence of probabilistic nature of the mutations in such a system have previously been ignored. Associating probabilities to mutations essentially results in the weighting of genotype space. We here perform a comparative analysis of weighted and unweighted neutral networks of RNA sequences, and subsequently explore the relationship between robustness and evolvability. We show that assuming an equal likelihood for all mutations (as in an unweighted network), underestimates robustness and overestimates evolvability of a system. In spite of discarding this assumption, we observe that a negative correlation between sequence (genotype) robustness and sequence evolvability persists, and also that structure (phenotype) robustness promotes structure evolvability, as observed in earlier studies using unweighted networks. We also study the effects of base composition bias on robustness and evolvability. Particularly, we explore the association between robustness and evolvability in a sequence space that is AU-rich – sequences with an AU content of 80% or higher, compared to a normal (unbiased) sequence space. We find that evolvability of both sequences and structures in an AU-rich space is lesser compared to the normal space, and robustness higher. We also observe that AU-rich populations evolving on neutral networks of phenotypes, can access less phenotypic variation compared to normal populations evolving on neutral networks. PMID:25390641
Genetic and Environmental Determinants of Otitis Media in an Indigenous Filipino Population.
Santos-Cortez, Regie Lyn P; Reyes-Quintos, Ma Rina T; Tantoco, Ma Leah C; Abbe, Izoduwa; Llanes, Erasmo Gonzalo D V; Ajami, Nadim J; Hutchinson, Diane S; Petrosino, Joseph F; Padilla, Carmencita D; Villarta, Romeo L; Gloria-Cruz, Teresa Luisa; Chan, Abner L; Cutiongco-de la Paz, Eva Maria; Chiong, Charlotte M; Leal, Suzanne M; Abes, Generoso T
2016-11-01
To identify genetic and environmental risk factors for otitis media in an indigenous Filipino population. Cross-sectional study. Indigenous Filipino community. Clinical history and information on breastfeeding, tobacco smoke exposure, and swimming were obtained from community members. Heads of households were interviewed for family history and personal beliefs on ear health. Height and weight were measured. Otoscopic findings were described for the presence and character of perforation or discharge. An A2ML1 duplication variant that confers otitis media susceptibility was Sanger sequenced in all DNA samples. Co-occurrence of middle ear bacteria detected by 16S rRNA gene sequencing was determined according to A2ML1 genotype and social cluster. The indigenous Filipino population has a ~50% prevalence of otitis media. Young age was associated with otitis media (4 age strata; P = .004); however, age was nonsignificant as a bistratal or continuous variable. There was no association between otitis media and sex, body mass index, breastfeeding, tobacco exposure, or deep swimming. In multivariate analyses, A2ML1 genotype is the strongest predictor of otitis media, with an odds ratio of 3.7 (95% confidence interval: 1.3-10.8; P = .005). When otitis media diagnoses were plotted across ages, otitis media was observed within the first year of life, and chronic otitis media persisted up to adulthood, particularly in A2ML1-variant carriers. Among indigenous Filipinos, A2ML1 genotype is the primary risk factor for otitis media and main determinant of disease progression, although age, the middle ear microbiome, and social clusters might modulate the effect of the A2ML1 genotype. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.
Genetic and Environmental Determinants of Otitis Media in an Indigenous Filipino Population
Santos-Cortez, Regie Lyn P.; Reyes-Quintos, Ma. Rina T.; Tantoco, Ma. Leah C.; Abbe, Izoduwa; Llanes, Erasmo Gonzalo d.V.; Ajami, Nadim J.; Hutchinson, Diane S.; Petrosino, Joseph F.; Padilla, Carmencita D.; Villarta, Romeo L.; Gloria-Cruz, Teresa Luisa; Chan, Abner L.; Cutiongco-de la Paz, Eva Maria; Chiong, Charlotte M.; Leal, Suzanne M.; Abes, Generoso T.
2016-01-01
Objective To identify genetic and environmental risk factors for otitis media in an indigenous Filipino population Study Design Cross-sectional study Setting Indigenous Filipino community Subjects and Methods Clinical history and information on breastfeeding, tobacco smoke exposure and swimming were obtained from community members. Heads of households were interviewed for family history and personal beliefs on ear health. Height and weight were measured. Otoscopic findings were described for presence and character of perforation or discharge. An A2ML1 duplication variant that confers otitis media susceptibility was Sanger-sequenced in all DNA samples. Co-occurrence of middle ear bacteria detected by 16S rRNA gene sequencing was determined according to A2ML1 genotype and social cluster. Results The indigenous Filipino population has a ~50% prevalence of otitis media. Young age was associated with otitis media (4 age strata; p=0.004), however age was non-significant as a bi-stratal or continuous variable. There was no association between otitis media and gender, body mass index, breastfeeding, tobacco exposure or deep swimming. In multivariate analyses, A2ML1 genotype is the strongest predictor of otitis media, with an odds ratio of 3.7 (95%CI: 1.3, 10.8; p=0.005). When otitis media diagnoses were plotted across ages, otitis media was observed within the first year of life and chronic otitis media persisted up to adulthood, particularly in A2ML1 variant carriers. Conclusion Among indigenous Filipinos, A2ML1 genotype is the primary risk factor for otitis media and main determinant of disease progression, although age, the middle ear microbiome and social clusters might modulate the effect of the A2ML1 genotype. PMID:27484237
Dill, Alisa; Letra, Ariadne; de Souza, Letıcia Chaves; Yadlapati, Mamatha; Biguetti, Claudia Cristina; Garlet, Gustavo Pompermaier; Vieira, Alexandre R.; Silva, Renato Menezes
2017-01-01
Introduction It has been proposed that individual genetic predisposition may contribute to persistent apical periodontitis. Cytokines are associated with levels of inflammation and are involved in caries, pulpal, and periapical tissue destruction. We hypothesized that polymorphisms in cytokine genes may contribute to an individual’s increased susceptibility to apical tissue destruction in response to deep carious lesions. Methods Subjects with deep carious lesions, with or without periapical lesions (≥ 3 mm) were recruited at the University of Pittsburgh and the University of Texas at Houston. Genomic DNA samples of 316 patients were sorted into 2 groups: 136 cases with deep carious lesions and periapical lesions (cases), and 180 cases with deep carious lesions but no periapical lesions (controls). Nine single nucleotide polymorphisms in IL1B, IL6, TNF, RANK, RANKL and OPG genes were selected for genotyping. Genotypes were generated by endpoint analysis using Taqman chemistry in a real-time polymerase chain reaction instrument. Allele and genotype frequencies were compared among cases and controls using PLINK program. Ninety-three human periapical granulomas and 24 healthy periodontal ligament tissues collected post-operatively were used for mRNA expression analyses of IL1B. Results A SNP in IL1B (rs1143643) showed allelic (P=0.02) and genotypic (P=0.004) association with cases of deep caries and periapical lesions. We also observed altered transmission of IL1B marker haplotypes (P = 0.02) in these individuals. IL1B was highly expressed in granulomas (P<0.001). Conclusions Variations in IL1B may be associated with periapical lesion formation in individuals with untreated deep carious lesions. Future studies could help predict host susceptibility to developing periapical lesions. PMID:25476976
Rahman, Mokhlasur; Huys, Geert; Rahman, Motiur; Albert, M. John; Kühn, Inger; Möllby, Roland
2007-01-01
The persistence and transmission of Aeromonas in a duckweed aquaculture-based hospital sewage water treatment plant in Bangladesh was studied. A total of 670 samples from different sites of the hospital sewage water treatment plant, from feces of hospitalized children suffering from diarrhea, from environmental control ponds, and from feces of healthy humans were collected over a period of three years. In total, 1,315 presumptive Aeromonas isolates were biochemically typed by the PhenePlate rapid screening system (PhP-AE). A selection of 90 representative isolates was further analyzed with PhenePlate (PhP) extended typing (PhP-48), fatty acid methyl ester analysis, and amplified fragment length polymorphism (AFLP) fingerprinting. In addition, the prevalence of the putative virulence factors hemolysin and cytotoxin and the presence of the cytolytic enterotoxin gene (AHCYTOEN) were analyzed. Aeromonas was found at all sites of the treatment plant, in 40% of the samples from environmental control ponds, in 8.5% of the samples from hospitalized children suffering from diarrhea, and in 3.5% of samples from healthy humans. A significantly high number of Aeromonas bacteria was found in duckweed, which indicates that duckweed may serve as a reservoir for these bacteria. PhP-AE typing allowed identification of more than 192 distinct PhP types, of which 18 major PhP types (MTs) were found in multiple sites and during several occasions. AFLP fingerprinting revealed the prevalence of genotypically indistinguishable Aeromonas isolates among certain PhP MTs recovered from different sampling occasions and/or at multiple sites. Hemolytic and cytotoxic activities were observed in 43% of the tested strains, whereas 29% possessed the cytolytic enterotoxin gene AHCYTOEN. Collectively, two specific MTs associated with diarrhea were shown to exhibit high cytotoxicity. Furthermore, all tested isolates of these major types were positive for the cytolytic enterotoxin gene. In conclusion, our data indicate that certain phenotypically and genotypically stable clonal lineages of Aeromonas have persisted in the treatment system for a prolonged period and might spread from the hospitalized children suffering from diarrhea to fish produced for human consumption through the sewage water treatment system. PMID:17194839
Mat Azis, Norhidayah; Pung, Hui P; Abdul Rachman, Abdul R; Amin Nordin, Syafinaz; Sarchio, Seri N E; Suhaili, Zarizal; Mohd Desa, Mohd N
The aim of the present study was to assess and compare the antimicrobial susceptibility pattern against a panel of antibiotics and molecular and methicillin resistance-associated genotypes of 120 carriage S. aureus isolates previously isolated from a student population at two isolation events within a one-month interval. The antibiotic susceptibility of isolates was determined using the Kirby-Bauer disc-diffusion method (cefoxitin by Etest). The MRSA was screened using polymerase chain reaction for the presence of the mecA gene. The mecA-positive isolates were subjected to staphylococcal cassette chromosome (SCC) mec typing, multilocus sequence typing (MLST) and eBURST analysis. All isolates were characterized for the presence of the Panton-Valentine leukocidin (PVL) gene, an enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) pattern and the spa type. For the two occasions where S. aureus was isolated, the highest frequency of resistance was observed for penicillin (70% and 65%, respectively), with a lower rate against erythromycin and tetracycline (<12%). All isolates were susceptible to ciprofloxacin and gentamycin. As for methicillin resistance, eight isolates had minimum inhibitory concentrations (MIC) of resistant categories, but 10 isolates (8.33%) were positive for the mecA gene. The mecA-positive isolates belonged to SCCmec types I (n=9) and V (n=1). MLST was resolved for only three MRSAs, ST508 (n=1), ST88 (n=1) and ST96 (n=1). The results of the eBURST analysis showed that the MRSA isolates analyzed in the present study were potentially related to MRSA identified in other countries. Approximately half of the persistent S. aureus carriers harbored S. aureus of a similar spa type in the respective individuals during both isolation events. A persistent antimicrobial pattern and limited distinct MRSAs were observed over the short study period. The latter frequently exhibited SCCmec type I, commonly associated with hospital-acquired (HA) characteristics, but further delineation is needed to justify the origins of these bacteria. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.
The effects of probiotics in lactose intolerance: A systematic review.
Oak, Sophia J; Jha, Rajesh
2018-02-09
Over 60 percent of the human population has a reduced ability to digest lactose due to low levels of lactase enzyme activity. Probiotics are live bacteria or yeast that supplements the gastrointestinal flora. Studies have shown that probiotics exhibit various health beneficial properties such as improvement of intestinal health, enhancement of the immune responses, and reduction of serum cholesterol. Accumulating evidence has shown that probiotic bacteria in fermented and unfermented milk products can be used to alleviate the clinical symptoms of lactose intolerance (LI). In this systematic review, the effectiveness of probiotics in the treatment of LI was evaluated using 15 randomized double-blind studies. Eight probiotic strains with the greatest number of proven benefits were studied. Results showed varying degrees of efficacy but an overall positive relationship between probiotics and lactose intolerance.
Effects of Clonal Reproduction on Evolutionary Lag and Evolutionary Rescue.
Orive, Maria E; Barfield, Michael; Fernandez, Carlos; Holt, Robert D
2017-10-01
Evolutionary lag-the difference between mean and optimal phenotype in the current environment-is of keen interest in light of rapid environmental change. Many ecologically important organisms have life histories that include stage structure and both sexual and clonal reproduction, yet how stage structure and clonality interplay to govern a population's rate of evolution and evolutionary lag is unknown. Effects of clonal reproduction on mean phenotype partition into two portions: one that is phenotype dependent, and another that is genotype dependent. This partitioning is governed by the association between the nonadditive genetic plus random environmental component of phenotype of clonal offspring and their parents. While clonality slows phenotypic evolution toward an optimum, it can dramatically increase population survival after a sudden step change in optimal phenotype. Increased adult survival slows phenotypic evolution but facilitates population survival after a step change; this positive effect can, however, be lost given survival-fecundity trade-offs. Simulations indicate that the benefits of increased clonality under environmental change greatly depend on the nature of that change: increasing population persistence under a step change while decreasing population persistence under a continuous linear change requiring de novo variation. The impact of clonality on the probability of persistence for species in a changing world is thus inexorably linked to the temporal texture of the change they experience.
Rising CO2 widens the transpiration-photosynthesis optimality space
NASA Astrophysics Data System (ADS)
de Boer, Hugo J.; Eppinga, Maarten B.; Dekker, Stefan C.
2016-04-01
Stomatal conductance (gs) and photosynthetic biochemistry, typically expressed by the temperature-adjusted maximum rates of carboxylation (V cmax) and electron transport (Jmax), are key traits in land ecosystem models. Contrary to the many approaches available for simulating gs responses, the biochemical parameters V cmax and Jmax are often treated as static traits in ecosystem models. However, observational evidence indicates that V cmax and Jmax respond to persistent changes in atmospheric CO2. Hence, ecosystem models may be improved by incorporating coordinated responses of photosynthetic biochemistry and gs to atmospheric CO2. Recently, Prentice et al. (2014) proposed an optimality framework (referred to as the Prentice framework from here on) to predict relationships between V cmax and gs based on Fick's law, Rubisco-limited photosynthesis and the carbon costs of transpiration and photosynthesis. Here we show that this framework is, in principle, suited to predict CO2-induced changes in the V cmax -gs relationships. The framework predicts an increase in the V cmax:gs-ratio with higher atmospheric CO2, whereby the slope of this relationship is determined by the carbon costs of transpiration and photosynthesis. For our empirical analyses we consider that the carbon cost of transpiration is positively related to the plant's Huber value (sapwood area/leaf area), while the carbon cost of photosynthesis is positively related to the maintenance cost of the photosynthetic proteins. We empirically tested the predicted effect of CO2 on the V cmax:gs-ratio in two genotypes of Solanum dulcamara (bittersweet) that were grown from seeds to maturity under 200, 400 and 800 ppm CO2 in walk-in growth chambers with tight control on light, temperature and humidity. Seeds of the two Solanum genotypes were obtained from two distinct natural populations; one adapted to well-drained sandy soil (the 'dry' genotype) and one adapted to poorly-drained clayey soil (the 'wet' genotype). Measurements of gs and V cmax were obtained with a portable photosynthesis system. Our empirical results support the prediction that the V cmax:gs-ratio increases with higher CO2 in both Solanum genotypes. The 'dry' genotype revealed a significantly higher Huber value and lower V cmax than the 'wet' genotype at each CO2 growth level. Moreover, we found that the down-regulation of V cmax under higher CO2 was stronger in the 'dry' genotype than in the 'wet' genotype, whereas no change in the Huber value was observed between CO2 levels. Consistent with the theoretical trade-off between the resulting costs of transpiration and photosynthesis, we found that the CO2-induced increase in the V cmax:gs-ratio was stronger in the 'wet' genotype than in the 'dry' genotype. Given the divergence of V cmax:gs relationships observed, we conclude that rising atmospheric CO2 may widen the V cmax - gs optimality space available for plants to achieve an optimal trade-off between photosynthesis and transpiration. References Prentice, I. C., Dong, N., Gleason, S. M., Maire, V. and Wright, I. J.: Balancing the costs of carbon gain and water transport: testing a new theoretical framework for plant functional ecology, Ecol. Lett., 17(1), 82-91, 2014.
Drake, Nadia M.; Park, Yoon Jung; Shirali, Aditya S.; Cleland, Thomas A.
