40 CFR 165.43 - Scope of pesticide products included.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., fungi, protozoa, algae, or slime; and (B) In the intended use is subject to a tolerance under section... from contamination, fouling, or deterioration caused by bacteria, viruses, fungi, protozoa, algae, or...

40 CFR 165.43 - Scope of pesticide products included.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., fungi, protozoa, algae, or slime; and (B) In the intended use is subject to a tolerance under section... from contamination, fouling, or deterioration caused by bacteria, viruses, fungi, protozoa, algae, or...

40 CFR 165.63 - Scope of pesticide products included.

Code of Federal Regulations, 2011 CFR

2011-07-01

... caused by bacteria, viruses, fungi, protozoa, algae, or slime; and (B) In the intended use is subject to... bacteria, viruses, fungi, protozoa, algae, or slime. (ii) The labeling of the pesticide product includes...

40 CFR 165.63 - Scope of pesticide products included.

Code of Federal Regulations, 2014 CFR

2014-07-01

... caused by bacteria, viruses, fungi, protozoa, algae, or slime; and (B) In the intended use is subject to... bacteria, viruses, fungi, protozoa, algae, or slime. (ii) The labeling of the pesticide product includes...

40 CFR 165.63 - Scope of pesticide products included.

Code of Federal Regulations, 2013 CFR

2013-07-01

... caused by bacteria, viruses, fungi, protozoa, algae, or slime; and (B) In the intended use is subject to... bacteria, viruses, fungi, protozoa, algae, or slime. (ii) The labeling of the pesticide product includes...

40 CFR 165.63 - Scope of pesticide products included.

Code of Federal Regulations, 2012 CFR

2012-07-01

... caused by bacteria, viruses, fungi, protozoa, algae, or slime; and (B) In the intended use is subject to... bacteria, viruses, fungi, protozoa, algae, or slime. (ii) The labeling of the pesticide product includes...

Newer diagnostic approaches to intestinal protozoa.

PubMed

van Lieshout, Lisette; Verweij, Jaco J

2010-10-01

To update the reader on the latest developments in the laboratory diagnosis of intestinal protozoa. Correct identification of a diarrhoea causing pathogens is essential for the choice of treatment in an individual patient as well as to map the aetiology of diarrhoea in a variety of patient populations. Classical diagnosis of diarrhoea causing protozoa by microscopic examination of a stool sample lacks both sensitivity and specificity. Alternative diagnostic platforms are discussed. Recent literature on the diagnosis of intestinal protozoa has focused mainly on nucleic acid-based assays, in particular the specific detection of parasite DNA in stool samples using real-time PCR. In addition, the trend has been moving from single pathogen detection to a multiplex approach, allowing simultaneous identification of multiple parasites. Different combinations of targets can be used within a routine diagnostic setting, depending on the patient population, such as children, immunocompromised individuals and those who have been travelling to tropical regions. Large-scale monitoring and evaluation of control strategies become feasible due to automation and high-throughput facilities. Improved technology also has become available for differentiating protozoa subspecies, which facilitates outbreak investigations and extensive research in molecular epidemiology.

Use of a novel continuous culture fermentor system for in vitro determination of enteric methane output from ruminants

USDA-ARS?s Scientific Manuscript database

Continuous culture fermentor systems (CCFS) serve to evaluate the effect of diet on in vitro nutrient digestibility, fermentation, and microbial protein synthesis. Limitations of CCFS are: maintaining protozoa populations, and avoiding accumulation of undigested material in the vessels. Therefore, a...

Intestinal protozoa in HIV-infected patients in Apulia, South Italy.

PubMed Central

Brandonisio, O.; Maggi, P.; Panaro, M. A.; Lisi, S.; Andriola, A.; Acquafredda, A.; Angarano, G.

1999-01-01

Protozoa are important enteric pathogens in patients with human immunodeficiency virus (HIV) infection. In this study the prevalence of intestinal protozoa in 154 HIV-infected patients, with or without diarrhoea, in our region (Apulia, South Italy) was evaluated between December 1993 and February 1998. In the majority of patients CD4+ T cell count was below 200/microl. The overall prevalence of intestinal protozoa was 43/154 (27.92%). Twenty-eight (43.08%) out of 65 patients with diarrhoea and 15 (16-85%) out of 89 non-diarrhoeic patients were parasitized. In particular, in the group of 65 patients with diarrhoea the following protozoa were identified: Cryptosporidium parvum in 14 (21.54%), Blastocystis hominis in 7 (10.77%), microsporidia in 6 (9.23%), Giardia lamblia in 4 (6.15%) and Isospora belli in 1 (1.54%). Three patients were Cryptosporidium parvum-microsporidia co-infected. In patients without intestinal symptoms, prevalence was 3/89 (3.37%) for Cryptosporidium parvum, 9/89 (10.11%) for Blastocystis hominis, 1/89 (1.12%) for microsporidia and 2/89 (2.25%) for Giardia lamblia. A significant (P<0.001) correlation was observed between protozoan infection and the presence of diarrhoea. In particular, Cryptosporidium parvum and microsporidia infections were significantly (P<0.001) and P = 0.046, respectively) associated with diarrhoeal illness. Moreover, the majority of cases of cryptosporidiosis were first diagnosed in the periods of heaviest rainfall. Therefore, drinking water contamination may be a possible source of human infection in our area. PMID:10694157

THE PERSISTENCE OF NONTUBERCULOUS MYCOBACTERIA INI A DRINKING WATER DISTRIBUTION SYSTEM AFTER THE ADDITION OF FILTRATION TREATMENT

EPA Science Inventory

There is evidence that drinking water may be a source of pathogenic nontuberculous mycobacteria (NTM) infections in humans. One method by which NTM are believed to enter drinking water distribution systems is by their intracellular colonization of protozoa. Our goal was to determ...

THE PERSISTENCE OF MYCOBACTERIUM AVIUM IN A DRINKING WATER DISTRIBUTION SYSTEM AFTER THE ADDITION OF FILTRATION TREATMENT

EPA Science Inventory

There is evidence that drinking water may be a source of pathogenic nontuberculous mycobacteria (NTM) infections in humans. One method by which NTM are believed to enter drinking water distribution systems is by their intracellular location within protozoa. Our goal was to determ...

[Contamination of protozoa by enteroviruses in fresh water and sewages].

PubMed

Skachkov, M V; Al'misheva, A Sh; Plotnikov, A O; Nemtseva, N V; Skvortsov, V O

2009-01-01

To determine rate of infection of protozoa by enteroviruses to assess the potential role of protozoa as a natural reservoir of enteroviruses. The samples were collected from flowing and stagnant water reservoirs in Orenburg region in summer and autumn. The samples of sewages were taken in all stages of their treatment. Cultures of protozoa were isolated with micromanipulator equipped with micropipette, incubated on Pratt's medium at 25 degrees C and fed with Pseudomonas fluorescens culture. RNA of enteroviruses was detected by reverse transcription polymerase chain reaction (RT-PCR). Seventy-two protozoan species were found in Ural river, whereas 15 and 38 species were found in lakes and sewages respectively. Enteroviruses were detected by RT-PCR in 61.8% cultures of protozoa belonging to 23 species of flagellates, amoebae and ciliates isolated from natural water bodies undergoing anthropogenic impact as well as from sewages in all stages of their treatment. Predominant localization of enteroviruses in dominant taxons of protozoa (Paraphysomonas sp., Spumella sp., Petalomonas poosilla, Amoeba sp.) was noted. Obtained data confirm presence of enteroviruses in protozoa living both in flowing and stagnant recreation natural water bodies as well as in sewages and confirm the hypothesis of persistence of enteroviruses in protozoa and the reservoir role of the latter. Contingency of life cycles of viruses and protozoa allows to explain the seasonality of aseptic meningitis incidence caused by enteroviruses, which peaks in summer and autumn when protozoa massively multiply in water bodies.

Putative bronchopulmonary flagellated protozoa in immunosuppressed patients.

PubMed

Kilimcioglu, Ali Ahmet; Havlucu, Yavuz; Girginkardesler, Nogay; Celik, Pınar; Yereli, Kor; Özbilgin, Ahmet

2014-01-01

Flagellated protozoa that cause bronchopulmonary symptoms in humans are commonly neglected. These protozoal forms which were presumed to be "flagellated protozoa" have been previously identified in immunosuppressed patients in a number of studies, but have not been certainly classified so far. Since no human cases of bronchopulmonary flagellated protozoa were reported from Turkey, we aimed to investigate these putative protozoa in immunosuppressed patients who are particularly at risk of infectious diseases. Bronchoalveolar lavage fluid samples of 110 immunosuppressed adult patients who were admitted to the Department of Chest Diseases, Hafsa Sultan Hospital of Celal Bayar University, Manisa, Turkey, were examined in terms of parasites by light microscopy. Flagellated protozoal forms were detected in nine (8.2%) of 110 cases. Metronidazole (500 mg b.i.d. for 30 days) was given to all positive cases and a second bronchoscopy was performed at the end of the treatment, which revealed no parasites. In conclusion, immunosuppressed patients with bronchopulmonary symptoms should attentively be examined with regard to flagellated protozoa which can easily be misidentified as epithelial cells.

Molecular Analysis of the Enteric Protozoa Associated with Acute Diarrhea in Hospitalized Children.

PubMed

Boughattas, Sonia; Behnke, Jerzy M; Al-Ansari, Khalid; Sharma, Aarti; Abu-Alainin, Wafa; Al-Thani, Asma; Abu-Madi, Marawan A

2017-01-01

Pediatric diarrhea is a common cause of death among children under 5 years of age. In the current study, we investigated the frequency of intestinal parasites among 580 pediatric patients with chronic diarrhea. Parasitic protozoa (all species combined) were detected by molecular tools in 22.9% of the children and the most common parasite was Cryptosporidium spp. (15.1%). Blastocystis hominis was detected in 4.7%, Dientamoeba fragilis in 4%, Giardia duodenalis in 1.7%, and Entamoeba histolytica in 0.17%. Protozoan infections were observed among all regional groups, but prevalence was highest among Qatari subjects and during the winter season. Typing of Cryptosporidium spp. revealed a predominance of Cryptosporidium parvum in 92% of cases with mostly the IIdA20G1 subtype. Subtypes IIdA19G2, IIdA18G2, IIdA18G1, IIdA17G1, IIdA16G1, and IIdA14G1 were also detected. For Cryptosporidium hominis , IbA10G2 and IbA9G3 subtypes were identified. This study provides supplementary information for implementing prevention and control strategies to reduce the burden of these pediatric protozoan infections. Further analyses are required to better understand the local epidemiology and transmission of Cryptosporidium spp. in Qatar.

