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1

Molecular characterization and phylogenetic analysis of porcine epidemic diarrhea virus (PEDV) field isolates in Korea.  

PubMed

Porcine epidemic diarrhea virus (PEDV) has caused enteric disease with devastating impact since the first identification of PEDV in 1992 in Korea. In this study, we investigated molecular epidemiology, showed genetic diversity, and analyzed phylogenetic relationships of Korean PEDV field isolates with other PEDV reference strains. Genetic analysis of the complete M and ORF3 genes showed that each PEDV group had several unique characteristics, and this indicated that specific groups of PEDVs may be differentiated from the other PEDVs by specific nucleotide differences. Especially, ORF3 gene analysis can be used for discrimination between vaccine and wild-type PEDVs. Sequence and phylogenetic analysis showed that recent, prevalent Korean PEDV field isolates have close relationships to Chinese field strains and differ genetically from European strains and vaccine strains used in Korea. These results raise questions as to whether a new type of PEDV vaccine may be necessary for preventing PEDV infection more effectively in Korea. PMID:21210162

Park, Seong-Jun; Kim, Hye-Kwon; Song, Dae-Sub; Moon, Hyoung-Joon; Park, Bong-Kyun

2011-04-01

2

Molecular characterization and phylogenetic analysis of porcine epidemic diarrhea virus (PEDV) field isolates in Korea  

Microsoft Academic Search

Porcine epidemic diarrhea virus (PEDV) has caused enteric disease with devastating impact since the first identification of\\u000a PEDV in 1992 in Korea. In this study, we investigated molecular epidemiology, showed genetic diversity, and analyzed phylogenetic\\u000a relationships of Korean PEDV field isolates with other PEDV reference strains. Genetic analysis of the complete M and ORF3\\u000a genes showed that each PEDV group

Seong-Jun Park; Hye-Kwon Kim; Dae-Sub Song; Hyoung-Joon Moon; Bong-Kyun Park

2011-01-01

3

Molecular epidemiology and phylogenetic analysis of porcine epidemic diarrhea virus (PEDV) field isolates in Korea.  

PubMed

Porcine epidemic diarrhea virus (PEDV) has caused devastating enteric disease in Korean pig farms since its first identification in 1992 in Korea. In the present study, the molecular epidemiology, genetic diversity, and phylogenetic relationship of Korean PEDV field isolates to other reference strains were analyzed using the complete E gene. Genetic analysis showed that each PEDV group had several unique characteristics, which indicated that a specific group PEDVs may be differentiated from another group PEDVs. Phylogenetic analysis showed that recent prevalent Korean PEDV field isolates are closely related to the Chinese field strains and differ genetically from the European strains and the vaccine strains used in Korea, which raises questions of whether a new-type PEDV vaccine may be necessary for preventing PEDV infection more effectively in Korea. Notably, a large deletion identified only in the attenuated DR13 can be utilized as a genetic marker, and the methods developed in this study will help to rapidly detect and differentiate PEDVs. PMID:23462888

Park, Seong-Jun; Song, Dae-Sub; Park, Bong-Kyun

2013-07-01

4

Phylogenetic analysis of porcine epidemic diarrhea virus (PEDV) field strains in central China based on the ORF3 gene and the main neutralization epitopes.  

PubMed

Since 2010, porcine epidemic diarrhea has re-emerged with devastating impact on the swine-raising industry in central China. To investigate the epidemic characteristics of PEDV, the complete ORF3 genes of 14 PEDV field strains from central China during 2012 to 2013 were cloned, sequenced and compared with reference strains. Phylogenetic analysis based on the complete ORF3 gene showed that the PEDVs in central China and the reference strains could be divided into three groups: G1, G2, and G3. The 14 PEDV isolates were classified as G1 and showed a close relationship to some Chinese strains isolated previously in central China and differed genetically from recent isolates from southern China, Korean strains (SM98 and DB1865, 2012), the Chinese LZC strain (2007), and the vaccine strain (CV777) being used in China. Our findings suggested that the PEDVs circulating between 2012 and 2013 in central China might have evolved from earlier strains in the local region. To determine the reason for recent vaccination failures, we also studied variations in antigenicity of field strains by analyzing the three neutralizing epitope regions in the S gene. The results showed that the neutralizing epitopes at aa 245-252 were highly conserved, but most of the amino acid changes occurred in the epitope regions aa 7-146 and 271-278. We speculate that the amino acid mutations in the neutralizing epitope regions may be associated with changes in the antigenicity of PEDV and consequently result in vaccination failure. Together, these findings may be useful for understanding the epidemiology of PEDV and may be relevant for designing of new and more efficacious vaccines. PMID:24292967

Li, Renfeng; Qiao, Songlin; Yang, Yanyan; Su, Yunfang; Zhao, Pu; Zhou, Enmin; Zhang, Gaiping

2014-05-01

5

Molecular characterization and phylogenetic analysis of porcine epidemic diarrhea virus (PEDV) field strains in south China.  

PubMed

A total of 127 porcine samples were collected from 48 farms in six provinces in south China. The positive rate of porcine epidemic diarrhea virus (PEDV) was 43.0 % (55/127), and the co-infection rate of PEDV and transmissible gastroenteritis virus (TGEV) was 12.0 % (15/127). The partial S gene and complete M gene were amplified from PEDV-positive strains by RT-PCR, cloned, sequenced and compared with each other, as well as with the reference strains in GenBank. Sequence homology results of the partial S gene and complete M gene showed that all south China field PEDV strains had nucleotide (deduced amino acid) sequence identities of 86.7-98.7 % (83.2-99.3 %) and 96.1-100 % (95.0-100%), respectively, with the foreign reference strains reported in GenBank. Phylogenetic analysis of the partial S gene showed that all the south China PEDV strains and two Thailand strains (08UB01 and 08RB07) belong to the same group and differ genetically from European strains and early domestic strains. Phylogenetic analysis of the complete M gene showed that all south China PEDV strains have a close relationship with most of the strains in Korea and Thailand, but differ genetically from the vaccine strain (CV777). PMID:22528639

Li, Zhi-Li; Zhu, Ling; Ma, Jing-Yun; Zhou, Qing-Feng; Song, Yan-Hua; Sun, Bao-Li; Chen, Rui-Ai; Xie, Qing-Mei; Bee, Ying-Zuo

2012-08-01

6

Derivation of attenuated porcine epidemic diarrhea virus (PEDV) as vaccine candidate  

Microsoft Academic Search

The field isolate of porcine epidemic diarrhea virus (PEDV) was serially passaged in Vero cells. The cell passaged PEDV, designated KPEDV-9, was tested for its pathogenicity in the neonatal pigs, immunogenicity and safety in the pregnant sows. The result indicated that KPEDV-9 at the 93rd passage revealed reduced pathogenicity in the neonatal pigs. Pregnant sows inoculated with the attenuated virus

Chang-Hee Kweon; Byung-Joon Kwon; Jae-Gil Lee; Geon-Oh Kwon; Yung-Bai Kang

1999-01-01

7

Molecular characterization and phylogenetic analysis of porcine epidemic diarrhea virus (PEDV) samples from field cases in Fujian, China.  

PubMed

The outbreak of porcine epidemic diarrhea virus (PEDV) has been a big problem of swine industry in China in recent years. In this study, we investigated molecular diversity, phylogenetic relationships, and protein characterization of Fujian field samples with other PEDV reference strains. Sequence analysis of the S1 and sM genes showed that each sample had unique characteristics, and the sample P55 may be differentiated from the others by the unique deletions and insertions of sM gene. Phylogenetic analysis based on S1 or sM gene, which have high levels of variations, indicated that each sample was related to the specific reference strain, and this finding was consistent with the protein characterization prediction analysis. The study is useful to better understand the prevalence of PEDV and its prevention and control in Fujian. PMID:22843324

Chen, Xi; Yang, Jinxian; Yu, Fusong; Ge, Junqing; Lin, Tianlong; Song, Tieying

2012-12-01

8

Derivation of attenuated porcine epidemic diarrhea virus (PEDV) as vaccine candidate.  

PubMed

The field isolate of porcine epidemic diarrhea virus (PEDV) was serially passaged in Vero cells. The cell passaged PEDV, designated KPEDV-9, was tested for its pathogenicity in the neonatal pigs, immunogenicity and safety in the pregnant sows. The result indicated that KPEDV-9 at the 93rd passage revealed reduced pathogenicity in the neonatal pigs. Pregnant sows inoculated with the attenuated virus showed increased immune responses by ELISA. In addition, delivered piglets were protected from challenge of wild type PEDV. The safety test in pregnant sows indicated that all inoculated animals farrowed the average numbers of litters of piglets. The results of this study supported that the attenuated virus derived from serial passage could be applied as vaccine for protecting suckling piglets against PEDV infection. PMID:10418901

Kweon, C H; Kwon, B J; Lee, J G; Kwon, G O; Kang, Y B

1999-06-01

9

Whole-genome analysis of porcine epidemic diarrhea virus (PEDV) from eastern China.  

PubMed

The complete genome sequence of a porcine epidemic diarrhea virus variant, strain SHQP/YM/2013, from China was determined and compared with those of other porcine epidemic diarrhea viruses. The full-length genome was 28,038 nucleotides (nt) in length without the poly (A) tail, and it was similar to that of other reported PEDV strains, with the characteristic gene order 5'-replicase (1a/1b) -S-ORF3-E-M-N-3'. Nucleotide sequence analysis based on individual virus genes indicated a close relationship between the S gene of SHQP/YM/2013 and those of the four Korean field strains from 2008-2009. Its ORF3 gene, however, fell into three groups. Recent prevalent Chinese PEDV field isolates were divided between group 1 and group 3, which suggests that the recent prevalent Chinese PEDV field isolates represent a new genotype that differs from the genotype that includes the vaccine strains. Based on phylogenetic analysis of the M gene, ORF3 gene and S gene, our study demonstrated that prevalent PEDV isolates in China may have originated from Korean strains. This report describes the complete genome sequence of SHQP/YM/2013, and the data will promote a better understanding of the molecular epidemiology and genetic diversity of PEDV field isolates in eastern China. PMID:24818713

Yang, De-Quan; Ge, Fei-Fei; Ju, Hou-Bin; Wang, Jian; Liu, Jian; Ning, Kun; Liu, Pei-Hong; Zhou, Jin-Ping; Sun, Quan-Yun

2014-10-01

10

Genetic differentiation of the nucleocapsid protein of Korean isolates of porcine epidemic diarrhoea virus by RT-PCR based restriction fragment length polymorphism analysis  

Microsoft Academic Search

A reverse transcriptase polymerase chain reaction (RT-PCR) based restriction fragment length polymorphism (RFLP) analysis based on the nucleocapsid (N) gene was developed to differentiate between field isolates of porcine epidemic diarrhoea virus (PEDV) and a vaccine strain, J-vac. Thirteen field isolates of PEDV from Korea were distinguishable from the vaccine strain and the prototype PEDV strain CV777 by RFLP using

Changhee Lee; Choi-Kyu Park; Young S. Lyoo; Du Sik Lee

2008-01-01

11

Isotype-specific antibody-secreting cells in systemic and mucosal associated lymphoid tissues and antibody responses in serum of conventional pigs inoculated with PEDV.  

PubMed

An enzyme-linked immunospot (ELISPOT) has been developed to detect porcine epidemic diarrhea virus (PEDV)-specific antibody secreting cells (ASC) in gut associated lymphoid tissues (duodenum and ileum lamina propria and mesenteric lymph nodes) and systemic locations (spleen and blood) of conventional pigs so as to characterise the mucosal and systemic antibody response generated by the infection with PEDV. A total number of 28 eleven-day-old conventional pigs were orally inoculated with the field isolate of the PEDV strain CV-777. Diarrhea was observed in 32% of the pigs and virus shedding was demonstrated in 100% between postinoculation day (PID) 1 and 8. Serum IgG and IgA antibodies to PEDV were detected by isotype ELISA from PID 12 and 15, respectively, reaching maximum values at PID 32 (IgG) and 21 (IgA). PEDV specific IgM ASC occurred in all the tissues between PID 4 and 7, with the strongest response in the intestinal lamina propria. IgA and IgG ASC responses were evident in the intestinal lymphoid tissues from PID 21, the highest number of specific ASC corresponded to the duodenum lamina propria. In the systemic lymphoid tissues the number of IgG and IgA ASC detected were lower than in the mucosal tissues, however, in the blood, presence of IgA ASC was constantly detected from PID 14 until the end of the experiment. Memory antibody response to the PEDV was also studied by secondary in vitro stimulation of the mononuclear cells (MNC) isolated from mesenteric lymph nodes, spleen and blood. The memory B cell response was prominent at PID 21 and 25 and consisted in IgG and IgA ASC. To our knowledge, this is the first report to research into the presence and distribution of specific ASC in different locations of the systemic and the gut associated lymphoid tissues after a PEDV infection as well as the presence of memory B cells. PMID:11825594

de Arriba, M L; Carvajal, A; Pozo, J; Rubio, P

2002-01-01

12

Oleanane Triterpenes from the Flowers of Camellia japonica Inhibit Porcine Epidemic Diarrhea Virus (PEDV) Replication.  

PubMed

Porcine epidemic diarrhea virus (PEDV) infections have resulted in a severe economic loss in the swine industry in many countries due to no effective treatment approach. Fifteen oleanane triterpenes (1-15), including nine new ones (1-4 and 10-14), were isolated from the flowers of Camellia japonica, and their molecular structures were determined by extensive spectroscopic methods. These compounds were evaluated for their antiviral activity against PEDV replication, and the structure-activity relationships (SARs) were discussed. Compounds 6, 9, 11, and 13 showed most potent inhibitory effects on PEDV replication. They were found to inhibit PEDV genes encoding GP6 nucleocapsid, GP2 spike, and GP5 membrane protein synthesis based on RT-PCR data. Western blot analysis also demonstrated their inhibitory effects on PEDV GP6 nucleocapsid and GP2 spike protein synthesis during viral replication. The present study suggested the potential of compounds 6, 9, 11, and 13 as promising scaffolds for treating PEDV infection via inhibiting viral replication. PMID:25568928

Yang, Jun-Li; Ha, Thi-Kim-Quy; Dhodary, Basanta; Pyo, Euisun; Nguyen, Ngoc Hieu; Cho, Hyomoon; Kim, Eunhee; Oh, Won Keun

2015-02-12

13

Complete Genome Sequence of a Vero Cell-Adapted Isolate of Porcine Epidemic Diarrhea Virus in Eastern China  

PubMed Central

In early 2012, a widespread porcine epidemic diarrhea virus (PEDV) occurred in eastern China. A cell-adapted isolate, SD-M, was at the four-passage level of virulent field strain SD, which was isolated from a 2-day-old dead suckling piglet that had suffered from severe diarrhea in Shandong Province, China. We report here the complete genome sequence of SD-M. This sequence will promote a better understanding of the molecular pathogenesis of PEDV. PMID:23166259

Zhao, Mengjiao; Sun, Zhen; Zhang, Yue; Wang, Guisheng; Wang, Hui; Yang, Fangfang

2012-01-01

14

Development of a Hybridoma Cell Line Secreting Monoclonal Antibody Against S Protein of a Chinese Variant of PEDV.  

PubMed

Gene encoding 22-380 aa of spike protein of porcine epidemic diarrhea virus (PEDV) isolate in China was cloned and expressed as a recombinant protein in Escherichia coli BL21(DE3). Female BALB/c mice were immunized with the purified recombinant S protein, and a monoclonal antibody (MAb) designated as 2D1 against S protein was achieved by hybridoma technique. MAb 2D1 reacted with S protein of PEDV specifically. The monoclonal antibody 2D1 may provide a useful tool as a specific diagnostic reagent for detecting S protein of the Chinese variant of PEDV and for further investigation into the virus' pathogenic mechanism. PMID:25723278

Lei, Ximei; Zhao, Jun; Wang, Xiaomeng; Zhao, Yongxiang; Wang, Chuanqing

2015-02-01

15

Immunoprophylactic effect of chicken egg yolk immunoglobulin (Ig Y) against porcine epidemic diarrhea virus (PEDV) in piglets.  

PubMed

Porcine epidemic diarrhea virus (PEDV) is the causative agent of neonatal diarrhea in piglets, which causes high mortality rates. In this study, the immunoprophylactic effects of chicken egg yolk immunoglobulin (Ig Y) against PEDV were investigated in neonatal pigs. Ig Y was found to reduce the mortality in piglets after challenge exposures. The field application of Ig Y also revealed significant differences in survival rates of piglets given Ig Y, as compared with placebo or control. The results in this study indicated that Ig Y against PEDV could be an alternative way of supplementing prophylactic measures like colostral antibodies from sows. PMID:11039591

Kweon, C H; Kwon, B J; Woo, S R; Kim, J M; Woo, G H; Son, D H; Hur, W; Lee, Y S

2000-09-01

16

Isolation and characterization of a variant porcine epidemic diarrhea virus in China  

PubMed Central

An outbreak of diarrhea in pigs started in Guangdong, South China in January 2011. Cases were characterized by watery diarrhea, dehydration and vomiting, with 80–100% morbidity and 50–90% mortality in suckling piglets. The causative agent of the diarrhea was ultimately identified as porcine epidemic diarrhea virus (PEDV). In this study, we isolated a PEDV strain designated CHGD-01 from piglet intestines using Vero cell cultures, and its specific cytopathic effects were confirmed in susceptible cells by direct immunofluorescence testing and electron microscopy. The complete genome of CHGD-01 was shown to be 28,035 nucleotides in length, with a similar structure to that of PEDV reference strains. Phylogenetic analyses based on the whole genome revealed that CHGD-01 shared nucleotide sequence identities of 98.2–98.4% with two other Chinese isolates reported in the same year, thus constituting a new cluster. Amino acid sequence analysis based on individual virus genes indicated a close relationship between the spike protein gene of CHGD-01 and the field strain KNU0802 in Korea. Its ORF3 and nucleoprotein genes, however, were divergent from all other sequenced PEDV isolate clusters and therefore formed a new group, suggesting a new variant PEDV isolate in China. Further studies will be required to determine the immunogenicity and pathogenicity of this new variant. PMID:22967434

2012-01-01

17

Immune responses induced by DNA vaccines bearing Spike gene of PEDV combined with porcine IL-18.  

PubMed

Porcine epidemic diarrhea virus (PEDV) is the causative agent of porcine epidemic diarrhea, a highly contagious enteric disease of swine. The Spike (S) protein is one of the main structural proteins of PEDV capable of inducing neutralizing antibodies in vivo. Herein, we generated three distinct DNA constructs in the eukaryotic expression plasmid pVAX1; one encoding the S protein [pVAX1-(PEDV-S)], the second encoding the N-terminal fragment (S1) [pVAX1-(PEDV-S1)] containing potent antigenic sites, and the third expressing the porcine interleukin-18 (pIL-18) [pVAX1-(IL-18)]. Immunofluorescence assays in BHK-21 cells demonstrated successful protein expression from all 3 constructs. Kunming mice were injected separately with each of these constructs or with a pVAX1-(PEDV-S1)/pVAX1-(IL-18) combination, an attenuated PEDV vaccine, or vector only control. Animals were examined for T lymphocyte proliferation, anti-PEDV antibodies, IFN-? and IL-4 protein levels, and cytotoxic T cell function in mouse peripheral blood and spleen. In all cases, results showed that pVAX1-(PEDV-S) and the combination of pVAX1-(PEDV-S1) with pVAX1-(IL-18) induced the strongest responses; however, pIL-18 had no adjuvant effects when given in combination with pVAX1-(PEDV-S1). PMID:22643071

Suo, Siqingaowa; Ren, Yudong; Li, Guangxing; Zarlenga, Dante; Bu, Ri-E; Su, Dingding; Li, Xunliang; Li, Pengchong; Meng, Fandan; Wang, Chao; Ren, Xiaofeng

2012-08-01

18

Molecular characterization and phylogenetic analysis of membrane protein genes of porcine epidemic diarrhea virus isolates in China  

Microsoft Academic Search

Six porcine epidemic diarrhea viruses (PEDVs) were isolated from the fecal samples of piglets infected with PEDV in 2006 in\\u000a China. The membrane (M) protein genes of six PEDV isolates were amplified by reverse transcriptase-polymerase chain reaction\\u000a (RT-PCR), then cloned, sequenced, and compared with each other as well as those ten PEDV reference strains. The M protein\\u000a genes of six

Jian-Fei Chen; Dong-Bo Sun; Cheng-Bao Wang; Hong-Yan Shi; Xiao-Chen Cui; Sheng-Wang Liu; Hua-Ji Qiu; Li Feng

2008-01-01

19

PORCINE EPIDEMIC DIARRHEA VIRUS (PEDV) TESTING SUMMARY REPORT This report summarizes NAHLN laboratory testing for porcine epidemic diarrhea virus (PEDV) and covers testing through  

E-print Network

PORCINE EPIDEMIC DIARRHEA VIRUS (PEDV) TESTING SUMMARY REPORT This report summarizes NAHLN laboratory testing for porcine epidemic diarrhea virus (PEDV) and covers testing through 2 in this report are provided at the end of this report. CRITICAL UPDATES Test Results This Week Cumulative PEDV

Blanchette, Robert A.

20

Isolation and characterization of porcine epidemic diarrhea viruses associated with the 2013 disease outbreak in US swine  

Technology Transfer Automated Retrieval System (TEKTRAN)

Porcine epidemic diarrhea virus (PEDV) was detected for the first time in US swine in April 2013 and has caused significant economic loss. Obtaining a US PEDV isolate that can grow efficiently in cell culture is critical for PEDV pathogenesis study, diagnostic assays and vaccine development. It was ...

21

Development and evaluation of enzyme-linked immunosorbent assay based on recombinant nucleocapsid protein for detection of porcine epidemic diarrhea (PEDV) antibodies.  

PubMed

An enzyme-linked immunosorbent assays (ELISA) based on recombinant nucleocapsid (N) protein generated in Escherichia coli was evaluated for its sensitivity and specificity for diagnosis of porcine epidemic diarrhea (PEDV) infection. The N gene encoding the N protein was cloned and expressed as a fusion protein with His tag protein in E. coli. The recombinant N protein was migrated at 48 kDa and reacted with six histidine tag specific monoclonal antibody by immunoblotting. Recombinant N protein ELISA (rnELISA) demonstrated 98.7% specificities among (80) PEDV-free individuals, and 98% sensitivity ranging among (103) clinical samples with PEDV. On testing 884 field samples, an overall agreement of 88.3% was generated between the SN and rnELISA. Taken together, these results indicated that nucleocapsid protein may be a useful antigen for the sera-diagnosis of PEDV and it was also suggested that the ELISA is a highly sensitive and specific test for detecting antibodies to PEDV. PMID:17368968

Hou, Xi-Lin; Yu, Li-Yun; Liu, Jianzhu

2007-07-20

22

Completion of the porcine epidemic diarrhoea coronavirus (PEDV) genome sequence.  

PubMed

The sequence of the replicase gene of porcine epidemic diarrhoea virus (PEDV) has been determined. This completes the sequence of the entire genome of strain CV777, which was found to be 28,033 nucleotides (nt) in length (excluding the poly A-tail). A cloning strategy, which involves primers based on conserved regions in the predicted ORF1 products from other coronaviruses whose genome sequence has been determined, was used to amplify the equivalent, but as yet unknown, sequence of PEDV. Primary sequences derived from these products were used to design additional primers resulting in the amplification and sequencing of the entire ORF1 of PEDV. Analysis of the nucleotide sequences revealed a small open reading frame (ORF) located near the 5' end (no 99-137), and two large, slightly overlapping ORFs, ORF1a (nt 297-12650) and ORF1b (nt 12605-20641). The ORF1a and ORF1b sequences overlapped at a potential ribosomal frame shift site. The amino acid sequence analysis suggested the presence of several functional motifs within the putative ORF1 protein. By analogy to other coronavirus replicase gene products, three protease and one growth factor-like motif were seen in ORF1a, and one polymerase domain, one metal ion-binding domain, and one helicase motif could be assigned within ORF1b. Comparative amino acid sequence alignments revealed that PEDV is most closely related to human coronavirus (HCoV)-229E and transmissible gastroenteritis virus (TGEV) and less related to murine hepatitis virus (MHV) and infectious bronchitis virus (IBV). These results thus confirm and extend the findings from sequence analysis of the structural genes of PEDV. PMID:11724265

Kocherhans, R; Bridgen, A; Ackermann, M; Tobler, K

2001-01-01

23

Transverse Magnetic Field Propellant Isolator  

NASA Technical Reports Server (NTRS)

An alternative high voltage isolator for electric propulsion and ground-based ion source applications has been designed and tested. This design employs a transverse magnetic field that increases the breakdown voltage. The design can greatly enhance the operating range of laboratory isolators used for high voltage applications.

Foster, John E.

2000-01-01

24

Completion of the Porcine Epidemic Diarrhoea Coronavirus (PEDV) Genome Sequence  

Microsoft Academic Search

The sequence of the replicase gene of porcine epidemic diarrhoea virus (PEDV) has been determined. This completes the sequence of the entire genome of strain CV777, which was found to be 28,033 nucleotides (nt) in length (excluding the poly A-tail). A cloning strategy, which involves primers based on conserved regions in the predicted ORF1 products from other coronaviruses whose genome

Rolf Kocherhans; Anne Bridgen; Mathias Ackermann; Kurt Tobler

2001-01-01

25

Porcine Epidemic Diarrhea Virus Testing of Feeds Porcine epidemic diarrhea virus (PEDV) is transmitted by ingestion of fecal  

E-print Network

Porcine Epidemic Diarrhea Virus Testing of Feeds Porcine epidemic diarrhea virus (PEDV inoculations; PEDV replication is restricted to the intestinal tract. Much of what we know about transmission and risk of infection derives from our knowledge of transmissible gastroenteritis virus (TGEV). PEDV

Blanchette, Robert A.

26

Immune responses induced by DNA vaccines bearing Spike gene of PEDV combined with porcine IL-18  

Technology Transfer Automated Retrieval System (TEKTRAN)

Porcine epidemic diarrhea virus (PEDV) is the causative agent of porcine epidemic diarrhea, a highly contagious enteric disease of swine. The Spike (S) protein is one of the main structural proteins of PEDV capable of inducing neutralizing antibodies in vivo. Herein, we generated three distinct DNA ...

27

Sequence analysis of the partial spike glycoprotein gene of porcine epidemic diarrhea viruses isolated in Korea  

Microsoft Academic Search

Porcine epidemic diarrhea virus (PEDV) causes a devastating enteric disease with acute diarrhea, dehydration and significant\\u000a mortality in swine, thereby incurring heavy economic losses in Korea. Spike (S) glycoprotein has been suggested as an important\\u000a determinant for PEDV biological properties. In this study, the nucleotide and deduced amino acid sequences of the partial\\u000a S glycoprotein genes of Korean PEDV isolates,

Seong-Jun Park; Hyoung-Joon Moon; Jeong-Sun Yang; Chul-Seung Lee; Dae-Sub Song; Bo-Kyu Kang; Bong-Kyun Park

2007-01-01

28

Heterogeneity in spike protein genes of porcine epidemic diarrhea viruses isolated in Korea  

Microsoft Academic Search

Porcine epidemic diarrhea virus (PEDV) has plagued the domestic swine industry in Korea causing significant economic impacts on pig production nationwide. In the present study, we determined the complete nucleotide sequences of the spike (S) glycoprotein genes of seven Korean PEDV isolates. The entire S genes of all isolates were found to be nine nucleotides longer in length than other

Dong-Kyu Lee; Choi-Kyu Park; Seong-Hee Kim; Changhee Lee

2010-01-01

29

[Porcine aminopeptidase N is a functional receptor for the PEDV coronavirus].  

PubMed

Porcine epidemic diarrhea virus (PEDV) causes lethal diarrhea in piglets that leads to great economic losses in East Asia. It was reported that aminopeptidase N (APN) was the receptor for Transmissible gastroenteritis virus (TGEV), Human coronavirus 229E (HCoV-229E) and Feline coronavirus (FeCoV) which all belonged to group I coronavirus including PEDV. It was also confirmed previously that porcine aminopeptidase N (pAPN) could bind to PEDV, and anti-pAPN antibodies could inhibit the combination. To investigate whether pAPN was a receptor for PEDV, we transfected MDCK cells with porcine aminopeptidase (pAPN) cDNA and this enabled non-susceptible cells to support PEDV replication and serial viral propagation. Moreover, the infection was blocked by antibodies against pAPN, implying the critical role of pAPN during virus entry. In addition, immunofluorescence assays for detection of pAPN and PEDV antigens, together with neutralization assays using antibodies against pAPN, further confirmed the correlation between pAPN expression and viral replication in pAPN-transfected MDCK cells. These results indicated that pAPN is a functional receptor for PEDV. PMID:19634766

Li, Bao-xian; Ma, Guang-peng; Ge, Jun-wei; Li, Yi-jing

2009-05-01

30

Porcine aminopeptidase N is a functional receptor for the PEDV coronavirus.  

PubMed

Porcine epidemic diarrhea virus (PEDV) causes lethal diarrhea in piglets that leads to great economic losses in East Asia. It was reported that aminopeptidase N (APN) is the receptor for transmissible gastroenteritis virus (TGEV), human coronavirus 229E (HCoV-229E) and feline coronavirus (FeCoV) which all belong to group I coronavirus including as well as PEDV. It was also confirmed previously that porcine aminopeptidase N (pAPN) can bind to PEDV, and anti-pAPN antibodies may inhibit the combination. To investigate whether pAPN is a receptor for PEDV, we transfected MDCK cells with porcine aminopeptidase (pAPN) cDNA and this enabled non-susceptible cells to support PEDV replication and serial viral propagation. Moreover, the infection was blocked by antibodies against pAPN, implies the critical role of pAPN during virus entry. In addition, immunofluorescence assays for detection of pAPN and PEDV antigens, together with neutralization assays using antibodies against pAPN, further confirmed the correlation between pAPN expression and viral replication in pAPN-transfected MDCK cells. These results indicate that pAPN is a functional receptor for PEDV. PMID:17467767

Li, B X; Ge, J W; Li, Y J

2007-08-15

31

Full-Length Genome Sequence of a Plaque-Cloned Virulent Porcine Epidemic Diarrhea Virus Isolate (USA/Iowa/18984/2013) from a Midwestern U.S. Swine Herd  

PubMed Central

Porcine epidemic diarrhea (PED) was recognized in U.S. swine for the first time in early 2013. A plaque-purified PED virus (PEDV) isolate (USA/Iowa/18984/2013) was obtained from a diarrheic piglet. The isolate is genetically close to other previously reported U.S. PEDVs and recent Chinese PEDVs and was virulent when inoculated into neonatal pigs. PMID:24356830

Hoang, Hai; Killian, Mary L.; Madson, Darin M.; Arruda, Paulo H. E.; Sun, Dong; Schwartz, Kent J.

2013-01-01

32

Sequence and phylogenetic analysis of nucleocapsid genes of porcine epidemic diarrhea virus (PEDV) strains in China.  

PubMed

Porcine epidemic diarrhea virus (PEDV) causes acute diarrhea and dehydration with high mortality rates in swine. It has become increasingly problematic in China. Since the nucleocapsid (N) protein is highly conserved, it is a candidate protein for early diagnosis and vaccine development. In this study, the N genes of 15 PEDV strains were amplified by RT-PCR and cloned into the pMT-19T vector, sequenced, and compared to each other as well as to PEDV reference strains. The nucleotide sequences of the N gene of the Chinese PEDV strains consist of 1326 nucleotides and encode a 441-aa-long peptide. The nucleotide sequences of the fifteen PEDV strains in our study were 96.1-100 % identical to each other, and the deduced amino acid sequences were 94.8-100 % identical. Sequence comparison with other PEDV strains selected from GenBank revealed that their nucleotide sequences were 94.2-99.7 % identical to those of the Chinese PEDV strains, and their deduced amino acid sequences were 94.1-99.5 % identical. In addition, the fifteen strains showed a high degree of nucleotide sequence identity to the early domestic strains (98.4-99.7 %) except the LZC strain, but less sequence identity to the vaccine strain (CV777) used in China (94.7-97.7 %). Phylogenetic analysis showed that the Chinese PEDV strains are composed of a separate cluster including three early domestic strains (JS-2004-02, LJB/03 and DX) but differ genetically from the vaccine strain (CV777) and the early Korean strains (Chinju99 and SM98). PMID:23389550

Li, Zhili; Chen, Feng; Yuan, Yao; Zeng, Xiduo; Wei, Zhongyan; Zhu, Ling; Sun, Baoli; Xie, Qingmei; Cao, Yongchang; Xue, Chunyi; Ma, Jingyun; Bee, Yingzuo

2013-06-01

33

Porcine aminopeptidase N is a functional receptor for the PEDV coronavirus  

Microsoft Academic Search

Porcine epidemic diarrhea virus (PEDV) causes lethal diarrhea in piglets that leads to great economic losses in East Asia. It was reported that aminopeptidase N (APN) is the receptor for transmissible gastroenteritis virus (TGEV), human coronavirus 229E (HCoV-229E) and feline coronavirus (FeCoV) which all belong to group I coronavirus including as well as PEDV. It was also confirmed previously that

B. X. Li; J. W. Ge; Y. J. Li

2007-01-01

34

Distinct Characteristics and Complex Evolution of PEDV Strains, North America, May 2013–February 2014  

PubMed Central

Porcine epidemic diarrhea virus (PEDV), which emerged in the United States in 2013, has spread throughout North America. Limited availability of PEDV complete genomes worldwide has impeded our understanding of PEDV introduction into the United States. To determine the relationship between the North American strains and global emerging and historic PEDV strains, we sequenced and analyzed complete genomes of 74 strains from North America; the strains clustered into 2 distinct clades. Compared with the initially reported virulent US PEDV strains, 7 (9.7%) strains from 4 states contained insertions and deletions in the spike gene (S INDELs). These S INDEL strains share 99.8%–100% nt identity with each other and 96.2%–96.7% nt identity with the initial US strains. Furthermore, the S INDEL strains form a distinct cluster within North American clade II, sharing 98.6%–100% nt identity overall. In the United States, the S INDEL and original PEDV strains are co-circulating and could have been introduced simultaneously. PMID:25279722

Vlasova, Anastasia N.; Wang, Qiuhong; Culhane, Marie R.; Rossow, Kurt D.; Rovira, Albert; Collins, James; Saif, Linda J.

2014-01-01

35

A phage-displayed peptide recognizing porcine aminopeptidase N is a potent small molecule inhibitor of PEDV entry.  

PubMed

Three phage-displayed peptides designated H, S and F that recognize porcine aminopeptidase N (pAPN), the cellular receptor of porcine transmissible gastroenteritis virus (TGEV) were able to inhibit cell infection by TGEV. These same peptides had no inhibitory effects on infection of Vero cells by porcine epidemic diarrhea virus (PEDV). However, when PEDV, TGEV and porcine pseudorabies virus were incubated with peptide H (HVTTTFAPPPPR), only infection of Vero cells by PEDV was inhibited. Immunofluoresence assays indicated that inhibition of PEDV infection by peptide H was independent of pAPN. Western blots demonstrated that peptide H interacted with PEDV spike protein and that pre-treatment of PEDV with peptide H led to a higher inhibition than synchronous incubation with cells. These results indicate direct interaction with the virus is necessary to inhibit infectivity. Temperature shift assays demonstrated that peptide H inhibited pre-attachment of the virus to the cells. PMID:24889221

Meng, Fandan; Suo, Siqingaowa; Zarlenga, Dante S; Cong, Yingying; Ma, Xiaowei; Zhao, Qiong; Ren, Xiaofeng

2014-05-01

36

Quantitation, biological and physicochemical properties of cell culture-adapted porcine epidemic diarrhea coronavirus (PEDV).  

PubMed

The porcine epidemic coronavirus (PEDV), tentatively classified as a coronavirus, was adapted to Vero cells and a plaque test developed for infectivity titration, allowing us to test the biological and biophysical properties of the virus. Growth kinetics showed peak titers of 10(5.5) plaque-forming units ml-1 15 h after infection. Filtration experiments and electron microscopy revealed a particle diameter between 100 and 200 nm. The buoyant density of the virus was 1.18. The particle lost its infectivity on treatment with lipid solvents. Virus replication could not be inhibited by 5-iodo-2'-deoxyuridine. PEDV was moderately stable at 50 degrees C, but heat sensitivity was not altered by divalent cations. At 4 degrees C, the virus was stable between pH 5.0 and 9.0, but at 37 degrees C stability was restricted to the pH range 6.5-7.5. Viral infectivity was not impaired by ultrasonication or by multiple freezing and thawing. PEDV was not neutralized by transmissible gastroenteritis virus antiserum. On the basis of the tests carried out, PEDV is a pleomorphic, enveloped RNA virus with a particle diameter of approximately 150 nm and a buoyant density of 1.18. Infectivity depends on the presence of trypsin, and infected cells show a tendency to fuse and to form syncytia. All of these properties, as well as its physicochemical characteristics, allow PEDV to be classified as a coronavirus. PMID:2549681

Hofmann, M; Wyler, R

1989-06-01

37

Phage-displayed peptides having antigenic similarities with porcine epidemic diarrhea virus (PEDV) neutralizing epitopes.  

PubMed

Seven-mer phage random peptide libraries were panned against 2C10, a monoclonal antibody that showed neutralizing activities against PEDV. Recombinant M13 phages displaying the peptides SHRLP(Y/Q)(P/V) or GPRPVTH on the g3p minor coat protein showed strong binding affinity with 2C10 (70% and 30% of recovered phages, respectively) after multiple panning. Sequence analysis suggested that these peptides are similar with (1368)GPRLQPY(1374) found at the carboxy-terminal of the S protein. In neutralization inhibition assays, the two peptide motifs and a 24-mer synthetic peptide corresponding to the C-terminal endodomain of PEDV S protein were observed to compete for the antigen binding site of 2C10, as demonstrated by the loss or reduction of neutralizing activity of the monoclonal antibody. This new finding suggests that the newly discovered peptide motifs mimic a neutralizing epitope PEDV. PMID:16950494

Cruz, Deu John M; Kim, Chul-Joong; Shin, Hyun-Jin

2006-10-10

38

PEDV ORF3 encodes an ion channel protein and regulates virus production.  

PubMed

Several studies suggest that the open reading frame 3 (ORF3) gene of porcine epidemic diarrhea virus (PEDV) is related to viral infectivity and pathogenicity, but its function remains unknown. Here, we propose a structure model of the ORF3 protein consisting of four TM domains and forming a tetrameric assembly. ORF3 protein can be detected in PEDV-infected cells and it functions as an ion channel in both Xenopus laevis oocytes and yeast. Mutation analysis showed that Tyr170 in TM4 is important for potassium channel activity. Furthermore, viral production is reduced in infected Vero cells when ORF3 gene is silenced by siRNA. Interestingly, the ORF3 gene from an attenuated PEDV encodes a truncated protein with 49 nucleotide deletions, which lacks the ion channel activity. PMID:22245155

Wang, Kai; Lu, Wei; Chen, Jianfei; Xie, Shiqi; Shi, Hongyan; Hsu, Haojen; Yu, Wenjing; Xu, Ke; Bian, Chao; Fischer, Wolfgang B; Schwarz, Wolfgang; Feng, Li; Sun, Bing

2012-02-17

39

Porcine epidemic diarrhea virus (PEDV) co-infection induced chlamydial persistence/stress does not require viral replication.  

PubMed

Chlamydiae may exist at the site of infection in an alternative replicative form, called the aberrant body (AB). ABs are produced during a viable but non-infectious developmental state termed "persistence" or "chlamydial stress." As persistent/stressed chlamydiae: (i) may contribute to chronic inflammation observed in diseases like trachoma; and (ii) are more resistant to current anti-chlamydial drugs of choice, it is critical to better understand this developmental stage. We previously demonstrated that porcine epidemic diarrhea virus (PEDV) co-infection induced Chlamydia pecorum persistence/stress in culture. One critical characteristic of persistence/stress is that the chlamydiae remain viable and can reenter the normal developmental cycle when the stressor is removed. Thus, we hypothesized that PEDV-induced persistence would be reversible if viral replication was inhibited. Therefore, we performed time course experiments in which Vero cells were C. pecorum/PEDV infected in the presence of cycloheximide (CHX), which inhibits viral but not chlamydial protein synthesis. CHX-exposure inhibited PEDV replication, but did not inhibit induction of C. pecorum persistence at 24 h post-PEDV infection, as indicated by AB formation and reduced production of infectious EBs. Interestingly, production of infectious EBs resumed when CHX-exposed, co-infected cells were incubated 48-72 h post-PEDV co-infection. These data demonstrate that PEDV co-infection-induced chlamydial persistence/stress is reversible and suggest that this induction (i) does not require viral replication in host cells; and (ii) does not require de novo host or viral protein synthesis. These data also suggest that viral binding and/or entry may be required for this effect. Because the PEDV host cell receptor (CD13 or aminopeptidase N) stimulates cellular signaling pathways in the absence of PEDV infection, we suspect that PEDV co-infection might alter CD13 function and induce the chlamydiae to enter the persistent state. PMID:24660163

Schoborg, Robert V; Borel, Nicole

2014-01-01

40

Porcine epidemic diarrhea virus (PEDV) co-infection induced chlamydial persistence/stress does not require viral replication  

PubMed Central

Chlamydiae may exist at the site of infection in an alternative replicative form, called the aberrant body (AB). ABs are produced during a viable but non-infectious developmental state termed “persistence” or “chlamydial stress.” As persistent/stressed chlamydiae: (i) may contribute to chronic inflammation observed in diseases like trachoma; and (ii) are more resistant to current anti-chlamydial drugs of choice, it is critical to better understand this developmental stage. We previously demonstrated that porcine epidemic diarrhea virus (PEDV) co-infection induced Chlamydia pecorum persistence/stress in culture. One critical characteristic of persistence/stress is that the chlamydiae remain viable and can reenter the normal developmental cycle when the stressor is removed. Thus, we hypothesized that PEDV-induced persistence would be reversible if viral replication was inhibited. Therefore, we performed time course experiments in which Vero cells were C. pecorum/PEDV infected in the presence of cycloheximide (CHX), which inhibits viral but not chlamydial protein synthesis. CHX-exposure inhibited PEDV replication, but did not inhibit induction of C. pecorum persistence at 24 h post-PEDV infection, as indicated by AB formation and reduced production of infectious EBs. Interestingly, production of infectious EBs resumed when CHX-exposed, co-infected cells were incubated 48–72 h post-PEDV co-infection. These data demonstrate that PEDV co-infection-induced chlamydial persistence/stress is reversible and suggest that this induction (i) does not require viral replication in host cells; and (ii) does not require de novo host or viral protein synthesis. These data also suggest that viral binding and/or entry may be required for this effect. Because the PEDV host cell receptor (CD13 or aminopeptidase N) stimulates cellular signaling pathways in the absence of PEDV infection, we suspect that PEDV co-infection might alter CD13 function and induce the chlamydiae to enter the persistent state. PMID:24660163

Schoborg, Robert V.; Borel, Nicole

2014-01-01

41

Surface-displayed porcine epidemic diarrhea viral (PEDV) antigens on lactic acid bacteria.  

PubMed

In this report, for surface display of viral antigen on lactobacilli, we have developed a surface antigen display system using the poly-gamma-glutamate synthetase A protein (pgsA) of Bacillus subtilis as an anchoring matrix. Recombinant fusion proteins comprised of pgsA and neucleocapsid protein of PEDV were stably expressed in Lactobacillus casei. Surface location of fusion protein was verified by ELISA, immunofluoresence microscopy. Oral and intranasal inoculations of recombinant L. casei into pregnant sow and mice resulted in high levels of serum immunoglobuline G (IgG) and mucosal IgA, as demonstrated by rnELISA(recombinant N protein ELISA) using recombinant N protein. Absorbance of IgG in pregnant sow sera highly increased duration of the experiment. More importantly, the level of IgA in colostrum were increased significantly higher than that of IgG. The IgG levels of the piglets were increased after suckling colostrum secreted from sows previously inoculated recombinant L. casei. These results indicate that mucosal immunization with recombinant L. casei expressing PEDV N protein (neucleoprotein of PEDV) on its surface elicited high levels of mucosal IgA and circulation IgG immune responses against the antigen N of PEDV. PMID:18054413

Hou, Xi-Lin; Yu, Li-Yun; Liu, Jianzhu; Wang, Gui-Hua

2007-12-21

42

Isolation and Characterization of Porcine Epidemic Diarrhea Viruses Associated with the 2013 Disease Outbreak among Swine in the United States  

PubMed Central

Porcine epidemic diarrhea virus (PEDV) was detected in May 2013 for the first time in U.S. swine and has since caused significant economic loss. Obtaining a U.S. PEDV isolate that can grow efficiently in cell culture is critical for investigating pathogenesis and developing diagnostic assays and for vaccine development. An additional objective was to determine which gene(s) of PEDV is most suitable for studying the genetic relatedness of the virus. Here we describe two PEDV isolates (ISU13-19338E and ISU13-22038) successfully obtained from the small intestines of piglets from sow farms in Indiana and Iowa, respectively. The two isolates have been serially propagated in cell culture for over 30 passages and were characterized for the first 10 passages. Virus production in cell culture was confirmed by PEDV-specific real-time reverse-transcription PCR (RT-PCR), immunofluorescence assays, and electron microscopy. The infectious titers of the viruses during the first 10 passages ranged from 6 × 102 to 2 × 105 50% tissue culture infective doses (TCID50)/ml. In addition, the full-length genome sequences of six viruses (ISU13-19338E homogenate, P3, and P9; ISU13-22038 homogenate, P3, and P9) were determined. Genetically, the two PEDV isolates were relatively stable during the first 10 passages in cell culture. Sequences were also compared to those of 4 additional U.S. PEDV strains and 23 non-U.S. strains. All U.S. PEDV strains were genetically closely related to each other (?99.7% nucleotide identity) and were most genetically similar to Chinese strains reported in 2011 to 2012. Phylogenetic analyses using different genes of PEDV suggested that the full-length spike gene or the S1 portion is appropriate for sequencing to study the genetic relatedness of these viruses. PMID:24197882

Chen, Qi; Li, Ganwu; Stasko, Judith; Thomas, Joseph T.; Stensland, Wendy R.; Pillatzki, Angela E.; Gauger, Phillip C.; Schwartz, Kent J.; Madson, Darin; Yoon, Kyoung-Jin; Stevenson, Gregory W.; Burrough, Eric R.; Harmon, Karen M.; Main, Rodger G.

2014-01-01

43

Gradient isolator for flow field of fuel cell assembly  

DOEpatents

Isolator(s) include isolating material and optionally gasketing material strategically positioned within a fuel cell assembly. The isolating material is disposed between a solid electrolyte and a metal flow field plate. Reactant fluid carried by flow field plate channel(s) forms a generally transverse electrochemical gradient. The isolator(s) serve to isolate electrochemically a portion of the flow field plate, for example, transversely outward from the channel(s), from the electrochemical gradient. Further, the isolator(s) serve to protect a portion of the solid electrolyte from metallic ions. 4 figs.

Ernst, W.D.

1999-06-15

44

Gradient isolator for flow field of fuel cell assembly  

DOEpatents

Isolator(s) include isolating material and optionally gasketing material strategically positioned within a fuel cell assembly. The isolating material is disposed between a solid electrolyte and a metal flow field plate. Reactant fluid carried by flow field plate channel(s) forms a generally transverse electrochemical gradient. The isolator(s) serve to isolate electrochemically a portion of the flow field plate, for example, transversely outward from the channel(s), from the electrochemical gradient. Further, the isolator(s) serve to protect a portion of the solid electrolyte from metallic ions.

Ernst, William D. (Troy, NY)

1999-01-01

45

Phage-displayed peptides having antigenic similarities with porcine epidemic diarrhea virus (PEDV) neutralizing epitopes  

Microsoft Academic Search

Seven-mer phage random peptide libraries were panned against 2C10, a monoclonal antibody that showed neutralizing activities against PEDV. Recombinant M13 phages displaying the peptides SHRLP(Y\\/Q)(P\\/V) or GPRPVTH on the g3p minor coat protein showed strong binding affinity with 2C10 (70% and 30% of recovered phages, respectively) after multiple panning. Sequence analysis suggested that these peptides are similar with 1368GPRLQPY1374 found

Deu John M. Cruz; Chul-Joong Kim; Hyun-Jin Shin

2006-01-01

46

Performance assessment of a real-time polymerase chain reaction assay for porcine epidemic diarrhea virus to assess PEDV transmission in growing pigs  

Technology Transfer Automated Retrieval System (TEKTRAN)

PEDV was first diagnosed in the U.S. in April 2013 as sporadic cases of diarrhea in young piglets with high mortality. Real-time RT-PCR is a high throughput test system that has potential to detect PEDV during the acute phase of the infection or pre-seroconversion. A study in nursery pigs was conduc...

47

Isotype-specific antibody-secreting cells in systemic and mucosal associated lymphoid tissues and antibody responses in serum of conventional pigs inoculated with PEDV  

Microsoft Academic Search

An enzyme-linked immunospot (ELISPOT) has been developed to detect porcine epidemic diarrhea virus (PEDV)-specific antibody secreting cells (ASC) in gut associated lymphoid tissues (duodenum and ileum lamina propria and mesenteric lymph nodes) and systemic locations (spleen and blood) of conventional pigs so as to characterise the mucosal and systemic antibody response generated by the infection with PEDV. A total number

M. L de Arriba; A Carvajal; J Pozo; P Rubio

2002-01-01

48

Analysis of protein expression changes of the Vero E6 cells infected with classic PEDV strain CV777 by using quantitative proteomic technique.  

PubMed

Recent outbreaks of porcine epidemic diarrhea virus (PEDV) have caused widespread concern. The identification of proteins associated with PEDV infection might provide insight into PEDV pathogenesis and facilitate the development of novel antiviral strategies. We analyzed the differential protein profile of PEDV-infected Vero E6 cells using mass spectrometry and an isobaric tag for relative and absolute quantification. A total of 126 proteins were identified that were differentially expressed between the PEDV-infected and mock-infected groups (P<0.05, quantitative ratio ?1.2), among which the expression of 58 proteins was up-regulated and that of 68 proteins was down-regulated in the PEDV-infected Vero E6 cells, involving in integrin ?2/?3, cystatin-C. The Gene Ontology analysis indicated that the molecular function of the differentially expressed proteins (DEPs) was primarily related to binding and catalytic activity, and that the biological functions in which the DEPs are involved included metabolism, organismal systems, cellular processes, genetic information processing, environmental information processing, and diseases. Among the disease-related functions, certain anti-viral pathways and proteins, such as the RIG-I-like receptor, Rap1, autophagy, mitogen-activated protein kinase, PI3K-Akt and Jak-STAT signaling pathways, and integrin ?2/?3 and cystatin-C proteins, represented potential factors in PEDV infection. Our findings provide valuable insight into PEDV-Vero E6 cell interactions. PMID:25783682

Sun, Dongbo; Shi, Hongyan; Guo, Donghua; Chen, Jianfei; Shi, Da; Zhu, Qinghe; Zhang, Xin; Feng, Li

2015-06-15

49

Pathogenicity and Persistence of Pleural Effusion Disease Virus Isolates in Rabbits  

Microsoft Academic Search

SUMMARY Nine isolates of pleural effusion disease agent or virus (PEDV) from treponema- infected rabbits in various countries were examined for pathogenicity and persistence in rabbits. The isolates showed a wide range of pathogenicity and were categorized into three groups according to the severity of the acute infection. Group 1 comprised isolates causing more than 50% mortality, group 2 isolates

K. L. Fennestad; B. Mansa; N. Christensen; S. Larsen; SV-E. SVEHAG

1986-01-01

50

Effects of Electromagnetic Fields on Isolated Nerve and Muscle Preparations  

Microsoft Academic Search

An S-band waveguide exposure system was designed to study the electromagnetic fields on the isolated tissues. The temperature of the exposed tissue was maintained at a constant temperature by circulating temperature controlled Ringer's solution through the waveguide. Isolated frog sciatic nerves, cat saphenous nerves, rabbit vagus nerves and superior cervical ganglia, as well as rat diaphragm muscles were placed in

Chung-Kwang Chou; ARTHUR W. GUY

1978-01-01

51

Survivability of porcine epidemic diarrhea virus (PEDV) in bovine plasma submitted to spray drying processing and held at different time by temperature storage conditions.  

PubMed

Bovine plasma was inoculated with porcine epidemic diarrhea virus (PEDV) at an average final titer of 4.2 log10 TCID50/mL to determine the effect of spray drying on viral inactivation. Using a laboratory scale drier, inoculated plasma was spray dried at 200 °C inlet temperature and either 70 or 80 °C throughout substance. Both liquid and dried samples were subjected to three passages on VERO cell monolayers to determine PEDV infectivity. Results indicated liquid samples contained infective virus, but none of the spray dried samples were infectious. Also, survivability of PEDV inoculated on spray dried bovine plasma (SDBP) and stored at 4, 12 or 22 °C was determined for 7, 14 and 21 days. Commercial SDBP powder was inoculated with PEDV to an average final titer of 2.8 log10 TCID50/g. Five samples per time and temperature conditions were subjected to three passages on VERO cell monolayers to determine PEDV infectivity. The virus was non-infectious for all samples stored at 22 °C at 7, 14 and 21 days. PEDV was infective in 1 out of 5 samples stored at 12 °C at 7 days, but none of the samples stored for 14 and 21 days were infectious in cell culture. For samples stored at 4 °C, 4 out of 5 samples were infectious at 7 days, 1 out of 5 samples were infectious at 14 days, but none were infectious at 21 days. In summary, PEDV was not infectious on cell culture within 7 days when stored at room temperature and within 21 days when stored at refrigerated temperature. PMID:25465663

Pujols, Joan; Segalés, Joaquim

2014-12-01

52

Sequence Heterogeneity of the ORF3 Gene of Porcine Epidemic Diarrhea Viruses Field Samples in Fujian, China, 2010–2012  

PubMed Central

Twenty-seven field samples that showed positive in PEDV detection were collected from different farms of Fujian province from 2010 to 2012. Their heterogeneity was investigated by analysis of the ORF3 gene because of its potential function as a representation of virulence. According to the results, six Fujian strains in Group 1 showed a different genotype with unique point mutations, which might be used in differentiation between PEDV groups and brought potential antigenic variation. P55 and five reference strains in Group 2 had a long length deletion, showing another genotype and might be involved in the variation of virulence. Phylogenetic analysis revealed that the collected Fujian strains were very distant from the vaccine development strain CV777, which might be the reason why the vaccine was inefficient to control the disease. The results can help to reconsider the strategy of PEDV vaccine management and prevent outbreaks of PEDV-induced diarrhea more efficiently. PMID:24084234

Chen, Xi; Zeng, Lili; Yang, Jinxian; Yu, Fusong; Ge, Junqing; Guo, Qing; Gao, Xindang; Song, Tieying

2013-01-01

53

Isolation, screening, and field applications of clostridial isolates to be used in microbial enhanced recovery (MEOR)  

SciTech Connect

This project concerns the isolation and screening of bacterial isolates of the genus Clostridium and their application in the field for Microbial Enhanced Oil Recovery (MEOR). Preliminary screens included growth in the presence of 860 mM sodium chloride as well as the production of metabolic end-products capable of causing a release of oil from a reservoir. Secondary screens deleted pathogenic clostrida and those that produced hydrogen sulfide. In addition, the effect of various cores on the fermentation pattern were also investigated. This involved growth of isolate SEG-3 in the presence of powdered sandstone and limestone cores. Once a number of isolates were obtained, field studies were initiated in Kansas, Oklahoma and Texas. Viable spores and a suitable nutrient were injected into producing oil wells and the fermentations monitored. A number of isolates were obtained that were capable of producing desired end-products in the presence of 860 mM sodium chloride. Field studies indicate that spores can be injected into a reservoir at pressure up to 1200 psia and survive. Complete fermentations occur in the reservoir and a biogenic gas can, to an extent, repressurize a portion of the reservoir. No detrimental effects on the oil wells were detected and although indications are that oil production can be increased no conclusions could be made.

Russell, H.H.

1988-01-01

54

Single-scaling-field approach for an isolated polymer chain  

Microsoft Academic Search

We develop an approach for describing an isolated polymer chain in solution, without appeal to the n + 0 limit of the n-vector model. Our approach treats the generating function for self-avoiding walks as a grand partition function. In this description, the fugacity per monomer plays a fundamental role as the unique scaling field in the problem. A physical picture

S. Redner; P. J. Reynolds

1981-01-01

55

Genetic diversity of Mycosphaerella graminicola isolates from a single field.  

PubMed

Septoria tritici blotch caused by Mycosphaerella graminicola is currently one of the most economically damaging diseases on wheat crops worldwide. Two hundred and sixty single-conidial isolates of this fungus were sampled in April 2012 in the Nord-Pas de Calais region (France). They have all been collected from 13 distinct plots in a single field. The corresponding isolates were then fingerprinted using 8 microsatellite markers in order to assess the genetic diversity and population structure of M. graminicola at the single field scale. The results revealed a high genotypic diversity within the collected population, with the detection of 83% of unique haplotypes among the isolates tested (clonal fraction = 17%). A high genic diversity was also found as indicated by the Nei's index value (0.50) and strong allele diversity obtained (number of alleles per locus ranged from 7 to 17, with an average of 10 alleles per locus). Further analyses showed a low population differentiation (G(ST) = 0.08) and a high gene flow (Nm = 5.64) between the 13 sampled plots. Our study suggests that sexual reproduction, by its frequency, plays a major role in the genetic diversification of M. graminicola at the field level and in the distribution and homogenization of this diversity in the field via wind-born ascospores. PMID:25151819

Siah, A; Reignault, Ph; Halama, P

2013-01-01

56

Formation, evolution and properties of isolated field elliptical galaxies  

NASA Astrophysics Data System (ADS)

We study the properties, evolution and formation mechanisms of isolated field elliptical (IfE) galaxies. We create a `mock' catalogue of IfE galaxies from the Millennium Simulation Galaxy Catalogue, and trace their merging histories. The formation, identity and assembly redshifts of simulated isolated and non-isolated elliptical galaxies are studied and compared. Observational and numerical data are used to compare age, mass and the colour-magnitude relation. Our results, based on simulation data, show that almost 7 per cent of all elliptical galaxies brighter than -19mag in B band can be classified as IfE galaxies. Results also show that isolated elliptical galaxies have a rather flat luminosity function; a number density of ~3 × 10-6h3Mpc-3mag-1, throughout their B-band magnitudes. IfE galaxies show bluer colours than non-isolated elliptical galaxies and they appear younger, in a statistical sense, according to their mass-weighted age. IfE galaxies also form and assemble at lower redshifts compared to non-isolated elliptical galaxies. About 46 per cent of IfE galaxies have undergone at least one major merging event in their formation history, while the same fraction is only ~33 per cent for non-isolated ellipticals. Almost all (~98 per cent) isolated elliptical galaxies show merging activity during their evolution, pointing towards the importance of mergers in the formation of IfE galaxies. The mean time of the last major merging is at z ~ 0.6 or 6Gyr ago for isolated ellipticals, while non-isolated ellipticals experience their last major merging significantly earlier at z ~ 1.1 or 8Gyr ago. After inspecting merger trees of simulated IfE galaxies, we conclude that three different, yet typical, formation mechanisms can be identified: solitude, coupling and cannibalism. Our results also predict a previously unobserved population of blue, dim and light galaxies that fulfil observational criteria to be classified as IfE galaxies. This separate population comprises ~26 per cent of all IfEs.