2010-01-01
Rasgrf1 is imprinted and expressed preferentially from the paternal allele in neonatal mouse brain. At weaning, expression becomes biallelic. Using a mouse model, we assayed the effects of perturbing imprinted Rasgrf1 expression in mice with the following imprinted expression patterns: monoallelic paternal (wild type), monoallelic maternal (maternal only), biallelic (both alleles transcribed), and null (neither allele transcribed). All genotypes exhibit biallelic expression around weaning. Consequences of this transient imprinting perturbation are manifested as overall size differences that correspond to the amount of neonatal Rasgrf1 expressed and are persistent, extending into adulthood. Biallelic mice are the largest and overexpress Rasgrf1 relative to wild-type mice, null mice are the smallest and underexpress Rasgrf1 as neonates, and the two monoallelically expressing genotypes are intermediate and indistinguishable from one another, in both size and Rasgrf1 expression level. Importantly, these data support one of the key underlying assumptions of the “conflict hypothesis” that describes the evolution of genomic imprinting in mammals and supposes that equivalent amounts of imprinted gene expression produce equivalent phenotypes, regardless of which parental allele is transcribed. Concordant with the difference in overall body size, we identify differences in IGF-1 levels, both in serum protein and as liver transcript, and identify additional differential expression of components upstream of IGF-1 release in the GH/IGF-1 axis. These data suggest that imprinted Rasgrf1 expression affects GH/IGF-1 axis function, and that the consequences of Rasgrf1 inputs to this axis persist beyond the time period when expression is restricted via epigenetic mechanisms, suggesting that proper neonatal Rasgrf1 expression levels are critical for development. PMID:19513790
Selosse, Marc-André; Martin, Francis; Bouchard, Daniel; le Tacon, François
1999-01-01
Ectomycorrhizal fungi have been introduced in forest nurseries to improve seedling growth. Outplanting of inoculated seedlings to forest plantations raises the questions about inoculant persistence and its effects on indigenous fungal populations. We previously showed (M.-A. Selosse et al. Mol. Ecol. 7:561–573, 1998) that the American strain Laccaria bicolor S238N persisted 10 years after outplanting in a French Douglas fir plantation, without introgression or selfing and without fruiting on uninoculated adjacent plots. In the present study, the relevance of those results to sympatric strains was assessed for another part of the plantation, planted in 1985 with seedlings inoculated with the French strain L. bicolor 81306 or left uninoculated. About 720 Laccaria sp. sporophores, collected from 1994 to 1997, were typed by using randomly amplified polymorphic DNA markers and PCR amplification of the mitochondrial and nuclear ribosomal DNAs. All plots were colonized by small spontaneous discrete genotypes (genets). The inoculant strain 81306 abundantly fruited beneath inoculated trees, with possible introgression in indigenous Laccaria populations but without selfing. In contrast to our previous survey of L. bicolor S238N, L. bicolor 81306 colonized a plot of uninoculated trees. Meiotic segregation analysis verified that the invading genet was strain 81306 (P < 0.00058), implying a vegetative growth of 1.1 m · year−1. This plot was also invaded in 1998 by strain S238N used to inoculate other trees of the plantation. Five other uninoculated plots were free of these inoculant strains. The fate of inoculant strains thus depends less on their geographic origin than on unknown local factors. PMID:10223992
Kumar, Nitin; Miyajima, Fabio; He, Miao; Roberts, Paul; Swale, Andrew; Ellison, Louise; Pickard, Derek; Smith, Godfrey; Molyneux, Rebecca; Dougan, Gordon; Parkhill, Julian; Wren, Brendan W; Parry, Christopher M; Pirmohamed, Munir; Lawley, Trevor D
2016-03-15
Accurate tracking of Clostridium difficile transmission within healthcare settings is key to its containment but is hindered by the lack of discriminatory power of standard genotyping methods. We describe a whole-genome phylogenetic-based method to track the transmission of individual clones in infected hospital patients from the epidemic C. difficile 027/ST1 lineage, and to distinguish between the 2 causes of recurrent disease, relapse (same strain), or reinfection (different strain). We monitored patients with C. difficile infection in a UK hospital over a 2-year period. We performed whole-genome sequencing and phylogenetic analysis of 108 strains isolated from symptomatic patients. High-resolution phylogeny was integrated with in-hospital transfers and contact data to create an infection network linking individual patients and specific hospital wards. Epidemic C. difficile 027/ST1 caused the majority of infections during our sampling period. Integration of whole-genome single nucleotide polymorphism (SNP) phylogenetic analysis, which accurately discriminated between 27 distinct SNP genotypes, with patient movement and contact data identified 32 plausible transmission events, including ward-based contamination (66%) or direct donor-recipient contact (34%). Highly contagious donors were identified who contributed to the persistence of clones within distinct hospital wards and the spread of clones between wards, especially in areas of intense turnover. Recurrent cases were identified between 4 and 26 weeks, highlighting the limitation of the standard <8-week cutoff used for patient diagnosis and management. Genome-based infection tracking to monitor the persistence and spread of C. difficile within healthcare facilities could inform infection control and patient management. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America.
Smit, M M; Ekenstedt, K J; Minor, K M; Lim, C K; Leegwater, Paj; Furrow, E
2018-04-01
Persistent Müllerian duct syndrome (PMDS) is a sex-limited disorder in which males develop portions of the female reproductive tract. Important consequences of PMDS are cryptorchidism and its sequelae of infertility and increased risk of testicular cancer. Anti-Müllerian hormone (AMH) and its receptor (AMHR2) induce the regression of the Müllerian ducts in male embryos. In Miniature Schnauzer dogs, the genetic basis has been identified as an autosomal recessive nonsense mutation in AMHR2, but the allele frequency of the mutation is unknown. Thus, the primary objective of this study was to estimate the prevalence of the AMHR2 mutation in North American Miniature Schnauzers, in order to ascertain the value of genetic testing in this breed. An additional objective was to determine whether mutations in AMH or AMHR2 were responsible for PMDS in a Belgian Malinois; this would aid development of a genetic test for the Belgian Malinois breed. Genomic DNA from 216 Miniature Schnauzers (including one known PMDS case) was genotyped for the AMHR2 mutation, and DNA from a single PMDS-affected Belgian Malinois was sequenced for all coding exons of AMH and AMHR2. The Miniature Schnauzer cohort had an AMHR2 mutation allele frequency of 0.16 and a carrier genotypic frequency of 0.27. The genetic basis for PMDS in the Belgian Malinois was not determined, as no coding or splicing mutations were identified in either AMH or AMHR2. These findings support a benefit to AMHR2 mutation testing Miniature Schnauzers used for breeding or with cryptorchidism. © 2017 Blackwell Verlag GmbH.
Weitzner, Erica; McKenna, Donna; Nowakowski, John; Scavarda, Carol; Dornbush, Rhea; Bittker, Susan; Cooper, Denise; Nadelman, Robert B; Visintainer, Paul; Schwartz, Ira; Wormser, Gary P
2015-12-15
Lyme disease patients with erythema migrans are said to have post-treatment Lyme disease symptoms (PTLDS) if there is persistence of subjective symptoms for at least 6 months following antibiotic treatment and resolution of the skin lesion. The purpose of this study was to characterize PTLDS in patients with culture-confirmed early Lyme disease followed for >10 years. Adult patients with erythema migrans with a positive skin or blood culture for Borrelia burgdorferi were enrolled in a prospective study beginning in 1991 and followed up at 6 months and annually thereafter to determine the long-term outcome of this infection. The genotype of the infecting strain of B. burgdorferi was evaluated in subjects with PTLDS. One hundred twenty-eight subjects with culture-confirmed early Lyme disease, of whom 55% were male, were followed for a mean ± SD of 14.98 ± 2.71 years (median = 15 years; range = 11-20 years). Fourteen (10.9%) were regarded as having possible PTLDS, but only 6 (4.7%) had PTLDS documented at their last study visit. Nine (64.3%) had only a single symptom. None of the 6 with PTLDS at their last visit was considered to be functionally impaired by the symptom(s). PTLDS was not associated with a particular genotype of B. burgdorferi. PTLDS may persist for >10 years in some patients with culture-confirmed early Lyme disease. Such long-standing symptoms were not associated with functional impairment or a particular strain of B. burgdorferi. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Leenders, Alexander C. A. P.; van Belkum, Alex; Behrendt, Myra; Luijendijk, Ad; Verbrugh, Henri A.
1999-01-01
After five patients were diagnosed with nosocomial invasive aspergillosis caused by Aspergillus fumigatus and A. flavus, a 14-month surveillance program for pathogenic and nonpathogenic fungal conidia in the air within and outside the University Hospital in Rotterdam (The Netherlands) was begun. A. fumigatus isolates obtained from the Department of Hematology were studied for genetic relatedness by randomly amplified polymorphic DNA (RAPD) analysis. This was repeated with A. fumigatus isolates contaminating culture media in the microbiology laboratory. The density of the conidia of nonpathogenic fungi in the outside air showed a seasonal variation: higher densities were measured during the summer, while lower densities were determined during the fall and winter. Hardly any variation was found in the numbers of Aspergillus conidia. We found decreasing numbers of conidia when comparing air from outside the hospital to that inside the hospital and when comparing open areas within the hospital to the closed department of hematology. The increase in the number of patients with invasive aspergillosis could not be explained by an increase in the number of Aspergillus conidia in the outside air. The short-term presence of A. flavus can only be explained by the presence of a point source, which was probably patient related. Genotyping A. fumigatus isolates from the department of hematology showed that clonally related isolates were persistently present for more than 1 year. Clinical isolates of A. fumigatus obtained during the outbreak period were different from these persistent clones. A. fumigatus isolates contaminating culture media were all genotypically identical, indicating a causative point source. Knowledge of the epidemiology of Aspergillus species is necessary for the development of strategies to prevent invasive aspergillosis. RAPD fingerprinting of Aspergillus isolates can help to determine the cause of an outbreak of invasive aspergillosis. PMID:10325319
Persistence of Plasmodium falciparum parasites in infected pregnant Mozambican women after delivery.
Serra-Casas, Elisa; Menéndez, Clara; Dobaño, Carlota; Bardají, Azucena; Quintó, Llorenç; Quintó, Llorençc; Ordi, Jaume; Sigauque, Betuel; Cisteró, Pau; Mandomando, Inacio; Alonso, Pedro L; Mayor, Alfredo
2011-01-01
Pregnant women are susceptible to Plasmodium falciparum parasites that sequester in the placenta. The massive accumulation of infected erythrocytes in the placenta has been suggested to trigger the deleterious effects of malaria in pregnant women and their offspring. The risk of malaria is also high during the postpartum period, although mechanisms underlying this susceptibility are not known. Here, we aimed to identify host factors contributing to the risk of postpartum infections and to determine the origin of postpartum parasites by comparing their genotypes with those present at the time of delivery. To address this, blood samples were collected at delivery (n = 402) and postpartum (n = 354) from Mozambican women enrolled in a trial of intermittent preventive treatment in pregnancy (IPTp). P. falciparum was detected by real-time quantitative PCR (qPCR), and the parasite merozoite surface protein 1 (msp-1) and msp-2 genes were genotyped. Fifty-seven out of 354 (16%) women were infected postpartum as assessed by qPCR, whereas prevalence by optical microscopy was only 4%. Risk of postpartum infection was lower in older women (odds ratio [OR] = 0.34, 95% confidence interval [CI] = 0.15 to 0.81) and higher in women with a placental infection at delivery (OR = 4.20, 95% CI = 2.19 to 8.08). Among 24 women with matched infections, 12 (50%) were infected postpartum with at least one parasite strain that was also present in their placentas. These results suggest that parasites infecting pregnant women persist after delivery and increase the risk of malaria during the postpartum period. Interventions that reduce malaria during pregnancy may translate into a lower risk of postpartum infection.
Marandino, Ana; Tomás, Gonzalo; Panzera, Yanina; Greif, Gonzalo; Parodi-Talice, Adriana; Hernández, Martín; Techera, Claudia; Hernández, Diego; Pérez, Ruben
2017-10-01
Infectious bronchitis virus (Gammacoronavirus, Coronaviridae) is a genetically variable RNA virus that causes one of the most persistent respiratory diseases in poultry. The virus is classified in genotypes and lineages with different epidemiological relevance. Two lineages of the GI genotype (11 and 16) have been widely circulating for decades in South America. GI-11 is an exclusive South American lineage while the GI-16 lineage is distributed in Asia, Europe and South America. Here, we obtained the whole genome of two Uruguayan strains of the GI-11 and GI-16 lineages using Illumina high-throughput sequencing. The strains here sequenced are the first obtained in South America for the infectious bronchitis virus and provide new insights into the origin, spreading and evolution of viral variants. The complete genome of the GI-11 and GI-16 strains have 27,621 and 27,638 nucleotides, respectively, and possess the same genomic organization. Phylogenetic incongruence analysis reveals that both strains have a mosaic genome that arose by recombination between Euro Asiatic strains of the GI-16 lineage and ancestral South American GI-11 viruses. The recombination occurred in South America and produced two viral variants that have retained the full-length S1 sequences of the parental lineages but are extremely similar in the rest of their genomes. These recombinant virus have been extraordinary successful, persisting in the continent for several years with a notorious wide geographic distribution. Our findings reveal a singular viral dynamics and emphasize the importance of complete genomic characterization to understand the emergence and evolutionary history of viral variants. Copyright © 2017 Elsevier B.V. All rights reserved.
Genetic diversity of Afrikaner cattle in southern Africa.
Pienaar, Lené; Grobler, J Paul; Scholtz, Michiel M; Swart, Hannelize; Ehlers, Karen; Marx, Munro; MacNeil, Michael D; Neser, Frederick W C
2018-02-01
The Afrikaner is an indigenous South African breed of "Sanga" type beef cattle along with breeds such as the Drakensberger and Nguni. Six composite breeds have been developed from crosses with the Afrikaner. Additionally, Afrikaner has been the base from which exotic breeds were established in South Africa through backcrossing. The study examined genetic diversity of Afrikaner cattle by genotyping 1257 animals from 27 herds in different geographic areas of South Africa and Namibia using 11 microsatellite markers. Multiple-locus assignment, performed using the Bayesian clustering algorithm of STRUCTURE, revealed three underlying genotypic groups. These groups were not geographically localized. Across herds and markers, the proportion of unbiased heterozygosity ranged from 0.49 to 0.72 averaging 0.57; mean number of alleles per locus ranged from 3.18 to 7.09, averaging 4.81; and allelic richness ranged from 2.35 to 3.38, averaging 2.67. It is concluded that a low inbreeding level of 2.7% and a moderate to high degree of variation still persists within the Afrikaner cattle breed, despite the recent decline in numbers of animals.
Nonfermented milk and other dairy products: associations with all-cause mortality.
Tognon, Gianluca; Nilsson, Lena M; Shungin, Dmitry; Lissner, Lauren; Jansson, Jan-Håkan; Renström, Frida; Wennberg, Maria; Winkvist, Anna; Johansson, Ingegerd
2017-06-01
Background: A positive association between nonfermented milk intake and increased all-cause mortality was recently reported, but overall, the association between dairy intake and mortality is inconclusive. Objective: We studied associations between intake of dairy products and all-cause mortality with an emphasis on nonfermented milk and fat content. Design: A total of 103,256 adult participants (women: 51.0%) from Northern Sweden were included (7121 deaths; mean follow-up: 13.7 y). Associations between all-cause mortality and reported intakes of nonfermented milk (total or by fat content), fermented milk, cheese, and butter were tested with the use of Cox proportional hazards models that were adjusted for age, sex, body mass index, smoking status, education, energy intake, examination year, and physical activity. To circumvent confounding, Mendelian randomization was applied in a subsample via the lactase LCT - 13910 C/T single nucleotide polymorphism that is associated with lactose tolerance and milk intake. Results: High consumers of nonfermented milk (≥2.5 times/d) had a 32% increased hazard (HR: 1.32; 95% CI: 1.18, 1.48) for all-cause mortality compared with that of subjects who consumed milk ≤1 time/wk. The corresponding value for butter was 11% (HR: 1.11; 95% CI: 1.07, 1.21). All nonfermented milk-fat types were independently associated with increased HRs, but compared with full-fat milk, HRs were lower in consumers of medium- and low-fat milk. Fermented milk intake (HR: 0.90; 95% CI: 0.86, 0.94) and cheese intake (HR: 0.93; 95% CI: 0.91, 0.96) were negatively associated with mortality. Results were slightly attenuated by lifestyle adjustments but were robust in sensitivity analyses. Mortality was not significantly associated with the LCT -13910 C/T genotype in the smaller subsample. The amount and type of milk intake was associated with lifestyle variables. Conclusions: In the present Swedish cohort study, intakes of nonfermented milk and butter are associated with higher all-cause mortality, and fermented milk and cheese intakes are associated with lower all-cause mortality. Residual confounding by lifestyle cannot be excluded, and Mendelian randomization needs to be examined in a larger sample. © 2017 American Society for Nutrition.