Protozoan Parasites in Drinking Water: A System Approach for Improved Water, Sanitation and Hygiene in Developing Countries

PubMed Central

Tussupova, Kamshat; Berndtsson, Ronny; Sharapatova, Kulyash

2018-01-01

Improved water, sanitation and hygiene (WASH) are significant in preventing diarrhea morbidity and mortality caused by protozoa in low- and middle-income countries. Due to the intimate and complex relationships between the different WASH components, it is often necessary to improve not just one but all of these components to have sustainable results. The objective of this paper was to review the current state of WASH-related health problems caused by parasitic protozoa by: giving an overview and classification of protozoa and their effect on people’s health, discussing different ways to improve accessibility to safe drinking water, sanitation services and personal hygiene behavior; and suggesting an institutional approach to ensure improved WASH. The findings indicate that Giardia and Cryptosporidium are more often identified during waterborne or water-washed outbreaks and they are less sensitive than most of the bacteria and viruses to conventional drinking water and wastewater treatment methods. There are various institutions of control and prevention of water-related diseases caused by protozoa in developed countries. Unfortunately, the developing regions do not have comparable systems. Consequently, the institutional and systems approach to WASH is necessary in these countries. PMID:29534511

Protozoan Parasites in Drinking Water: A System Approach for Improved Water, Sanitation and Hygiene in Developing Countries.

PubMed

Omarova, Alua; Tussupova, Kamshat; Berndtsson, Ronny; Kalishev, Marat; Sharapatova, Kulyash

2018-03-12

Improved water, sanitation and hygiene (WASH) are significant in preventing diarrhea morbidity and mortality caused by protozoa in low- and middle-income countries. Due to the intimate and complex relationships between the different WASH components, it is often necessary to improve not just one but all of these components to have sustainable results. The objective of this paper was to review the current state of WASH-related health problems caused by parasitic protozoa by: giving an overview and classification of protozoa and their effect on people's health, discussing different ways to improve accessibility to safe drinking water, sanitation services and personal hygiene behavior; and suggesting an institutional approach to ensure improved WASH. The findings indicate that Giardia and Cryptosporidium are more often identified during waterborne or water-washed outbreaks and they are less sensitive than most of the bacteria and viruses to conventional drinking water and wastewater treatment methods. There are various institutions of control and prevention of water-related diseases caused by protozoa in developed countries. Unfortunately, the developing regions do not have comparable systems. Consequently, the institutional and systems approach to WASH is necessary in these countries.

Prevalence, Risk Factors, and Outcomes of Irritable Bowel Syndrome After Infectious Enteritis: a Systematic Review and Meta-analysis

PubMed Central

Klem, Fabiane; Wadhwa, Akhilesh; Prokop, Larry; Sundt, Wendy; Farrugia, Gianrico; Camilleri, Michael; Singh, Siddharth; Grover, Madhusudan

2017-01-01

Background & Aims Foodborne illness affects 15% of the United States population each year and is a risk factor for irritable bowel syndrome (IBS). We evaluated risk of, risk factors for, and outcomes of IBS after infectious enteritis Methods We performed a systematic review of electronic databases from 1994 through August 31, 2015 to identify cohort studies of the prevalence of IBS 3 months or more after infectious enteritis. We used random effects meta-analysis to calculate the summary point prevalence of IBS after infectious enteritis, as well as relative risk (compared to individuals without infectious enteritis) and host- and enteritis-related risk factors. Results We identified 45 studies, comprising 21,421 individuals with enteritis, followed for 3 months–10 years for development of IBS. The pooled prevalence of IBS at 12 months after infectious enteritis was 10.1% (95% CI, 7.2–14.1) and at more than 12 months after infectious enteritis was 14.5% (95% CI, 7.7–25.5). Risk of IBS was 4.2-fold higher in patients who had infectious enteritis in the past 12 months than in individuals in those who had not (95% CI, 3.1–5.7); risk of IBS was 2.3-fold higher in individuals who had infectious enteritis longer than 12 months ago than in individuals who had not (95% CI, 1.8–3.0). Of patients with enteritis caused by protozoa or parasites, 41.9% developed IBS; of patients with enteritis caused bacterial infection, 13.8% developed IBS. Risk of IBS was significantly increased in women (odds ratio [OR], 2.2; 95% CI, 1.6–3.1) and with antibiotic exposure (OR, 1.7; 95% CI, 1.2–2.4), anxiety (OR, 2; 95% CI, 1.3–2.9), depression (OR, 1.5; 95% CI, 1.2–1.9), somatization (OR, 4.1; 95% CI, 2.7–6.0), neuroticism (OR, 3.3; 95% CI, 1.6–6.5), and clinical indicators of enteritis severity. There was a considerable level of heterogeneity among studies. Conclusion In a systematic review and meta-analysis, we found more than 10% of patients with infectious enteritis to later develop IBS; risk of IBS was 4-fold higher than in individuals who did not have infectious enteritis, although there was heterogeneity among studies analyzed. Women—particularly those with severe enteritis—are at increased risk for developing IBS, as are individuals with psychological distress and users of antibiotics during the enteritis. PMID:28069350

Protozoacidal Trojan-Horse: use of a ligand-lytic peptide for selective destruction of symbiotic protozoa within termite guts.

PubMed

Sethi, Amit; Delatte, Jennifer; Foil, Lane; Husseneder, Claudia

2014-01-01

For novel biotechnology-based termite control, we developed a cellulose bait containing freeze-dried genetically engineered yeast which expresses a protozoacidal lytic peptide attached to a protozoa-recognizing ligand. The yeast acts as a 'Trojan-Horse' that kills the cellulose-digesting protozoa in the termite gut, which leads to the death of termites, presumably due to inefficient cellulose digestion. The ligand targets the lytic peptide specifically to protozoa, thereby increasing its protozoacidal efficiency while protecting non-target organisms. After ingestion of the bait, the yeast propagates in the termite's gut and is spread throughout the termite colony via social interactions. This novel paratransgenesis-based strategy could be a good supplement for current termite control using fortified biological control agents in addition to chemical insecticides. Moreover, this ligand-lytic peptide system could be used for drug development to selectively target disease-causing protozoa in humans or other vertebrates.

Protozoacidal Trojan-Horse: Use of a Ligand-Lytic Peptide for Selective Destruction of Symbiotic Protozoa within Termite Guts

PubMed Central

Sethi, Amit; Delatte, Jennifer; Foil, Lane; Husseneder, Claudia

2014-01-01

For novel biotechnology-based termite control, we developed a cellulose bait containing freeze-dried genetically engineered yeast which expresses a protozoacidal lytic peptide attached to a protozoa-recognizing ligand. The yeast acts as a ‘Trojan-Horse’ that kills the cellulose-digesting protozoa in the termite gut, which leads to the death of termites, presumably due to inefficient cellulose digestion. The ligand targets the lytic peptide specifically to protozoa, thereby increasing its protozoacidal efficiency while protecting non-target organisms. After ingestion of the bait, the yeast propagates in the termite's gut and is spread throughout the termite colony via social interactions. This novel paratransgenesis-based strategy could be a good supplement for current termite control using fortified biological control agents in addition to chemical insecticides. Moreover, this ligand-lytic peptide system could be used for drug development to selectively target disease-causing protozoa in humans or other vertebrates. PMID:25198727

THE IMPORTANCE OF ANIMAL INFECTIONS FOR THE HUMAN

DTIC Science & Technology

tuberculosis, leptospiroses. VIRUS-CAUSED ZOOANTHROPONOSES: Rickettsioses, ornithosis, lyssa, arboviroses. FUNGUS-CAUSED ANIMAL-HUMAN INFECTIONS: filamentous fungus, yeast fungus. PROTOZOA DISEASES: Toxoplasmoses .

[The experimental evaluation of the possibility of the penetration of enteric viruses from the surface into the pulp of contaminated fruits and vegetables].

PubMed

Sergevnin, V I; Ladeyshchikova, Yu I; Sarmometov, E V; Podgorunskaya, I L; Kudrevatykh, E V

2014-01-01

According to the results of complex microbiological examination of samples of vegetables, fruits and grapes there was established significant contamination of them with opportunistic bacteria, antigens of intestinal viruses and cysts of intestinal Protozoa, that confirms the epidemiological role of these products as factors in transmission of acute intestinal infections. There was revealed ribonucleic acid of enteric viruses in experimentally infected pulp from the surface of tomatoes and apples, that indicates to the possibility of penetration of these pathogens into the fruits and vegetables through intact (having no visible damages) surface.

Putative Bronchopulmonary Flagellated Protozoa in Immunosuppressed Patients

PubMed Central

Kilimcioglu, Ali Ahmet; Havlucu, Yavuz; Çelik, Pınar; Özbilgin, Ahmet

2014-01-01

Flagellated protozoa that cause bronchopulmonary symptoms in humans are commonly neglected. These protozoal forms which were presumed to be “flagellated protozoa” have been previously identified in immunosuppressed patients in a number of studies, but have not been certainly classified so far. Since no human cases of bronchopulmonary flagellated protozoa were reported from Turkey, we aimed to investigate these putative protozoa in immunosuppressed patients who are particularly at risk of infectious diseases. Bronchoalveolar lavage fluid samples of 110 immunosuppressed adult patients who were admitted to the Department of Chest Diseases, Hafsa Sultan Hospital of Celal Bayar University, Manisa, Turkey, were examined in terms of parasites by light microscopy. Flagellated protozoal forms were detected in nine (8.2%) of 110 cases. Metronidazole (500 mg b.i.d. for 30 days) was given to all positive cases and a second bronchoscopy was performed at the end of the treatment, which revealed no parasites. In conclusion, immunosuppressed patients with bronchopulmonary symptoms should attentively be examined with regard to flagellated protozoa which can easily be misidentified as epithelial cells. PMID:24804259

Water-borne protozoa parasites: The Latin American perspective.