Niemi, Sami-Matias; Heinämäki, Pekka; Nurmi, Pasi; Saar, Enn

2010-06-01

57

Isolated neuron amplitude spike decrease under static magnetic fields  

NASA Astrophysics Data System (ADS)

Isolated Helix aspersa neurons under strong enough static magnetic fields B (0.07-0.7 T) show a decrease of the spike depolarization voltage of the form ?exp(?B2), with ? dependent on neuron parameters. A tentative model is proposed which explains such behaviour through a deactivation of Na+?K+-ATP-ase pumps due to protein superdiamagnetic rotation. Values for the cluster and protein in cluster numbers are estimated.

Azanza, María J.; del Moral, A.

1996-05-01

58

Field isolates of fowlpox virus contaminated with reticuloendotheliosis virus.  

PubMed

The polymerase chain reaction (PCR) method was used to examine samples from field cases of fowlpox for the presence of reticuloendotheliosis virus (REV). The S-strain fowlpox vaccine, known to be contaminated with REV, served as a positive control. Fowlpox virus was grown from field samples and vaccines by inoculation of embryonated hen eggs by the chorioallantoic membrane (CAM) route. DNA was extracted from the CAM lesions and examined for REV proviral sequences using primers specific for the long terminal repeats of REV. Amplicons of the expected length were detected in all the 45 field samples from poultry and in the S strain vaccine. Two other vaccines and two isolates from wild birds contained no detectable REV sequences. The PCR products from the vaccine and one field isolate were sequenced and were identical. These products showed 81 to 87.5% homology with the published sequences for the long terminal repeats of REV. It was not determined whether the REV proviral DNA was integrated with cellular DNA, fowlpox DNA or both. Inoculation of day-old chickens with the S-strain vaccine resulted not only in the production of fowlpox lesions but also feathering defects and proventriculitis. This suggests that the REV present in the vaccine is replication competent. Problems being encountered with protection from fowlpox following vaccination in Australia might be attributed to simultaneous challenge with fowlpox virus and REV. PMID:18483965

Diallo, I S; Mackenzie, M A; Spradbrow, P B; Robinson, W F

1998-01-01

59

Archaeoglobus fulgidus Isolated from Hot North Sea Oil Field Waters  

PubMed Central

A hyperthermophilic sulfate reducer, strain 7324, was isolated from hot (75°C) oil field waters from an oil production platform in the Norwegian sector of the North Sea. It was enriched on a complex medium and isolated on lactate with sulfate. The cells were nonmotile, irregular coccoid to disc shaped, and 0.3 to 1.0 ?m wide. The temperature for growth was between 60 and 85°C with an optimum of 76°C. Lactate, pyruvate, and valerate plus H2 were utilized as carbon and energy sources with sulfate as electron acceptor. Lactate was completely oxidized to CO2. The cells contained an active carbon monoxide dehydrogenase but no 2-oxoglutarate dehydrogenase activity, indicating that lactate was oxidized to CO2 via the acetyl coenzyme A/carbon monoxide dehydrogenase pathway. The cells produced small amounts of methane simultaneously with sulfate reduction. F420 was detected in the cells which showed a blue-green fluorescence at 420 nm. On the basis of morphological, physiological, and serological features, the isolate was classified as an Archaeoglobus sp. Strain 7324 showed 100% DNA-DNA homology with A. fulgidus Z, indicating that it belongs to the species A. fulgidus. Archaeoglobus sp. has been selectively enriched and immunomagnetically captured from oil field waters from three different platforms in the North Sea. Our results show that strain 7324 may grow in oil reservoirs at 70 to 85°C and contribute to hydrogen sulfide formation in this environment. Images PMID:16349231

Beeder, Janiche; Nilsen, Roald Kåre; Rosnes, Jan Thomas; Torsvik, Terje; Lien, Torleiv

1994-01-01

60

Pathogenesis of porcine epidemic diarrhea virus isolate (US/Iowa/18984/2013) in 3-week-old weaned pigs.  

PubMed

Porcine epidemic diarrhea virus (PEDV) is associated with clinical diarrhea in naïve swine of all ages. This report describes timing of antibody generation and disease progression following infection with a US PEDV isolate by assessing fecal viral shedding, morphometric analysis of intestinal lesions, and magnitude of immunohistochemical staining. Sixty-three, 3-week-old pigs were randomly allocated into control (n=27) and challenged (n=36) groups. Challenged pigs were administered 1 mL of 1 × 10(3) PFU/mL of US/Iowa/18984/2013 PEDV isolate by oro-gastric gavage. Three control and four challenged pigs were necropsied on days post-inoculation (dpi) 1, 2, 3, 4, 7, and weekly thereafter, until study termination on dpi 35. Clinical disease, fecal shedding, body weight, and temperature were monitored during the study period. Diarrhea was observed in challenged pigs beginning for some on dpi 2, affecting a majority of pigs by dpi 6 and subsiding by dpi 10. Average daily gain was significantly lower (P<0.001) for one week post-infection in challenged pigs. PEDV was detected in feces by PCR on dpi 1 and continued in a subset of pigs until dpi 24. PEDV-specific antigen was detected in villous enterocytes of challenged pigs by immunohistochemistry (IHC) on dpi 1, 2, 3, 4, 7, and 14. Microscopic lesions included severe diffuse atrophic enteritis with significantly reduced (P<0.001) villous length observed on dpi 3, 4, and 7. Under the conditions of this study, fecal shedding of PEDV and IHC staining can precede and continue beyond the observation of clinical signs, thus increasing the risk of viral transmission. PMID:25278366

Madson, D M; Magstadt, D R; Arruda, P H E; Hoang, H; Sun, D; Bower, L P; Bhandari, M; Burrough, E R; Gauger, P C; Pillatzki, A E; Stevenson, G W; Wilberts, B L; Brodie, J; Harmon, K M; Wang, C; Main, R G; Zhang, J; Yoon, K J

2014-11-01

61

Concentration- and time-response characteristics of plaque isolates of Agrotis ipsilon multiple nucleopolyhedrovirus derived from a field isolate  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plaque isolates derived from the Illinois field isolate of Agrotis ipsilon multiple nucleopolyhedrovirus are distinguished by the presence or absence of a small deletion in the baculovirus egt (ecdysteroid UDP-glucosyltransferase) coding sequence. Dose-response and time-response bioassays were perf...

62

Development and evaluation of enzyme-linked immunosorbent assay based on recombinant nucleocapsid protein for detection of porcine epidemic diarrhea (PEDV) antibodies  

Microsoft Academic Search

An enzyme-linked immunosorbent assays (ELISA) based on recombinant nucleocapsid (N) protein generated in Escherichia coli was evaluated for its sensitivity and specificity for diagnosis of porcine epidemic diarrhea (PEDV) infection. The N gene encoding the N protein was cloned and expressed as a fusion protein with His tag protein in E. coli. The recombinant N protein was migrated at 48kDa

Xi-Lin Hou; Li-Yun Yu; Jianzhu Liu

2007-01-01

63

An ELISA for detection of antibodies against porcine epidemic diarrhoea virus (PEDV) based on the specific solubility of the viral surface glycoprotein.  

PubMed

Viral proteins of porcine epidemic diarrhoea virus (PEDV) were extracted from the cytoplasm of infected Vero cells using hypotonic conditions and a non-ionic detergent. Both the pH and the NaCl concentration of the extraction buffer were varied in attempts to increase the solubility of the virion spike glycoproteins (S-protein) and of the nucleocapsid proteins (N-protein). Monoclonal antibodies, hyperimmune sera and convalescent pig sera were used to identify and monitor these proteins by immunoprecipitation and Western blots. The solubility of the S-protein was optimal at pH 4, whereas that of the N-protein was optimal at pH 9. Consequently, it was possible to enrich for either S-protein or N-protein; increases in the NaCl concentration of the buffer were of no advantage in this respect. Enriched preparations of the S-protein and N-protein were used as ELISA antigen for the S-ELISA and N-ELISA, respectively. The S-ELISA proved to be the more effective of the two immunoassays. Antibodies against S-protein remained detectable for longer periods of time than anti-N-protein antibodies in the sera of PEDV-infected pigs. Using this ELISA of increased sensitivity, it was observed that only a small number of farms in Switzerland had been infected with PEDV. PMID:1441196

Knuchel, M; Ackermann, M; Müller, H K; Kihm, U

1992-09-01

64

Permanent-magnet Faraday isolator with the field intensity of 25 kOe  

SciTech Connect

A Faraday isolator with a single magneto-optical element is constructed and experimentally tested. It provides the isolation ratio of 30 dB at an average laser radiation power of 650 W. These parameters are obtained by increasing the field intensity in the magnetic system of the isolator and employing a low-absorption magneto-optical element. (elements of laser devices)

Mironov, E A; Snetkov, I L; Voitovich, A V; Palashov, O V [Institute of Applied Physics, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation)

2013-08-31

65

A major gene for resistance to carbendazim, in field isolates of Gibberella zeae  

Microsoft Academic Search

Isolates of Gibberella zeae were collected from wheat fields at two sites in China. A total of 56 isolates were characterized for their ability to grow on the potato sucrose agar amended with various concentrations of carbendazim. Three sensitivity levels were identified among the isolates tested: sensitive (S) isolates could grow at 0.5 ?g·mL, but were completely inhibited at 1.4

Shankui Yuan; Mingguo Zhou

2005-01-01

66

Expression and Purification of the scFv from hybridoma cells secreting a monoclonal antibody against S PROTEIN of PEDV.  

PubMed

The variable regions of the heavy chain (VH) and light chain (VL) were amplified by RT-PCR from the hybridoma 6E6, which secretes the monoclonal antibody against PEDV S protein. The VL and VH amplicons were combined using SOE-PCR by a 12 amino acid flexible linker (SSGGGGSGGGGS), which produced the scFv gene (named scFv/6E6). After sequence analysis, the scFv/6E6 gene was cloned into the prokaryotic expression vector pGEX-6p-1 with a GST-tag. The recombinant scFv/6E6 protein was successfully expressed in recombinant Escherichia coli by IPTG induction. Moreover, the recombinant scFv/6E6 protein was purified from the inclusion body form by the gel-cutting measure followed by electroelution and dialysis. The recombinant scFv/6E6 protein reported here will provide some basis for further antiviral drug research based on the scFv molecule. PMID:23600505

Zhu, Qinghe; Guo, Donghua; Feng, Li; Sun, Dongbo

2013-02-01

67

Expression and Purification of the scFv from Hybridoma Cells Secreting a Monoclonal Antibody Against S Protein of PEDV  

PubMed Central

The variable regions of the heavy chain (VH) and light chain (VL) were amplified by RT-PCR from the hybridoma 6E6, which secretes the monoclonal antibody against PEDV S protein. The VL and VH amplicons were combined using SOE-PCR by a 12 amino acid flexible linker (SSGGGGSGGGGS), which produced the scFv gene (named scFv/6E6). After sequence analysis, the scFv/6E6 gene was cloned into the prokaryotic expression vector pGEX-6p-1 with a GST-tag. The recombinant scFv/6E6 protein was successfully expressed in recombinant Escherichia coli by IPTG induction. Moreover, the recombinant scFv/6E6 protein was purified from the inclusion body form by the gel-cutting measure followed by electroelution and dialysis. The recombinant scFv/6E6 protein reported here will provide some basis for further antiviral drug research based on the scFv molecule. PMID:23600505

Zhu, Qinghe; Guo, Donghua; Feng, Li

2013-01-01

68

A New Record of Pseudallescheria boydii Isolated from Crop Field Soil in Korea  

PubMed Central

Pseudallescheria boydii KNU13-2 was isolated from crop field soil and identified by analysis of internal transcribed spacer regions of rDNA and morphological characteristics. In the literature, P. boydii has been mentioned as a human pathogen. This is the first record of P. boydii isolated from crop field soil in Korea. PMID:25606013

Babu, A. Giridhar; Kim, Sang Woo; Yadhav, Dil Raj; Adhikari, Mahesh; Kim, Changmu; Lee, Hyang Burm

2014-01-01

69

Characterization of Isolates of Meloidogyne from Rice-Wheat Production Fields in Nepal  

PubMed Central

Thirty-three isolates of root-knot nematode were recovered from soil samples from rice-wheat fields in Nepal and maintained on rice cv. BR 11. The isolates were characterized using morphology, host range and DNA sequence analyses in order to ascertain their identity. Results indicated phenotypic similarity (juvenile measurements, perennial pattern, host range and gall shape) of the Nepalese isolates with Meloidogyne graminicola, with minor variations. The rice varieties LA 110 and Labelle were susceptible to all of the Nepalese isolates, but differences in the aggressiveness of the isolates were observed. Phylogenetic analyses based on the sequences of partial internal transcribed spacer (ITS) of the rRNA genes indicated that all Nepalese isolates formed a distinct clade with known isolates of M. graminicola with high bootstrap support. Furthermore, two groups were identified within the M. graminicola clade. No correlation between ITS haplotype and aggressiveness or host range was found among the tested isolates. PMID:19259491

Pokharel, Ramesh R.; Abawi, George S.; Zhang, Ning; Duxbury, John M.; Smart, Christine D.

2007-01-01

70

Properties of whey protein isolate–dextran conjugate prepared using pulsed electric field  

Microsoft Academic Search

Effect of pulsed electric field treatment on whey protein isolate–dextran conjugation in aqueous solution via Maillard reaction was investigated. Significant changes in browning intensity, free amino group content and SDS-PAGE profile showed that whey protein isolate–dextran conjugate was successfully formed using pulsed electric field treatment. Moreover, higher pulsed electric field intensity enhanced the extent of glycosylation. Meanwhile, the secondary structure

Wei-Wei Sun; Shu-Juan Yu; Xin-An Zeng; Xiao-Quan Yang; Xiao Jia

2011-01-01

71

Differentiation of a Vero cell adapted porcine epidemic diarrhea virus from Korean field strains by restriction fragment length polymorphism analysis of ORF 3  

Microsoft Academic Search

A porcine epidemic diarrhea virus (PEDV) designated DR13 was isolated in Vero cells and serially passaged by level 100. The virus was titrated at regular intervals of the passage level. Open reading frame (ORF) 3 sequences of the virus at passage levels 20, 40, 60, 80, and 100 were aligned and compared using a computer software program. Suitability of the

D. S Song; J. S Yang; J. S Oh; J. H Han; B. K Park

2003-01-01

72

Molecular characterization of field azoxystrobin-resistant isolates of Botrytis cinerea  

Microsoft Academic Search

Sensitivity of 184 Botrytis cinerea field isolates to a Qo inhibitor (QoI) fungicide azoxystrobin was determined in this study. Among the 184 isolates, seven showed resistance to azoxystrobin. All these seven azoxystrobin-resistant (AR) isolates were also resistant to a benzimidazole fungicide carbendazim, and a dicarboximide fungicide iprodione. Negative cross-resistance between azoxystrobin and a carboxamide fungicide boscalid was not observed in

Jinhua Jiang; Laisong Ding; Themis J. Michailides; Hongye Li; Zhonghua Ma

2009-01-01

73

A New Record of Volutella ciliata Isolated from Crop Field Soil in Korea  

PubMed Central

During a survey of fungal species in South Korea, a species of Volutella ciliata was isolated and described based on the analysis of the internal transcribed spacer region of its rDNA and its morphological characteristics. This is the first record of Volutella ciliata isolated from crop field soil in Korea.

Babu, Anam Giridhar; Kim, Sang Woo; Yadav, Dil Raj; Adhikari, Mahesh; Kim, Changmu; Lee, Hyang Burm

2015-01-01

74

Characterisation of two triple resistant field isolates of Teladorsagia from Scottish lowland sheep farms  

Microsoft Academic Search

The anthelmintic resistance status of two field isolates derived from farms (farm A and B) located near Edinburgh were examined using both controlled efficacy tests (CET) and faecal egg count reduction tests (FECRT). Efficacies against fenbendazole (FBZ), levamisole (LEV) and ivermectin (IVM) and, for one isolate, against combinations of these anthelmintics and moxidectin were determined in naïve lambs, artificially infected

D. J. Bartley; F. Jackson; E. Jackson; N. Sargison

2004-01-01

75

FIELD REACTION OF GUARDIAN PEACH ROOTSTOCK TO TWO DIFFERENT ROOT-KNOT NEMATODE ISOLATES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Advance lines of Guardian (i.e., SL 2891 and SC 3-17-7) and Lovell peach rootstocks were evaluated for their susceptibility and growth response to Meloidogyne incognita (GA-peach isolate) and M. javanica (NC-tobacco isolate) 23 months after inoculation in field microplots. Results indicate that the...

76

Molecular-genetic analysis of field isolates of Avian Leucosis Viruses in the Russian Federation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Commercial poultry farms in 14 regions of Russian Federation were monitored for avian leukosis virus (ALV) infection using virus isolation tests and serology. Results indicated the presence of two subgroups of ALV in farms located in 11 of 14 regions. Analysis of the genomes of 12 field isolates of...

77

Comparative Analysis of the Genomes of Two Field Isolates of the Rice Blast Fungus Magnaporthe oryzae  

PubMed Central

Rice blast caused by Magnaporthe oryzae is one of the most destructive diseases of rice worldwide. The fungal pathogen is notorious for its ability to overcome host resistance. To better understand its genetic variation in nature, we sequenced the genomes of two field isolates, Y34 and P131. In comparison with the previously sequenced laboratory strain 70-15, both field isolates had a similar genome size but slightly more genes. Sequences from the field isolates were used to improve genome assembly and gene prediction of 70-15. Although the overall genome structure is similar, a number of gene families that are likely involved in plant-fungal interactions are expanded in the field isolates. Genome-wide analysis on asynonymous to synonymous nucleotide substitution rates revealed that many infection-related genes underwent diversifying selection. The field isolates also have hundreds of isolate-specific genes and a number of isolate-specific gene duplication events. Functional characterization of randomly selected isolate-specific genes revealed that they play diverse roles, some of which affect virulence. Furthermore, each genome contains thousands of loci of transposon-like elements, but less than 30% of them are conserved among different isolates, suggesting active transposition events in M. oryzae. A total of approximately 200 genes were disrupted in these three strains by transposable elements. Interestingly, transposon-like elements tend to be associated with isolate-specific or duplicated sequences. Overall, our results indicate that gain or loss of unique genes, DNA duplication, gene family expansion, and frequent translocation of transposon-like elements are important factors in genome variation of the rice blast fungus. PMID:22876203

Li, Zhigang; Hu, Songnian; Yao, Nan; Dean, Ralph A.; Zhao, Wensheng; Shen, Mi; Zhang, Haiwang; Li, Chao; Liu, Liyuan; Cao, Lei; Xu, Xiaowen; Xing, Yunfei; Hsiang, Tom; Zhang, Ziding; Xu, Jin-Rong; Peng, You-Liang

2012-01-01

78

Pulsed-Field Gel Electrophoresis Diversity of Human and Bovine Clinical Salmonella Isolates  

PubMed Central

Abstract Pulsed-field gel electrophoresis (PFGE) characterization of 335 temporally and spatially matched clinical, bovine, and human Salmonella enterica subsp. enterica isolates revealed 167 XbaI PFGE patterns. These isolates were previously classified into 51 serotypes and 73 sequence types, as determined by multilocus sequence typing. Discriminatory power of PFGE (Simpson's index, D?=?0.991) was considerably higher than that of multilocus sequence typing (D?=?0.920) or serotyping (D?=?0.913). Although 128 PFGE types each only represented a single isolate, 8 PFGE types represented >4 isolates, including (i) three serotype Enteritidis and Heidelberg patterns that were only identified among human isolates, (ii) two PFGE patterns (each representing serotypes Bardo and Newport) that were significantly more common among bovine isolates as compared with human isolates; (iii) two PFGE types that each includes two serotypes (4,5,12:i:- and Typhimurium; Thompson and 1,7:-:1,5); and (iv) one PFGE type that includes eight Typhimurium isolates from humans and cattle. Characterization of isolates collected over multiple farm visits indicated that given specific PFGE types persisted over time on 11 farms. On an additional seven farms, isolates with a given sequence type represented multiple PFGE type, which typically only differed by <3 bands, suggesting PFGE type diversification during strain persistence. Sixteen PFGE types were isolated from 2 or more farms, including two widely distributed serotype Newport-associated PFGE types each found on 10 farms. In six instances two or three human isolates collected in the same county in the same or consecutive months represented the same subtypes, suggesting small human case clusters. PFGE-based characterization and surveillance of human and animal isolates can provide improved understanding of Salmonella diversity and epidemiology, including identification of possible host-associated and common, widely distributed PFGE types. PMID:20180633

Soyer, Ye?im; Alcaine, Samuel D.; Schoonmaker-Bopp, Dainna J.; Root, Timothy P.; Warnick, Lorin D.; McDonough, Patrick L.; Dumas, Nellie B.; Gröhn, Yrjo T.

2010-01-01

79

Experimental comparison of hemolytic and nonhemolytic Ornithobacterium rhinotracheale field isolates in vivo.  

PubMed

Ornithobacterium rhinotracheale (ORT) is a nonhemolytic, gram-negative, pleomorphic, rod-shaped bacterium that causes upper and lower respiratory tract disease in poultry. Recently, hemolytic strains of ORT have been isolated with increasing frequency from field outbreaks. A study was conducted to determine whether the hemolytic phenotype is associated with any change in virulence. Briefly, 225 turkey poults, vaccinated against hemorrhagic enteritis at 4 wk of age, were randomly divided into nine replicates housed in separate rooms: three sham treatment controls (25 poults/replicate), three challenged with a nonhemolytic (NH) field isolate (24 poults/replicate), and three challenged with a hemolytic (H) field isolate (24 poults/replicate). Nine days postvaccination, poults were inoculated intratracheally with either 0.2 ml sterile phosphate-buffered saline (PBS), 2 x 10(8) colony-forming units (CFU) of the NH isolate in 0.2 ml PBS, or 2 x 10(8) CFU of the H isolate in 0.2 ml PBS. Serum and body weights were obtained at 0, 7, 14, and 21 days postinoculation (dpi). Tissues were taken for culture and histopathology from five randomly selected poults/replicates at 7, 14, and 21 dpi. When compared with poults inoculated with the H isolate or controls, those inoculated with the NH isolate showed a highly significant depression in weight gain at 7 dpi. NH poults also had significantly higher levels of antibody against ORT at 14 and 21 dpi. Reisolations decreased over time and, by 21 dpi, only the NH phenotype could be found. Based on a Likert-type scale, poults inoculated with the NH isolate had significantly higher histopathologic lesion scores in lung tissue at 7, 14, and 21 dpi. Results suggest that nonhemolytic field isolates are more virulent then hemolytic ones. These findings are unusual because hemolytic phenotypes are often more virulent in other bacterial species. PMID:24758117

Walters, J; Evans, R; LeRoith, T; Sriranganathan, N; McElroy, A; Pierson, F W

2014-03-01

80

Isolation and Expulsion of Divergences in Quantum Field Theory  

E-print Network

Divergences that arise in the quantization of scalar quantum field models by means of a lattice-space functional integration may be attributed to a single integration variable, and this fact is demonstrated by showing that if the integrand for that single integration variable is appropriately changed, then a perturbation expansion becomes order-by-order finite and divergence free. The paper concludes with a brief review of a current proposal of how an auxiliary, nonclassical potential added to the lattice action of a relativistic scalar field quantization may automatically render an analogous change of the integrand, and thus may lead, as well, to nontrivial and divergence-free results.

John R. Klauder

1995-10-11

81

Lack of an effect of static magnetic field on calcium efflux from isolated chick brains  

SciTech Connect

/sup 45/Ca2+ efflux from neonatal isolated chick brains was measured. The brains were exposed to uniform or nonuniform static magnetic fields. The field intensity ranged from 200-900 mT. The exposure took place during incubation and/or when efflux was being measured. No difference appeared in the /sup 45/Ca2+ efflux between controls and exposed brains.

Bellossi, A.

1986-01-01

82

Genetic Variability of Aspergillus flavus Isolates from a Mississippi Corn Field  

PubMed Central

A nontoxigenic Aspergillus flavus strain, K49, is currently being tested as a biological control agent in corn fields in the Mississippi Delta. However, little is known about the overall genetic diversity of A. flavus from year to year in corn fields and specifically in Mississippi. Our objective was to assess the genetic variability of A. flavus isolates from different seasons, inoculum sources, and years, from a no-till corn field. Of the 175 A. flavus isolates examined, 74 and 97 had the typical norB-cypA type I (1.5?kb) and type II (1.0?kb) deletion patterns, respectively. Variability in the sequence of the omtA gene of the majority of the field isolates (n = 118) was compared to strain K49. High levels of haplotypic diversity (24 omtA haplotypes; Hd = 0.61 ± 0.04) were found. Among the 24 haplotypes, two were predominant, H1 (n = 71), which consists of mostly toxigenic isolates, and H49 (n = 18), which consists of mostly atoxigenic isolates including K49. Toxigenic isolates were prevalent (60%) in this natural population. Nonetheless, about 15% of the population likely shared the same ancestral origin with K49. This study provides valuable information on the diversity of A. flavus. This knowledge can be further used to develop additional biological control strains. PMID:25478591

Solorzano, Cesar D.; Abbas, Hamed K.; Zablotowicz, Robert M.; Chang, Perng-Kuang; Jones, Walker A.

2014-01-01

83

Multilocus Sequence Typing Scheme versus Pulsed-Field Gel Electrophoresis for Typing Mycobacterium abscessus Isolates  

PubMed Central

Outbreaks of infections by rapidly growing mycobacteria following invasive procedures, such as ophthalmological, laparoscopic, arthroscopic, plastic, and cardiac surgeries, mesotherapy, and vaccination, have been detected in Brazil since 1998. Members of the Mycobacterium chelonae-Mycobacterium abscessus group have caused most of these outbreaks. As part of an epidemiological investigation, the isolates were typed by pulsed-field gel electrophoresis (PFGE). In this project, we performed a large-scale comparison of PFGE profiles with the results of a recently developed multilocus sequence typing (MLST) scheme for M. abscessus. Ninety-three isolates were analyzed, with 40 M. abscessus subsp. abscessus isolates, 47 M. abscessus subsp. bolletii isolates, and six isolates with no assigned subspecies. Forty-five isolates were obtained during five outbreaks, and 48 were sporadic isolates that were not associated with outbreaks. For MLST, seven housekeeping genes (argH, cya, glpK, gnd, murC, pta, and purH) were sequenced, and each isolate was assigned a sequence type (ST) from the combination of obtained alleles. The PFGE patterns of DraI-digested DNA were compared with the MLST results. All isolates were analyzable by both methods. Isolates from monoclonal outbreaks showed unique STs and indistinguishable or very similar PFGE patterns. Thirty-three STs and 49 unique PFGE patterns were identified among the 93 isolates. The Simpson's index of diversity values for MLST and PFGE were 0.69 and 0.93, respectively, for M. abscessus subsp. abscessus and 0.96 and 0.97, respectively, for M. abscessus subsp. bolletii. In conclusion, the MLST scheme showed 100% typeability and grouped monoclonal outbreak isolates in agreement with PFGE, but it was less discriminative than PFGE for M. abscessus. PMID:24899019

Machado, Gabriel Esquitini; Matsumoto, Cristianne Kayoko; Chimara, Erica; Duarte, Rafael da Silva; de Freitas, Denise; Palaci, Moises; Hadad, David Jamil; Lima, Karla Valéria Batista; Lopes, Maria Luiza; Ramos, Jesus Pais; Campos, Carlos Eduardo; Caldas, Paulo César; Heym, Beate

2014-01-01

84

Evaluation of immune effects of fowlpox vaccine strains and field isolates.  

PubMed

The immune effects of fowlpox virus (FPV) field isolates and vaccine strains were evaluated in chickens infected at the age of 1 day and 6 weeks. The field isolates and the obsolete vaccine strain (FPV S) contained integrated reticuloendotheliosis virus (REV) provirus, while the current vaccine strain (FPVST) carries only REV LTR sequences. An indirect antibody ELISA was used to measure the FPV-specific antibody response. The non-specific humoral response was evaluated by injection of two T-cell-dependent antigens, sheep red blood cells (SRBC) and bovine serum albumin (BSA). There was no significant difference in the antibody response to FPV between chickens infected with FPV various isolates and strains at either age. In contrast, antibody responses to both SRBC and BSA were significantly lower in 1-day-old chickens inoculated with field isolates and FPV S at 2-3 weeks post-inoculation. Furthermore, cell-mediated immune (CMI) responses measured by in vitro lymphocyte proliferation assay and in vivo using a PHA-P skin test were significantly depressed in chickens inoculated with field isolates and FPV S at the same periods. In addition, thymus and bursal weights were lower in infected chickens. These immunosuppressive effects were not observed in chickens inoculated with the current vaccine strain, FPVST, at any time. The results of this study suggest that virulent field isolates and FPV S have immunosuppressive effects when inoculated into young chickens, which appeared in the first 3 weeks post infection. REV integrated in the FPV field isolates and FPV S may have played a central role in the development of immunosuppression. PMID:16650660

Wang, Jianning; Meers, Joanne; Spradbrow, Peter B; Robinson, Wayne F

2006-08-25

85

Oligonucleotide fingerprinting detects genetic diversity among Ascochyta rabiei isolates from a single chickpea field in Tunisia  

Microsoft Academic Search

Fifty isolates of Ascochyta rabiei (Pass.) Labr. were hierarchically sampled from four well-separated locations of a single chickpea field in Beja (Tunisia), and single-spored. DNA was isolated from in-vitro-grown mycelia, digested with HinfI or RsaI, and hybridized to a set of synthetic oligonucleotides complementary to simple repetitive sequences. According to the fingerprint patterns derived from the probes (CA)8, (CAA)5, (CAT)5

Hichem Morjane; Jtirg Geistlinger; Moncef Harrabi; Kurt Weising; Giinter Kahl

1994-01-01

86

Identification of Armillaria field isolates using isozymes and mycelial growth characteristics.  

PubMed

This research was conducted to develop procedures based on mycelial growth characteristics and patterns of esterase (EST) and polyphenol oxidase (PPO) production by diffuse mycelia for identification of Armillaria field isolates from Quercus-Carya-Pinus forests in the Ozark Mountains (central USA). The 285 isolates collected were first identified by standard diploid-haploid pairing tests as A. gallica, A. mellea, or A. tabescens. A strong PPO band was diagnostic for A. gallica. All A. mellea isolates tested and 91% of the A. tabescens isolates tested were distinguished based on production of EST bands in three standardized R f ranges. A procedure based on mycelial growth and morphology on tannic acid medium (TA) at 24 degrees C and on malt extract medium (ME) at 33 degrees C correctly identified 98% of A. gallica isolates and all A. mellea and A. tabescens isolates. On TA, A. gallica grew slowest. On ME, A. mellea grew slowest: mycelial morphology differed among species; A. gallica typically stained the agar and produced an appressed/submerged growth pattern with concentric bands of decreasing hyphal density, A. mellea typically did not stain the agar and produced round mycelia with smooth margins and abundant aerial hyphae, A. tabescens typically stained the agar and grew appressed/submerged with very irregular margins and patchy hyphal density. These are the first published systems evaluating the potential for identifying Armillaria field isolates based on their mycelial growth characteristics and EST and PPO complements. PMID:16284853

Bruhn, J N; Johnson, T E; Karr, A L; Wetteroff, J J; Leininger, T D

1998-01-01

87

Molecular Characterization of Acquired Enrofloxacin Resistance in Mycoplasma synoviae Field Isolates  

PubMed Central

The in vitro activity of enrofloxacin against 73 Mycoplasma synoviae field strains isolated in Israel and Europe was determined by broth microdilution. Decreased susceptibility to enrofloxacin was identified in 59% of strains, with the MICs ranging from 1 to >16 ?g/ml. The estimated MIC50 and MIC90 values for enrofloxacin were 2 and 8 ?g/ml, respectively. Moreover, this study showed that 92% of recent Israeli field isolates (2009 to 2011) of M. synoviae have MICs of ?2 ?g/ml to enrofloxacin. Comparison of the quinolone resistance-determining regions (QRDRs) in M. synoviae isolates revealed a clear correlation between the presence of one of the amino acid substitutions Asp79-Asn, Thr80-Ala/Ile, Ser81-Pro, and Asp84-Asn/Tyr/His of the ParC QRDR and decreased susceptibility to enrofloxacin (MIC, ?1 ?g/ml). Amino acid substitutions at positions GyrA 87, GyrB 401/402, and ParE 420/454 were also identified, but there was no clear-cut correlation with susceptibility to enrofloxacin. Comparison of vlhA molecular profiles revealed the presence of 9 different genotypes in the Israeli M. synoviae field isolates and 10 genotypes in the European isolates; only one vlhA genotype (type 4) was identified in both cohorts. Based on results of vlhA molecular typing, several mechanisms for emergence and dissemination of Israeli enrofloxacin-resistant M. synoviae isolates are suggested. PMID:23612192

Gerchman, I.; Mikula, I.; Gobbo, F.; Catania, S.; Levisohn, S.

2013-01-01

88

Complete Genome Sequence of a Recombinant Porcine Epidemic Diarrhea Virus Strain from Eastern China  

PubMed Central

A field porcine epidemic diarrhea virus (PEDV) strain, JS2008, was isolated from stool samples of a piglet with acute diarrhea on a vaccinated farm in eastern China. We sequenced and analyzed the complete genome of strain JS2008, which will help increase our understanding of the molecular characteristics of the epidemic PEDV in China. PMID:23599287

Liu, Haofei; He, Kongwang; Guo, Rongli; Ni, Yanxiu; Du, Luping; Wen, Libin; Zhang, Xuehan; Yu, Zhengyu; Zhou, Junming; Mao, Aihua; Lv, Lixin; Hu, Yiyi; Yu, Yang; Zhu, Haodan; Wang, Xiaomin

2013-01-01

89

Quantitative Field Testing Heterodera glycines from Metagenomic DNA Samples Isolated Directly from Soil under Agronomic Production  

PubMed Central

A quantitative PCR procedure targeting the Heterodera glycines ortholog of the Caenorhabditis elegans uncoordinated-78 gene was developed. The procedure estimated the quantity of H. glycines from metagenomic DNA samples isolated directly from field soil under agronomic production. The estimation of H. glycines quantity was determined in soil samples having other soil dwelling plant parasitic nematodes including Hoplolaimus, predatory nematodes including Mononchus, free-living nematodes and biomass. The methodology provides a framework for molecular diagnostics of nematodes from metagenomic DNA isolated directly from field soil. PMID:24587100

Li, Yan; Lawrence, Gary W.; Lu, Shien; Balbalian, Clarissa; Klink, Vincent P.

2014-01-01

90

Characterisation of two triple resistant field isolates of Teladorsagia from Scottish lowland sheep farms.  

PubMed

The anthelmintic resistance status of two field isolates derived from farms (farm A and B) located near Edinburgh were examined using both controlled efficacy tests (CET) and faecal egg count reduction tests (FECRT). Efficacies against fenbendazole (FBZ), levamisole (LEV) and ivermectin (IVM) and, for one isolate, against combinations of these anthelmintics and moxidectin were determined in naïve lambs, artificially infected with the isolates and treated with the compounds at the manufacturers recommended dose rates. (FBZ, 5mg/kg bodyweight (BW); LEV, 7.5mg/kg BW; IVM, 0.2mg/kg BW; Moxidectin (MOX) 0.2mg/kg BW). In both field isolates, the predominant species found pre-treatment and the only species found post-treatment was Teladorsagia circumcincta. Resistance to FBZ, LEV and IVM was confirmed in CET and FECRT on farm A and to the latter two compounds on farm B, which had a history of benzimidazole resistance and where TBZ resistance was also demonstrated using an egg hatch assay (EHA). For the farm A isolate CET efficacies against FBZ; IVM; LEV; FBZ + IVM; FBZ + LEV; FBZ, LEV + IVM and MOX were 59, 60, 88, 94,93, 92 and 98%, respectively. The CET efficacies for the farm B isolate were 51% and 72% for LEV and IVM, respectively. PMID:15325045

Bartley, D J; Jackson, F; Jackson, E; Sargison, N

2004-09-01

91

Molecular Typing by Pulsed-Field Gel Electrophoresis of Spanish Animal and Human Listeria monocytogenes Isolates  

PubMed Central

A total of 153 strains of Listeria monocytogenes isolated from different sources (72 from sheep, 12 from cattle, 18 from feedstuffs, and 51 from humans) in Spain from 1989 to 2000 were characterized by pulsed-field gel electrophoresis. The strains of L. monocytogenes displayed 55 pulsotypes. The 84 animal, 51 human, and 18 feedstuff strains displayed 31, 29, and 7 different pulsotypes, respectively, indicating a great genetic diversity among the Spanish L. monocytogenes isolates studied. L. monocytogenes isolates from clinical samples and feedstuffs consumed by the diseased animals were analyzed in 21 flocks. In most cases, clinical strains from different animals of the same flock had identical pulsotypes, confirming the existence of a listeriosis outbreak. L. monocytogenes strains with pulsotypes identical to those of clinical strains were isolated from silage, potatoes, and maize stalks. This is the first study wherein potatoes and maize stalks are epidemiologically linked with clinical listeriosis. PMID:11722943

Vela, A. I.; Fernandez-Garayzabal, J. F.; Vazquez, J. A.; Latre, M. V.; Blanco, M. M.; Moreno, M. A.; de la Fuente, L.; Marco, J.; Franco, C.; Cepeda, A.; Rodriguez Moure, A. A.; Suarez, G.; Dominguez, L.

2001-01-01

92

Production of a monoclonal antibody reacted broadly with feline calicivirus field isolates.  

PubMed

A monoclonal antibody (MAb) reactive with 36 field isolates and 2 laboratory strains of feline calicivirus (FCV) was produced by immunizing mice with the mixture of FCVs. The MAb (4D7) reacted with FCVs in an enzyme-linked immunosorbent assay (ELISA), but had no neutralizing activity against the F4 strain of FCV. MAb 8G1, previously produced against the FCV F4 strain, also reacted in ELISA with all FCVs used in the present study. However, the epitopes recognized by 4D7 and 8G1 were different. Using these two MAbs and a polyclonal rabbit antibody, we attempted to develop a sandwich ELISA for detection of FCV antigen. The combination of 4D7 and the polyclonal rabbit IgG was most sensitive. Using this system, all the field isolates of FCV cultured in vitro were detected. However, among the 36 swab samples, from which FCV was isolated, 4 were negative. PMID:9524937

Tajima, T; Yoshizaki, S; Nakata, E; Tohya, Y; Ishiguro, S; Fujikawa, Y; Sugii, S

1998-02-01

93

Increased levels of thiols protect antimony unresponsive Leishmania donovani field isolates against reactive oxygen  

E-print Network

Increased levels of thiols protect antimony unresponsive Leishmania donovani field isolates against reactive oxygen species generated by trivalent antimony G. MANDAL1 , S. WYLLIE2 , N. SINGH3 , S. SUNDAR4 (Received 28 February 2007; revised 8 May 2007; accepted 10 May 2007) SUMMARY The current trend of antimony

Schnaufer, Achim

94

Evaluating the Resistance of Eimeria Spp. Field Isolates to Anticoccidial Drugs Using Three Different Indices  

PubMed Central

Background In this study, the presence of resistance to diclazuril, amprolium+ethopabate and salinomycin, representing some of the commonest anticoccidials in Iran's poultry industry, against three mixed Eimeria field isolates were investigated. Methods Three Eimeria field isolates, collected from typical broiler farms in Iran, were propagated once, inoculated to 480 broilers, comprising 30 chicks in each treatment. The non-medicated or medicated diets containing one of the above mentioned anticoccidials were provided ad-lib. Drug efficacy was determined using the Global index (GI), Anticoccidial Sensitivity Test (AST) and Optimum Anticoccidial Activity (OAA). Results None of the field isolates were fully sensitive to the selected anticoccidials. All isolates showed reduced sensitivity/partial resistance to salinomycin. Resistance to amprolium+ethopabate was evident and partial to complete resistance was recorded for diclazuril. Conclusion Limited efficacy of the selected anticoccidials is obvious. Considering the cost of continuous use of anticoccidials in the field, altering the prevention strategy and rotation of the anticoccidials with better efficacy, would prevent further economic losses induced by coccidiosis. PMID:23914236

Arabkhazaeli, F; Modrisanei, M; Nabian, S; Mansoori, B; Madani, A

2013-01-01

95

Attosecond Lighthouses: How To Use Spatiotemporally Coupled Light Fields To Generate Isolated Attosecond Pulses  

E-print Network

Attosecond Lighthouses: How To Use Spatiotemporally Coupled Light Fields To Generate Isolated experiments (e.g., in gases or dense plasmas) enables the production of attosecond lighthouses, i.e., sources a collection of single attosecond pulses in angularly well-separated light beams--an attosecond lighthouse

Paris-Sud XI, Université de

96

Optimum design of bridges with superelastic-friction base isolators against near-field earthquakes  

NASA Astrophysics Data System (ADS)

The seismic response of a multi-span continuous bridge isolated with novel superelastic-friction base isolator (S-FBI) is investigated under near-field earthquakes. The isolation system consists of a flat steel-Teflon sliding bearing and a superelastic NiTi shape memory alloy (SMA) device. Sliding bearings limit the maximum seismic forces transmitted to the superstructure to a certain value that is a function of friction coefficient of sliding interface. Superelastic SMA device provides restoring capability to the isolation system together with additional damping characteristics. The key design parameters of an S-FBI system are the natural period of the isolated, yielding displacement of SMA device, and the friction coefficient of the sliding bearings. The goal of this study is to obtain optimal values for each design parameter by performing sensitivity analyses of the isolated bridge. First, a three-span continuous bridge is modeled as a two-degrees-of-freedom with S-FBI system. A neuro-fuzzy model is used to capture rate-dependent nonlinear behavior of SMA device. A time-dependent method which employs wavelets to adjust accelerograms to match a target response spectrum with minimum changes on the other characteristics of ground motions is used to generate ground motions used in the simulations. Then, a set of nonlinear time history analyses of the isolated bridge is performed. The variation of the peak response quantities of the isolated bridge is shown as a function of design parameters. Also, the influence of temperature variations on the effectiveness of S-FBI system is evaluated. The results show that the optimum design of the isolated bridge with S-FBI system can be achieved by a judicious specification of design parameters.

Ozbulut, Osman E.; Hurlebaus, Stefan

2010-04-01

97

Genetic diversity and relationships among Venezuelan equine encephalitis virus field isolates from Colombia and Venezuela.  

PubMed

During field studies of enzootic Venezuelan equine encephalitis (VEE) viruses associated with epizootic emergence, a large number of virus isolates were made in sylvatic foci of Venezuela and Colombia. To rapidly characterize these isolates, antigenic subtypes were determined by means of immunofluorescence and by single-strand conformational polymorphism (SSCP) analysis by use of an 856-bp fragment from the P62 gene, which we used to distinguish genetic variants. Representative isolates were sequenced to assess the sensitivity of SSCP to detect genetic differences. The SSCP analysis distinguished isolates differing by as little as 1 nucleotide; overall, differences of > or = 1 nucleotide were recognized 89% of the time, and the sensitivity to distinguish strains that differed by only 1 or 4 nucleotides was 17 and 57%, respectively. Phylogenetic analyses of representative sequences showed that all recent isolates from the Catatumbo region of western Venezuela and the middle Magdalena Valley of Colombia were closely related to epizootic subtype IAB and IC strains; strains from Yaracuy and Miranda States were more distantly related. Cocirculation of the same virus genotype in both Colombian and Venezuelan foci indicated that these viruses are readily transported between enzootic regions separated by > 300 km. The SSCP analysis appears to be a simple, fast, and relatively efficient method of screening VEE virus isolates to identify meaningful genetic variants. PMID:11791968

Moncayo, A C; Medina, G M; Kalvatchev, Z; Brault, A C; Barrera, R; Boshell, J; Ferro, C; Freier, J E; Navarro, J C; Salas, R; De Siger, J; Vasquez, C; Walder, R; Weaver, S C

2001-12-01

98

Spore-Forming Thermophilic Sulfate-Reducing Bacteria Isolated from North Sea Oil Field Waters  

PubMed Central

Thermophilic sulfate-reducing bacteria were isolated from oil field waters from oil production platforms in the Norwegian sector of the North Sea. Spore-forming rods dominated in the enrichments when lactate, propionate, butyrate, or a mixture of aliphatic fatty acids (C4 through C6) was added as a carbon source and electron donor. Representative strains were isolated and characterized. The isolates grew autotrophically on H2-CO2 and heterotrophically on fatty acids such as formate, propionate, butyrate, caproate, valerate, pyruvate, and lactate and on alcohols such as methanol, ethanol, and propanol. Sulfate, sulfite, and thiosulfate but not nitrate could be used as an electron acceptor. The temperature range for growth was 43 to 78°C; the spores were extremely heat resistant and survived 131°C for 20 min. The optimum pH was 7.0. The isolates grew well in salt concentrations ranging from 0 to 800 mmol of NaCl per liter. Sulfite reductase P582 was present, but cytochrome c and desulfoviridin were not found. Electron micrographs revealed a gram-positive cell organization. The isolates were classified as a Desulfotomaculum sp. on the basis of spore formation, general physiological characteristics, and submicroscopic organization. To detect thermophilic spore-forming sulfate-reducing bacteria in oil field water, polyvalent antisera raised against antigens from two isolates were used. These bacteria were shown to be widespread in oil field water from different platforms. The origin of thermophilic sulfate-reducing bacteria in the pore water of oil reservoirs is discussed. Images PMID:16348538

Rosnes, Jan Thomas; Torsvik, Terje; Lien, Torleiv

1991-01-01

99

Genome comparison of two Magnaporthe oryzae field isolates reveals genome variations and potential virulence effectors  

PubMed Central

Background Rice blast caused by the fungus Magnaporthe oryzae is an important disease in virtually every rice growing region of the world, which leads to significant annual decreases of grain quality and yield. To prevent disease, resistance genes in rice have been cloned and introduced into susceptible cultivars. However, introduced resistance can often be broken within few years of release, often due to mutation of cognate avirulence genes in fungal field populations. Results To better understand the pattern of mutation of M. oryzae field isolates under natural selection forces, we used a next generation sequencing approach to analyze the genomes of two field isolates FJ81278 and HN19311, as well as the transcriptome of FJ81278. By comparing the de novo genome assemblies of the two isolates against the finished reference strain 70–15, we identified extensive polymorphisms including unique genes, SNPs (single nucleotide polymorphism) and indels, structural variations, copy number variations, and loci under strong positive selection. The 1.75 MB of isolate-specific genome content carrying 118 novel genes from FJ81278, and 0.83 MB from HN19311 were also identified. By analyzing secreted proteins carrying polymorphisms, in total 256 candidate virulence effectors were found and 6 were chosen for functional characterization. Conclusions We provide results from genome comparison analysis showing extensive genome variation, and generated a list of M. oryzae candidate virulence effectors for functional characterization. PMID:24341723

2013-01-01

100

Immunogenicity and protective efficacy of recombinant S1 domain of the porcine epidemic diarrhea virus spike protein.  

PubMed

Porcine epidemic diarrhea virus (PEDV) is a highly contagious enteric pathogen of swine. Acute PEDV outbreaks have continually emerged in most swine-producing Asian countries and, recently, in the United States, causing significant economic losses in the pig industry. The spike (S) protein of PEDV is a type 1 transmembrane envelope glycoprotein and consists of the S1 and S2 domains, which are responsible for virus binding and fusion, respectively. Since the S1 domain is involved in a specific high-affinity interaction with the cellular receptor and induction of neutralizing antibody in the natural host, it is a primary target for the development of effective vaccines against PEDV. In this study, a codon-optimized PEDV S1 gene containing amino acid residues 25-738 was synthesized based on a multiple alignment of the S amino acid sequences of PEDV field isolates and used to establish a stable porcine cell line constitutively expressing the PEDV S1 protein. The purified recombinant S1 protein was found to mediate highly potent antibody responses in immunized rabbits. The antibodies strongly recognized the recombinant S1 protein from cell lysates and supernatants of S1-expressing cells, whereas they bound weakly to the authentic S protein of PEDV vaccine strain SM98-1. Furthermore, a serum neutralization test revealed that the rabbit antisera completely inhibit infection of the PEDV vaccine strain at a serum dilution of 1:16. We then tested the ability of vaccination with the recombinant S1 protein to protect piglets against PEDV. Late-term pregnant sows were inoculated intramuscularly with the purified S1 protein, and the outcome was investigated in passively immunized suckling piglets after a virulent PEDV challenge. The results showed that vaccination with S1 protein efficiently protected neonatal piglets against PEDV. Our data suggest that the recombinant S1 protein shows potential as an effective and safe subunit vaccine for PED prevention. PMID:25008896

Oh, Jongsuk; Lee, Kyung-Won; Choi, Hwan-Won; Lee, Changhee

2014-11-01

101

A new spiroplasma isolate from the field cricket (Gryllus bimaculatus) in Taiwan.  

PubMed

We briefly described the morphology and transmission pathway of a Spiroplasma sp. isolated from the field cricket, Gryllus bimaculatus in Taiwan, followed by the phylogenetic analysis based on the 16S rRNA gene sequence. The cricket spiroplasma infected the hemolymph, gut, muscle tissues and tracheal cells; therefore we suggest that the pathogen invaded tissues and organs from the hemolymph through the tracheal system and the endoplasmic reticular system. Based on 16S rRNA gene sequences and the phylogeny, this spiroplasma was most closely related to Spiroplasma platyhelix (Identity=95%) isolated from the dragonfly Pachydiplax longipennis and belongs to the Ixodetis clade. PMID:24801581

Nai, Yu-Shin; Su, Ping-Yi; Hsu, Yu-Hsiang; Chiang, Ching-Hao; Kim, Jae Su; Chen, Yue-Wen; Wang, Chung-Hsiung

2014-07-01

102

Characterization and genetic analysis of field isolates of Botryotinia fuckeliana (Botrytis cinerea) resistant to dichlofluanid  

Microsoft Academic Search

Field isolates ofBotryotinia fuckeliana were collected from naturally infected plants. Their responses to the multisite fungicide dichlofluanid in mycelium growth test fell into three phenotypic classes, characterized by the following EC50 (and MIC) values inµg ml-1: sensitivity, 1–3 (6–10); low resistance, 3–10 (> 100); high resistance, 10–30 (> 100). The corresponding values obtained for these classes in a spore germination

Stefania Pollastro; Franco Faretra; Vincenzo Di Canio; Antonietta De Guido

1996-01-01

103

Comparative Analysis of Field-Isolate and Monkey-Adapted Plasmodium vivax Genomes  

PubMed Central

Significant insights into the biology of Plasmodium vivax have been gained from the ability to successfully adapt human infections to non-human primates. P. vivax strains grown in monkeys serve as a renewable source of parasites for in vitro and ex vivo experimental studies and functional assays, or for studying in vivo the relapse characteristics, mosquito species compatibilities, drug susceptibility profiles or immune responses towards potential vaccine candidates. Despite the importance of these studies, little is known as to how adaptation to a different host species may influence the genome of P. vivax. In addition, it is unclear whether these monkey-adapted strains consist of a single clonal population of parasites or if they retain the multiclonal complexity commonly observed in field isolates. Here we compare the genome sequences of seven P. vivax strains adapted to New World monkeys with those of six human clinical isolates collected directly in the field. We show that the adaptation of P. vivax parasites to monkey hosts, and their subsequent propagation, did not result in significant modifications of their genome sequence and that these monkey-adapted strains recapitulate the genomic diversity of field isolates. Our analyses also reveal that these strains are not always genetically homogeneous and should be analyzed cautiously. Overall, our study provides a framework to better leverage this important research material and fully utilize this resource for improving our understanding of P. vivax biology. PMID:25768941

Chan, Ernest R.; Barnwell, John W.; Zimmerman, Peter A.; Serre, David

2015-01-01

104

Comparative Analysis of Field-Isolate and Monkey-Adapted Plasmodium vivax Genomes.  

PubMed

Significant insights into the biology of Plasmodium vivax have been gained from the ability to successfully adapt human infections to non-human primates. P. vivax strains grown in monkeys serve as a renewable source of parasites for in vitro and ex vivo experimental studies and functional assays, or for studying in vivo the relapse characteristics, mosquito species compatibilities, drug susceptibility profiles or immune responses towards potential vaccine candidates. Despite the importance of these studies, little is known as to how adaptation to a different host species may influence the genome of P. vivax. In addition, it is unclear whether these monkey-adapted strains consist of a single clonal population of parasites or if they retain the multiclonal complexity commonly observed in field isolates. Here we compare the genome sequences of seven P. vivax strains adapted to New World monkeys with those of six human clinical isolates collected directly in the field. We show that the adaptation of P. vivax parasites to monkey hosts, and their subsequent propagation, did not result in significant modifications of their genome sequence and that these monkey-adapted strains recapitulate the genomic diversity of field isolates. Our analyses also reveal that these strains are not always genetically homogeneous and should be analyzed cautiously. Overall, our study provides a framework to better leverage this important research material and fully utilize this resource for improving our understanding of P. vivax biology. PMID:25768941

Chan, Ernest R; Barnwell, John W; Zimmerman, Peter A; Serre, David

2015-03-01

105

Forecasting the Feasibility of Implementing Isolation Perimeters Between GM and non-GM Maize Fields Under Agricultural Conditions  

NASA Astrophysics Data System (ADS)

Although spatially isolating genetically modified (GM) maize fields from non-GM maize fields is a robust on-farm strategy to keep the adventitious presence of GM material in the harvests of neighboring non-GM maize fields due to cross-fertilizations below established labeling thresholds (and thus to ensure the spatial co-existence between maize cropping systems), the practical implementation of isolation perimeters attracted little research efforts. In this study, the feasibility of implementing isolation perimeters around GM maize fields is investigated. Using Geographic Information System datasets and Monte Carlo simulations, various scenarios differing in shares and spatial distributions of GM maize were tested for various isolation perimeters in six agricultural areas in Flanders. Factors that affect the feasibility of implementing isolation perimeters are discussed.

Devos, Yann; Cougnon, Mathias; Thas, Olivier; De Clercq, Eva M.; Cordemans, Karl; Reheul, Dirk

2008-10-01

106

Measurement of weak magnetic field of corrosion current of isolated corrosion center  

NASA Astrophysics Data System (ADS)

A very small magnetic field of corrosion current, of the order of 10-4 Oe, generated by isolated zinc inclusion in a copper platelet placed in electrolyte has been measured for the first time with a highly sensitive giant magneto-impedance magnetometer. The total corrosion current of the inclusion is estimated comparing the measured magnetic field distribution with corresponding theoretical calculation. The estimated value of the total corrosion current turns out to be in reasonable agreement with that one obtained in the standard gravimetric measurement.

Bardin, I. V.; Bautin, V. A.; Gudoshnikov, S. A.; Ljubimov, B. Ya.; Usov, N. A.

2015-01-01

107

Detection and Isolation Techniques for Methanogens from Microbial Mats (in the El Tatio Geyser Field, Chile)  

NASA Astrophysics Data System (ADS)

Isolating methanogenic archea from an extreme environment such as El Tatio (high altitude, arid climate) gives insight to the methanogenic taxas able to adapt and grow under extreme conditions. The hydrothermal waters at El Tatio geyser field demonstrate extreme geochemical conditions, with discharge water from springs and geysers at local boiling temperature (85° C) with high levels of arsenic and low DIC levels. Despite these challenges, many of El Tatio’s hundred plus hydrothermal features host extensive microbial mat communities, many showing evidence of methanogenesis. When trying to isolate methanogens unique to this area, various approaches and techniques were used. To detect the presence of methanogens in samples taken from the field, dissolved methane concentrations were determined via gas chromatography (GC) analysis. Samples were then selected for culturing and most probable number (MPN) enumeration, where growth was assessed using both methane production and observations of fluorescence under UV light. PCR was used to see if the archeal DNA was apparent directly from the field, and shotgun cloning was done to determine phylogenetic affiliation. Several culturing techniques were carried out in an attempt to isolate methanogens from samples that showed evidence of methanogenesis. The slant culturing method was used because of the increased surface area for colonization combined with the relative ease of keeping anaerobic. After a few weeks, when colonies were apparent, some were aseptically selected and inoculated to observe growth in a liquid media containing ampicillin to inhibit bacterial growth. Culturing techniques proved successful after inoculation, showing a slow growth of methanogens via GC and autofluorescence. Further PCR tests and subsequent sequencing were done to confirm and identify isolates.

Pearson, E. Z.; Franks, M. A.; Bennett, P.

2010-12-01

108

Incipient Fault Detection and Isolation of Field Devices in Nuclear Power Systems Using Principal Component Analysis  

SciTech Connect

An integrated method for the detection and isolation of incipient faults in common field devices, such as sensors and actuators, using plant operational data is presented. The approach is based on the premise that data for normal operation lie on a surface and abnormal situations lead to deviations from the surface in a particular way. Statistically significant deviations from the surface result in the detection of faults, and the characteristic directions of deviations are used for isolation of one or more faults from the set of typical faults. Principal component analysis (PCA), a multivariate data-driven technique, is used to capture the relationships in the data and fit a hyperplane to the data. The fault direction for each of the scenarios is obtained using the singular value decomposition on the state and control function prediction errors, and fault isolation is then accomplished from projections on the fault directions. This approach is demonstrated for a simulated pressurized water reactor steam generator system and for a laboratory process control system under single device fault conditions. Enhanced fault isolation capability is also illustrated by incorporating realistic nonlinear terms in the PCA data matrix.