Liu, Hong; Wang, Jun; Mou, Daolin; Che, Lianqiang; Fang, Zhengfeng; Feng, Bin; Lin, Yan; Xu, Shengyu; Li, Jian; Wu, De
2017-01-01
This study was conducted to explore whether exposure to bisphenol A (BPA) during pregnancy could change intestinal digestion and absorption function in offspring using pigs as a model, and whether methyl donor (MET) could counteract the BPA-induced impacts. Fifty Landrace × Yorkshire sows were divided into four dietary groups throughout gestation: control diet (CON); control diet supplemented with BPA (50 mg/kg); control diet supplemented with MET (3 g/kg betaine, 400 mg/kg choline, 150 μg/kg vitamin B12, and 15 mg/kg folic acid); and control diet with BPA and MET supplementation (BPA + MET). Intestine samples were collected from pigs’ offspring at birth and weaning. Maternal BPA exposure during pregnancy significantly reduced the ratio of jejunum villus height to crypt depth, decreased the jejunum sucrase activity, down-regulated the mRNA expression of jejunum peptide transporter 1 (Pept1) and DNA methyl transferase 3a (DNMT3a), and decreased the DNA methylation level of jejunum Pept1 in offspring (p < 0.05). Maternal MET supplementation significantly raised the ratio of villus height to crypt depth in jejunum and ileum, improved the jejunum lactase activity, up-regulated the mRNA expression of jejunum Pept1, lactase (LCT), DNMT1, DNMT3a, and methylenetetrahydrofolate reductase (MTHFR), and increased the DNA methylation level of jejunum Pept1 in offspring (p < 0.05). However, the ratio of jejunum villus height to crypt depth was higher in BPA + MET treatment compared with CON and BPA treatment (p < 0.05). Meanwhile, there was no difference in the jejunum sucrase activity, the mRNA expression of jejunum Pept1 and DNMT3a, and the DNA methylation level of jejunum Pept1 between CON and BPA + MET treatment. These results indicated that maternal exposure to BPA during gestation might suppress offspring’s intestinal digestion and absorption function, whereas supplementation of MET could counteract these damages, which might be associated with DNA methylation. PMID:28445388
Tsuji, Akihiko; Tominaga, Keiko; Nishiyama, Nami; Yuasa, Keizo
2013-01-01
Although many endo-ß-1,4-glucanases have been isolated in invertebrates, their cellulolytic systems are not fully understood. In particular, gastropod feeding on seaweed is considered an excellent model system for production of bioethanol and renewable bioenergy from third-generation feedstocks (microalgae and seaweeds). In this study, enzymes involved in the conversion of cellulose and other polysaccharides to glucose in digestive fluids of the sea hare (Aplysia kurodai) were screened and characterized to determine how the sea hare obtains glucose from sea lettuce (Ulva pertusa). Four endo-ß-1,4-glucanases (21K, 45K, 65K, and 95K cellulase) and 2 ß-glucosidases (110K and 210K) were purified to a homogeneous state, and the synergistic action of these enzymes during cellulose digestion was analyzed. All cellulases exhibited cellulase and lichenase activities and showed distinct cleavage specificities against cellooligosaccharides and filter paper. Filter paper was digested to cellobiose, cellotriose, and cellotetraose by 21K cellulase, whereas 45K and 65K enzymes hydrolyzed the filter paper to cellobiose and glucose. 210K ß-glucosidase showed unique substrate specificity against synthetic and natural substrates, and 4-methylumbelliferyl (4MU)-ß-glucoside, 4MU–ß-galactoside, cello-oligosaccharides, laminarin, and lichenan were suitable substrates. Furthermore, 210K ß-glucosidase possesses lactase activity. Although ß-glucosidase and cellulase are necessary for efficient hydrolysis of carboxymethylcellulose to glucose, laminarin is hydrolyzed to glucose only by 210K ß-glucosidase. Kinetic analysis of the inhibition of 210K ß-glucosidase by D-glucono-1,5-lactone suggested the presence of 2 active sites similar to those of mammalian lactase-phlorizin hydrolase. Saccharification of sea lettuce was considerably stimulated by the synergistic action of 45K cellulase and 210K ß-glucosidase. Our results indicate that 45K cellulase and 210K ß-glucosidase are the core components of the sea hare digestive system for efficient production of glucose from sea lettuce. These findings contribute important new insights into the development of biofuel processing biotechnologies from seaweed. PMID:23762366
Whole-Genome Sequencing and Variant Analysis of Human Papillomavirus 16 Infections.
van der Weele, Pascal; Meijer, Chris J L M; King, Audrey J
2017-10-01
Human papillomavirus (HPV) is a strongly conserved DNA virus, high-risk types of which can cause cervical cancer in persistent infections. The most common type found in HPV-attributable cancer is HPV16, which can be subdivided into four lineages (A to D) with different carcinogenic properties. Studies have shown HPV16 sequence diversity in different geographical areas, but only limited information is available regarding HPV16 diversity within a population, especially at the whole-genome level. We analyzed HPV16 major variant diversity and conservation in persistent infections and performed a single nucleotide polymorphism (SNP) comparison between persistent and clearing infections. Materials were obtained in the Netherlands from a cohort study with longitudinal follow-up for up to 3 years. Our analysis shows a remarkably large variant diversity in the population. Whole-genome sequences were obtained for 57 persistent and 59 clearing HPV16 infections, resulting in 109 unique variants. Interestingly, persistent infections were completely conserved through time. One reinfection event was identified where the initial and follow-up samples clustered differently. Non-A1/A2 variants seemed to clear preferentially ( P = 0.02). Our analysis shows that population-wide HPV16 sequence diversity is very large. In persistent infections, the HPV16 sequence was fully conserved. Sequencing can identify HPV16 reinfections, although occurrence is rare. SNP comparison identified no strongly acting effect of the viral genome affecting HPV16 infection clearance or persistence in up to 3 years of follow-up. These findings suggest the progression of an early HPV16 infection could be host related. IMPORTANCE Human papillomavirus 16 (HPV16) is the predominant type found in cervical cancer. Progression of initial infection to cervical cancer has been linked to sequence properties; however, knowledge of variants circulating in European populations, especially with longitudinal follow-up, is limited. By sequencing a number of infections with known follow-up for up to 3 years, we gained initial insights into the genetic diversity of HPV16 and the effects of the viral genome on the persistence of infections. A SNP comparison between sequences obtained from clearing and persistent infections did not identify strongly acting DNA variations responsible for these infection outcomes. In addition, we identified an HPV16 reinfection event where sequencing of initial and follow-up samples showed different HPV16 variants. Based on conventional genotyping, this infection would incorrectly be considered a persistent HPV16 infection. In the context of vaccine efficacy and monitoring studies, such infections could potentially cause reduced reported efficacy or efficiency. Copyright © 2017 van der Weele et al.
Genetic variability in E6, E7 and L1 genes of Human Papillomavirus 62 and its prevalence in Mexico.
Artaza-Irigaray, Cristina; Flores-Miramontes, María Guadalupe; Olszewski, Dominik; Magaña-Torres, María Teresa; López-Cardona, María Guadalupe; Leal-Herrera, Yelda Aurora; Piña-Sánchez, Patricia; Jave-Suárez, Luis Felipe; Aguilar-Lemarroy, Adriana
2017-01-01
Human papillomavirus (HPV) is the main etiological agent of cervical cancer, the third most common cancer among women globally and the second most frequent in Mexico. Persistent infection with high-risk HPV genotypes is associated with premalignant lesions and cervical cancer development. HPVs considered as low risk or not yet classified, are often found in coinfection with different HPV genotypes. Indeed, HPV62 is one of the most prevalent HPV detected in some countries, but there is limited information about its prevalence in other regions and there are no HPV62 variants currently described. The aim of this study was to determine the prevalence of HPV62 in cervical samples from Mexican women and to identify mutations in the L1, E6 and E7 genes, which have never been reported in our population. HPV screening was performed by Cobas HPV Test in women who attended prevention health programs and dysplasia clinics. All HPV positive samples ( n = 491) and 87 additional cervical cancer samples were then genotyped with Linear Array HPV Genotyping test. Some samples were selected to corroborate genotyping by Next-Generation sequencing. On the other hand, nucleotide changes in L1, E6 and E7 genes were determined using PCR, Sanger sequencing and analysis with the CLC-MainWorkbench 7.6.1 software. L1 protein structure was predicted with the I-TASSER server. Using Linear Array, HPV62 prevalence was 7.6% in general population, 8% in Cervical Intraepithelial Neoplasia grade 1 (CIN1) samples and 4.6% in cervical samples. The presence of HPV62 was confirmed with Next-Generation sequencing. Regarding L1 gene, novel sequence variations were detected, but they did not alter the tertiary structure of the protein. Moreover, several nucleotide substitutions were found in E6 and E7 genes compared to reference HPV62 genomic sequence. Specifically, three non-synonymous sequence variations were detected, two in E6 and one in E7. HPV62 is a frequent HPV genotype found mainly in general population and in women with CIN1, and in 90.5% of the cases it was found in coinfection with other HPVs. Novel nucleotide changes in its L1, E6 and E7 genes were detected, some of them lead to changes in the protein sequence.
Martínez-Suárez, Joaquín V; Ortiz, Sagrario; López-Alonso, Victoria
2016-01-01
The persistence of certain strains of Listeria monocytogenes, even after the food processing environment has been cleaned and disinfected, suggests that this may be related to phenomena that reduce the concentration of the disinfectants to subinhibitory levels. This includes (i) the existence of environmental niches or reservoirs that are difficult for disinfectants to reach, (ii) microorganisms that form biofilms and create microenvironments in which adequate concentrations of disinfectants cannot be attained, and (iii) the acquisition of resistance mechanisms in L. monocytogenes, including those that lead to a reduction in the intracellular concentration of the disinfectants. The only available data with regard to the resistance of L. monocytogenes to disinfectants applied in food production environments refer to genotypic resistance to quaternary ammonium compounds (QACs). Although there are several well-characterized efflux pumps that confer resistance to QACs, it is a low-level resistance that does not generate resistance to QACs at the concentrations applied in the food industry. However, dilution in the environment and biodegradation result in QAC concentration gradients. As a result, the microorganisms are frequently exposed to subinhibitory concentrations of QACs. Therefore, the low-level resistance to QACs in L. monocytogenes may contribute to its environmental adaptation and persistence. In fact, in certain cases, the relationship between low-level resistance and the environmental persistence of L. monocytogenes in different food production chains has been previously established. The resistant strains would have survival advantages in these environments over sensitive strains, such as the ability to form biofilms in the presence of increased biocide concentrations.
Martínez-Suárez, Joaquín V.; Ortiz, Sagrario; López-Alonso, Victoria
2016-01-01
The persistence of certain strains of Listeria monocytogenes, even after the food processing environment has been cleaned and disinfected, suggests that this may be related to phenomena that reduce the concentration of the disinfectants to subinhibitory levels. This includes (i) the existence of environmental niches or reservoirs that are difficult for disinfectants to reach, (ii) microorganisms that form biofilms and create microenvironments in which adequate concentrations of disinfectants cannot be attained, and (iii) the acquisition of resistance mechanisms in L. monocytogenes, including those that lead to a reduction in the intracellular concentration of the disinfectants. The only available data with regard to the resistance of L. monocytogenes to disinfectants applied in food production environments refer to genotypic resistance to quaternary ammonium compounds (QACs). Although there are several well-characterized efflux pumps that confer resistance to QACs, it is a low-level resistance that does not generate resistance to QACs at the concentrations applied in the food industry. However, dilution in the environment and biodegradation result in QAC concentration gradients. As a result, the microorganisms are frequently exposed to subinhibitory concentrations of QACs. Therefore, the low-level resistance to QACs in L. monocytogenes may contribute to its environmental adaptation and persistence. In fact, in certain cases, the relationship between low-level resistance and the environmental persistence of L. monocytogenes in different food production chains has been previously established. The resistant strains would have survival advantages in these environments over sensitive strains, such as the ability to form biofilms in the presence of increased biocide concentrations. PMID:27199964
Enteropathogenic Escherichia coli: foe or innocent bystander?
Hu, Jia; Torres, Alfredo G.
2015-01-01
Enteropathogenic Escherichia coli (EPEC) remain one the most important pathogens infecting children and they are one of the main causes of persistent diarrhea worldwide. Historically, typical EPEC (tEPEC), defined as those isolates with the attaching and effacement (A/E) genotype (eae+), which possess bfpA+ and lack the stx- genes are found strongly associated with diarrheal cases. However, occurrence of atypical EPEC (aEPEC; eae+ bfpA- stx-) in diarrheal and asymptomatic hosts has made investigators question the role of these pathogens in human disease. Current epidemiological data is helping answering the question whether EPEC is mainly a foe or an innocent bystander during infection. PMID:25726041
Cardiac magnetic resonance in hypertrophic cardiomyopathy: current state of the art.
Kwon, Deborah H; Desai, Milind Y
2010-01-01
Hypertrophic cardiomyopathy is a complex disorder with significant heterogeneity in clinical characteristics and natural history. Traditionally, the diagnosis has been based on clinical assessment and echocardiography; however, persistent challenges in its noninvasive evaluation remain. Hence, improved diagnostic techniques could lead to better risk stratification of patients, which would potentially identify patients likely to benefit from effective therapies. Recent studies have demonstrated the increasing utility of cardiac magnetic resonance in the management of this disease. With the increasing utilization of genetics, cardiac magnetic resonance is likely to play an even more important role in discerning the subtle morphologic differences seen in such patients with similar genotypic profiles.
Dong, Danfeng; Peng, Yibing; Zhang, Lihua; Jiang, Cen; Wang, Xuefeng; Mao, Enqiang
2014-01-01
Over the last decade, Clostridium difficile infection (CDI) has emerged as a significant nosocomial infection, yet little has been reported from China. This study aimed to characterize the clinical and microbiological features of CDI from a hospital in Shanghai. Patients with CDI seen between December 2010 and March 2013 were included in this study, of which clinical data were retrospectively collected. The microbiological features of corresponding isolates were analyzed including genotype by multi-locus sequence typing (MLST), antimicrobial susceptibility, toxin production, sporulation capacity, biofilm formation, and motility. Ninety-four cases of CDI were included during this study period, 12 of whom were severe cases. By reviewing the clinical data, all patients were treated empirically with proton pump inhibitor or antibiotics or both, and they were distributed widely across various wards, most frequently to the digestive ward (28/94, 29.79%). Comparing the severe with mild cases, no significant differences were found in the basic epidemiological data or the microbiological features. Among the 94 isolates, 31 were toxin A-negative toxin B-positive all genotyped as ST37. They generated fewer toxins and spores, as well as similar amounts of biofilm and motility percentages, but exhibited highest drug resistance to cephalosporins, quinolones, macrolide-lincosamide and streptogramin (MLSB), and tetracycline. No specific clinical genotype or microbiological features were found in severe cases; antimicrobial resistance could be the primary reason for epidemic strains leading to the dissemination and persistence of CDI.
Lagging adaptation to warming climate in Arabidopsis thaliana.
Wilczek, Amity M; Cooper, Martha D; Korves, Tonia M; Schmitt, Johanna
2014-06-03
If climate change outpaces the rate of adaptive evolution within a site, populations previously well adapted to local conditions may decline or disappear, and banked seeds from those populations will be unsuitable for restoring them. However, if such adaptational lag has occurred, immigrants from historically warmer climates will outperform natives and may provide genetic potential for evolutionary rescue. We tested for lagging adaptation to warming climate using banked seeds of the annual weed Arabidopsis thaliana in common garden experiments in four sites across the species' native European range: Valencia, Spain; Norwich, United Kingdom; Halle, Germany; and Oulu, Finland. Genotypes originating from geographic regions near the planting site had high relative fitness in each site, direct evidence for broad-scale geographic adaptation in this model species. However, genotypes originating in sites historically warmer than the planting site had higher average relative fitness than local genotypes in every site, especially at the northern range limit in Finland. This result suggests that local adaptive optima have shifted rapidly with recent warming across the species' native range. Climatic optima also differed among seasonal germination cohorts within the Norwich site, suggesting that populations occurring where summer germination is common may have greater evolutionary potential to persist under future warming. If adaptational lag has occurred over just a few decades in banked seeds of an annual species, it may be an important consideration for managing longer-lived species, as well as for attempts to conserve threatened populations through ex situ preservation.
Lindesmith, Lisa C; Kocher, Jacob F; Donaldson, Eric F; Debbink, Kari; Mallory, Michael L; Swann, Excel W; Brewer-Jensen, Paul D; Baric, Ralph S
2017-12-05
Human norovirus is a significant public health burden, with >30 genotypes causing endemic levels of disease and strains from the GII.4 genotype causing serial pandemics as the virus evolves new ligand binding and antigenicity features. During 2014-2015, genotype GII.17 cluster IIIb strains emerged as the leading cause of norovirus infection in select global locations. Comparison of capsid sequences indicates that GII.17 is evolving at previously defined GII.4 antibody epitopes. Antigenicity of virus-like particles (VLPs) representative of clusters I, II, and IIIb GII.17 strains were compared by a surrogate neutralization assay based on antibody blockade of ligand binding. Sera from mice immunized with a single GII.17 VLP identified antigenic shifts between each cluster of GII.17 strains. Ligand binding of GII.17 cluster IIIb VLP was blocked only by antisera from mice immunized with cluster IIIb VLPs. Exchange of residues 393-396 from GII.17.2015 into GII.17.1978 ablated ligand binding and altered antigenicity, defining an important varying epitope in GII.17. The capsid sequence changes in GII.17 strains result in loss of blockade antibody binding, indicating that viral evolution, specifically at residues 393-396, may have contributed to the emergence of cluster IIIb strains and the persistence of GII.17 in human populations. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.