PubMed

Rosado-García, Félix Manuel; Guerrero-Flórez, Milena; Karanis, Gabriele; Hinojosa, María Del Carmen; Karanis, Panagiotis

2017-07-01

Health systems, sanitation and water access have certain limitations in nations of Latin America (LA): typical matters of developing countries. Water is often contaminated and therefore unhealthy for the consumers and users. Information on prevalence and detection of waterborne parasitic protozoa are limited or not available in LA. Only few reports have documented in this field during the last forty years and Brazil leads the list, including countries in South America and Mexico within Central America region and Caribbean islands. From 1979 to 2015, 16 outbreaks of waterborne-protozoa, were reported in Latin American countries. T. gondii and C. cayetanensis were the protozoa, which caused more outbreaks and Giardia spp. and Cryptosporidium spp. were the most frequently found protozoa in water samples. On the other hand, Latin America countries have not got a coherent methodology for detection of protozoa in water samples despite whole LA is highly vulnerable to extreme weather events related to waterborne-infections; although Brazil and Colombia have some implemented laws in their surveillance systems. It would be important to coordinate all surveillance systems in between all countries for early detection and measures against waterborne-protozoan and to establish effective and suitable diagnosis tools according to the country's economic strength and particular needs. Copyright © 2017 Elsevier GmbH. All rights reserved.

Foodborne intestinal protozoan infection and associated factors among patients with watery diarrhea in Northern Ethiopia; a cross-sectional study.

PubMed

Berhe, Birhane; Bugssa, Gessessew; Bayisa, Sena; Alemu, Megbaru

2018-03-02

Intestinal protozoa are parasites transmitted by consumption of contaminated water and food and mainly affect children and elder people and cause considerable health problems. They are the leading causes of outpatient morbidity due to diarrhea in the developing countries. So, assessing water and food source of diarrheal patients and identifying the main associated factors for transmission of protozoan parasitic infections help for effective control measures of protozoan infections. Hence, the current study was aimed at determining the prevalence of foodborne intestinal protozoa infections and associated factors among diarrheic patients in North Ethiopia. A health facility based cross-sectional study was conducted among 223 patients with watery diarrhea in four selected government health facilities in North Ethiopia from November 2016-June 2017. A structured questionnaire was used to collect data on socio-demography of study participants and factors associated with foodborne protozoa infections. The diarrheic stool samples were collected, transported, and processed using direct wet mount, formal-ether concentration and modified ZiehlNeelson staining methods. The data were analyzed using SPSS version 21 and descriptive statistics, bi-variate, and multivariate logistic regressions were computed. P-value < 0.05 at 95% confidence interval was considered statistically significant. The overall prevalence of foodborne protozoa infection was 101 (45.3%). The predominant protozoa species identified was Entamoeba histolytica/dispar 55 (24.7%), followed by Giardia intestinalis 25 (11.2%) and Cryptosporidium species 5 (2.2%). The highest proportion of protozoa infection was observed among males (23.3%) and the age group 15-24 years (13.5%). Statistically significant associations were observed between foodborne protozoan infection and not using any type of recipe to decontaminate salads and fruits (AOR = 2.64, 95 CI: 1.34-5.19, P = 0.005) and using vinegar as a decontaminant (AOR = 2.83, 95 CI: 1.24-6.48, P = 0.014). Eating out (meals at a restaurant) on the other hand was found to be protective for foodborne protozoan infection (AOR = 0.43, 95 CI: 0.23-0.78, P = 0.006). Our study revealed that foodborne protozoa infections are of public health significance in the study area. Vinegar, which is frequently used as a recipe for decontaminating salads and fruits, is inversely related to foodborne protozoa parasite infection .

Improved method for concentration of Giardia, Cryptosporidium, and poliovirus from water.

PubMed

Watt, Pamela M; Johnson, Dana C; Gerba, Charles P

2002-03-01

Methods for the concentration of enteric viruses and the protozoan parasites, Giardia and Cryptosporidium, from drinking water currently require the use of two different types of filters. Electropositive or electronegative microporous filters (0.2-0.45 microm nominal porosity) are used for the collection of enteroviruses, while polypropylene spun-fiber filters (1 microm porosity) and small pleated cartridge filters are used for the collection of protozoan parasites from water. Since the filter mechanically traps the protozoa by size exclusion, a microporous filter with an appropriately small nominal porosity could possibly be used for co-collection of both protozoa and enteroviruses. This study compared the concentration efficiencies of a polypropylene fiber cartridge (DPPPY) filter and two different microporous filters (Filterite and IMDS) with poliovirus (type 1), with respect to their ability to concentrate Giardia and Cryptosporidium from water. Giardia cysts and Cryptosporidium oocysts were added to 4001 of either tap water or tertiary treated wastewater and passed through the test filter. The protozoa were eluted from the polypropylene filter by hand-washing in a detergent solution. Viruses and protozoa were eluted from the microporous filter by two consecutive back-washes with a 1.5% beef extract, 0.1% Tween 80 solution. The eluent was then centrifuged to remove the parasites and the supernatant assayed for viruses. The overall efficiency was greater for the Filterite filter (40.4% for Giardia; 36.6% for Cryptosporidium) when compared to the spun fiber filter (10.1% for Giardia; 16.0% for Cryptosporidium). The Filterite filters were easier and faster to process than the polypropylene spun fiber filters. There was no significant difference in the recovery of protozoa from 1MDS and DPPPY filters. Co-collection of viruses and protozoan parasites from water onto the same filter is possible and can reduce the time and cost of routine water monitoring.

Surveillance for Enteric Pathogens in a Case-Control Study of Acute Diarrhea in Western Kenya

DTIC Science & Technology

2012-11-01

isolates was ascertained using the MicroScan WalkAway 40 Plus. An enzyme immunoassay kit was used to detect rotavirus , and ova and parasite...examination was conducted by micros- copy and an enzyme immunoassay. Results: Rotavirus (10.2% and 10.5%) and Shigella (11% and 8%) were isolated significantly...Keywords: Gastroenteritis, Protozoa, Rotavirus , Shigella, Escherichia coli, Antimicrobial resistance Introduction Diarrheal disease continues to be a

Bronchopulmonary Disease Caused by Flagellated Protozoa Infection in 15 Chinese Children.

PubMed

Liu, Jinrong; Li, Shaogang; Li, Huimin; Fan, Yimu; Yang, Haiming; Xu, Hui; Shen, Yuelin; Zhao, Shunying

2017-04-01

Bronchopulmonary disease caused by flagellated protozoa infection (BPFP) is thought to be rare in children but may be an emerging or underestimated disease, especially in developing countries. In this study, we retrospectively reviewed records of 15 patients who were presented with a cough, wheezing or bronchopulmonary disease of unknown causes during admission, and patients who were finally diagnosed with BPFP from January 2014 to January 2015 were enrolled. Protozoa were observed in bronchoalveolar lavage fluid by light microscopy. A total of 15 pediatric cases (11 male and 4 female individuals, from 1 year 8 months to 12 years 1 month of age) with flagellated protozoa infection diagnosed by light microscopy were recruited. The course of the disease at the time of diagnosis was from 10 days to 11 months. Patients presented with a fever (N = 9), cough (N = 11), wheezing (N = 5) and chest pain (N = 5). Laboratory data showed elevated peripheral blood leucocytes (N = 6), eosinophilic granulocytes (N = 3), C-reactive protein (N = 5) and immunoglobulin E (N = 3). Bronchoscopy revealed a mucus plug (N = 3) and bronchiectasis (N = 1). Lung computed tomography results indicated ground-glass opacification (N = 2), atelectasis (N = 3), bronchiectasis (N = 1), bronchial wall thickening (N = 3) or nodular opacity (N = 6, including 1 case of pulmonary embolism). All children responded to metronidazole for a 2- to 5-week treatment period. Patients with BPFP often have a chronic or recurrent course and present with recurrent fever, cough, wheezing and chest pain. Chest imaging may reveal ground-glass opacification, atelectasis, bronchiectasis or nodular opacity (including pulmonary embolism). BPFP responds favorably to metronidazole treatment.

Molecular characterization of Cryptosporidium spp. in poultry from Brazil

USDA-ARS?s Scientific Manuscript database

Cryptosporidiosis is an important zoonotic disease caused by the protozoa Cryptosporidium. Infections in birds are mainly caused by three species C. meleagridis, C. baileyi, and C. galli. C. meleagridis is the third most common cause of cryptosporidiosis in immunocompromised and immunocompetent huma...

Locally extensive meningoencephalitis caused by Miamiensis avidus (syn. Philasterides dicentrarchi) in a zebra shark.

PubMed

Li, Wen-Ta; Lo, Chieh; Su, Chen-Yi; Kuo, Hsuan; Lin, Susanne Je-Han; Chang, Hui-Wei; Pang, Victor Fei; Jeng, Chian-Ren

2017-10-18

Scuticociliatosis, caused by ciliated protozoa in the subclass Scuticociliatia of the phylum Ciliophora, can cause fatal disease in teleost fish species. However, information on scuticociliatosis in elasmobranchs is still scarce. In this report, we describe a case of locally extensive meningoencephalitis caused by Miamiensis avidus (syn. Philasterides dicentrarchi) in a 2 yr old captive zebra shark Stegostoma fasciatum. Granulocytic meningoencephalitis was observed through histological assessment. Inflammation was confined to the ventral aspect of the brain with a large number of ciliated protozoa, transforming into non-suppurative meningitis in the lateral aspect, and gradually vanished in the dorsal aspect. No histopathological and polymerase chain reaction (PCR) evidence of systemic dissemination of M. avidus was found. PCR targeting the gene coding the small-subunit ribosomal RNA (SSUrRNA) of M. avidus was performed on the brain, liver, and gill tissues, and only brain tissue yielded a positive result. The DNA sequences from amplicons of the protozoal SSUrRNA gene were completely matched to that of M. avidus. The distribution of protozoa in the current case was mainly located in the brain and suggests the possibility of a direct neural invasive pathway of M. avidus through the nasal cavity/ampullary system and/or a unique tissue tropism of M. avidus specific to the brain in zebra sharks. Further investigations on the pathogenesis of M. avidus in elasmobranchs, especially zebra sharks, are needed.

Cryptosporidium and Giardia in Humans, Domestic Animals, and Village Water Sources in Rural India

PubMed Central

Daniels, Miles E.; Shrivastava, Arpit; Smith, Woutrina A.; Sahu, Priyadarshi; Odagiri, Mitsunori; Misra, Pravas R.; Panigrahi, Pinaki; Suar, Mrutyunjay; Clasen, Thomas; Jenkins, Marion W.