Kaistha, Nitin; Upadhyaya, Belle R. [University of Tennessee, Knoxville (United States)

2001-11-15

109

AquaPathogen X--A template database for tracking field isolates of aquatic pathogens  

USGS Publications Warehouse

AquaPathogen X is a template database for recording information on individual isolates of aquatic pathogens and is available for download from the U.S. Geological Survey (USGS) Western Fisheries Research Center (WFRC) website (http://wfrc.usgs.gov). This template database can accommodate the nucleotide sequence data generated in molecular epidemiological studies along with the myriad of abiotic and biotic traits associated with isolates of various pathogens (for example, viruses, parasites, or bacteria) from multiple aquatic animal host species (for example, fish, shellfish, or shrimp). The simultaneous cataloging of isolates from different aquatic pathogens is a unique feature to the AquaPathogen X database, which can be used in surveillance of emerging aquatic animal diseases and clarification of main risk factors associated with pathogen incursions into new water systems. As a template database, the data fields are empty upon download and can be modified to user specifications. For example, an application of the template database that stores the epidemiological profiles of fish virus isolates, called Fish ViroTrak (fig. 1), was also developed (Emmenegger and others, 2011).

Emmenegger, Evi; Kurath, Gael

2012-01-01

110

Socially flexible female choice and premating isolation in field crickets (Teleogryllus spp.).  

PubMed

Social influences on mate choice are predicted to influence evolutionary divergence of closely related taxa, because of the key role mate choice plays in reproductive isolation. However, it is unclear whether females choosing between heterospecific and conspecific male signals use previously experienced social information in the same manner or to the same extent that they do when discriminating among conspecific mates only. We tested this using two field cricket sister species (Teleogryllus oceanicus and Teleogryllus commodus), in which considerable information is known about the role of male calling song in premating isolation, in addition to the influence of acoustic experience on the development of reproductive traits. We manipulated the acoustic experience of replicate populations of both species and found, unexpectedly, that experience of male calling song during rearing did not change how accurate females were in choosing a conspecific over a heterospecific male song during playback trials. However, females with acoustic experience were considerably less responsive to male song compared with naïve females. Our results suggest that variation in the acoustic environment affects mate choice in both species, but that it may have a limited impact on premating isolation. The fact that social flexibility during interspecific mate discrimination does not appear to operate identically to that which occurs during conspecific mate discrimination highlights the importance of considering the context in which animals exercise socially flexible mating behaviours. We suggest an explanation for why social flexibility might be context dependent and discuss the consequences of such flexibility for the evolution of reproductive isolation. PMID:24330452

Bailey, N W; Macleod, E

2013-12-16

111

Device Isolation in Hybrid Field-Effect Transistors by Semiconductor Micropatterning Using Picosecond Lasers  

NASA Astrophysics Data System (ADS)

A solid-state picosecond laser is used to ablate semiconductor thin films in spatially localized areas, providing an alternative to device isolation strategies based on chemical or ion etching techniques. Field-effect transistors (FETs) of emerging organic and inorganic materials often utilize a continuous semiconductor film and an array of top-contact electrodes. Electrically isolating individual FET components from other circuit elements is essential in order to reduce parasitic capacitances and unwanted current pathways, both to improve device performance and to enable the observation of new or enhanced physical phenomena. We pattern FET arrays with ultrafast-pulse-duration (1.5 ps) and low-fluence (0.09 J cm-2) optical pulses using the fundamental wavelength (1030 nm) of an Yb-YAG laser. We investigate two representative semiconductor materials. First, zinc oxide (ZnO) is deposited onto Si /SiO2 substrates by sol-gel methods and used to create n-channel FETs with aluminum top electrodes. Isolation of individual FETs enables the clear observation of photomodulation of the FET device parameters via photoinduced electron donation from an adsorbed chromophore. The second system comprises thin-film bilayers of tellurium and organic semiconductor molecules sequentially vapor-deposited onto Si /SiO2 substrates, with gold electrodes deposited last. Charge carrier mobility is maintained for devices isolated by picosecond lasers, but leakage currents through the FET dielectric are drastically reduced.

Ireland, Robert M.; Liu, Yu; Spalenka, Josef W.; Jaiswal, Supriya; Fukumitsu, Kenshi; Oishi, Shingo; Saito, Hiroshi; Ryosuke, Mochizuki; Evans, Paul G.; Katz, Howard E.

2014-10-01

112

First clinical isolates of Cronobacter spp. (Enterobacter sakazakii) in Argentina: characterization and subtyping by pulsed-field gel electrophoresis.  

PubMed

Cronobacter species are opportunistic pathogens associated with severe infections in neonates and immunocompromised infants. From January 2009 through September 2010, two cases of neonatal infections associated with Cronobacter malonaticus and one case associated with Cronobacter sakazakii, two of them fatal, were reported in the same hospital. These are the first clinical isolates of Cronobacter spp. in Argentina. The objective of this work was to characterize and subtype clinical isolates of Cronobacter spp. in neonate patients, as well as to establish the genetic relationship between these isolates and the foodborne isolates previously identified in the country. Pulsed-field gel electrophoresis analysis showed a genetic relationship between the C. malonaticus isolates from two patients. Different results were found when the pulsed-field gel electrophoresis patterns of clinical isolates were compared with those deposited in the National Database of Cronobacter spp. PMID:24165138

Asato, Valeria C; Vilches, Viviana E; Pineda, María G; Casanueva, Enrique; Cane, Alejandro; Moroni, Mirian P; Brengi, Silvina P; Pichel, Mariana G

2013-01-01

113

Field studies on two rock phosphate solubilizing actinomycete isolates as biofertilizer sources  

NASA Astrophysics Data System (ADS)

Recently biotechnology is focusing attention on utilization of biological resources to solve a number of environmental problems such as soil fertility management. Results of microbial studies on earthworm compost in the University of Nigeria farm identified a number of rock phosphate solubilizing actinomycetes. Two of these, isclates 02 and 13, were found to be efficient rock phosphate (RP) solubilizers and fast-growing cellulolytic microbes producing extracellular hydrolase enzymes. In this preliminary field study the two microbial isolates were investigated with respect to their effects on the growth of soybean and egusi as well as their effect on the incidence of toxicity of poultry droppings. Application of these isolates in poultry manure-treated field plots, as microbial fertilizers, brought about yield increases of 43% and 17% with soybeans and 19% and 33% with egusi, respectively. Soil properties were also improved. With isolates 02 and 13, the soil available phosphorus increased at the five-leaf stage, while N-fixation in the soil increased by 45% or 11% relative to control. It was further observed that air-dried poultry manure after four days of incubation was still toxic to soybean. The toxic effect of the applied poultry manure was reduced or eliminated with microbial fertilizers 02 or 13, respectively. The beneficial effects of the microbial organic fertilizer are discussed. Justification for more intensive research on rock phosphate organic fertilizer is highlighted.

Mba, Caroline C.

1994-03-01

114

Genetic diversity demonstrated by pulsed field gel electrophoresis of Salmonella enterica isolates obtained from diverse sources in Mexico  

Technology Transfer Automated Retrieval System (TEKTRAN)

This study was conducted to determine the genetic diversity of Salmonella isolates recovered from a variety of sources using pulsed-field gel electrophoresis (PFGE) to assess their possible relatedness. Salmonella was isolated from ca. 52% of samples from a pepper var. Bell production system. A to...

115

Induction of avirulence by AVR-Pita1 in virulent U.S. field isolates of Magnaporthe oryzae  

Technology Transfer Automated Retrieval System (TEKTRAN)

The AVR-Pita1 gene, from the Chinese isolate O-137 of Magnaporthe oryzae, is an effector that determines the efficacy of the Pi-ta rice blast resistance gene. In the present study, the avirulence function of AVR-Pita1 was induced by transformation of field isolates (TM2, ZN19, B2 and B8) that origin...

116

Induction of avirulence in U.S. virulent field isolates of Magnaporthe oryzae by AVR-Pita 1  

Technology Transfer Automated Retrieval System (TEKTRAN)

The AVR-Pita1 gene, from the Chinese isolate O-137 of Magnaporthe oryzae, is an effector that determines the efficacy of the Pi-ta rice blast resistance gene. In the present study, the avirulence function of AVR-Pita1 was induced in field isolates (TM2, ZN19, B2 and B8) that originally were virule...

117

Characterization of Salmonella isolates from retail foods based on serotyping, pulse field gel electrophoresis, antibiotic resistance and other phenotypic properties  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sixteen Salmonella strains isolated from a variety of foods during 2000 and 2003, by the Florida State Department of Agriculture, were characterized by various genotypic and phenotypic tests. Among 16 isolates, 15 different serotypes were identified. Pulse-Field Gel Electrophoresis (PFGE) fingerpr...

118

Genetic polymorphism of merozoite surface protein-1 and merozoite surface protein-2 in Plasmodium falciparum field isolates from Myanmar  

Microsoft Academic Search

BACKGROUND: Merozoite surface protein-1 (MSP-1) and MSP-2 of Plasmodium falciparum are potential vaccine candidate antigens for malaria vaccine development. However, extensive genetic polymorphism of the antigens in field isolates of P. falciparum represents a major obstacle for the development of an effective vaccine. In this study, genetic polymorphism of MSP-1 and MSP-2 among P. falciparum field isolates from Myanmar was

Jung-Mi Kang; Sung-Ung Moon; Jung-Yeon Kim; Shin-Hyeong Cho; Khin Lin; Woon-Mok Sohn; Tong-Soo Kim; Byoung-Kuk Na

2010-01-01

119

Breakdown characteristics of an isolated conducting object in a uniform electric field  

NASA Technical Reports Server (NTRS)

A laboratory experiment was conducted to determine the physical processes involved in the electrical breakdown of a particular spark gap arrangement. The gap consists of an isolated conducting ellipsoid located midway between two large flat electrodes. Gradual increase of the applied electric field, E, in the gap produces corona on the ellipsoid tips followed by flashover in a leader-arc sequence. The leader phase consists of the abrupt formation of ionized channels which partially bridge the gap and then decay prior to the arc. Measurements of dE/dt and of current were made, and photographs were taken with an image converter. Experimental parameters are listed.

Grothaus, M. G.; Trost, T. F.

1986-01-01

120

Isolation and purification of {sup 14}C-atrazine metabolites from field grown sugarcane and sorghum  

SciTech Connect

Sugarcane and sorghum plants were grown in separate field plots and treated with [2,4,6-{sup 14}C]-Atrazine (according to standard agricultural practices and at levels approximating the maximum usage rate) in partial fulfillment of EPA registration requirements. Sugarcane leaves were collected just before the final (fourth) test material application and at final harvest; canes were collected only at final harvest. Atrazine and a total of 20 metabolites of atrazine, accounting for 45.1% of the total radioactive residues, were isolated and characterized from prefourth application sugarcane leaves. Sorghum forage samples were collected 30 days after treatment (30 DAT), and at silage stage; mature fodder and grain were collected at final harvest. Two additional metabolites of atrazine were isolated and characterized from 30 DAT sorghum. Flowcharts describing the extraction and fractionation procedures used for isolation and purification of selected metabolites will be presented. The mass spectra as well as proposed metabolic pathways for these metabolites will be presented in an accompanying abstract.

Ash, S.G.; Larson, J.D.; Talaat, R.E. [Corning Hazleton, Inc., Madison, WI (United States)] [and others

1996-10-01

121

The magnetic field of an isolated neutron star from X-ray cyclotron absorption lines.  

PubMed

Isolated neutron stars are highly magnetized, fast-rotating objects that form as an end point of stellar evolution. They are directly observable in X-ray emission, because of their high surface temperatures. Features in their X-ray spectra could in principle reveal the presence of atmospheres, or be used to estimate the strength of their magnetic fields through the cyclotron process, as is done for X-ray binaries. Almost all isolated neutron star spectra observed so far appear as featureless thermal continua. The only exception is 1E1207.4-5209 (refs 7-9), where two deep absorption features have been detected, but with insufficient definition to permit unambiguous interpretation. Here we report a long X-ray observation of the same object in which the star's spectrum shows three distinct features, regularly spaced at 0.7, 1.4 and 2.1 keV, plus a fourth feature of lower significance, at 2.8 keV. These features vary in phase with the star's rotation. The logical interpretation is that they are features from resonant cyclotron absorption, which allows us to calculate a magnetic field strength of 8 x 10(10) G, assuming the absorption arises from electrons. PMID:12802327

Bignami, G F; Caraveo, P A; De Luca, A; Mereghetti, S

2003-06-12

122

High-level mucosal and systemic immune responses induced by oral administration with Lactobacillus-expressed porcine epidemic diarrhea virus (PEDV) S1 region combined with Lactobacillus-expressed N protein.  

PubMed

To develop effective mucosal vaccine formulation against porcine epidemic diarrhea virus (PEDV) infection, the DNA fragments encoding spike protein immunodominant region S1 and nucleocapsid N of PEDV were inserted into pPG1 (surface-displayed) or pPG2 (secretory) plasmids followed by electrotransformation into Lactobacillus casei (Lc) to yield four recombinant strains: PG1-S1, PG2-S1, PG1-N, and PG2-N. After intragastric administration, it was observed that live Lc-expressing S1 protein combined with Lc-expressing N protein could elicit much more potent mucosal and systemic immune responses than the former alone (P < 0.001), however slightly inferior to the latter alone (P > 0.05). Furthermore, the surface-displayed mixture (PG1-S1+ PG1-N) revealed stronger immunogenicity than the secretory mixture (PG2-S1+ PG2-N) as well as PEDV-neutralizing potency in vitro (P < 0.001). On 49th day after the last immunization, splenocytes were prepared from mice immunized with surface-displayed mixture, secretory mixture and negative control to be stimulated by purified N and S protein, respectively. The results of ELISA analysis showed that N protein was capable of inducing a higher level of IL-4 (P < 0.001) and IFN-? (P < 0.001) than S1 protein in the immunized mice. Taken together, Lc-expressed N protein as molecular adjuvant or immunoenhancer was able to effectively facilitate the induction of mucosal and systemic immune responses by Lc-expressing S1 region. PMID:22134641

Liu, Di-qiu; Ge, Jun-wei; Qiao, Xin-yuan; Jiang, Yan-ping; Liu, Song-mei; Li, Yi-jing

2012-03-01

123

Genomic and epidemiological characteristics provide new insights into the phylogeographical and spatiotemporal spread of porcine epidemic diarrhea virus in Asia.  

PubMed

Porcine epidemic diarrhea has become pandemic in the Asian pig-breeding industry, causing significant economic loss. In the present study, 11 complete genomes of porcine epidemic diarrhea virus (PEDV) field isolates from China were determined and analyzed. Frequently occurring mutations were observed, which suggested that full understanding of the genomic and epidemiological characteristics is critical in the fight against PEDV epidemics. Comparative analysis of 49 available genomes clustered the PEDV strains into pandemic (PX) and classical (CX) groups and identified four hypervariable regions (V1 to V4). Further study indicated key roles for the spike (S) gene and the V2 region in distinguishing between the PX and CX groups and for studying genetic evolution. Genotyping and phylogeny-based geographical dissection based on 219 S genes revealed the complexity and severity of PEDV epidemics in Asia. Many subgroups have formed, with a wide array of mutations in different countries, leading to the outbreak of PEDV in Asia. Spatiotemporal reconstruction based on the analysis suggested that the pandemic group strains originated from South Korea and then extended into Japan, Thailand, and China. However, the novel pandemic strains in South Korea that appeared after 2013 may have originated from a Chinese variant. Thus, the serious PED epidemics in China and South Korea in recent years were caused by the complex subgroups of PEDV. The data in this study have important implications for understanding the ongoing PEDV outbreaks in Asia and will guide future efforts to effectively prevent and control PEDV. PMID:25694517

Sun, Min; Ma, Jiale; Wang, Yanan; Wang, Ming; Song, Wenchao; Zhang, Wei; Lu, Chengping; Yao, Huochun

2015-05-01

124

Complete genome sequence of a novel porcine epidemic diarrhea virus in south China.  

PubMed

Since early 2010, outbreaks of porcine epidemic diarrhea (PED) have been observed frequently in immunized swine herds in southern China. The suckling piglets are particularly susceptible to porcine epidemic diarrhea virus (PEDV), with a high mortality rate (90%). Recently, a virulent PEDV strain, GD-A, was isolated from an immunized-swine breeding farm in Guangdong, China. This report describes the complete genome sequence of GD-A, and the data will provide important insights into the variation of PEDV field isolates in southern China. PMID:22923806

Fan, Huiying; Zhang, Jie; Ye, Yu; Tong, Tiezhu; Xie, Kangshang; Liao, Ming

2012-09-01

125

Calcium homeostasis of isolated heart muscle cells exposed to pulsed high-frequency electromagnetic fields  

SciTech Connect

The intracellular calcium concentration ([Ca{sup 2+}]{sub i}) of isolated ventricular cardiac myocytes of the guinea pig was measured during the application of pulsed high-frequency electromagnetic fields. The high-frequency fields were applied in a transverse electromagnetic cell designed to allow microscopic observation of the myocytes during the presence of the high-frequency fields. The [Ca{sup 2+}]{sub i} was measured as fura-2 fluorescence by means of digital image analysis. Both the carrier frequency and the square-wave pulse-modulation pattern were varied during the experiments (carrier frequencies: 900, 1,300, and 1,800 MHz pulse modulated at 217 Hz with 14% duty cycle; pulsation pattern at 900 MHz; continuous wave, 16 Hz,and 50 Hz modulation with 50% duty cycle and 30 kHz modulation with 80% duty cycle). The mean specific absorption rate (SAR) values in the solution were within one order of magnitude of 1 mW/kg. They varied depending on the applied carrier frequency and pulse pattern. The experiments were designed in three phases: 500 s of sham exposure, followed by 500 s of field exposure, then chemical stimulation without field. The chemical stimulation (K{sup +}-depolarization) indicated the viability of the cells. The K{sup +} depolarization yielded a significant increase in [Ca{sup 2+}]{sub i}. Significant differences between sham exposure and high-frequency field exposure were not found except when a very small but statistically significant difference was detected in the case of 900 MHz/50 Hz. However, this small difference was not regarded as a relevant effect of the exposure.

Wolke, S.; Gollnick, F.; Meyer, R. [Univ. Bonn (Germany)] [Univ. Bonn (Germany); Neibig, U.; Elsner, R. [Inst. fuer Nachrichtentechnik Braunschweig (Germany)] [Inst. fuer Nachrichtentechnik Braunschweig (Germany)

1996-05-01

126

Deinococcus soli sp. nov., a gamma-radiation-resistant bacterium isolated from rice field soil.  

PubMed

A Gram-negative, non-motile, short rod-shaped bacterial strain, designated N5(T), was isolated from a rice field soil in South Korea. Phylogenetic analysis based on the 16S rRNA gene sequence of the new isolate showed that strain N5(T) belongs to the genus Deinococcus, family Deinococcaceae, showing the highest sequence similarity to Deinococcus grandis KACC 11979(T) (98.4 %) and Deinococcus daejeonensis KCTC 13751(T) (97.5 %). Strain N5(T) exhibits resistance to gamma-radiation similar to that of other members of the genus Deinococcus, with a D10 value in excess of 4 kGy. Chemotaxonomic data showed that the most abundant fatty acids are C16:1?7c (25.25 %), C15:1?6c (19.77 %), C17:1?6c (11.87 %), and C17:0 (9.41 %), and the major polar lipid is an unknown phosphoglycolipid. The predominant respiratory quinone is menaquinone MK-8. The DNA G+C content is 71.4 mol%. Phenotypic, phylogenetic, and chemotaxonomic data support designation of strain N5(T) as a novel species of the genus Deinococcus, for which the name Deinococcus soli sp. nov. is proposed. The type strain is N5(T) (=KCTC 33153(T) = JCM 19176(T)). PMID:24554344

Cha, Seho; Srinivasan, Sathiyaraj; Seo, Taegun; Kim, Myung Kyum

2014-06-01

127

{{{W}}_3} irregular states and isolated {N}=2 superconformal field theories  

NASA Astrophysics Data System (ADS)

We explore the proposal that the six-dimensional (2, 0) theory on the Riemann surface with irregular punctures leads to a four-dimensional gauge theory coupled to the isolated {N}=2 superconformal theories of Argyres-Douglas type, and to two-dimensional conformal field theory with irregular states. Following the approach of Gaiotto-Teschner for the Virasoro case, we construct {{{W}}_3} irregular states by colliding a single SU(3) puncture with several regular punctures of simple type. If n simple punctures are colliding with the SU(3) puncture, the resulting irregular state is a simultaneous eigenvector of the positive modes L n , . . . , L 2 n and W 2 n , . . . , W 3 n of the {{{W}}_3} algebra. We find the corresponding isolated SCFT with an SU(3) flavor symmetry as a nontrivial IR fixed point on the Coulomb branch of the SU(3) linear quiver gauge theories, by confirming that its Seiberg-Witten curve correctly predicts the conditions for the {{{W}}_3} irregular states. We also compare these SCFT's with the ones obtained from the BPS quiver method.

Kanno, Hiroaki; Maruyoshi, Kazunobu; Shiba, Shotaro; Taki, Masato

2013-03-01

128

Epilithonimonas ginsengisoli sp. nov., isolated from soil of a ginseng field.  

PubMed

A novel Gram-staining-negative, rod-shaped bacterium, designated DCY78(T), was isolated from soil of a ginseng field in Yeon-cheon province (38° 04' 00? N 126° 57' 00? E), Republic of Korea. The phylogenetic analysis based on 16S rRNA gene sequences showed that strain DCY78(T) belonged to the genus Epilithonimonas and was most closely related to Epilithonimonas lactis DSM 19921(T) (98.5?% sequence similarity) and Epilithonimonas tenax DSM 16811(T) (97.8?%). Growth occurred at 10-30 °C with an optimum temperature of 28 °C. The pH range for growth was pH 5.5-8.0. The major polar lipids were found to be phosphatidylethanolamine three unidentified amino lipids and one unidentified polar lipid. The only predominant quinone was MK-6. The major polyamines were sym-homospermidine and spermidine. The major fatty acids were summed feature 3 (comprising C16?:?1?6c and/or C16?:?1?7c), iso-C15?:?0 and iso-C17?:?0 3-OH. The DNA G+C content was 37.9 mol%. On the basis of the phenotypic and genotypic analysis, the isolate is classified as representative of a novel species in the genus Epilithonimonas, for which the name Epilithonimonas ginsengisoli is proposed. The type strain is DCY78(T) (?=?KCTC 32174(T)?=?JCM 19896(T)). PMID:25298379

Hoang, Van-An; Kim, Yeon-Ju; Ponnuraj, Shree Priya; Nguyen, Ngoc-Lan; Hwang, Kyu-Hyon; Yang, Deok-Chun

2015-01-01

129

Comparison of implant isolation species for GaN field-effect transistor structures  

SciTech Connect

Different ions (Ti{sup +}, O{sup +}, Fe{sup +}, Cr{sup +}) were implanted at multiple energies into GaN field effect transistor structures (n and p-type). The implantation was found to create deep states with energy levels in the range E{sub c} {minus}0.20 to 0.49 eV in n-GaN and at E{sub v} + 0.44 eV in p-GaN after annealing at 450--650 C. The sheet resistance of the GaN was at a maximum after annealing at these temperatures, reaching values of {approximately}4x10{sup 12} {Omega}/{open_square} in n-GaN and {approximately}10{sup 10}{Omega}/{open_square} in p-GaN. The mechanism for the implant isolation was damage-related trap formation for all of the ions investigated, and there was no evidence of chemically induced isolation.

Dang, G.; Cao, X.A.; Ren, F.; Pearton, S.J.; Han, J.; Baca, A.G.; Shul, R.I.; Wilson, R.G.

2000-07-01

130

Faraday isolator based on a TSAG single crystal with compensation of thermally induced depolarization inside magnetic field  

NASA Astrophysics Data System (ADS)

A Faraday isolator based on a terbium scandium aluminum garnet (TSAG) single crystal with compensation of thermally induced depolarization inside magnetic field was demonstrated. An isolation ratio of 32 dB at 350 W cw laser radiation power was achieved. Thermally induced depolarization and thermal lens were studied and compared with similar thermal effects arising in the widely used terbium gallium garnet crystal (TGG) for the first time.

Snetkov, Ilya; Palashov, Oleg

2015-04-01

131

Antibiotic resistance of Salmonella strains isolated from children living in the wastewater-spreading field of Marrakesh city (Morocco)  

Microsoft Academic Search

A total of 813 Salmonella strains isolated from raw wastewater and stool specimens of inpatient children, living in the wastewater-spreading field of Marrakesh city, were examined for their susceptibility to 15 antimicrobial agents. All the isolates were susceptible to cefotaxime, and almost of them showed susceptibility to gentamicin (99.88%), trimethoprim-sulphamethoxazole (98.04%), nalidixic acid (98.04%), kanamycin (97.30%), trimethoprim (97.18%), and chloramphenicol

A. A. Melloul; L. Hassani

1999-01-01

132

Isolation and Characterization of a Novel Facultative Anaerobic Filamentous Fungus from Japanese Rice Field Soil  

PubMed Central

A novel filamentous fungus strain designated RB-1 was isolated into pure culture from Japanese rice field soil through an anaerobic role tube technique. The strain is a mitosporic fungus that grows in both aerobic and strict anaerobic conditions using various mono-, di-, tri-, and polysaccharides with acetate and ethanol productions. The amount of acetate produced was higher than that of ethanol in both aerobic and anaerobic cultures. The characteristic verrucose or punctuate conidia of RB-1 closely resembled those of some strains of the genus Thermomyces, a thermophilic or mesophilic anamorphic ascomycete. However, based on phylogenetic analysis with the small subunit (SSU) and large subunit (LSU) rDNA sequences, RB-1 was characterized as a member of the class Lecanoromycetes of the phylum Ascomycota. Currently, RB-1 is designated as an anamorphic ascomycete and is phylogenetically considered an incertae sedis within the class Lecanoromycetes. PMID:20148171

Tonouchi, Akio

2009-01-01

133

Isolated horizons, p-form matter fields, topology, and the black-hole/string correspondence principle  

SciTech Connect

We study the mechanics of D-dimensional isolated horizons (IHs) for Einstein gravity in the presence of arbitrary p-form matter fields. This generalizes the analysis of Copsey and Horowitz to nonstationary spacetimes and therefore the local first law in D>4 dimensions to include nonmonopolar (dipole) charges. The only requirement for the local first law to hold is that the action has to be differentiable. The resulting conserved charges are all intrinsic to the horizon and are independent of the topology of the horizon cross sections. We explicitly calculate the local charges for five-dimensional black holes and black rings that are relevant within the context of superstring theory. We conclude with some comments on the black-hole/string correspondence principle and argue that IHs (or some other quasilocal variant) should play a fundamental role in superstring theory.

Liko, Tomas [Institute for Gravitation and the Cosmos, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

2009-04-15

134

Isolated horizons, p-form matter fields, topology, and the black-hole/string correspondence principle  

NASA Astrophysics Data System (ADS)

We study the mechanics of D-dimensional isolated horizons (IHs) for Einstein gravity in the presence of arbitrary p-form matter fields. This generalizes the analysis of Copsey and Horowitz to nonstationary spacetimes and therefore the local first law in D>4 dimensions to include nonmonopolar (dipole) charges. The only requirement for the local first law to hold is that the action has to be differentiable. The resulting conserved charges are all intrinsic to the horizon and are independent of the topology of the horizon cross sections. We explicitly calculate the local charges for five-dimensional black holes and black rings that are relevant within the context of superstring theory. We conclude with some comments on the black-hole/string correspondence principle and argue that IHs (or some other quasilocal variant) should play a fundamental role in superstring theory.

Liko, Tomáš

2009-04-01

135

Isolated horizons, p-form matter fields, topology and the black-hole/string correspondence principle  

E-print Network

We study the mechanics of D-dimensional isolated horizons (IHs) for Einstein gravity in the presence of arbitrary p-form matter fields. This generalizes the analysis of [K. Copsey and G. T. Horowitz Phys. Rev. D 73 024015 (2006)] to non-stationary spacetimes and therefore the local first law to include non-monopolar (dipole) charges. The only requirement for the local first law to hold is that the action has to be differentiable. The resulting conserved charges are all intrinsic to the horizon and are independent of the topology of the horizon cross sections. We explicitely calculate the local charges for five-dimensional black holes and black rings that are relevant within the context of superstring theory. We conclude with some comments on the black-hole/string correspondence principle and argue that IHs (or some other quasilocal variant) should play a fundamental role in superstring theory.

Liko, Tomas

2009-01-01

136

Isolated horizons, p-form matter fields, topology and the black-hole/string correspondence principle  

E-print Network

We study the mechanics of D-dimensional isolated horizons (IHs) for Einstein gravity in the presence of arbitrary p-form matter fields. This generalizes the analysis of Copsey and Horowitz to non-stationary spacetimes and therefore the local first law to include non-monopolar (dipole) charges. The only requirement for the local first law to hold is that the action has to be differentiable. The resulting conserved charges are all intrinsic to the horizon and are independent of the topology of the horizon cross sections. We explicitly calculate the local charges for five-dimensional black holes and black rings that are relevant within the context of superstring theory. We conclude with some comments on the black-hole/string correspondence principle and argue that IHs (or some other quasilocal variant) should play a fundamental role in superstring theory.

Tomas Liko

2009-03-25

137

Attosecond Lighthouses: How To Use Spatiotemporally Coupled Light Fields To Generate Isolated Attosecond Pulses  

NASA Astrophysics Data System (ADS)

Under the effect of even simple optical components, the spatial properties of femtosecond laser beams can vary over the duration of the light pulse. We show how using such spatiotemporally coupled light fields in high harmonic generation experiments (e.g., in gases or dense plasmas) enables the production of attosecond lighthouses, i.e., sources emitting a collection of angularly well-separated light beams, each consisting of an isolated attosecond pulse. This general effect opens the way to a new generation of light sources, particularly suitable for attosecond pump-probe experiments, and provides a new tool for ultrafast metrology, for instance, giving direct access to fluctuations of the carrier-envelope relative phase of even the most intense ultrashort lasers.

Vincenti, H.; Quéré, F.

2012-03-01

138

Molecular monitoring of antimalarial drug resistance among Plasmodium falciparum field isolates from Odisha, India.  

PubMed

In the absence of definite marker for artemisinin (ART) resistance, molecular monitoring of its partner drug sulfadoxine pyrimethamine (SP) in artemisinin based combination therapy (ACTs) together with chloroquine (CQ) for which ART is negatively correlated, may predict the effectiveness of ACT. We analyzed 201 Plasmodium falciparum field isolates for drug resistance markers for CQ (pfcrt and pfmdr1), pyrimethamine (pfdhfr) and sulfadoxine (pfdhps). Our study reveals high prevalence and non-random association of resistant mutants (K76T and N86Y) of CQ markers (pfcrt and pfmdr1). The predominance of highly resistant pfdhfr genotypes for SP with intragenic and intergenic pair-wise linkage disequilibrium between single nucleotide polymorphisms of resistant mutants of pfdhfr (C59R and S108N) and pfdhps (S436A, A437G, K540E) warn on further inclusion of SP in ACT. These findings suggest the replacement of SP in ACT with alternative partner drug for better efficacy. PMID:23357175

Das Sutar, Sasmita Kumari; Dhangadamajhi, Gunanidhi; Kar, Shantanu Kumar; Ranjit, Manoranjan

2013-04-01

139

Influence of day-length and isolates of Phytophthora infestans on field resistance to late blight of potato.  

PubMed

Main and interaction effects of day-length and pathogen isolate on the reaction and expression of field resistance to Phytophthora infestans were analyzed in a sample of standard clones for partial resistance to potato late blight, and in the BCT mapping population derived from a backcross of Solanum berthaultii to Solanum tuberosum. Detached leaves from plants grown in field plots exposed to short- and long day-length conditions were independently inoculated with two P. infestans isolates and incubated in chambers under short- and long photoperiods, respectively. Lesion growth rate (LGR) was used for resistance assessment. Analysis of variance revealed a significant contribution of genotype x isolate x day-length interaction to variation in LGR indicating that field resistance of genotypes to foliar late blight under a given day-length depended on the infecting isolate. An allele segregating from S. berthaultii with opposite effects on foliar resistance to late blight under long- and short day-lengths, respectively, was identified at a quantitative trait locus (QTL) that mapped on chromosome 1. This allele was associated with positive (decreased resistance) and negative (increased resistance) additive effects on LGR, under short- and long day-length conditions, respectively. Disease progress on whole plants inoculated with the same isolate under field conditions validated the direction of its effect in short day-length regimes. The present study suggests the occurrence of an isolate-specific QTL that displays interaction with isolate behavior under contrasting environments, such as those with different day-lengths. This study highlights the importance of exposing genotypes to a highly variable population of the pathogen under contrasting environments when stability to late blight resistance is to be assessed or marker-assisted selection is attempted for the manipulation of quantitative resistance to late blight. PMID:20063145

Mihovilovich, E; Munive, S; Bonierbale, M

2010-04-01

140

Isolation of marine bacteria with antimicrobial activities from cultured and field-collected soft corals.  

PubMed

Bacteria associated with eight field-collected and five cultured soft corals of Briareum sp., Sinularia sp., Sarcophyton sp., Nephtheidae sp., and Lobophytum sp. were screened for their abilities in producing antimicrobial metabolites. Field-collected coral samples were collected from Nanwan Bay in southern Taiwan. Cultured corals were collected from the cultivating tank at National Museum of Marine Biology and Aquarium. A total of 1,526 and 1,138 culturable, heterotrophic bacteria were isolated from wild and cultured corals, respectively; seawater requirement and antimicrobial activity were then assessed. There is no significant difference between the ratio of seawater-requiring bacteria on the wild and cultured corals. The ratio of antibiotic-producing bacteria within the seawater-requiring bacteria did not differ between the corals. Nineteen bacterial strains that showed high antimicrobial activity were selected for 16S rDNA sequencing. Three strains could be assigned at the family level (Rhodobacteraceae). The remaining 16 strains belong to eight genera: Marinobacterium (2 strains), Pseudoalteromonas (1), Vibrio (5), Enterovibrio (1), Tateyamaria (1), Labrenzia (2), and Pseudovibrio (4). The crude extract from bacteria strains CGH2XX was found to have high cytotoxicity against the cancer cell line HL-60 (IC(50) = 0.94 ?g/ml) and CCRF-CEM (IC(50) = 1.19 ?g/ml). Our results demonstrate that the marine bacteria from corals have great potential in the discovery of useful medical molecules. PMID:22872580

Chen, Yu-Hsin; Kuo, Jimmy; Sung, Ping-Jung; Chang, Yu-Chia; Lu, Mei-Chin; Wong, Tit-Yee; Liu, Jong-Kang; Weng, Ching-Feng; Twan, Wen-Hung; Kuo, Fu-Wen

2012-12-01

141

Laboratory and field evaluations for efficacy of a fast-killing baculovirus isolate from Spodoptera frugiperda  

Technology Transfer Automated Retrieval System (TEKTRAN)

Three biopesticide parameters were evaluated for a fast-killing isolate (3AP2) Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) and a wild-type isolate (Sf3) of the same baculovirus. Both isolates were evaluated for virus production using in vivo methods, for speed of kill based on bioas...

142

Determination of discriminating dose and evaluation of amitraz resistance status in different field isolates of Rhipicephalus (Boophilus) microplus in India.  

PubMed

Field tick isolates of Rhipicephalus (Boophilus) microplus were collected from eleven districts located in the northern and eastern states of India to access the resistance status to "Amitraz". Adult immersion test was optimized using laboratory reared acaricide susceptible IVRI-I line and minimum effective concentration was determined as 487.7 ppm with 95 % confidence interval of 455.8-521.8. The discriminating concentration was determined as 975.4 ppm and was tested on female ticks collected by two stage stratified sampling from organized dairy farms and villages. Based on three variables, viz.,mortality, egg masses and reproductive index, the resistance level was categorized.Resistance to amitraz was detected at level I in 3 isolates (RF = 1.56-5.0), at level II in 6 isolates (RF = 9.3-23.3) and at level III in 1 isolate (RF = 27.3) whereas one isolate was found susceptible. The highest resistance was found in the SKR isolate (RF = 27.3) and minimal resistance was detected in the N-24P isolate (RF = 1.56). These experimental data will help in designing tick control strategy which is suffering from acaricide failure and to overcome development of resistance in ticks. PMID:24659517

Kumar, Sachin; Sharma, Anil Kumar; Ray, D D; Ghosh, Srikant

2014-07-01

143

Characterization of leptospira borgpetersenii isolates from field rats (rattus norvegicus) by 16s rrna and lipl32 gene sequencing  

PubMed Central

The main goal of this study was to evaluate the prevalence of leptospirosis among field rodents of Tiruchirappalli district, Tamil Nadu, India. In total 35 field rats were trapped and tested for seroprevalence by the microscopic agglutination test (MAT). Isolation of leptospires was performed from blood and kidney tissues and characterized to serovar level. Genomospecies identification was carried out using 16S rRNA and lipL32 gene sequencing. The molecular phylogeny was constructed to find out species segregation. Seroprevalence was about 51.4 %, and the predominant serovars were Autumnalis, Javanica, Icterohaemorrhagiae and Pomona. Two isolates from the kidneys were identified as serovar Javanica of Serogroup Javanica, and sequence based molecular phylogeny indicated these two isolates were Leptospira borgpetersenii. PMID:24031475

Vedhagiri, Kumaresan; Natarajaseenivasan, Kalimuthusamy; Prabhakaran, Shanmugarajan G.; Selvin, Joseph; Narayanan, Ramasamy; Shouche, Yogesh S.; Vijayachari, Paluru; Ratnam, Sivalingam

2010-01-01

144

Isolation of exotic Newcastle disease virus (ENDV) from field collected flies and experimental ENDV infections of three arthropod species  

Technology Transfer Automated Retrieval System (TEKTRAN)

During the 2002 Exotic Newcastle Disease (END) outbreak in California arthropods were collected from two quarantined backyard poultry premises after removal of END virus infected birds. The END virus (ENDV) isolated from field collected pools of three fly species was found to have >98% homology by ...

145

Understanding the molecular mechanism of instability of the avirulence gene AVR-Pita1 in field isolates of Maganporthe oryzae  

Technology Transfer Automated Retrieval System (TEKTRAN)

The avirulence gene AVR-Pita1 in Magnaporthe oryzae triggers a resistance response in rice plants that contain the resistance gene Pi-ta. Understanding the evolution of the AVR-Pita1 gene in field isolates should benefit the deployment of Pi-ta for the control of rice blast disease. A total of 187 f...

146

Co-transmission of the non-transmissible South African Babesia bovis S24 vaccine strain during mixed infection with a field isolate.  

PubMed

The South African Babesia bovis live blood vaccine, originating from a field isolate attenuated by 23 serial syringe passages in splenectomized calves, has lost the ability to infect the natural vector Rhipicephalus (Boophilus) microplus. In this study, infection with mixed parasites from the vaccine strain and a field isolate, resulted in transmission of both genotype populations. Comparing the field isolate and transmitted combination indicated no significant difference in their virulence, while challenge of vaccinated cattle with these isolates showed the ability of the vaccine to protect against both. Limiting dilution of the transmitted combination, followed by infection of splenectomized cattle (n=34) yielded no single infections for the vaccine strain genotype, seven clonal lines of the field isolate and one mixture of vaccine strain and field isolate. Only one of two field isolate clonal lines selected for vector transmission study was transmitted. Showing that B. bovis isolates can contain both tick transmissible and non-transmissible subpopulations. The findings of this study also indicate the probability of vaccine co-infection transmission occurring in the field, which may result in new genotype populations of B. bovis. However, the impact of this recombination with field isolates is considered negligible since a genotypically diverse population of B. bovis is already present in South Africa. PMID:25544307

Combrink, M P; Troskie, P C; de Klerk, D G; Pienaar, R; Latif, A A; Mans, B J

2015-03-01

147

Field Studies Reveal Strong Postmating Isolation between Ecologically Divergent Butterfly Populations  

PubMed Central

Gene flow between populations that are adapting to distinct environments may be restricted if hybrids inherit maladaptive, intermediate phenotypes. This phenomenon, called extrinsic postzygotic isolation (EPI), is thought to play a critical role in the early stages of speciation. However, despite its intuitive appeal, we know surprisingly little about the strength and prevalence of EPI in nature, and even less about the specific phenotypes that tend to cause problems for hybrids. In this study, we searched for EPI among allopatric populations of the butterfly Euphydryas editha that have specialized on alternative host plants. These populations recall a situation thought typical of the very early stages of speciation. They lack consistent host-associated genetic differentiation at random nuclear loci and show no signs of reproductive incompatibility in the laboratory. However, they do differ consistently in diverse host-related traits. For each of these traits, we first asked whether hybrids between populations that use different hosts (different-host hybrids) were intermediate to parental populations and to hybrids between populations that use the same host (same-host hybrids). We then conducted field experiments to estimate the effects of intermediacy on fitness in nature. Our results revealed strong EPI under field conditions. Different-host hybrids exhibited an array of intermediate traits that were significantly maladaptive, including four behaviors. Intermediate foraging height slowed the growth of larvae, while intermediate oviposition preference, oviposition site height, and clutch size severely reduced the growth and survival of the offspring of adult females. We used our empirical data to construct a fitness surface on which different-host hybrids can be seen to fall in an adaptive valley between two peaks occupied by same-host hybrids. These findings demonstrate how ecological selection against hybrids can create a strong barrier to gene flow at the early stages of adaptive divergence. PMID:21048982

McBride, Carolyn S.; Singer, Michael C.

2010-01-01

148

Paenibacillus ginsengiterrae sp. nov., a ginsenoside-hydrolyzing bacteria isolated from soil of ginseng field.  

PubMed

A novel bacterial strain DCY89(T) was isolated from soil sample of ginseng field and was characterized using a polyphasic approach. Cells were Gram-reaction-positive, rod-shaped, spore-forming and motile with flagella. The strain was aerobic, esculin and starch positive, catalase- and oxidase-negative, optimum growth temperature, and pH were 25-30 °C and 6.0-7.5, respectively. On the basis of 16S rRNA gene sequence analysis, strain DCY89(T) was shown to belong to the genus Paenibacillus and the closest phylogenetic relatives were Paenibacillus cellulosilyticus KACC 14175(T) (98.2%), Paenibacillus kobensis KACC 15273(T) (98.1%), Paenibacillus xylaniclasticus KCTC 13719(T) (96.9%), and Paenibacillus curdlanolyticus KCTC 3759(T) (96.64%). The DNA G+C content was 52.5 mol%, and the predominant respiratory quinone was MK-7. The major fatty acids were iso-C15:0, iso-C16:0, and anteiso-C15:0. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol. The results of the genotypic analysis in combination with chemotaxonomic and physiological data demonstrated that DCY89(T) represented a novel species within the genus Paenibacillus, for which we propose the name Paenibacillus ginsengiterrae. The type strain is DCY89(T) (JCM 19887(T) = KCTC 33430(T)). PMID:25516431

Huq, Md Amdadul; Kim, Yeon-Ju; Hoang, Van-An; Siddiqi, Muhammad Zubair; Yang, Deok-Chun

2015-04-01

149

Agromyces arachidis sp. nov. Isolated from a Peanut (Arachis hypogaea) Crop Field  

PubMed Central

A Gram-positive, yellowish bacterium strain AK-1T was isolated from soil sample collected from peanut (Arachis hypogaea) crop field and studied by using a polyphasic approach. The organism had morphological and chemotaxonomic properties consistent with its classification in the genus Agromyces. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain AK-1T was closely related to Agromyces aurantiacus (98.6%) followed by Agromyces soli (98.3%), Agromyces tropicus (97.6%), Agromyces ulmi (97.3%), Agromyces flavus (97.2%), and Agromyces italicus (97.0%), whereas the sequence similarity values with respect to the other Agromyces species with validly published names were between 95.3 and 96.7?%. However, the DNA-DNA hybridization values obtained between strain AK-1T and other related strains were well below the threshold that is required for the proposal of a novel species. The DNA G + C content of the strain is 71.8?mol%. The above data in combination with the phenotypic distinctiveness of AK-1T clearly indicate that the strain represents a novel species, for which the name Agromyces arachidis sp. nov. is proposed. The type strain is AK-1T (=MTCC 10524T = JCM 19251T). PMID:24348566

Kaur, Chandandeep; Pinnaka, Anil Kumar; Singh, Nitin Kumar; Bala, Monu

2013-01-01

150

Isolation and Characterization of Strains CVO and FWKO B, Two Novel Nitrate-Reducing, Sulfide-Oxidizing Bacteria Isolated from Oil Field Brine  

PubMed Central

Bacterial strains CVO and FWKO B were isolated from produced brine at the Coleville oil field in Saskatchewan, Canada. Both strains are obligate chemolithotrophs, with hydrogen, formate, and sulfide serving as the only known energy sources for FWKO B, whereas sulfide and elemental sulfur are the only known electron donors for CVO. Neither strain uses thiosulfate as an energy source. Both strains are microaerophiles (1% O2). In addition, CVO grows by denitrification of nitrate or nitrite whereas FWKO B reduces nitrate only to nitrite. Elemental sulfur is the sole product of sulfide oxidation by FWKO B, while CVO produces either elemental sulfur or sulfate, depending on the initial concentration of sulfide. Both strains are capable of growth under strictly autotrophic conditions, but CVO uses acetate as well as CO2 as its sole carbon source. Neither strain reduces sulfate; however, FWKO B reduces sulfur and displays chemolithoautotrophic growth in the presence of elemental sulfur, hydrogen, and CO2. Both strains grow at temperatures between 5 and 40°C. CVO is capable of growth at NaCl concentrations as high as 7%. The present 16s rRNA analysis suggests that both strains are members of the epsilon subdivision of the division Proteobacteria, with CVO most closely related to Thiomicrospira denitrifcans and FWKO B most closely related to members of the genus Arcobacter. The isolation of these two novel chemolithotrophic sulfur bacteria from oil field brine suggests the presence of a subterranean sulfur cycle driven entirely by hydrogen, carbon dioxide, and nitrate. PMID:10831429

Gevertz, Diane; Telang, Anita J.; Voordouw, Gerrit; Jenneman, Gary E.

2000-01-01

151

Isolation and Characterization of Mobile Genetic Elements from Microbial Assemblages Obtained from the Field Research Center Site  

SciTech Connect

Considerable knowledge has been gained from the intensive study of a relatively limited group of bacterial plasmids. Recent efforts have begun to focus on the characterization of, at the molecular level, plasmid populations and associated mobile genetic elements (e.g., transposons, integrons) occurring in a wider range of aquatic and terrestrial habitats. Surprisingly, however, little information is available regarding the incidence and distribution of mobile genetic elements extant in contaminated subsurface environments. Such studies will provide greater knowledge on the ecology of plasmids and their contributions to the genetic plasticity (and adaptation) of naturally occurring subsurface microbial communities. We requested soil cores from the DOE NABIR Field Research Center (FRC) located on the Oak Ridge Reservation. The cores, received in February 2003, were sampled from four areas on the Oak Ridge Site: Area 1, Area 2, Area 3 (representing contaminated subsurface locales) and the background reference sites. The average core length (24 in) was subdivided into three profiles and soil pH and moisture content were determined. Uranium concentration was also determined in bulk samples. Replicate aliquots were fixed for total cell counts and for bacterial isolation. Four different isolation media were used to culture aerobic and facultative microbes from these four study areas. Colony forming units ranged from a minimum of 100 per gram soil to a maximum of 10,000 irrespective of media composition used. The vast majority of cultured subsurface isolates were gram-positive isolates and plasmid characterization was conducted per methods routinely used in the Sobecky laboratory. The percentage of plasmid incidence ranged from 10% to 60% of all isolates tested. This frequency appears to be somewhat higher than the incidence of plasmids we have observed in other habitats and we are increasing the number of isolates screened to confirm this observation. We are also characterizing the plasmid populations at the molecular level. Isolates cultured from the background control site exhibited the lowest occurrence of plasmids (10%). Aliquots of samples were also used in enrichment assays to isolate metal resistant subsurface isolates. Samples were subjected to three different metals (chromium, mercury and cadmium) at two different concentrations and incubated following a conditioning period in which samples were amended with a carbon, nitrogen and phosphorus source. Isolates were plated on metal selection, purified to single isolates and plasmid content determined.

Patricia Sobecky; Cassie Hodges; Kerri Lafferty; Mike Humphreys; Melanie Raimondo; Kristin Tuttle; Tamar Barkay

2004-03-17

152

Symbiotic Characteristics of Rhizobium leguminosarum bv. trifolii Isolates Which Represent Major and Minor Nodule-Occupying Chromosomal Types of Field-Grown Subclover (Trifolium subterraneum L.) †  

PubMed Central

The symbiotic effectiveness and nodulation competitiveness of Rhizobium leguminosarum bv. trifolii soil isolates were evaluated under nonsoil greenhouse conditions. The isolates which we used represented both major and minor nodule-occupying chromosomal types (electrophoretic types [ETs]) recovered from field-grown subclover (Trifolium subterraneum L.). Isolates representing four ETs (ETs 2, 3, 7, and 8) that were highly successful field nodule occupants fixed between 2- and 10-fold less nitrogen and produced lower herbage dry weights and first-harvest herbage protein concentrations than isolates that were minor nodule occupants of field-grown plants. Despite their equivalent levels of abundance in nodules on field-grown subclover plants, ET 2 and 3 isolates exhibited different competitive nodulation potentials under nonsoil greenhouse conditions. ET 3 isolates generally occupied more subclover nodules than isolates belonging to other ETs when the isolates were mixed in 1:1 inoculant ratios and inoculated onto seedlings. In contrast, ET 2 isolates were less successful at nodulating under these conditions. In many cases, ET 2 isolates required a numerical advantage of at least 6:1 to 11:1 to occupy significantly more nodules than their competitors. We identified highly effective isolates that were as competitive as the ET 3 isolates despite representing serotypes that were rarely recovered from nodules of field-grown plants. When one of the suboptimally effective isolates (ET2-1) competed with an effective and competitive isolate (ET31-5) at several different inoculant ratios, the percentages of nodules occupied by the former increased as its numerical advantage increased. Although subclover yields declined as nodule occupancy by ET2-1 increased, surprisingly, this occurred at inoculant ratios at which large percentages of nodules were still occupied by ET31-5. PMID:16349172

Leung, K.; Wanjage, F. N.; Bottomley, P. J.

1994-01-01

153

Arenimonas taoyuanensis sp. nov., a novel bacterium isolated from rice-field soil in China.  

PubMed

A Gram-stain negative, aerobic, rod-shaped bacterial strain, YN2-31A(T), was isolated from rice-field soil, Taoyuan Village, Yunnan province of China. The bacterium was observed to grow at 20-45 °C (optimum 28 °C), at pH 5.0-10.0 (optimum 7.0), and in the presence of 0-2 % (w/v) NaCl (optimum 0-1 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YN2-31A(T) is most closely related to Arenimonas daejeonensis DSM 18060(T) (96.1 %), Arenimonas malthae DSM 21305(T) (95.9 %), Arenimonas donghaensis DSM 18148(T) (95.1 %), Arenimonas composti DSM 18010(T) (94.8 %) and Arenimonas maotaiensis JCM 19710(T) (94.8 %). The major cellular fatty acids (>10 %) were found to be iso-C18:1 ?9c, iso-C15:0, Sum In Feature 3 (C16:1 ?7c/C16:1 ?6c), and C16:0. The major ubiquinone was identified as Q-8 and the major cellular polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and unidentified phospholipids. The genomic DNA G+C content was determined to be 72.3 mol%. The results of the phylogenetic, genetic, phenotypic and chemotaxonomic analyses suggest that strain YN2-31A(T) represents a novel species of the genus Arenimonas, for which the name Arenimonas taoyuanensis sp. nov. is proposed. The type strain is YN2-31A(T) (=DSM 26777(T) = CCTCC AB2012964(T)). PMID:25731739

Zhang, Shi-Ying; Xiao, Wei; Xia, Yun-Sheng; Wang, Yong-Xia; Cui, Xiao-Long; Zhang, Nai-Ming

2015-05-01

154

Antitrypanosomal activity of aloin and its derivatives against Trypanosoma congolense field isolate  

PubMed Central

Background There is an urgent need for the development of new, cheap, safe and highly effective drugs against African trypanosomiasis that affects both man and livestock in sub-Saharan Africa including Ethiopia. In the present study the exudate of Aloe gilbertii, an endemic Aloe species of Ethiopia, aloin, aloe-emodin and rhein were tested for their in vitro and in vivo antitrypanosomal activities against Trypanosoma congolense field isolate. Aloin was prepared from the leaf exudate of A. gilbertii by acid catalyzed hydrolysis. Aloe-emodin was obtained by oxidative hydrolysis of aloin, while rhein was subsequently derived from aloe-emodin by oxidation. In vitro trypanocidal activity tests were conducted on parasites obtained from infected mice, while mice infected with T. congolense were used to evaluate in vivo antitrypanosomal activity of the test substances. Results Results of the study showed that all the test substances arrested parasites motility at effective concentration of 4.0 mg/ml within an incubation period ranging from 15 to 40 min. Moreover, the same concentration of the test substances caused loss of infectivity of the parasites to mice during 30 days observation period. Among the tested substances, rhein showed superior activity with minimum inhibitory concentration (MIC) of 0.4 mg/ml. No adverse reactions were observed when the test substances were administered at a dose of 2000 mg/kg. Rhein at doses of 200 and 400 mg/kg, and the exudate, aloin and aloe-emodin at a dose of 400 mg/kg reduced the level of parasitaemia significantly (P?

2014-01-01

155

Analysis of haemorrhagic septicaemia-causing isolates of Pasteurella multocida by ribotyping and field alternation gel electrophoresis (FAGE).  

PubMed

Ribotyping and field alternation gel electrophoresis (FAGE) were used to examine 19 Pasteurella multocida isolates, and to assess the ability of these techniques to differentiate P. multocida strains that cause haemorrhagic septicaemia (HS). Reproducible patterns were obtained from both methods, with FAGE demonstrating greater discriminatory power than ribotyping. FAGE analysis was particularly useful in distinguishing North American cultures originating from the 1922 Yellowstone National Park Buffalo 'B' strain, demonstrating the ability to detect genetic alterations induced by repeated subculture. A remarkable homogeneity was observed among Asian HS strains following ribotyping and FAGE analysis, with a clear distinction observed between virulent and avirulent HS isolates. This study has illustrated the value of genomic fingerprinting methods in distinguishing strains of similar serotype, and the capability of these methods to produce detailed characterisation of P. multocida isolates. PMID:9444075

Townsend, K M; Dawkins, H J; Papadimitriou, J M

1997-10-16

156

Analysis of Molecular Epidemiology of Chilean Salmonella enterica Serotype Enteritidis Isolates by Pulsed-Field Gel Electrophoresis and Bacteriophage Typing  

PubMed Central

Human Salmonella enterica serotype Enteritidis infections emerged in Chile in 1994. S. enterica serotype Enteritidis phage type 1 isolates predominated in the north, and phage type 4 isolates predominated in the central and southern regions. A study was planned to characterize this epidemic using the best discriminatory typing technique. Research involved 441 S. enterica serotype Enteritidis isolates, including clinical preepidemic samples (n = 74; 1975 to 1993) and epidemic (n = 199), food (n = 72), poultry (n = 57), and some Latin American (n = 39) isolates. The best method was selected based on a sample of preepidemic isolates, analyzing the discriminatory power (DP) obtained by phage typing and randomly amplified polymorphic DNA and pulsed-field gel electophoresis (PFGE) analysis. The highest DP was associated with BlnI PFGE-bacteriophage typing analysis (0.993). A total of 38 BlnI patterns (B patterns) were identified before the epidemic period, 19 since 1994, and only 4 in both periods. Two major clusters were identified by phylogenetic analysis, and the predominant B patterns clustered in the same branch. Combined analysis revealed that specific B pattern-phage type combinations (subtypes) disappeared before 1994, that different genotypes associated with S. enterica serotype Enteritidis phage type 4 had been observed since 1988, and that strain diversity increased before the expansion of S. enterica serotype Enteritidis in 1994. Predominant subtype B3-phage type 4 was associated with the central and southern regions, and subtype B38-phage type 1 was associated with the north (P < 0.0001). Food and poultry isolates matched the predominant S. enterica serotype Enteritidis subtypes, but isolates identified in neighboring countries (Peru and Bolivia) did not match S. enterica serotype Enteritidis subtypes identified in the north of Chile. The results of this work demonstrate that genetic diversity, replacement, and expansion of specific S. enterica serotype Enteritidis subtypes were associated with epidemic changes. PMID:12682153

Fernandez, Jorge; Fica, Alberto; Ebensperger, German; Calfullan, Hector; Prat, Soledad; Fernandez, Alda; Alexandre, Marcela; Heitmann, Ingrid

2003-01-01

157

Diversity of pulsed-field gel electrophoresis patterns of cereulide-producing isolates of Bacillus cereus and Bacillus weihenstephanensis.  

PubMed

Bacillus cereus is an important foodborne pathogen causing diarrhoea, emesis and in, rare cases, lethal poisonings. The emetic syndrome is caused by cereulide, a heat-stable toxin. Originally considered as a rather homogenous group, the emetic strains have since been shown to display some diversity, including the existence of two clusters of mesophilic B. cereus and psychrotolerant B. weihenstephanensis. Using pulsed-field gel electrophoresis (PFGE) analysis, this research aimed to better understand the diversity and spatio-temporal occurrence of emetic strains originating from environmental or food niches vs. those isolated from foodborne cases. The diversity was evaluated using a set of 52 B. cereus and B. weihenstephanensis strains isolated between 2000 and 2011 in ten countries. PFGE analysis could discriminate 17 distinct profiles (pulsotypes). The most striking observations were as follows: (1) more than one emetic pulsotype can be observed in a single outbreak; (2) the number of distinct isolates involved in emetic intoxications is limited, and these potentially clonal strains frequently occurred in successive and independent food poisoning cases; (3) isolates from different countries displayed identical profiles; and (4) the cereulide-producing psychrotolerant B. weihenstephanensis were, so far, only isolated from environmental niches. PMID:24627989

Castiaux, Virginie; N'guessan, Elise; Swiecicka, Izabela; Delbrassinne, Laurence; Dierick, Katelijne; Mahillon, Jacques

2014-04-01

158

Existence of variant strains Fowlpox virus integrated with Reticuloendotheliosis virus in its genome in field isolates in Tanzania.  