Li, B S; Xiao, Y; Wang, D C; Tan, H L; Ke, B X; He, D M; Ke, C W; Zhang, Y H
2016-09-01
Vibrio cholerae O139 emerged as a causative agent of epidemic cholera in 1992 in India and Bangladesh, and was subsequently reported in China in 1993. The genetic relatedness and molecular characteristics of V. cholerae O139 in Guangdong Province, located in the southern coastal area of China, remains undetermined. In this study, we investigated 136 clinical V. cholerae O139 isolates from 1993 to 2013 in Guangdong. By conventional PCR, 123 (90·4%) isolates were positive for ctxB, ace and zot. Sequencing of the positive amplicons indicated 113 (91·7%) isolates possessed the El Tor allele of ctxB (genotype 3); seven carried the classical ctxB type (genotype 1) and three harboured a novel ctxB type (genotype 5). With respect to tcpA, 123 (90·4%) isolates were positive for the El Tor allele. In addition, pulsed-field gel electrophoresis (with NotI digestion) differentiated the isolates into clusters A and B. Cluster A contained seven of the non-toxigenic isolates from 1998 to 2000; another six non-toxigenic isolates (from 1998 and 2007) and all of the toxigenic isolates formed cluster B. Our results suggest that over a 20-year period, the predominant O139 clinical isolates have maintained a relatively tight clonal structure, although some genetic variance and shift has occurred. Our data highlight the persistence of toxigenic V. cholerae O139 in clinical settings in the southern coastal area of China.
Foster, Nicola L; Baums, Iliana B; Sanchez, Juan A; Paris, Claire B; Chollett, Iliana; Agudelo, Claudia L; Vermeij, Mark J A; Mumby, Peter J
2013-01-01
K-selected species with low rates of sexual recruitment may utilise storage effects where low adult mortality allows a number of individuals to persist through time until a favourable recruitment period occurs. Alternative methods of recruitment may become increasingly important for such species if the availability of favourable conditions for sexual recruitment decline under rising anthropogenic disturbance and climate change. Here, we test the hypotheses that asexual dispersal is an integral life history strategy not only in branching corals, as previously reported, but also in a columnar, 'K-selected' coral species, and that its prevalence is driven by the frequency of severe hurricane disturbance. Montastraea annularis is a long-lived major frame-work builder of Caribbean coral reefs but its survival is threatened by the consequences of climate induced disturbance, such as bleaching, ocean acidification and increased prevalence of disease. 700 M. annularis samples from 18 reefs within the Caribbean were genotyped using six polymorphic microsatellite loci. We demonstrate that asexual reproduction occurs at varying frequency across the species-range and significantly contributes to the local abundance of M. annularis, with its contribution increasing in areas with greater hurricane frequency. We tested several competing hypotheses that might explain the observed pattern of genotypic diversity. 64% of the variation in genotypic diversity among the sites was explained by hurricane incidence and reef slope, demonstrating that large-scale disturbances combine with local habitat characteristics to shape the balance between sexual and asexual reproduction in populations of M. annularis.
Danuser, R; Vogt, H-R; Kaufmann, Th; Peterhans, E; Zanoni, R
2009-03-01
The seroprevalence of pestivirus infections in small ruminants and new world camelids in Switzerland was determined. In 5'059 sera of sheep from 382 herds, 503 sera of goats from 54 herds and 109 sera of alpacas and lamas from 53 herds, population prevalences of 16.1% (sheep), 25.4% (goats) and 4.6% (new world camelids), respectively, were found. In order to determine the source of infection, the serological reactions were further characterized by cross-neutralization against two pestiviruses representing the genotypes BVDV (Bovine Virus Diarrhea Virus)-1 and BDV (Border Disease Virus)-1. Based on the ratio of respective antibody titres, 56.1% of the infections in sheep were induced by a BDV-1, 12.9% by a BVDV-1 and 31.0% by an unresolved pestivirus. In goats, the corresponding proportions were 23.4%, 10.2% and 66.4%, respectively. In Alpacas and Lamas, the source of infection of 1 animal was BDV-1 and that of 4 seropositive animals remained unresolved. In view of the phylogenetic relationship between pestiviruses, the unresolved source of infection is most probably attributable to other pestivirus genotypes circulating in small ruminants and new world camelids. Due to the predominance of pestiviral genotypes other than BVDV-1, the risk of transmission of BVDV from persistently infected small ruminants and new world camelids to cattle appears to be moderate, apart from close direct contact in mixed animal husbandry, communal pasturing and grazing in the Alps.
Lagging adaptation to warming climate in Arabidopsis thaliana
Wilczek, Amity M.; Cooper, Martha D.; Korves, Tonia M.; Schmitt, Johanna
2014-01-01
If climate change outpaces the rate of adaptive evolution within a site, populations previously well adapted to local conditions may decline or disappear, and banked seeds from those populations will be unsuitable for restoring them. However, if such adaptational lag has occurred, immigrants from historically warmer climates will outperform natives and may provide genetic potential for evolutionary rescue. We tested for lagging adaptation to warming climate using banked seeds of the annual weed Arabidopsis thaliana in common garden experiments in four sites across the species’ native European range: Valencia, Spain; Norwich, United Kingdom; Halle, Germany; and Oulu, Finland. Genotypes originating from geographic regions near the planting site had high relative fitness in each site, direct evidence for broad-scale geographic adaptation in this model species. However, genotypes originating in sites historically warmer than the planting site had higher average relative fitness than local genotypes in every site, especially at the northern range limit in Finland. This result suggests that local adaptive optima have shifted rapidly with recent warming across the species’ native range. Climatic optima also differed among seasonal germination cohorts within the Norwich site, suggesting that populations occurring where summer germination is common may have greater evolutionary potential to persist under future warming. If adaptational lag has occurred over just a few decades in banked seeds of an annual species, it may be an important consideration for managing longer-lived species, as well as for attempts to conserve threatened populations through ex situ preservation. PMID:24843140
Bae, In-Gyu; Federspiel, Jerome J.; Miro, Jose M.; Woods, Christopher W.; Park, Lawrence; Rybak, Michael J.; Rude, Thomas H.; Bradley, Suzanne; Bukovski, Suzana; de la Maria, Cristina Garcia; Kanj, Souha S.; Korman, Tony; Marco, Francesc; Murdoch, David R.; Plesiat, Patrick; Rodriguez-Creixems, Marta; Ryan, Suzanne; Steed, Lisa; Tattevin, Pierre; Tripodi, Marie-Françoise; Newton, Karly L.; Corey, G. Ralph; Fowler, Vance G.
2013-01-01
Background The significance of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) is unknown. Using a multinational collection of isolates from methicillin-resistant S. aureus (MRSA) infective endocarditis (IE), we characterized IE patients with and without hVISA, and genotyped the infecting strains. Methods MRSA bloodstream isolates from 65 patients with definite IE from 8 countries underwent PCR for 31 virulence genes, pulsed-field gel electrophoresis, and multilocus sequence typing. hVISA was defined using population analysis profiling (PAP). Results Nineteen (29.2%) of 65 MRSA IE isolates exhibited hVISA by PAP. Isolates from Oceania and Europe were more likely to exhibit hVISA than isolates from the United States (77.8% vs. 35.0% vs. 13.9%; P < .001). The prevalence of hVISA was higher among isolates with a vancomycin minimum inhibitory concentration of 2 mg/L (P = .026). hVISA-infected patients were more likely to have persistent bacteremia (68.4% vs. 37.0%; P = .029) and heart failure (47.4% vs. 19.6%; P = .033). Mortality of hVISA- and non-hVISA-infected patients did not differ (42.1% vs. 34.8%, P = .586). hVISA and non-hVISA isolates were genotypically similar. Conclusions In these analyses, hVISA occurred in over one-quarter of MRSA IE isolates, was associated with certain IE complications, and varied in frequency by geographic region. PMID:19811099
Wood, R R; Arias, C R
2012-07-01
The effect of refrigeration on the seafood-borne pathogen Vibrio vulnificus was investigated in terms of genotype selection and persistence in refrigerated oysters. Naturally occurring numbers of V. vulnificus in oysters from two different locations were compared during a 2-week period under refrigeration conditions. At different time points, V. vulnificus isolates were recovered from oysters and ascribed to 16S rRNA gene type A, B or AB using restriction fragment length polymorphism. Initial V. vulnificus numbers were higher than 10(4) most probable number (MPN) g(-1) and remained unchanged throughout the duration of the study. 16S rRNA gene type B isolates accounted for 53% of the isolates recovered. Amplified fragment length polymorphism analysis confirmed the high genetic variability previously observed within this species but revealed the presence of two main genetic groups within the species that matched 16S rRNA gene ascription. Vibrio vulnificus numbers in oysters did not significantly declined over the shelf life of the product and refrigeration did not select for specific V. vulnificus types. The prevalence of V. vulnificus 16S rRNA gene type B in oysters was higher than previously reported from the same geographic area and was not significantly reduced during the storage period. Vibrio vulnificus is divided into two clear genotypes, regardless of the genetic marker used. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.
Sharif, Alireza; Aghakhani, Arezoo; Velayati, Ali Akbar; Banifazl, Mohammad; Sharif, Mohammad Reza; Razeghi, Effat; Kheirkhah, Davood; Kazemimanesh, Monireh; Bavand, Anahita; Ramezani, Amitis
2016-01-01
The aim of this study was to evaluate the frequency and genotype of human parvovirus B19 and its relation with anemia among Iranian patients under dialysis. Fifty hemodialysis (HD) and 33 peritoneal dialysis (PD) patients were enrolled. B19 IgG and IgM antibodies were assessed by ELISA, and the presence of B19 DNA was evaluated by nested PCR. PCR products were sequenced directly and phylogenetic analysis was performed. In the HD group, the prevalence of B19 antibodies was 54% for IgG and 4% for IgM. B19 DNA was detected in 10% of the cases, and 10% showed B19 IgG and viremia simultaneously. In the PD group, the prevalence of B19 IgG and IgM was 57.6 and 0% respectively, whereas B19 DNA was found in 12.1% of the group. A total of 9.1% showed B19 IgG and viremia concurrently. There was no significant difference regarding anemia and B19 infection in either group. All B19 isolates were clustered in genotype 1A. Our findings indicate that B19 infection plays no role in leading chronic anemia in dialysis patients. However, persistent B19 viremia and the circulation of the same strains in dialysis patients may indicate a potential risk for the contamination of dialysis equipment and nosocomial spread of B19 infection within dialysis units. © 2017 S. Karger AG, Basel.
Dynamics of HPV viral loads reflect the treatment effect of photodynamic therapy in genital warts.
Hu, Zhili; Liu, Lishi; Zhang, Wenjing; Liu, Hui; Li, Junpeng; Jiang, Lifen; Zeng, Kang
2018-03-01
Photodynamic therapy (PDT) has demonstrated good clinical cure rates and low recurrence rates in the treatment of genital warts. Human papillomavirus (HPV) genotypes and viral load assays can reflect the status of persistent or latent infection and serve as a predictor of infection clearance. Specimens from 41 patients with HPV infection were obtained, and the HPV genotypes and viral load were analyzed using real-time polymerase chain reaction (PCR) assays. Traditional treatment, such as radiofrequency, microwave, or surgical therapy, was used to remove the visible lesions, and then PDT treatment was performed every week. HPV DNA testing was performed at every patient visit and the frequency of PDT treatment was determined by changes in HPV viral loads. HPV viral loads decreased significantly after PDT treatment. There were significant differences in HPV viral loads between pretherapy and three or six rounds of PDT treatment. Significant differences were also observed between single and multiple type HPV infection after six rounds of PDT treatment. Patients with single type HPV infection had significantly higher rates of negative HPV DNA test results, as compared with patients with multiple infections after six rounds of PDT treatment; however, there was no difference in recurrence rates between the two groups. Dynamic monitoring of HPV genotypes and viral loads can be used to guide PDT treatment and indicate PDT treatment efficacy in eliminating HPV. Copyright © 2017 Elsevier B.V. All rights reserved.
Tracing the first steps of American sturgeon pioneers in Europe
Ludwig, A.; Arndt, U.; Lippold, S.; Benecke, N.; Debus, L.; King, T.L.; Matsumura, S.
2008-01-01
Background. A Baltic population of Atlantic sturgeon was founded ???1,200 years ago by migrants from North America, but after centuries of persistence, the population was extirpated in the 1960s, mainly as a result of over-harvest and habitat alterations. As there are four genetically distinct groups of Atlantic sturgeon inhabiting North American rivers today, we investigated the genetic provenance of the historic Baltic population by ancient DNA analyses using mitochondrial and nuclear markers. Results. The phylogeographic signal obtained from multilocus microsatellite DNA genotypes and mitochondrial DNA control region haplotypes, when compared to existing baseline datasets from extant populations, allowed for the identification of the region-of-origin of the North American Atlantic sturgeon founders. Moreover, statistical and simulation analyses of the multilocus genotypes allowed for the calculation of the effective number of individuals that originally founded the European population of Atlantic sturgeon. Our findings suggest that the Baltic population of A. oxyrinchus descended from a relatively small number of founders originating from the northern extent of the species' range in North America. Conclusion. These results demonstrate that the most northerly distributed North American A. oxyrinchus colonized the Baltic Sea ???1,200 years ago, suggesting that Canadian specimens should be the primary source of broodstock used for restoration in Baltic rivers. This study illustrates the great potential of patterns obtained from ancient DNA to identify population-of-origin to investigate historic genotype structure of extinct populations. ?? 2008 Ludwig et al; licensee BioMed Central Ltd.
TCF7L2 polymorphism, weight loss and proinsulin:insulin ratio in the diabetes prevention program.
McCaffery, Jeanne M; Jablonski, Kathleen A; Franks, Paul W; Dagogo-Jack, Sam; Wing, Rena R; Knowler, William C; Delahanty, Linda; Dabelea, Dana; Hamman, Richard; Shuldiner, Alan R; Florez, Jose C
2011-01-01
TCF7L2 variants have been associated with type 2 diabetes, body mass index (BMI), and deficits in proinsulin processing and insulin secretion. Here we sought to test whether these effects were apparent in high-risk individuals and modify treatment responses. We examined the potential role of the TCF7L2 rs7903146 variant in predicting resistance to weight loss or a lack of improvement of proinsulin processing during 2.5-years of follow-up participants (N = 2,994) from the Diabetes Prevention Program (DPP), a randomized controlled trial designed to prevent or delay diabetes in high-risk adults. We observed no difference in the degree of weight loss by rs7903146 genotypes. However, the T allele (conferring higher risk of diabetes) at rs7903146 was associated with higher fasting proinsulin at baseline (P<0.001), higher baseline proinsulin:insulin ratio (p<0.0001) and increased proinsulin:insulin ratio over a median of 2.5 years of follow-up (P = 0.003). Effects were comparable across treatment arms. The combination of a lack of impact of the TCF7L2 genotypes on the ability to lose weight, but the presence of a consistent effect on the proinsulin:insulin ratio over the course of DPP, suggests that high-risk genotype carriers at this locus can successfully lose weight to counter diabetes risk despite persistent deficits in insulin production.
Samet, A; Sledzińska, A; Krawczyk, B; Hellmann, A; Nowicki, S; Kur, J; Nowicki, B
2013-11-01
In patients with leukemia, the portal(s) and reasons for the persistence of an Escherichia coli recurrent bacteremia remain unclear. Adult Hematology Clinic (AHC) databases at the State Clinical Hospital in Gdańsk were reviewed to evaluate the frequency of E. coli bacteremia between 2002 and 2005. Blood and bowel E. coli strains were obtained and the genetic relatedness of the strains was analyzed. The rate of E. coli bacteremia per 1,000 admissions at the AHC was higher (85.0) than in the other clinics of the hospital (2.9), p < 0.001. A higher mortality was observed in patients with a history of E. coli versus non-E. coli bacteremia [30/95 (31 %) vs. 53/430 (12 %), p < 0.001]; 72.8 % of patients with leukemia had an unknown source of bacteremia. In 2005, 6 out of 25 (24 %) patients with leukemia had ≥2 episodes of E. coli-positive blood cultures. These gastrointestinal E. coli isolates were replaced within 3-8 weeks with a new E. coli H genotype. A recurrent episode of bacteremia was usually caused by an infection with a transient E. coli H genotype identical to that found in the subject's bowel. Consistent with the definition of bowel/blood translocation, the bowel appeared to be a portal for E. coli in these subjects and, hence, a clear source for their recurring bacteremia.
Foster, Nicola L.; Baums, Iliana B.; Sanchez, Juan A.; Paris, Claire B.; Chollett, Iliana; Agudelo, Claudia L.; Vermeij, Mark J. A.; Mumby, Peter J.