2015-01-01

Cryptosporidium parvum and Giardia lamblia are zoonotic enteric protozoa of significant health concern where sanitation, hygiene, and water supplies are inadequate. We examined 85 stool samples from diarrhea patients, 111 pooled fecal samples by species across seven domestic animal types, and water from tube wells (N = 207) and ponds (N = 94) across 60 villages in coastal Odisha, India, for Cryptosporidium oocysts and Giardia cysts to measure occurrence, concentration/shedding, and environmental loading rates. Oocysts/cysts were detected in 12% of diarrhea patients. Detection ranged from 0% to 35% for Cryptosporidium and 0% to 67% for Giardia across animal hosts. Animal loading estimates indicate the greatest contributors of environmental oocysts/cysts in the study region are cattle. Ponds were contaminated with both protozoa (oocysts: 37%, cysts: 74%), as were tube wells (oocysts: 10%, cysts: 14%). Future research should address the public health concern highlighted from these findings and investigate the role of domestic animals in diarrheal disease transmission in this and similar settings. PMID:26123963

Effects of graded levels of tannin-containing tropical tree leaves on in vitro rumen fermentation, total protozoa and methane production.

PubMed

Bhatta, R; Saravanan, M; Baruah, L; Prasad, C S

2015-03-01

This study was carried out to determine the effect of graded levels of tannin-containing tropical tree leaves, Autocarpus integrifolis, Azardirachta indica and Ficus bengalensis, on the in vitro rumen fermentation pattern, total protozoa and methane suppression in order to establish the optimum dose of these leaves for inclusion in the ruminant diets. The air-dried and ground samples of Au. integrifolis, Az. indica and Ficus bengalensis were subjected to in vitro incubation using 30 ml buffered rumen fluid at 0, 2.5, 5.0, 10.0, 15.0, 20.0, 25.0 and 30.0% (dry matter refers to moisture-free basis) of a total mixed ration (TMR: refers to mixture of roughage and concentrate containing cereals and oil cakes) devoid of tannin. The TMR for the experimental incubation was prepared by mixing 40 parts of ground Elusine coracana straw as roughage source with 60 parts of concentrate mixture. The leaves contained an average 130 g kg(-1) CP with 7·0 MJ of ME kg(-1) DM. The average neutral detergent fibre (NDF) content was <400 g kg(-1) DM. Highest total phenol (TP; g kg(-1) DM) was recorded in Az. indica (108) followed by F. bengalensis (103) and Au. integrifolis (76), and total tannin (TT) content also showed similar trend. However, condensed tannin (CT) was highest in F. bengalensis (260) followed by Au. integrifolis (186) and Az. indica (138). There was significant (P < 0.05) reduction in the NH3 concentration in the presence of all the leaves. Autocarpus integrifolis tannins did not cause inhibition of total volatile fatty acid (TVFA: refers to the concentration of volatile fatty acids, viz. acetic, butyric and propionic) concentration, whereas F. bengalensis and Az. indica tannins at higher level of incubation (>5.0%) reduced TVFA concentration. Protozoa (cells per mL) were similar at all levels of inclusion with Au. integrifolis, but reduced in case of F. bengalensis and Az. indica. As the level of tannin increased in the incubation medium, there was a linear reduction in methane concentration. Highest methane reduction (%) was recorded in incubations supplemented with Az. indica (61.5) followed by F. bengalensis (46.8) and Au. integrifolis (30.3). It was established from this study that tropical leaves of F. bengalensis, Au. integrifolis and Az. indica suppress methanogenesis. Ficus bengalensis, Au. integrifolis and Az. indica leaves are of interest in the enteric methane ameliorative strategies. Total mixed ration containing 10-15% ground F. bengalensis or Au. integrifolis or Az. indica leaves could be fed to ruminants to reduce enteric methanogenesis. However, in vivo trials need to be carried out to validate these in vitro results. © 2014 The Society for Applied Microbiology.

Importance of Nonenteric Protozoan Infections in Immunocompromised People

PubMed Central

Barratt, J. L. N.; Harkness, J.; Marriott, D.; Ellis, J. T.; Stark, D.

2010-01-01

Summary: There are many neglected nonenteric protozoa able to cause serious morbidity and mortality in humans, particularly in the developing world. Diseases caused by certain protozoa are often more severe in the presence of HIV. While information regarding neglected tropical diseases caused by trypanosomatids and Plasmodium is abundant, these protozoa are often not a first consideration in Western countries where they are not endemic. As such, diagnostics may not be available in these regions. Due to global travel and immigration, this has become an increasing problem. Inversely, in certain parts of the world (particularly sub-Saharan Africa), the HIV problem is so severe that diseases like microsporidiosis and toxoplasmosis are common. In Western countries, due to the availability of highly active antiretroviral therapy (HAART), these diseases are infrequently encountered. While free-living amoebae are rarely encountered in a clinical setting, when infections do occur, they are often fatal. Rapid diagnosis and treatment are essential to the survival of patients infected with these organisms. This paper reviews information on the diagnosis and treatment of nonenteric protozoal diseases in immunocompromised people, with a focus on patients infected with HIV. The nonenteric microsporidia, some trypanosomatids, Toxoplasma spp., Neospora spp., some free-living amoebae, Plasmodium spp., and Babesia spp. are discussed. PMID:20930074

Rumen protozoa and methanogenesis: not a simple cause-effect relationship.

PubMed

Morgavi, Diego P; Martin, Cécile; Jouany, Jean-Pierre; Ranilla, Maria José

2012-02-01

Understanding the interactions between hydrogen producers and consumers in the rumen ecosystem is important for ruminant production and methane mitigation. The present study explored the relationships between rumen protozoa, methanogens and fermentation characteristics. A total of six donor sheep harbouring (F, faunated) or not (D, defaunated) protozoa in their rumens (D animals were kept without protozoa for a period of a few months (D - ) or for more than 2 years (D+)) were used in in vitro and in vivo experiments. In vitro the absence of protozoa decreased NH3 and butyrate production and had no effect on methane. In contrast, the liquid-associated bacterial and methanogens fraction of D+ inocula produced more methane than D -  and F inoculum (P < 0·05). In vivo fermentation parameters of donor animals showed the same trend on NH3 and butyrate and showed that D+ animals were high methane emitters, while D -  were the lowest ( - 35 %). The concentration of dissolved dihydrogen measured after feeding followed the opposite trend. Methane emissions did not correlate with the relative abundance of methanogens in the rumen measured by quantitative PCR, but there was a trend for higher methanogens concentration in the solid-associated population of D+ animals compared with D -  animals. In contrast, PCR-denaturing gradient gel electrophoresis profiles of methanogens' methyl coenzyme-M reductase A gene showed a clear clustering in liquid-associated fractions for all three groups of donors but fewer differences in solid-associated fractions. These results show that the absence of protozoa may affect differently the methanogen community and methane emissions in wethers.

Predation of nitritation-anammox biofilms used for nitrogen removal from wastewater.

PubMed

Suarez, Carolina; Persson, Frank; Hermansson, Malte

2015-11-01

Predation is assumed to be a major cause of bacterial mortality in wastewater treatment plants (WWTP). Grazing on the slowly growing autotrophic ammonia oxidizing bacteria (AOB) and anaerobic ammonium oxidizing bacteria (AMX) may result in loss of biomass, which could compromise nitrogen removal by the nitritation-anammox process. However, predation, particularly of anaerobic AMX, is unknown. We investigated the presence of protozoa, AOB and AMX and the possible predation in nitritation-anammox biofilms from several WWTPs. By fluorescence in situ hybridization (FISH) and confocal laser scanning microscopy (CLSM), predator and prey were localized in intact biofilm cryosections. Different broad morphological types of protozoa were found at different biofilm depths. Large variations in abundance of protozoa were seen. One reactor showed a predation event of amoeba-like protozoa, forming grazing fronts reaching deep biofilm regions that were dominated by the anaerobic AMX. Both AOB and AMX were grazed by the amoeba, as revealed by FISH-CLSM. Hence, even AMX, living in the deeper layers of stratified biofilms, are subjected to predation. Interestingly, different colocalization was observed between the amoeba-like protozoa and two different Ca. Brocadia AMX sublineages, indicating different grazing patterns. The findings indicate that predation pressure can be an important factor regulating the abundance of AOB and AMX, with implications for nitrogen removal from wastewater. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Microbiota and metabolic diseases.

PubMed

Pascale, Alessia; Marchesi, Nicoletta; Marelli, Cristina; Coppola, Adriana; Luzi, Livio; Govoni, Stefano; Giustina, Andrea; Gazzaruso, Carmine

2018-05-02

The microbiota is a complex ecosystem of microorganisms consisting of bacteria, viruses, protozoa, and fungi, living in different districts of the human body, such as the gastro-enteric tube, skin, mouth, respiratory system, and the vagina. Over 70% of the microbiota lives in the gastrointestinal tract in a mutually beneficial relationship with its host. The microbiota plays a major role in many metabolic functions, including modulation of glucose and lipid homeostasis, regulation of satiety, production of energy and vitamins. It exerts a role in the regulation of several biochemical and physiological mechanisms through the production of metabolites and substances. In addition, the microbiota has important anti-carcinogenetic and anti-inflammatory actions. There is growing evidence that any modification in the microbiota composition can lead to several diseases, including metabolic diseases, such as obesity and diabetes, and cardiovascular diseases. This is because alterations in the microbiota composition can cause insulin resistance, inflammation, vascular, and metabolic disorders. The causes of the microbiota alterations and the mechanisms by which microbiota modifications can act on the development of metabolic and cardiovascular diseases have been reported. Current and future preventive and therapeutic strategies to prevent these diseases by an adequate modulation of the microbiota have been also discussed.

Submission of nucleotide sequence eimeria acervulina profilin to genbank database

USDA-ARS?s Scientific Manuscript database

Poultry coccidiosis, caused by intestinal protozoa Eimeria, is a severe problem for the poultry industry, leading to a substantial economic burden of over three billion dollars worldwide. Conventional vaccines including live vaccines and attenuated vaccines could cause mild to severe reactions Numer...

Cryptosporidium and Giardia in Humans, Domestic Animals, and Village Water Sources in Rural India.