PubMed

Fowlpox virus (FPV) is one example of poultry viruses which undergoes recombination with Reticuloendotheliosis virus (REV). Trepidation had been raised, and it was well established on augmented pathogenicity of the FPV upon integration of the full intact REV. In this study, we therefore intended at assessing the integration of REV into FPV genome of the field isolates obtained in samples collected from different regions of Tanzania. DNA extraction of 85 samples (scabs) was performed, and FPV-specific PCR was done by the amplification of the highly conserved P4b gene. Evaluation of FPV-REV recombination was done to FPV-specific PCR positively identified samples by amplifying the env gene and REV long terminal repeats (5' LTR). A 578-bp PCR product was amplified from 43 samples. We are reporting for the first time in Tanzania the existence of variant stains of FPV integrated with REV in its genome as 65 % of FPV identified isolates were having full intact REV integration, 21 % had partial FPV-REV env gene integration and 5 % had partial 5' LTR integration. Despite of the fact that FPV-REV integrated stains prevailed, FPV-REV-free isolates (9 %) also existed. In view of the fact that full intact REV integration is connected with increased pathogenicity of FPV, its existence in the FPV genome of most field isolates could have played a role in increased endemic, sporadic and recurring outbreaks in selected areas in Tanzania. PMID:24557589

Mzula, Alexanda; Masola, Selemani N; Kasanga, Christopher J; Wambura, Philemon N

2014-06-01

159

The use of pulsed-field gel electrophoresis to examine the epidemiology of Bordetella bronchiseptica isolated from cats and other species.  

PubMed Central

A collection (164) of isolates of Bordetella bronchiseptica made predominantly from cats (132) but also from dogs (15), pigs (12) and other species was examined by pulsed field gel electrophoresis following macrorestriction digestion with XbaI. Each isolate was analysed twice and the patterns were entirely reproducible. The isolates fell into 17 different strains (> 3 bands different) and within strains there were numerous subtypes. Feline isolates fell into 12 of the 17 strains. In general, cats housed together had similar or identical strains and subtypes of B. bronchiseptica. There was no difference in the PFGE patterns of isolates made from carrier cats and those from cats with respiratory disease. Isolates from pigs and dogs were in general similar to the feline isolates and there was no great evidence for species specificity. The PFGE pattern of feline and canine isolates were more related to whether the animals were housed together rather than whether they came from dogs or cats. PMID:9593491

Binns, S. H.; Speakman, A. J.; Dawson, S.; Bennett, M.; Gaskell, R. M.; Hart, C. A.

1998-01-01

160

Molecular Typing of Selected Enterococcus faecalis Isolates: Pilot Study Using Multilocus Sequence Typing and Pulsed-Field Gel Electrophoresis  

Microsoft Academic Search

The present study compared the recently developed multilocus sequence typing (MLST) approach with a well-established molecular typing technique, pulsed-field gel electrophoresis (PFGE), for subspecies differen- tiation of Enterococcus faecalis isolates. We sequenced intragenic regions of three E. faecalis antigen-encoding genes (ace, encoding a collagen and laminin adhesin; efaA, encoding an endocarditis antigen; and salA, encoding a cell wall associated antigen)

Sreedhar R. Nallapareddy; Ruay-Wang Duh; Kavindra V. Singh; Barbara E. Murray

2002-01-01

161

Virus excretion and antibody dynamics in goats inoculated with a field isolate of peste des petits ruminants virus.  

PubMed

A field isolate of peste des petits ruminants virus (PPRV) from an outbreak in Tibet, China, was inoculated into goats to investigate the dynamics of virus excretion and antibody production. Further, animals received PPRV vaccine strain Nigeria 75/1. Ocular, nasal and oral samples were tested for the presence of virus antigen by one-step real-time qualitative RT-PCR (qRT-PCR); competitive ELISA (c-ELISA) was used for the measurement of specific antibodies against PPRV. Virus particles could be detected as early as day 3 post-inoculation (pi) and virus excretion lasted for up to day 26 pi. All four goats inoculated with the PPRV field isolate were seropositive as early as day 10 pi. In animals inoculated with the vaccine strain, antibody was detected at day 14 pi, and levels of neutralizing antibodies remained above the protection threshold level (1 : 8) for 8 months. Both virus particles and neutralizing antibodies were detected earlier in goats challenged with the field isolate than in those receiving the vaccine strain. PMID:24589103

Liu, W; Wu, X; Wang, Z; Bao, J; Li, L; Zhao, Y; Li, J

2013-11-01

162

Aquaporin 2 Mutations in Trypanosoma brucei gambiense Field Isolates Correlate with Decreased Susceptibility to Pentamidine and Melarsoprol  

PubMed Central

The predominant mechanism of drug resistance in African trypanosomes is decreased drug uptake due to loss-of-function mutations in the genes for the transporters that mediate drug import. The role of transporters as determinants of drug susceptibility is well documented from laboratory-selected Trypanosoma brucei mutants. But clinical isolates, especially of T. b. gambiense, are less amenable to experimental investigation since they do not readily grow in culture without prior adaptation. Here we analyze a selected panel of 16 T. brucei ssp. field isolates that (i) have been adapted to axenic in vitro cultivation and (ii) mostly stem from treatment-refractory cases. For each isolate, we quantify the sensitivity to melarsoprol, pentamidine, and diminazene, and sequence the genomic loci of the transporter genes TbAT1 and TbAQP2. The former encodes the well-characterized aminopurine permease P2 which transports several trypanocides including melarsoprol, pentamidine, and diminazene. We find that diminazene-resistant field isolates of T. b. brucei and T. b. rhodesiense carry the same set of point mutations in TbAT1 that was previously described from lab mutants. Aquaglyceroporin 2 has only recently been identified as a second transporter involved in melarsoprol/pentamidine cross-resistance. Here we describe two different kinds of TbAQP2 mutations found in T. b. gambiense field isolates: simple loss of TbAQP2, or loss of wild-type TbAQP2 allele combined with the formation of a novel type of TbAQP2/3 chimera. The identified mutant T. b. gambiense are 40- to 50-fold less sensitive to pentamidine and 3- to 5-times less sensitive to melarsoprol than the reference isolates. We thus demonstrate for the first time that rearrangements of the TbAQP2/TbAQP3 locus accompanied by TbAQP2 gene loss also occur in the field, and that the T. b. gambiense carrying such mutations correlate with a significantly reduced susceptibility to pentamidine and melarsoprol. PMID:24130910

Graf, Fabrice E.; Ludin, Philipp; Wenzler, Tanja; Kaiser, Marcel; Brun, Reto; Pyana, Patient Pati; Büscher, Philippe; de Koning, Harry P.; Horn, David; Mäser, Pascal

2013-01-01

163

Flavobacterium aquaticum sp. nov., isolated from a water sample of a rice field.  

PubMed

Strain JC164(T) was isolated from a water sample from a rice field at Jamdih, Mau, Uttar Pradesh, India. Colonies of strain JC164(T) were brown-yellow and cells were Gram-stain-negative. Catalase, oxidase and amylase were present. iso-C(15:0), iso-C(16:0), iso-C15?1 G, iso-C(15:0) 3-OH and iso-C(14:0) were the predominant fatty acids with minor amounts of iso-C(16:0) 3-OH, anteiso-C(15:0), C(16:0), iso-C(16:1) H, iso-C(14:0) 3-OH and iso-C(13:0). Strain JC164(T) contained phosphatidylethanolamine and a few unidentified lipids (L1, L3 and L6) as major polar lipids. Bacteriohopane derivative 1 (BHD1) and diplopterol (DPL) were the major hopanoids. ?-Carotene was one among the several spirilloxanthin series carotenoids present in strain JC164(T). Genomic DNA G+C content was 39.6 mol%. 16S rRNA gene sequence comparisons indicated that strain JC164(T) represents a member of the genus Flavobacterium (family Flavobacteriaceae, class Flavobacteriia). The most closely related taxa to strain JC164(T) were Flavobacterium sasangense YC6274(T) (98.5%), Flavobacterium cucumis R2A45-3(T) (98.1%), Flavobacterium cheniae NJ-26(T) (97.2%) and the novel strain possessed <95.1% sequence similarity with other members of the genus Flavobacterium. However, strain JC164(T) showed 12.5 ± 2, 13.6 ± 1 and 17.4 ± 2% genomic DNA association (based on DNA-DNA hybridization) with Flavobacterium sasangense KCTC 22246(T), Flavobacterium cucumis DSM 18830(T) and Flavobacterium cheniae CGMCC 1.6844(T), respectively. The distinct genomic difference and morphological, physiological and chemotaxonomic differences from the previously described taxa support the classification of strain JC164(T) as a representative of a novel species of the genus Flavobacterium, for which the name Flavobacterium aquaticum sp. nov. is proposed. The type strain is JC164(T) (?=?KCTC 32196(T)?=?CGMCC 1.12398=LMG 27251(T)). PMID:23543500

Subhash, Y; Sasikala, Ch; Ramana, Ch V

2013-09-01

164

Methanocella conradii sp. nov., a Thermophilic, Obligate Hydrogenotrophic Methanogen, Isolated from Chinese Rice Field Soil  

PubMed Central

Background Methanocellales contributes significantly to anthropogenic methane emissions that cause global warming, but few pure cultures for Methanocellales are available to permit subsequent laboratory studies (physiology, biochemistry, etc.). Methodology/Principal Findings By combining anaerobic culture and molecular techniques, a novel thermophilic methanogen, strain HZ254T was isolated from a Chinese rice field soil located in Hangzhou, China. The phylogenetic analyses of both the 16S rRNA gene and mcrA gene (encoding the ? subunit of methyl-coenzyme M reductase) confirmed its affiliation with Methanocellales, and Methanocella paludicola SANAET was the most closely related species. Cells were non-motile rods, albeit with a flagellum, 1.4–2.8 µm long and by 0.2–0.3 µm in width. They grew at 37–60°C (optimally at 55°C) and salinity of 0–5 g NaCl l?1 (optimally at 0–1 g NaCl l?1). The pH range for growth was 6.4–7.2 (optimum 6.8). Under the optimum growth condition, the doubling time was 6.5–7.8 h, which is the shortest ever observed in Methanocellales. Strain HZ254T utilized H2/CO2 but not formate for growth and methane production. The DNA G+C content of this organism was 52.7 mol%. The sequence identities of 16S rRNA gene and mcrA gene between strain HZ254T and SANAET were 95.0 and 87.5% respectively, and the genome based Average Nucleotide Identity value between them was 74.8%. These two strains differed in phenotypic features with regard to substrate utilization, possession of a flagellum, doubling time (under optimal conditions), NaCl and temperature ranges. Taking account of the phenotypic and phylogenetic characteristics, we propose strain HZ254T as a representative of a novel species, Methanocella conradii sp. nov. The type strain is HZ254T (?=?CGMCC 1.5162T?=?JCM 17849T?=?DSM 24694T). Conclusions/Significance Strain HZ254T could potentially serve as an excellent laboratory model for studying Methanocellales due to its fast growth and consistent cultivability. PMID:22530002

Lü, Zhe; Lu, Yahai

2012-01-01

165

Dyella kyungheensis sp. nov., isolated from soil of a cornus fruit field.  

PubMed

A Gram-reaction-negative, aerobic, motile by one polar flagellum, yellow-pigmented, rod-shaped bacterium, designated strain THG-B117(T), was isolated from soil of a cornus fruit field of Hoengseong province in South Korea and its taxonomic position was investigated by a polyphasic study. Strain THG-B117(T) grew well at 25-30 °C and at pH 6.0-8.0 in the absence of NaCl on nutrient agar. On the basis of 16S rRNA gene sequence similarity, strain THG-B117(T) was shown to belong to the family Xanthomonadaceae and be related to Dyella japonica XD53(T) (98.7?% similarity), Dyella terrae JS14-6(T) (98.0?%), Dyella koreensis BB4(T) (96.9?%), Dyella soli JS12-10(T) (96.9?%) and Dyella thiooxydans ATSB10(T) (96.7?%). DNA-DNA hybridization experiments showed that DNA relatedness between strain THG-B117(T) and its phylogenetically closest neighbours was below 45.1?%. The G+C content of the genomic DNA of strain THG-B117(T) was 64.8 mol%. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, unidentified aminolipids, unidentified aminophospholipids and unidentified phospholipids. Phenotypic and chemotaxonomic data (major ubiquinone was Q-8, and major fatty acids were iso-C15?:?0, iso-C16?:?0, iso-C17?:?0 and iso-C17?:?1?9c) supported the affiliation of strain THG-B117(T) with the genus Dyella. The results of physiological and biochemical tests suggested that strain THG-B117(T) was different genotypically and phenotypically from recognized species of the genus Dyella, and represents a novel species of this genus. The name Dyella kyungheensis sp. nov. is proposed, with the type strain THG-B117(T) (?=?KACC 16981(T)?=?JCM 18747(T)). PMID:23667147

Son, Heung-Min; Yang, Jung-Eun; Yi, Eun-Ji; Park, YongJin; Won, Kyung-Hwa; Kim, Ju-Han; Han, Chang-Kyun; Kook, MooChang; Yi, Tae-Hoo

2013-10-01

166

Brachybacterium ginsengisoli sp. nov., isolated from soil of a ginseng field.  

PubMed

A novel Gram-staining-positive, aerobic bacterium, designed DCY80(T), was isolated from soil of a ginseng field in the Republic of Korea. 16S rRNA gene sequence analysis revealed that strain DCY80(T) belonged to the genus Brachybacterium (95.8-98.2?% similarity) and was most closely related to Brachybacterium faecium DSM 4810(T) (98.2?%). Colonies were circular, entire, low-convex, opaque and 0.5-1.0 mm in diameter after growth for 2 days on TSA at 30 °C. Growth occurred at 4-34 °C (optimum, 25 °C), at pH 5.0-10.0 (optimum, pH 6.5-7.0) and in the presence of 0-7.0?% NaCl. Strain DCY80(T) produced siderophores and was sensitive to penicillin G, erythromycin, cefazolin, oleandomycin, ceftazidime, vancomycin, tetracycline, novobiocin, carbamicillin, rifampicin and neomycin. The DNA G+C content was 71.0 mol%. Levels of DNA-DNA relatedness between strain DCY80(T) and B. faecium DSM 4810(T), B. paraconglomeratum KCTC 9916(T), B. saurashtrense DSM 23186(T) and B. conglomeratum KCTC 9915(T) were 46.9±0.5, 28.9±0.6, 20.4±0.9 and 17.3±0.4?%, respectively. The cell-wall peptidoglycan of strain DCY80(T) contained meso-diaminopimelic acid as the diagnostic diamino acid. The menaquinones were MK-7 (85.8?%) and MK-8 (14.2?%). The major cellular fatty acids were anteiso-C15?:?0 (69.1?%) and anteiso-C17?:?0 (12.2?%). Phosphatidylglycerol, diphosphatidylglycerol, an unidentified glycolipid, two unidentified phospholipids and five unidentified polar lipids were found. On the basis of our phenotypic and genotypic analyses, strain DCY80(T) represents a novel species of the genus Brachybacterium, for which the name Brachybacterium ginsengisoli sp. nov. is proposed (type strain DCY80(T)?=?KCTC 29226(T)?=?JCM 19356(T)). PMID:24944333

Hoang, Van-An; Kim, Yeon-Ju; Nguyen, Ngoc-Lan; Yang, Deok-Chun

2014-09-01

167

Phylogenetic characterization of bovine parainfluenza 3 from contaminated cell cultures and field isolates from Brazil  

PubMed Central

Genomic fragments of the HN and L genes from Brazilian bovine parainfluenza 3 virus (bPIV-3) isolated as contaminants from cell cultures and clinical specimens were amplified by reverse transcription-polymerase chain reaction (RT-PCR), sequenced using specific degenerate primers and analyzed by phylogenetic comparison with reference strains of bPI3V. The Brazilian isolates revealed a high degree of genomic when compared to SF4/32 prototype strain, within the recently proposed genotype A of bPIV-3. PMID:24031776

de Almeida Vaucher, Rodrigo; Dezen, Diogenes; Simonetti, Amauri Braga; Spilki, Fernando Rosado; Roehe, Paulo Michel

2011-01-01

168

Genetic diversity of Mycoplasma gallisepticum field isolates using partial sequencing of the pvpA gene fragment in Russia.  

PubMed

The genetic diversity of the pvpA gene of Mycoplasma gallisepticum (MG) samples originating from commercial chickens was investigated. In the present study, we evaluated the genetic variability of 26 field samples of MG detected in commercial chickens and turkeys from 18 regions of Russia and compared them to the reference strains of MG available in GenBank. Genetic variability was evaluated by partial nucleotide sequencing of the pvpA gene, which encodes a putative cytadhesin protein. Comparisons with MG strains and isolates from the United States, Australia, China, and Iran using sequence analysis of PCR products showed that Russian MG field samples clustered more closely to each other than to the international reference MG strains. The MG pvpA sequences were found to be highly variable with a discrimination index of 0.975 for Russian field samples. No apparent cluster was found using the criteria of year or location of detection. DNA sequence polymorphism and size variation in the pvpA gene were shown among the Russian MG field samples and could be used for MG typing. These findings might help better understand the relationship among MG isolates from Russia and other countries. PMID:20608536

Sprygin, A V; Andreychuk, D B; Elatkin, N P; Zinyakov, N G; Kolosov, S N; Mudrak, N S; Irza, V N; Drygin, V V; Borisov, A V; Perevozchikova, N A

2010-06-01

169

Isolation and identification of atrazine-degrading bacteria from corn field soil in Fars province of Iran.  

PubMed

In this study several agricultural fields with a long history of atrazine application in Fars province of Iran have been explored for their potential of atrazine biodegradation. After several subculturing for a period of 300 days acclimation, leads to an enhancement of atrazine biodegradation rate. A successful enrichment culture with a high capability for atrazine degradation was obtained (88%). A combination of enrichment culture technique, in a basal salt medium containing atrazine and carbon sources under nitrogen limitation and plating on indicator atrazine agar, have permitted the isolation of bacterial consortium with high capability of using atrazine as a nitrogen source. Seven gram-negative and one gram-positive bacterial strain, which were able to use this herbicide as a sole source of nitrogen, were isolated from Darehasalouie Kavar corn field soil. Based on physiological, biochemical and nutritional characteristics, the isolated bacteria were identified as Pseudomonas alcaligenes, Acidovorax sp., Pseudomonas putida, Ralstonia eutrophus, Pseudomonas syiringe, Erwinia tracheiphila, Entrobacter agglomerans and Micrococcus varians. Therefore, the bacterial consortium in liquid culture containing carbon sources and atrazine as a sole source of nitrogen, degrade added atrazine more than 80%. PMID:19069990

Dehghani, M; Nasseri, S; Amin, S; Naddafee, K; Taghavi, M; Yunesian, M; Maleky, N

2007-01-01

170

Device Isolation in Hybrid Field-Effect Transistors by Semiconductor Micropatterning Using Picosecond Lasers  

E-print Network

. First, zinc oxide (ZnO) is deposited onto Si=SiO2 substrates by sol-gel methods and used to create n-channel FETs with aluminum top electrodes. Isolation of individual FETs enables the clear observation-matrix displays, and transparent or flexible micro- electronics [1­13]. However, leakage currents and bias effects

Evans, Paul G.

171

Genome of Rhizobium sp. UR51a, Isolated from Rice Cropped in Southern Brazilian Fields  

PubMed Central

Rhizobium sp. UR51a is a Gram-negative bacterium isolated from roots of rice plants, and it presents plant growth-promoting abilities. The nutrient uptake in rice plants inoculated with UR51a was satisfactory. The genome of strain UR51a is composed of 5,233,443-bp and harbors 5,079 coding sequences. PMID:25838497

de Souza, Rocheli; Sant’Anna, Fernando Hayashi; Ambrosini, Adriana; Tadra-Sfeir, Michele; Faoro, Helisson; Pedrosa, Fabio Oliveira; Souza, Emanuel Maltempi

2015-01-01

172

Plasmodium falciparum field isolates from areas of repeated emergence of drug resistant malaria show no evidence of hypermutator phenotype.  

PubMed

Multiple transcontinental waves of drug resistance in Plasmodium falciparum have originated in Southeast Asia before spreading westward, first into the rest of Asia and then to sub-Saharan Africa. In vitro studies have suggested that hypermutator P. falciparum parasites may exist in Southeast Asia and that an increased rate of acquisition of new mutations in these parasites may explain the repeated emergence of drug resistance in Southeast Asia. This study is the first to test the hypermutator hypothesis using field isolates. Using genome-wide SNP data from human P. falciparum infections in Southeast Asia and West Africa and a test for relative rate differences we found no evidence of increased relative substitution rates in P. falciparum isolates from Southeast Asia. Instead, we found significantly increased substitution rates in Mali and Bangladesh populations relative to those in populations from Southeast Asia. Additionally we found no association between increased relative substitution rates and parasite clearance following treatment with artemisinin derivatives. PMID:25514047

Brown, Tyler S; Jacob, Christopher G; Silva, Joana C; Takala-Harrison, Shannon; Djimdé, Abdoulaye; Dondorp, Arjen M; Fukuda, Mark; Noedl, Harald; Nyunt, Myaing Myaing; Kyaw, Myat Phone; Mayxay, Mayfong; Hien, Tran Tinh; Plowe, Christopher V; Cummings, Michael P

2015-03-01

173

Generation of isolated sub-20-attosecond pulses from He atoms by two-color midinfrared laser fields  

NASA Astrophysics Data System (ADS)

We propose an efficient method for the generation of ultrabroadband supercontinuum spectra and isolated ultrashort attosecond laser pulses from He atoms with two-color midinfrared laser fields. High-order harmonic generation (HHG) is obtained by solving the time-dependent Schrödinger equation accurately by means of the time-dependent generalized pseudospectral method. We found that the optimizing two-color midinfrared laser pulse allows the HHG cutoff to be significantly extended, leading to the production of an ultrabroadband supercontinuum. As a result, an isolated 18-attosecond pulse can be generated directly by the superposition of the supercontinuum harmonics. To facilitate the exploration of the ultrashort attosecond generation mechanisms, we perform both a semiclassical simulation and a wavelet time-frequency transform.

Li, Peng-Cheng; Laughlin, Cecil; Chu, Shih-I.

2014-02-01

174

Population Synthesis of Young Isolated Neutron Stars: The Effect of Fallback Disk Accretion and Magnetic Field Evolution  

NASA Astrophysics Data System (ADS)

The spin evolution of isolated neutron stars (NSs) is dominated by their magnetic fields. The measured braking indices of young NSs show that the spin-down mechanism due to magnetic dipole radiation with constant magnetic fields is inadequate. Assuming that the NS magnetic field is buried by supernova fallback matter and re-emerges after accretion stops, we carry out a Monte Carlo simulation of the evolution of young NSs, and show that most of the pulsars have braking indices ranging from -1 to 3. The results are compatible with the observational data of NSs associated with supernova remnants. They also suggest that the initial spin periods of NSs might occupy a relatively wide range.

Fu, Lei; Li, Xiang-Dong

2013-10-01

175

POPULATION SYNTHESIS OF YOUNG ISOLATED NEUTRON STARS: THE EFFECT OF FALLBACK DISK ACCRETION AND MAGNETIC FIELD EVOLUTION  

SciTech Connect

The spin evolution of isolated neutron stars (NSs) is dominated by their magnetic fields. The measured braking indices of young NSs show that the spin-down mechanism due to magnetic dipole radiation with constant magnetic fields is inadequate. Assuming that the NS magnetic field is buried by supernova fallback matter and re-emerges after accretion stops, we carry out a Monte Carlo simulation of the evolution of young NSs, and show that most of the pulsars have braking indices ranging from –1 to 3. The results are compatible with the observational data of NSs associated with supernova remnants. They also suggest that the initial spin periods of NSs might occupy a relatively wide range.

Fu, Lei; Li, Xiang-Dong, E-mail: lixd@nju.edu.cn [Department of Astronomy, Nanjing University, Nanjing 210093 (China)

2013-10-01

176

A multiplex RT-PCR assay for rapid and differential diagnosis of four porcine diarrhea associated viruses in field samples from pig farms in East China from 2010 to 2012.  

PubMed

Since October 2010, clinical outbreaks of diarrhea in suckling piglets have reemerged in pig-producing areas of China, causing an acute increase in the morbidity and mortality in young piglets. Four viruses, porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), porcine group A rotaviruses (GAR), and porcine circovirus 2 (PCV2), are the major causative agents of enteric disease in piglets. A novel multiplex reverse transcription-polymerase chain reaction (mRT-PCR) was developed for simultaneous detection of the four viruses in field samples from piglets. A mixture of four previously published pairs of primers were used for amplification of viral gene, yielding four different amplicons with sizes of 481 bp for PCV2, 651 bp for PEDV, 859 bp for TGEV, and 309 bp for GAR, respectively. The sensitivity of the mRT-PCR using plasmids containing the specific viral target fragments was 2.17 × 10(3), 2.1 × 10(3), 1.74 × 10(4) and 1.26 × 10(4)copies for the four viruses, respectively. A total of 378 field samples were collected from suckling piglets with diarrhea in East China from October 2010 to December 2012, and detected by mRT-PCR. The PEDV-positive rates of the three years were 69.2%, 62.8% and 54.9%, respectively, suggesting that PEDV was a major pathogen in these diarrheal outbreaks. Taken together, all data indicated that this mRT-PCR assay was a simple, rapid, sensitive, and cost-effective detection method for clinical diagnosis of mixed infections of porcine diarrhea associated viruses. PMID:23988656

Zhao, Jin; Shi, Bao-jun; Huang, Xiao-guo; Peng, Ming-yi; Zhang, Xiao-min; He, Dan-ni; Pang, Ran; Zhou, Bin; Chen, Pu-yan

2013-12-01

177

Identification of a novel equine infectious anemia virus field strain isolated from feral horses in southern Japan.  

PubMed

Although equine infectious anemia (EIA) was described more than 150 years ago, complete genomic sequences have only been obtained from two field strains of EIA virus (EIAV), EIAV(Wyoming) and EIAV(Liaoning). In 2011, EIA was detected within the distinctive feral Misaki horse population that inhabits the Toi-Cape area of southern Japan. Complete proviral sequences comprising a novel field strain were amplified directly from peripheral blood of one of these EIAV-infected horses and characterized by nucleotide sequencing. The complete provirus of Miyazaki2011-A strain is 8208 bp in length with an overall genomic organization typical of EIAV. However, this field isolate possesses just 77.2 and 78.7?% nucleotide sequence identity with the EIAV(Wyoming) and EIAV(Liaoning) strains, respectively, while similarity plot analysis suggested all three strains arose independently. Furthermore, phylogenetic studies using sequences obtained from all EIAV-infected Misaki horses against known viral strains strongly suggests these Japanese isolates comprise a separate monophyletic group. PMID:23100364

Dong, Jian-Bao; Zhu, Wei; Cook, Frank R; Goto, Yoshitaka; Horii, Yoichiro; Haga, Takeshi

2013-02-01

178

Extent of high-affinity iron transport systems in field isolates of rhizobia  

Microsoft Academic Search

A Uruguayan rhizobia collection (67 isolates) obtained from nodules of Medicago sativa, Melilotus albus, Medicago polymorpha, Trifolium subterraneum, Trifolium repens, Trifolium vesiculosum, Lotus\\u000a corniculatus, Lotus subbiflorus, Lotus pedunculatus, Ornithopus sp. and Adesmia sp. has been examined to assess the occurrence of high affinity iron uptake systems.\\u000a \\u000a CAS (Chrome-azurol S)-assay results suggested that most of the free-living form of these microsymbionts

E. Fabiano; G. Gualtieri; C. Pritsch; G. Polla; A. Arias

1994-01-01

179

MAGNETIC FIELD IN THE ISOLATED MASSIVE DENSE CLUMP IRAS 20126+4104  

SciTech Connect

We measured polarized dust emission at 350 {mu}m toward the high-mass star-forming massive dense clump IRAS 20126+4104 using the SHARC II Polarimeter, SHARP, at the Caltech Submillimeter Observatory. Most of the observed magnetic field vectors agree well with magnetic field vectors obtained from a numerical simulation for the case when the global magnetic field lines are inclined with respect to the rotation axis of the dense clump. The results of the numerical simulation show that rotation plays an important role on the evolution of the massive dense clump and its magnetic field. The direction of the cold CO 1-0 bipolar outflow is parallel to the observed magnetic field within the dense clump as well as the global magnetic field, as inferred from optical polarimetry data, indicating that the magnetic field also plays a critical role in an early stage of massive star formation. The large-scale Keplerian disk of the massive (proto)star rotates in an almost opposite sense to the clump's envelope. The observed magnetic field morphology and the counterrotating feature of the massive dense clump system provide hints to constrain the role of magnetic fields in the process of high-mass star formation.

Shinnaga, Hiroko; Phillips, Thomas G. [California Institute of Technology Submillimeter Observatory, 111 Nowelo Street, Hilo, HI 96720 (United States); Novak, Giles [Department of Physics and Astronomy, Northwestern University, 633 Clark Street Evanston, IL 60208 (United States); Vaillancourt, John E. [Stratospheric Observatory for Infrared Astronomy, Universities Space Research Association, NASA Ames Research Center, Moffet Field, CA 94035 (United States); Machida, Masahiro N. [Department of Earth and Planetary Sciences, Faculty of Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Kataoka, Akimasa [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Tomisaka, Kohji [National Astronomical Observatory of Japan and Department of Astronomy, School of Physical Sciences, Graduate University for Advanced Studies (SOKENDAI), Osawa 2-21-1, Mitaka, Tokyo 181-8588 (Japan); Davidson, Jacqueline; Houde, Martin [School of Physics, University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Perth (Australia); Dowell, C. Darren [Jet Propulsion Laboratory, California Institute of Technology, MS 169-506, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Leeuw, Lerothodi [SETI Institute, 515 North Whisman Avenue, Mountain View, CA 94043 (United States)

2012-05-10

180

Use of an internal control in a quantitative RT-PCR assay for quantitation of porcine epidemic diarrhea virus shedding in pigs  

Microsoft Academic Search

Porcine epidemic diarrhea virus (PEDV), a member of the family Coronaviridae, has caused a devastating enteric disease in the Korean swine industry. Previously, the differences between virulent field PEDV strains and a Vero cell culture adapted PEDV DR13 strain were determined using restriction fragment length polymorphism analysis (RFLP), and PEDV shedding patterns in pigs were reported. In an extension to

Dae-Sub Song; Bo-Kyu Kang; Sang-Sun Lee; Jeong-Sun Yang; Hyoung-Joon Moon; Jin-Sik Oh; Gun-Woo Ha; Yong-Suk Jang; Bong-Kyun Park

2006-01-01

181

Manipulation of the recombination channels and isolated attosecond pulse generation from HeH2+ with multicycle combined field  

NASA Astrophysics Data System (ADS)

We present a method to manipulate the recombination channels in harmonic emission from HeH2+ via combing a multicycle trapezoidal laser field and a static electric field. By solving the time-dependent Schrödinger equation, we find that the positive peak intensity can steer the electron localization by controlling the electron transfer at the time of laser polarization direction antiparallel to the permanent dipole of HeH2+. With appropriate laser parameters, the recombination channels originating from the nucleus He2+ are effectively controlled by enhancing electron localization around the nucleus H+. Additionally, an isolated 48-as pulse can be obtained by superposing proper harmonics. Time-frequency maps, electronic wave packet probability density and a laser dressed picture of the Coulomb potential are adopted to provide the underlying physical mechanism.

Miao, Xiang-Yang; Zhang, Cai-Ping

2014-11-01

182

An efficient thermotolerant and halophilic biosurfactant-producing bacterium isolated from Dagang oil field for MEOR application  

NASA Astrophysics Data System (ADS)

Dagang Oil field (Petro China Company Limited) is one of the most productive oil fields in China. In this study, 34 biosurfactant-producing strains were isolated and cultured from petroleum reservoir of Dagang oil field, using haemolytic assay and the qualitative oil-displacement test. On the basis of 16S rDNA analysis, the isolates were closely related to the species in genus Pseudomonas, Staphylococcus and Bacillus. One of the isolates identified as Bacillus subtilis BS2 were selected for further study. This bacterium was able to produce a type of biosurfactant with excessive foam-forming properties at 37ºC as well as at higher temperature of 55ºC. The biosurfactant produced by the strain BS2 could reduce the surface tension of the culture broth from 70.87 mN/m to 28.97 mN/m after 8 days of incubation at 37ºC and to 36.15 mN/m after 20 days of incubation at 55ºC, respectively. The biosurfactant showed stability at high temperature (up to 120ºC), a wide range of pH (2 to 12) and salt concentrations (up to 12%) offering potential for biotechnology. Fourier transform infrared (FT-IR) spectrum of extracted biosurfactant tentatively characterized the produced biosurfactant as glycolipid derivative. Elemental analysis of the biosurfactant by energy dispersive X-ray spectroscopy (EDS) reveals that the biosurfactant was anionic in nature. 15 days of biodegradation of crude oil suggested a preferential usage of n-alkane upon microbial metabolism of BS2 as a carbon substrate and consequently also for the synthesis of biosurfactants. Core flood studies for oil release indicated 9.6% of additional oil recovery over water flooding at 37ºC and 7.2% of additional oil recovery at 55 ºC. Strain BS2 was characterized as an efficient biosurfactant-producing, thermotolerant and halophillic bacterium and has the potential for application for microbial enhanced oil recovery (MEOR) through water flooding in China's oil fields even in situ as adapted to reservoir chemistry and temperature.

Wu, Langping; Richnow, Hans; Yao, Jun; Jain, Anil

2014-05-01

183

In vitro inhibition of field isolates of feline calicivirus with short interfering RNAs (siRNAs).  

PubMed

Feline calicivirus (FCV) is a common infection of domestic cats. Most infections are mild and self-limiting; however more severe disease manifestations, such as FCV-associated virulent systemic disease, may be associated with significant morbidity and mortality. There is currently a lack of effective antiviral treatments for these disease manifestations. In this study, a panel of eight siRNAs were designed to target four conserved regions of the FCV genome. siRNAs were screened for in vitro antiviral efficacy against the reference strain FCV F9 by determination of extracellular virus titres and morphological assessment of protection from cytopathic effect. Three of the siRNA (FCV3.7, FCV4.1, and FCV4.2) demonstrated a marked antiviral effect with a greater than 99% reduction in extracellular viral titre. Titration of these effective siRNAs demonstrated a clear concentration-response relationship, with IC50 values of approximately 1nM, and combination treatment with multiple siRNAs demonstrated additive or synergistic effects. To assess the potential usefulness of the compounds in a clinical setting, siRNAs were screened against a panel of six recent Australian FCV isolates from cats with FCV-related disease. The siRNAs shown to be effective against the reference strain FCV F9 were active against the majority of the isolates tested, although some variability was noted. Taken together these data suggest potential therapeutic application of antiviral RNAi for treating FCV-associated disease in cats. PMID:25770890

McDonagh, Phillip; Sheehy, Paul A; Fawcett, Anne; Norris, Jacqueline M

2015-05-15

184

High-resolution melt PCR analysis for rapid identification of Chlamydia abortus live vaccine strain 1B among C. abortus strains and field isolates.  

PubMed

We describe a novel high-resolution melt assay that clearly differentiates Chlamydia abortus live vaccine strain 1B from field C. abortus strains and field wild-type isolates based on previously described single nucleotide polymorphisms. This modern genotyping technique is inexpensive, easy to use, and less time-consuming than PCR-RFLP. PMID:22652433

Vorimore, Fabien; Cavanna, Noémie; Vicari, Nadia; Magnino, Simone; Willems, Hermann; Rodolakis, Annie; Siarkou, Victoria I; Laroucau, Karine

2012-09-01

185

7 CFR 201.76 - Minimum Land, Isolation, Field, and Seed Standards.  

Code of Federal Regulations, 2014 CFR

...distance from contaminant Feet Meters Pollen (parent border) Feet Meters 330 100...strip a minimum of one foot (0.31m) in width...certified from fields with problems listed above: ...contains not more than 15 percent sterile plants may...

2014-01-01

186

7 CFR 201.76 - Minimum Land, Isolation, Field, and Seed Standards.  

Code of Federal Regulations, 2011 CFR

...distance from contaminant Feet Meters Pollen (parent border) Feet Meters 330 100...strip a minimum of one foot (0.31m) in width...certified from fields with problems listed above: ...contains not more than 15 percent sterile plants may...

2011-01-01

187

7 CFR 201.76 - Minimum Land, Isolation, Field, and Seed Standards.  

Code of Federal Regulations, 2010 CFR

...distance from contaminant Feet Meters Pollen (parent border) Feet Meters 330 100...strip a minimum of one foot (0.31m) in width...certified from fields with problems listed above: ...contains not more than 15 percent sterile plants may...

2010-01-01

188

7 CFR 201.76 - Minimum Land, Isolation, Field, and Seed Standards.  

Code of Federal Regulations, 2013 CFR

...distance from contaminant Feet Meters Pollen (parent border) Feet Meters 330 100...strip a minimum of one foot (0.31m) in width...certified from fields with problems listed above: ...contains not more than 15 percent sterile plants may...

2013-01-01

189

7 CFR 201.76 - Minimum Land, Isolation, Field, and Seed Standards.  

Code of Federal Regulations, 2012 CFR

...distance from contaminant Feet Meters Pollen (parent border) Feet Meters 330 100...strip a minimum of one foot (0.31m) in width...certified from fields with problems listed above: ...contains not more than 15 percent sterile plants may...

2012-01-01

190

Characterisation of E. coli O157 isolates from bovine hide and beef trimming in Irish abattoirs by pulsed field gel electrophoresis.  

PubMed

Escherichia coli O157 isolates from bovine hide (n=117) and beef trimmings (n=32) from a single abattoir were examined by pulsed field gel electrophoresis (PFGE). Using BioNumerics software, dendrograms of isolates from each sample type (i.e. hide and beef trimming) were produced. In assessing the genetic relatedness of isolates, a similarity criterion of 80% was applied. The 117 E. coli O157 hide isolates were grouped into 14 clusters, comprising of 109 different PFGE profiles. Of the 109 different PFGE profiles, 8 were common to multiple isolates (i.e. shared 100% similarity by PFGE). The 32 E. coli O157 beef trimming isolates produced 28 different PFGE profiles and 2 clusters. Of the 28 PFGE profiles, 2 were common to multiple isolates and the remaining 26 were distinct. On a number of sampling occasions, isolates displaying identical PFGE patterns were recovered from multiple isolates collected from a single sample type (i.e. hides or trimmings), suggesting cross contamination from contaminated hides/animals to uncontaminated hides/animals and from contaminated beef trimmings to uncontaminated beef trimmings during abattoir operations. PMID:15649539

Duffy, G; O'Brien, S B; Carney, E; Sheridan, J J; McDowell, D A; Blair, I S

2005-03-01

191

Paenibacillus ginsengihumi sp. nov., a bacterium isolated from soil in a ginseng field.  

PubMed

Strain DCY16T, a Gram-positive, spore-forming, rod-shaped, motile bacterium, was isolated from soil and characterized in order to determine its taxonomic position. 16S rRNA gene sequence analysis revealed that strain DCY16T belonged to the genus Paenibacillus; highest sequence similarities were with Paenibacillus validus JCM 9077T (94.4 %), P. chinjuensis WN9T (94.4 %), P. naphthalenovorans DSM 14203T (94.2 %), P. ehimensis KCTC 3748T (92.8 %) and P. elgii KCTC 10016BP(T) (92.4 %). Chemotaxonomic data revealed that strain DCY16T possessed menaquinone MK-7 and the predominant fatty acids were C15 : 0 anteiso, C17 : 0 anteiso, C16 : 0 and C16 : 0 iso. The DNA G+C content of strain DCY16T was 50.9 mol%. Results of physiological and biochemical tests clearly demonstrated that strain DCY16T represents a distinct Paenibacillus species. Based on these data, DCY16T (=KCTC 13141T =JCM 14928T) should be classified as the type strain of a novel species, for which the name Paenibacillus ginsengihumi sp. nov. is proposed. PMID:18450707

Kim, Myung Kyum; Kim, Young-Ae; Park, Min-Ju; Yang, Deok-Chun

2008-05-01

192

Discovery of a candidate old, isolated neutron star in the field of a galactic cirrus cloud  

NASA Technical Reports Server (NTRS)

New x-ray optical, and radio observations of the bright, unidentified x-ray source MS 0317.7-6647 are presented suggesting that this source is a likely compact stellar remnant. As part of the Einstein Extended Medium Sensivity Survey, this source was discovered serendipitously in the Einstein Imaging Proportional Counter pointing towards the nearby (4.5 Mpc) spiral galaxy NGC 1313. The very high x-ray to optical flux ratio, pointlike ROSAT HRI detection, and extremely soft component in the x-ray spectrum of MS 0317.7-6647 eliminate all the usual classes of optical counterparts to faint x-ray sources except for a very massive x-ray binary (and black hole candidate) in NGC 1313, a nearby, companionless pulsar similar to Geminga, or a very nearby ( approximately 100 pc) isolated, old neutron star slowly accreting interstellar matter onto its magnetic poles. The presence of an IR cirrus cloud which shadows the approximately 0.25 keV x-ray background in this direction supports the latter possibilty.

Stocke, John T.; Wang, Q. Daniel; Perlman, Eric S.; Donahue, Megan E.; Schachter, Jonathan F.

1995-01-01

193

Phylogenetic Diversity of Aerobic Saprotrophic Bacteria Isolated from the Daqing Oil Field  

Microsoft Academic Search

A diverse and active microbial community in the stratal waters of the Daqing oil field (China), which is exploited with the use of water-flooding, was found to contain aerobic chemoheterotrophic bacteria (including hydrocarbon-oxidizing ones) and anaerobic fermentative, sulfate-reducing, and methanogenic bacteria. The aerobic bacteria were most abundant in the near-bottom zones of injection wells. Twenty pure cultures of aerobic saprotrophic

T. N. Nazina; A. A. Grigor'yan; Yan-Fen Xue; D. Sh. Sokolova; E. V. Novikova; T. P. Tourova; A. B. Poltaraus; S. S. Belyaev; M. V. Ivanov

2002-01-01

194

Validation of the Abbreviated Brucella AMOS PCR as a Rapid Screening Method for Differentiation of Brucella abortus Field Strain Isolates and the Vaccine Strains, 19 and RB51  

PubMed Central

The Brucella AMOS PCR assay was previously developed to identify and differentiate specific Brucella species. In this study, an abbreviated Brucella AMOS PCR test was evaluated to determine its accuracy in differentiating Brucella abortus into three categories: field strains, vaccine strain 19 (S19), and vaccine strain RB51/parent strain 2308 (S2308). Two hundred thirty-one isolates were identified and tested by the conventional biochemical tests and Brucella AMOS PCR. This included 120 isolates identified as B. abortus S19, 9 identified as B. abortus strain RB51, 57 identified as B. abortus biovar 1, 15 identified as B. abortus bv. 2, 1 identified as B. abortus bv. 2 (M antigen dominant), 7 identified as B. abortus bv. 4, and 22 identified as B. abortus S2308 and isolated from experimentally infected cattle. The Brucella AMOS PCR correctly identified each isolate as RB51/S2308, S19, or a field strain of Brucella. PMID:10921983

Ewalt, Darla R.; Bricker, Betsy J.

2000-01-01

195

Validation of the abbreviated Brucella AMOS PCR as a rapid screening method for differentiation of Brucella abortus field strain isolates and the vaccine strains, 19 and RB51.  

PubMed

The Brucella AMOS PCR assay was previously developed to identify and differentiate specific Brucella species. In this study, an abbreviated Brucella AMOS PCR test was evaluated to determine its accuracy in differentiating Brucella abortus into three categories: field strains, vaccine strain 19 (S19), and vaccine strain RB51/parent strain 2308 (S2308). Two hundred thirty-one isolates were identified and tested by the conventional biochemical tests and Brucella AMOS PCR. This included 120 isolates identified as B. abortus S19, 9 identified as B. abortus strain RB51, 57 identified as B. abortus biovar 1, 15 identified as B. abortus bv. 2, 1 identified as B. abortus bv. 2 (M antigen dominant), 7 identified as B. abortus bv. 4, and 22 identified as B. abortus S2308 and isolated from experimentally infected cattle. The Brucella AMOS PCR correctly identified each isolate as RB51/S2308, S19, or a field strain of Brucella. PMID:10921983

Ewalt, D R; Bricker, B J

2000-08-01

196

Paenibacillus barcinonensis sp. nov., a xylanase-producing bacterium isolated from a rice field in the Ebro River delta.  

PubMed

A Gram-positive, endospore-forming, xylanase-producing bacterium isolated from a rice field was studied taxonomically. The strain grows at 10-40 degrees C and in the presence of lysozyme or 5 % (w/v) NaCl. Chemotaxonomic analysis revealed that MK-7 was the predominant menaquinone of the isolated strain, while the major fatty acid was anteiso-C(15 : 0). Comparison of 16S rRNA gene sequences showed that strain BP-23(T) fell within the radiation of the cluster comprising Paenibacillus species. The highest 16S rRNA gene sequence similarities were found with Paenibacillus illinoisensis (97.4 %), Paenibacillus pabuli (97.1 %) and Paenibacillus amylolyticus (96.9 %). The DNA-DNA relatedness of strain BP-23(T) with respect to these three species was very low (32.7, 31.6 and 23.0 %, respectively). On the basis of phenotypic and genotypic data, strain BP-23(T) should be placed in the genus Paenibacillus and designated a novel species, for which the name Paenibacillus barcinonensis sp. nov. is proposed. The type strain is BP-23(T) (=CECT 7022(T)=DSM 15478(T)). PMID:15774688

Sánchez, Marta M; Fritze, Dagmar; Blanco, Ana; Spröer, Cathrin; Tindall, Brian J; Schumann, Peter; Kroppenstedt, Reiner M; Diaz, Pilar; Pastor, F I Javier

2005-03-01

197

The influence of handling and isolation postweaning on open field, exploratory and maternal behavior of female rats.  

PubMed

Fifty-three black-hooded female rats, raised from the 28th to the 128th day of life under four types of environmental conditions differing in social and handling factors, had their behavioral performance evaluated in eight tests involving exploration of a complex environment (EX) in two open field (OF) tests and in three pup-retrieving tests. These tests were held before, during and after the period of lactation of their first brood. Females differed from (previously studied) males in that environmental raising conditions had a much smaller influence, especially during the lactation period. Nevertheless, females raised in isolation tended to remain for longer times inside a protected den in the exploration tests and to have greater locomotion in the open field. Previous handling allowed a greater exploration during the first contact with the novel complex environment as well as greater activity in the open field. The presence of small pups drastically reduced the exploratory motivation, but the presence of pups more than 20 days old tended to increase it. Maternal behavior evaluated in the pup retrieval test and in the test of time for the female to leave the nest side of the double box system was markedly refractory to previous environmental influences. PMID:12020733

Genaro, Gelson; Schmidek, Werner Robert

2002-04-15

198

Diversity of Listeria monocytogenes isolates of human and food origin studied by serotyping, automated ribotyping and pulsed-field gel electrophoresis  

Microsoft Academic Search

Automated ribotyping, pulsed-field gel electrophoresis (PFGE) and serotyping were evaluated for the epidemiological study of isolates of Listeria monocytogenes collected in Finland in 1997-1999 from human blood (n ¼ 116) and the food industry (n ¼ 72). The isolates divided into six serotypes, 23 EcoRI ribotypes, 54 AscI PFGE types, and 57 final subtypes if all results were combined. The

S. Lukinmaa; K. Aarnisalo; M.-L. Suihko; A. Siitonen

2004-01-01

199

Icelandic basaltic geothermal field: A natural analog for nuclear waste isolation in basalt  

SciTech Connect

Analog studies of Icelandic geothermal fields have shown that the design of nuclear waste repositories in basalt can benefit by comparison to the data base already available from the development of these geothermal fields. A high degree of similarity exists between these two systems: their petrology, groundwater geochemistry, mineral solubilities, hydrologic parameters, temperature ranges, water-rock redox equilibria, hydrothermal pH values, and secondary mineralogies all show considerable overlap in the range of values. The experimentally-simulated hydrothermal studies of the basaltic nuclear waste repository rocks have, at this time, produced a data base that receives a strong confirmation from the Icelandic analog. Furthermore, the Icelandic analog should eventually be employed to extrapolate into higher and lower temperatures, into longer time-base chemical comparisons, and into more realistic mineral deposition studies, than have been possible in the laboratory evaluations of the nuclear waste repository designs. This eventual use of the Icelandic analog will require cooperative work with the Icelandic Geological Survey. 46 refs., 4 figs., 2 tabs.

Ulmer, G.C.; Grandstaff, D.E. (Temple Univ., Philadelphia, PA (USA). Dept. of Geology)

1984-11-21

200

Biosynthesis of compatible solutes in rhizobial strains isolated from Phaseolus vulgaris nodules in Tunisian fields  

PubMed Central

Background Associated with appropriate crop and soil management, inoculation of legumes with microbial biofertilizers can improve food legume yield and soil fertility and reduce pollution by inorganic fertilizers. Rhizospheric bacteria are subjected to osmotic stress imposed by drought and/or NaCl, two abiotic constraints frequently found in semi-arid lands. Osmostress response in bacteria involves the accumulation of small organic compounds called compatible solutes. Whereas most studies on rhizobial osmoadaptation have focussed on the model species Sinorhizobium meliloti, little is known on the osmoadaptive mechanisms used by native rhizobia, which are good sources of inoculants. In this work, we investigated the synthesis and accumulations of compatible solutes by four rhizobial strains isolated from root nodules of Phaseolus vulgaris in Tunisia, as well as by the reference strain Rhizobium tropici CIAT 899T. Results The most NaCl-tolerant strain was A. tumefaciens 10c2, followed (in decreasing order) by R. tropici CIAT 899, R. leguminosarum bv. phaseoli 31c3, R. etli 12a3 and R. gallicum bv. phaseoli 8a3. 13C- and 1H-NMR analyses showed that all Rhizobium strains synthesized trehalose whereas A. tumefaciens 10c2 synthesized mannosucrose. Glutamate synthesis was also observed in R. tropici CIAT 899, R. leguminosarum bv. phaseoli 31c3 and A. tumefaciens 10c2. When added as a carbon source, mannitol was also accumulated by all strains. Accumulation of trehalose in R. tropici CIAT 899 and of mannosucrose in A. tumefaciens 10c2 was osmoregulated, suggesting their involvement in osmotolerance. The phylogenetic analysis of the otsA gene, encoding the trehalose-6-phosphate synthase, suggested the existence of lateral transfer events. In vivo 13C labeling experiments together with genomic analysis led us to propose the uptake and conversion pathways of different carbon sources into trehalose. Collaterally, the ?-1,2-cyclic glucan from R. tropici CIAT 899 was co-extracted with the cytoplasmic compatible solutes and its chemical structure was determined. Conclusions The soil bacteria analyzed in this work accumulated mainly disaccharides in response to NaCl stress. We could not find a direct correlation between the trehalose content of the rhizobial strains and their osmotolerance, suggesting that additional osmoadaptive mechanism should be operating in the most NaCl-tolerant strain R. tropici CIAT 899. PMID:20633304

2010-01-01

201

Use of Pulsed-Field Gel Electrophoresis To Characterize the Heterogeneity and Clonality of Salmonella Isolates Obtained from the Carcasses and Feces of Swine at Slaughter  

PubMed Central

Salmonella enterica isolates were recovered from swine at a collaborating processing plant over a 2-month period in the spring of 2000. In the present study, molecular subtyping by pulsed-field gel electrophoresis (PFGE) was performed on the 581 confirmed Salmonella isolates from the 84 Salmonella-positive samples obtained from the previous study. A total of 32 different PFGE pulsotypes were observed visually, and a BioNumerics software analysis clustered those pulsotypes into 12 PFGE groups. The B, F, and G groups predominated throughout the sampling period and were isolated from 39, 22, and 13% of the swine, respectively. In addition, multiple isolates were obtained from 67 of the 84 Salmonella-positive samples, and subtyping revealed multiple PFGE profiles in 35 of these 67 (62%) samples. Both carcass and fecal isolates of Salmonella were recovered from 13 swine, resulting in “matched” samples. Molecular typing of the 252 isolates recovered from the matched samples revealed that 7 (54%) of the 13 carcasses were contaminated with Salmonella pulsotypes that were not isolated from the feces of the same animal. Conversely, from 6 of the 13 (46%) matched animals, Salmonella clonal types were isolated from the feces that were not isolated from the carcass of the same animal. These data establish that each lot of swine introduces new contaminants into the plant environment and that swine feces from one animal can contaminate many carcasses. In addition, these results indicate that the examination of multiple Salmonella isolates from positive samples is necessary to determine the variety of potential contaminants of swine carcasses during slaughter and processing. PMID:12839796

Wonderling, Laura; Pearce, Rachel; Wallace, F. Morgan; Call, Jeffrey E.; Feder, Ingrid; Tamplin, Mark; Luchansky, John B.

2003-01-01

202

Comparison of pulsed-field gel electrophoresis & repetitive sequence-based PCR methods for molecular epidemiological studies of Escherichia coli clinical isolates  

PubMed Central

Background & objectives: PFGE, rep-PCR, and MLST are widely used to identify related bacterial isolates and determine epidemiologic associations during outbreaks. This study was performed to compare the ability of repetitive sequence-based PCR (rep-PCR) and pulsed-field gel electrophoresis (PFGE) to determine the genetic relationships among Escherichia coli isolates assigned to various sequence types (STs) by two multilocus sequence typing (MLST) schemes. Methods: A total of 41 extended-spectrum ?-lactamase- (ESBL-) and/or AmpC ?-lactamase-producing E. coli clinical isolates were included in this study. MLST experiments were performed following the Achtman's MLST scheme and the Whittam's MLST scheme, respectively. Rep-PCR experiments were performed using the DiversiLab system. PFGE experiments were also performed. Results: A comparison of the two MLST methods demonstrated that these two schemes yielded compatible results. PFGE correctly segregated E. coli isolates belonging to different STs as different types, but did not group E. coli isolates belonging to the same ST in the same group. Rep-PCR accurately grouped E. coli isolates belonging to the same ST together, but this method demonstrated limited ability to discriminate between E. coli isolates belonging to different STs. Interpretation & conclusions: These results suggest that PFGE would be more effective when investigating outbreaks in a limited space, such as a specialty hospital or an intensive care unit, whereas rep-PCR should be used for nationwide or worldwide epidemiology studies. PMID:25579152

Bae, Il Kwon; Kim, Juwon; Sun, Je Young Hannah; Jeong, Seok Hoon; Kim, Yong-Rok; Wang, Kang-Kyun; Lee, Kyungwon

2014-01-01

203

Complete Genome Sequence of a Field Strain of Peste des Petits Ruminants Virus Isolated during 2010-2014 Epidemics in Senegal  

PubMed Central

Peste des petits ruminants virus (PPRV) infection is expanding and results in regular epizootic activities in Africa, the Middle East, and Asia. Here, we report the complete genome sequence of a field strain of PPRV isolated in Senegal (SnDk11I13) in 2013. PMID:25291758

Salami, Habib; Croville, Guillaume; Kwiatek, Olivier; Mariette, Jérôme; Klopp, Christophe; Valière, Sophie; Guérin, Jean-Luc; Lo, Moustapha; Thiongane, Yaya; Albina, Emmanuel

2014-01-01

204

Complete Genome Sequence of a Field Strain of Peste des Petits Ruminants Virus Isolated during 2010-2014 Epidemics in Senegal.  

PubMed

Peste des petits ruminants virus (PPRV) infection is expanding and results in regular epizootic activities in Africa, the Middle East, and Asia. Here, we report the complete genome sequence of a field strain of PPRV isolated in Senegal (SnDk11I13) in 2013. PMID:25291758

Salami, Habib; Croville, Guillaume; Kwiatek, Olivier; Mariette, Jérôme; Klopp, Christophe; Valière, Sophie; Guérin, Jean-Luc; Lo, Moustapha; Thiongane, Yaya; Albina, Emmanuel; Libeau, Geneviève

2014-01-01

205

Detection of a Bacteriophage Gene Encoding a Mu-like Portal Protein in Haemophilus parasuis Reference Strains and Field Isolates by Nested Polymerase Chain Reaction  

Technology Transfer Automated Retrieval System (TEKTRAN)

A nested PCR assay was developed to determine the presence of a gene encoding a bacteriophage Mu-like portal protein, gp29, in 15 reference strains and 31 field isolates of Haemophilus parasuis. Specific primers, based on the gene’s sequence, were utilized. A majority of the virulent reference strai...

206

Cytometric measurement of in vitro inhibition of Plasmodium falciparum field isolates by drugs: a new approach for re-invasion inhibition study  

PubMed Central

Background A flow cytometric method is proposed to study in vitro drug sensitivity of Plasmodium falciparum. Standard [3H]-hypoxanthine incorporation assay gives only information on inhibition of maturation by drugs. This method is usable on field isolates and provides data on both inhibition of maturation and re-invasion. Methods The method is based on the staining of parasites with hydroethidine (HE) and thiazole orange (TO) which allow differential identification of early, trophozoite and late stage of the parasite by flow cytometry. Late stages of the parasites are obtained by incubation in culture for 24 hours. Reinvasion is followed by culturing parasitized red blood cells for 24 h more. Results Compared to the standard [3H]-hypoxanthine incorporation assay, it gave similar results as expressed by 50% inhibitory concentrations for chloroquine of laboratory strains and “fieldisolates. The effect of quinine on the schizont-ring transition was also explored using this method. First data on the inhibition of re-invasion induced by quinine are presented for both P. falciparum-cultured strains and field isolates. Discussion This method is simple to use event for field isolate study. It is suitable to analyse effect of drugs on steps of the parasite life cycle different for the maturation one. Using this method quinine was found to have a inhibitory effect on re-invasion of red cells by Plasmodium. PMID:24649924

2014-01-01

207

Relationship between aggressiveness of Stagonospora sp. isolates on field and hedge bindweeds, and in vitro production of fungal metabolites cercosporin, elsinochrome A and leptosphaerodione  

Microsoft Academic Search

Stagonospora convolvuli LA39, an effective biocontrol agent of Convolvulus arvensis (field bindweed) and Calystegia sepium (hedge bindweed) produces phytotoxic metabolites leptosphaerodione and elsinochrome A. Stagonospora isolate 214Caa produces the toxin cercosporin. If toxic metabolite production is not linked to the pathogenic ability of the fungus on bindweeds, selection of aggressive strains with limited or no production of the metabolites would

Monday O. Ahonsi; Monika Maurhofer; Désirée Boss; Geneviève Défago

2005-01-01

208

Rethinking the Niche of Upper-Atmosphere Bacteria: Draft Genome Sequences of Bacillus aryabhattai C765 and Bacillus aerophilus C772, Isolated from Rice Fields  

PubMed Central

Here, we report two genome sequences of endospore-forming bacteria isolated from the rice fields of Comporta, Portugal, identified as Bacillus aryabhattai C765 and Bacillus aerophilus C772. Both species were previously identified in air samples from the upper atmosphere, but our findings suggest their presence in a wider range of environmental niches. PMID:25858824

Brito, Patrícia H.; Serrano, Mónica

2015-01-01

209

USE OF PULSED-FIELD GEL ELECTROPHORESIS TO CHARACTERIZE THE HETEROGENEITY AND CLONALITY OF SALMONELLA ISOLATES OBTAINED FROM THE CARCASS AND FECES OF SWINE AT SLAUGHTER  

Technology Transfer Automated Retrieval System (TEKTRAN)

In a previous study, Salmonella were recovered from swine at a collaborating processing plant over a two month period in the spring of 2000. In the present study, molecular subtyping by pulsed-field gel electrophoresis (PFGE) was performed on the 581 confirmed Salmonella isolates from the 84 Salmon...