2013-01-01
K-selected species with low rates of sexual recruitment may utilise storage effects where low adult mortality allows a number of individuals to persist through time until a favourable recruitment period occurs. Alternative methods of recruitment may become increasingly important for such species if the availability of favourable conditions for sexual recruitment decline under rising anthropogenic disturbance and climate change. Here, we test the hypotheses that asexual dispersal is an integral life history strategy not only in branching corals, as previously reported, but also in a columnar, ‘K-selected’ coral species, and that its prevalence is driven by the frequency of severe hurricane disturbance. Montastraea annularis is a long-lived major frame-work builder of Caribbean coral reefs but its survival is threatened by the consequences of climate induced disturbance, such as bleaching, ocean acidification and increased prevalence of disease. 700 M. annularis samples from 18 reefs within the Caribbean were genotyped using six polymorphic microsatellite loci. We demonstrate that asexual reproduction occurs at varying frequency across the species-range and significantly contributes to the local abundance of M. annularis, with its contribution increasing in areas with greater hurricane frequency. We tested several competing hypotheses that might explain the observed pattern of genotypic diversity. 64% of the variation in genotypic diversity among the sites was explained by hurricane incidence and reef slope, demonstrating that large-scale disturbances combine with local habitat characteristics to shape the balance between sexual and asexual reproduction in populations of M. annularis. PMID:23308185
Bae, In-Gyu; Federspiel, Jerome J; Miró, José M; Woods, Christopher W; Park, Lawrence; Rybak, Michael J; Rude, Thomas H; Bradley, Suzanne; Bukovski, Suzana; de la Maria, Cristina Garcia; Kanj, Souha S; Korman, Tony M; Marco, Francesc; Murdoch, David R; Plesiat, Patrick; Rodriguez-Creixems, Marta; Reinbott, Porl; Steed, Lisa; Tattevin, Pierre; Tripodi, Marie-Françoise; Newton, Karly L; Corey, G Ralph; Fowler, Vance G
2009-11-01
The significance of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) is unknown. Using a multinational collection of isolates from methicillin-resistant S. aureus (MRSA) infective endocarditis (IE), we characterized patients with IE with and without hVISA, and we genotyped the infecting strains. MRSA bloodstream isolates from 65 patients with definite IE from 8 countries underwent polymerase chain reaction (PCR) for 31 virulence genes, pulsed-field gel electrophoresis, and multilocus sequence typing. hVISA was defined using population analysis profiling. Nineteen (29.2%) of 65 MRSA IE isolates exhibited the hVISA phenotype by population analysis profiling. Isolates from Oceania and Europe were more likely to exhibit the hVISA phenotype than isolates from the United States (77.8% and 35.0% vs 13.9%; P < .001). The prevalence of hVISA was higher among isolates with a vancomycin minimum inhibitory concentration of 2 mg/L (P = .026). hVISA-infected patients were more likely to have persistent bacteremia (68.4% vs 37.0%; P = .029) and heart failure (47.4% vs 19.6%; P = .033). Mortality did not differ between hVISA- and non-hVISA-infected patients (42.1% vs 34.8%, P = .586). hVISA and non-hVISA isolates were genotypically similar. In these analyses, the hVISA phenotype occurred in more than one-quarter of MRSA IE isolates, was associated with certain IE complications, and varied in frequency by geographic region.
Fernández-Hidalgo, N; Ribera, A; Larrosa, M N; Viedma, E; Origüen, J; de Alarcón, A; Fariñas, M C; Sáez, C; Peña, C; Múñez, E; García López, M V; Gavaldà, J; Pérez-Montarelo, D; Chaves, F; Almirante, B
2017-12-18
We aimed to evaluate the impact of Staphylococcus aureus phenotype (vancomycin MIC) and genotype (agr group, clonal complex CC) on the prognosis and clinical characteristics of infective endocarditis (IE). We performed a multicentre, longitudinal, prospective, observational study (June 2013 to March 2016) in 15 Spanish hospitals. Two hundred and thirteen consecutive adults (≥18 years) with a definite diagnosis of S. aureus IE were included. Primary outcome was death during hospital stay. Main secondary end points were persistent bacteraemia, sepsis/septic shock, peripheral embolism and osteoarticular involvement. Overall in-hospital mortality was 37% (n = 72). Independent risk factors for death were age-adjusted Charlson co-morbidity index (OR 1.20; 95% CI 1.08-1.34), congestive heart failure (OR 3.60; 95% CI 1.72-7.50), symptomatic central nervous system complication (OR 3.17; 95% CI 1.41-7.11) and severe sepsis/septic shock (OR 4.41; 95% CI 2.18-8.96). In the subgroup of methicillin-susceptible S. aureus IE (n = 173), independent risk factors for death were the age-adjusted Charlson co-morbidity index (OR 1.17; 95% CI 1.03-1.31), congestive heart failure (OR 3.39; 95% CI 1.51-7.64), new conduction abnormality (OR 4.42; 95% CI 1.27-15.34), severe sepsis/septic shock (OR 5.76; 95% CI 2.57-12.89) and agr group III (OR 0.27; 0.10-0.75). Vancomycin MIC ≥1.5 mg/L was not independently associated with death during hospital nor was it related to secondary end points. No other genotype variables were independently associated with in-hospital death. This is the first prospective study to assess the impact of S. aureus phenotype and genotype. Phenotype and genotype provided no additional predictive value beyond conventional clinical characteristics. No evidence was found to justify therapeutic decisions based on vancomycin MIC for either methicillin-resistant or methicillin-susceptible S. aureus. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Carskadon, Mary A; Sharkey, Katherine M; Knopik, Valerie S; McGeary, John E
2012-06-01
This study examined whether the 5-HTTLPR polymorphism in the SLC6A4 gene is associated with self-reported symptoms of depressed mood in first-year university students with a persistent pattern of short sleep. Students provided DNA samples and completed on-line sleep diaries and a mood scale during the first semester. A priori phenotypes for nocturnal sleep and mood scores were compared for the distribution of genotypes. Brown University, Providence, Rhode Island. A sample of 135 first-year students, 54 male, 71 Caucasian, mean age 18.1 (± 0.5) yr. None. Students completed on-line sleep diaries daily across the first term (21-64 days; mean = 51 days ± 11) and Center for Epidemiologic Studies-Depression (CES-D) mood scale after 8 wk. DNA was genotyped for the triallelic 5-HTTLPR polymorphism. Low-expressing S and L(G)polymorphisms were designated S', and high-expressing L(A) was designated L'. Phenotype groups were identified from a combination of CES-D (median split: high > 12; low < 13) and mean nocturnal total sleep time (TST) from diaries: (shorter ≤ 7 hr; longer ≥ 7.5 hr). Three genotypes were identified (S'S', S'L', L'L'); the S'S' genotype was present in a higher proportion of Asian than non-Asian students. FOUR PHENOTYPE GROUPS WERE COMPARED: 40 students with shorter TST/high CES-D; 34 with shorter TST/low CES-D; 29 with longer TST/high CES-D; 32 with longer TST/low CES-D. Female:male distribution did not vary across phenotype groups (chi-square = 1.39; df = 3; P = 0.71). S'S' participants (n = 23) were overrepresented in the shorter TST/high CES-D group (chi- square = 15.04; df = 6; P < 0.02). This association was sustained after removing participants with preexisting evidence of depressed mood (chi-square = 12.90; df = 6; P = 0.045). These data indicate that young adults who reported shorter nocturnal sleep and higher depressed mood are more likely than others to carry a variant of the SLC6A4 gene associated with low expression of the serotonin transporter.
Bar-Zeev, Naor; Jere, Khuzwayo C.; Bennett, Aisleen; Pollock, Louisa; Tate, Jacqueline E.; Nakagomi, Osamu; Iturriza-Gomara, Miren; Costello, Anthony; Mwansambo, Charles; Parashar, Umesh D.; Heyderman, Robert S.; French, Neil; Cunliffe, Nigel A.
2016-01-01
Background. Rotavirus vaccines have been introduced in many low-income African countries including Malawi in 2012. Despite early evidence of vaccine impact, determining persistence of protection beyond infancy, the utility of the vaccine against specific rotavirus genotypes, and effectiveness in vulnerable subgroups is important. Methods. We compared rotavirus prevalence in diarrheal stool and hospitalization incidence before and following rotavirus vaccine introduction in Malawi. Using case-control analysis, we derived vaccine effectiveness (VE) in the second year of life and for human immunodeficiency virus (HIV)–exposed and stunted children. Results. Rotavirus prevalence declined concurrent with increasing vaccine coverage, and in 2015 was 24% compared with prevaccine mean baseline in 1997–2011 of 32%. Since vaccine introduction, population rotavirus hospitalization incidence declined in infants by 54.2% (95% confidence interval [CI], 32.8–68.8), but did not fall in older children. Comparing 241 rotavirus cases with 692 test-negative controls, VE was 70.6% (95% CI, 33.6%–87.0%) and 31.7% (95% CI, −140.6% to 80.6%) in the first and second year of life, respectively, whereas mean age of rotavirus cases increased from 9.3 to 11.8 months. Despite higher VE against G1P[8] than against other genotypes, no resurgence of nonvaccine genotypes has occurred. VE did not differ significantly by nutritional status (78.1% [95% CI, 5.6%–94.9%] in 257 well-nourished and 27.8% [95% CI, −99.5% to 73.9%] in 205 stunted children; P = .12), or by HIV exposure (60.5% [95% CI, 13.3%–82.0%] in 745 HIV-unexposed and 42.2% [95% CI, −106.9% to 83.8%] in 174 exposed children; P = .91). Conclusions. Rotavirus vaccination in Malawi has resulted in reductions in disease burden in infants <12 months, but not in older children. Despite differences in genotype-specific VE, no genotype has emerged to suggest vaccine escape. VE was not demonstrably affected by HIV exposure or stunting. PMID:27059359
Coexistence of three specialist aphids on common milkweed, Asclepias syriaca.
Smith, R A; Mooney, K A; Agrawal, A A
2008-08-01
Coexistence of host-specific herbivores on plants is believed to be governed by interspecific interactions, but few empirical studies have systematically unraveled these dynamics. We investigated the role of several factors in promoting coexistence among the aphids Aphis nerii, Aphis asclepiadis, and Myzocallis asclepiadis that all specialize on common milkweed (Asclepias syriaca). Competitive exclusion is thought to occur when interspecific competition is stronger than intraspecific competition. Consequently, we investigated whether predators, mutualists, or resource quality affected the strength of intra- vs. interspecific competition among aphids in factorial manipulations of competition with exposure to predation, ants, and variable plant genotypes in three separate experiments. In the predation x competition experiment, predators reduced aphid per capita growth by 66%, but the strength of intra- and interspecific competition did not depend on predators. In the ants x competition experiment, ants reduced per capita growth of A. nerii and M. asclepiadis (neither of which were mutualists with ants) by approximately one-half. In so doing, ants ameliorated the negative effects of these competitors on ant-tended A. asclepiadis by two-thirds, representing a novel benefit of ant-aphid mutualism. Nevertheless, ants alone did not explain the persistence of competitively inferior A. asclepiadis as, even in the presence of ants, interspecific competition remained stronger than intraspecific competition. In the plant genotype x competition experiment, both A. asclepiadis and M. asclepiadis were competitively inferior to A. nerii, with the strength of interspecific competition exceeding that of intraspecific competition by 83% and 23%, respectively. Yet these effects differed among milkweed genotypes, and there were one or more plant genotypes for each aphid species where coexistence was predicted. A synthesis of our results shows that predators play little or no role in preferentially suppressing competitively dominant A. nerii. Nonetheless, A. asclepiadis benefits from ants, and A. asclepiadis and M. asclepiadis may escape competitive exclusion by A. nerii on select milkweed genotypes. Taken as a whole, the coexistence of three host-specific aphid species sharing the same resource was promoted by the dual action of ants as antagonists and mutualists and by genetic diversity in the plant population itself.
Bar-Zeev, Naor; Jere, Khuzwayo C; Bennett, Aisleen; Pollock, Louisa; Tate, Jacqueline E; Nakagomi, Osamu; Iturriza-Gomara, Miren; Costello, Anthony; Mwansambo, Charles; Parashar, Umesh D; Heyderman, Robert S; French, Neil; Cunliffe, Nigel A
2016-05-01
Rotavirus vaccines have been introduced in many low-income African countries including Malawi in 2012. Despite early evidence of vaccine impact, determining persistence of protection beyond infancy, the utility of the vaccine against specific rotavirus genotypes, and effectiveness in vulnerable subgroups is important. We compared rotavirus prevalence in diarrheal stool and hospitalization incidence before and following rotavirus vaccine introduction in Malawi. Using case-control analysis, we derived vaccine effectiveness (VE) in the second year of life and for human immunodeficiency virus (HIV)-exposed and stunted children. Rotavirus prevalence declined concurrent with increasing vaccine coverage, and in 2015 was 24% compared with prevaccine mean baseline in 1997-2011 of 32%. Since vaccine introduction, population rotavirus hospitalization incidence declined in infants by 54.2% (95% confidence interval [CI], 32.8-68.8), but did not fall in older children. Comparing 241 rotavirus cases with 692 test-negative controls, VE was 70.6% (95% CI, 33.6%-87.0%) and 31.7% (95% CI, -140.6% to 80.6%) in the first and second year of life, respectively, whereas mean age of rotavirus cases increased from 9.3 to 11.8 months. Despite higher VE against G1P[8] than against other genotypes, no resurgence of nonvaccine genotypes has occurred. VE did not differ significantly by nutritional status (78.1% [95% CI, 5.6%-94.9%] in 257 well-nourished and 27.8% [95% CI, -99.5% to 73.9%] in 205 stunted children;P= .12), or by HIV exposure (60.5% [95% CI, 13.3%-82.0%] in 745 HIV-unexposed and 42.2% [95% CI, -106.9% to 83.8%] in 174 exposed children;P= .91). Rotavirus vaccination in Malawi has resulted in reductions in disease burden in infants <12 months, but not in older children. Despite differences in genotype-specific VE, no genotype has emerged to suggest vaccine escape. VE was not demonstrably affected by HIV exposure or stunting. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.
Sarkar, Neelakshi; Pal, Ananya; Das, Dipanwita; Saha, Debraj; Biswas, Avik; Bandopadhayay, Bhaswati; Chakraborti, Mandira; Ghosh, Mrinmoy; Chakravarty, Runu
2015-01-01
Hepatitis B Virus (HBV) manifests high genetic variability and is classifiable into ten genotypes (A-J). HBV infection can lead to variable clinical outcomes, ranging from self-limiting acute hepatitis to active chronic hepatitis, cirrhosis and hepatocellular carcinoma. The present study characterizes HBV strains circulating among patients with acute (AHB) and chronic HBV infection (CHB). Among a total of 653 HBsAg positive cases, 40 manifested acute infection. After sequencing the surface(S), basal core promoter/pre-core(BCP/PC) and the X gene regions, phylogenetic tree was constructed using MEGA4 by neighbor-joining method. Statistical robustness was established with bootstrap analysis. Nucleotide diversity was determined by Shannon entropy per site using the Entropy program of the Los Alamos National Laboratories. Analyses of acute patients revealed that HBV/D2 is the major circulating sub-genotype and commonly associated with sexual promiscuity and the age group between15-30 years. Comparison of AHB and CHB patients revealed that HBeAg positivity, ALT levels and genotype D were significantly high in AHB, whereas CHB patients were predominantly male, had a high viral load, and were commonly associated with genotype C. The frequencies of mutations in the S, BCP/PC, and X gene were low in AHB as compared to CHB. Drug resistant mutations were not detectable in the polymerase gene of AHB. Average nucleotide diversity in AHB was considerably low as compared to CHB. Further, the highest average ΔH (average difference in entropy between chronic and acute infection) was observed in the BCP/PC region implying that this region was most vulnerable to mutations upon HBV persistence, especially in case of genotype C. Additionally, among all substitutions, the A1762T and G1764A BCP mutations were the strongest indicators of chronicity. In conclusion, the study exhibits a general portrait of HBV strains circulating among acute hepatitis B patients in Eastern India and their intricate differences with chronic patients which should be useful from the clinical point of view.
2018-01-01
ABSTRACT Primary infection with human cytomegalovirus (HCMV) results in a lifelong infection due to its ability to establish latent infection, with one characterized viral reservoir being hematopoietic cells. Although reactivation from latency causes serious disease in immunocompromised individuals, our molecular understanding of latency is limited. Here, we delineate viral gene expression during natural HCMV persistent infection by analyzing the massive transcriptome RNA sequencing (RNA-seq) atlas generated by the Genotype-Tissue Expression (GTEx) project. This systematic analysis reveals that HCMV persistence in vivo is prevalent in diverse tissues. Notably, we find only viral transcripts that resemble gene expression during various stages of lytic infection with no evidence of any highly restricted latency-associated viral gene expression program. To further define the transcriptional landscape during HCMV latent infection, we also used single-cell RNA-seq and a tractable experimental latency model. In contrast to some current views on latency, we also find no evidence for any highly restricted latency-associated viral gene expression program. Instead, we reveal that latency-associated gene expression largely mirrors a late lytic viral program, albeit at much lower levels of expression. Overall, our work has the potential to revolutionize our understanding of HCMV persistence and suggests that latency is governed mainly by quantitative changes, with a limited number of qualitative changes, in viral gene expression. PMID:29535194
Antibiotic tolerance and the alternative lifestyles of Staphylococcus aureus.