PubMed

Daniels, Miles E; Shrivastava, Arpit; Smith, Woutrina A; Sahu, Priyadarshi; Odagiri, Mitsunori; Misra, Pravas R; Panigrahi, Pinaki; Suar, Mrutyunjay; Clasen, Thomas; Jenkins, Marion W

2015-09-01

Cryptosporidium parvum and Giardia lamblia are zoonotic enteric protozoa of significant health concern where sanitation, hygiene, and water supplies are inadequate. We examined 85 stool samples from diarrhea patients, 111 pooled fecal samples by species across seven domestic animal types, and water from tube wells (N = 207) and ponds (N = 94) across 60 villages in coastal Odisha, India, for Cryptosporidium oocysts and Giardia cysts to measure occurrence, concentration/shedding, and environmental loading rates. Oocysts/cysts were detected in 12% of diarrhea patients. Detection ranged from 0% to 35% for Cryptosporidium and 0% to 67% for Giardia across animal hosts. Animal loading estimates indicate the greatest contributors of environmental oocysts/cysts in the study region are cattle. Ponds were contaminated with both protozoa (oocysts: 37%, cysts: 74%), as were tube wells (oocysts: 10%, cysts: 14%). Future research should address the public health concern highlighted from these findings and investigate the role of domestic animals in diarrheal disease transmission in this and similar settings. © The American Society of Tropical Medicine and Hygiene.

40 CFR 503.31 - Special definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... area (e.g., a strip mine located in a rural area). (f) Pathogenic organisms are disease-causing organisms. These include, but are not limited to, certain bacteria, protozoa, viruses, and viable helminth...

Expression of digestive enzymes and nutrient transporters in Eimeria-challenged broilers

USDA-ARS?s Scientific Manuscript database

Avian coccidiosis is a disease caused by the intestinal protozoa Eimeria. The site of invasion and lesions in the intestine is species-specific, for example E. acervulina affects the duodenum, E. maxima the jejunum, and E. tenella the ceca. Lesions in the intestinal mucosa cause reduced feed effic...

The role of protozoa-driven selection in shaping human genetic variability.

PubMed

Pozzoli, Uberto; Fumagalli, Matteo; Cagliani, Rachele; Comi, Giacomo P; Bresolin, Nereo; Clerici, Mario; Sironi, Manuela

2010-03-01

Protozoa exert a strong selective pressure in humans. The selection signatures left by these pathogens can be exploited to identify genetic modulators of infection susceptibility. We show that protozoa diversity in different geographic locations is a good measure of protozoa-driven selective pressure; protozoa diversity captured selection signatures at known malaria resistance loci and identified several selected single nucleotide polymorphisms in immune and hemolytic anemia genes. A genome-wide search enabled us to identify 5180 variants mapping to 1145 genes that are subjected to protozoa-driven selective pressure. We provide a genome-wide estimate of protozoa-driven selective pressure and identify candidate susceptibility genes for protozoa-borne diseases. Copyright 2010 Elsevier Ltd. All rights reserved.

Prevalence of sexually transmitted infections and enteric protozoa among homosexual men in western Sicily (south Italy).

PubMed

Di Benedetto, M A; Di Piazza, F; Amodio, E; Taormina, S; Romano, N; Firenze, A

2012-12-01

In recent years an increase in the number of sexually transmitted infections (STIs) in men who have sex with men (MSM) has been reported in different industrialised countries. Because few epidemiological data on the STls/MSM population in Sicily are available, a survey was conducted to assess the prevalence of STls/enteric protozoa and risky sexual behaviours among MSM in western Sicily. In 2010, 74 MSM with median age of 30 years old, were recruited via networks. All participants to the study were interviewed by anonymous self-administered questionnaire in order to collect social/demographic information, clinic data and STI-related risky sexual behaviours. After completing the questionnaire, blood samples were collected to determine HIV, HCV, HHV8 and Treponema pallidum antibodies; presence of Giardia duodenalis and Cryptosporidium parvum was also investigated in faecal samples by immunofluorescence assay. HIV, HHV8, T. pallidum and Giardia prevalence were 8.1%, 16.2%, 21.6% and 16.4% respectively; all patients were negative for HCV and Cryptosporidium infections. The median values of sexual anal intercourse and oral sex per week were 2 and 1, respectively. 7% of participants always had unprotected anal sex, 50.7% sometimes used condom during sexual anal intercourse and 42.3% always had protected anal sex. All MSM-HIV+ and 7 (43.7%) syphilis seropositives were unaware of their own infection. MSM in western Sicily are a high risk group for important STIs. It seems necessary that continuous interventions for preventing HIV/AIDS and other STls and for improving the level of knowledge of symptoms are needed.

Comparison of microscopic and immunoassay examination in the diagnosis of intestinal protozoa of humans in Mansoura, Egypt.

PubMed

Elswaifi, Shaadi F; Palmieri, James R; El-Tantawy, Nora; El-Hussiny, Mona; Besheer, Tarek; Abohashem, Ekbal

2016-09-01

Protozoal diseases are prevalent globally and especially in developing countries that have relatively lower socioeconomic populations such as Egypt. Direct microscopic examination (DME) is used for the detection and identification of protozoa but lacks sufficient reliability, and thus may be detrimental in obtaining accurate diagnostic or epidemiological data. In this study, we determine the prevalence of infections by Giardia intestinalis, Cryptosporidium sp., and Entamoeba histolytica in humans in Egypt. Furthermore, we determine the reliability of DME in determining infections caused by these protozoa and compare the results to enzyme linked Immunosorbent assays (ELISA). Our results indicate that the prevalence of giardiasis, cryptosporidiosis, and entamoebiasis is 38, 22, and 16 %, respectively. The sensitivity and specificity of DME for detection of G. intestinalis is 45 and 99 %, for Cryptosporidium 66 and 99 %, and for Entamoeba 45 and 100 %, respectively. Our findings demonstrate that ELISA is more reliable for diagnostic and epidemiologic study purposes.

Legionella pathogenicity: genome structure, regulatory networks and the host cell response.

PubMed

Steinert, Michael; Heuner, Klaus; Buchrieser, Carmen; Albert-Weissenberger, Christiane; Glöckner, Gernot

2007-11-01

Legionella spp. the causative agent of Legionnaires' disease is naturally found in fresh water where the bacteria parasitize intracellularly within protozoa. Upon aerosol formation via man-made water systems, Legionella can enter the human lung and cause a severe form of pneumonia. Here we review results from systematic comparative genome analysis of Legionella species with different pathogenic potentials. The complete genomes reveal that horizontal gene transfer has played an important role during the evolution of Legionella and indicate the importance of secretion machineries for the intracellular lifestyle of this pathogen. Moreover, we highlight recent findings on the in vivo transcriptional program of L. pneumophila and the regulatory networks involved in the biphasic life cycle. In order to understand how Legionella effectively subvert host cell functions for its own benefit the transcriptional host cell response upon infection of the model amoeba Dictyostelium discoideum was studied. The use of this model organism made it possible to develop a roadmap of host cell factors which significantly contribute to the uptake of L. pneumophila and the establishment of an ER-associated replicative vacuole.

Expression of digestive enzymes and nutrient transporters in the small intestine of Eimeria acervulina-infected chickens

USDA-ARS?s Scientific Manuscript database

Coccidiosis is a major disease of poultry caused by the intestinal protozoa Eimeria. Eimeria acervulina mainly infects the duodenum, causing lesions in epithelial tissue. The objective of this study was to investigate the effect of E. acervulina infection on the expression of 18 nutrient transport...

Relative diversity and community structure analysis of rumen protozoa according to T-RFLP and microscopic methods.

PubMed

Tymensen, Lisa; Barkley, Cindy; McAllister, Tim A

2012-01-01

Protozoa are common inhabitants of the rumen where they play roles in host nutrition and methanogenesis. Knowledge of how changes in the composition of protozoa communities affect these processes is limited in part due to a lack of efficient methods for protozoa community analysis. In this study, a terminal-restriction fragment length polymorphism (T-RFLP) assay targeting the 18S rRNA gene was developed for comparative analysis of rumen protozoa communities. Comparison of diversity and structure of protozoa communities from hay-fed versus silage/grain-fed cattle via T-RFLP analysis yielded similar overall results to microscopy analysis. According to both methods, Entodinium spp. were more abundant in the silage/grain-fed cattle and protozoa diversity (as calculated using the Shannon index) was higher for the hay-fed cattle due to greater species evenness. Type B protozoa were more prevalent in the hay-fed cattle, whereas Type A protozoa were more prevalent in the silage/grain-fed cattle. Analysis of similarity (ANOSIM) indicated that the protozoa communities from hay-fed and silage/grain-fed cattle were different, and multivariate analysis indicated that pen mates (i.e., cattle fed the same diet and housed together) tended to have similar protozoa communities types. In summary, we present a T-RFLP method for analyzing rumen protozoa communities which complements traditional microscopy approaches but has the advantage of being amenable to high-throughput. Copyright © 2011. Published by Elsevier B.V.

The Role of Ciliate Protozoa in the Rumen

PubMed Central

Newbold, Charles J.; de la Fuente, Gabriel; Belanche, Alejandro; Ramos-Morales, Eva; McEwan, Neil R.

2015-01-01

First described in 1843, Rumen protozoa with their striking appearance were assumed to be important for the welfare of their host. However, despite contributing up to 50% of the bio-mass in the rumen, the role of protozoa in rumen microbial ecosystem remains unclear. Phylogenetic analysis of 18S rDNA libraries generated from the rumen of cattle, sheep, and goats has revealed an unexpected diversity of ciliated protozoa although variation in gene copy number between species makes it difficult to obtain absolute quantification. Despite repeated attempts it has proven impossible to maintain rumen protozoa in axenic culture. Thus it has been difficult to establish conclusively a role of ciliate protozoa in rumen fiber degradation. The development of techniques to clone and express ciliate genes in λ phage, together with bioinformatic indices to confirm the ciliate origin of the genes has allowed the isolation and characterization of fibrolytic genes from rumen protozoa. Elimination of the ciliate protozoa increases microbial protein supply by up to 30% and reduces methane production by up to 11%. Our recent findings suggest that holotrich protozoa play a disproportionate role in supporting methanogenesis whilst the small Entodinium are responsible for much of the bacterial protein turnover. As yet no method to control protozoa in the rumen that is safe and practically applicable has been developed, however a range of plant extract capable of controlling if not completely eliminating rumen protozoa have been described. PMID:26635774

The Role of Ciliate Protozoa in the Rumen.