210

Isolation of halophilic and halotolerant bacteria from a Japanese salt field and comparison of the partial 16S rRNA gene sequence of an extremely halophilic isolate with those of other extreme halophiles  

Microsoft Academic Search

Halophilic and halotolerant bacteria were isolated from soil samples of a Japanese salt field, an environment where salt concentrations vary annually. From 1 g of each of the five samples collected, over 1×103 bacterial colonies (colony forming units (cfu)g-1) grew on agar medium containing 2M Na+. In contrast, 0–4 bacterial colonies (cfu g-1) were observed on agar medium containing 4M

Tomonori Takashina; Kiyotaka Otozati; Tetsuo Hamamoto; Koki Horikoshi

1994-01-01

211

Temporal and spatial distribution of Cronobacter isolates in a milk powder processing plant determined by pulsed-field gel electrophoresis.  

PubMed

A milk powder processing line was sampled for the presence of Enterobacteriaceae and the opportunistic neonatal pathogen Cronobacter at six different sampling sites during an 11-month period. The highest number of Enterobacteriaceae-positive samples was recovered from the raw milk concentrate before pasteurization (78.2%) and from nonproduct samples of the processing line (86.5%), which included swabs from the drying tower and screw conveyers, swabs from the explosion chamber, waste water after the automated cleaning-in-place procedure, air filter cut-outs, and floor samples underneath the outlet of the packaging machine. The prepackaged and packaged final product was contaminated at a rate of 6.6% and 7.1%, respectively. The prevalence of Cronobacter in the prefinal product and the prepackaged and packaged final product was 14.3%, 3.8%, and 2.1%, respectively. Pulsed-field gel electrophoresis (PFGE) analysis of 133 Cronobacter isolates yielded 40 different PFGE profiles. Long-term persistence in the processing line of some of these PFGE profiles was observed. Comparison of the PFGE profiles recovered at different sampling sites revealed the supply air as a potential source for extrinsic Cronobacter contamination. In addition, recovery of the same PFGE profiles before and after CIP events followed by heat treatment indicated the inefficiency of these hygiene measures to completely eliminate Cronobacter from all areas of the processing line. This information provides an essential basis for developing control and prevention strategies concerning this opportunistic pathogen. PMID:19245339

Hein, Ingeborg; Gadzov, Boris; Schoder, Dagmar; Foissy, Helmut; Malorny, Burkhard; Wagner, Martin

2009-03-01

212

Insecticide Resistance Alleles Affect Vector Competence of Anopheles gambiae s.s. for Plasmodium falciparum Field Isolates  

PubMed Central

The widespread insecticide resistance raises concerns for vector control implementation and sustainability particularly for the control of the main vector of human malaria, Anopheles gambiae sensu stricto. However, the extent to which insecticide resistance mechanisms interfere with the development of the malignant malaria parasite in its vector and their impact on overall malaria transmission remains unknown. We explore the impact of insecticide resistance on the outcome of Plasmodium falciparum infection in its natural vector using three An. gambiae strains sharing a common genetic background, one susceptible to insecticides and two resistant, one homozygous for the ace-1R mutation and one for the kdr mutation. Experimental infections of the three strains were conducted in parallel with field isolates of P. falciparum from Burkina Faso (West Africa) by direct membrane feeding assays. Both insecticide resistant mutations influence the outcome of malaria infection by increasing the prevalence of infection. In contrast, the kdr resistant allele is associated with reduced parasite burden in infected individuals at the oocyst stage, when compared to the susceptible strain, while the ace-1R resistant allele showing no such association. Thus insecticide resistance, which is particularly problematic for malaria control efforts, impacts vector competence towards P. falciparum and probably parasite transmission through increased sporozoite prevalence in kdr resistant mosquitoes. These results are of great concern for the epidemiology of malaria considering the widespread pyrethroid resistance currently observed in Sub-Saharan Africa and the efforts deployed to control the disease. PMID:23704944

Alout, Haoues; Ndam, Nicaise Tuikue; Sandeu, Marcel Maurice; Djégbe, Innocent; Chandre, Fabrice; Dabiré, Roch Kounbobr; Djogbénou, Luc Salako; Corbel, Vincent; Cohuet, Anna

2013-01-01

213

Psychrobium conchae gen. nov., sp. nov., a psychrophilic marine bacterium isolated from the Iheya North hydrothermal field.  

PubMed

A novel psychrophilic, marine, bacterial strain designated BJ-1(T) was isolated from the Iheya North hydrothermal field in the Okinawa Trough off Japan. Cells were Gram-negative, rod-shaped, non-spore-forming, aerobic chemo-organotrophs and motile by means of a single polar flagellum. Growth occurred at temperatures below 16 °C, with the optimum between 9 and 12 °C. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that the closest relatives of strain BJ-1(T) were Shewanella denitrificans OS-217(T) (93.5% similarity), Shewanella profunda DSM 15900(T) (92.9%), Shewanella gaetbuli TF-27(T) (92.9%), Paraferrimonas sedimenticola Mok-106(T) (92.1%) and Ferrimonas kyonanensis Asr22-7(T) (91.7%). The major respiratory quinone was Q-8. The predominant fatty acids were C(16:1)?7c and C(16:0). The G+C content of the novel strain was 40.5 mol%. Based on phylogenetic, phenotypic and chemotaxonomic evidence, it is proposed that strain BJ-1(T) represents a novel species in a new genus, for which the name Psychrobium conchae gen. nov., sp. nov. is proposed. The type strain of Psychrobium conchae is BJ-1(T) (?=JCM 30103(T)?=DSM 28701(T)). PMID:25096326

Nogi, Yuichi; Abe, Mariko; Kawagucci, Shinsuke; Hirayama, Hisako

2014-11-01

214

Sequence determination of the nucleocapsid protein gene of the porcine epidemic diarrhoea virus confirms that this virus is a coronavirus related to human coronavirus 229E and porcine transmissible gastroenteritis virus  

Microsoft Academic Search

The nucleotide sequence of 1.7 kbp cDNA, comprising the region nearest the 3' end of the genome of the porcine epidemic diarrhoea virus (PEDV), has been independently determined for two European isolates of PEDV. Almost identical results were obtained for the two isolates, which were derived from cases of PEDV infection in Belgium and Britain in 1977 and 1987, respectively.

Anne Bridgen; Mariela Duarte; Kurt Tobler; Hubert Laude; Mathias Ackermann

1993-01-01

215

Characterization of Fusarium isolates from asparagus fields in southwestern Ontario and influence of soil organic amendments on Fusarium crown and root rot.  

PubMed

Fusarium crown and root rot (FCRR) of asparagus has a complex etiology with several soilborne Fusarium spp. as causal agents. Ninety-three Fusarium isolates, obtained from plant and soil samples collected from commercial asparagus fields in southwestern Ontario with a history of FCRR, were identified as Fusarium oxysporum (65.5%), F. proliferatum (18.3%), F. solani (6.4%), F. acuminatum (6.4%), and F. redolens (3.2%) based on morphological or cultural characteristics and polymerase chain reaction (PCR) analysis with species-specific primers. The intersimple-sequence repeat PCR analysis of the field isolates revealed considerable variability among the isolates belonging to different Fusarium spp. In the in vitro pathogenicity screening tests, 50% of the field isolates were pathogenic to asparagus, and 22% of the isolates caused the most severe symptoms on asparagus. The management of FCRR with soil organic amendments of pelleted poultry manure (PPM), olive residue compost, and fish emulsion was evaluated in a greenhouse using three asparagus cultivars of different susceptibility in soils infested with two of the pathogenic isolates (F. oxysporum Fo-1.5 and F. solani Fs-1.12). Lower FCRR symptom severity and higher plant weights were observed for most treatments on 'Jersey Giant' and 'Grande' but not on 'Mary Washington'. On all three cultivars, 1% PPM consistently reduced FCRR severity by 42 to 96% and increased plant weights by 77 to 152% compared with the Fusarium control treatment. Populations of Fusarium and total bacteria were enumerated after 1, 3, 7, and 14 days of soil amendment. In amended soils, the population of Fusarium spp. gradually decreased while the population of total culturable bacteria increased. These results indicate that soil organic amendments, especially PPM, can decrease disease severity and promote plant growth, possibly by decreasing pathogen population and enhancing bacterial activity in the soil. PMID:24261409

Borrego-Benjumea, Ana; Basallote-Ureba, María J; Melero-Vara, José M; Abbasi, Pervaiz A

2014-04-01

216

The complete genome sequence of the dominant Sinorhizobium meliloti field isolate SM11 extends the S. meliloti pan-genome.  

PubMed

Isolates of the symbiotic nitrogen-fixing species Sinorhizobium meliloti usually contain a chromosome and two large megaplasmids encoding functions that are absolutely required for the specific interaction of the microsymbiont with corresponding host plants leading to an effective symbiosis. The complete genome sequence, including the megaplasmids pSmeSM11c (related to pSymA) and pSmeSM11d (related to pSymB), was established for the dominant, indigenous S. meliloti strain SM11 that had been isolated during a long-term field release experiment with genetically modified S. meliloti strains. The chromosome, the largest replicon of S. meliloti SM11, is 3,908,022bp in size and codes for 3785 predicted protein coding sequences. The size of megaplasmid pSmeSM11c is 1,633,319bp and it contains 1760 predicted protein coding sequences whereas megaplasmid pSmeSM11d is 1,632,395bp in size and comprises 1548 predicted coding sequences. The gene content of the SM11 chromosome is quite similar to that of the reference strain S. meliloti Rm1021. Comparison of pSmeSM11c to pSymA of the reference strain revealed that many gene regions of these replicons are variable, supporting the assessment that pSymA is a major hot-spot for intra-specific differentiation. Plasmids pSymA and pSmeSM11c both encode unique genes. Large gene regions of pSmeSM11c are closely related to corresponding parts of Sinorhizobium medicae WSM419 plasmids. Moreover, pSmeSM11c encodes further novel gene regions, e.g. additional plasmid survival genes (partition, mobilisation and conjugative transfer genes), acdS encoding 1-aminocyclopropane-1-carboxylate deaminase involved in modulation of the phytohormone ethylene level and genes having predicted functions in degradative capabilities, stress response, amino acid metabolism and associated pathways. In contrast to Rm1021 pSymA and pSmeSM11c, megaplasmid pSymB of strain Rm1021 and pSmeSM11d are highly conserved showing extensive synteny with only few rearrangements. Most remarkably, pSmeSM11b contains a new gene cluster predicted to be involved in polysaccharide biosynthesis. Compilation of the S. meliloti SM11 genome sequence contributes to an extension of the S. meliloti pan-genome. PMID:21396969

Schneiker-Bekel, Susanne; Wibberg, Daniel; Bekel, Thomas; Blom, Jochen; Linke, Burkhard; Neuweger, Heiko; Stiens, Michael; Vorhölter, Frank-Jörg; Weidner, Stefan; Goesmann, Alexander; Pühler, Alfred; Schlüter, Andreas

2011-08-20

217

Generating elliptically polarized isolated attosecond pulses from the 2p0 state of He+ with a linearly polarized two-color field  

NASA Astrophysics Data System (ADS)

We theoretically investigate the generation of elliptically polarized isolated attosecond pulses from He+ prepared in an initial 2p0 state with a linearly polarized two-color field. It is shown that the elliptically polarized broadband supercontinuum can be produced via controlling the acceleration step of high-order harmonic generation using a two-color field. Then elliptically polarized isolated attosecond pulses can be obtained by filtering the supercontinuum. In addition, we find that the ellipticity of attosecond pulses corresponding to the short trajectory is larger than that corresponding to the long trajectory for all the polarization directions of the driving field. Further analysis reveals that the influence of the Coulomb effect to the dynamics of the continuum electrons is responsible for the difference.

Du, Hongchuan; Xue, Shan; Wang, Huiqiao; Wen, Yizhen; Hu, Bitao

2015-03-01

218

Overexpression of ShCYP51B and ShatrD in Sclerotinia homoeocarpa Isolates Exhibiting Practical Field Resistance to a Demethylation Inhibitor Fungicide  

PubMed Central

We investigated genetic factors that govern the reduced propiconazole sensitivity of Sclerotinia homoeocarpa field isolates collected during a 2-year field efficacy study on dollar spot disease of turf in five New England sites. These isolates displayed a >50-fold range of in vitro sensitivity to a sterol demethylation inhibitor (DMI) fungicide, propiconazole, making them ideal for investigations of genetic mechanisms of reduced DMI sensitivity. The CYP51 gene homolog in S. homoeocarpa (ShCYP51B), encoding the enzyme target of DMIs, is likely a minor genetic factor for reduced propiconazole sensitivity, since there were no differences in constitutive relative expression (RE) values and only 2-fold-higher induced RE values for insensitive than for sensitive isolate groups. Next, we mined RNA-Seq transcriptome data for additional genetic factors and found evidence for the overexpression of a homolog of Botrytis cinerea atrD (BcatrD), ShatrD, a known efflux transporter of DMI fungicides. The ShatrD gene showed much higher constitutive and induced RE values for insensitive isolates. Several polymorphisms were found upstream of ShatrD but were not definitively linked to overexpression. The screening of constitutive RE values of ShCYP51B and ShatrD in isolates from two golf courses that exhibited practical field resistance to propiconazole uncovered evidence for significant population-specific overexpression of both genes. However, linear regression demonstrated that the RE of ShatrD displays a more significant relationship with propiconazole sensitivity than that of ShCYP51B. In summary, our results suggest that efflux is a major determinant of the reduced DMI sensitivity of S. homoeocarpa genotypes in New England, which may have implications for the emergence of practical field resistance in this important turfgrass pathogen. PMID:22798361

Hulvey, Jon; Popko, James T.; Sang, Hyunkyu; Berg, Andrew

2012-01-01

219

Development of a Pulsed-Field Gel Electrophoresis (PFGE) method for molecular typing of clinical isolates of Arcanobacterium haemolyticum.  

PubMed

We developed a two-block PFGE method to study molecular variation among clinical isolates of Arcanobacterium haemolyticum, an often overlooked human pathogen. Three main macrorestriction profiles were defined among 15 isolates. PFGE was an objective method for characterizing A. haemolyticum and may be useful in molecular epidemiological studies of this organism. PMID:21689692

Flores, Aurea E; Diedrick, Michelle J; Ferrieri, Patricia

2011-09-01

220

Reproductive isolation revealed in preliminary crossbreeding experiments using field collected Triatoma dimidiata (Hemiptera: Reduviidae) from three ITS-2 defined groups.  

PubMed

Triatoma dimidiata, a Chagas disease vector distributed in Mexico, Central America, Colombia, Venezuela, Peru and Ecuador, has been studied using genetic markers and four groups have been defined by ITS-2 sequences: 1A, 1B, 2 and 3. To gather evidence on the divergence and reproductive isolation among T. dimidiata ITS-2 groups, we carried out 15 crossbreeding experiments with field-collected sylvan and domestic T. dimidiata from Guatemala where three groups are found: 1A, 2 and 3. Reciprocal crosses between individuals from groups 1A and 2, and a cross between group 2 individuals from different habitats, produced an average 129.78±42.29 eggs with hatching success ranging from 31.6 to 90.1%. The offspring of these crosses reached the adult stage, and crosses between F1 insects produced eggs. These results suggest that there are no pre- or post-zygotic reproductive barriers between groups 1A and 2, or within group 2. Crosses between group 3 females and males from groups 1A or 2 produced on average 85.67±30.26 eggs and none of them hatched. These results support the existence of pre-zygotic barriers between T. dimidiata group 3 and groups 1A and 2. The group 3 individuals were collected in sylvatic environments in Yaxha, Peten, Guatemala. Previously, distinct chromosomal characteristics (cytotype 3) were described in individuals from this population. Based on this evidence we suggest that this population is divergent at the species level from other T. dimidiata populations. PMID:24041592

García, Mauricio; Menes, Marianela; Dorn, Patricia L; Monroy, Carlota; Richards, Bethany; Panzera, Francisco; Bustamante, Dulce María

2013-12-01

221

Polyclonal infections due to Mycobacterium avium complex in patients with AIDS detected by pulsed-field gel electrophoresis of sequential clinical isolates.  

PubMed Central

Invasive infection with organisms of the Mycobacterium avium complex (MAC) is common among patients with advanced human immunodeficiency virus infection. In previous studies, we analyzed multiple individual colonies of MAC isolated from specimens obtained at the same time and observed that 14 to 20% of patients are simultaneously infected with more than one strain. In this study, we examined sequential isolates from 12 patients with AIDS who had two or more MAC isolates available from clinical specimens collected more than 1 week apart; the intervals between the first and last specimens ranged from 8 to 192 (median, 46) days. For each isolate, restriction digests of genomic DNA were analyzed by pulsed-field gel electrophoresis; DNA was prepared by using a protocol, described here in detail, which had been optimized for conditions of bacterial growth and lysis. The pulsed-field gel electrophoresis analysis identified four patients (33%) infected with two different MAC strains. Both M. avium and M. intracellulare were cultured from blood specimens from two patients. In each of the four patients, the second strain was identified from a culture taken within 14 days of the initial study isolate, and in three of these patients, the first strain was detected again in a subsequent culture. These observations suggest that the presence of two different strains among isolates from sequential cultures may reflect ongoing polyclonal infection. We conclude that polyclonal infection with MAC is common among patients with AIDS. The identification of such infections may be critical in the development of effective treatments. Images PMID:7929773

Slutsky, A M; Arbeit, R D; Barber, T W; Rich, J; von Reyn, C F; Pieciak, W; Barlow, M A; Maslow, J N

1994-01-01

222

Repression of Flagella Is a Common Trait in Field Isolates of Salmonella enterica Serovar Dublin and Is Associated with Invasive Human Infections  

PubMed Central

The nontyphoidal Salmonella enterica serovar Dublin is adapted to cattle but infrequently infects humans, very often resulting in invasive infections with high levels of morbidity and mortality. A Salmonella-induced intestinal acute inflammatory response is postulated as a mechanism to prevent bacterial dissemination to systemic sites. In S. enterica serovar Typhimurium, flagella contribute to this response by providing motility and FliC-mediated activation of pattern recognition receptors. In this study, we found 4 Salmonella enterica isolates, with the antigenic formula 9,12:?:?, that, based on fliC sequence and multilocus sequence type (MLST) analyses, are aflagellate S. Dublin isolates. Interestingly, all were obtained from human bloodstream infections. Thus, we investigated the potential role of flagella in the unusual invasiveness exhibited by S. Dublin in humans by analyzing flagellation and proinflammatory properties of a collection of 10 S. Dublin human clinical isolates. We found that 4 of 7 blood isolates were aflagellate due to significantly reduced levels of fliC expression, whereas all 3 isolates from other sources were flagellated. Lack of flagella correlated with a reduced ability of triggering interleukin-8 (IL-8) and CCL20 chemokine expression in human intestinal Caco-2 cells and with reduced early inflammation in the ceca of streptomycin-pretreated C57/BL6 mice. These results indicate that flagella contribute to the host intestinal inflammatory response to Salmonella serovar Dublin and suggest that their absence may contribute to its systemic dissemination through dampening of the gut immune response. Analysis of FliC production in a collection of cattle isolates indicated that the aflagellate phenotype is widely distributed in field isolates of S. Dublin. PMID:24421045

Sasías, Sebastián; Martínez, Arací; Betancor, Laura; Estevez, Verónica; Scavone, Paola; Bielli, Alejandro; Sirok, Alfredo; Chabalgoity, José Alejandro

2014-01-01

223

Thiobacillus prosperus sp. nov., represents a new group of halotolerant metal-mobilizing bacteria isolated from a marine geothermal field  

Microsoft Academic Search

From the shallow geothermally heated seafloor at the beach of Porto di Levante (Vulcano, Italy) 8 strains of long, tiny rods were isolated, which represent the first marine metal-mobilizing bacteria. Cells are Gram negative. They grow in a temperature range between 23 and 41°C with an optimum around 37°C at a salt concentration of up to 6.0% NaCl. The isolates

Harald Huber; Karl O. Stetter

1989-01-01

224

Validation of the Abbreviated Brucella AMOS PCR as a Rapid Screening Method for Differentiation of Brucella abortus Field Strain Isolates and the Vaccine Strains, 19 and RB51  

Microsoft Academic Search

The Brucella AMOS PCR assay was previously developed to identify and differentiate specific Brucella species. In this study, an abbreviated Brucella AMOS PCR test was evaluated to determine its accuracy in differentiating Brucella abortus into three categories: field strains, vaccine strain 19 (S19), and vaccine strain RB51\\/parent strain 2308 (S2308). Two hundred thirty-one isolates were identified and tested by the

DARLA R. EWALT; BETSY J. BRICKER

2000-01-01

225

Strain identification of probiotic Lactobacillus casei-related isolates with randomly amplified polymorphic DNA and pulsed-field gel electrophoresis methods  

Microsoft Academic Search

Typing of reference strains and isolates identified as Lactobacillus casei, Lactobacillus paracasei or Lactobacillus rhamnosus was carried out using randomly amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) analyses. Strains of L. paracasei were mainly grouped in the same cluster as those of L. casei. The RAPD fingerprints of strains ATCC 393 and ATCC 15820 differ from those of the L. rhamnosus

Denis Roy; Pierre Ward; Daniel Vincent

1999-01-01

226

Pulsed-Field Gel Electrophoresis Typing of Oxacillin-Resistant Staphylococcus aureus Isolates from the United States: Establishing a National Database  

Microsoft Academic Search

Received 2 June 2003\\/Returned for modification 10 July 2003\\/Accepted 22 August 2003 Oxacillin-resistant Staphylococcus aureus (ORSA) is a virulent pathogen responsible for both health care- associated and community onset disease. We used SmaI-digested genomic DNA separated by pulsed-field gel electrophoresis (PFGE) to characterize 957 S. aureus isolates and establish a database of PFGE patterns. In addition to PFGE patterns of

Linda K. McDougal; Christine D. Steward; George E. Killgore; Jasmine M. Chaitram; Sigrid K. McAllister; Fred C. Tenover

2003-01-01

227

Selection of quantum path in high-order harmonics and isolated sub-100 attosecond generation in few-cycle spatially inhomogeneous laser fields  

NASA Astrophysics Data System (ADS)

We theoretically study the selection of the quantum path in high-order harmonics (HHG) and isolated attosecond pulse generation from a one-dimensional (1D) model of a molecule in few-cycle inhomogeneous laser fields. We show that the inhomogeneity of the laser fields play an important role in the HHG process. The cutoff of the harmonics can be extended remarkably, and the harmonic spectrum becomes smooth and has fewer modulations. We investigate the time-frequency profile of the time-dependent dipole, which shows that the short quantum path is enhanced and the long quantum path disappears in spatially inhomogeneous fields. The semi-classical three-step model is also applied to illustrate the physical mechanism of HHG. The influence of driving field carrier-envelop phase (CEP) on HHG is also discussed. By superposing a series of properly selected harmonics, an isolated attosecond pulse (IAP) with duration 53 as can be obtained by a 15-fs, 1600-nm laser pulse with the parameter ? = 0.0013 (? is the parameter that determines the order of inhomogeneity of the laser field). Project supported by the National Natural Science Foundation of China (Grant Nos. 11174108, 11104108, and 11271158).

Ge, Xin-Lei; Du, Hui; Wang, Qun; Guo, Jing; Liu, Xue-Shen

2015-02-01

228

Prevalence of Stx phages in environments of a pig farm and lysogenic infection of the field E. coli O157 isolates with a recombinant converting Phage.  

PubMed

The prevalence and nature of Shiga toxin (Stx)-producing Escherichia coli (STEC) and Stx phage were investigated in 720 swine fecal samples randomly collected from a commercial breeding pig farm in China over a 1-year surveillance period. Eight STEC O157 (1.1%), 33 STEC non-O157 (4.6%), and two stx-negative O157 (0.3%) isolates were identified. Fecal filtrates were screened directly for Stx phages using E. coli K-12 derivative strains MC1061 as indicator, yielding 15 Stx1 and 57 Stx2 phages. One Stx1 and eight Stx2 phages were obtained following norfloxacin induction of the eight field STEC O157 isolates. All Stx1 phages had hexagonal heads with long tails, while Stx2 phages had three different morphologies. Notably, most of field STEC O157 isolates released more free phages and Stx toxin after induction with ciprofloxacin. Furthermore, upon infection with the recombinant phage ?Min27(?stx::cat), E. coli laboratory strains produced both lysogenic and lytic phage, whereas two of the eight O157 STEC isolates produced only lysogens. The lysogens from laboratory strains produced infectious particles similar to ?Min27. Similarly, the lysogens from the STEC O157 isolates released Stx phage too, although free ?Min27(?stx::cat) particles were not detected. Collectively, our results reveal that breeding pig farms could be important reservoirs for Stx phages and that residual antibacterial agents may enhance the release of Stx phages and the expression of Stx. PMID:20697714

Yan, Yaxian; Shi, Yibo; Cao, Dongmei; Meng, Xiangpeng; Xia, Luming; Sun, Jianhe

2011-02-01

229

Intraspecies polymorphism of vsp genes and expression profiles of variable surface protein antigens (Vsps) in field isolates of Mycoplasma bovis.  

PubMed

To assess the extent of interstrain variation, 50 isolates of Mycoplasma (M.) bovis including the type strain PG45 were examined for the presence of a family of variable membrane surface lipoproteins (Vsps) and their genes. Southern hybridization using a genomic fragment carrying three distinct vsp genes (vspAEF) revealed a striking heterogeneity, with only 2/50 strains having identical banding patterns. Cluster analysis of the data showed that most isolates from interrelated herds (groups 1, 2 and 3) were combined in a cluster of 50% homology, while isolates from distinct geographical regions (groups 4, 5 and 6) were linked only at 18% homology. Vsp antigen expression was monitored by Western immunoblotting using four specific monoclonal antibodies (MAbs). Resembling the findings at the DNA level, interstrain variation of Vsp expression among groups 1-3 was less pronounced than among non-interrelated isolates from groups 4-6. Ten out of 50 strains did not hybridize with the vspAEF gene probe at high-stringency conditions, 8/50 failed to react with any of the Vsp-related MAbs, and 6/50 proved negative in both assays. Interestingly, most of these isolates produced hybridization signals at low stringency suggesting major distinctions in their vsp gene structure. The extensive evidence obtained on interstrain vsp gene polymorphism and variation in Vsp expression could provide a basis for a future understanding of the pathogenic potential of individual M. bovis strains. PMID:9850998

Beier, T; Hotzel, H; Lysnyansky, I; Grajetzki, C; Heller, M; Rabeling, B; Yogev, D; Sachse, K

1998-10-01

230

In Vitro Metacyclogenesis of Leishmania (Viannia) braziliensis and Leishmania (Leishmania) amazonensis Clinical Field Isolates, as Evaluated by Morphology, Complement Resistance, and Infectivity to Human Macrophages  

PubMed Central

This study was designed to assess in vitro metacyclogenesis of Leishmania (Viannia) braziliensis and Leishmania (Leishmania) amazonensis clinical field isolates obtained from patient lesions (L. braziliensis IMG3 and PPS6m; L. amazonensis MAB6). Metacyclogenesis was evaluated by different criteria, namely, promastigote size (morphometric analysis and flow cytometry), surface modifications (loss of lectin or monoclonal antibody (mAb) binding, complement resistance), and infectivity to human macrophages. Growth curves were similar for all parasites evaluated. The various features analyzed were expressed in a high percentage of promastigotes at 6th and 10th days of culture and a low percentage at the 2nd day. However, in most isolates, these features, considered as markers of metacyclogenesis, seemed to develop with different time courses, since the percentages of metacyclic forms detected with each technique were usually different. Parasites from 6th or 10th day and those negatively selected with lectin or mAb similarly infected human macrophages. From all isolates analyzed, L. amazonensis PH8 and MAB6 showed the highest and the lowest levels of susceptibility, respectively, to leishmanicidal activity of IFN-?/LPS-activated macrophages. Our results showed that by using different techniques to evaluate different aspects of metacyclogenesis (morphological and biochemical modifications) different percentages of metacyclic promastigotes can be detected in each isolate culture. PMID:25695070

da Silva, Ildefonso Alves; Morato, Camila Imai; Quixabeira, Valéria Bernadete Leite; Pereira, Ledice Inácia de Araújo; Dorta, Miriam Leandro; de Oliveira, Milton Adriano Pelli; Horta, Maria Fátima; Ribeiro-Dias, Fátima

2015-01-01

231

Virulence and polar tube protein genetic diversity of Nosema ceranae (Microsporidia) field isolates from Northern and Southern Europe in honeybees (Apis mellifera iberiensis).  

PubMed

Infection of honeybees by the microsporidian Nosema ceranae is considered to be one of the factors underlying the increased colony losses and decreased honey production seen in recent years. However, these effects appear to differ in function of the climatic zone, the distinct beekeeping practices and the honeybee species employed. Here, we compared the response of Apis mellifera iberiensis worker bees to experimental infection with field isolates of N.?ceranae from an Oceanic climate zone in Northern Europe (Netherlands) and from a Mediterranean region of Southern Europe (Spain). We found a notable but non-significant trend (P?=?0.097) towards higher honeybee survival for bees infected with N.?ceranae from the Netherlands, although no differences were found between the two isolates in terms of anatomopathological lesions in infected ventricular cells or the morphology of the mature and immature stages of the parasite. In addition, the population genetic survey of the N. ceranae?PTP3 locus revealed high levels of genetic diversity within each isolate, evidence for meiotic recombination, and no signs of differentiation between the Dutch and Spanish populations. A cross-infection study is needed to further explore the differences in virulence observed between the two N.?ceranae populations in field conditions. PMID:24992540

Van der Zee, Romee; Gómez-Moracho, Tamara; Pisa, Lennard; Sagastume, Soledad; García-Palencia, Pilar; Maside, Xulio; Bartolomé, Carolina; Martín-Hernández, Raquel; Higes, Mariano

2014-08-01

232

Suitability of the molecular subtyping methods intergenic spacer region, direct genome restriction analysis, and pulsed-field gel electrophoresis for clinical and environmental Vibrio parahaemolyticus isolates.  

PubMed

Vibrio parahaemolyticus is the leading cause of infectious illness associated with seafood consumption in the United States. Molecular fingerprinting of strains has become a valuable research tool for understanding this pathogen. However, there are many subtyping methods available and little information on how they compare to one another. For this study, a collection of 67 oyster and 77 clinical V. parahaemolyticus isolates were analyzed by three subtyping methods--intergenic spacer region (ISR-1), direct genome restriction analysis (DGREA), and pulsed-field gel electrophoresis (PFGE)--to determine the utility of these methods for discriminatory subtyping. ISR-1 analysis, run as previously described, provided the lowest discrimination of all the methods (discriminatory index [DI]=0.8665). However, using a broader analytical range than previously reported, ISR-1 clustered isolates based on origin (oyster versus clinical) and had a DI=0.9986. DGREA provided a DI=0.9993-0.9995, but did not consistently cluster the isolates by any identifiable characteristics (origin, serotype, or virulence genotype) and ? 15% of isolates were untypeable by this method. PFGE provided a DI=0.9998 when using the combined pattern analysis of both restriction enzymes, SfiI and NotI. This analysis was more discriminatory than using either enzyme pattern alone and primarily grouped isolates by serotype, regardless of strain origin (clinical or oyster) or presence of currently accepted virulence markers. These results indicate that PFGE and ISR-1 are more reliable methods for subtyping V. parahemolyticus, rather than DGREA. Additionally, ISR-1 may provide an indication of pathogenic potential; however, more detailed studies are needed. These data highlight the diversity within V. parahaemolyticus and the need for appropriate selection of subtyping methods depending on the study objectives. PMID:24799175

Lüdeke, Catharina H M; Fischer, Markus; LaFon, Patti; Cooper, Kara; Jones, Jessica L

2014-07-01

233

Molecular epidemiology of porcine epidemic diarrhea virus in China  

Microsoft Academic Search

Since early 2006, porcine epidemic diarrhea virus (PEDV) has been reemerging in immunized swine herds. Open reading frame\\u000a 3 (ORF3) is the only accessory gene in the PEDV genome. The entire ORF3 genes of 12 PEDV field strains and one vaccine strain\\u000a were sequenced. The ORF3 genes of Chinese PEDV field strains (excluding CH\\/GSJIII\\/07) contain a single 672- or 675-nucleotide

Jianfei Chen; Chengbao Wang; Hongyan Shi; Huaji Qiu; Shengwang Liu; Xiaojin Chen; Zhibang Zhang; Li Feng

2010-01-01

234

Three-dimensional MHD simulation of FTEs produced by merging at an isolated point in a sheared magnetic field configuration  

NASA Astrophysics Data System (ADS)

We present predictions for the evolution of FTEs generated by localized bursts of reconnection on a planar magnetopause that separates a magnetosheath region of high densities and weak magnetic field from a magnetospheric region of low densities and strong magnetic field. The magnetic fields present a shear angle of 105 degrees. Reconnection forms a pair of FTEs each crossing the magnetopause in the field reversal region and bulging into the magnetosphere and magnetosheath. At their initial stage they can be characterized as flux tubes since the newly reconnected magnetic field lines are not twisted. Reconnection launches Alfvenic perturbations that propagate along the FTEs generating high-speed jets, which move the pair of FTEs in opposite directions. As the FTE moves, it displaces the ambient magnetic field and plasma producing bipolar magnetic field and plasma velocity signatures normal to the nominal magnetopause in the regions surrounding the FTE. The combination of the ambient plasma with the FTE flows generates a vortical velocity pattern around the reconnected field lines. During its evolution the FTE evolves to a flux rope configuration due to the twist of the magnetic field lines. The alfvenic perturbations propagate faster along the part of the FTE bulging into the magnetosphere than in the magnetosheath, and due to the differences between the plasma and magnetic field properties the perturbations have slightly different signatures in the two regions. As a consequence, the FTEs have different signatures depending on whether the satellite encounters the part bulging into the magnetosphere or into the magnetosheath.

Santos, J. C.; Sibeck, D. G.; Büchner, J.; Gonzalez, W. D.; Ferreira, J. L.

2014-03-01

235

Genotypic variations in field isolates of Theileria species infecting giraffes (Giraffa camelopardalis tippelskirchi and Giraffa camelopardalis reticulata) in Kenya.  

PubMed

Recently, mortalities among giraffes, attributed to infection with unique species of piroplasms were reported in South Africa. Although haemoparasites are known to occur in giraffes of Kenya, the prevalence, genetic diversity and pathogenicity of these parasites have not been investigated. In this study, blood samples from 13 giraffes in Kenya were investigated microscopically and genomic DNA extracted. PCR amplicons of the hyper-variable region 4 (V4) of Theileria spp. small subunit ribosomal RNA (18S rRNA) gene were hybridized to a panel of genus- and species-specific oligonucleotide probes by reverse line blot (RLB). Two newly designed oligonucleotide probes specific for previously identified Theileria spp. of giraffes found single infections in eight of the specimens and mixed infections in the remaining five samples. Partial 18S rRNA genes were successfully amplified from 9 samples and the PCR amplicons were cloned. A total of 28 plasmid clones representing the Kenyan isolates were analyzed in the present study and compared with those of closely-related organisms retrieved from GenBank. In agreement with RLB results, the nucleotide sequence alignment indicated the presence of mixed infections in the giraffes. In addition, sequence alignment with the obtained 18S rRNA gene sequences revealed extensive microheterogeneities within and between isolates, characterized by indels in the V4 regions and point mutations outside this region. Phylogeny with 18S rRNA gene sequences from the detected parasites and those of related organisms places Theileria of giraffes into two major groups, within which are numerous clades that include the isolates reported in South Africa. Collectively, these data suggest the existence of at least two distinct Theileria species among giraffes, and extensive genetic diversity within the two parasite groups. PMID:23792245

Githaka, Naftaly; Konnai, Satoru; Skilton, Robert; Kariuki, Edward; Kanduma, Esther; Murata, Shiro; Ohashi, Kazuhiko

2013-10-01

236

Candidate anthelmintic resistance-associated gene expression and sequence polymorphisms in a triple-resistant field isolate of Haemonchus contortus.  

PubMed

An isolate of Haemonchus contortus, UGA/2004, highly resistant to benzimidazoles, levamisole, and ivermectin was isolated from sheep at the University of Georgia, and passaged through experimentally infected goats. We measured the expression of twenty-nine mRNAs encoding drug targets and P-glycoproteins (P-gps), comparing the results to a fully susceptible laboratory passaged isolate. Expression levels of some nicotinic acetylcholine receptor mRNAs were markedly different in UGA/2004. Levels of the Hco-acr-8b mRNA, encoding a truncated subunit, were very high in resistant L3, but undetectable in susceptible larvae, with expression of the full-length Hco-acr-8a mRNA also significant increased. Expression of Hco-unc-63 and Hco-unc-29.3 mRNAs was significantly reduced in the resistant larvae. Expression of the Hco-glc-3 and Hco-glc-5 mRNAs, encoding glutamate-gated chloride channel subunits, were slightly reduced in resistant larvae. We observed significant increases in the expression of the Hco-pgp-2 and Hco-pgp-9 mRNAs in the UGA/2004 larvae, consistent with previous reports; we also saw a decrease in the levels of Hco-pgp-1 mRNA. Treatment of the larvae with ivermectin and moxidectin in vitro produced variable and inconsistent changes in P-gp mRNA levels. The sequences of the ?-tubulin isotype 1 mRNAs showed that the resistant larvae had a resistance-associated allele frequency of >95% at codon 200 and ?40% and codon 167. No changes at codon 198 were present. The presence of the truncated acr-8b mRNA may be a reliable indicator of levamisole resistance, but complex changes in gene expression associated with macrocyclic lactone resistance make the identification of a single genetic marker for this resistance difficult. PMID:21945142

Williamson, Sally M; Storey, Bob; Howell, Sue; Harper, Kate M; Kaplan, Ray M; Wolstenholme, Adrian J

2011-12-01

237

Ivermectin and moxidectin resistance characterization by larval migration inhibition test in field isolates of Cooperia spp. in beef cattle, Mato Grosso do Sul, Brazil.  

PubMed

Ivermectin (IVM) resistance of Cooperia spp. in cattle has become an increasing and global problem. The early detection of anthelmintic resistance (AR) is important to propose strategies to slow down the development of resistance and requires sensitive, reliable, economic high-throughput and practical tests. The purpose of the present study was to apply a larval migration inhibition test (LMIT) for evaluating IVM and MOX efficacy against well-characterized field isolates of Cooperia spp. infecting cattle in Brazil. Eight isolates were used for IVM and seven for MOX. The following EC50 values of IVM were observed for the isolates: susceptible, 1.16 ?mol; Nova Alvorada do Sul I, 4.09 ?mol (RF=3.52); Campo Grande BNA, 3.57 ?mol (RF=3.07); Campo Grande TBR, 4.09 ?mol (RF=3,52); Nova Alvorada do Sul II, 2.50 ?mol (RF=2.15); Bandeirantes, 11.35 ?mol (RF=9.78); Campo Grande II, 6.03 ?mol (RF=5.20); and Porto Mortinho, 8.63 ?mol (RF=7.44). For MOX, the following EC50 values were observed: susceptible, 0.75 ?mol; Campo Grande BNA, 0.93 ?mol (RF=1.24); Campo Grande TBR, 0.36 ?mol (RF=0.48); Nova Alvorada do Sul II, 2.57 ?mol (RF=3.42); Bandeirantes, 1.43 ?mol (RF=1.90); Campo Grande II, 1.08 ?mol (RF=1.44); and Porto Mortinho, 0.49 ?mol (RF=0.65). The LMIT used in the present study can be a useful tool for in vitro evaluation of IVM, but not of MOX. However, such methodology cannot be used in large-scale studies yet. The isolates of Cooperia spp. showed various degrees of resistance to IVM, though remaining susceptible to MOX. PMID:22963710

Almeida, G D; Feliz, D C; Heckler, R P; Borges, D G L; Onizuka, M K V; Tavares, L E R; Paiva, F; Borges, F A

2013-01-16

238

Molecular Typing and Epidemiological Study of Salmonella enterica Serotype Typhimurium Isolates from Cattle by Fluorescent Amplified-Fragment Length Polymorphism Fingerprinting and Pulsed-Field Gel Electrophoresis  

PubMed Central

One hundred twenty Salmonella enterica serotype Typhimurium strains, including 103 isolates from cattle gathered between 1977 and 1999 in the prefecture located on the northern-most island of Japan, were analyzed by using fluorescent amplified-fragment length polymorphism (FAFLP) and pulsed-field gel electrophoresis (PFGE) to examine the genotypic basis of the epidemic. Among these strains, there were 17 FAFLP profiles that formed four distinct clusters (A, B, C, and D). Isolates that belonged to cluster A have become increasingly common since 1992 with the increase of bovine salmonellosis caused by serotype Typhimurium. PFGE resolved 25 banding patterns that formed three distinct clusters (I, II, and III). All the isolates that belonged to FAFLP cluster A, in which all the strains of definitive phage type 104 examined were included, were grouped into PFGE cluster I. Taken together, these results indicate that clonal exchange of serotype Typhimurium has taken place since 1992, and they show a remarkable degree of homogeneity at a molecular level among contemporary isolates from cattle in this region. Moreover, we have sequenced two kinds of FAFLP markers, 142-bp and 132-bp fragments, which were identified as a polymorphic marker of strains that belonged to clusters A and C, respectively. The sequence of the 142-bp fragment shows homology with a segment of P22 phage, and that of the 132-bp fragment shows homology with a segment of traG, which is an F plasmid conjugation gene. FAFLP is apparently as well suited for epidemiological typing of serotype Typhimurium as is PFGE, and FAFLP can provide a source of molecular markers useful for studies of genetic variation in natural populations of serotype Typhimurium. PMID:11230427

Tamada, Yukihiro; Nakaoka, Yuji; Nishimori, Kei; Doi, Akira; Kumaki, Takahiro; Uemura, Nobuko; Tanaka, Kiyoshi; Makino, Sou-Ichi; Sameshima, Toshiya; Akiba, Masato; Nakazawa, Muneo; Uchida, Ikuo

2001-01-01

239

Geometric morphometrics of nine field isolates of Aedes aegypti with different resistance levels to lambda-cyhalothrin and relative fitness of one artificially selected for resistance.  

PubMed

Aedes aegypti, a mosquito closely associated with humans, is the principal vector of dengue virus which currently infects about 400 million people worldwide. Because there is no way to prevent infection, public health policies focus on vector control; but insecticide-resistance threatens them. However, most insecticide-resistant mosquito populations exhibit fitness costs in absence of insecticides, although these costs vary. Research on components of fitness that vary with insecticide-resistance can help to develop policies for effective integrated management and control. We investigated the relationships in wing size, wing shape, and natural resistance levels to lambda-cyhalothrin of nine field isolates. Also we chose one of these isolates to select in lab for resistance to the insecticide. The main life-traits parameters were assessed to investigate the possible fitness cost and its association with wing size and shape. We found that wing shape, more than wing size, was strongly correlated with resistance levels to lambda-cyhalothrin in field isolates, but founder effects of culture in the laboratory seem to change wing shape (and also wing size) more easily than artificial selection for resistance to that insecticide. Moreover, significant fitness costs were observed in response to insecticide-resistance as proved by the diminished fecundity and survival of females in the selected line and the reversion to susceptibility in 20 generations of the non-selected line. As a practical consequence, we think, mosquito control programs could benefit from this knowledge in implementing efficient strategies to prevent the evolution of resistance. In particular, the knowledge of reversion to susceptibility is important because it can help in planning better strategies of insecticide use to keep useful the few insecticide-molecules currently available. PMID:24801598

Jaramillo-O, Nicolás; Fonseca-González, Idalyd; Chaverra-Rodríguez, Duverney

2014-01-01

240

Geometric Morphometrics of Nine Field Isolates of Aedes aegypti with Different Resistance Levels to Lambda-Cyhalothrin and Relative Fitness of One Artificially Selected for Resistance  

PubMed Central

Aedes aegypti, a mosquito closely associated with humans, is the principal vector of dengue virus which currently infects about 400 million people worldwide. Because there is no way to prevent infection, public health policies focus on vector control; but insecticide-resistance threatens them. However, most insecticide-resistant mosquito populations exhibit fitness costs in absence of insecticides, although these costs vary. Research on components of fitness that vary with insecticide-resistance can help to develop policies for effective integrated management and control. We investigated the relationships in wing size, wing shape, and natural resistance levels to lambda-cyhalothrin of nine field isolates. Also we chose one of these isolates to select in lab for resistance to the insecticide. The main life-traits parameters were assessed to investigate the possible fitness cost and its association with wing size and shape. We found that wing shape, more than wing size, was strongly correlated with resistance levels to lambda-cyhalothrin in field isolates, but founder effects of culture in the laboratory seem to change wing shape (and also wing size) more easily than artificial selection for resistance to that insecticide. Moreover, significant fitness costs were observed in response to insecticide-resistance as proved by the diminished fecundity and survival of females in the selected line and the reversion to susceptibility in 20 generations of the non-selected line. As a practical consequence, we think, mosquito control programs could benefit from this knowledge in implementing efficient strategies to prevent the evolution of resistance. In particular, the knowledge of reversion to susceptibility is important because it can help in planning better strategies of insecticide use to keep useful the few insecticide-molecules currently available. PMID:24801598

Jaramillo-O., Nicolás; Fonseca-González, Idalyd; Chaverra-Rodríguez, Duverney

2014-01-01

241

Virulence of Mexican isolates of entomopathogenic fungi upon Rhipicephalus-Boophilus microplus larvae and the efficacy of conidia formulations to reduce larval tick density under field conditions  

Technology Transfer Automated Retrieval System (TEKTRAN)

The first objective was laboratory evaluation of the virulence of 53 Mexican isolates of fungi against larvae of Rhipicephalus (Boophilus) microplus. Thirty three isolates of Metarhizium anisopliae var. anisopliae (Metschnickoff) Sorokin (Hypocreales: Clavicipitaceae) and 20 isolates of Isaria (Paec...

242

Phenotypic variability among strains of Pasteurella multocida isolated from avian, bovine, caprine, leporine and ovine origin  

Microsoft Academic Search

Phenotypic diversity among 69 field isolates plus 3 vaccine strains previously identified as Pasteurella multocida were investigated by extended phenotypic characterization. The field isolates were obtained in Nigeria from chickens (15 isolates), quail (5 isolates), cattle (31 isolates), goats (7 isolates), sheep (8 isolates), rabbits (3 isolates) and the vaccine strains (3 isolates), which are used as prophylaxis against fowl

Sarah O. Ekundayo; Moses O. Odugbo; Atanda O. Olabode; Philip A. Okewole

2008-01-01

243

Isolated-attosecond-pulse generation from asymmetric molecules with an {omega}+2{omega}/3 multicycle two-color field  

SciTech Connect

The high harmonic generation from asymmetric molecules with an {omega}+2{omega}/3 multicycle bichromatic laser pulse has been investigated. It is shown that the ionization asymmetry in consecutive half optical cycles for asymmetric molecules is further enhanced since the 2{omega}/3 control laser pulse further enhances the amplitude of the ionization peak at the center of the laser pulse. The 2{omega}/3 control laser pulse also significantly enlarges the difference of the photon energies emitted from the ejected electron in the half optical cycle at the central laser pulse and its next half optical cycle. In addition, a broadband supercontinuum is produced in the plateau of the spectrum, from which an isolated 90-as pulse can be directly obtained.

Li Qianguang [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China); Department of Physics, Xiaogan University, Xiaogan 432000 (China); Hong Weiyi; Zhang Qingbin; Wang Shaoyi; Lu Peixiang [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China)

2010-05-15

244

Field application of the Numobag as a portable disposable isolation unit and for treating chemical, radiological or biologically induced wounds.  

SciTech Connect

Numotech Inc. has developed the Numobag{trademark}, a disposable, lightweight, wound healing device which produces Topical Hyperbaric Oxygen Therapy (THOT). The Numobag{trademark} is cost effective and has been clinically validated to heal large skin lesions rapidly and has proven to arrest wound advancement from several insidious forms of biological attack including dermal anthrax, small pox, necrotizing fasciitis etc. The Numobag{trademark} can treat mass casualties wounded by chemical/radiological burns or damaging biological exposures. The Numobag{trademark} can be a frontline tool as an isolation unit, reducing cross-contamination and infection of medical personnel. The heightened oxygen content kills organisms on the skin and in the wound, avoids expensive hospital trash disposal procedures, and helps the flesh heal. The Numobag{trademark} requires high purity oxygen. Numotech Inc. is teaming with Sandia National Laboratories and Spektr Conversion in Russia to develop a cost effective, portable, low power oxygen generator.

Miller, Keith A.; Felton, Robert; Vaughan, Courtenay Thomas

2005-04-01

245

Implementation of an indoxacarb susceptibility monitoring program using field-collected German cockroach isolates from the United States.  

PubMed

Indoxacarb, a sodium channel-blocking insecticide, has been in widespread use for German cockroach control in the United States since 2006. A two-tiered indoxacarb susceptibility monitoring strategy was previously developed as a first step toward determining indoxacarb susceptibility levels in German cockroach field populations. This strategy entails: (tier 1) testing field-collected populations in vial bioassays at two diagnostic concentrations; and (tier 2) testing populations at three diagnostic doses in oral (feeding) bioassays with treated bait matrix. In the current study the two-tiered technique was implemented to evaluate field (n = 14) and susceptible laboratory (n = 2) strains collected from 13 different U.S. locations. Our hypothesis was that at least some of the field-collected populations would display significant survivorship in both bioassays relative to susceptible laboratory populations. In agreement with this hypothesis, significantly reduced susceptibility was detected in 13 and 7 field strains with vial and feeding bioassays, respectively. In general, the lower number of strains displaying reduced susceptibility in feeding bioassays (seven strains) supports previous findings that indoxacarb is more toxic via ingestion. Although these findings suggest a reduced risk for resistance selection via feeding on indoxacarb-containing baits, they also suggest a need for proactive resistance management with respect to both spray and bait products. PMID:23786086

Gondhalekar, Ameya D; Scherer, Clay W; Saran, Raj K; Scharf, Michael E

2013-04-01

246

Comparative analysis of genetic variability among Borrelia burgdorferi isolates from Europe and the United States by restriction enzyme analysis, gene restriction fragment length polymorphism, and pulsed-field gel electrophoresis.  

PubMed Central

The genomes of 62 North American and European Borrelia burgdorferi isolates were examined by restriction endonuclease analysis (REA), gene probe restriction fragment length polymorphism, and pulsed-field gel electrophoresis (PFGE). Hybridization of restriction fragments with the immunologically relevant 83-kDa antigen gene revealed polymorphisms and divided the isolates into three major groups. Group I included all but two of the American isolates and some of the European isolates. One of two Californian isolates (DN 127) and one Ixodes dammini isolate from New York (strain 25015), previously described as atypical, were distinct from the isolates in the three groups. Plasmid profile analysis and REA, the method with the highest level of discrimination, revealed extensive heterogeneity among isolates of the same major group. Our study demonstrates the usefulness of the 83-kDa antigen gene probe for dividing the isolates into major genogroups, whereas REA and plasmid profile analysis allow for a distinction of individual strains within these groups. Images PMID:7905881

Zingg, B C; Anderson, J F; Johnson, R C; LeFebvre, R B

1993-01-01

247

Phylogenetic comparison of the S3 gene of United States prototype strains of bluetongue virus with that of field isolates from California.  

PubMed Central

To better define the molecular epidemiology of bluetongue virus (BTV) infection, the genetic characteristics and phylogenetic relationships of the S3 genes of the five U.S. prototype strains of BTV, the commercially available serotype 10 modified live virus vaccine, and 18 field isolates of BTV serotypes 10, 11, 13, and 17 obtained in California during 1980, 1981, 1989, and 1990 were determined. With the exception of the S3 gene of the U.S. prototype strain of BTV serotype 2 (BTV 2), these viruses had an overall sequence homology of between 95 and 100%. Phylogenetic analyses segregated the prototype U.S. BTV 2 strain to a unique branch (100% bootstrap value), whereas the rest of the viruses clustered in two main monophyletic groups that were not correlated with their serotype, year of isolation, or geographical origin. The lack of consistent association between S3 gene sequence and virus serotype likely is a consequence of reassortment of BTV gene segments during natural mixed infections of vertebrate and invertebrate hosts. The prototype strain of BTV 13, which is considered an introduction to the U.S. like BTV 2, presents an S3 gene which is highly homologous to those of some isolates of BTV 10 and especially to that of the vaccine strain. This finding strongly suggests that the U.S. prototype strain of BTV 13 is a natural reassortant. The different topologies of the phylogenetic trees of the L2 and S3 genes of the various viruses indicate that these two genome segments evolve independently. We conclude that the S3 gene segment of populations of BTV in California is formed by different consensus sequences which cocirculate and which cannot be grouped by serotype. PMID:8764098

de Mattos, C C; de Mattos, C A; MacLachlan, N J; Giavedoni, L D; Yilma, T; Osburn, B I

1996-01-01

248

Microbial diversity in Los Azufres geothermal field (Michoacán, Mexico) and isolation of representative sulfate and sulfur reducers.  

PubMed

Los Azufres spa consists of a hydrothermal spring system in the Mexican Volcanic Axis. Five samples (two microbial mats, two mud pools and one cenote water), characterized by high acidity (pH between 1 and 3) and temperatures varying from 27 to 87 °C, were investigated for their microbial diversity by Terminal-Restriction Fragment Length Polymorphism (T-RFLP) and 16S rRNA gene library analyses. These data are the first to describe microbial diversity from Los Azufres geothermal belt. The data obtained from both approaches suggested a low bacterial diversity in all five samples. Despite their proximity, the sampling points differed by their physico-chemical conditions (mainly temperature and matrix type) and thus exhibited different dominant bacterial populations: anoxygenic phototrophs related to the genus Rhodobacter in the biomats, colorless sulfur oxidizers Acidithiobacillus sp. in the warm mud and water samples, and Lyzobacter sp.-related populations in the hot mud sample (87 °C). Molecular data also allowed the detection of sulfate and sulfur reducers related to Thermodesulfobium and Desulfurella genera. Several strains affiliated to both genera were enriched or isolated from the mesophilic mud sample. A feature common to all samples was the dominance of bacteria involved in sulfur and iron biogeochemical cycles (Rhodobacter, Acidithiobacillus, Thiomonas, Desulfurella and Thermodesulfobium genera). PMID:24446065

Brito, Elcia M S; Villegas-Negrete, Norberto; Sotelo-González, Irene A; Caretta, César A; Goñi-Urriza, Marisol; Gassie, Claire; Hakil, Florence; Colin, Yannick; Duran, Robert; Gutiérrez-Corona, Felix; Piñón-Castillo, Hilda A; Cuevas-Rodríguez, Germán; Malm, Olaf; Torres, João P M; Fahy, Anne; Reyna-López, Georgina E; Guyoneaud, Rémy

2014-03-01

249

Response of American lobsters Homarus americanus to infection with a field isolate of Aerococcus viridans var. homari (Gaffkemia): survival and haematology.  

PubMed

American lobsters Homarus americanus were inoculated with a field isolate of the Gram-positive bacterium Aerococcus viridans var. homari, causative agent of gaffkemia, at 1 x 10(6), 1 x 10(4) or 1 x 10(2) colony forming units (CFU) kg(-1) or with sterile 3% NaCl and maintained at 10 or 15 degrees C until they died or were euthanised. Progression of disease in individual animals was monitored daily by total haemocyte count (THC) and haemolymph culture. Post-mortem examinations were performed on all lobsters. Effects of both ambient temperature and infective dose on survival time were observed. Marked bacteraemia occurred in all mortalities. Haemocytopenia (THC < 10 x 10(9) cells l(-1)) preceded death in most, but not all, mortalities. PMID:15609881

Battison, A L; Cawthorn, R J; Horney, B

2004-11-01

250

Leishmania aethiopica Field Isolates Bearing an Endosymbiontic dsRNA Virus Induce Pro-inflammatory Cytokine Response  

PubMed Central

Background Infection with Leishmania parasites causes mainly cutaneous lesions at the site of the sand fly bite. Inflammatory metastatic forms have been reported with Leishmania species such as L. braziliensis, guyanensis and aethiopica. Little is known about the factors underlying such exacerbated clinical presentations. Leishmania RNA virus (LRV) is mainly found within South American Leishmania braziliensis and guyanensis. In a mouse model of L. guyanensis infection, its presence is responsible for an hyper-inflammatory response driven by the recognition of the viral dsRNA genome by the host Toll-like Receptor 3 leading to an exacerbation of the disease. In one instance, LRV was reported outside of South America, namely in the L. major ASKH strain from Turkmenistan, suggesting that LRV appeared before the divergence of Leishmania subgenera. LRV presence inside Leishmania parasites could be one of the factors implicated in disease severity, providing rationale for LRV screening in L. aethiopica. Methodology/Principal Findings A new LRV member was identified in four L. aethiopica strains (LRV-Lae). Three LRV-Lae genomes were sequenced and compared to L. guyanensis LRV1 and L. major LRV2. LRV-Lae more closely resembled LRV2. Despite their similar genomic organization, a notable difference was observed in the region where the capsid protein and viral polymerase open reading frames overlap, with a unique ?1 situation in LRV-Lae. In vitro infection of murine macrophages showed that LRV-Lae induced a TLR3-dependent inflammatory response as previously observed for LRV1. Conclusions/Significance In this study, we report the presence of an immunogenic dsRNA virus in L. aethiopica human isolates. This is the first observation of LRV in Africa, and together with the unique description of LRV2 in Turkmenistan, it confirmed that LRV was present before the divergence of the L. (Leishmania) and (Viannia) subgenera. The potential implication of LRV-Lae on disease severity due to L. aethiopica infections is discussed. PMID:24762979

Zangger, Haroun; Hailu, Asrat; Desponds, Chantal; Lye, Lon-Fye; Akopyants, Natalia S.; Dobson, Deborah E.; Ronet, Catherine; Ghalib, Hashim; Beverley, Stephen M.; Fasel, Nicolas

2014-01-01

251

Permethrin resistance variation and susceptible reference line isolation in a field population of the mosquito, Culex quinquefasciatus (Diptera: Culicidae).  