Bui, Long M G; Conlon, Brian P; Kidd, Stephen P
2017-02-28
Staphylococcus aureus has an incredible ability to survive, either by adapting to environmental conditions or defending against exogenous stress. Although there are certainly important genetic traits, in part this ability is provided by the breadth of modes of growth S. aureus can adopt. It has been proposed that while within their host, S. aureus survives host-generated and therapeutic antimicrobial stress via alternative lifestyles: a persister sub-population, through biofilm growth on host tissue or by growing as small colony variants (SCVs). Key to an understanding of chronic and relapsing S. aureus infections is determining the molecular basis for its switch to these quasi-dormant lifestyles. In a multicellular biofilm, the metabolically quiescent bacterial community additionally produces a highly protective extracellular polymeric substance (EPS). Furthermore, there are bacteria within a biofilm community that have an altered physiology potentially equivalent to persister cells. Recent studies have directly linked the cellular ATP production by persister cells as their key feature and the basis for their tolerance of a range of antibiotics. In clinical settings, SCVs of S. aureus have been observed for many years; when cultured, these cells form non-pigmented colonies and are approximately ten times smaller than their counterparts. Various genotypic factors have been identified in attempts to characterize S. aureus SCVs and different environmental stresses have been implicated as important inducers. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.
First genealogy for a wild marine fish population reveals multigenerational philopatry.
Salles, Océane C; Pujol, Benoit; Maynard, Jeffrey A; Almany, Glenn R; Berumen, Michael L; Jones, Geoffrey P; Saenz-Agudelo, Pablo; Srinivasan, Maya; Thorrold, Simon R; Planes, Serge
2016-11-15
Natal philopatry, the return of individuals to their natal area for reproduction, has advantages and disadvantages for animal populations. Natal philopatry may generate local genetic adaptation, but it may also increase the probability of inbreeding that can compromise persistence. Although natal philopatry is well documented in anadromous fishes, marine fish may also return to their birth site to spawn. How philopatry shapes wild fish populations is, however, unclear because it requires constructing multigenerational pedigrees that are currently lacking for marine fishes. Here we present the first multigenerational pedigree for a marine fish population by repeatedly genotyping all individuals in a population of the orange clownfish (Amphiprion percula) at Kimbe Island (Papua New Guinea) during a 10-y period. Based on 2927 individuals, our pedigree analysis revealed that longitudinal philopatry was recurrent over five generations. Progeny tended to settle close to their parents, with related individuals often sharing the same colony. However, successful inbreeding was rare, and genetic diversity remained high, suggesting occasional inbreeding does not impair local population persistence. Local reproductive success was dependent on the habitat larvae settled into, rather than the habitat they came from. Our study suggests that longitudinal philopatry can influence both population replenishment and local adaptation of marine fishes. Resolving multigenerational pedigrees during a relatively short period, as we present here, provides a framework for assessing the ability of marine populations to persist and adapt to accelerating climate change.
First genealogy for a wild marine fish population reveals multigenerational philopatry
Salles, Océane C.; Pujol, Benoit; Maynard, Jeffrey A.; Almany, Glenn R.; Berumen, Michael L.; Jones, Geoffrey P.; Saenz-Agudelo, Pablo; Srinivasan, Maya; Thorrold, Simon R.; Planes, Serge
2016-01-01
Natal philopatry, the return of individuals to their natal area for reproduction, has advantages and disadvantages for animal populations. Natal philopatry may generate local genetic adaptation, but it may also increase the probability of inbreeding that can compromise persistence. Although natal philopatry is well documented in anadromous fishes, marine fish may also return to their birth site to spawn. How philopatry shapes wild fish populations is, however, unclear because it requires constructing multigenerational pedigrees that are currently lacking for marine fishes. Here we present the first multigenerational pedigree for a marine fish population by repeatedly genotyping all individuals in a population of the orange clownfish (Amphiprion percula) at Kimbe Island (Papua New Guinea) during a 10-y period. Based on 2927 individuals, our pedigree analysis revealed that longitudinal philopatry was recurrent over five generations. Progeny tended to settle close to their parents, with related individuals often sharing the same colony. However, successful inbreeding was rare, and genetic diversity remained high, suggesting occasional inbreeding does not impair local population persistence. Local reproductive success was dependent on the habitat larvae settled into, rather than the habitat they came from. Our study suggests that longitudinal philopatry can influence both population replenishment and local adaptation of marine fishes. Resolving multigenerational pedigrees during a relatively short period, as we present here, provides a framework for assessing the ability of marine populations to persist and adapt to accelerating climate change. PMID:27799530
Genetic Variability of Smoking Persistence in African Americans
Hamidovic, A; Kasberger, J; Young, T; Goodloe, R; Redline, S; Buxbaum, S; Benowitz, N; Bergen, A; Butler, K; Franceschini, N; Gharib, S; Hitsman, B; Levy, D; Meng, Y; Papanicolaou, G; Preiss, S; Spring, B; Styn, M; Tong, E; White, W; Wiggins, K; Jorgenson, E
2011-01-01
To date, most genetic association analyses of smoking behaviors have been conducted in populations of European ancestry and many of these studies focused on the phenotype that measures smoking quantity, i.e. cigarettes per day. Additional association studies in diverse populations with different linkage disequilibrium (LD) patterns and an alternate phenotype, such as total tobacco exposure which accounts for intermittent periods of smoking cessation within a larger smoking period as measured in large cardiovascular risk studies, can aid the search for variants relevant to smoking behavior. For these reasons, we undertook an association analysis using a genotyping array that includes 2100 genes to analyze smoking persistence in unrelated African-American participants from The Atherosclerosis Risk in Communities (ARIC) study. A locus located ~ 4 Kb downstream from the 3’ UTR of the Brain-Derived Neurotrophic Factor (BDNF) significantly influenced smoking persistence. In addition, independent variants rs12915366 and rs12914385 in the cluster of genes encoding nicotinic acetylcholine receptor subunits (CHRNA5-CHRNA3-CHRNB4) on 15q25.1 were also associated with the phenotype in this sample of African American subjects. To our knowledge, this is the first study to more extensively evaluate the genome in the African American population as a limited number of previous studies of smoking behavior in this population included evaluations of only single genomic regions. PMID:21436384
Persistent Mullerian duct syndrome with transverse testicular ectopia and seminoma.
Alp, Bilal Fırat; Demirer, Zafer; Gürağaç, Ali; Babacan, Oğuzhan; Sarı, Erkan; Sarı, Sebahattin; Yavan, Ibrahim
2014-08-01
Persistent Mullerian duct syndrome (PMDS) is a rare form of the 46 XY disorders of sexual differentiation, characterized by the presence of a uterus and fallopian tubes due to the failure of Mullerian duct regression in genotypically normal males. More than 150 cases have been recorded, most of them in adults. In most cases, the PMDS is discovered during surgery for inguinal hernia or cryptorchidism, or by the presence of transverse testicular ectopia (TTE). The presence of PMDS with TTE is even more uncommon. In TTE, both testes descend through the same inguinal canal into the same scrotal sac. Patients with TTE present with symptoms of unilateral cryptorchidism and a contralateral inguinal hernia. For patients with inguinal hernia and cryptorchidism associated with TTE, PMDS should be kept in mind, and radiologic evaluation such as ultrasonography or magnetic resonance imaging of the genitourinary system and karyotyping are recommended. Whereas radiologic evaluation could be helpful in the diagnosis of TTE, it cannot diagnose the malignancy itself. The case explained in this report will offer urologists additional useful treatment strategies for patients with inguinal hernia and cryptorchidism.
Resistance to thermal stress in corals without changes in symbiont composition
Bellantuono, Anthony J.; Hoegh-Guldberg, Ove; Rodriguez-Lanetty, Mauricio
2012-01-01
Discovering how corals can adjust their thermal sensitivity in the context of global climate change is important in understanding the long-term persistence of coral reefs. In this study, we showed that short-term preconditioning to higher temperatures, 3°C below the experimentally determined bleaching threshold, for a period of 10 days provides thermal tolerance for the symbiosis stability between the scleractinian coral, Acropora millepora and Symbiodinium. Based on genotypic analysis, our results indicate that the acclimatization of this coral species to thermal stress does not come down to simple changes in Symbiodinium and/or the bacterial communities that associate with reef-building corals. This suggests that the physiological plasticity of the host and/or symbiotic components appears to play an important role in responding to ocean warming. The further study of host and symbiont physiology, both of Symbiodinium and prokaryotes, is of paramount importance in the context of global climate change, as mechanisms for rapid holobiont acclimatization will become increasingly important to the long-standing persistence of coral reefs. PMID:21976690
Nyitray, Alan G; Carvalho da Silva, Roberto J; Chang, Mihyun; Baggio, Maria Luiza; Ingles, Donna J; Abrahamsen, Martha; Papenfuss, Mary; Lin, Hui-Yi; Salmerón, Jorge; Quiterio, Manuel; Lazcano-Ponce, Eduardo; Villa, Luisa L; Giuliano, Anna R
2016-06-01
Given high rates of anal disease, we investigated the natural history of high-risk anal human papillomavirus (HPV) among a multinational group of men who have sex with men (MSM) aged 18-64 years. Anal specimens from human immunodeficiency virus-negative men from Brazil, Mexico, and the United States were genotyped. Over 2 years, 406 MSM provided evaluable specimens every 6 months for ≥2 visits. These men were stratified into men who have sex only with men (MSOM, n = 70) and men who have sex with women and men (MSWM, n = 336). Persistence was defined as ≥12 months' type-specific duration and could begin with either a prevalent or incident infection. Prevalence ratios and 95% confidence intervals were calculated by Poisson regression. Median follow-up time was 2.1 years. Retention was 82%. Annual cumulative incidence of 9-valent vaccine types was 19% and 8% among MSOM and MSWM, respectively (log-rank P = .02). Duration of anal HPV did not differ for MSOM and MSWM and was a median of 6.9 months for HPV-16 after combining men from the 2 groups. Among men with prevalent high-risk infection (n = 106), a total of 36.8%, retained the infection for at least 24 months. For those with prevalent HPV-16 (n = 27), 29.6% were persistent for at least 24 months. Persistence of high-risk HPV was associated with number of male anal sex partners and inversely associated with number of female sex partners. MSM with prevalent high-risk HPV infection should be considered at increased risk for nontransient infection. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.
Kolver, E S; Roche, J R; Burke, C R; Kay, J K; Aspin, P W
2007-12-01
The aim of this study was to test the feasibility of extended lactations in pastoral systems by using divergent dairy cow genotypes [New Zealand (NZ) or North American (NA) Holstein-Friesian (HF)] and levels of nutrition (0, 3, or 6 kg/d of concentrate dry matter). Mean calving date was July 28, 2003, and all cows were dried off by May 6, 2005. Of the 56 cows studied, 52 (93%) were milking at 500 d in milk (DIM) and 10 (18%) were milking at 650 DIM. Dietary treatments did not affect DIM (605 +/- 8.3; mean +/- SEM). Genotype by diet interactions were found for total yield of milk, protein, and milk solids (fat + protein), expressed per cow and as a percentage of body weight. Differences between genotypes were greatest at the highest level of supplementation. Compared with NZ HF, NA HF produced 35% more milk, 24% more milk fat, 25% more milk protein, and at drying off had 1.9 units less body condition score (1 to 10 scale). Annualized milk solids production, defined as production achieved during the 24-mo calving interval divided by 2 yr, was 79% of that produced in a normal 12-mo calving interval by NZ HF, compared with 94% for NA HF. Compared with NZ HF, NA HF had a similar 21-d submission rate (85%) to artificial insemination, a lower 42-d pregnancy rate (56 vs. 79%), and a higher final nonpregnancy rate (30 vs. 3%) when mated at 451 d after calving. These results show that productive lactations of up to 650 d are possible on a range of pasture-based diets, with the highest milk yields produced by NA HF supplemented with concentrates. Based on the genetics represented, milking cows for 2 yr consecutively, with calving and mating occurring every second year, may exploit the superior lactation persistency of high-yielding cows while improving reproductive performance.
Dill, Alisa; Letra, Ariadne; Chaves de Souza, Letícia; Yadlapati, Mamatha; Biguetti, Claudia Cristina; Garlet, Gustavo Pompermaier; Vieira, Alexandre R; Silva, Renato Menezes
2015-02-01
It has been proposed that individual genetic predisposition may contribute to persistent apical periodontitis. Cytokines are associated with levels of inflammation and are involved in caries, pulpal, and periapical tissue destruction. We hypothesized that polymorphisms in cytokine genes may contribute to an individual's increased susceptibility to apical tissue destruction in response to deep carious lesions. Subjects with deep carious lesions with or without periapical lesions (≥3 mm) were recruited at the University of Pittsburgh, Pittsburgh, PA, and the University of Texas at Houston, Houston, TX. Genomic DNA samples of 316 patients were sorted into 2 groups: 136 cases with deep carious lesions and periapical lesions (cases) and 180 cases with deep carious lesions but no periapical lesions (controls). Nine single-nucleotide polymorphisms in IL1B, IL6, TNF, RANK, RANKL, and OPG genes were selected for genotyping. Genotypes were generated by end point analysis using TaqMan chemistry (Invitrogen, Carlsbad, CA) in a real-time polymerase chain reaction instrument. Allele and genotype frequencies were compared among cases and controls using the PLINK program (http://pngu.mgh.harvard.edu/purcell/plink/). Ninety-three human periapical granulomas and 24 healthy periodontal ligament tissues collected postoperatively were used for messenger RNA expression analyses of IL1B. A single-nucleotide polymorphism in IL1B (rs1143643) showed allelic (P = .02) and genotypic (P = .004) association with cases of deep caries and periapical lesions. We also observed altered transmission of IL1B marker haplotypes (P = .02) in these individuals. IL1B was highly expressed in granulomas (P < .001). Variations in IL1B may be associated with periapical lesion formation in individuals with untreated deep carious lesions. Future studies could help predict host susceptibility to developing periapical lesions. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Abu Zeid, Walaa M; Ramadan, Dalia I; Shemis, Mohamed A
2016-03-01
Mutations within the major hydrophilic region (MHR) of the hepatitis B surface antigen (HBsAg) have been reported in relation to viral persistence by evasion from vaccine and immunotherapy, severity of liver disease and lack of detection by commercial kits. The aim of this study was to elucidate the circulation of hepatitis B virus (HBV) genotypes, subgenotypes and serotypes in Egypt, with recognition of the pattern and prevalence of MHR mutations possibly occurring during the course of the disease. Eighty-eight samples from patients with chronic HBV infection were included in the study. The surface protein-encoding gene (S gene) in the HBV genome was subjected to amplification and partial sequencing. Based on phylogenetic analysis, only genotype D was found circulating among patients. The majority of isolates belonged to subgenotype D3 (86.3%), followed by D7 (8%), then D5 (3.4%) and lastly D1 (2.3%). Two subtypes were identified: ayw2 (97%) and ayw3 (2%). The 'w' sub-determinant was not defined in one isolate (1%). A significant proportion of patients (13/88, 14.8%) exhibited mutations in the MHR, 10 of whom harboured mutations in the 'a' determinant region and three outside. The first loop comprised four patients with three mutations (P127S, P127T and Y134F). The second loop contained six patients, all with one mutation, S143L, which was most frequently encountered in this study (6.8%). We conclude that genotype D, subgenotype D3 and HBsAg subtype ayw2 are the most common types circulating in Egypt, which account for 100%, 86.3% and 97% of the population, respectively, with a moderate degree of MHR mutations. Copyright © 2016 Arab Journal of Gastroenterology. Published by Elsevier B.V. All rights reserved.
Sy, Sherwin K B; Heuberger, Jules; Shilbayeh, Sireen; Conrado, Daniela J; Derendorf, Hartmut
2013-10-01
The SNP A6986G of the CYP3A5 gene (*3) results in a non-functional protein due to a splicing defect whereas the C3435T was associated with variable expression of the ABCB1 gene, due to protein instability. Part of the large interindividual variability in tacrolimus efficacy and toxicity can be accounted for by these genetic factors. Seventy-two individuals were examined for A6986G and C3435T polymorphism using a PCR-RFLP-based technique to estimate genotype and allele frequencies in the Jordanian population. The association of age, hematocrit, platelet count, CYP3A5, and ABCB1 polymorphisms with tacrolimus dose- and body-weight-normalized levels in the subset of 38 pediatric renal transplant patients was evaluated. A Markov model was used to evaluate the time-dependent probability of an adverse event occurrence by CYP3A5 phenotypes and ABCB1 genotypes. The time-dependent probability of adverse event was about double in CYP3A5 non-expressors compared to the expressors for the first 12 months of therapy. The CYP3A5 non-expressors had higher corresponding normalized tacrolimus levels compared to the expressors in the first 3 months. The correlation trend between probability of adverse events and normalized tacrolimus concentrations for the two CYP3A5 phenotypes persisted for the first 9 months of therapy. The differences among ABCB1 genotypes in terms of adverse events and normalized tacrolimus levels were only observed in the first 3 months of therapy. The information on CYP3A5 genotypes and tacrolimus dose requirement is important in designing effective programs toward management of tacrolimus side effects particularly for the initial dose when tacrolimus blood levels are not available for therapeutic drug monitoring.
Bea, Jennifer W.; Lohman, Timothy G.; Cussler, Ellen C.; Going, Scott B.; Thompson, Patricia A.