PubMed

Newbold, Charles J; de la Fuente, Gabriel; Belanche, Alejandro; Ramos-Morales, Eva; McEwan, Neil R

2015-01-01

First described in 1843, Rumen protozoa with their striking appearance were assumed to be important for the welfare of their host. However, despite contributing up to 50% of the bio-mass in the rumen, the role of protozoa in rumen microbial ecosystem remains unclear. Phylogenetic analysis of 18S rDNA libraries generated from the rumen of cattle, sheep, and goats has revealed an unexpected diversity of ciliated protozoa although variation in gene copy number between species makes it difficult to obtain absolute quantification. Despite repeated attempts it has proven impossible to maintain rumen protozoa in axenic culture. Thus it has been difficult to establish conclusively a role of ciliate protozoa in rumen fiber degradation. The development of techniques to clone and express ciliate genes in λ phage, together with bioinformatic indices to confirm the ciliate origin of the genes has allowed the isolation and characterization of fibrolytic genes from rumen protozoa. Elimination of the ciliate protozoa increases microbial protein supply by up to 30% and reduces methane production by up to 11%. Our recent findings suggest that holotrich protozoa play a disproportionate role in supporting methanogenesis whilst the small Entodinium are responsible for much of the bacterial protein turnover. As yet no method to control protozoa in the rumen that is safe and practically applicable has been developed, however a range of plant extract capable of controlling if not completely eliminating rumen protozoa have been described.

Infectious diarrhoea in antiretroviral therapy-naïve HIV/AIDS patients in Kenya

PubMed Central

Wanyiri, Jane W.; Kanyi, Henry; Maina, Samuel; Wang, David E.; Ngugi, Paul; O'Connor, Roberta; Kamau, Timothy; Waithera, Tabitha; Kimani, Gachuhi; Wamae, Claire N.; Mwamburi, Mkaya; Ward, Honorine D.

2013-01-01

Background Diarrhoea is a significant cause of morbidity and mortality in immunocompromised patients. The objectives of this study were to investigate the aetiological agents, risk factors and clinical features associated with diarrhoea in HIV/AIDS patients in Kenya. Methods Sociodemographic, epidemiological and clinical data were obtained for 164 HIV/AIDS patients (70 with and 94 without diarrhoea) recruited from Kenyatta National Hospital, Kenya. Stool samples were examined for enteric pathogens by microscopy and bacteriology. Results Intestinal protozoa and fungi were identified in 70% of patients, more frequently in those with diarrhoea (p<0.001). Helminths were detected in 25.6% of patients overall, and bacterial pathogens were identified in 51% of patients with diarrhoea. Polyparasitism was more common in patients with diarrhoea than those without (p<0.0001). Higher CD4+ T-cell count (OR = 0.995, 95% CI 0.992–0.998) and water treatment (OR = 0.231, 95% CI 0.126–0.830) were associated with a lower risk of diarrhoea, while close contact with cows (OR = 3.200, 95% CI 1.26–8.13) or pigs (OR = 11.176, 95% CI 3.76–43.56) were associated with a higher risk of diarrhoea. Conclusions Multiple enteric pathogens that are causative agents of diarrhoea were isolated from stools of antiretroviral therapy-naïve HIV/AIDS patients, indicating a need for surveillance, treatment and promotion of hygienic practices. PMID:24026463

Protozoa interaction with aquatic invertebrate: interest for watercourses biomonitoring.

PubMed

Palos Ladeiro, M; Bigot, A; Aubert, D; Hohweyer, J; Favennec, L; Villena, I; Geffard, A

2013-02-01

Toxoplasma gondii, Cryptosporidium parvum, and Giardia duodenalis are human waterborne protozoa. These worldwide parasites had been detected in various watercourses as recreational, surface, drinking, river, and seawater. As of today, water protozoa detection was based on large water filtration and on sample concentration. Another tool like aquatic invertebrate parasitism could be used for sanitary and environmental biomonitoring. In fact, organisms like filter feeders could already filtrate and concentrate protozoa directly in their tissues in proportion to ambient concentration. So molluscan shellfish can be used as a bioindicator of protozoa contamination level in a site since they were sedentary. Nevertheless, only a few researches had focused on nonspecific parasitism like protozoa infection on aquatic invertebrates. Objectives of this review are twofold: Firstly, an overview of protozoa in worldwide water was presented. Secondly, current knowledge of protozoa parasitism on aquatic invertebrates was detailed and the lack of data of their biological impact was pointed out.

Intestinal protozoa infections among patients with ulcerative colitis: prevalence and impact on clinical disease course.

PubMed

Yamamoto-Furusho, Jesús K; Torijano-Carrera, Emma

2010-01-01

Epidemiological and microbiologic studies suggest that enteropathogenic microorganisms play a substantial role in the clinical initiation and relapses of inflammatory bowel disease. To explore the prevalence of intestinal protozoa in patients with ulcerative colitis (UC) and its impact on clinical disease course. A total of 215 patients with definitive diagnosis of UC were studied. Fresh feces samples taken from all UC patients were examined immediately using trichrome-staining methods. A total of 103 female and 112 male UC patients were analyzed. The mean age at diagnosis was 30.5 +/- 10.8 years. The prevalence of overall parasitic infections was 24% and distributed as follows: Blastocystis hominis in 22 patients (10%), Endolimax nana in 19 cases (9%), and Entamoebahistolytica in 11 cases (5%). A significantly increased frequency of protozoa infection was found in those patients with persistent activity and intermittent activity as compared to active than inactive group (p = 1 x 10(-7), OR 13.05, 95% CI 4.28-42.56, and p = 0.003, OR 1.42-14.47, respectively). Interestingly, this association remained significant when we compared the persistent activity group versus intermittent activity group (p = 0.003, OR 2.97, 95% CI 1.35-6.59). Subgroup analysis showed no association between protozoa infection (E. histolytica, B. hominis, and E. nana) and other clinical variables such as gender, extent of disease, extraintestinal complications, medical treatment and grade of disease activity. The prevalence of intestinal protozoa infections in Mexican UC patients was 24% and these microorganisms could be a contributing cause of persistent activity despite medical treatment in our population. 2010 S. Karger AG, Basel.

Molecular identification of protozoa causing AIDS-associated cholangiopathy in Buenos Aires, Argentina.

PubMed

Nétor Velásquez, Jorge; Marta, Edgardo; Alicia di Risio, Cecilia; Etchart, Cristina; Gancedo, Elisa; Victor Chertcoff, Agustín; Bruno Malandrini, Jorge; Germán Astudillo, Osvaldo; Carnevale, Silvana

2012-12-01

Several species of microsporidia and coccidia are protozoa parasites responsible for cholan-giopathy disease in patients infected with human immunodeficiency virus (HIV). The goals of this work were to identift opportunistic protozoa by molecular methods and describe the clinical manifestations at the gastrointestinal tract and the biliary system in patients with AIDS-associated cholangiopathy from Buenos Aires, Argentina. This study included 11 adult HIV-infected individuals with diagnosis ofAIDS- associated cholangiopathy. An upper gastrointestinal endoscopy with biopsy specimen collection and a stool analysis for parasites were performed on each patient. The ultrasound analysis revealed bile ducts compromise. An endoscopic retrograde cholangiopancreatography and a magnetic resonance cholangiography were carried out. The identification to the species level was performed on biopsy specimens by molecular methods. Microorganisms were identified in 10 cases. The diagnosis in patients with sclerosing cholangitis was cryptosporidiosis in 3 cases, cystoisosporosis in 1 and microsporidiosis in 1. In patients with sclerosing cholangitis and papillary stenosis the diagnosis was microsporidiosis in 2 cases, cryptosporidiosis in 2 and cryptosporidiosis associated with microsporidiosis in 1. In 3 cases with cryptosporidiosis the species was Cryptosporidium hominis, 1 of them was associated with Enterocytozoon bieneusi, and the other 2 were coinfected with Cryptosporidium parvum. In the 4 cases with microsporidiosis the species was Enterocytozoon bieneusi. These results suggest that molecular methods may be useful tools to identify emerging protozoa in patients with AIDS-associated cholangiopathy.

Contribution of Ruminal Fungi, Archaea, Protozoa, and Bacteria to the Methane Suppression Caused by Oilseed Supplemented Diets

PubMed Central

Wang, Shaopu; Giller, Katrin; Kreuzer, Michael; Ulbrich, Susanne E.; Braun, Ueli; Schwarm, Angela

2017-01-01

Dietary lipids can suppress methane emission from ruminants, but effects are variable. Especially the role of bacteria, archaea, fungi and protozoa in mediating the lipid effects is unclear. In the present in vitro study, archaea, fungi and protozoa were selectively inhibited by specific agents. This was fully or almost fully successful for fungi and protozoa as well as archaeal activity as determined by the methyl-coenzyme M reductase alpha subunit gene. Five different microbial treatments were generated: rumen fluid being intact (I), without archaea (–A), without fungi (–F), without protozoa (–P) and with bacteria only (–AFP). A forage-concentrate diet given alone or supplemented with crushed full-fat oilseeds of either safflower (Carthamus tinctorius) or poppy (Papaver somniferum) or camelina (Camelina sativa) at 70 g oil kg−1 diet dry matter was incubated. This added up to 20 treatments with six incubation runs per treatment. All oilseeds suppressed methane emission compared to the non-supplemented control. Compared to the non-supplemented control, –F decreased organic matter (OM) degradation, and short-chain fatty acid concentration was greater with camelina and safflower seeds. Methane suppression per OM digested in –F was greater with camelina seeds (−12 vs.−7% with I, P = 0.06), but smaller with poppy seeds (−4 vs. −8% with I, P = 0.03), and not affected with safflower seeds. With –P, camelina seeds decreased the acetate-to-propionate ratio and enhanced the methane suppression per gram dry matter (18 vs. 10% with I, P = 0.08). Hydrogen recovery was improved with –P in any oilseeds compared to non-supplemented control. No methane emission was detected with the –A and –AFP treatments. In conclusion, concerning methanogenesis, camelina seeds seem to exert effects only on archaea and bacteria. By contrast, with safflower and poppy seeds methane was obviously reduced mainly through the interaction with protozoa or archaea associated with protozoa. This demonstrated that the microbial groups differ in their contribution to the methane suppressing effect dependent on the source of lipid. These findings help to understand how lipid supplementation and microbial groups interact, and thus may assist in making this methane mitigation tool more efficient, but await confirmation in vivo. PMID:29033916

Contribution of Ruminal Fungi, Archaea, Protozoa, and Bacteria to the Methane Suppression Caused by Oilseed Supplemented Diets.