PubMed

This study examines the genetic variations and mechanisms involved in the development of permethrin resistance in individual mosquitoes from a field population of Culex quinquefasciatus, HAmCq(G0) , and characterizes susceptible reference lines of mosquitoes with a similar genetic background to the field HAmCq(G0) strain. Six upregulated cytochrome P450 genes, CYP9M10, CYP9J34, CYP6P14, CYP9J40, CYP6AA7, and CYP4C52v1, previously identified as being upregulated in the larvae of resistant HAmCq(G8) mosquitoes were examined in the larvae of 3 strains (susceptible S-Lab, parental HAmCq(G0) and permethrin-selected highly resistant HAmCq(G8) ) and 8 HAmCq(G0) single-egg raft colonies, covering a range of levels of susceptibility/resistance to permethrin and exhibiting different variations in the expression of A and/or T alleles at the L-to-F kdr locus of the sodium channel. The 2 lines with the lowest tolerance to permethrin and bearing solely the susceptible A allele at the L-to-F kdr locus of the sodium channels, from colonies Cx_SERC5 and Cx_SERC8, showed lower or similar levels of all 6 of the P450 genes tested compared with the S-Lab strain, suggesting that these 2 lines could be used as the reference mosquitoes in future studies characterizing insecticide resistance in HAmCq mosquitoes. This study also provides a detailed investigation of the mechanisms involved in insecticide resistance in individuals within a population: individuals with elevated levels of resistance to permethrin all displayed one or more potential resistance mechanisms-either elevated levels of P450 gene expression, or L-to-F mutations in the sodium channel, or both. PMID:24357606

Yang, Ting; Liu, Nannan

2014-10-01

252

Microbial Corrosion in Linepipe Steel Under the Influence of a Sulfate-Reducing Consortium Isolated from an Oil Field  

NASA Astrophysics Data System (ADS)

This work investigates microbiologically influenced corrosion of API 5L X52 linepipe steel by a sulfate-reducing bacteria (SRB) consortium. The SRB consortium used in this study was cultivated from a sour oil well in Louisiana, USA. 16S rRNA gene sequence analysis indicated that the mixed bacterial consortium contained three phylotypes: members of Proteobacteria ( Desulfomicrobium sp.), Firmicutes ( Clostridium sp.), and Bacteroidetes ( Anaerophaga sp.). The biofilm and the pits that developed with time were characterized using field emission scanning electron microscopy (FE-SEM). In addition, electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) and open circuit potential (OCP) were used to analyze the corrosion behavior. Through circuit modeling, EIS results were used to interpret the physicoelectric interactions between the electrode, biofilm and solution interfaces. The results confirmed that extensive localized corrosion activity of SRB is due to a formed biofilm in conjunction with a porous iron sulfide layer on the metal surface. X-ray diffraction (XRD) revealed semiconductive corrosion products predominantly composed of a mixture of siderite (FeCO3), iron sulfide (Fe x S y ), and iron (III) oxide-hydroxide (FeOOH) constituents in the corrosion products for the system exposed to the SRB consortium.

AlAbbas, Faisal M.; Williamson, Charles; Bhola, Shaily M.; Spear, John R.; Olson, David L.; Mishra, Brajendra; Kakpovbia, Anthony E.

2013-11-01

253

SYMBIODINIUM ISOLATES FROM STONY CORAL: ISOLATION, GROWTH CHARACTERISTICS AND EFFECTS OF UV IRRADIATION  

EPA Science Inventory

Symbiodinium spp. Isolates from Stony Coral: Isolation, Growth Characteristics and Effects of UV Irradiation (Abstract). J. Phycol. 37(3):42-43. Symbiodinium species were isolated from Montipora capitata, Acropora palmata and two field samples of Porites porites. Cultures ...

254

Isolation of haemolytic bacilli from field-collected Culicoides oxystoma and Culicoides peregrinus: potential vectors of bluetongue virus in West Bengal, India.  

PubMed

Two haemolytic bacterial strains of Bacillus pumilus (CU1A, CU1B) and one blood-utilizing strain of Bacillus licheniformis (CU2B) were isolated from relatively low numbers of field-collected females of Culicoides oxystoma and Culicoides peregrinus (Diptera: Ceratopogonidae). A total of 36 females, including 18 of each of C.?oxystoma and C.?peregrinus (consisting of one and a pool of eight blood-engorged specimens, and one and a pool of eight non-engorged specimens for each species), were tested. In C.?oxystoma, all three strains of bacteria were isolated from the one non-engorged, the pool of non-engorged and the pool of blood-engorged females tested, but CU1A and CU2B were not found in the one blood-engorged female tested. In C.?peregrinus, all three strains were present in the pool of blood-engorged females. However, the strain CU2B was not found in the pool of non-engorged females. In the one blood-engorged and one non-engorged female tested, CU1A and CU2B were detected. The bacterial strains were identified based on Gram staining, enzyme activity (amylase and protease) and alignment of the 16S rRNA partial gene sequence to that available in the National Center for Biotechnology Information (NCBI) database GenBank. The functional role and significance of these haemolytic and blood-digesting bacteria within the genus Culicoides remain to be determined. PMID:25644315

Harsha, R; Pan, B; Ghosh, K; Mazumdar, A

2015-06-01

255

Isolation precautions  

MedlinePLUS

Isolation precautions create barriers between people and germs. These types of precautions help prevent the spread of ... who visits a hospital patient who has an isolation sign outside their door should stop at the ...

256

Genomic and microarray analysis of aromatics degradation in Geobacter metallireducens and comparison to a Geobacter isolate from a contaminated field site  

PubMed Central

Background Groundwater and subsurface environments contaminated with aromatic compounds can be remediated in situ by Geobacter species that couple oxidation of these compounds to reduction of Fe(III)-oxides. Geobacter metallireducens metabolizes many aromatic compounds, but the enzymes involved are not well known. Results The complete G. metallireducens genome contained a 300 kb island predicted to encode enzymes for the degradation of phenol, p-cresol, 4-hydroxybenzaldehyde, 4-hydroxybenzoate, benzyl alcohol, benzaldehyde, and benzoate. Toluene degradation genes were encoded in a separate region. None of these genes was found in closely related species that cannot degrade aromatic compounds. Abundant transposons and phage-like genes in the island suggest mobility, but nucleotide composition and lack of synteny with other species do not suggest a recent transfer. The inferred degradation pathways are similar to those in species that anaerobically oxidize aromatic compounds with nitrate as an electron acceptor. In these pathways the aromatic compounds are converted to benzoyl-CoA and then to 3-hydroxypimelyl-CoA. However, in G. metallireducens there were no genes for the energetically-expensive dearomatizing enzyme. Whole-genome changes in transcript levels were identified in cells oxidizing benzoate. These supported the predicted pathway, identified induced fatty-acid oxidation genes, and identified an apparent shift in the TCA cycle to a putative ATP-yielding succinyl-CoA synthase. Paralogs to several genes in the pathway were also induced, as were several putative molybdo-proteins. Comparison of the aromatics degradation pathway genes to the genome of an isolate from a contaminated field site showed very similar content, and suggested this strain degrades many of the same compounds. This strain also lacked a classical dearomatizing enzyme, but contained two copies of an eight-gene cluster encoding redox proteins that was 30-fold induced during benzoate oxidation. Conclusion G. metallireducens appears to convert aromatic compounds to benzoyl-CoA, then to acetyl-CoA via fatty acid oxidation, and then to carbon dioxide via the TCA cycle. The enzyme responsible for dearomatizing the aromatic ring may be novel, and energetic investments at this step may be offset by a change in succinate metabolism. Analysis of a field isolate suggests that the pathways inferred for G. metallireducens may be applicable to modeling in situ bioremediation. PMID:17578578

Butler, Jessica E; He, Qiang; Nevin, Kelly P; He, Zhili; Zhou, Jizhong; Lovley, Derek R

2007-01-01

257

Colonization of Bordetella pertussis Clinical Isolates that Differ by Pulsed Field Gel Electrophoresis Types in the Lungs of Naïve Mice or Mice Immunized with the Whole-Cell Pertussis Vaccine Used in Poland.  

PubMed

The goal of our study was to compare the elimination of Bordetella pertussis clinical isolates that differ according to pulsed field gel electrophoresis (PFGE), serotypes and genes encoding virulence factors from the lungs of naïve mice or mice immunized with commercial diphtheria-tetanus-whole-cell pertussis vaccine used in Poland. When a mixture of four isolates, given in equal proportions and harboring different PFGE profiles, serotypes, and alleles encoding virulence factors, was used to infect non-immunized mice, a single isolate, characterized by PFGE type IV?, Fim2 phenotype and ptxA1-prn2-tcfA2-fim2-1-ptxP1-ptxC1-fim3-1 alleles, was found to be significantly predominant compared to the others. This PFGE profile is commonly found in B. pertussis isolates circulating in some European countries since the late 1990s, confirming its high fitness. The Polish commercial whole-cell pertussis vaccine induced an immunity effective at eliminating the B. pertussis isolates from the lungs. However, the elimination of the isolate harboring PFGE type C profile, Fim2,3 phenotype and ptxA1-prn1-tcfA2-fim2-1-ptxP1-ptxC1-fim3-1 alleles was delayed as compared to the others, suggesting phenotypic differences with the other isolates and vaccine strains. Nevertheless, the same isolate, when challenged into mice in the defined mixture of strains, lost the competition with the others, as measured by lung colonization efficiency. This PFGE profile represents 15 % of the isolates circulating in Poland between 2001 and 2012. PMID:25297678

Polak, Maciej; Zawadka, Monika; Mosiej, Ewa; Rabczenko, Daniel; Augustynowicz, Ewa; Guiso, Nicole; Luty?ska, Anna

2015-04-01

258

Comparative purification and characterization of two distinct extracellular monocrotophos hydrolases secreted by Penicillium aculeatum and Fusarium pallidoroseum isolated from agricultural fields.  

PubMed

The present study aimed at a comparative characterization of two distinct extracellular monocrotophos hydrolases, from Penicillium aculeatum ITCC 7980.10 (M3) and Fusarium pallidoroseum ITCC 7785.10 (M4), isolated from agricultural fields. The MCP hydrolases were purified by Sephadex G-100 column and DEAE-Sepharose CL-6B ion-exchange column followed by SDS-PAGE analysis, which showed the presence of two hydrolases, of 33 and 67 kDa respectively. Both enzymes were most active at alkaline pH and were stable over a wide range of temperatures (60-70 °C). Between the strains, the MCP hydrolases from M3 were 2-fold more active than that from M4. Enzyme kinetic studies showed lowest Km (33.52 mM) and highest Vmax (5.18 U/mg protein) for OPH67 of M3 in comparison to the Km and Vmax of the other hydrolases purified from M3 and M4, suggesting that M3 OPH67 was the most efficient MCP hydrolase. To the best of our knowledge, this is the first report of the purification of two distinct extracellular thermostable MCP hydrolases from fungal strains Penicillium aculeatum ITCC 7980.10 and Fusarium pallidoroseum ITCC 7785.10. Owing to its potential MCP hydrolyzing activity, M3 OPH67 can perhaps used directly or in the encapsulated form for remediation of MCP contaminated sites. PMID:23666511

Jain, Rachna; Garg, Veena; Dangwal, Koushalya; Lily, Madhuri Kaushish

2013-01-01

259

The rph1 Gene Is a Common Contributor to the Evolution of Phosphine Resistance in Independent Field Isolates of Rhyzopertha Dominica  

PubMed Central

Phosphine is the only economically viable fumigant for routine control of insect pests of stored food products, but its continued use is now threatened by the world-wide emergence of high-level resistance in key pest species. Phosphine has a unique mode of action relative to well-characterised contact pesticides. Similarly, the selective pressures that lead to resistance against field sprays differ dramatically from those encountered during fumigation. The consequences of these differences have not been investigated adequately. We determine the genetic basis of phosphine resistance in Rhyzopertha dominica strains collected from New South Wales and South Australia and compare this with resistance in a previously characterised strain from Queensland. The resistance levels range from 225 and 100 times the baseline response of a sensitive reference strain. Moreover, molecular and phenotypic data indicate that high-level resistance was derived independently in each of the three widely separated geographical regions. Despite the independent origins, resistance was due to two interacting genes in each instance. Furthermore, complementation analysis reveals that all three strains contain an incompletely recessive resistance allele of the autosomal rph1 resistance gene. This is particularly noteworthy as a resistance allele at rph1 was previously proposed to be a necessary first step in the evolution of high-level resistance. Despite the capacity of phosphine to disrupt a wide range of enzymes and biological processes, it is remarkable that the initial step in the selection of resistance is so similar in isolated outbreaks. PMID:22363668

Mau, Yosep S.; Collins, Patrick J.; Daglish, Gregory J.; Nayak, Manoj K.; Pavic, Hervoika; Ebert, Paul R.

2012-01-01

260

The effect of 5-HT and electrical field stimulation on the contractility of the whole isolated urinary bladder of Suncus murinus.  

PubMed

The present study used the whole isolated urinary bladder of Suncus murinus, to investigate the effect of exogenously added serotonin (5-HT) and electrical field stimulation (EFS) in the absence and presence of methysergide, a 5-HT1/2/7 receptor antagonist or the selective 5-HT7 receptor antagonist, SB269970. Further experiments investigated the involvement of potassium channel, cholinergic and purinergic systems in mediating the contractile response to EFS. Pre-treatment with methysergide reduced and increased the contractile responses to 5-HT and EFS, respectively. Pre-treatment with SB269970 increased the responses to 5-HT without modifying the EFS-induced contractions. EFS-induced contractions were not modified by pre-treatment with atropine (10?M), ?-?-methylene ATP or glibenclamide. EFS-induced contractions were attenuated by cromakalim (10µM) or atropine (0.1 µM). In conclusion, the 5-HT2 receptors are likely to play a role in mediating the contractile response to 5-HT in detrusor muscle. Furthermore, EFS-induced contractions are mediated through cholinergic and an unknown neurotransmitter which is modulated by K(ATP) channels in the detrusor muscle of Suncus murinus. PMID:24513135

Javid, Farideh A; Palea, Stefano

2014-01-15

261

Genetic diversity and effect of temperature and pH on the growth of Macrophomina phaseolina isolates from sunflower fields in Hungary  

Microsoft Academic Search

The effects of temperature and pH on the growth of 45 Hungarian Macrophomina phaseolina isolates from different locations and hosts were compared on the basis of their genetic diversity. One Spanish and two Serbian\\u000a isolates were also included in the experiment. The most favourable temperature regimes for the development of the isolates\\u000a ranged between 25 and 35°C. The optimal pH

Izabella Csöndes; András Cseh; János Taller; Péter Poczai

262

WIPP site and vicinity geological field trip. A report of a field trip to the proposed Waste Isolation Pilot Plant project in Southeastern New Mexico, June 16 to 18, 1980  

SciTech Connect

The Environmental Evaluation Group is conducting an assessment of the radiological health risks to people from the Waste Isolation Pilot Plant. As a part of this work, EEG is making an effort to improve the understanding of those geological issues concerning the WIPP site which may affect the radiological consequences of the proposed repository. One of the important geological issues to be resolved is the timing and the nature of the dissolution processes which may have affected the WIPP site. EEG organized a two-day conference of geological scientists, on January 17-18, 1980. On the basis of the January conference and the June field trip, EEG has formed the following conclusions: (1) it has not been clearly established that the site or the surrounding area has been attacked by deep dissolution to render it unsuitable for the nuclear waste pilot repository; (2) the existence of an isolated breccia pipe at the site unaccompanied by a deep dissolution wedge, is a very remote possibility; (3) more specific information about the origin and the nature of the brine reservoirs is needed. An important question that should be resolved is whether each encounter with artesian brine represents a separate pocket or whether these occurrences are interconnected; (4) Anderson has postulated a major tectonic fault or a fracture system at the Basin margin along the San Simon Swale; (5) the area in the northern part of the WIPP site, identified from geophysical and bore hole data as the disturbed zone, should be further investigated to cleary understand the nature and significance of this structural anomaly; and (6) a major drawback encountered during the discussions of geological issues related to the WIPP site is the absence of published material that brings together all the known information related to a particular issue.

Chaturvedi, L

1980-10-01

263

Analysis of genetic and molecular identity among field isolates of the rice blast fungus with an international differential system, rep-PCR and DNA sequencing  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Pi-ta gene deployed in the Southern US rice germplasm is effective in preventing the infection by strains of Magnaporthe oryzae isolates that carry the avirulence gene AVR-Pita1. In the present study, a total of 169 isolates from rice (Oryza sativa) cultivars, with and without Pi-ta, were analyz...

264

Genetic characterization of porcine epidemic diarrhea virus in Korea from 1998 to 2013.  

PubMed

The number of porcine epidemic diarrhea (PED) cases has increased over the past 20 years in Korea, with a major outbreak in 2013. A total of 27 Korean strains from 1998 to 2013 were analyzed (excluding the noncoding regions) and divided into two groups for comparison of the spike (S), ORF3, envelope (E), membrane (M), and nucleocapsid (N) genes with those of reference strains, vaccine strains, and previously identified strains based on phylogenetic analysis. Analysis of the selection patterns of PEDV isolated in Korea indicated positive selection of nine nonsynonymous sites in the S and N proteins and negative selection at 97 sites for all of the proteins. Interestingly, eight nonsynonymous mutations in S showed no significant pattern change over the 15-year period, and one of eight mutation sites was found only in IC05TK, GN05DJ, and KNU0802 in the epidemic years 2005 and 2008. These eight mutations were also present during the epidemic years in China. Furthermore, of the signs of positive selection in the S protein, the conservative substitutions were more frequent than radical substitutions in PEDVs, suggesting that the evolution of Korean strains has been slow. Serological cross-reactivity was detected between three field PEDVs and two vaccine strains, with different serum neutralization titers. In conclusion, although Korean PEDVs have been evolving slowly, their diverse antigenicity and genetics imply that multilateral efforts to prevent future PED outbreaks are required. PMID:25666198

Kim, Seong-Hee; Lee, Jung-Min; Jung, Jongsun; Kim, In-Joong; Hyun, Bang-Hun; Kim, Hyun-Il; Park, Choi-Kyu; Oem, Jae-Ku; Kim, Yeon-Hee; Lee, Myoung-Heon; Lee, Kyoung-Ki

2015-04-01

265

Evaluation of allelic forms of the erythrocyte binding antigen 175 (EBA-175) in Plasmodium falciparum field isolates from Brazilian endemic area  

PubMed Central

Background The Plasmodium falciparum Erythrocyte Binding Antigen-175 (EBA-175) is an antigen considered to be one of the leading malaria vaccine candidates. EBA-175 mediates sialic acid-dependent binding to glycophorin A on the erythrocytes playing a crucial role during invasion of the P. falciparum in the host cell. Dimorphic allele segments, termed C-fragment and F-fragment, have been found in high endemicity malaria areas and associations between the dimorphism and severe malaria have been described. In this study, the genetic dimorphism of EBA-175 was evaluated in P. falciparum field isolates from Brazilian malaria endemic area. Methods The study was carried out in rural villages situated near Porto Velho, Rondonia State in the Brazilian Amazon in three time points between 1993 and 2008. The allelic dimorphism of the EBA-175 was analysed by Nested PCR. Results The classical allelic dimorphism of the EBA-175 was identified in the studied area. Overall, C-fragment was amplified in a higher frequency than F-fragment. The same was observed in the three time points where C-fragment was observed in a higher frequency than F-fragment. Single infections (one fragment amplified) were more frequent than mixed infection (two fragments amplified). Conclusions These findings confirm the dimorphism of EBA175, since only the two types of fragments were amplified, C-fragment and F-fragment. Also, the results show the remarkable predominance of CAMP allele in the studied area. The comparative analysis in three time points indicates that the allelic dimorphism of the EBA-175 is stable over time. PMID:21615944

2011-01-01

266

Rapid real-time PCR methods to distinguish Salmonella Enteritidis wildtype field isolates from vaccine strains Salmovac SE/Gallivac SE and AviPro SALMONELLA VAC E.  

PubMed

Salmonella enterica serovar Enteritidis is a major non-typhoid Salmonella serovar causing human salmonellosis mainly associated with the consumption of poultry and products thereof. To reduce infections in poultry, S. Enteritidis live vaccine strains AviPro SALMONELLA VAC E and Salmovac SE/Gallivac SE have been licensed and used in several countries worldwide. To definitively diagnose a S. Enteritidis contamination in vaccinated herds a reliable and fast method for the differentiation between vaccine and wildtype field isolates is required. In this study, we developed and validated real-time PCR (qPCR) assays to distinguish those variants genetically. Suitable target sequences were identified by whole genome sequencing (WGS) using the Illumina MiSeq system. SNP regions in kdpA and nhaA proved to be most useful for differentiation of AviPro SALMONELLA VAC E and Salmovac SE/Gallivac SE, respectively, from wildtype strains. For each vaccine strain one TaqMan-qPCR assay and one alternative approach using High Resolution Melting (HRM) analysis was designed. All 30 Salmovac SE and 7 AviPro SALMONELLA VAC E vaccine strain reisolates tested were correctly identified by both approaches (100% inclusivity). Furthermore, all 137 (TaqMan) and 97 (HRM) Salmonella non-vaccine and related Enterobacteriaceae strains tested were excluded (100% exclusivity). The analytical detection limits were determined to be approx. 10(2) genome copies/reaction for the TaqMan and 10(4) genome copies/reaction for the HRM approach. The real-time PCR assays proved to be a reliable and fast alternative to the cultural vaccine strain identification tests helping decision makers in control measurements to take action within a shorter period of time. PMID:25794902

Maurischat, Sven; Szabo, Istvan; Baumann, Beatrice; Malorny, Burkhard

2015-05-01

267

The role of nanominerals and mineral nanoparticles in the transport of toxic trace metals: Field-flow fractionation and analytical TEM analyses after nanoparticle isolation and density separation  

NASA Astrophysics Data System (ADS)

Nanominerals and mineral nanoparticles from a mining-contaminated river system were examined to determine their potential to co-transport toxic trace metals. A recent large-scale dam removal project on the Clark Fork River in western Montana (USA) has released reservoir and upstream sediments contaminated with toxic trace metals (Pb, As, Cu and Zn), which had accumulated there as a consequence of more than a century and a half of mining activity proximal to the river's headwaters near the cities of Butte and Anaconda. To isolate the high-density nanoparticle fractions from riverbed and bank sediments, a density separation with sodium polytungstate (2.8 g/cm3) was employed prior to a standard nanoparticle extraction procedure. The stable, dispersed nanoparticulate fraction was then analyzed by analytical transmission electron microscopy (aTEM) and flow field-flow fractionation (FlFFF) coupled to both multi-angle laser light scattering (MALLS) and high-resolution, inductively coupled plasma mass spectrometry (HR-ICPMS). FlFFF analysis revealed a size distribution in the nano range and that the elution profiles of the trace metals matched most closely to that for Fe and Ti. aTEM confirmed these results as the majority of the Fe and Ti oxides analyzed were associated with one or more of the trace metals of interest. The main mineral phases hosting trace metals are goethite, ferrihydrite and brookite. This demonstrates that they are likely playing a significant role in dictating the transport and distribution of trace metals in this river system, which could affect the bioavailability and toxicity of these metals.

Plathe, Kelly L.; von der Kammer, Frank; Hassellöv, Martin; Moore, Johnnie N.; Murayama, Mitsuhiro; Hofmann, Thilo; Hochella, Michael F.

2013-02-01

268

Identification and Characterization of a New Erythromycin Biosynthetic Gene Cluster in Actinopolyspora erythraea YIM90600, a Novel Erythronolide-Producing Halophilic Actinomycete Isolated from Salt Field  

PubMed Central

Erythromycins (Ers) are clinically potent macrolide antibiotics in treating pathogenic bacterial infections. Microorganisms capable of producing Ers, represented by Saccharopolyspora erythraea, are mainly soil-dwelling actinomycetes. So far, Actinopolyspora erythraea YIM90600, a halophilic actinomycete isolated from Baicheng salt field, is the only known Er-producing extremophile. In this study, we have reported the draft genome sequence of Ac. erythraea YIM90600, genome mining of which has revealed a new Er biosynthetic gene cluster encoding several novel Er metabolites. This Er gene cluster shares high identity and similarity with the one of Sa. erythraea NRRL2338, except for two absent genes, eryBI and eryG. By correlating genotype and chemotype, the biosynthetic pathways of 3?-demethyl-erythromycin C, erythronolide H (EH) and erythronolide I have been proposed. The formation of EH is supposed to be sequentially biosynthesized via C-6/C-18 epoxidation and C-14 hydroxylation from 6-deoxyerythronolide B. Although an in vitro enzymatic activity assay has provided limited evidence for the involvement of the cytochrome P450 oxidase EryFAc (derived from Ac. erythraea YIM90600) in the catalysis of a two-step oxidation, resulting in an epoxy moiety, the attempt to construct an EH-producing Sa. erythraea mutant via gene complementation was not successful. Characterization of EryKAc (derived from Ac. erythraea YIM90600) in vitro has confirmed its unique role as a C-12 hydroxylase, rather than a C-14 hydroxylase of the erythronolide. Genomic characterization of the halophile Ac. erythraea YIM90600 will assist us to explore the great potential of extremophiles, and promote the understanding of EH formation, which will shed new insights into the biosynthesis of Er metabolites. PMID:25250723

Chen, Dandan; Feng, Junyin; Huang, Lei; Zhang, Qinglin; Wu, Jiequn; Zhu, Xiangcheng; Duan, Yanwen; Xu, Zhinan

2014-01-01

269

Thiofractor thiocaminus gen. nov., sp. nov., a novel hydrogen-oxidizing, sulfur-reducing epsilonproteobacterium isolated from a deep-sea hydrothermal vent chimney in the Nikko Seamount field of the northern Mariana Arc.  

PubMed

A novel chemolithoautotrophic hydrogen-oxidizing and sulfur-reducing bacterium, strain 496Chim(T), was isolated from a deep-sea hydrothermal vent chimney collected from the hydrothermal field at the summit of Nikko Seamount field, in the Mariana Arc. Cells were rods or curved rods, motile by means of a single polar flagellum. Growth was observed between 15 and 45 °C (optimum 37 °C; doubling time, 2.1 h) and between pH 5.3 and 8.0 (optimum pH 6.0). The isolate was a strictly anaerobic, obligate chemolithoautotroph capable of growth using molecular hydrogen as the sole energy source, carbon dioxide as the sole carbon source, ammonium or nitrate as the sole nitrogen source, and elemental sulfur as the electron acceptor. The G+C content of genomic DNA was 35 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the new isolate belonged to the class Epsilonproteobacteria, but the isolate was distantly related to the previously described Epsilonproteobacteria species potentially at the genus level (<90 %). On the basis of its physiological and molecular characteristics, strain 496Chim(T) (=DSM 22050(?) = JCM 15747(?) = NBRC 105224(?)) represents the sole species of a new genus, Thiofractor, for which the name Thiofractor thiocaminus is proposed. PMID:22526267

Makita, Hiroko; Nakagawa, Satoshi; Miyazaki, Masayuki; Nakamura, Ko-ichi; Inagaki, Fumio; Takai, Ken

2012-09-01

270

Isolated Malignant Melanoma Metastasis to the Pancreas  

PubMed Central

Summary: Malignant melanomas rarely develop isolated pancreatic metastases. We describe a unique patient who is still alive 22 years following an isolated pancreatic melanoma metastasis, and we review the sparse literature in the field. PMID:25289269

Krag, Christen; Geertsen, Poul; Jakobsen, Linda P.

2013-01-01

271

A second RGD motif in the 1D capsid protein of a SAT1 type foot-and-mouth disease virus field isolate is not essential for attachment to target cells  

Microsoft Academic Search

The amino acid sequence motif Arg-Gly-Asp (RGD), located in the surface-exposed ?G-?H loop of the 1D protein of different serotypes and subtypes of foot-and-mouth disease virus (FMDV), is highly conserved and participates in binding of FMDV to susceptible cells. Previous sequence analyses of the 1D-encoding region of a FMDV serotype SAT1 field isolate from Namibia (NAM\\/307\\/98) indicated the presence of

P. Storey; J. Theron; F. F. Maree; H. G. O’Neill

2007-01-01

272

Comparative Studies of Mutations in Animal Isolates and Experimental In Vitro and In Vivo-Selected Mutants of Salmonella spp. Suggest a Counterselection of Highly Fluoroquinolone-Resistant Strains in the Field  

Microsoft Academic Search

The occurrence of mutations in the genes coding for gyrase (gyrA and gyrB) and topoisomerase IV (parE and parC )o fSalmonella typhimurium experimental mutants selected in vitro and in vivo and of 138 nalidixic acid-resistant Salmonella field isolates was investigated. The sequencing of the quinolone resistance-determin- ing region of these genes in highly fluoroquinolone-resistant mutants (MICs of 4 to 16

ETIENNE GIRAUD; ANNE BRISABOIS; JEAN-LOUIS MARTEL; ELISABETH CHASLUS-DANCLA

1999-01-01

273

Isolated Aortitis  

MedlinePLUS

... are forms of large vessel vasculitis, most commonly giant cell arteritis and Takayasu arteritis. Other autoimmune diseases ... cases are due to a rheumatic cause like giant cell arteritis and Takayasu arteritis. Who gets Isolated ...

274

Isolating Triggered Star Formation  

E-print Network

Galaxy pairs provide a potentially powerful means of studying triggered star formation from galaxy interactions. We use a large cosmological N-body simulation coupled with a well-tested semi-analytic substructure model to demonstrate that the majority of galaxies in close pairs reside within cluster or group-size halos and therefore represent a biased population, poorly suited for direct comparison to ``field'' galaxies. Thus, the frequent observation that some types of galaxies in pairs have redder colors than ``field'' galaxies is primarily a selection effect. We select galaxy pairs that are isolated in their dark matter halos with respect to other massive subhalos (N=2 halos) and a control sample of isolated galaxies (N=1 halos) for comparison. We then apply these selection criteria to a volume-limited subset of the 2dF Galaxy Redshift Survey with M_Bj isolated 50 (30) kpc/h pairs exhibit star formation that is boosted by a factor of >~ 5 above their average past value, while only 10% of isolated galaxies in the control sample show this level of enhancement. Thus, 14% (20 %) of the galaxies in these close pairs show clear triggered star formation. The isolation criteria we develop provide a means to constrain star formation and feedback prescriptions in hydrodynamic simulations and a very general method of understanding the importance of triggered star formation in a cosmological context. (Abridged.)

Elizabeth J. Barton; Jacob A. Arnold; Andrew R. Zentner; James S. Bullock; Risa H. Wechsler

2007-08-21

275

Pathogenicity of entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana (Hypocreales: Clavicipitaceae) isolates to the adult pea leafminer (Diptera: Agromyzidae) and prospects of an autoinoculation device for infection in the field.  

PubMed

Seventeen isolates of Metarhizium anisopliae (Metschnikoff) Sorokin and three isolates of Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) were evaluated for their pathogenicity to the adult pea leafminer, Liriomyza huidobrensis (Blanchard) (Diptera: Agromyzidae), in the laboratory. Flies were contaminated with dry conidia through a velvet material wrapped around the inner side of a cylindrical plastic tube. All the isolates were pathogenic to the pea leafminer, causing mortality between 40 and 100% at 5 d after exposure. The lethal time for 50% mortality (LT(50)) ranged from 2.6 to 5.4 d, whereas the LT(90) values varied between 3.2 and 9.1 d depending on the isolate. An autoinoculation device was evaluated in cage field experiments using only one of the virulent isolates, M. anisopliae ICIPE 20. The device was loaded with 2-3 g of dry conidia. Mortality of up to 100% was observed in flies captured from fungus-treated cages held under laboratory conditions. The average number of spores picked up by a single fly visiting the device increased with days after inoculation. One day after the inoculation, adults picked up an average of 4.1 +/- 0.7 x 10(5) conidia and 39.6 +/- 4.0 x 10(5) conidia 5 d after inoculation. Depending on the sampling date, the LT(50) varied between 1.8 and 3.4 d. Results indicate that some isolates of B. bassiana and M. anisopliae are highly pathogenic to L. huidobrensis, suggesting a potential for their use in the control of this pest. They also suggest the possibility of L. huidobrensis suppression with fungi using an autoinoculation device. PMID:20388276

Migiro, L N; Maniania, N K; Chabi-Olaye, A; Vandenberg, J

2010-04-01

276

Delegated isolation  

Microsoft Academic Search

Isolation---the property that a task can access shared data without interference from other tasks---is one of the most basic concerns in parallel programming. In this paper, we present Aida, a new model of isolated execution for parallel programs that perform frequent, irregular accesses to pointer-based shared data structures. The three primary benefits of Aida are dynamism, safety and liveness guarantees,

Roberto Lublinerman; Jisheng Zhao; Zoran Budimli?; Swarat Chaudhuri; Vivek Sarkar

2011-01-01

277

Comparative Studies of Mutations in Animal Isolates and Experimental In Vitro- and In Vivo-Selected Mutants of Salmonella spp. Suggest a Counterselection of Highly Fluoroquinolone-Resistant Strains in the Field  

PubMed Central

The occurrence of mutations in the genes coding for gyrase (gyrA and gyrB) and topoisomerase IV (parE and parC) of Salmonella typhimurium experimental mutants selected in vitro and in vivo and of 138 nalidixic acid-resistant Salmonella field isolates was investigated. The sequencing of the quinolone resistance-determining region of these genes in highly fluoroquinolone-resistant mutants (MICs of 4 to 16 ?g/ml) revealed the presence of gyrA mutations at codons corresponding to Gly-81 or Ser-83, some of which were associated with a mutation at Asp-87. No mutations were found in the gyrB, parC, and parE genes. An assay combining allele-specific PCR and restriction fragment length polymorphism was developed to rapidly screen mutations at codons 81, 83, and 87 of gyrA. The MICs of ciprofloxacin for the field isolates reached only 2 ?g/ml, versus 16 ?g/ml for some in vitro-selected mutants. The field isolates, like the mutants selected in vivo, had only a single gyrA mutation at codon 83 or 87. Single gyrA mutations were also found in highly resistant in vitro-selected mutants (MIC of ciprofloxacin, 8 ?g/ml), which indicates that mechanisms other than the unique modification of the intracellular targets could participate in fluoroquinolone resistance in Salmonella spp. A comparison of experimental mutants selected in vitro, field strains, and mutants selected in vivo suggests that highly fluoroquinolone-resistant strains are counterselected in field conditions in the absence of selective pressure. PMID:10471553

Giraud, Etienne; Brisabois, Anne; Martel, Jean-Louis; Chaslus-Dancla, Elisabeth

1999-01-01

278

Fabrication of high-k/metal-gate MoS2 field-effect transistor by device isolation process utilizing Ar-plasma etching  

NASA Astrophysics Data System (ADS)

We investigated a device isolation process for MoS2-based devices and fabricated high-k/metal-gate MoS2 MOSFETs. An Ar-ion etching process was utilized for the device isolation process. It circumvents damage in the device channel, as confirmed by Raman spectroscopy. A top-gate MoS2 MOSFET was fabricated with a HfO2 thin film 16 nm thick as the gate insulator. Utilizing capacitance–voltage (C–V) measurements, the capacitance equivalent thickness (CET) was estimated to be 5.36 nm, which indicates that a gate stack with the sufficiently thin insulator was successfully realized. The device exhibited a mobility of 25.3 cm2/(V·s), a subthreshold swing (SS) of 86.0 mV/decade, and an ON/OFF ratio of 107. This satisfactory device performance demonstrates the feasibility of the proposed device isolation process.

Ninomiya, Naruki; Mori, Takahiro; Uchida, Noriyuki; Watanabe, Eiichiro; Tsuya, Daiju; Moriyama, Satoshi; Tanaka, Masatoshi; Ando, Atsushi

2015-04-01

279

A user friendly method to isolate and single spore the fungi Magnaporthe oryzae and Magnaporthe grisea obtained from diseased field samples  

Technology Transfer Automated Retrieval System (TEKTRAN)

The fungus Magnaporthe oryzae is the causal agent for a wide range of plant diseases including diseases of rice, wheat, rye grass, turfgrass and pearl millet. A simple robust procedure for fungal isolation is not publicly available. In the present study, a user friendly method was developed to iso...

280

Isolation, Pathogenicity and Safety of Curvularia eragrostidis Isolate QZ-2000 as a Bioherbicide Agent for Large Crabgrass (Digitaria sanguinalis)  

Microsoft Academic Search

A pathogen isolated from lesions on blighted leaves of crabgrass in three different locations of China was identified as Curvularia eragrostidis. Isolate QZ-2000 was the most virulent of six isolates tested. Experiments on morphology, pathogenicity, effect of environmental factors, and host-range of isolate QZ-2000 were conducted in the laboratory, greenhouse and field to assess the potential of this isolate as

Yunzhi Zhu; Sheng Qiang

2004-01-01

281

Signal Isolators  

NASA Astrophysics Data System (ADS)

The City of Dubuque, Iowa's new Water Division computer system was experiencing failures of the analog inputs ranging from signals out of tolerance by more than 30 percent to intermittent and sometimes complete loss of signals. The problem stemmed from a lack of signal isolation of the analog input cards, which made the inputs vulnerable to interference from storms and machinery. Electronic technician Bob Ervolino read an article in Tech Briefs describing an Ames Research Center solution to a similar problem. He studied the Technical Support Package and contacted the vendor; the information saved the Water Division more than 50 percent of the cost of commercial isolators.

1991-01-01

282

Sequence variation of the glycoprotein gene identifies three distinct lineages within field isolates of viral haemorrhagic septicaemia virus, a fish rhabdovirus.  

PubMed

To evaluate the genetic diversity of viral haemorrhagic septicaemia virus (VHSV), the sequence of the glycoprotein genes (G) of 11 North American and European isolates were determined. Comparison with the G protein of representative members of the family Rhabdoviridae suggested that VHSV was a different virus species from infectious haemorrhagic necrosis virus (IHNV) and Hirame rhabdovirus (HIRRV). At a higher taxonomic level, VHSV, IHNV and HIRRV formed a group which was genetically closest to the genus Lyssavirus. Compared with each other, the G genes of VHSV displayed a dissimilar overall genetic diversity which correlated with differences in geographical origin. The multiple sequence alignment of the complete G protein, showed that the divergent positions were not uniformly distributed along the sequence. A central region (amino acid position 245-300) accumulated substitutions and appeared to be highly variable. The genetic heterogeneity within a single isolate was high, with an apparent internal mutation frequency of 1.2 x 10(-3) per nucleotide site, attesting the quasispecies nature of the viral population. The phylogeny separated VHSV strains according to the major geographical area of isolation: genotype I for continental Europe, genotype II for the British Isles, and genotype III for North America. Isolates from continental Europe exhibited the highest genetic variability, with sub-groups correlated partially with the serological classification. Neither neutralizing polyclonal sera, nor monoclonal antibodies, were able to discriminate between the genotypes. The overall structure of the phylogenetic tree suggests that VHSV genetic diversity and evolution fit within the model of random change and positive selection operating on quasispecies. PMID:9367370

Benmansour, A; Basurco, B; Monnier, A F; Vende, P; Winton, J R; de Kinkelin, P

1997-11-01

283

Genetic diversity and effect of temperature and pH on the growth of Macrophomina phaseolina isolates from sunflower fields in Hungary.  

PubMed

The effects of temperature and pH on the growth of 45 Hungarian Macrophomina phaseolina isolates from different locations and hosts were compared on the basis of their genetic diversity. One Spanish and two Serbian isolates were also included in the experiment. The most favourable temperature regimes for the development of the isolates ranged between 25 and 35 °C. The optimal pH for the pathogen varied between 4.0 and 6.0, but growth was observed on potato dextrose agar even at pH values of 3.0, 7.0 and 8.0. RAPD analysis with 13 different primer pairs generated 148 unambiguous bands. RFLP analysis involving 8 different restriction endonucleases was performed on a 1550 bp fragment of the rDNA region containing internal transcribed spacers (ITS1, ITS2), the 5.8S rDNA and part of the 25S rDNA. The greatest genetic distance values were obtained for three isolates, two from Hungary and one from Spain, which had similar values, but were quite distinct from all the others. A strong positive correlation was observed between the genetic distances and the growth parameters measured at various temperatures, and between the geographical data and the growth data sets at different pH values, but the correlation was less strong in the latter case. While Hungarian M. phaseolina populations are thought to reproduce clonally, the present results indicate the coexistence of different haplotypes in this area, and besides the geographical dominance of a given haplotype it was found that a closer genetic relationship might exist between spatially distinct haplotypes. PMID:21695429

Csöndes, Izabella; Cseh, András; Taller, János; Poczai, Péter

2012-03-01

284

Visible optical isolator using ZnSe  

NASA Technical Reports Server (NTRS)

A compact Faraday effect optical isolator was constructed for visible wavelengths and tested at 5145 A. The nonreciprocal element of the isolator was polycrystalline zinc selenide placed in the magnetic field of a permanent magnet. For 5145 A the isolator had a 2.06-dB insertion loss and a 25.5-dB isolation. Indices of refraction and Verdet constants were measured for zinc selenide in the wavelength region from 4700 to 6300 A.

Wunderlich, J. A.; Deshazer, L. G.

1977-01-01

285

Determination of selected pesticides in water samples adjacent to agricultural fields and removal of organophosphorus insecticide chlorpyrifos using soil bacterial isolates  

NASA Astrophysics Data System (ADS)

The use of pesticide for crops leads to serious environmental pollution, therefore, it is essential to monitor and develop approaches to remove pesticide from contaminated environment. In this study, water samples were collected to monitor pesticide residues, and degradation of chlorpyrifos was also performed using soil bacteria. Identification of pesticide residues and determination of their levels were performed by high-performance liquid chromatography with photodiode array detector. Among 12 samples, 10 samples were found contaminated with pesticides. Chlorpyrifos was detected in four tested samples and concentrations ranged from 3.27 to 9.31 ?g/l whereas fenitrothion ranging from (Below Detection Limit, <0.1 ?g/l) to 33.41 ?g/l in the tested samples. Parathion was found in two tested samples at the concentration of 0.73 and 6.23 ?g/l. None of the tested samples was found contaminated with Methoxychlor, DDT and Ethion. Three soil bacterial isolates, Pseudomonas peli BG1, Burkholderia caryophylli BG4 and Brevundimonas diminuta PD6 degraded chlorpyrifos completely in 8, 10 and 10 days, respectively, when 20 mg/l chlorpyrifos was supplied as sole source of carbon. Whereas, BG1, BG4 and PD6 took 14, 16 and 16 days, respectively, for complete removal of 50 mg/l chlorpyrifos. Chlorpyrifos degradation rates were found maximum by all three isolates at 2nd day of incubation for both tested concentrations. The results of the present study suggest the need for regular monitoring of pesticide residues in water, to protect the aquatic environment. Chlorpyrifos degrading bacterial isolates can be used to clean up environmental samples contaminated with the organophosphate pesticides.

Hossain, M. S.; Chowdhury, M. Alamgir Zaman; Pramanik, Md. Kamruzzaman; Rahman, M. A.; Fakhruddin, A. N. M.; Alam, M. Khorshed

2014-03-01

286

Molecular Genotyping of Shigella sonnei Strains Isolated From Children With Bloody Diarrhea Using Pulsed Field Gel Electrophoresis on the Total Genome and PCR-RFLP of IpaH and IpaBCD Genes  

PubMed Central

Background: Identification, understanding of antibiotic sensitivity patterns and molecular characterization of genetic elements of Shigella species are important because of both epidemiological and clinical indications in developing countries. Objectives: The aim of this study was to analyze molecular epidemiology of Shigella isolates recovered from children with diarrhea in Shiraz (Southern Iran), using IpaH and IpaBCD PCR-restriction fragment length polymorphism (RFLP), and to determine pulsed field gel electrophoresis (PFGE) patterns of total DNA of the S. sonnei isolates to find the clonality among these strains. Patients and Methods: A total of 82 clinical strains of Shigella spp., S. sonnei (n = 61), S. flexneri (n = 16), Shigella boydii (n = 3) and S. dysenteriae (n = 2) isolated from the stool samples of 719 patients, aged two months to 14 years, with positive occult blood (OB) test were characterized based on their IpaH and IpaBCD genes PCR-RFLP patterns. Genomic DNAs of S. sonnei strains were analyzed by PFGE. Results: All Shigella isolates were positive for both invasive genes and showed homogeneous profiles for such genes except for two S. sonnei strains, which had IpaH bands with different sizes and PCR-RFLP profiles. Forty palsotypes were determined among the 41 S. sonnei strains. Sample patterns were divided into two groups based on the drawn dendrogram with a similarity range of 70% to 100%. Conclusions: The results revealed that the strains under study could be epidemically related. It seems that an alternative subtyping method is needed to study the relationship among clinical S. sonnei strains and their transmission. Here, we reported for the first time, two strains of S. sonnei with a different PCR-RFLP pattern for IpaH gene.

Farshad, Shohreh; Ranjbar, Reza; Hosseini, Marziyeh

2014-01-01

287

Nonorthogonally magnetised permanent-magnet Faraday isolators  

SciTech Connect

This paper describes a novel configuration of permanent-magnet magnetic systems for high-power Faraday isolators that are used in high-power lasers. An increase in magnetic field is ensured by magnets with a magnetisation vector inclined to the isolator axis. Numerical simulation results agree well with experimentally determined magnetic field distributions. (quantum electronic devices)

Mironov, E A; Voitovich, A V; Palashov, O V [Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod (Russian Federation)

2011-01-31

288

Genetic polymorphisms in the glutamate-rich protein of Plasmodium falciparum field isolates from a malaria-endemic area of Brazil  

PubMed Central

The genetic diversity displayed by Plasmodium falciparum, the most deadly Plasmodium species, is a significant obstacle for effective malaria vaccine development. In this study, we identified genetic polymorphisms in P. falciparum glutamate-rich protein (GLURP), which is currently being tested in clinical trials as a malaria vaccine candidate, from isolates found circulating in the Brazilian Amazon at variable transmission levels. The study was performed using samples collected in 1993 and 2008 from rural villages situated near Porto Velho, in the state of Rondônia. DNA was extracted from 126 P. falciparum-positive thick blood smears using the phenol-chloroform method and subjected to a nested polymerase chain reaction protocol with specific primers against two immunodominant regions of GLURP, R0 and R2. Only one R0 fragment and four variants of the R2 fragment were detected. No differences were observed between the two time points with regard to the frequencies of the fragment variants. Mixed infections were uncommon. Our results demonstrate conservation of GLURP-R0 and limited polymorphic variation of GLURP-R2 in P. falciparum isolates from individuals living in Porto Velho. This is an important finding, as genetic polymorphisms in B and T-cell epitopes could have implications for the immunological properties of the antigen. PMID:23828006

Pratt-Riccio, Lilian Rose; Perce-da-Silva, Daiana de Souza; Lima-Junior, Josué da Costa; Theisen, Michael; Santos, Fátima; Daniel-Ribeiro, Cláudio Tadeu; de Oliveira-Ferreira, Joseli; Banic, Dalma Maria

2013-01-01

289

Candidate isolated neutron stars and other optically blank x-ray fields identified from the rosat all-sky and sloan digital sky surveys  

SciTech Connect

Only seven radio-quiet isolated neutron stars (INSs) emitting thermal X rays are known, a sample that has yet to definitively address such fundamental issues as the equation of state of degenerate neutron matter. We describe a selection algorithm based on a cross-correlation of the ROSAT All-Sky Survey (RASS) and the Sloan Digital Sky Survey (SDSS) that identifies X-ray error circles devoid of plausible optical counterparts to the SDSS g {approx} 22 magnitudes limit. We quantitatively characterize these error circles as optically blank; they may host INSs or other similarly exotic X-ray sources such as radio-quiet BL Lacs, obscured AGN, etc. Our search is an order of magnitude more selective than previous searches for optically blank RASS error circles, and excludes the 99.9% of error circles that contain more common X-ray-emitting subclasses. We find 11 candidates, nine of which are new. While our search is designed to find the best INS candidates and not to produce a complete list of INSs in the RASS, it is reassuring that our number of candidates is consistent with predictions from INS population models. Further X-ray observations will obtain pinpoint positions and determine whether these sources are entirely optically blank at g {approx} 22, supporting the presence of likely isolated neutron stars and perhaps enabling detailed follow-up studies of neutron star physics.

Agueros, Marcel A.; Anderson, Scott F.; /Washington U., Seattle, Astron. Dept.; Margon, Bruce; /Baltimore, Space Telescope Sci.; Haberl, Frank; Voges, Wolfgang; /Garching,; Annis, James; /Fermilab; Schneider, Donald P.; /Penn State U., Astron. Astrophys.; Brinkmann, Jonathan; /Apache Point Observ.

2005-11-01

290

Atomically thin nonreciprocal optical isolation  

PubMed Central

Optical isolators will play a critical role in next-generation photonic circuits, but their on-chip integration requires miniaturization with suitable nonreciprocal photonic materials. Here, we theoretically demonstrate the thinnest possible and polarization-selective nonreciprocal isolation for circularly polarized waves by using graphene monolayer under an external magnetic field. The underlying mechanism is that graphene electron velocity can be largely different for the incident wave propagating in opposite directions at cyclotron frequency, making graphene highly conductive and reflective in one propagation direction while transparent in the opposite propagation direction under an external magnetic field. When some practical loss is introduced, nonreciprocal isolation with graphene monolayer still possesses good performance in a broad bandwidth. Our work shows the first study on the extreme limit of thickness for optical isolation and provides theoretical guidance in future practical applications. PMID:24569672

Lin, Xiao; Wang, Zuojia; Gao, Fei; Zhang, Baile; Chen, Hongsheng

2014-01-01

291

Previous infection of sows with a "mild" strain of porcine epidemic diarrhea virus confers protection against infection with a "severe" strain.  

PubMed

Porcine epidemic diarrhea virus (PEDv) infected approximately 50% of the US swine breeding herds from July 2013 to July 2014 as estimated by the Swine Health Monitoring Project. In the absence of effective vaccines or standard control protocols, there is an urgent need for evidence of cross-protective immune countermeasures. Here, we evaluated the response of 3-day-old piglets born to sows exposed seven months earlier to a mild strain of PEDv to challenge with a virulent PEDv isolate. Piglet survival to one week of age was 100% compared to 67% in piglets born to sows not previously exposed, and morbidity was 43% compared to 100%, respectively. At necropsy at 7 days of age, the PEDv Ct value was 23.6 (range 16.6-30.6) in intestinal contents, compared to 17.2 (range 15.9-18.5) (p<0.06) in litters from sows with no previous exposure to PEDv. The findings indicated that durable lactogenic immunity was present in sows previously exposed to a mild strain of PEDv and this immunity induced cross-protection to representative virulent PEDv. Thus, a naturally attenuated form of PEDv provided significant passive immune protection for seven months against piglet challenge with virulent PEDv. PMID:25601801

Goede, Dane; Murtaugh, Michael P; Nerem, Joel; Yeske, Paul; Rossow, Kurt; Morrison, Robert

2015-03-23

292

Isolating Triggered Star Formation  

SciTech Connect

Galaxy pairs provide a potentially powerful means of studying triggered star formation from galaxy interactions. We use a large cosmological N-body simulation coupled with a well-tested semi-analytic substructure model to demonstrate that the majority of galaxies in close pairs reside within cluster or group-size halos and therefore represent a biased population, poorly suited for direct comparison to 'field' galaxies. Thus, the frequent observation that some types of galaxies in pairs have redder colors than 'field' galaxies is primarily a selection effect. We use our simulations to devise a means to select galaxy pairs that are isolated in their dark matter halos with respect to other massive subhalos (N= 2 halos) and to select a control sample of isolated galaxies (N= 1 halos) for comparison. We then apply these selection criteria to a volume-limited subset of the 2dF Galaxy Redshift Survey with M{sub B,j} {le} -19 and obtain the first clean measure of the typical fraction of galaxies affected by triggered star formation and the average elevation in the star formation rate. We find that 24% (30.5 %) of these L* and sub-L* galaxies in isolated 50 (30) h{sup -1} kpc pairs exhibit star formation that is boosted by a factor of {approx}> 5 above their average past value, while only 10% of isolated galaxies in the control sample show this level of enhancement. Thus, 14% (20 %) of the galaxies in these close pairs show clear triggered star formation. Our orbit models suggest that 12% (16%) of 50 (30) h{sup -1} kpc close pairs that are isolated according to our definition have had a close ({le} 30 h{sup -1} kpc) pass within the last Gyr. Thus, the data are broadly consistent with a scenario in which most or all close passes of isolated pairs result in triggered star formation. The isolation criteria we develop provide a means to constrain star formation and feedback prescriptions in hydrodynamic simulations and a very general method of understanding the importance of triggered star formation in a cosmological context.

Barton, Elizabeth J.; Arnold, Jacob A.; /UC, Irvine; Zentner, Andrew R.; /KICP, Chicago /Chicago U., EFI; Bullock, James S.; /UC, Irvine; Wechsler, Risa H.; /KIPAC, Menlo

2007-09-12

293

Cloning and Sequence Analysis of the Spike Gene of Porcine Epidemic Diarrhea Virus Chinju99  

Microsoft Academic Search

The spike (S) gene of the porcine epidemic diarrhea virus (PEDV) Chinju99 which was previously isolated in Chinju, Korea was cloned and sequenced to aid in the development of genetically engineered vaccines and diagnostic reagents against PEDV. The nucleotide sequence encoding the entire S gene open reading frame (ORF) of Chinju99 was 4152 bases long encoding 1383 amino acids. It

Sang-Geon Yeo; Mercedes Hernandez; Peter J. Krell; Éva É Nagy

2003-01-01

294

Cloning and sequence analysis of the Korean strain of spike gene of porcine epidemic diarrhea virus and expression of its neutralizing epitope in plants  

Microsoft Academic Search

Porcine epidemic diarrhea virus (PEDV) causes acute diarrhea and dehydration in pigs and leads to death with a high mortality rate, which has been reported notably in Korea. The spike (S) gene of the PEDV isolated in Korea was cloned and sequenced. The nucleotide sequence encoding the entire S gene open reading frame of Korean strain was 4161 bases long

Tae-Jin Kang; Jo-Eun Seo; Dae-Hyuk Kim; Tae-Geum Kim; Yong-Suk Jang; Moon-Sik Yang

2005-01-01

295

Radioactive waste isolation in salt: geochemistry of brine in rock salt in temperature gradients and gamma-radiation fields - a selective annotated bibliography  

SciTech Connect

Evaluation of the extensive research concerning brine geochemistry and transport is critically important to successful exploitation of a salt formation for isolating high-level radioactive waste. This annotated bibliography has been compiled from documents considered to provide classic background material on the interactions between brine and rock salt, as well as the most important results from more recent research. Each summary elucidates the information or data most pertinent to situations encountered in siting, constructing, and operating a mined repository in salt for high-level radioactive waste. The research topics covered include the basic geology, depositional environment, mineralogy, and structure of evaporite and domal salts, as well as fluid inclusions, brine chemistry, thermal and gamma-radiation effects, radionuclide migration, and thermodynamic properties of salts and brines. 4 figs., 6 tabs.

Hull, A.B.; Williams, L.B.

1985-07-01

296

PedVed: Pseudo Euclidian Distances for Video Events Detection  

Microsoft Academic Search

This paper provides a new method that generates automatically pseudo Euclidian distances (PED) from the trigonometrically treatments of motion history blobs (MHB) obtained from motion history images (MHI) to extract efficient image features, which are pertinent to video events detection (VED). Given a point with its direction of motion where the point coincides the center of a circle. How far

Chabane Djeraba

2009-01-01

297

Optical Isolators With Transverse Magnets  

NASA Technical Reports Server (NTRS)

New design for isolator includes zigzag, forward-and-backward-pass beam path and use of transverse rather than longitudinal magnetic field. Design choices produce isolator with as large an aperture as desired using low-Verdet-constant glass rather than more expensive crystals. Uses commercially available permanent magnets in Faraday rotator. More compact and less expensive. Designed to transmit rectangular beam. Square cross section of beam extended to rectangular shape by increasing one dimension of glass without having to increase magnetic field. Potentially useful in laser systems involving slab lasers and amplifiers. Has applications to study of very-high-power lasers for fusion research.

Fan, Yuan X.; Byer, Robert L.

1991-01-01

298

Multiple strain infections and high genotypic diversity among Mycobacterium avium subsp. paratuberculosis field isolates from diseased wild and domestic ruminant species in the eastern Alpine region of Austria.  

PubMed

Johne's disease, or paratuberculosis, is a chronic fatal ruminant gastroenteritis caused by Mycobacterium avium subspecies paratuberculosis (MAP) whose foodborne zoonotic potential and association with Crohn's disease are still under debate. The disease is widespread but its epidemiology and epizootiology remains elusive. Wildlife is suspected to play a major role. After a surge in MAP seroprevalence in Austrian cattle, paratuberculosis was declared a notifiable disease in Austria in 2006. At the same time a rise in MAP cases in wild ruminant populations in the Austrian province of Styria was reported. All five autochthonous ruminants were affected. Genetic analysis of isolates, yielded numerous genotypes (>15) and several multiple strain infections (15%) across host species. Identical MIRU-VNTR profiles were identified in different species and sampling locations. On the other hand varying MIRU-VNTR profiles were revealed at the same location and in conspecifics. Our data, taken together with earlier epidemiological studies on MAP and other mycobacteria, raised concerns about the organisms' ecology. Constraints regarding in vitro culture of this highly fastidious organism potentially bias our current understanding of its epidemiology. We suggest that MAP infections could be polyclonal and question the informative value of genotyping a single MAP colony derived from a single specimen for epidemiological analysis of MAP. PMID:24270014

Gerritsmann, H; Stalder, G L; Spergser, J; Hoelzl, F; Deutz, A; Kuebber-Heiss, A; Walzer, C; Smith, S

2014-01-01

299

Characterization of Alkaliphilus hydrothermalis sp. nov., a novel alkaliphilic anaerobic bacterium, isolated from a carbonaceous chimney of the Prony hydrothermal field, New Caledonia.  