2013-01-01
Genetic variations in the adrenergic receptor (ADR) have been associated with body composition in cross-sectional studies. Recent findings suggest that ADR variants may also modify body composition response to lifestyle. We assessed the role of ADR variants in body composition response to 12 months of resistance training versus control in previously sedentary postmenopausal women. Randomized trial completers were genotyped for A2BGlu9/12 by fragment length analysis, and B2Gln27Glu and B3Trp64Arg by TaqMan (n=148, 54% hormone therapy users). Associations between genotypes and body composition, by dual energy X-ray absorptiometry, were analyzed using univariate models. There was no main effect of individual genes on change in body composition, however, gene × exercise interactions were observed for A2BGlu9/12 and B2Gln27Glu on change in lean soft tissue (LST, p=0.02); exercisers on the A2BGlu9- background gained LST compared to a loss among controls over 12 months (p<0.05), with no significant intervention effect on the A2B Glu9+ background. Similarly, there was a significant LST gain with exercise on the B2Glu27+ background compared to loss among controls and no intervention effect on the B2Glu27- background. A non-significant association between total body fat (TBF) and B3Trp64Arg persisted among sedentary controls only when intervention groups were separated (%TBF gain with B3Arg 64+ carriage, p=0.03); exercisers lost TBF regardless of genotype. In summary, effect modification by lifestyle was demonstrated on ADR A2B, B2, and B3 genetic backgrounds. Individuals with certain ADR genotypes may be more vulnerable to adverse changes in body composition with sedentary behavior, thus these candidate genes warrant further study. PMID:20401689
Sivasailam, Asok; Sasidharan, Suchithra; Kollannur, Justin Davis; Syam, Radhika
2017-01-01
Dairy cows affected with subclinical mastitis can be sources of virulent, antimicrobial-resistant Staphylococci to humans because of the excretion of the bacteria through their milk. This study focussed on the phenotypic and genotypic antibiotic resistance patterns of Staphylococci isolated from dairy cows in early dry period. Among 96 isolates of Gram positive cocci from 157 cows, 76 were identified as Coagulase Negative Staphylococci and the remaining 20 were Staphylococcus aureus. Typical amplicons of coagulase gene were obtained for all 20 samples of S. aureus with three major coagulase types being identified as giving 627 bp (40%), 910 bp (35%) and 710 bp (25%) long PCR products. The groEL gene was amplified in PCR of all 76 isolates of Coagulase Negative Staphylococci, and incubation of PCR products with restriction enzyme PvuII yielded three distinct PCR-RFLP fragment patterns bearing resemblance to S. chromogenes and S. hyicus. Highest sensitivity of Coagulase Negative Staphylococci was noted for Azithromycin (92.5%) and the least to Tetracyclines (76.3%), whereas for S. aureus, it was Cefoperazone (95%) and Azithromycin (72.2%) respectively. Phenotypic resistance to Oxacillin (25 isolates), and Cefoxitin (11 isolates) was detected by dilution method with a commercial strip (Ezy MICTM). Genotypic resistance to β-Lactam antibiotics was found in 65 (34 with mecA gene and 31 with blaZ gene) isolates. Eighteen isolates possessed both the genes, with the PVL gene for virulence being detected in five of them. Nine isolates which had mecA gene were phenotypically susceptible to oxacillin while phenotypic resistance to oxacillin was observed in seven isolates that did not have either mecA or blaZ gene. This is the first report of persistent Staphylococcal infections possessing PVL gene and high level of genotypic resistance to β-Lactam antibiotics in small- holder dairy cattle from India. PMID:29091956
Dudley, Matthew Z; Sheen, Patricia; Gilman, Robert H; Ticona, Eduardo; Friedland, Jon S; Kirwan, Daniela E; Caviedes, Luz; Rodriguez, Richard; Cabrera, Lilia Z; Coronel, Jorge; Grandjean, Louis; Moore, David A J; Evans, Carlton A; Huaroto, Luz; Chávez-Pérez, Víctor; Zimic, Mirko
2016-12-07
Hospital infection control measures are crucial to tuberculosis (TB) control strategies within settings caring for human immunodeficiency virus (HIV)-positive patients, as these patients are at heightened risk of developing TB. Pyrazinamide (PZA) is a potent drug that effectively sterilizes persistent Mycobacterium tuberculosis bacilli. However, PZA resistance associated with mutations in the nicotinamidase/pyrazinamidase coding gene, pncA, is increasing. A total of 794 patient isolates obtained from four sites in Lima, Peru, underwent spoligotyping and drug resistance testing. In one of these sites, the HIV unit of Hospital Dos de Mayo (HDM), an isolation ward for HIV/TB coinfected patients opened during the study as an infection control intervention: circulating genotypes and drug resistance pre- and postintervention were compared. All other sites cared for HIV-negative outpatients: genotypes and drug resistance rates from these sites were compared with those from HDM. HDM patients showed high concordance between multidrug resistance, PZA resistance according to the Wayne method, the two most common genotypes (spoligotype international type [SIT] 42 of the Latino American-Mediterranean (LAM)-9 clade and SIT 53 of the T1 clade), and the two most common pncA mutations (G145A and A403C). These associations were absent among community isolates. The infection control intervention was associated with 58-92% reductions in TB caused by SIT 42 or SIT 53 genotypes (odds ratio [OR] = 0.420, P = 0.003); multidrug-resistant TB (OR = 0.349, P < 0.001); and PZA-resistant TB (OR = 0.076, P < 0.001). In conclusion, pncA mutation typing, with resistance testing and spoligotyping, was useful in identifying a nosocomial TB outbreak and demonstrating its resolution after implementation of infection control measures. © The American Society of Tropical Medicine and Hygiene.
Reynolds, Laura K; DuBois, Katherine; Abbott, Jessica M; Williams, Susan L; Stachowicz, John J
2016-01-01
Growing evidence shows that increasing global temperature causes population declines and latitudinal shifts in geographical distribution for plants living near their thermal limits. Yet, even populations living well within established thermal limits of a species may suffer as the frequency and intensity of warming events increase with climate change. Adaptive response to this stress at the population level depends on the presence of genetic variation in thermal tolerance in the populations in question, yet few data exist to evaluate this. In this study, we examined the immediate effects of a moderate warming event of 4.5°C lasting 5 weeks and the legacy effects after a 5 week recovery on different genotypes of the marine plant Zostera marina (eelgrass). We conducted the experiment in Bodega Bay, CA USA, where average summer water temperatures are 14-15°C, but extended warming periods of 17-18°C occur episodically. Experimental warming increased shoot production by 14% compared to controls held at ambient temperature. However, after returning temperature to ambient levels, we found strongly negative, delayed effects of warming on production: shoot production declined by 27% and total biomass decreased by 50% relative to individuals that had not been warmed. While all genotypes' production decreased in the recovery phase, genotypes that grew the most rapidly under benign thermal conditions (control) were the most susceptible to the detrimental effects of warming. This suggests a potential tradeoff in relative performance at normal vs. elevated temperatures. Modest short-term increases in water temperature have potentially prolonged negative effects within the species' thermal envelope, but genetic variation within these populations may allow for population persistence and adaptation. Further, intraspecific variation in phenology can result in maintenance of population diversity and lead to enhanced production in diverse stands given sufficient frequency of warming or other stress events.
Durigan, Mauricio; Abreu, Aluana Gonçalves; Zucchi, Maria Imaculada; Franco, Regina Maura Bueno; de Souza, Anete Pereira
2014-01-01
Background Giardia duodenalis is a flagellate protozoan that parasitizes humans and several other mammals. Protozoan contamination has been regularly documented at important environmental sites, although most of these studies were performed at the species level. There is a lack of studies that correlate environmental contamination and clinical infections in the same region. The aim of this study is to evaluate the genetic diversity of a set of clinical and environmental samples and to use the obtained data to characterize the genetic profile of the distribution of G. duodenalis and the potential for zoonotic transmission in a metropolitan region of Brazil. Methodology/Principal Findings The genetic assemblages and subtypes of G. duodenalis isolates obtained from hospitals, a veterinary clinic, a day-care center and important environmental sites were determined via multilocus sequence-based genotyping using three unlinked gene loci. Cysts of Giardia were detected at all of the environmental sites. Mixed assemblages were detected in 25% of the total samples, and an elevated number of haplotypes was identified. The main haplotypes were shared among the groups, and new subtypes were identified at all loci. Ten multilocus genotypes were identified: 7 for assemblage A and 3 for assemblage B. Conclusions/Significance There is persistent G. duodenalis contamination at important environmental sites in the city. The identified mixed assemblages likely represent mixed infections, suggesting high endemicity of Giardia in these hosts. Most Giardia isolates obtained in this study displayed zoonotic potential. The high degree of genetic diversity in the isolates obtained from both clinical and environmental samples suggests that multiple sources of infection are likely responsible for the detected contamination events. The finding that many multilocus genotypes (MLGs) and haplotypes are shared by different groups suggests that these sources of infection may be related and indicates that there is a notable risk of human infection caused by Giardia in this region. PMID:25536055
Genung, Mark A; Bailey, Joseph K; Schweitzer, Jennifer A
2013-01-01
Aboveground-belowground linkages are recognized as divers of community dynamics and ecosystem processes, but the impacts of plant-neighbor interactions on these linkages are virtually unknown. Plant-neighbor interactions are a type of interspecific indirect genetic effect (IIGE) if the focal plant's phenotype is altered by the expression of genes in a neighboring heterospecific plant, and IIGEs could persist after plant senescence to affect ecosystem processes. This perspective can provide insight into how plant-neighbor interactions affect evolution, as IIGEs are capable of altering species interactions and community composition over time. Utilizing genotypes of Solidago altissima and Solidago gigantea, we experimentally tested whether IIGEs that had affected living focal plants would affect litter decomposition rate, as well as nitrogen (N) and phosphorous (P) dynamics after the focal plant senesced. We found that species interactions affected N release and genotype interactions affected P immobilization. From a previous study we knew that neighbor genotype influenced patterns of biomass allocation for focal plants. Here we extend those previous results to show that these changes in biomass allocation altered litter quality, that then altered rates of decomposition and nutrient cycling. Our results provide insights into above- and belowground linkages by showing that, through their effects on plant litter quality (e.g., litter lignin:N), IIGEs can have afterlife effects, tying plant-neighbor interactions to ecosystem processes. This holistic approach advances our understanding of decomposition and nutrient cycling by showing that evolutionary processes (i.e., IIGEs) can influence ecosystem functioning after plant senescence. Because plant traits are determined by the combined effects of genetic and environmental influences, and because these traits are known to affect decomposition and nutrient cycling, we suggest that ecosystem processes can be described as gene-less products of genetic interactions among the species comprising ecological communities.
Genung, Mark A.; Bailey, Joseph K.; Schweitzer, Jennifer A.
2013-01-01
Aboveground-belowground linkages are recognized as divers of community dynamics and ecosystem processes, but the impacts of plant-neighbor interactions on these linkages are virtually unknown. Plant-neighbor interactions are a type of interspecific indirect genetic effect (IIGE) if the focal plant’s phenotype is altered by the expression of genes in a neighboring heterospecific plant, and IIGEs could persist after plant senescence to affect ecosystem processes. This perspective can provide insight into how plant-neighbor interactions affect evolution, as IIGEs are capable of altering species interactions and community composition over time. Utilizing genotypes of Solidago altissima and Solidago gigantea, we experimentally tested whether IIGEs that had affected living focal plants would affect litter decomposition rate, as well as nitrogen (N) and phosphorous (P) dynamics after the focal plant senesced. We found that species interactions affected N release and genotype interactions affected P immobilization. From a previous study we knew that neighbor genotype influenced patterns of biomass allocation for focal plants. Here we extend those previous results to show that these changes in biomass allocation altered litter quality, that then altered rates of decomposition and nutrient cycling. Our results provide insights into above- and belowground linkages by showing that, through their effects on plant litter quality (e.g., litter lignin:N), IIGEs can have afterlife effects, tying plant-neighbor interactions to ecosystem processes. This holistic approach advances our understanding of decomposition and nutrient cycling by showing that evolutionary processes (i.e., IIGEs) can influence ecosystem functioning after plant senescence. Because plant traits are determined by the combined effects of genetic and environmental influences, and because these traits are known to affect decomposition and nutrient cycling, we suggest that ecosystem processes can be described as gene-less products of genetic interactions among the species comprising ecological communities. PMID:23349735
Moudi, Bita; Heidari, Zahra; Mahmoudzadeh-Sagheb, Hamidreza; Hashemi, Mohammad; Metanat, Malihe; Khosravi, Soheila; Farrokh, Parisa
2016-02-01
IL-10 can play a vital role in immune response against HBV. Three biallelic SNPs from the transcription start site control the transcription of the IL-10 gene. An association between susceptibility to HBV and IL-10 polymorphisms has been suggested in patients with HBV infection. The present study was designed to study the association between polymorphisms in interleukin-10 (-1082 A/G, -819 T/C and -592 A/C) promoter gene and chronic hepatitis B virus (HBV) infection. 221 chronically infected patients and 200 healthy control subjects were enrolled in the study. Three biallelic (-1082 A/G, -819 T/C and -592 A/C) polymorphisms in the IL-10 promoter gene were determined by PCR-RFLP method. Persistent HBV infection was associated with IL-10-1082 AG (P = 0.001) and GG (P = 0.004) genotypes and G (P = 0.000) allele. IL-10-819 T/C and -592 A/C genotype and allele frequencies did not show any correlation with the risk of chronic hepatitis B infection. These results suggest that polymorphisms in interleukin-10 gene promoter influence clinical outcome of HBV infection and susceptibility to HBV infection.
Elgroud, Rachid; Granier, Sophie A.; Marault, Muriel; Kerouanton, Annaëlle; Lezzar, Abdesslem; Bouzitouna-Bentchouala, Chafia; Brisabois, Anne; Millemann, Yves
2015-01-01
An epidemiological investigation was carried out on one hundred Salmonella isolates from broiler farms, slaughterhouses, and human patients in the Constantine region of Algeria, in order to explore the contribution of avian strains to human salmonellosis cases in this region over the same period of time. The isolates were characterized by phenotypic as well as genotypic methods. A large variety of antimicrobial resistance profiles was found among human isolates, while only seven profiles were found among avian isolates. Enterobacterial Repetitive Intergenic Consensus-PCR (ERIC-PCR), Insertion Sequence 200-PCR (IS200-PCR), and Pulsed Field Gel Electrophoresis (PFGE) resulted in the allocation of the isolates to 16, 20, and 34 different profiles, respectively. The 3 genotyping methods led to complementary results by underlining the clonality of some serovars with the diffusion and persistence of a single clone in the Constantine area as well as stressing the polymorphism present in isolates belonging to other serovars, indicating the diversity of potential reservoirs of nontyphoidal Salmonella. Altogether, our results seem to indicate that nontyphoidal avian Salmonella may play an important role in human salmonellosis in the Constantine region. PMID:26543858
Regulation of emotional response in juvenile monkeys treated with fluoxetine: MAOA interactions
Golub, M. S.; Phi, C. E.; Bulleri, A. M.
2016-01-01
Juvenile male rhesus macaques received therapeutic doses of fluoxetine daily from one to three years of age and were compared to vehicle-treated controls (N=16/group). Genotyping for monoamine oxidase A (MAOA) polymorphisms was used to form subgroups (N=8) with high and low expression of the gene. Behavioral responses were scored during 30-second exposures to pictures differing in affective content. As expected from its therapeutic effect, fluoxetine decreased the behavioral response to emotionally evocative pictures. A 44% reduction in number of expressive behaviors was seen, but only in subjects with low expression MAOA polymorphisms. In general, this effect occurred for pictures of varying affective content and was not due to altered occurrence of one specific behavior or type of behavior. The drug*genotype interaction was seen after one and two years of treatment and did not reverse one year after discontinuation of dosing. Two potential translational implications are suggested: (1) MAOA genetic polymorphisms may be the source of some of the variability in response to fluoxetine treatment in children; (2) extended fluoxetine treatment during juvenile brain development may result in persistent effects on emotional regulation. PMID:27852517
Evolution of Functional Diversification within Quasispecies
Colizzi, Enrico Sandro; Hogeweg, Paulien
2014-01-01
According to quasispecies theory, high mutation rates limit the amount of information genomes can store (Eigen’s Paradox), whereas genomes with higher degrees of neutrality may be selected even at the expenses of higher replication rates (the “survival of the flattest” effect). Introducing a complex genotype to phenotype map, such as RNA folding, epitomizes such effect because of the existence of neutral networks and their exploitation by evolution, affecting both population structure and genome composition. We reexamine these classical results in the light of an RNA-based system that can evolve its own ecology. Contrary to expectations, we find that quasispecies evolving at high mutation rates are steep and characterized by one master sequence. Importantly, the analysis of the system and the characterization of the evolved quasispecies reveal the emergence of functionalities as phenotypes of nonreplicating genotypes, whose presence is crucial for the overall viability and stability of the system. In other words, the master sequence codes for the information of the entire ecosystem, whereas the decoding happens, stochastically, through mutations. We show that this solution quickly outcompetes strategies based on genomes with a high degree of neutrality. In conclusion, individually coded but ecosystem-based diversity evolves and persists indefinitely close to the Information Threshold. PMID:25056399
Regulation of emotional response in juvenile monkeys treated with fluoxetine: MAOA interactions.