PubMed

Wang, Shaopu; Giller, Katrin; Kreuzer, Michael; Ulbrich, Susanne E; Braun, Ueli; Schwarm, Angela

2017-01-01

Dietary lipids can suppress methane emission from ruminants, but effects are variable. Especially the role of bacteria, archaea, fungi and protozoa in mediating the lipid effects is unclear. In the present in vitro study, archaea, fungi and protozoa were selectively inhibited by specific agents. This was fully or almost fully successful for fungi and protozoa as well as archaeal activity as determined by the methyl-coenzyme M reductase alpha subunit gene. Five different microbial treatments were generated: rumen fluid being intact (I), without archaea (-A), without fungi (-F), without protozoa (-P) and with bacteria only (-AFP). A forage-concentrate diet given alone or supplemented with crushed full-fat oilseeds of either safflower ( Carthamus tinctorius ) or poppy ( Papaver somniferum ) or camelina ( Camelina sativa ) at 70 g oil kg -1 diet dry matter was incubated. This added up to 20 treatments with six incubation runs per treatment. All oilseeds suppressed methane emission compared to the non-supplemented control. Compared to the non-supplemented control, -F decreased organic matter (OM) degradation, and short-chain fatty acid concentration was greater with camelina and safflower seeds. Methane suppression per OM digested in -F was greater with camelina seeds (-12 vs.-7% with I, P = 0.06), but smaller with poppy seeds (-4 vs. -8% with I, P = 0.03), and not affected with safflower seeds. With -P, camelina seeds decreased the acetate-to-propionate ratio and enhanced the methane suppression per gram dry matter (18 vs. 10% with I, P = 0.08). Hydrogen recovery was improved with -P in any oilseeds compared to non-supplemented control. No methane emission was detected with the -A and -AFP treatments. In conclusion, concerning methanogenesis, camelina seeds seem to exert effects only on archaea and bacteria. By contrast, with safflower and poppy seeds methane was obviously reduced mainly through the interaction with protozoa or archaea associated with protozoa. This demonstrated that the microbial groups differ in their contribution to the methane suppressing effect dependent on the source of lipid. These findings help to understand how lipid supplementation and microbial groups interact, and thus may assist in making this methane mitigation tool more efficient, but await confirmation in vivo .

Association between protozoa in sputum and asthma: a case-control study.

PubMed

van Woerden, Hugo C; Ratier-Cruz, Adriana; Aleshinloye, Olabode B; Martinez-Giron, Rafael; Gregory, Clive; Matthews, Ian P

2011-06-01

Atypical infectious agents have been proposed as potential contributors to asthma. A novel set of morphological and staining criteria permit the identification of flagellated protozoa in sputum. This case-control study was designed to use this novel method and to assess: (1) are protozoa more common in asthmatics than in non-asthmatics; (2) is the presence of protozoa associated with the use of steroid inhalers; and (3) is the presence of protozoa associated with living in damp housing? Induced sputum samples were collected from asthma patients and local non-atopic, non-smoking controls. Questionnaires assessed asthma severity and housing conditions. Sputum was examined for flagellated protozoa using a previously described staining technique. 96 participants were recruited for this study; 54 asthma patients and 42 controls, age range 21-62 years, 70% female participants. Limiting results to those who were clearly positive or negative for flagellated protozoa, 66.7% (20/30) of asthmatics and 30.8% (4/13) of controls had protozoa (p = 0.046). Among the asthma patients, prevalence of protozoa was not significantly different between those who had (10/18), and those who had not (10/12), used steroid inhaler in the preceding two weeks (p = 0.11). Similarly, the prevalence of protozoa was not significantly different between those who did (6/11) and those who did not (18/32), live in damp homes (p = 0.92). This case-control study demonstrates an association between flagellated protozoa in sputum and asthma. It is now necessary to confirm and characterise the protozoa using genetic techniques based on 18S ribosomal RNA. Once tis is established it would be worthwhile to determine if asthma symptoms improve when treated by anti-protozoal agents. Copyright © 2010 Elsevier Ltd. All rights reserved.

[Predation of micro-protozoa on bacteria in Taihu Lake].

PubMed

Chen, Mo; Gao, Guang; Zhu, Li-Ping; Feng, Sheng

2007-10-01

With dilution method, this paper studied the predation of different size micro-protozoa on bacteria in Taihu Lake, and approached the effects of the predation on bacterial growth and of the water temperature on the predation. The results showed that in the water body of Taihu Lake, the predation rate of micro-protozoa with its size less than 32 microm was 5.07 d(-1), and the nano-size (less than 16 microm) protozoa contributed about 90.7%. The predation of nano-protozoa reduced the abundance of bacteria significantly. With the increase of water temperature, the predation rate of nano-protozoa and the growth rate of bacteria increased obviously.

Comparisons of Salmonella conjugation and virulence gene hyperexpression mediated by rumen protozoa from domestic and exotic ruminants.

PubMed

Brewer, Matt T; Xiong, Nalee; Dier, Jeffery D; Anderson, Kristi L; Rasmussen, Mark A; Franklin, Sharon K; Carlson, Steve A

2011-08-05

Recent studies have identified a phenomenon in which ciliated protozoa engulf Salmonella and the intra-protozoal environment hyperactivates virulence gene expression and provides a venue for conjugal transfer of antibiotic resistance plasmids. The former observation is relegated to Salmonella bearing the SGI1 multiresistance integron while the latter phenomenon appears to be a more generalized event for recipient Salmonella. Our previous studies have assessed virulence gene hyperexpression only with protozoa from the bovine rumen while conjugal transfer has been demonstrated in rumen protozoa from cattle and goats. The present study examined virulence gene hyperexpression for Salmonella exposed to rumen protozoa obtained from cattle, sheep, goats, or two African ruminants (giraffe and bongo). Conjugal transfer was also assessed in these protozoa using Salmonella as the recipient. Virulence gene hyperexpression was only observed following exposure to the rumen protozoa from cattle and sheep while elevated virulence was also observed in these animals. Conjugal transfer events were, however, observed in all protozoa evaluated. It therefore appears that the protozoa-based hypervirulence is not universal to all ruminants while conjugal transfer is more ubiquitous. Copyright © 2011 Elsevier B.V. All rights reserved.

A comparative study of the TF-Test®, Kato-Katz, Hoffman-Pons-Janer, Willis and Baermann-Moraes coprologic methods for the detection of human parasitosis.

PubMed

Carvalho, Gabriela Lanna Xavier de; Moreira, Luciano Evangelista; Pena, João Luiz; Marinho, Carolina Coimbra; Bahia, Maria Terezinha; Machado-Coelho, George Luiz Lins

2012-02-01

This study compares the diagnostic accuracy of the TF-Test(®) (TFT) for human parasitosis with results obtained using the traditional Kato-Katz (KK), Hoffman-Pons-Janer (HPJ), Willis and Baermann-Moraes (BM) techniques. Overall, four stool samples were taken from each individual; three alternate-day TFT stool samples and another sample that was collected in a universal container. Stool samples were taken from 331 inhabitants of the community of Quilombola Santa Cruz. The gold standard (GS) for protozoa detection was defined as the combined results for TFT, HPJ and Willis coproscopic techniques; for helminth detection, GS was defined as the combined results for all five coproscopic techniques (TFT, KK, HPJ, Willis and BM). The positivity rate of each method was compared using the McNemar test. While the TFT exhibited similar positivity rates to the GS for Entamoeba histolytica/dispar (82.4%) and Giardia duodenalis (90%), HPJ and Willis techniques exhibited significantly lower positivity rates for these protozoa. All tests exhibited significantly lower positivity rates compared with GS for the diagnosis of helminths. The KK technique had the highest positivity rate for diagnosing Schistosoma mansoni (74.6%), while the TFT had the highest positivity rates for Ascaris lumbricoides (58.1%) and hookworm (75%); HPJ technique had the highest positivity rate for Strongyloides stercoralis (50%). Although a combination of tests is the most accurate method for the diagnosis of enteral parasites, the TFT reliably estimates the prevalence of protozoa and selected helminths, such as A. lumbricoides and hookworm. Further studies are needed to evaluate the detection accuracy of the TFT in samples with varying numbers of parasites.

QUANTITATIVE ASSESSMENT OF PATHOGENS IN DRINKING WATER

EPA Science Inventory

The project has been summarized in a series of peer-reviewed published papers as outlined in the Publication section of this report. Pathogens capable of causing waterborne diseases include bacteria, protozoa, and viruses. Fecal indicator bacteria are the primary microorganisms u...

Screening of agelasine D and analogs for inhibitory activity against pathogenic protozoa; identification of hits for visceral leishmaniasis and Chagas disease.

PubMed

Vik, Anders; Proszenyák, Agnes; Vermeersch, Marieke; Cos, Paul; Maes, Louis; Gundersen, Lise-Lotte

2009-01-08

There is an urgent need for novel and improved drugs against several tropical diseases caused by protozoa. The marine sponge (Agelas sp.) metabolite agelasine D, as well as other agelasine analogs and related structures were screened for inhibitory activity against Plasmodium falciparum, Leishmania infantum, Trypanosoma brucei and T. cruzi, as well as for toxicity against MRC-5 fibroblast cells. Many compounds displayed high general toxicity towards both the protozoa and MRC-5 cells. However, two compounds exhibited more selective inhibitory activity against L. infantum (IC(50) <0.5 microg/mL) while two others displayed IC(50) <1 microg/mL against T. cruzi in combination with relatively low toxicity against MRC-5 cells. According to criteria set up by the WHO Special Programme for Research & Training in Tropical Diseases (TDR), these compounds could be classified as hits for leishmaniasis and for Chagas disease, respectively. Identification of the hits as well as other SAR data from this initial screening will be valuable for design of more potent and selective potential drugs against these neglected tropical diseases.

Case-control study of diarrheal disease etiology in individuals over 5 years in southwest China.