PubMed

A novel anaerobic, alkaliphilic, Gram-positive staining bacterium was isolated from a hydrothermal chimney in the Prony Bay, New Caledonia. This strain designated FatMR1(T) grew at temperatures from 20 to 55 °C (optimum 37 °C) and at pH between 7.5 and 10.5 (optimum 8.8-9). NaCl is not required for growth (optimum 0.2-0.5%), but is tolerated up to 3%. Sulfate, thiosulfate, elemental sulfur, sulfite, nitrate and nitrite are not used as terminal electron acceptors. Strain FatMR1(T) fermented pyruvate, yeast extract, peptone and biotrypcase and used fructose as the only sugar. The main fermentation products from fructose and proteinaceous compounds (e.g. peptone and biotrypcase) were acetate, H2 and CO2. Crotonate was disproportionated to acetate and butyrate. The predominant cellular fatty acids were C14:0 and C16:0. The G + C content of the genomic DNA was 37.1 mol%. On the basis of phylogenetic, genetic, and physiological properties, strain FatMR1(T) (=DSM 25890(T), =JCM 18390(T)) belonging to the phylum Firmicutes, class Clostridia, order Clostridiales, is proposed as a novel species of the genus Alkaliphilus, A. hydrothermalis sp. nov. PMID:25319677

Ben Aissa, Fatma; Postec, Anne; Erauso, Gaël; Payri, Claude; Pelletier, Bernard; Hamdi, Moktar; Fardeau, Marie-Laure; Ollivier, Bernard

2015-01-01

300

Occurrence of pfatpase6 Single Nucleotide Polymorphisms Associated with Artemisinin Resistance among Field Isolates of Plasmodium falciparum in North-Eastern Tanzania  

PubMed Central

We aimed to determine the current prevalence of four P. falciparum candidate artemisinin resistance biomarkers L263E, E431K, A623E, and S769N in the pfatpase6 gene in a high transmission area in Tanzania in a retrospective cross sectional study using 154 archived samples collected from three previous malaria studies in 2010, 2011 and 2013. Mutations in pfatpase6 gene were detected in parasite DNA isolated from Dried Blood Spots by using PCR-RFLP. We observed overall allelic frequencies for L263E, E431K, A623E, and S769N to be 5.8% (9/154), 16.2% (25/154), 0.0% (0/154), and 3.9% (6/154). The L263E mutation was not detected in 2010 but occurred at 3.9% and 2.6% in 2011 and 2013 respectively. The L263E mutation showed a significant change of frequency between 2010 and 2011, but not between 2011 and 2013 (P < 0.05). Frequency of E431K was highest of all without any clear trend whereas S769N increased from 2.2% in 2010 to 3.6% in 2011 and 5.1% in 2013. A623E mutation was not detected. The worrisome detection and the increase in the frequency of S769N and other mutations calls for urgent assessment of temporal changes of known artemisinin biomarkers in association with in vivo ACT efficacy. PMID:25685593

Chilongola, Jaffu; Ndaro, Arnold; Tarimo, Hipolite; Shedrack, Tamara; Barthazary, Sakurani; Kaaya, Robert; Masokoto, Alutu; Kajeguka, Debora; Kavishe, Reginald A.; Lusingu, John

2015-01-01

301

Drop-on-Demand Single Cell Isolation and Total RNA Analysis  

E-print Network

Technologies that rapidly isolate viable single cells from heterogeneous solutions have significantly contributed to the field of medical genomics. Challenges remain both to enable efficient extraction, isolation and ...

Moon, Sangjun

302

Mirincamycin, an old candidate for malaria combination treatment and prophylaxis in the 21st century: in vitro interaction profiles with potential partner drugs in continuous culture and field isolates  

PubMed Central

Background Spreading resistance of Plasmodium falciparum to existing drugs calls for the search for novel anti-malarial drugs and combinations for the treatment of falciparum malaria. Methods In vitro and ex vivo investigations were conducted with fresh P. falciparum field isolates and culture-adapted P. falciparum clones to evaluate the anti-malarial potential of mirincamycin, a lincosamide, alone and in combination with tafenoquine (TQ), dihydroartemisinin (DHA), and chloroquine (CQ). All samples were tested in a histidine-rich protein 2 (HRP2) drug susceptibility assay. Results Interaction analysis showed additive to synergistic interaction profiles with these potential partner drugs, with an overall geometric mean fractional inhibitory concentration at 50% inhibition (FIC50) of 0.78, 0.80 and 0.80 for mirincamycin with TQ, DHA, and CQ, respectively. Antagonism was not found in any of the tested field isolates or clones. The strongest tendency toward synergy (i.e. the lowest FIC) was seen with a combination ratio of 1:0.27 to 1:7.2 (mean 1:2.7) for the combination with tafenoquine. The optimal combination ratios for DHA and CQ were 1:444.4 to 1:36,000 (mean 1:10,755.5) and 1:2.7 to 1:216 (mean 1:64.5), respectively. No evidence of an activity correlation (i.e. potential cross-resistance) with DHA, mefloquine, quinine or chloroquine was seen whereas a significant correlation with the activity of clindamycin and azithromycin was detected. Conclusions Mirincamycin combinations may be promising candidates for further clinical investigations in the therapy and prophylaxis of multidrug-resistant falciparum malaria or in combination with 4 or 8-aminoquinolines for the treatment and relapse prevention of vivax malaria. PMID:24916383

2014-01-01

303

Ex vivo anti-malarial drugs sensitivity profile of Plasmodium falciparum field isolates from Burkina Faso five years after the national policy change  

PubMed Central

Background The recent reports on the decreasing susceptibility of Plasmodium falciparum to artemisinin derivatives along the Thailand and Myanmar border are worrying. Indeed it may spread to India and then Africa, repeating the same pattern observed for chloroquine resistance. Therefore, it is essential to start monitoring P. falciparum sensitivity to artemisinin derivatives and its partner drugs in Africa. Efficacy of AL and ASAQ were tested by carrying out an in vivo drug efficacy test, with an ex vivo study against six anti-malarial drugs nested into it. Results of the latter are reported here. Methods Plasmodium falciparum ex-vivo susceptibility to chloroquine (CQ), quinine (Q), lumefantrine (Lum), monodesethylamodiaquine (MDA), piperaquine (PPQ) and dihydroartemisinin (DHA) was investigated in children (6 months – 15 years) with a parasitaemia of at least ?4,000/?l. The modified isotopic microtest technique was used. The results of cellular proliferation were analysed using ICEstimator software to determine the 50% inhibitory concentration (IC50) values. Results DHA was the most potent among the 6 drugs tested, with IC50 values ranging from 0.8 nM to 0.9 nM (Geometric mean IC50?=?0.8 nM; 95% CI [0.8 - 0.9]). High IC50 values ranged between 0.8 nM to 166.1 nM were reported for lumefantrine (Geometric mean IC50?=?25.1 nM; 95% CI [22.4 - 28.2]). MDA and Q IC50s were significantly higher in CQ-resistant than in CQ-sensitive isolates (P?=?0.0001). However, the opposite occurred for Lum and DHA (P?

2014-01-01

304

Isolation of a wheat (Triticum aestivum L.) mutant in ABA 8?-hydroxylase gene: effect of reduced ABA catabolism on germination inhibition under field condition  

PubMed Central

Pre-harvest sprouting, the germination of mature seeds on the mother plant under moist condition, is a serious problem in cereals. To investigate the effect of reduced abscisic acid (ABA) catabolism on germination in hexaploid wheat (Triticum aestivum L.), we cloned the wheat ABA 8?-hydroxyase gene which was highly expressed during seed development (TaABA8?OH1) and screened for mutations that lead to reduced ABA catabolism. In a screen for natural variation, one insertion mutation in exon 5 of TaABA8?OH1 on the D genome (TaABA8?OH1-D) was identified in Japanese cultivars including ‘Tamaizumi’. However, a single mutation in TaABA8?OH1-D had no clear effect on germination inhibition in double haploid lines. In a screen for a mutation, one deletion mutant lacking the entire TaABA8?OH1 on the A genome (TaABA8?OH1-A), TM1833, was identified from gamma-ray irradiation lines of ‘Tamaizumi’. TM1833 (a double mutant in TaABA8?OH1-A and TaABA8?OH1-D) showed lower TaABA8?OH1 expression, higher ABA content in embryos during seed development under field condition and lower germination than those in ‘Tamaizumi’ (a single mutant in TaABA8?OH1-D). These results indicate that reduced ABA catabolism through mutations in TaABA8?OH1 may be effective in germination inhibition in field-grown wheat. PMID:23641187

Chono, Makiko; Matsunaka, Hitoshi; Seki, Masako; Fujita, Masaya; Kiribuchi-Otobe, Chikako; Oda, Shunsuke; Kojima, Hisayo; Kobayashi, Daisuke; Kawakami, Naoto

2013-01-01

305

High-Voltage Isolation Transformer  

NASA Technical Reports Server (NTRS)

Arcing and field-included surface erosion reduced by electrostatic shields around windings and ferromagnetic core of 80-kilovolt isolation transformer. Fabricated from high-resistivity polyurethane-based material brushed on critical surfaces, shields maintained at approximately half potential difference of windings.

Clatterbuck, C. H.; Ruitberg, A. P.

1985-01-01

306

Manipulation of isolated brain nerve terminals by an external magnetic field using D-mannose-coated ?-Fe2O3 nano-sized particles and assessment of their effects on glutamate transport  

PubMed Central

Summary The manipulation of brain nerve terminals by an external magnetic field promises breakthroughs in nano-neurotechnology. D-Mannose-coated superparamagnetic nanoparticles were synthesized by coprecipitation of Fe(II) and Fe(III) salts followed by oxidation with sodium hypochlorite and addition of D-mannose. Effects of D-mannose-coated superparamagnetic maghemite (?-Fe2O3) nanoparticles on key characteristics of the glutamatergic neurotransmission were analysed. Using radiolabeled L-[14C]glutamate, it was shown that D-mannose-coated ?-Fe2O3 nanoparticles did not affect high-affinity Na+-dependent uptake, tonic release and the extracellular level of L-[14C]glutamate in isolated rat brain nerve terminals (synaptosomes). Also, the membrane potential of synaptosomes and acidification of synaptic vesicles was not changed as a result of the application of D-mannose-coated ?-Fe2O3 nanoparticles. This was demonstrated with the potential-sensitive fluorescent dye rhodamine 6G and the pH-sensitive dye acridine orange. The study also focused on the analysis of the potential use of these nanoparticles for manipulation of nerve terminals by an external magnetic field. It was shown that more than 84.3 ± 5.0% of L-[14C]glutamate-loaded synaptosomes (1 mg of protein/mL) incubated for 5 min with D-mannose-coated ?-Fe2O3 nanoparticles (250 µg/mL) moved to an area, in which the magnet (250 mT, gradient 5.5 ?/m) was applied compared to 33.5 ± 3.0% of the control and 48.6 ± 3.0% of samples that were treated with uncoated nanoparticles. Therefore, isolated brain nerve terminals can be easily manipulated by an external magnetic field using D-mannose-coated ?-Fe2O3 nanoparticles, while the key characteristics of glutamatergic neurotransmission are not affected. In other words, functionally active synaptosomes labeled with D-mannose-coated ?-Fe2O3 nanoparticles were obtained. PMID:24991515

Krisanova, Natalia; Bor?sov, Arsenii; Sivko, Roman; Ostapchenko, Ludmila; Babic, Michal; Horak, Daniel

2014-01-01

307

Field and laboratory investigations of coring-induced damage in core recovered from Marker Bed 139 at the waste isolation pilot plant underground facility  

SciTech Connect

A combined laboratory and field investigation was carried out to determine the extent of coring-induced damage done to samples cored from Marker Bed 139 at the WIPP site. Coring-induced damage, if present, has the potential to significantly change the properties of the material used for laboratory testing relative to the in situ material properties, resulting in misleading conclusions. In particular, connected, crack-like damage could make the permeability of cored samples orders of magnitude greater than the in situ permeabilities. Our approach compared in situ velocity and resistivity measurements with laboratory measurements of the same properties. Differences between in situ and laboratory results could be attributed to differences in the porosity due to cracks. The question of the origin of the changes could not be answered directly from the results of the measurements. Pre-existing cracks, held closed by the in situ stress, could open when the core was cut free, or new cracks could be generated by coring-induced damage. We used core from closely spaced boreholes at three orientations (0{degree}, {plus_minus}45{degrees} relative to vertical) to address the origin of cracks. The absolute orientation of pre-existing cracks would be constant, independent of the borehole orientation. In contrast, cracks induced by coring were expected to show an orientation dependent on that of the source borehole.

Holcomb, D.J.; Zeuch, D.H.; Morin, K.; Hardy, R.; Tormey, T.V.

1995-09-01

308

Relatedness of Macrophomina phaseolina isolates from tallgrass prairie, maize, soybean and sorghum  

E-print Network

Relatedness of Macrophomina phaseolina isolates from tallgrass prairie, maize, soybean and sorghum 143 isolates from maize fields adjacent to tallgrass prairie, nearby sorghum fields, widely dispersed% in the sorghum fields and 80% in the dispersed soybean fields. The isolates were divided into four clusters: one

Garrett, Karen A.

309

Influence of an inner-sphere K+ ion on the magnetic behavior of N2(3-) radical-bridged dilanthanide complexes isolated using an external magnetic field.  

PubMed

The synthesis and full magnetic characterization of a new series of N2(3-) radical-bridged lanthanide complexes [{(R2N)2(THF)Ln}2(?3-?(2):?(2):?(2)-N2)K] [1-Ln; Ln = Gd, Tb, Dy; NR2 = N(SiMe3)2] are described for comprehensive comparison with the previously reported series [K(18-crown-6)(THF)2]{[(R2N)2(THF)Ln]2(?-?(2):?(2)-N2)} (2-Ln; Ln = Gd, Tb, Dy). Structural characterization of 1-Ln crystals grown with the aid of a Nd2Fe13B magnet reveals inner-sphere coordination of the K(+) counterion within 2.9 Å of the N2(3-) bridge, leading to bending of the planar Ln-(N2(3-))-Ln unit present in 2-Ln. Direct current (dc) magnetic susceptibility measurements performed on 1-Gd reveal antiferromagnetic coupling between the Gd(III) centers and the N2(3-) radical bridge, with a strength matching that obtained previously for 2-Gd at J ? -27 cm(-1). Unexpectedly, however, a competing antiferromagnetic Gd(III)-Gd(III) exchange interaction with J ? -2 cm(-1) also becomes prominent, dramatically changing the magnetic behavior at low temperatures. Alternating current (ac) magnetic susceptibility characterization of 1-Tb and 1-Dy demonstrates these complexes to be single-molecule magnets under zero applied dc field, albeit with relaxation barriers (Ueff = 41.13(4) and 14.95(8) cm(-1), respectively) and blocking temperatures significantly reduced compared to 2-Tb and 2-Dy. These differences are also likely to be a result of the competing antiferromagnetic Ln(III)-Ln(III) exchange interactions of the type quantified in 1-Gd. PMID:24580373

Meihaus, Katie R; Corbey, Jordan F; Fang, Ming; Ziller, Joseph W; Long, Jeffrey R; Evans, William J

2014-03-17

310

Isolation and characterization by immunofluorescence, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, western blot, restriction fragment length polymorphism-PCR, 16S rRNA gene sequencing, and pulsed-field gel electrophoresis of Rochalimaea quintana from a patient with bacillary angiomatosis.  

PubMed Central

Rochalimaea quintana was isolated from the blood of a French human immunodeficiency virus-infected patient with bacillary angiomatosis. The isolate showed the typical growth characteristics of Rochalimaea species and was inert when typical biochemical testing was used. The purpose of the present work was to characterize and compare this new isolate with reference strains of R. quintana, Rochalimaea vinsonii, and Rochalimaea henselae by using immunofluorescence, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blot (immunoblot), restriction fragment length polymorphism-PCR of the citrate synthase gene, 16S rRNA gene sequencing, and pulsed-field gel electrophoresis. SDS-PAGE, Western blot, restriction fragment length polymorphism-PCR with TaqI enzyme, and 16S rRNA gene sequencing could differentiate the three Rochalimaea species and allowed characterization of the French isolate as R. quintana. However, identification of the Rochalimaea isolate to the species level was more easily obtained by immunofluorescence with specific murine antisera. Pulsed-field gel electrophoresis allowed differentiation of the French R. quintana isolate from R. quintana Fuller and may serve as an epidemiological tool. Images PMID:7519628

Maurin, M; Roux, V; Stein, A; Ferrier, F; Viraben, R; Raoult, D

1994-01-01

311

Isolated Northern Dunes  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

This VIS image was taken at 81 degrees North latitude during Northern spring. In this region, the dunes are isolated from each other. The dunes are just starting to emerge from the winter frost covering appearing dark with bright crests. These dunes are located on top of ice.

Image information: VIS instrument. Latitude 82.1, Longitude 191.3 East (168.7 West). 19 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2005-01-01

312

Isolated neutron stars in the galaxy: from magnetars to antimagnetars  

SciTech Connect

Using the model with decaying magnetic fields it is possible to describe with one smooth (log-Gaussian) initial magnetic field distribution three types of isolated neutron stars: radiopulsar, magnetars, and cooling close-by compact objects. The same model is used here to make predictions for old accreting isolated neutron stars. It is shown that using the updated field distribution we predict a significant fraction of isolated neutron stars at the stage of accretion despite long subsonic propeller stage.

Boldin, P. A., E-mail: boldin.pavel@gmail.com [Moscow Engineering Physics Institute (State University) (Russian Federation); Popov, S. B., E-mail: polar@sai.msu.ru [Moscow State University, Sternberg Astronomical Institute (Russian Federation)

2012-07-15

313

A second RGD motif in the 1D capsid protein of a SAT1 type foot-and-mouth disease virus field isolate is not essential for attachment to target cells.  

PubMed

The amino acid sequence motif Arg-Gly-Asp (RGD), located in the surface-exposed betaG-betaH loop of the 1D protein of different serotypes and subtypes of foot-and-mouth disease virus (FMDV), is highly conserved and participates in binding of FMDV to susceptible cells. Previous sequence analyses of the 1D-encoding region of a FMDV serotype SAT1 field isolate from Namibia (NAM/307/98) indicated the presence of a second RGD motif upstream of the conserved betaG-betaH loop RGD. The role of these RGD sequences in virus infection was investigated by mutating the betaG-betaH loop RGD to a KGE tripeptide, using a genome-length infectious chimeric cDNA clone. Although the infectivity of the derived mutant viruses for baby hamster kidney cells (BHK-21) was lost, subsequent replacement of the KGE sequence with RGD in the mutant cDNA clone led to recovery of infectious viruses. Furthermore, viral RNA replication could be demonstrated with the genetically engineered mutant and non-mutant viruses. The presence of virus particles in the transfected cells could be also demonstrated by electron microscopy. These results demonstrate that, in contrast to the betaG-betaH loop RGD motif, the second RGD sequence in the capsid protein 1D of NAM/307/98 does not function as a ligand for receptor binding in BHK-21 cells. PMID:17161881

Storey, P; Theron, J; Maree, F F; O'Neill, H G

2007-03-01

314

Magnetically coupled signal isolator  

NASA Technical Reports Server (NTRS)

A current determiner having an output at which representations of input currents are provided having an input conductor for the input current and a current sensor supported on a substrate electrically isolated from one another but with the sensor positioned in the magnetic fields arising about the input conductor due to any input currents. The sensor extends along the substrate in a direction primarily perpendicular to the extent of the input conductor and is formed of at least a pair of thin-film ferromagnetic layers separated by a non-magnetic conductive layer. The sensor can be electrically connected to electronic circuitry formed in the substrate including a nonlinearity adaptation circuit to provide representations of the input currents of increased accuracy despite nonlinearities in the current sensor, and can include further current sensors in bridge circuits.

Black, Jr., William C. (Inventor); Hermann, Theodore M. (Inventor)

2001-01-01

315

Molecular Characterization and Phylogenetic Analysis of New Variants of the Porcine Epidemic Diarrhea Virus in Gansu, China in 2012  

PubMed Central

Between January 2012 and March 2012, the infection rates of porcine epidemic diarrhea virus (PEDV) increased substantially in vaccinated swine herds in many porcine farms in Gansu Province, China. The spike (S) glycoprotein is an important determinant for PEDV biological properties. To determine the distribution profile of PEDV outbreak strains, we sequenced the full-length S gene of five samples from two farms where animals exhibited severe diarrhea and high mortality rates. Five new PEDV variants were identified, and the molecular diversity, phylogenetic relationships, and antigenicity analysis of Gansu field samples with other PEDV reference strains were investigated. A series of insertions, deletions, and mutations in the S gene was found in five PEDV variants compared with classical and vaccine strains. These mutations may provide stronger pathogenicity and antigenicity to the new PEDV variants that influenced the effectiveness of the CV777-based vaccine. Our results suggest that these new PEDV variant strains in Gansu Province might be from South Korean or South China, and the effectiveness of the CV777-based vaccine needs to be evaluated. PMID:23955500

Tian, Yufei; Yu, Zhijun; Cheng, Kaihui; Liu, Yuxiu; Huang, Jing; Xin, Yue; Li, Yuanguo; Fan, Shengtao; Wang, Tiecheng; Huang, Geng; Feng, Na; Yang, Zhenguo; Yang, Songtao; Gao, Yuwei; Xia, Xianzhu

2013-01-01

316

Relatedness of Macrophomina phaseolina isolates from tallgrass prairie, maize, soybean, and sorghum  

E-print Network

Relatedness of Macrophomina phaseolina isolates from tallgrass prairie, maize, soybean, and sorghum 143 isolates from maize fields adjacent to tallgrass prairie, nearby sorghum fields,25 widely similarity was 58% among isolates in the tallgrass prairie, 71% in the maize fields, 75% in the sorghum

Garrett, Karen A.

317

Integrated optical isolators  

E-print Network

Introduction: Optical isolators are important components in lasers. Their main function is to eliminate noise caused by back-reflections into these lasers. The need for integrated isolators comes from the continuing growth ...

Zaman, Tauhid R

2005-01-01

318

Base isolation case study  

E-print Network

The primary objective of this thesis is the introduction of the current code, ASCE 7-05 into the base isolation design and the analysis of base isolation response due to seismic forces. An eight story irregular structure ...

Ching, Kenneth A. (Kenneth Apostol)

2008-01-01

319

Psychopathology of social isolation  

PubMed Central

The most important defining factor of being human is the use of symbolic language. Language or communication problem occurs during the growth, the child will have a higher risk of social isolation and then the survival will be threatened constantly. Today, adolescents and youths are familiar with computer and smart-phone devices, and communication with others by these devices is easy than face-to-face communication. As adolescents and youths live in the comfortable and familiar cyber-world rather than actively participating real society, so they make social isolation. Extreme form of this isolation in adolescents and youths is so-called Socially Withdrawn Youth. In this study, the psychopathological factors inducing social isolation were discussed. Development stages of social isolation in relation with types of social isolation, Ego-syntonic isolation and Ego-dystonic isolation, were also considered. PMID:25061592

Baek, Sang-Bin

2014-01-01

320

Noise cancellation in magnetoencephalography and electroencephalography with isolated reference sensors  

SciTech Connect

An apparatus measures electromagnetic signals from a weak signal source. A plurality of primary sensors is placed in functional proximity to the weak signal source with an electromagnetic field isolation surface arranged adjacent the primary sensors and between the weak signal source and sources of ambient noise. A plurality of reference sensors is placed adjacent the electromagnetic field isolation surface and arranged between the electromagnetic isolation surface and sources of ambient noise.

Kraus Jr., Robert H.; Espy, Michelle A.; Matlachov, Andrei; Volegov, Petr

2010-06-01

321

October 1992 ISOLATOR-11  

E-print Network

generates both high voltage and high current and care should be taken in its operation in any environment The ISOLATOR-11 Stimulus Isolation Unit is a constant current source, and so the voltage it produces Tissues ...7 The Stimulus Artifact 7 Ganging Together Isolators ...8 Power Supply Voltage 9 Grounding

Kleinfeld, David

322

Enhanced cell fusion activity in porcine epidemic diarrhea virus adapted to suckling mice.  

PubMed

Porcine epidemic diarrhea virus (PEDV) is the major causative agent of fatal diarrhea in piglets. To study the pathogenic features of PEDV using a mouse model, PEDV with virulence in mice is required. In pursuit of this, we adapted a tissue-culture-passed PEDV MK strain to suckling mouse brains. PEDV obtained after ten passages through the brains (MK-p10) had increased virulence for mice, and its fusion activity in cultured cells exceeded that of the original strain. However, the replication kinetics of MK and MK-p10 did not differ from each other in the brain and in cultured cells. The spike (S) protein of MK-p10 had four amino acid substitutions relative to the original strain. One of these (an H-to-R substitution at residue 1,381) was first detected in PEDV isolated after eight passages, and both this virus (MK-p8) and MK-p10 showed enhanced syncytium formation relative to the original MK strain and viruses isolated after two, four, and six passages, suggesting the possibility that the H-to-R mutation was responsible for this activity. This mutation could be also involved in the increased virulence of PEDV observed for MK-p10. PMID:20827493

Shirato, Kazuya; Maejima, Madoka; Hirai, Asuka; Ami, Yasushi; Takeyama, Natsumi; Tsuchiya, Kotaro; Kusanagi, Kouich; Nunoya, Tetsuo; Taguchi, Fumihiro

2010-12-01

323

Isolated Curves for Hyperelliptic Curve Cryptography  

E-print Network

We introduce the notion of isolated genus two curves. As there is no known efficient algorithm to explicitly construct isogenies between two genus two curves with large conductor gap, the discrete log problem (DLP) cannot be efficiently carried over from an isolated curve to a large set of isogenous curves. Thus isolated genus two curves might be more secure for DLP based hyperelliptic curve cryptography. We establish results on explicit expressions for the index of an endomorphism ring in the maximal CM order, and give conditions under which the index is a prime number or an almost prime number for three different categories of quartic CM fields. We also derived heuristic asymptotic results on the densities and distributions of isolated genus two curves with CM by any fixed quartic CM field. Computational results, which are also shown for three explicit examples, agree with heuristic prediction with errors within a tolerable range.

Wang, Wenhan

2012-01-01

324

RFLP analysis of rDNA-ITS regions of native non-pathogenic Fusarium oxysporum isolates and their field evaluation for the suppression of Fusarium wilt disease of banana  

Microsoft Academic Search

Fusarium wilt caused by Fusarium oxysporum f. sp. cubense is the most devastating disease of banana affecting commercial cultivars grown worldwide. An attempt has been made to identify\\u000a antagonistic, non-pathogenic Fusarium oxysporum (npFo) isolates from banana soil. A total of 200 rhizosphere soil samples were collected from different commercial cultivars, as\\u000a well as wild bananas. Forty Fusarium isolates were recovered,

R. Thangavelu; A. Jayanthi

2009-01-01

325

Low-Temperature Isolation of Disease-Suppressive Bacteria and Characterization of a Distinctive Group of Pseudomonads  

Microsoft Academic Search

The influence of environmental factors during isolation on the composition of potential biocontrol isolates is largely unknown. Bacterial isolates that efficiently suppressed wheat seedling blight caused by Fusarium culmorum were found by isolating psychrotrophic, root-associated bacteria and by screening them in a bioassay that mimicked field conditions. The impact of individual isolation factors on the disease-suppressive index (DSI) of almost

P. Maria Johansson; Sandra A. I. Wright

2003-01-01

326

NON-TOXIGENIC ASPERGILLUS FLAVUS ISOLATES FOR REDUCING AFLATOXIN IN MISSISSIPPI DELTA CORN  

Technology Transfer Automated Retrieval System (TEKTRAN)

The potential for two non-toxigenic isolates of Aspergillus flavus CT3 and K49 isolated from the Mississippi Delta to reduce aflatoxin contamination of corn was assessed in a field study. These two isolates exhibited comparable growth and aggressiveness as the toxigenic A. flavus isolate F3W4. The...

327

Origin, Evolution, and Genotyping of Emergent Porcine Epidemic Diarrhea Virus Strains in the United States  

PubMed Central

ABSTRACT Coronaviruses are known to infect humans and other animals and cause respiratory and gastrointestinal diseases. Here we report the emergence of porcine epidemic diarrhea virus (PEDV) in the United States and determination of its origin, evolution, and genotypes based on temporal and geographical evidence. Histological lesions in small intestine sections of affected pigs and the complete genomic sequences of three emergent strains of PEDV isolated from outbreaks in Minnesota and Iowa were characterized. Genetic and phylogenetic analyses of the three U.S. strains revealed a close relationship with Chinese PEDV strains and their likely Chinese origin. The U.S. PEDV strains underwent evolutionary divergence, which can be classified into two sublineages. The three emergent U.S. strains are most closely related to a strain isolated in 2012 from Anhui Province in China, which might be the result of multiple recombination events between different genetic lineages or sublineages of PEDV. Molecular clock analysis of the divergent time based on the complete genomic sequences is consistent with the actual time difference, approximately 2 to 3 years, of the PED outbreaks between China (December 2010) and the United States (May 2013). The finding that the emergent U.S. PEDV strains share unique genetic features at the 5?-untranslated region with a bat coronavirus provided further support of the evolutionary origin of PEDV from bats and potential cross-species transmission. The data from this study have important implications for understanding the ongoing PEDV outbreaks in the United States and will guide future efforts to develop effective preventive and control measures against PEDV. PMID:24129257

Huang, Yao-Wei; Dickerman, Allan W.; Piñeyro, Pablo; Li, Long; Fang, Li; Kiehne, Ross; Opriessnig, Tanja; Meng, Xiang-Jin

2013-01-01

328

Mutation and premating isolation  

NASA Technical Reports Server (NTRS)

While premating isolation might be traceable to different genetic mechanisms in different species, evidence supports the idea that as few as one or two genes may often be sufficient to initiate isolation. Thus, new mutation can theoretically play a key role in the process. But it has long been thought that a new isolation mutation would fail, because there would be no other individuals for the isolation-mutation-carrier to mate with. We now realize that premeiotic mutations are very common and will yield a cluster of progeny carrying the same new mutant allele. In this paper, we discuss the evidence for genetically simple premating isolation barriers and the role that clusters of an isolation mutation may play in initiating allopatric, and even sympatric, species divisions.

Woodruff, R. C.; Thompson, J. N. Jr

2002-01-01

329

Genetic and antigenic variability in bovine viral diarrhea virus (BVDV) isolates from Belgium  

Microsoft Academic Search

This report describes the genetic and antigenic variability of bovine viral diarrhea virus strains isolated in Belgium. Part of the 5? untranslated region and the 5? end of the gp53 (E2) coding sequence were amplified by PCR and sequenced. Phylogenetic analysis showed that most field isolates segregated into genotypes Ib or II. Only one out of 28 field isolates belonged

B. Couvreur; C. Letellier; A. Collard; P. Quenon; P. Dehan; C. Hamers; P.-P. Pastoret; P. Kerkhofs

2002-01-01

330

Listeria fleischmannii sp. nov., isolated from cheese.  

PubMed

A study was performed on three isolates (LU2006-1(T), LU2006-2 and LU2006-3), which were sampled independently from cheese in western Switzerland in 2006, as well as a fourth isolate (A11-3426), which was detected in 2011, using a polyphasic approach. The isolates could all be assigned to the genus Listeria but not to any known species. Phenotypic and chemotaxonomic data were compatible with the genus Listeria and phylogenetic analysis based on 16S rRNA gene sequences confirmed that the closest relationships were with members of this genus. However, DNA-DNA hybridization demonstrated that the isolates did not belong to any currently described species. Cell-wall-binding domains of Listeria monocytogenes bacteriophage endolysins were able to attach to the isolates, confirming their tight relatedness to the genus Listeria. Although PCR targeting the central portion of the flagellin gene flaA was positive, motility was not observed. The four isolates could not be discriminated by Fourier transform infrared spectroscopy or pulsed-field gel electrophoresis. This suggests that they represent a single species, which seems to be adapted to the environment in a cheese-ripening cellar as it was re-isolated from the same type of Swiss cheese after more than 5 years. Conjugation experiments demonstrated that the isolates harbour a transferable resistance to clindamycin. The isolates did not exhibit haemolysis or show any indication of human pathogenicity or virulence. The four isolates are affiliated with the genus Listeria but can be differentiated from all described members of the genus Listeria and therefore they merit being classified as representatives of a novel species, for which we propose the name Listeria fleischmannii sp. nov.; the type strain is LU2006-1(T) (?=?DSM 24998(T) ?=?LMG 26584(T)). PMID:22523164

Bertsch, David; Rau, Jörg; Eugster, Marcel R; Haug, Martina C; Lawson, Paul A; Lacroix, Christophe; Meile, Leo

2013-02-01

331

October 1992 ISOLATOR-10  

E-print Network

the control of a data acquisition system, pulse generator, or arbitrary waveform generator. The unit acceptsOctober 1992 ISOLATOR-10 STIMULUS ISOLATION UNIT OPERATOR'S MANUAL Copyright 1992 Axon Instruments form or by any means, electronic, mechanical, photocopying, microfilming, recording, or otherwise

Kleinfeld, David

332

Isolated thoracic aortitis.  

PubMed

Isolated thoracic aortitis is a new pathological entity. We review the histopathological features of this disease, the role of imaging, and diagnostic modalities necessary to make the diagnosis of aortitis and discuss the management of patients with an established diagnosis of isolated thoracic aortitis. PMID:24345043

Omran, Nedal; Laco, Jan; Krbal, Lukas; Vojacek, Jan; Mandak, Jiri

2014-03-01

333

Wrentit Genetic Isolation Map  

USGS Multimedia Gallery

This map of the Thousand Oaks, Calif. area visualizes the degree of genetic isolation being experienced by the wrentit (Chamaea fasciata), a small songbird. USGS and National Park Service biologists discovered that as urban development fragmented the Santa Monica Mountains scrubland into isolated

334

Isolated systems in general relativity  

SciTech Connect

This work comprises two parts. The first part examines radiation effects on composite isolated systems. The author starts by solving the nonlinear asymptotic vacuum field equations in the formalism of Newman and Penrose. He uses a spin weight spherical harmonics representation of the source. The coupling to matter and the equations of motion are obtained through the conservation laws. The results are then applied to the two body problem. Well known phenomena such as the energy and angular momentum loss of radiating systems are recovered. In addition, a new effect is determined whereby the center of mass of such systems is found to recoil. In favorable cases the recoil velocity can attain a few percent of the speed of light. Part two examines the concept of angular momentum for isolated systems in general relativity. It is argued that, on physical grounds, the definition of angular momentum in general relativity should stem from the expression of linear momentum in a way similar to the expression L = rxP used for theories in pseudo-Euclidian spaces. This idea is implemented for isolated systems where, in a sense, a flat background spacetime is available.

Cresswell, A.

1984-01-01

335

Positive isolation disconnect  

NASA Technical Reports Server (NTRS)

A positive isolation disconnect was developed for component replacement in serviced liquid and gaseous spacecraft systems. Initially a survey of feasible concepts was made to determine the optimum method for fluid isolation, sealing techniques, coupling concepts, and foolproofing techniques. The top concepts were then further evaluated, including the fabrication of a semifunctional model. After all tradeoff analyses were made, a final configuration was designed and fabricated for development testing. This resulted in a 6.35 mm (1/4 inch) line and 12.7 mm (1/2 inch) line positive isolation disconnect, each unit consisting of two coupled disconnect halves, each capable of fluid isolation with essentially zero clearance between them for zero leakage upon disconnect half disengagement. An interlocking foolproofing technique was incorporated that prevents uncoupling of disconnect halves prior to fluid isolation.

Rosener, A. A.; Jonkoniec, T. G.

1975-01-01

336

Evaluation of a Reverse Transcriptase Polymerase Chain Reaction Test and Virus Isolation on Field Samples Collected for the Diagnosis of Infectious Hematopoietic Necrosis Virus in Cultured Atlantic Salmon in British Columbia  

Microsoft Academic Search

Infectious hematopoietic necrosis virus (IHNV) has been found to cause disease in cultured salmon of the Pacific Northwest region of North America. Diagnosis of IHNV by virus isolation (VI) can take over 2 weeks. Recently, a rapid reverse transcriptase (RT) polymerase chain reaction (PCR) test on fish tissues has been used for diagnosis. Test performances of the VI and RT

Carol McClure; Sonja Saksida; Grace Karreman; Joanne Constantine; John Robinson; Garth Traxler; Larry Hammell

2008-01-01

337

Pharmacokinetics of tildipirosin in porcine plasma, lung tissue, and bronchial fluid and effects of test conditions on in vitro activity against reference strains and field isolates of Actinobacillus pleuropneumoniae.  

PubMed

The pharmacokinetics of tildipirosin (Zuprevo(®) 40 mg/mL solution for injection for pigs), a novel 16-membered-ring macrolide for the treatment for swine respiratory disease (SRD), was investigated in studies collecting blood plasma and postmortem samples of lung tissue and bronchial fluid (BF) from swine. In view of factors influencing the in vitro activity of macrolides, and for the interpretation of tildipirosin pharmacokinetics in relation to minimum inhibitory concentrations (MIC), additional experiments were conducted to study the effects of pH, carbon dioxide-enriched atmosphere, buffers, and serum on tildipirosin MICs for various reference strains and Actinobacillus (A.) pleuropneumoniae field isolates. After single intramuscular (i.m.) injection at 4 mg/kg body weight, maximum plasma concentration (Cmax) was 0.9 ?g/mL observed within 23 min (Tmax ). Mean residence time from the time of dosing to the time of last measurable concentration (MRTlast) and terminal half-life (T1/2) both were about 4 days. A dose-response relationship with no significant sex effect is observed for area under the plasma concentration-time curve from time 0 to the last sampling time with a quantifiable drug concentration (AUClast) over the range of doses up to 6 mg/kg. However, linear dose proportionality could not be proven with statistical methods. The time-concentration profile of tildipirosin in BF and lung far exceeded that in blood plasma. In lung, tildipirosin concentrations reached 3.1 ?g/g at 2 h, peaked at 4.3 ?g/g at day 1, and slowly declined to 0.8 ?g/g at day 17. In BF, tildipirosin levels were 14.3, 7.0, and 6.5 ?g/g at days 5, 10, and 14. T1/2 in lung was ?7 days. Tildipirosin is rapidly and extensively distributed to the respiratory tract followed by slow elimination. Culture media pH and carbon dioxide-enriched atmosphere (CO2 -EA) had a marked impact on in vitro activity of tildipirosin in reference strains of various rapidly growing aerobic and fastidious bacteria including Histophilus (H.) somni ATCC 700025 and A. pleuropneumoniae ATCC 27090. For A. pleuropneumoniae ATCC 27090 testing conditions without CO2 -EA resulted in reduced acidification of culture media pH and a reduction in the minimum inhibitory concentrations compared to standard in vitro test conditions by 2 log2 dilution steps (4-fold) from 8 to 2 ?g/mL. Supplementary buffering of standard culture media resulted in a reduction in the A. pleuropneumoniae (n = 8) MIC range by 4 log2 dilution steps (16-fold) from 8-16 to 0.5-1 ?g/mL. Incremental supplementation of culture media with 50% serum resulted in noticeable shifts to lower minimum or maximum MICs by at least 2 log2 dilution steps (?4-fold) in all aerobic and fastidious reference strains tested except for Pasteurella (P.) multocida. The MIC of A. pleuropneumoniae ATCC 27090 decreased by 2-4 log2 dilution steps (4 to 16-fold) from 8 to 0.5-2 ?g/mL when 50% serum was added to the standard assay. Considering a higher presence of serum and the rather neutral pH conditions maintained in vivo, it is suggested to take the influence of these factors on in vitro activity into account when interpreting tildipirosin MICs for A. pleuropneumoniae in relation to pharmacokinetics. PMID:22500881

Rose, M; Menge, M; Bohland, C; Zschiesche, E; Wilhelm, C; Kilp, S; Metz, W; Allan, M; Röpke, R; Nürnberger, M

2013-04-01

338

Sequence of the Spike Srotein of the Porcine Epidemic Diarrhoea Virus  

Microsoft Academic Search

The complete sequence of the spike (S) gene of the Brl\\/87 isolate of porcine epidemic diarrhoea virus (PEDV) was determined from cDNA clones. The predicted polypeptide was 1383 amino acids long, contained 29 potential N-linked glycosylation sites and showed structural features similar to those of the coronavirus spike protein. The PEDV S protein, like that of the members of the

Mariela Duarte; Hubert Laude

1994-01-01

339

Mucosal and systemic isotype-specific antibody responses and protection in conventional pigs exposed to virulent or attenuated porcine epidemic diarrhoea virus  

Microsoft Academic Search

Eleven-day-old conventionally reared piglets were inoculated orally with two different doses of the cell-culture adapted strain CV-777 of the porcine epidemic diarrhoea virus (PEDV) or the virulent isolate of the same strain and challenged with the same virulent PEDV 3 weeks later. Pigs inoculated with the two doses of the attenuated virus did not show any typical sign of the

M. L de Arriba; A Carvajal; J Pozo; P Rubio

2002-01-01

340

Cloning and Sequence Analysis of the M gene of Porcine Epidemic Diarrhea Virus LJB\\/03  

Microsoft Academic Search

Porcine epidemic diarrhea virus (PEDV) LJB\\/03 was isolated from the fece of piglets infected with PEDV on a pig farm, Heilongjiang province, China. The M gene of LJB\\/03 was amplified from the RNA extracted directly from the fece samples by RT-PCR and cloned into pMD18-T vector. The M gene cDNA was sequenced and encompasses an open reading frame of 681

Fan Jinghui; Li Yijing

2005-01-01

341

Cloning the structure genes and expression the N gene of porcine epidemic diarrhea virus DX  

Microsoft Academic Search

The structure genes spike (S), nucleocapsid (N), membrane (M), small membrane (sM) of a porcine epidemic diarrhea virus (PEDV)\\u000a strain DX isolated in Gansu province, North-west of China, were cloned, sequenced and compared with published sequences of\\u000a PEDV strains. The nucleotide sequences encoding the entire S, sM, M and N genes open reading frame (ORF) of DX were 4 152,

Jian-qiang Li; Ji-xing Liu; Xi Lan; Jie Cheng; Run Wu; Zhong-Zi Lou; Xiang-ping Yin; Xue-rui Li; Bao-yu Li; Bin Yang; Zhi-yong Li

2009-01-01

342

Isolation of thermotolerant, halotolerant, facultative biosurfactant-producing bacteria  

Microsoft Academic Search

Several facultative bacterial strains tolerant to high temperature and salinity were isolated from the oil reservoir brines\\u000a of an Iranian oil field (Masjed-I Soleyman). Some of these isolates were able to grow up to 60°C and at high concentration\\u000a of NaCl (15% w\\/v). One of the isolates grew at 40°C, while it was able to grow at 15% w\\/v NaCl.

H. Ghojavand; F. Vahabzadeh; M. Mehranian; M. Radmehr; Kh. A. Shahraki; F. Zolfagharian; M. A. Emadi; E. Roayaei

2008-01-01

343

Fault detection and isolation  

NASA Technical Reports Server (NTRS)

In order for a current satellite-based navigation system (such as the Global Positioning System, GPS) to meet integrity requirements, there must be a way of detecting erroneous measurements, without help from outside the system. This process is called Fault Detection and Isolation (FDI). Fault detection requires at least one redundant measurement, and can be done with a parity space algorithm. The best way around the fault isolation problem is not necessarily isolating the bad measurement, but finding a new combination of measurements which excludes it.

Bernath, Greg

1994-01-01

344

MOX Fabrication Isolation Considerations  

SciTech Connect

This document provides a technical position on the preferred level of isolation to fabricate demonstration quantities of mixed oxide transmutation fuels. The Advanced Fuel Cycle Initiative should design and construct automated glovebox fabrication lines for this purpose. This level of isolation adequately protects the health and safety of workers and the general public for all mixed oxide (and other transmutation fuel) manufacturing efforts while retaining flexibility, allowing parallel development and setup, and minimizing capital expense. The basis regulations, issues, and advantages/disadvantages of five potential forms of isolation are summarized here as justification for selection of the preferred technical position.

Eric L. Shaber; Bradley J Schrader

2005-08-01

345

Investigation into the Role of Potentially Contaminated Feed as a Source of the First-Detected Outbreaks of Porcine Epidemic Diarrhea in Canada  

PubMed Central

Summary In January 2014, approximately 9 months following the initial detection of porcine epidemic diarrhea (PED) in the USA, the first case of PED was confirmed in a swine herd in south-western Ontario. A follow-up epidemiological investigation carried out on the initial and 10 subsequent Ontario PED cases pointed to feed as a common risk factor. As a result, several lots of feed and spray-dried porcine plasma (SDPP) used as a feed supplement were tested for the presence of PEDV genome by real-time RT-PCR assay. Several of these tested positive, supporting the notion that contaminated feed may have been responsible for the introduction of PEDV into Canada. These findings led us to conduct a bioassay experiment in which three PEDV-positive SDPP samples (from a single lot) and two PEDV-positive feed samples supplemented with this SDPP were used to orally inoculate 3-week-old piglets. Although the feed-inoculated piglets did not show any significant excretion of PEDV, the SDPP-inoculated piglets shed PEDV at a relatively high level for ?9 days. Despite the fact that the tested PEDV genome positive feed did not result in obvious piglet infection in our bioassay experiment, contaminated feed cannot be ruled out as a likely source of this introduction in the field where many other variables may play a contributing role. PMID:25098383

Pasick, J; Berhane, Y; Ojkic, D; Maxie, G; Embury-Hyatt, C; Swekla, K; Handel, K; Fairles, J; Alexandersen, S

2014-01-01

346

Optical scattering from isolated metal nanoparticles and arrays  

Microsoft Academic Search

Near-field scanning optical microscopy (NSOM) is used to explore the optical scattering from isolated metal nanoparticles (MNPs) and arrays of MNPs. The optical excitation source is an evanescent wave created through total internal reflection of a continuous wave laser beam at the sample-air interface. For optical excitation of isolated Ag and Au MNPs, experimental results show that the scattered light

Gregory A. Wurtz; Jin Seo Im; Stephen K. Gray; Gary P. Wiederrecht

2003-01-01

347

Base isolation: Fresh insight  

SciTech Connect

The objective of the research is a further development of the engineering concept of seismic isolation. Neglecting the transient stage of seismic loading results in a widespread misjudgement: The force of resistance associated with velocity is mostly conceived as a source of damping vibrations, though it is an active force at the same time, during an earthquake type excitation. For very pliant systems such as base isolated structures with relatively low bearing stiffness and with artificially added heavy damping mechanism, the so called `damping`` force may occur even the main pushing force at an earthquake. Thus, one of the two basic pillars of the common seismic isolation philosophy, namely, the doctrine of usefulness and necessity of a strong damping mechanism, is turning out to be a self-deception, sometimes even jeopardizing the safety of structures and discrediting the very idea of seismic isolation. There is a way out: breaking with damping dependancy.

Shustov, V.

1993-07-15

348

Understand Quarantine and Isolation  

MedlinePLUS

... How to Shelter in Place Home School Work Vehicle Understand Quarantine and Isolation Questions & Answers Fact Sheet ... preparedness and response plans. In addition to early detection, rapid diagnosis, and treatment with antibiotics or antivirals, ...

349

Isolated Vascular Vertigo  

PubMed Central

Strokes in the distribution of the posterior circulation may present with vertigo, imbalance, and nystagmus. Although the vertigo due to a posterior circulation stroke is usually associated with other neurologic symptoms or signs, small infarcts involving the cerebellum or brainstem can develop vertigo without other localizing symptoms. Approximately 11% of the patients with an isolated cerebellar infarction present with isolated vertigo, nystagmus, and postural unsteadiness mimicking acute peripheral vestibular disorders. The head impulse test can differentiate acute isolated vertigo associated with cerebellar strokes (particularly within the territory of the posterior inferior cerebellar artery) from more benign disorders involving the inner ear. Acute audiovestibular loss may herald impending infarction in the territory of anterior inferior cerebellar artery. Appropriate bedside evaluation is superior to MRIs for detecting central vascular vertigo syndromes. This article reviews the keys to diagnosis of acute isolated vertigo syndrome due to posterior circulation strokes involving the brainstem and cerebellum. PMID:25328871

2014-01-01

350

Modeling of Axial Magnetic Force and Stiffness of Ring-Shaped Permanent-Magnet Passive Vibration Isolator and Its Vibration Isolating Experiment  

Microsoft Academic Search

Magnetic suspension vibration isolators have attracted more and more attention in the field of semiconductor industry and high precision equipments. A novel ring-shaped permanent-magnet passive vibration isolator is mainly reported in this paper. An analytical expression of axial magnetic force of the isolator is derived and validated by the finite element analysis and experiment. It proves that the analytical expression

Yu Zhu; Qiang Li; Dengfeng Xu; Ming Zhang

2012-01-01

351

Extreme isolated elliptical galaxies  

Microsoft Academic Search

This dissertation presents the results of a detailed search for and the photometric and spectroscopic analysis of nine elliptical galaxies isolated from nearest neighbors of MV < -16.5 by distances in excess of 2.5 megaparsec. The extreme isolation of these galaxies makes them ideal laboratories for the study of galaxy evolution, independent of the continual galaxy-galaxy interaction in the clusters

Christian Edward Aars

2002-01-01

352

Isolated sleep paralysis  

PubMed Central

Sleep paralysis (SP) is a cardinal symptom of narcolepsy. However, little is available in the literature about isolated sleep paralysis. This report discusses the case of a patient with isolated sleep paralysis who progressed from mild to severe SP over 8 years. He also restarted drinking alcohol to be able to fall asleep and allay his anxiety symptoms. The patient was taught relaxation techniques and he showed complete remission of the symptoms of SP on follow up after 8 months. PMID:20711316

Sawant, Neena S.; Parkar, Shubhangi R.; Tambe, Ravindra

2005-01-01

353

CHARACTERIZATION OF LISTERIA MONOCYTOGENES ISOLATED FROM RETAIL FOOD  

Technology Transfer Automated Retrieval System (TEKTRAN)

Listeria monocytogenes isolates (n = 167) recovered from retail deli meats, raw chickens and fresh produce samples were characterized by serogroup identification using PCR, genotyping using pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility testing. Five L. monocytogenes serogr...

354

Characterization of Salmonella Typhimurium isolates associated with septicemia in swine  

PubMed Central

Salmonella Typhimurium is frequently isolated from pigs and may also cause enteric disease in humans. In this study, 33 isolates of S. Typhimurium associated with septicemia in swine (CS) were compared to 33 isolates recovered from healthy animals at slaughter (WCS). The isolates were characterized using phenotyping and genotyping methods. For each isolate, the phage type, antimicrobial resistance, and pulsed-field gel electrophoresis (PFGE) DNA profiles were determined. In addition, the protein profiles of each isolate grown in different conditions were studied by Coomassie Blue-stained sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblot. Various phage types were identified. The phage type PT 104 represented 36.4% of all isolates from septicemic pigs. Resistance to as many as 12 antimicrobial agents, including some natural resistances, was found in isolates from CS and WCS. Many genetic profiles were identified among the PT 104 phage types. Although it was not possible to associate one particular protein with septicemic isolates, several highly immunogenic proteins, present in all virulent isolates and in most isolates from clinically healthy animals, were identified. These results indicated that strains associated with septicemia belong to various genetic lineages that can also be recovered from asymptomatic animals at the time of slaughter. PMID:20357952

Bergeron, Nadia; Corriveau, Jonathan; Letellier, Ann; Daigle, France; Quessy, Sylvain

2010-01-01

355

Genome conservation in isolates of Leptospira interrogans.  

PubMed Central

Reference strains for each of the 23 serogroups of Leptospira interrogans yielded different pulsed-field gel electrophoresis patterns of NotI digestion products. This was also the case for the 14 serovars belonging to serogroup Icterohaemorrhagiae (with one exception). The NotI restriction patterns of 45 clinical leptospiral isolates belonging to serovar icterohaemorrhagiae were analyzed and compared with those of type strains. No differences were observed between isolates from countries of different continents, namely, France, French Guiana, New Caledonia, and Tahiti. The pattern was indistinguishable from that of the reference strain of serovar icterohaemorrhagiae. Images FIG. 1 FIG. 2 FIG. 3 PMID:1938954

Herrmann, J L; Baril, C; Bellenger, E; Perolat, P; Baranton, G; Saint Girons, I

1991-01-01

356

Isolated syndesmosis ankle injury.  

PubMed

Isolated syndesmosis injuries often go unrecognized and are diagnosed as lateral ankle sprains; however, they are more disabling than lateral ankle sprains. The reported incidence of isolated syndesmosis injuries in acute ankle sprains ranges between 1% and 16%. When ankle disability lasts for more than 2 months after an ankle sprain, the incidence increases to 23.6%. Diagnostic workup may include stress radiographs, magnetic resonance imaging, or diagnostic arthroscopy. A simple stress test radiograph may reveal an unstable grade III syndesmosis sprain that may go unrecognized on plain anteroposterior and mortise or lateral radiographs of the ankle. The duration of symptoms in isolated syndesmosis injury is longer and more severe, often leading to chronic symptoms or ankle instability requiring operative stabilization.This article describes the clinical presentation, injury classification, and operative stabilization techniques of isolated syndesmosis injuries. The authors performed their preferred operative stabilization technique for isolated syndesmosis injury-arthroscopic debridement of the ankle with syndesmotic stabilization with a syndesmotic screw-in 4 patients. All patients were evaluated 1 year postoperatively with subjective and objective assessment scales. Three of 4 patients showed good improvement of general subjective ankle symptoms and subjective ankle instability rating and a high Sports Ankle Rating System score after 1 year. PMID:23218625

Valkering, Kars P; Vergroesen, Diederik A; Nolte, Peter A

2012-12-01

357

Clinical, pathological and antigenic aspects of bovine viral diarrhea virus (BVDV) type 2 isolates identified in Brazil  

Microsoft Academic Search

Nucleotide sequencing and phylogenetic analysis of Brazilian bovine viral diarrhea virus (BVDV) field isolates identified four viruses belonging to the genotype 2. Comparison of 5? UTR sequences from these isolates to those of North American BVDV type 2 revealed genomic variations that correlated with the geographic origins of the isolates. Two of the Brazilian type 2 viruses were isolated from

E. F Flores; L. H. G. V Gil; S. A Botton; R Weiblen; J. F Ridpath; L. C Kreutz; C Pilati; D Driemeyer; V Moojen; A. C Wendelstein

2000-01-01

358

Thiogranum longum gen. nov., sp. nov., an obligately chemolithoautotrophic, sulfur-oxidizing bacterium of the family Ectothiorhodospiraceae isolated from a deep-sea hydrothermal field, and an emended description of the genus Thiohalomonas.  

PubMed

A novel, obligately chemolithoautotrophic, sulfur-oxidizing bacterial strain, designated strain gps52(T), was isolated from a rock sample collected near the hydrothermal vents of the Suiyo Seamount in the Pacific Ocean. The cells possessed a Gram-stain-negative-type cell wall and contained menaquinone-8(H4) and menaquinone-9(H4) as respiratory quinones, and C16?:?1?7c, C16?:?0 and C18?:?1?7c as major cellular fatty acids. Neither storage compounds nor extensive internal membranes were observed in the cells. Strain gps52(T) grew using carbon dioxide fixation and oxidation of inorganic sulfur compounds with oxygen as electron acceptor. Optimal growth was observed at 32 °C, pH 6.5 and with 3?% (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain gps52(T) belongs to the family Ectothiorhodospiraceae and is different from any other known bacteria, with sequence similarities of less than 93?%. Based on phenotypic and phylogenetic findings, the isolate is considered to represent a novel genus and species in the family Ectothiorhodospiraceae, and the name Thiogranum longum gen. nov., sp. nov. is proposed. The type strain is gps52(T) (?=?NBRC 101260(T)?=?DSM 19610(T)). An emended description of the genus Thiohalomonas is also proposed. PMID:25336721

Mori, Koji; Suzuki, Ken-ichiro; Yamaguchi, Kaoru; Urabe, Tetsuro; Hanada, Satoshi

2015-01-01

359

Molecular characterization of atoxigenic Aspergillus flavus isolates collected in China.  

PubMed

Aspergillus flavus strains were isolated from peanut fields of Liaoning, Shandong, Hubei and Guangdong Provinces in China, and identified through phenotypic and molecular approaches. Of the 323 A. flavus strains isolated, 76 strains did not produce aflatoxins detectable by UPLC. The incidence of atoxigenic A. flavus strains decreased with increase in temperature and increased with increase in latitude in different geographical locations. Amplification of all the aflatoxin genes in the aflatoxin gene cluster in the atoxigenic isolates showed that there were 25 deletion patterns (A-Y), with 22 deletion patterns identified for the first time. Most of the atoxigenic A. flavus isolates with gene deletions (97%) had deletions in at least one of the four genes (aflT, nor-1, aflR, and hypB), indicating that these four genes could be targeted for rapid identification of atoxigenic strains. The atoxigenic isolates with gene deletions, especially the isolates with large deletions, are potential candidates for aflatoxin control. PMID:24879349

Wei, Dandan; Zhou, Lu; Selvaraj, Jonathan Nimal; Zhang, Chushu; Xing, Fuguo; Zhao, Yueju; Wang, Yan; Liu, Yang

2014-07-01

360

Nucleic acid isolation  

DOEpatents

A method is provided for isolating DNA from eukaryotic cell and flow sorted chromosomes. When DNA is removed from chromosome and cell structure, detergent and proteolytic digestion products remain with the DNA. These products can be removed with organic extraction, but the process steps associated with organic extraction reduces the size of DNA fragments available for experimental use. The present process removes the waste products by dialyzing a solution containing the DNA against a solution containing polyethylene glycol (PEG). The waste products dialyze into the PEG leaving isolated DNA. The remaining DNA has been prepared with fragments containing more than 160 kb. The isolated DNA has been used in conventional protocols without effect on the protocol.

Longmire, J.L.; Lewis, A.K.; Hildebrand, C.E.