Golub, M S; Hogrefe, C E; Bulleri, A M
2016-12-01
Juvenile male rhesus macaques received therapeutic doses of fluoxetine daily from one to three years of age and were compared to vehicle-treated controls (N=16/group). Genotyping for monoamine oxidase A (MAOA) polymorphisms was used to form subgroups (N=8) with high and low expression of the gene. Behavioral responses were scored during 30-second exposures to pictures differing in affective content. As expected from its therapeutic effect, fluoxetine decreased the behavioral response to emotionally evocative pictures. A 44% reduction in number of expressive behaviors was seen, but only in subjects with low expression MAOA polymorphisms. In general, this effect occurred for pictures of varying affective content and was not due to altered occurrence of one specific behavior or type of behavior. The drug*genotype interaction was seen after one and two years of treatment and did not reverse one year after discontinuation of dosing. Two potential translational implications are suggested: (1) MAOA genetic polymorphisms may be the source of some of the variability in response to fluoxetine treatment in children; (2) extended fluoxetine treatment during juvenile brain development may result in persistent effects on emotional regulation. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.
Social environment influences the relationship between genotype and gene expression in wild baboons
Runcie, Daniel E.; Wiedmann, Ralph T.; Archie, Elizabeth A.; Altmann, Jeanne; Wray, Gregory A.; Alberts, Susan C.; Tung, Jenny
2013-01-01
Variation in the social environment can have profound effects on survival and reproduction in wild social mammals. However, we know little about the degree to which these effects are influenced by genetic differences among individuals, and conversely, the degree to which social environmental variation mediates genetic reaction norms. To better understand these relationships, we investigated the potential for dominance rank, social connectedness and group size to modify the effects of genetic variation on gene expression in the wild baboons of the Amboseli basin. We found evidence for a number of gene–environment interactions (GEIs) associated with variation in the social environment, encompassing social environments experienced in adulthood as well as persistent effects of early life social environment. Social connectedness, maternal dominance rank and group size all interacted with genotype to influence gene expression in at least one sex, and either in early life or in adulthood. These results suggest that social and behavioural variation, akin to other factors such as age and sex, can impact the genotype–phenotype relationship. We conclude that GEIs mediated by the social environment are important in the evolution and maintenance of individual differences in wild social mammals, including individual differences in responses to social stressors. PMID:23569293
Santos, Kemper Nunes dos; Almeida, Marcella Kelly Costa de; Fecury, Amanda Alves; Costa, Carlos Araújo da; Martins, Luísa Caricio
2015-01-01
The hepatitis C virus has been recognized as the leading cause of chronic liver disease in the world. Host genetic factors have been implicated in the persistence of hepatitis C virus infection. Single nucleotide polymorphisms at positions -607 C/A (rs1946518) and -137 G/C (rs187238) in the IL-18 gene promoter have been suggested to be associated with delayed hepatitis C virus clearance and persistence of the disease. Identify these polymorphisms in a population infected with hepatitis C virus from the Brazilian Amazon region. In a cross-sectional analytical study conducted in Belém, Pará, Brazil, 304 patients infected with hepatitis C virus were divided into two groups: group A, patients with persistent infection; group B, patients with spontaneous clearance. The control group consisted of 376 volunteers not infected with hepatitis C virus. Samples were analyzed by RT-PCR for the detection of viral RNA and by RFLP-PCR to evaluate the presence of the -137 G/C and -607 C/A IL-18 gene promoter polymorphisms. Comparison of polymorphism allele frequencies between the patient and control groups showed a higher frequency of allele C at position -607 among patients (P=0.02). When the association between the polymorphisms and viral infection was analyzed, patients carrying genotype C/A at position -607 were found to be at higher risk of persistent hepatitis C virus infection (P=0.03). The present results suggest a possible role of the -607 IL-18 gene promoter polymorphism in the pathogenesis of hepatitis C virus infection.
2010-01-01
Background HPV burden is a predictor for high-grade cervical intraepithelial neoplasia and cancer. The natural history of HPV load in young women being recently exposed to HPV is described in this paper. Methods A total of 636 female university students were followed for 2 years. Cervical specimens with HPV-16, -18, -31, or -45 DNA by consensus PCR were further evaluated with type-specific and β-globin real-time PCR assays. Proportional hazards regression was used to estimate hazard ratios (HR) of infection clearance. Generalized estimating equations assessed whether HPV loads was predictive of HPV infection at the subsequent visit. Results HPV loads were consistently higher among women <25 years old, and those who had multiple sex partners, multiple HPV type infections and smokers. HPV-16 integration was encountered only in one sample. Infection clearance was faster among women at lower tertiles of HPV-16 (HR = 2.8, 95%CI: 1.0-8.1), HPV-18 (HR = 3.5, 95%CI: 1.1-11.2) or combined (HR = 2.4, 95%CI: 1.8-6.2) DNA loads. The relationship between HPV-16 and HPV-18 DNA loads and infection clearance followed a clear dose-response pattern, after adjusting for age and number of sexual partners. GEE Odds Ratios for HPV persistence of the middle and upper tertiles relative to the lower tertile were 2.7 and 3.0 for HPV-16 and 3.8 and 39.1 for HPV-18, respectively. There was no association between HPV-31 or -45 DNA loads and persistence. Conclusions The association between HPV load and persistence is not uniform across high-risk genital genotypes. HPV-16 integration was only rarely demonstrated in young women. PMID:21070660
Stewart, Garrick C.; Lopez-Molina, Javier; Gottumukkala, Raju V.; Rosner, Gregg F.; Anello, Mary S.; Hecht, Jonathan L.; Winters, Gayle L.; Padera, Robert F.; Baughman, Kenneth L.; Lipes, Myra A.
2011-01-01
Background Multiple viruses have been isolated from the heart, but their significance remains controversial. We sought to determine the prevalence of cardiotropic viruses in endomyocardial biopsy (EMB) samples from adult heart failure (HF) patients and to define the clinicopathologic profile of patients exhibiting viral positivity. Methods and Results EMB from 100 patients (median EF 30%, IQR 20–45%) presenting for cardiomyopathy evaluation (median symptom duration 5 months, IQR 1–13 months) were analyzed by polymerase chain reaction for adenovirus, cytomegalovirus, enteroviruses, Epstein-Barr virus, and parvovirus B19. Each isolate was sequenced and viral load was determined. Parvovirus B19 was the only virus detected in EMB samples (12% of subjects). No subject had anti-parvovirus IgM antibodies, but all had IgG antibodies, suggesting viral persistence. The clinical presentation of parvovirus-positive patients was markedly heterogeneous, with both acute and chronic HF, variable ventricular function, and ischemic cardiomyopathy. No subject met Dallas histopathological criteria for active or borderline myocarditis. Two patients with a positive cardiac MRI and presumed “parvomyocarditis” had similar viral loads as autopsy controls without heart disease. The oldest parvovirus-positive subjects were positive for genotype 2, suggesting lifelong persistence in heart tissue. Conclusions Parvovirus B19 was the only virus isolated from EMB samples in this series of adult HF patients from the United States. Positivity was associated with a wide array of clinical presentations and heart failure phenotypes. Our studies do not support a causative role for parvovirus B19 persistence in HF and therefore advocate against the use of antiviral therapy for these patients. PMID:21097605
Clinical features of celiac disease: a prospective birth cohort.
Agardh, Daniel; Lee, Hye-Seung; Kurppa, Kalle; Simell, Ville; Aronsson, Carin Andrén; Jörneus, Ola; Hummel, Michael; Liu, Edwin; Koletzko, Sibylle
2015-04-01
To investigate clinical features of celiac disease (CD) and their association with risk factors for CD in a genetic risk birth cohort. Children from 6 clinical centers in 4 countries positive for HLA-DR3-DQ2 or DR4-DQ8 were annually screened for tissue transglutaminase antibodies (tTGA) and assessed for symptoms by questionnaires. Associations of symptoms with anthropometrics, known risk factors for CD, tTGA levels, and mucosal lesions in those biopsied were examined. Of 6706 screened children, 914 developed persistent positive tTGA, 406 underwent biopsies, and 340 had CD. Compared with age-matched tTGA-negative children, those with persistent tTGA were more likely to have symptoms at 2 (34% vs 19%, P < .001) and 3 years of age (28% vs 19%, P = .009) but not at 4 years (27% vs 21%, NS). Z-scores for height, weight, and BMI did not differ between groups. In children with persistent tTGA, having ≥ 1 symptom was associated with family history of CD (odds ratio = 2.59, 95% confidence interval, 1.21-5.57) but not with age, gender, or HLA-DR3-DQ2 homozygosity. At seroconversion, tTGA levels were higher in symptomatic than asymptomatic children (P < .001), in those from CD families (P < .001), and in US participants (P < .001) but not associated with age, gender, or HLA genotype. tTGA levels correlated with severity of mucosal lesions both in symptomatic (r = 0.53, P < .001) and asymptomatic children (r = 0.22, P = .01). A majority of children detected with persistent tTGA in screenings are asymptomatic and have normal growth by age 4 years. tTGA levels correlate more strongly with severity of mucosal lesions in symptomatic as compared with asymptomatic children. Copyright © 2015 by the American Academy of Pediatrics.
Xiao, Song S; Fan, Jie L; He, Si L; Li, Yue R; Wang, Lu Y; Yu, Ke N; Deng, Xin L; Xue, Min
2016-10-01
This study aimed to investigate the relationship between persistent human papillomavirus (HPV) infection and cervical lesion. Clinical data of 16,320 patients who visited our clinic between January 2009 and December 2013 were collected. Retrospective analysis was performed to analyze the overall HPV infection and compare the infection rates of different subtypes among different age groups, to reveal the relationship between persistent HPV infection and cervical cytology. The overall prevalence of HPV was 26.54%. The most common genotypes were HPV 52, HPV 16, HPV 58, CP8304, and HPV 53. The highest overall high-risk HPV prevalence was found in women older than 60 years, and the lowest prevalence was found in women between the ages of 30 and 39 years. There was no significant difference in low-risk HPV prevalence among different age groups (p = .693). The HPV clearance rate after 1 year among those with initial positive test was 87.65%. The constituent ratios of high- or low-risk HPV subtypes were not significantly different (p = .545) between nonpersistent-positive and persistent-positive (PP) groups. Conversely, the constituent ratios of singe- or multi-type HPV infection were significantly different (p < .05) between these 2 groups. The most common subtypes in PP group were HPV 16, 52, 58, CP8304, and 33. The occurrence rates of atypical squamous cells of undetermined significance, high-grade squamous intraepithelial lesion, and squamous cell carcinoma in the PP group significantly increased (p < .05). Persistent HPV infections are mainly caused by multiple types of HPV and high-risk HPV. Our region should particularly pay attention to the prevention and treatment of HPV 16, 52, and 58.
Sebastian, Nadia T; Zaikos, Thomas D; Terry, Valeri; Taschuk, Frances; McNamara, Lucy A; Onafuwa-Nuga, Adewunmi; Yucha, Ryan; Signer, Robert A J; Riddell, James; Bixby, Dale; Markowitz, Norman; Morrison, Sean J; Collins, Kathleen L
2017-07-01
Latent HIV infection of long-lived cells is a barrier to viral clearance. Hematopoietic stem and progenitor cells are a heterogeneous population of cells, some of which are long-lived. CXCR4-tropic HIVs infect a broad range of HSPC subtypes, including hematopoietic stem cells, which are multi-potent and long-lived. However, CCR5-tropic HIV infection is limited to more differentiated progenitor cells with life spans that are less well understood. Consistent with emerging data that restricted progenitor cells can be long-lived, we detected persistent HIV in restricted HSPC populations from optimally treated people. Further, genotypic and phenotypic analysis of amplified env alleles from donor samples indicated that both CXCR4- and CCR5-tropic viruses persisted in HSPCs. RNA profiling confirmed expression of HIV receptor RNA in a pattern that was consistent with in vitro and in vivo results. In addition, we characterized a CD4high HSPC sub-population that was preferentially targeted by a variety of CXCR4- and CCR5-tropic HIVs in vitro. Finally, we present strong evidence that HIV proviral genomes of both tropisms can be transmitted to CD4-negative daughter cells of multiple lineages in vivo. In some cases, the transmitted proviral genomes contained signature deletions that inactivated the virus, eliminating the possibility that coincidental infection explains the results. These data support a model in which both stem and non-stem cell progenitors serve as persistent reservoirs for CXCR4- and CCR5-tropic HIV proviral genomes that can be passed to daughter cells.
2.1 Natural History of Highly Pathogenic Avian Influenza H5N1
Sonnberg, Stephanie; Webby, Richard J.; Webster, Robert G.
2013-01-01
The ecology of highly pathogenic avian influenza (HPAI) H5N1 has significantly changed from sporadic outbreaks in terrestrial poultry to persistent circulation in terrestrial and aquatic poultry and potentially in wild waterfowl. A novel genotype of HPAI H5N1 arose in 1996 in southern China and through ongoing mutation, reassortment, and natural selection, has diverged into distinct lineages and expanded into multiple reservoir hosts. The evolution of Goose/Guangdong-lineage highly pathogenic H5N1 viruses is ongoing: while stable interactions exist with some reservoir hosts, these viruses are continuing to evolve and adapt to others, and pose an un-calculable risk to sporadic hosts, including humans. PMID:23735535
Souraud, J B; Faivre, A; Waku-Kouomou, D; Gaillard, T; Aouad, N; Meaudre, E; Wild, F T; Fouet, B; Soulard, R
2009-01-01
Subacute sclerosing panencephalitis is an uncommon progressive neurological disorder caused by a persistent defective measles virus, typically affecting children. We describe a case of fulminant subacute sclerosing panencephalitis in a 25-year-old male. Brain tissue biopsy showed histologic evidence of encephalitis with eosinophilic intranuclear inclusion bodies (Cowdry Type A and B), intracytoplasmic inclusion bodies, perivascular lymphoplasmacytic infiltration and gliosis. Immunohistochemical studies were positive using an anti-measles antibody. Reverse transcriptase-PCR detected measles virus RNA and phylogenetic analysis indicated a C2 genotype. The rare adult-onset form is often atypical and difficult to diagnose and should be included in the differential diagnosis of subacute "unexplained" neurological diseases and uncommon infectious disorders.
Milk consumption and lactose intolerance in adults.
Qiao, Rong; Huang, ChengYu; Du, HuiZhang; Zeng, Guo; Li, Ling; Ye, Sheng
2011-10-01
To investigate relations between milk consumption and lactose intolerance (LI) in adults and to explore the effect of milk consumption on lactase activity. Total of 182 subjects aged 20-70 years were recruited and interviewed by questionnaires, and their accumulative cow's milk intake (AMI) was calculated. LI was evaluated by hydrogen breath test (HBT). A negative correlation was found between AMI and severity of observed LI symptom (r=-0.2884; P<0.05). Binary logistic regression analysis showed a negative correlation between LI and duration and frequency of milk consumption (OR, 0.317 and 0.465, respectively; both P<0.05) and a positive correlation between LI and amount of milk consumed per sitting (OR, 6.337; P<0.05). LI is related to various milk consumption behaviors. Most Chinese adults with LI may tolerate moderate milk consumption <160 mL. Copyright © 2011 The Editorial Board of Biomedical and Environmental Sciences. Published by Elsevier B.V. All rights reserved.
Lactose intolerance and other disaccharidase deficiency.
Tomar, Balvir S
2014-09-01
Intolerance to foods which contain lactose can cause a range of intestinal and systemic symptoms. These symptoms are caused by Lactase deficiency which is encoded by a single gene (LCT) of ≈ 50 kb located on chromosome 2q21. In some food items, lactose has been missed because of "hidden" lactose due to inadequately labeled, confusing diagnosis of lactose intolerance based on dietary restriction of dairy foods. Two polymorphisms, C/T13910 and G/A22018, linked to hypolactasia, correlate with breath hydrogen and symptoms after lactose. The key in the management of lactose intolerance is the dietary removal of lactose. Patients diagnosed as lactose intolerant must be advised of "risk" foods, inadequately labeled, including processed meats, bread, cake mixes, soft drinks, and lagers. This review highlights the types, symptoms and management of lactose intolerance and also highlights differences from milk allergy which closely mimics the symptoms of lactose intolerance.
Soy infant formula: is it that bad?
Vandenplas, Yvan; De Greef, Elisabeth; Devreker, Thierry; Hauser, Bruno
2011-02-01
The objective of this study is to review the indications of soy infant formula (SIF). Structured review of publications is made available through standard search engines (Pubmed,…). The medical indications for SIF are limited to galactosaemia and hereditary lactase deficiency. In the treatment of cow's milk allergy, SIF is used for economic reasons, as extensive hydrolysates are expensive. SIF is dissuaded mainly because of its phytooestrogen content. Isoflavone serum levels are much higher in SIF-fed infants than in breastfed or cow milk formula-fed infants. Administration of pure isoflavones to animals causes decreased fertility, but clinically relevant adverse effects of SIF in infants are not reported. Soy infant formula remains an option for feeding of term born infants if breastfeeding is not possible and if standard infant formula is not tolerated. © 2010 The Author(s)/Acta Paediatrica © 2010 Foundation Acta Paediatrica.