1988-01-21

361

Nucleic acid isolation process  

DOEpatents

A method is provided for isolating DNA from eukaryotic cell and flow sorted chromosomes. When DNA is removed from chromosome and cell structure, detergent and proteolytic digestion products remain with the DNA. These products can be removed with organic extraction, but the process steps associated with organic extraction reduce the size of DNA fragments available for experimental use. The present process removes the waste products by dialyzing a solution containing the DNA against a solution containing polyethylene glycol (PEG). The waste products dialyze into the PEG leaving isolated DNA. The remaining DNA has been prepared with fragments containing more than 160 kb. The isolated DNA has been used in conventional protocols without affect on the protocol.

Longmire, Jonathan L. (Los Alamos, NM); Lewis, Annette K. (La Jolla, CA); Hildebrand, Carl E. (Los Alamos, NM)

1990-01-01

362

High voltage gas isolator  

NASA Technical Reports Server (NTRS)

An isolator is provided which has an inlet at ground electrical potential which receives gas, and which has an outlet at a high electrical potential through which gas is discharged, the isolator being compactly and simply constructed while providing a long narrow path that minimizes the possibility of electrical breakdown through the gas. The isolator includes a first element forming a cylindrical core and a cup-shaped second element forming a sleeve portion that closely receives the core. The core has a helical groove on its outside to form a passage between the groove and the inner walls of the sleeve. The core also has a vertical hole extending to the bottom of the core and a radial groove in the bottom of the core that extends between the hole and the bottom of the helical groove.

Brophy, John R. (Inventor)

1988-01-01

363

An optically isolated amplifier  

NASA Astrophysics Data System (ADS)

The design presented was used for biomedical signal detection and monitoring. The amplifier was successfully applied for EMG and ECG research studies. The patient is safely isolated from the processing equipment when using the amplifier. This opto-isolated amplifier was also applied industrially for monitoring mercury arc rectifier control signals. The device has proved itself in an industrial environment as an interface for a microprocessor. This unit can be used whenever large offset voltages are found, and can therefore be put to good use in many power electrical engineering applications.

Smith, C. J.

1982-11-01

364

[Isolated anterior cervical hypertrichosis].  

PubMed

Anterior cervical hypertrichosis was described by Trattner and coworkers in 1991. It consists of a of hair at the anterior cervical level just above the laryngeal prominence. To date, only 28 cases of anterior cervical hypertrichosis have been reported. Although it is normally an isolated finding, it may be associated with mental retardation, hallux valgus, retinal disorders, other hair disorders, facial dysmorphism, or sensory and motor peripheral neuropathy. We report the case of a 27-year-old woman who presented with this condition as an isolated finding. PMID:19268113

Monteagudo, B; Cabanillas, M; de las Heras, C; Cacharrón, J M

2009-01-01

365

Genetic Characterization of Shigella flexneri Isolates in Guizhou Province, China  

PubMed Central

Shigella flexneri is one of the major etiologic causes of shigellosis in Guizhou Province, China. However, the genetic characteristics of circulating isolates are unknown. Phenotypic and molecular profiles of 60 S. flexneri isolates recovered in Guizhou between 1972 to 1982 and 2008 to 2010 were determined. Nine serotypes (1a, 2a, 3a, 1b, 2b, X, Y, 4av and Yv) were identified. Multi-locus sequence typing differentiated the isolates into 20 sequence types (STs); 18 were novel. Four STs, ST 129, ST 100, ST 126 and ST 18, were most abundant, accounting for 65% of the isolates. Thirty-nine NotI-pulsed field gel electrophoresis patterns (pulsotypes, PTs) were observed; eight PTs were represented by more than one isolate with six isolates sharing the PT 13 profile. Multi-locus variable-nucleotide tandem-repeat analysis recognized 44 different types (MTs); seven MTs were represented by more than one isolate and MT 1 was most commonly encountered. Correlation between genetic relationships and serotypes was observed among the isolates studied; the majority of isolates belonging to the same serotype from different years clustered together based on the molecular data. These clustered isolates were also from similar geographical origins. These results enhance our understanding of genetic relationships between S. flexneri in Guizhou Province and can be used to help understand the changing etiology of shigellosis in China. PMID:25617838

Li, Shijun; Sun, Qiangzheng; Wei, Xiaoyu; Klena, John D.; Wang, Jianping; Liu, Ying; Tian, Kecheng; Luo, Xia; Ye, Changyun; Xu, Jianguo; Wang, Dingming; Tang, Guangpeng

2015-01-01

366

Molecular Characterization of Salmonella Isolates of Duck in Comparison to Salmonella Isolates of Chicken and Ruminants  

Microsoft Academic Search

Salmonella species are recognized as a major cause of food borne illness that are closely associated with the consumption of contaminated poultry and egg products. The present study was conducted to compare the cultural, biochemical characteristics, antibiotic sensitivity pattern and the patterns of genomic organization of duck Salmonella isolates associated with chicken, cattle, sheep and goat using pulsed-field gel electrophoresis

Tania Mondal; M Shahidur; Rahman Khan; Munirul Alam; Moushumi Purakayastha

2008-01-01

367

Application of the "best fit" pathotyping assay for evaluation of Russian isolates of Marek's disease virus  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of this study was to investigate the validity of the "best fit" pathotyping assay for testing of field isolates of Marek's disease (MD) virus. Twenty serotype 1 MD viruses were isolated from breeder and commercial flocks in 8 regions of the Russian Federation. These isolates were pat...

368

Pathogenetic observations on pleural effusion disease in rabbits  

Microsoft Academic Search

Summary A pathogenetic study of pleural effusion disease (PED) in rabbits was made, using the virulent PED agent or virus (PEDV) and an avirulent derivate of this isolate. Independent of infective dose within the range examined, the virulent isolate caused fatal clinical disease, whereas the avirulent isolate caused subclinical infection. The two isolates differed in rapidity of initial spread of

K. L. Fennestad

1985-01-01

369

High temperature behavior of multi-region direct current current-voltage spectroscopy and relationship with shallow-trench-isolation-based high-voltage laterally diffused metal-oxide-semiconductor field-effect-transistors reliability  

NASA Astrophysics Data System (ADS)

With the process compatibility with the mainstream standard complementary metal-oxide-semiconductor (CMOS), shallow trench isolation (STI) based laterally diffused metal-oxide-semiconductor (LDMOS) devices have become popular for its better tradeoff between breakdown voltage and performance, especially for smart power applications. A multi-region direct current current-voltage (MR-DCIV) technique with spectroscopic features was demonstrated to map the interface state generation in the channel, accumulation and STI drift regions. High temperature behavior of MR-DCIV spectroscopy was analyzed and a physical model was verified. Degradation of STI-based LDMOS transistors under high temperature reverse bias (HTRB) stress is experimentally studied by MR-DCIV spectroscopy. The impact of interface state location on device electrical characteristics was investigated. Our results show that the major contribution to HTRB degradation, in term of the on-resistance degradation, was attributed to interface state generation under STI drift region.

He, Yandong; Zhang, Ganggang; Zhang, Xing

2014-01-01

370

Rare cell isolation and analysis in microfluidics  

PubMed Central

Rare cells are low-abundance cells in a much larger population of background cells. Conventional benchtop techniques have limited capabilities to isolate and analyze rare cells because of their generally low selectivity and significant sample loss. Recent rapid advances in microfluidics have been providing robust solutions to the challenges in the isolation and analysis of rare cells. In addition to the apparent performance enhancements resulting in higher efficiencies and sensitivity levels, microfluidics provides other advanced features such as simpler handling of small sample volumes and multiplexing capabilities for high-throughput processing. All of these advantages make microfluidics an excellent platform to deal with the transport, isolation, and analysis of rare cells. Various cellular biomarkers, including physical properties, dielectric properties, as well as immunoaffinities, have been explored for isolating rare cells. In this Focus article, we discuss the design considerations of representative microfluidic devices for rare cell isolation and analysis. Examples from recently published works are discussed to highlight the advantages and limitations of the different techniques. Various applications of these techniques are then introduced. Finally, a perspective on the development trends and promising research directions in this field are proposed. PMID:24406985

Chen, Yuchao; Li, Peng; Huang, Po-Hsun; Xie, Yuliang; Mai, John D.; Wang, Lin; Nguyen, Nam-Trung; Huang, Tony Jun

2014-01-01

371

Development and characterization of a magnetorheological elastomer based adaptive seismic isolator  

NASA Astrophysics Data System (ADS)

One of the main shortcomings in current base isolation design/practice is lack of adaptability. As a result, a base isolation system that is effective for one type earthquake may become ineffective or may have adverse effect for other earthquakes. The vulnerability of traditional base isolation systems can be exaggerated by two types of earthquakes, i.e. near-field earthquakes and far-field earthquakes. This paper addresses the challenge facing current base isolation design/practice by proposing a new type of seismic isolator for the base isolation system, namely an adaptive seismic isolator. The novel adaptive seismic isolator utilizes magnetorheological elastomer (MRE) for its field-sensitive material property. Traditional seismic isolator design with a unique laminated structure of steel and MRE layers has been adopted in the novel MRE seismic isolator. To evaluate and characterize the behavior of the MRE seismic isolator, experimental testing was conducted on a shake table facility under harmonic cycling loading. Experimental results show that the proposed adaptive seismic isolator can successfully alter the lateral stiffness and damping force in real time up to 37% and 45% respectively. Based on the successful development of the novel adaptive seismic isolator, a discussion is also extended to the impact and potential applications of such a device in structural control applications in civil engineering.

Li, Yancheng; Li, Jianchun; Li, Weihua; Samali, Bijan

2013-03-01

372

Isolated patellofemoral osteoarthritis  

PubMed Central

Background and purpose The optimal treatment for isolated patellofemoral osteoarthritis is unclear at present. We systematically reviewed the highest level of available evidence on the nonoperative and operative treatment of isolated patellofemoral osteoarthritis to develop an evidenced-based discussion of treatment options. Methods A systematic computerized database search (Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, MEDLINE (PubMed), and EMBASE) was performed in March 2009. The quality of the studies was assessed independently by two authors using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Results We extracted data from 44 articles. The best available evidence for treatment of isolated patellofemoral osteoarthritis is sparse and of generally low methodological quality. Nonoperative treatment using physiotherapy (GRADE: high quality, weak recommendation for use), taping (GRADE: moderate quality, weak recommendation for use), or injection therapy (GRADE: very low quality, weak recommendation for use) may result in short-term relief. Joint-preserving surgical treatment may result in insufficient, unpredictable, or only short-term improvement (GRADE: low quality, weak recommendation against use). Total knee replacement with patellar resurfacing results in predictable and good, durable results (GRADE: low quality, weak recommendation for use). Outcome after patellofemoral arthroplasty in selected patients is good to excellent (GRADE: low quality, weak recommendation for use). Interpretation Methodologically good quality comparative studies, preferably using a patient-relevant outcome instrument, are needed to establish the optimal treatment strategy for patients with isolated patellofemoral osteoarthritis. PMID:20175647

Poolman, Rudolf W; van Kampen, Albert

2010-01-01

373

Biological Isolation Garment  

NASA Technical Reports Server (NTRS)

A spinoff of astronaut's biological garment will allow hospital patients who are highly vulnerable to infection to leave their sterile habitats for several hours, carrying their germ free environment with them. Garments can be used in any of some 200 hospitals where isolation rooms are installed to treat leukemia.

1976-01-01

374

Reproductive Isolation in Angiosperms  

NSDL National Science Digital Library

This resource is a suitable exercise for use in plant reproductive biology laboratory courses. Its purpose is to illustrate mechanisms of isolation in angiosperms by the species Silene by observing the success or failure of inter-specific pollination. This lab exercise is also suitable for courses in plant biology, concepts of the biological species or botany, and evolution.

Alexander F. Motten (Duke University; )

1996-01-01

375

Positive isolation disconnect  

NASA Technical Reports Server (NTRS)

Positive-isolation-disconnect (PID) device with two mating halves prevents leakage or spillover when two fluid lines are disconnected. Each half has shutoff poppet to stop fluid flow. When flow is shut, poppets are flush against each other, leaving no space for fluid to remain it.

Friedell, M. V.

1980-01-01

376

Chemical Kinetics: Isolation Method  

NSDL National Science Digital Library

This site offers an interactive tutorial that guides the student through the Method of Isolation used for the determination of chemical reaction rate laws and rate constants. This tutorial is coupled to others to further guide the student to a better understanding of chemical kinetics.

David N. Blauch

377

Sexual isolation in bacteria  

Microsoft Academic Search

Bacteria exchange genes rarely but are promiscuous in the choice of their genetic partners. Inter-specific recombination has the advantage of increasing genetic diversity and promoting dissemination of novel adaptations, but suffers from the negative effect of importing potentially harmful alleles from incompatible genomes. Bacterial species experience a degree of 'sexual isolation' from genetically divergent organisms ^ recombination occurs more frequently

Jacek Majewski

2001-01-01

378

Isolated Anterior Cervical Hypertrichosis  

Microsoft Academic Search

Anterior cervical hypertrichosis was described by Trattner and coworkers in 1991. It consists of a «tuft» of hair at the anterior cervical level just above the laryngeal prominence. To date, only 28 cases of anterior cervical hypertrichosis have been reported. Although it is normally an isolated finding, it may be associated with mental retardation, hallux valgus, retinal disorders, other hair

B. Monteagudo; M. Cabanillas; C. de las Heras; J. M. Cacharr?n

2009-01-01

379

Morphology of isolated triads  

PubMed Central

The triad is the junctional association of transverse tubule with sarcoplasmic reticulum terminal cisternae. A procedure for the isolation of highly enriched triads from skeletal muscle has been described in the previous paper. In the present study, the structural features of isolated triads have been examined by thin-section, negative-staining, and freeze-fracture electron microscopy. In isolated triads, key features of the structure observed in situ have been retained, including the osmiophilic "feet," junctional structures between the transverse tubule and terminal cisternae. New insight into triad structure is obtained by negative staining, which also enables visualization of feet at the junctional face of the terminal cisternae, whereas smaller surface particles, characteristic of calcium pump protein, are not visualized there. Therefore, the junctional face is different from the remainder of the sarcoplasmic reticulum membrane. Junctional feet as viewed by thin section or negative staining have similar periodicity and extend approximately 100 A from the surface of the membrane. Freeze-fracture of isolated triads reveals blocklike structures associated with the membrane of the terminal cisternae at the junctional face, interjunctional connections between the terminal cisternae and t-tubule, and intragap particles. The intragap particles can be observed to be closely associated with the t-tubule. The structure of isolated triads is susceptible to osmotic and salt perturbation, and examples are given regarding differential effects on transverse tubules and terminal cisternae. Conditions that adversely affect morphology must be considered in experimentation with triads as well as in their preparation and handling. PMID:6187754

1983-01-01

380

Cloning and further sequence analysis of the ORF3 gene of wild- and attenuated-type porcine epidemic diarrhea viruses  

Microsoft Academic Search

The open reading frame (ORF3) genes of the parent DR13, attenuated DR13, KPED-9, P-5V, and 12 field samples were cloned and\\u000a sequenced to further explore the functions of wild- and attenuated-type porcine epidemic diarrhea viruses (PEDVs). Sequencing\\u000a revealed that wild-type PEDVs ORF3 genes had a single ORF of 675 nucleotides encoding a protein of 224 amino acids with a\\u000a predicted

Seong-Jun Park; Hyoung-Joon Moon; Yuzi Luo; Hye-Kwon Kim; Eun-Mi Kim; Jeong-Sun Yang; Dae-Sub Song; Bo-Kyu Kang; Chul-Seung Lee; Bong-Kyun Park

2008-01-01

381

Active Inertial Vibration Isolators And Dampers  

NASA Technical Reports Server (NTRS)

Report describes development of active inertial vibration isolators and dampers in which actuators electromagnet coils moving linearly within permanent magnetic fields in housings, somewhat as though massive, low-frequency voice coils in loudspeakers. Discusses principle of operation, electrical and mechanical considerations in design of actuators, characteristics of accelerometers, and frequency responses of control systems. Describes design and performance of one- and three-degree-of-freedom vibration-suppressing system based on concept.

Laughlin, Darren; Blackburn, John; Smith, Dennis

1994-01-01

382

Thunderstorm electric field modelling  

NASA Technical Reports Server (NTRS)

Calculation of eletric field vectors within and near an isolated thundercloud (which has a given volume charge distribution) is envisaged. The maximum field strength within the thundercloud is calculated. The effects of screening layers, both above and below the thundercloud may be investigated, as well time-dependent potential problem. The study can lead to a better understanding of the charge distributions in a thundercloud, which in turn may shed some light on the actual mechanism of charging of a thundercloud.

Tan, A.

1982-01-01

383

Dynamics of the isolated Galaxy CIG 0314  

NASA Astrophysics Data System (ADS)

In the context of the AMIGA project, we used Fabry-Perot observations in order to study the dynamics of the ionised gas in the isolated galaxy CIG 0314. From the H? observations, we could obtain the velocity field and rotation curve of the galaxy. A detail analysis of the velocity field is done in order to understand the kinematics of the gas to gather clues on the mechanisms which favour or inhibit star formation, in particular along the bar. The visible and dark matter content can be determined, as well as an estimation of the mass of the galaxy.

Verley, S.; Rosado, M.; Repetto, P.; Gabbasov, R.; Verdes-Montenegro, L.; Bergond, G.; Fuentes-Carrera, I.; Durbala, A.

2010-10-01

384

AMIGA Project: Quantification of the Isolation of 950 CIG galaxies  

NASA Astrophysics Data System (ADS)

The role of the environment on galaxy evolution is still not fully understood. In order to quantify and set limits on the role of nurture one must identify and study a sample of isolated galaxies. The AMIGA project "Analysis of the Interstellar Medium of Isolated GAlaxies" is doing a multi-wavelength study of a large sample of isolated galaxies in order to examine their interstellar medium and star formation activity. We processed data for 950 galaxies from the Catalogue of Isolated Galaxies (CIG, Karachentseva 1973) and evaluated their isolation using an automated star-galaxy classification procedure (down to MB ˜ 17.5) on large digitised POSS-I fields surrounding each isolated galaxy (within a projected radius of at least 0.5 Mpc). We defined, compared and discussed various criteria to quantify the degree of isolation for these galaxies: e.g. Karachentseva’s revised criterion, local surface density computations, estimation of the external tidal force affecting each is olated galaxy. We found galaxies violating Karachentseva’s original criterion, and we defined various subsamples of galaxies according to their degree of isolation. Additionally, we sought for the redshifts of the primary and companion galaxies to access the radial dimension. We also applied our pipeline to triplets, compact groups and clusters and interpret the isolated galaxy population in light of these control samples.

Verley, S.; Leon, S.; Verdes-Montenegro, L.; Combes, F.; Sabater, J.; Sulentic, J.; Bergond, G.; Espada, D.; Lisenfeld, U.; Odewahn, S. C.

2010-10-01

385

Genetic analysis of multiple vancomycin-resistant Enterococcus isolates obtained serially from two long-term-care patients.  

PubMed

Fifty-eight vancomycin-resistant enterococcal isolates were obtained from two patients over 9 weeks. Numerous pulsed-field gel electrophoresis fingerprinting types were isolated from each patient. By PCR, all isolates were vanA+. However, many isolates from patient B were found to lack vanA by hybridization. Our results demonstrate the importance of examining multiple isolates, especially from patients who are at high risk of infection. PMID:9650975

Schoonmaker, D J; Bopp, L H; Baltch, A L; Smith, R P; Rafferty, M E; George, M

1998-07-01

386

High voltage isolation transformer  

NASA Technical Reports Server (NTRS)

A high voltage isolation transformer is provided with primary and secondary coils separated by discrete electrostatic shields from the surfaces of insulating spools on which the coils are wound. The electrostatic shields are formed by coatings of a compound with a low electrical conductivity which completely encase the coils and adhere to the surfaces of the insulating spools adjacent to the coils. Coatings of the compound also line axial bores of the spools, thereby forming electrostatic shields separating the spools from legs of a ferromagnetic core extending through the bores. The transformer is able to isolate a high constant potential applied to one of its coils, without the occurrence of sparking or corona, by coupling the coatings, lining the axial bores to the ferromagnetic core and by coupling one terminal of each coil to the respective coating encasing the coil.

Clatterbuck, C. H.; Ruitberg, A. P. (inventors)

1985-01-01

387

Isolation of Carbon Nanostructures  

SciTech Connect

Carbon nanostructures such a single wall carbon nanotubes (SWCNT), double wall carbon nanotubes (DWCNT) and fullerene peapods (e.g. C70 at SWCNT) usually occur in the form of bundles. Here, we present application of a novel simple and versatile method for deposition of small isolated nanoribbons of carbon nanotubes on annealed gold surface. The nanoribbons were characterized by Raman spectroscopy and exhibit characteristic features of individual carbon nanostructures. The resonance condition allowed the observation of a distinct spectrum of one inner tube in the nanoribbon from DWCNT. The signal of inner tubes of isolated DWCNT nanoribbons was found to be up to 50 times stronger than the sum of signals of the corresponding tubes in buckypaper sample. This dramatic enhancement is assigned to SERS (surface enhanced resonant Raman scattering) effect.

Kalbac, Martin; Kavan, Ladislav [J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, CZ-182 23 Prague 8 (Czech Republic); Leibniz Institute of Solid State and Materials Research, Helmholtzstr. 20, D - 01069 Dresden (Germany); Pelouchova, Hana; Janda, Pavel; Zukalova, Marketa [J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, CZ-182 23 Prague 8 (Czech Republic); Dunsch, Lothar [Leibniz Institute of Solid State and Materials Research, Helmholtzstr. 20, D - 01069 Dresden (Germany)

2005-09-27

388

Pump isolation valve  

DOEpatents

The pump isolation valve provides a means by which the pump may be selectively isolated from the remainder of the coolant system while being compatible with the internal hydraulic arrangement of the pump during normal operation of the pump. The valve comprises a valve cylinder disposed around the pump and adjacent to the last pump diffuser with a turning vane attached to the lower end of the valve cylinder in a manner so as to hydraulically match with the discharge diffuser. The valve cylinder is connected to a drive means for sliding the valve cylinder relative to the diffuser support cylinder so as to block flow in either direction through the discharge diffuser when the valve is in the closed position and to aid in the flow of the coolant from the discharge diffuser by means of the turning vane when the valve is in the open position.

Kinney, Calvin L. (Penn Hills, PA); Wetherill, Todd M. (Lower Burrell, PA)

1983-08-02

389

Isolation of platelet granules.  

PubMed

Functional analysis of platelet intracellular structures requires isolation and purification of these cellular compartments. With regard to the function of platelets, both, dense (delta) and alpha granules are relevant target structures. However, the availability of sufficient purification protocols for these structures is rather limited. This unit describes two protocols for isolation and purification of platelet granule structures. The Basic Protocol describes a new technique based on immunolabeling with target-specific antibodies followed by magnetic sorting, whereas the Alternate Protocol describes the more traditional procedure based on differential centrifugation and density-based sedimentation. For both methods, the degree of granule purification can be most easily determined by immunoblotting using various antibodies that recognize structure-specific proteins. The immunomagnetic sorting method is especially good for studies requiring highly purified material (e.g., for the identification of specific transporters and receptors). PMID:20235104

Niessen, Juliane; Jedlitschky, Gabriele; Greinacher, Andreas; Kroemer, Heyo K

2010-03-01

390

The isolated fourth ventricle  

PubMed Central

Isolated enlargement of the fourth ventricle, or ‘encysted’ fourth ventricle is a rare late complication following shunt insertion of the lateral ventricles for hydrocephalus. Caudal and rostral obstruction of the fourth ventricle and its subsequent dilation results in compression of adjacent cerebellum and brain stem structures; treatment with further shunt insertion directly to the fourth ventricle is invariably successful. There is potential for diagnostic delay, when clinical symptoms and signs of cerebellar and brain stem compromise are unrecognised or attributed to other factors, and attention on the CT is focused on the lateral ventricular system and the already existing  ventriculoperitoneal shunt, which will appear unchanged from previous scans. We report two cases with isolated fourth ventricular obstruction and review the literature to highlight the importance of recognising this condition. PMID:23559656

Ali, Khalid; Nannapaneni, Ravindra; Hamandi, Khalid

2013-01-01

391

Comparative evaluation of an automated ribotyping system versus pulsed-field gel electrophoresis for epidemiological typing of clinical isolates of Escherichia coli and Pseudomonas aeruginosa from patients with recurrent gram-negative bacteremia  

Microsoft Academic Search

Ribotyping and macrorestriction analysis of chromosomal DNA using pulsed-field gel electrophoresis (PFGE) are among the more useful molecular epidemiologic typing methods. Because these techniques are labor intensive, automation of one or more steps may allow clinical laboratories to apply molecular typing methods. We compared the recently developed automated ribotyping system, the RiboPrinter™ Microbial Characterization System (DuPont), with PFGE as a

M. A. Pfaller; C. Wendt; R. J. Hollis; R. P. Wenzel; S. J. Fritschel; J. J. Neubauer; L. A. Herwaldt

1996-01-01

392

DNA Isolation from Onion  

NSDL National Science Digital Library

Many students find studying DNA difficult because it is so small that the concepts are quite abstract. This lab enables students to work with DNA concretely by easily isolating chromosomal DNA using the same basic tools and methods that scientists use. The lab is a good introduction to using pipets and to using the metric system. If the chemistry of the solutions is taught it is also a great practical application.

BEGIN:VCARD VERSION:2.1 FN:Kate Dollard N:Dollard; Kate ORG:Cambridge Rindge and Latin REV:2005-04-12 END:VCARD

1994-07-30

393

A novel approach for the isolation of the sound and pseudo-sound contributions from near-field pressure fluctuation measurements: analysis of the hydroacoustic and hydrodynamic perturbation in a propeller-rudder system  

NASA Astrophysics Data System (ADS)

The main scope of the present work is to investigate the mechanisms underlying the hydroacoustic and hydrodynamic perturbations in a rudder operating in the wake of a free running marine propeller. The study consisted of detailed near-field pressure fluctuation measurements which were acquired on the face and back surfaces of the rudder, at different deflection angles. To this aim, a novel wavelet-filtering procedure was applied to separate and analyze distinctly the acoustic and hydrodynamic components of the recorded near-field pressure signals. The filtering procedure undertakes the separation of intermittent pressure peaks induced by the passage of eddy structures, interpreted as pseudo-sound, from homogenous background fluctuations, interpreted as sound. The use of wavelet in the filtering procedure allows to overcome the limitations of the earlier attempts based on frequency (wave number) band-pass filtering, retrieving the overall frequency content of both the acoustic and the hydrodynamic components and returning them as independent signals in the time domain. Acoustic and hydrodynamic pressure distributions were decomposed harmonically and compared to the corresponding topologies of the vorticity field, derived from earlier LDV measurements performed by Felli and Falchi (Exp Fluids 51(5):1385-1402, 2011). The study highlighted that the acoustic perturbation is mainly correlated with the unsteady load variations of the rudder and to the shear layer fluctuations of the propeller streamtube. Conversely, the dynamics of the propeller tip and hub vortices underlies the hydrodynamic perturbation.

Felli, Mario; Grizzi, Silvano; Falchi, Massimo

2014-01-01

394

The effect of various Mycoplasma bovis isolates on bovine leukocyte responses.  

PubMed

Mycoplasma bovis (M. bovis) contributes to a number of clinical syndromes in cattle; in particular, chronic pneumonia that is poorly responsive to therapy has been increasingly recognized as an important cause of morbidity, mortality, and financial loss. M. bovis impairs host immune function, but little is known about whether field isolates vary significantly in their effect on immune function. This research tested the hypothesis that different field isolates vary in their ability to suppress cellular metabolism and cellular production of radical oxygen species (ROS) by bovine leukocytes. Total blood leukocytes from 6 cattle were exposed to six field isolates, two diagnostic lab isolates, and two high passage laboratory isolates of M. bovis, and ROS production was measured by oxidation of dihydrorhodamine 123 (DHR-123). Cellular metabolism was measured by reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Significant differences in the response to some field isolates were identified. Three field isolates and both diagnostic lab isolates significantly decreased ROS production by leukocytes from multiple cattle, while the high pass laboratory isolates did not. In contrast, MTT reduction was not significantly impaired by any of the M. bovis strains tested. M. bovis impairs ROS production by bovine leukocytes; the magnitude of the effect appears to be isolate-dependent, and is not related to a general impairment of cellular metabolism. Chronic M. bovis infection in some cattle may be related to impaired ability of leukocytes to produce ROS when exposed to M. bovis. PMID:20189247

Wiggins, M C; Woolums, A R; Hurley, D J; Sanchez, S; Ensley, D T; Donovan, D

2011-01-01

395

Molecular characterization of Mycoplasma gallisepticum isolates from Jordan.  

PubMed

Two groups of Mycoplasma gallisepticum (MG) isolates (n = 24) from Jordan were analyzed by molecular methods and compared with other Middle Eastern isolates, related international isolates, and reference strains. The first group (n = 19) was isolated from July 2004 to January 2005 (isolation period A), and the newer group (n = 5) from June 2007 to April 2008 (isolation period B). The groups of isolates are from chicken flocks from northern Jordan, but are not from the same farms. None of the flocks were vaccinated for MG. Random amplified polymorphic DNA analysis, targeted sequencing of the partial MG cytadhesin 2 (mgc2), and the MG 16S-23S rRNA intergenic spacer region (IGSR) divided the Jordanian isolates into two groups. All of the 19 isolates from time period A, in addition to two isolates from time period B, were indistinguishable from the F strain. Three of five isolates from time period B were characterized as wild types and were indistinguishable from each other. The wild-type field strain was readily distinguished from the F strain. It was 91% and 96.4% similar to the F strain based on Clustal-W alignments of sequences of mgc2 and IGSR, respectively. Sequence similarity of mgc2 gene of the Jordan wild-type strain to isolates from Israel and Egypt ranged from 96.5% to 100%, whereas for IGSR it was 99.4%-100%. We theorize that the F-strain live MG vaccine, commonly used in Jordan prior to 2007, was transmitted to nonvaccinated poultry in the region and was a predominant genotype during time period A. PMID:21793435

Gharaibeh, Saad; Laibinis, Victoria; Wooten, Ruth; Stabler, Lisa; Ferguson-Noel, Naola

2011-06-01

396

Theoretical study on hula-twist motion of penta-2,4-dieniminium on the S 1 surface under isolated condition by the complete active space self-consistent field theory  

NASA Astrophysics Data System (ADS)

Hula-twist (HT) motion of tZt-penta-2,4-dieniminium (PDI) on the S 1 surface is studied on the basis of complete active space self-consistent field (CASSCF) theory. An S 1/S 0 crossing region (a segment of the S 1/S 0 conical intersection hyperline) along a HT coordinate (simultaneous rotation of the central double bond and an adjacent single bond) is characterized. One-dimensional relaxed scan calculation along the postulated HT coordinate shows no barrier up to the S 1/S 0 crossing region, suggesting the possible involvement of the HT process in a fast photochemical reaction in constrained states.

Sumita, Masato; Saito, Kazuya

2006-06-01

397

Isolation of Salmonella typhimurium from outbreak-associated cake mix.  

PubMed

During May and June of 2005, 26 persons in several states were infected by a single strain (isolates indistinguishable by pulsed-field gel electrophoresis) of Salmonella enterica serotype Typhimurium after eating cake batter ice cream. The cake mix used to prepare the cake batter in the ice cream was implicated by epidemiologic investigation as the source of Salmonella contamination. Initial tests did not detect Salmonella in cake mix collected during the outbreak investigation. The objective of this study was to evaluate different procedures to isolate Salmonella from the implicated cake mix, cake, and ice cream. All outbreak-associated food samples (14 samples) were collected during the outbreak investigation by health departments of several of the states involved. Different combinations of Salmonella isolation procedures, including sample size, preenrichment broth, enrichment broth, enrichment temperature, and isolation medium, were used. Salmonella Typhimurium was isolated from two cake mix samples; the food isolates were indistinguishable from the outbreak pattern by pulsed-field gel electrophoresis subtyping. Universal preenrichment broth was substantially better than was lactose broth for preenrichment, and tetrathionate broth was better than was Rappaport-Vassiliadis broth for isolating Salmonella from the two positive cake mix samples. Although more typical Salmonella colonies were observed on plates from enrichment cultures grown at 35 degrees C, more confirmed Salmonella isolates were obtained from plates of enrichment cultures grown at 42 degrees C. Brilliant green agar, xylose lysine tergitol 4 agar, xylose lysine desoxycholate agar, Hektoen enteric agar, and bismuth sulfite agar plates were equally effective in isolating Salmonella from cake mix. The best combination of preenrichment-enrichment conditions for isolating the outbreak strain of Salmonella was preenrichment of cake mix samples in universal preenrichment broth at 35 degrees C for 24 h, followed by enrichment in tetrathionate broth at 42 degrees C for 24 h. PMID:17477273

Zhang, Guodong; Ma, Li; Patel, Nehal; Swaminathan, Bala; Wedel, Stephanie; Doyle, Michael P

2007-04-01

398

Molecular characterization of Mycoplasma gallisepticum isolates from turkeys.  

PubMed

Mycoplasma gallisepticum was isolated from several turkey flocks at different locations in the United States that were clinically affected with respiratory disease. Five of these isolates from four series of outbreaks had patterns similar to the 6/85 vaccine strain of M. gallisepticum by random amplified polymorphic DNA (RAPD) analysis using three different primer sets, whereas with a fourth primer set (OPA13 and OPA14), only two of the isolates were similar to 6/85. Results obtained by sequencing portions of the pvpA, gapA, and mgc2 genes and an uncharacterized surface lipoprotein gene indicated that the field isolates had DNA sequences that ranged from 97.6% to 100%, similar to the 6/85 results. In some of the outbreaks there was an indirect association with the presence of commercial layers in the area that had been vaccinated with this vaccine strain, but there was no known close association with vaccinated birds in any of the outbreaks. Turkeys were challenged with two of the field isolates and with 6/85 vaccine strain. Turkeys challenged with the field isolates developed respiratory disease with airsacculitis and a typical M. gallisepticum antibody response, whereas birds challenged with 6/85 developed no respiratory signs or lesions and developed only a weak antibody response. Although these isolates were very similar to the 6/85 vaccine strain, it was not possible to prove that they originated from the vaccine strain-it is possible that they could be naturally occurring field isolates. PMID:15529978

Kleven, S H; Fulton, R M; García, M; Ikuta, V N; Leiting, V A; Liu, T; Ley, D H; Opengart, K N; Rowland, G N; Wallner-Pendleton, E

2004-09-01

399

Hollow-cylinder waveguide isolators for use at millimeter wavelengths  

NASA Technical Reports Server (NTRS)

The device considered in this study is a semiconductor waveguide isolator consisting of a hollow column of a semiconductor mounted coaxially in a circular waveguide in a longitudinal dc magnetic field. An elementary and physical analysis based on the excitation of plane waves in the guide and a more rigorous mode-matching analysis (MMA) are presented. These theoretical predictions are compared with experimental results for an InSb isolator at 94 GHz and 75 K.

Kanda, M.; May, W. G.

1974-01-01

400

Colours of isolated galaxies from 2MIG  

E-print Network

The properties of isolated galaxies are mainly driven by intrinsic evolution and not by the external influence of their environments. Therefore the isolated galaxy sample may be considered as a reference sample to study different environmental effects. We made detailed comparisons between the near-infrared (2MASS) and optical (SDSS) colours of the 2MASS XSC selected sample of isolated 2MIG galaxies and with other objects from the wide range of denser environments (field, groups/clusters, triplets and pairs). We found that early type galaxies show similar (J-H)rest and (g-r)rest colours practically in all types of environments. Exception is for the massive early type galaxies located in compact pairs with high velocity difference (dV~180 km/s), which are significantly redder and brighter than isolated galaxies. We assume that these pairs are located in the centres of more populated groups and clusters. In general, galaxies in groups and pairs of spiral and late morphological types have redder near-infrared col...

Melnyk, O; Karachentseva, V

2013-01-01

401

Isolation of circulating tumor cells by dielectrophoresis.  

PubMed

Dielectrophoresis (DEP) is an electrokinetic method that allows intrinsic dielectric properties of suspended cells to be exploited for discrimination and separation. It has emerged as a promising method for isolating circulation tumor cells (CTCs) from blood. DEP-isolation of CTCs is independent of cell surface markers. Furthermore, isolated CTCs are viable and can be maintained in culture, suggesting that DEP methods should be more generally applicable than antibody-based approaches. The aim of this article is to review and synthesize for both oncologists and biomedical engineers interested in CTC isolation the pertinent characteristics of DEP and CTCs. The aim is to promote an understanding of the factors involved in realizing DEP-based instruments having both sufficient discrimination and throughput to allow routine analysis of CTCs in clinical practice. The article brings together: (a) the principles of DEP; (b) the biological basis for the dielectric differences between CTCs and blood cells; (c) why such differences are expected to be present for all types of tumors; and (d) instrumentation requirements to process 10 mL blood specimens in less than 1 h to enable routine clinical analysis. The force equilibrium method of dielectrophoretic field-flow fractionation (DEP-FFF) is shown to offer higher discrimination and throughput than earlier DEP trapping methods and to be applicable to clinical studies. PMID:24662940

Gascoyne, Peter R C; Shim, Sangjo

2014-01-01

402

Isolation of Circulating Tumor Cells by Dielectrophoresis  

PubMed Central

Dielectrophoresis (DEP) is an electrokinetic method that allows intrinsic dielectric properties of suspended cells to be exploited for discrimination and separation. It has emerged as a promising method for isolating circulation tumor cells (CTCs) from blood. DEP-isolation of CTCs is independent of cell surface markers. Furthermore, isolated CTCs are viable and can be maintained in culture, suggesting that DEP methods should be more generally applicable than antibody-based approaches. The aim of this article is to review and synthesize for both oncologists and biomedical engineers interested in CTC isolation the pertinent characteristics of DEP and CTCs. The aim is to promote an understanding of the factors involved in realizing DEP-based instruments having both sufficient discrimination and throughput to allow routine analysis of CTCs in clinical practice. The article brings together: (a) the principles of DEP; (b) the biological basis for the dielectric differences between CTCs and blood cells; (c) why such differences are expected to be present for all types of tumors; and (d) instrumentation requirements to process 10 mL blood specimens in less than 1 h to enable routine clinical analysis. The force equilibrium method of dielectrophoretic field-flow fractionation (DEP-FFF) is shown to offer higher discrimination and throughput than earlier DEP trapping methods and to be applicable to clinical studies. PMID:24662940

Gascoyne, Peter R. C.; Shim, Sangjo

2014-01-01

403

The NASA Langley Isolator Dynamics Research Lab  

NASA Technical Reports Server (NTRS)

The Isolator Dynamics Research Lab (IDRL) is under construction at the NASA Langley Research Center in Hampton, Virginia. A unique test apparatus is being fabricated to support both wall and in-stream measurements for investigating the internal flow of a dual-mode scramjet isolator model. The test section is 24 inches long with a 1-inch by 2-inch cross sectional area and is supplied with unheated, dry air through a Mach 2.5 converging-diverging nozzle. The test section is being fabricated with two sets (glass and metallic) of interchangeable sidewalls to support flow visualization and laser-based measurement techniques as well as static pressure, wall temperature, and high frequency pressure measurements. During 2010, a CFD code validation experiment will be conducted in the lab in support of NASA s Fundamental Aerodynamics Program. This paper describes the mechanical design of the Isolator Dynamics Research Lab test apparatus and presents a summary of the measurement techniques planned for investigating the internal flow field of a scramjet isolator model.

Middleton, Troy F.; Balla, Robert J.; Baurle, Robert A.; Humphreys, William M.; Wilson, Lloyd G.

2010-01-01

404

Geological problems in radioactive waste isolation  

SciTech Connect

The problem of isolating radioactive wastes from the biosphere presents specialists in the fields of earth sciences with some of the most complicated problems they have ever encountered. This is especially true for high level waste (HLW) which must be isolated in the underground and away from the biosphere for thousands of years. Essentially every country that is generating electricity in nuclear power plants is faced with the problem of isolating the radioactive wastes that are produced. The general consensus is that this can be accomplished by selecting an appropriate geologic setting and carefully designing the rock repository. Much new technology is being developed to solve the problems that have been raised and there is a continuing need to publish the results of new developments for the benefit of all concerned. The 28th International Geologic Congress that was held July 9--19, 1989 in Washington, DC provided an opportunity for earth scientists to gather for detailed discussions on these problems. Workshop W3B on the subject, Geological Problems in Radioactive Waste Isolation -- A World Wide Review'' was organized by Paul A Witherspoon and Ghislain de Marsily and convened July 15--16, 1989 Reports from 19 countries have been gathered for this publication. Individual papers have been cataloged separately.

Witherspoon, P.A. (ed.)

1991-01-01

405

Antimicrobial Resistance in Enterococci Isolated from Turkey Flocks Fed Virginiamycin  

PubMed Central

From 125 separate cloacal cultures from three turkey flocks fed virginiamycin, 104 Enterococcus faecium and 186 Enterococcus faecalis isolates were obtained. As the turkeys aged, there was a higher percentage of quinupristin-dalfopristin-resistant E. faecium isolates, with isolates from the oldest flock being 100% resistant. There were no vancomycin-resistant enterococci. Results of pulsed-field gel electrophoresis (PFGE) indicated there were 11 PFGE types of E. faecalis and 7 PFGE types of E. faecium that were in more than one group of flock cultures. PMID:9517958

Welton, L. A.; Thal, L. A.; Perri, M. B.; Donabedian, S.; McMahon, J.; Chow, J. W.; Zervos, M. J.

1998-01-01

406

Investigation of mercury thruster isolators  

NASA Technical Reports Server (NTRS)

Mercury ion thruster isolator lifetime tests were performed using different isolator materials and geometries. Tests were performed with and without the flow of mercury through the isolators in an oil diffusion pumped vacuum facility and cryogenically pumped bell jar. The onset of leakage current in isolators occurred in time intervals ranging from a few hours to many hundreds of hours. In all cases, surface contamination was responsible for the onset of leakage current and subsequent isolator failure. Rate of increase of leakage current and the leakage current level increased approximately exponentially with isolator temperature. Careful attention to shielding techniques and the elimination of sources of metal oxides appear to have eliminated isolator failures as a thruster life limiting mechanism.

Mantenieks, M. A.

1973-01-01

407

Lymphoproliferative responses and protection in conventional piglets inoculated orally with virulent or attenuated porcine epidemic diarrhoea virus  

Microsoft Academic Search

Lymphocyte proliferative responses were evaluated in mucosal (mesenteric lymph nodes) and systemic (spleen and blood) lymphoid tissues of conventional piglets inoculated with the virulent or attenuated isolates of porcine epidemic diarrhoea virus (PEDV) strain CV-777 and challenged 21 days later with the virulent isolate of the same virus. A lymphoproliferative assay was developed in which mononuclear cells isolated from lymphoid

M. L de Arriba; A Carvajal; J Pozo; P Rubio

2002-01-01

408

Highly isolated photodetectors  

SciTech Connect

An array of photodetectors is described incorporating a PNP vertical structure in a monosilicon substrate with individual photodetectors optically and electrically isolated from one another by open or oxide filled grooves. Both PN junctions of the PNP structure or originally reverse biased with one junction acting as the photodetector may operate in the forward biased photovoltaic mode with high radiant energy intensity. The minority carriers injected into the N region are absorbed by the other PN junction providing base-collector transistor action to prevent blooming.

Bluzer, N.; Borsuk, G.M.; Kub, F.J.; Turley, A.P.

1984-12-11

409

Genetic Diversity of Pectobacterium carotovorum subsp. brasiliensis Isolated in Korea  

PubMed Central

The plant pathogenic bacterial genus Pectobacteirum consists of heterogeneous strains. The P. carotovorum species is a complex strain showing divergent characteristics, and a new subspecies named P. carotovorum subsp. brasiliensis has been identified recently. In this paper, we re-identified the P. carotovorum subsp. brasiliensis isolates from those classified under the subspecies carotovorum and newly isolated P. carotovorum subsp. brasiliensis strains. All isolates were able to produce plant cell-wall degrading enzymes such as pectate lyase, polygalacturonase, cellulase and protease. We used genetic and biochemical methods to examine the diversity of P. carotovorum subsp. brasiliensis isolates, and found genetic diversity within the brasiliensis subsp. isolates in Korea. The restriction fragment length polymorphism analysis based on the recA gene revealed a unique pattern for the brasiliensis subspecies. The Korean brasiliensis subsp. isolates were divided into four clades based on pulsed-field gel electrophoresis. However, correlations between clades and isolated hosts or year could not be found, suggesting that diverse brasiliensis subsp. isolates existed. PMID:25288994

Lee, Dong Hwan; Kim, Jin-Beom; Lim, Jeong-A; Han, Sang-Wook; Heu, Sunggi

2014-01-01

410

Braking index of isolated pulsars  

NASA Astrophysics Data System (ADS)

Isolated pulsars are rotating neutron stars with accurately measured angular velocities ? , and their time derivatives that show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a question of detailed debate, the commonly accepted view is that it arises through emission of magnetic dipole radiation (MDR) from a rotating magnetized body. Other processes, including the emission of gravitational radiation, and of relativistic particles (pulsar wind), are also being considered. The calculated energy loss by a rotating pulsar with a constant moment of inertia is assumed proportional to a model dependent power of ? . This relation leads to the power law ? ? =-K ?n where n is called the braking index. The MDR model predicts n exactly equal to 3. Selected observations of isolated pulsars provide rather precise values of n , individually accurate to a few percent or better, in the range 1 isolated pulsars are not known) ranging from 1.0 - 2.2 M? , and fixed magnetic dipole moment and inclination angle between the rotational and magnetic field axes. The results are used to solve for the value of the braking index as a function of frequency, and find the effect of the choice of the EoS, MB. The density profile of a star with a given MB is calculated to determine the transition between the crust and the core and used in estimation of the effect of core superfluidity on the braking index. Our results show conclusively that, within the model used in this work, any significant deviation of the braking index away from the value n =3 occurs at frequencies higher than about ten times the frequency of the slow rotating isolated pulsars most accurately measured to date. The rate of change of n with frequency is related to the softness of the EoS and the MB of the star as this controls the degree of departure from sphericity. Change in the moment of inertia in the MDR model alone, even with the more realistic features considered here, cannot explain the observational data on the braking index and other mechanisms have to be sought.

Hamil, O.; Stone, J. R.; Urbanec, M.; Urbancová, G.

2015-03-01

411

Characterization of Pathogenic Vibrio parahaemolyticus Isolates from Clinical Sources in Spain and Comparison with Asian and North American Pandemic Isolates  

PubMed Central

In spite of the potential risk involved with contamination of seafood with Vibrio parahaemolyticus, there is a lack of information on the occurrence of pathogenic V. parahaemolyticus in Europe. This organism was isolated in 1999 from a large outbreak (64 cases admitted to a single hospital) associated with raw oyster consumption in Galicia, Spain, one of the most important regions in shellfish production worldwide. Two V. parahaemolyticus isolates from the 1999 Galicia outbreak, three additional clinical isolates obtained in the same period from hospitals in Spain, two reference strains from clinical sources, and five Spanish environmental isolates were examined. Seventeen isolates belonging to the pandemic clone isolated in Asia and North America were included in the study for comparison. All isolates were characterized by serotyping, PCR for virulence-related genes, pulsed-field gel electrophoresis (PFGE), and plasmid analysis. Four of the five clinical isolates from hospitals in Spain belonged to serotype O4:K11; the remaining isolate was O4:K untypeable (KUT). All five isolates were positive for V. parahaemolyticus toxR and tlh (species-specific genes) and tdh and negative for trh and group-specific PCR (a PCR method for detection of the pandemic clone). PFGE analysis with NotI and SfiI discriminated the European isolates in two closely related PFGE types included in a homogeneous cluster, clearly differentiated from the Asian and North American isolates. The five environmental isolates belonged to serotypes O2:K28, O2:KUT, O3:K53, O4:KUT, and O8:K22 and were negative for all virulence genes. The five isolates were discriminated into five different PFGE types unrelated to any other isolate included in the study. While the virulence characteristics (tdh positive, trh negative) of the Spanish clinical isolates matched those of the O3:K6 clone from Asia and North America, they were clearly excluded from this clone by group-specific PCR, PFGE, and serotyping. The results of this study suggest that a unique and specific clone could be related to the V. parahaemolyticus infections in Europe. PMID:15472326

Martinez-Urtaza, Jaime; Lozano-Leon, Antonio; DePaola, Angelo; Ishibashi, Masanori; Shimada, Kanae; Nishibuchi, Mitsuaki; Liebana, Ernesto

2004-01-01

412

The First Macrolide-Resistant Bordetella pertussis Strains Isolated From Iranian Patients  

PubMed Central

Background: Whooping cough was considered as one of the major causes of childhood morbidity and mortality worldwide. Resistant isolates of Bordetella pertussis to macrolides in some countries have been recently reported. Objectives: Recent reports on macrolide-resistant B. pertussis isolates and lack of evidence for such resistance in clinical isolates of the Iranian patients led the authors of the current study to study antibiotic susceptibility of the collected isolates in the country. Susceptibility of the B. pertussis isolates to three antibiotics was studied. Relatedness of the strains recovered in this research was also examined. Materials and Methods: The antibacterial activities of erythromycin, azithromycin, and clarithromycin antibiotics against the recovered isolates of 779 nasopharyngeal swabs were examined using MIC (Minimum Inhibitory Concentration) method. Relationship of the strains was characterized by Pulsed-field Gel Electrophoresis (PFGE). Results: Among the specimens, 11 cases (1.4%) were culture-positive. Among these isolates, only two isolates had high MIC values for erythromycin and clarithromycin. Pulsed-field gel electrophoresis analysis of the isolates revealed 6 PFGE profiles (A-F) among which three and two isolates had the same patterns in profiles A and B, respectively. Conclusions: Azithromycin can be a good drug of choice to treat patients infected by B. pertussis in Iran. Clonal relationship of the isolates showed that the same B. pertussis strains were isolated from different patients in Iran. PMID:25371806

Shahcheraghi, Fereshteh; Nakhost Lotfi, Masoumeh; Nikbin, Vajiheh Sadat; Shooraj, Fahimeh; Azizian, Reza; Parzadeh, Masoumeh; Allahyar Torkaman, Mohammad Reza; Zahraei, Seyed Mohsen

2014-01-01

413

Isolation mounts scatterometry with RCWA and PML  

NASA Astrophysics Data System (ADS)

In this paper, we examine the sensitivity of scatterometry for the isolation mounts on the substrate by applying PML in RCWA. We analyze the reflectance from the silicon and resist single mount and the silicon double mounts on the silicon substrate. First, we investigate the mode convergences and the beam width dependences of reflectance. Second, we show the propagation properties of the electromagnetic fields propagating for the isolation mounts on the silicon substrate. Finally, we examine the wavelength properties of reflectance calculated by changing the beam width, the mount width and the mount height for single mount and the silicon mount positions for the double silicon mounts. Then, we understand that the scatterometry observation is possible in several decade microns beam width.

Shirasaki, Hirokimi

2014-04-01

414

Isolated resonator gyroscope with isolation trimming using a secondary element  

NASA Technical Reports Server (NTRS)

The present invention discloses a resonator gyroscope including an isolated resonator. One or more flexures support the isolated resonator and a baseplate is affixed to the resonator by the flexures. Drive and sense elements are affixed to the baseplate and used to excite the resonator and sense movement of the gyroscope. In addition, at least one secondary element (e.g., another electrode) is affixed to the baseplate and used for trimming isolation of the resonator. The resonator operates such that it transfers substantially no net momentum to the baseplate when the resonator is excited. Typically, the isolated resonator comprises a proof mass and a counterbalancing plate.

Challoner, A. Dorian (Inventor); Shcheglov, Kirill V. (Inventor)

2006-01-01

415

The neuroendocrinology of social isolation.  

PubMed

Social isolation has been recognized as a major risk factor for morbidity and mortality in humans for more than a quarter of a century. Although the focus of research has been on objective social roles and health behavior, the brain is the key organ for forming, monitoring, maintaining, repairing, and replacing salutary connections with others. Accordingly, population-based longitudinal research indicates that perceived social isolation (loneliness) is a risk factor for morbidity and mortality independent of objective social isolation and health behavior. Human and animal investigations of neuroendocrine stress mechanisms that may be involved suggest that (a) chronic social isolation increases the activation of the hypothalamic pituitary adrenocortical axis, and (b) these effects are more dependent on the disruption of a social bond between a significant pair than objective isolation per se. The relational factors and neuroendocrine, neurobiological, and genetic mechanisms that may contribute to the association between perceived isolation and mortality are reviewed. PMID:25148851

Cacioppo, John T; Cacioppo, Stephanie; Capitanio, John P; Cole, Steven W

2015-01-01

416

On Gravitational anomaly and Hawking radiation near weakly isolated horizon  

E-print Network

Based on the idea of the work by Wilczek and his collaborators, we consider the gravitational anomaly near weekly isolated horizon. We find that there exists a universal choice of tortoise coordinate for any weakly isolated horizon. Under this coordinate, the leading behavior of a quite arbitrary scalar field near horizon is a 2-dimensional chiral scalar field. This means we can extend the idea of Wilczek and his collaborators to more general cases and show the relation between gravitational anomaly and Hawking radiation is a universal property of black hole horizon.

Xiaoning Wu; Chao-Guang Huang; Jia-Rui Sun

2008-01-09

417

Material isolation enclosure  

DOEpatents

An enclosure similar to a glovebox for isolating materials from the atmosphere, yet allowing a technician to manipulate the materials and also apparatus which is located inside the enclosure. A portion of a wall of the enclosure is comprised of at least one flexible curtain. An opening defined by a frame is provided for the technician to insert his hands and forearms into the enclosure. The frame is movable in one plane, so that the technician has access to substantially all of the working interior of the enclosure. As the frame is moved by the technician, while he accomplishes work inside the enclosure, the curtain moves such that the only opening through the enclosure wall is the frame. In a preferred embodiment, where a negative pressure is maintained inside the enclosure, the frame is comprised of airfoils so that turbulence is reduced, thereby enhancing material retention within the box.

Martell, Calvin J. (Los Alamos, NM); Dahlby, Joel W. (Los Alamos, NM); Gallimore, Bradford F. (Los Alamos, NM); Comer, Bob E. (Versailles, MO); Stone, Water A. (Los Alamos, NM); Carlson, David O. (Tesugue, NM)

1993-01-01

418

Positive isolation disconnect  

NASA Technical Reports Server (NTRS)

A disconnect composed basically of two halves each consisting of a poppet valve operable to isolate fluid with essentially zero fluid loss is presented. The two halves are coupled together by a quickly releasable coupling which may be either a coupling ring tightened or loosened by a twisting motion, or a clamp operated by a pivoted to prevent disconnecting the two halves until both valves are in closed condition. The positive feature of the device is one requiring a valve closing step before a disconnect step, and takes structural form in an accentric lobe mounted on the valve operating stem. If some obstruction prevents the poppet from moving to its seat, the eccentric lobe cannot be rotated to the closed position, and the interlock prevents a disconnect.

Friedell, M. V. (invento)

1978-01-01

419

Material isolation enclosure  

DOEpatents

An enclosure is described, similar to a glove box, for isolating materials from the atmosphere, yet allowing a technician to manipulate the materials and also apparatus which is located inside the enclosure. A portion of a wall of the enclosure is comprised of at least one flexible curtain. An opening defined by a frame is provided for the technician to insert his hands and forearms into the enclosure. The frame is movable in one plane, so that the technician has access to substantially all of the working interior of the enclosure. As the frame is moved by the technician, while he accomplishes work inside the enclosure, the curtain moves such that the only opening through the enclosure wall is the frame. In a preferred embodiment, where a negative pressure is maintained inside the enclosure, the frame is comprised of airfoils so that turbulence is reduced, thereby enhancing material retention within the box.

Martell, C.J.; Dahlby, J.W.; Gallimore, B.F.; Comer, B.E.; Stone, W.A.; Carlson, D.O.

1993-04-27

420

Associations between the Genotypes of Staphylococcus aureus Bloodstream Isolates and Clinical Characteristics and Outcomes of Bacteremic Patients  

Microsoft Academic Search

We investigated associations between the genotypic and phenotypic features of Staphylococcus aureus blood- stream isolates and the clinical characteristics of bacteremic patients enrolled in a phase III trial of S. aureus bacteremia and endocarditis. Isolates underwent pulsed-field gel electrophoresis, PCR for 33 putative virulence genes, and screening for heteroresistant glycopeptide intermediate S. aureus (hGISA). A total of 230 isolates (141

Tahaniyat Lalani; Jerome J. Federspiel; Helen W. Boucher; Thomas H. Rude; In-Gyu Bae; Michael J. Rybak; Giang T. Tonthat; G. Ralph Corey; Martin E. Stryjewski; George Sakoulas; Vivian H. Chu; Jeff Alder; Judith N. Steenbergen; Steven A. Luperchio; Marilyn Campion; Christopher W. Woods; Vance G. Fowler

421

Terahertz isolator based on nonreciprocal magneto-metasurface.  

PubMed

A magneto-metasurface with nonreciprocal terahertz (THz) transmission has been proposed to form a THz isolator. Importantly, we have discussed the two necessary conditions for THz nonreciprocal transmission in the metasurface: (1) There should be magneto-optical responses for THz waves in the metasurface; (2) The transmission system of the metasurface needs to be asymmetric for forward and backward waves. These two conditions lead to the time reversal symmetry breaking of system, and the magnetoplasmon mode splitting and nonreciprocal resonance enhancement can be observed in the asymmetry magneto-metasurface. Moreover, the isolation dependences and tunability on the external magnetic field and temperature have also been investigated, which shows that the best operating state with a high isolation can be designed. The numerical simulations show a maximum isolation of 43 dB and a 10 dB operating bandwidth of 20 GHz under an external magnetic field of 0.3 T, and the insertion loss is smaller than 1.79 dB. This low-loss, high isolation, easy coupling THz isolator has broadly potentials for THz application systems. PMID:25835861

Chen, Sai; Fan, Fei; Wang, Xianghui; Wu, Pengfei; Zhang, Hui; Chang, Shengjiang

2015-01-26

422

Controlling quantum critical dynamics of isolated systems  

NASA Astrophysics Data System (ADS)

Controlling the non adiabatic dynamics of isolated quantum systems driven through a critical point is of interest in a variety of fields ranging from quantum simulation to finite-time thermodynamics. We briefly review the different methods for designing protocols which minimize excitation (defect) production in a closed quantum critical system driven out of equilibrium. We chart out the role of specific driving schemes for this procedure, point out their experimental relevance, and discuss their implementation in the context of ultracold atom and spin systems.

del Campo, A.; Sengupta, K.

2015-02-01

423