PubMed

Zhang, Shun-Xian; Yang, Chun-Li; Gu, Wen-Peng; Ai, Lin; Serrano, Emmanuel; Yang, Pin; Zhou, Xia; Li, Shi-Zhu; Lv, Shan; Dang, Zhi-Sheng; Chen, Jun-Hu; Hu, Wei; Tian, Li-Guang; Chen, Jia-Xu; Zhou, Xiao-Nong

2016-01-01

Acute diarrhea is one of the major public health problems worldwide. Most of studies on acute diarrhea have been made on infants aged below 5 years and few efforts have been made to identify the etiological agents of acute diarrhea in people over five, especially in China. 271 diarrhea cases and 149 healthy controls over 5 years were recruited from four participating hospitals between June 2014 and July 2015. Each stool specimen was collected to detect a series of enteric pathogens, involving five viruses ( Rotavirus group A, RVA; Norovirus , NoV; Sapovirus , SaV; Astrovirus , As; and Adenovirus , Ad), seven bacteria (diarrheagenic Escherichia coli , DEC; non-typhoidal Salmonella , NTS; Shigella spp.; Vibrio cholera; Vibrio parahaemolyticus ; Aeromonas spp.; and Plesiomonas spp.) and three protozoa ( Cryptosporidium spp., Giardia lamblia, G. lamblia , and Blastocystis hominis, B. hominis ). Standard microbiological and molecular methods were applied to detect these pathogens. Data was analyzed using Chi square, Fisher-exact tests and logistic regressions. The prevalence of at least one enteric pathogen was detected in 29.2% (79/271) acute diarrhea cases and in 12.1% (18/149) in healthy controls ( p  < 0.0001). Enteric viral infections (14.4%) were the most common in patients suffering from acute diarrhea, followed by bacteria (13.7%) and intestinal protozoa (4.8%). DEC (12.5%) was the most common causative agent in diarrhea cases, followed by NoV GII (10.0%), RVA (7.4%) and B. hominis (4.8%). The prevalence of co-infection was statistically higher ( p  = 0.0059) in the case group (7.7%) than in the healthy control (1.3%). RVA-NoV GII (3.0%) was the most common co-infection in symptomatic cases. DEC was the most predominant pathogen in diarrhea cases, but it was largely overlooked because the lack of laboratory capacities. Because of the high prevalence of co-infections, it is recommended the urgent development of alternative laboratory methods to assess polymicrobial infections. Such methodological improvements will result in a better prevention and treatment strategies to control diarrhea illness in China.

Factors affecting the rate of breakdown of bacterial protein in rumen fluid.

PubMed

Wallace, R J; McPherson, C A

1987-09-01

1. The cellular proteins of Butyrivibrio fibrisolvens, Lactobacillus casei, Megasphaera elsdenii, Selenomonas ruminantium and Streptococcus bovis were labelled by growth in the presence of L-[14C]leucine, and the breakdown of labelled protein was measured in incubations of these bacteria with rumen fluid to which unlabelled 5 mM-L-leucine was added. The rate of protein breakdown was estimated from the rate of release of radioactivity into acid-soluble material. 2. Protein breakdown occurred at different rates in different species. The mean rates for B. fibrisolvens, L. casei, M. elsdenii, Sel. ruminantium and Str. bovis were 28.6, 18.1, 17.7, 10.5 and 5.3%/h respectively in samples of strained rumen fluid (SRF) with different protozoal populations. Rates of 3%/h or less were found in SRF from ciliate-free sheep or in faunated SRF from which protozoa had been removed by centrifugation. Further removal of mixed rumen bacteria had little effect. Suspensions of washed protozoa degraded bacterial protein at rates which were of the same order as those found in SRF. 3. The rate of breakdown of bacterial protein in different samples of SRF tended to increase as the numbers of small entodiniomorphid protozoa increased. The numbers of larger entodiniomorphs and holotrichs had no obvious influence on this rate. 4. Autoclaved and u.v.-treated bacteria were generally no different from live bacteria in their susceptibility to breakdown in SRF from faunated sheep, indicating that endogenous protein turnover was not a significant cause of bacterial protein catabolism. 5. The rate of bacterial protein breakdown was unrelated to the proteolytic activity of SRF. 6. It was concluded that predation by small protozoa is by far the most important cause of bacterial protein turnover in the rumen, with autolysis, other lytic factors and endogenous proteolysis being of minor importance.

Coccidia and other Protozoa

USDA-ARS?s Scientific Manuscript database

Pigs are important to the economy of the US. Control of infectious diseases is necessary for the success of swine industry. In the present book chapter the authors review current information on protozoan infections of pigs. The coccidium Cystoisospora suis causes diarrhea in newborn pigs. Public hea...

Modeling the distribution of ciliate protozoa in the reticulo-rumen using linear programming.

PubMed

Hook, S E; Dijkstra, J; Wright, A-D G; McBride, B W; France, J

2012-01-01

The flow of ciliate protozoa from the reticulo-rumen is significantly less than expected given the total density of rumen protozoa present. To maintain their numbers in the reticulo-rumen, protozoa can be selectively retained through association with feed particles and the rumen wall. Few mathematical models have been designed to model rumen protozoa in both the free-living and attached phases, and the data used in the models were acquired using classical techniques. It has therefore become necessary to provide an updated model that more accurately represents these microorganisms and incorporates the recent literature on distribution, sequestration, and generation times. This paper represents a novel approach to synthesizing experimental data on rumen microorganisms in a quantitative and structured manner. The development of a linear programming model of rumen protozoa in an approximate steady state will be described and applied to data from healthy ruminants consuming commonly fed diets. In the model, protozoa associated with the liquid phase and protozoa attached to particulate matter or sequestered against the rumen wall are distinguished. Growth, passage, death, and transfer of protozoa between both pools are represented. The results from the model application using the contrasting diets of increased forage content versus increased starch content indicate that the majority of rumen protozoa, 63 to 90%, are found in the attached phase, either attached to feed particles or sequestered on the rumen wall. A slightly greater proportion of protozoa are found in the attached phase in animals fed a hay diet compared with a starch diet. This suggests that experimental protocols that only sample protozoa from the rumen fluid could be significantly underestimating the size of the protozoal population of the rumen. Further data are required on the distribution of ciliate protozoa in the rumen of healthy animals to improve model development, but the model described herein does indicate that the attached protozoal population is a significant component of the total rumen protozoal community. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Detection of Intestinal Protozoa in the Clinical Laboratory

PubMed Central

McHardy, Ian H.; Wu, Max; Shimizu-Cohen, Robyn; Couturier, Marc Roger

2014-01-01

Despite recent advances in diagnostic technology, microscopic examination of stool specimens remains central to the diagnosis of most pathogenic intestinal protozoa. Microscopy is, however, labor-intensive and requires a skilled technologist. New, highly sensitive diagnostic methods have been developed for protozoa endemic to developed countries, including Giardia lamblia (syn. G. intestinalis/G. duodenalis) and Cryptosporidium spp., using technologies that, if expanded, could effectively complement or even replace microscopic approaches. To date, the scope of such novel technologies is limited and may not include common protozoa such as Dientamoeba fragilis, Entamoeba histolytica, or Cyclospora cayetanensis. This minireview describes canonical approaches for the detection of pathogenic intestinal protozoa, while highlighting recent developments and FDA-approved tools for clinical diagnosis of common intestinal protozoa. PMID:24197877

Detection of intestinal protozoa in the clinical laboratory.

PubMed

McHardy, Ian H; Wu, Max; Shimizu-Cohen, Robyn; Couturier, Marc Roger; Humphries, Romney M

2014-03-01

Despite recent advances in diagnostic technology, microscopic examination of stool specimens remains central to the diagnosis of most pathogenic intestinal protozoa. Microscopy is, however, labor-intensive and requires a skilled technologist. New, highly sensitive diagnostic methods have been developed for protozoa endemic to developed countries, including Giardia lamblia (syn. G. intestinalis/G. duodenalis) and Cryptosporidium spp., using technologies that, if expanded, could effectively complement or even replace microscopic approaches. To date, the scope of such novel technologies is limited and may not include common protozoa such as Dientamoeba fragilis, Entamoeba histolytica, or Cyclospora cayetanensis. This minireview describes canonical approaches for the detection of pathogenic intestinal protozoa, while highlighting recent developments and FDA-approved tools for clinical diagnosis of common intestinal protozoa.

Amoebic meningoencephalitis in Samarinda East Kalimantan

NASA Astrophysics Data System (ADS)

Siagian, L. R. D.; Toruan, V. M. L.; Hutahaen, Y. O.; Gunawan, C.

2018-04-01

Meningoencephalitis is a disease of central nervous system caused by s microorganism such as bacteria, Rickettsiae, Spirochaeta, virus, fungus, protozoa and helminth. Free living amoeba protozoa has been reported as an etiology agent of menigoencephalitis. Amoebic meningoencephalitis is a very rare condition and often fatal because of late diagnosis. We reported a 24 years old woman, hospitalized at Abdul Wahab Syahranie’s Hospital, Samarinda East Kalimantan with decreased of consciousness and fever. The brain MRI showed focal lession suggested as a granuloma. ed Microorganisms like cyst and trophozoit with pseudopodia amoeboic form were identified from the cerebrospinal fluid. Based on these findings the patient was diagnosed with amoebic meningoencephalitis infection and got intravenous metronidazole. The patient died on the twenty third days of hospitalization..

Prevalence of protozoa species in drinking and environmental water sources in Sudan.

PubMed

Shanan, Salah; Abd, Hadi; Bayoumi, Magdi; Saeed, Amir; Sandström, Gunnar

2015-01-01

Protozoa are eukaryotic cells distributed worldwide in nature and are receiving increasing attention as reservoirs and potential vectors for the transmission of pathogenic bacteria. In the environment, on the other hand, many genera of the protozoa are human and animal pathogens. Only limited information is available on these organisms in developing countries and so far no information on their presence is available from Sudan. It is necessary to establish a molecular identification of species of the protozoa from drinking and environmental water. 600 water samples were collected from five states (Gadarif, Khartoum, Kordofan, Juba, and Wad Madani) in Sudan and analysed by polymerase chain reaction (PCR) and sequencing. 57 out of 600 water samples were PCR positive for protozoa. 38 out of the 57 positive samples were identified by sequencing to contain 66 protozoa species including 19 (28.8%) amoebae, 17 (25.7%) Apicomplexa, 25 (37.9%) ciliates, and 5 (7.6%) flagellates. This study utilized molecular methods identified species belonging to all phyla of protozoa and presented a fast and accurate molecular detection and identification of pathogenic as well as free-living protozoa in water uncovering hazards facing public health.

Prevalence of Intestinal Protozoa Infections and Associated Risk Factors among Schoolchildren in Sanandaj City, Iran.

PubMed

Bahmani, Pegah; Maleki, Afshin; Sadeghi, Shahram; Shahmoradi, Behzad; Ghahremani, Esmaeil

2017-01-01

Intestinal parasites are still a serious public health problem in the world, especially in developing countries. This study aimed to assess the prevalence of intestinal protozoa infections and associated risk factors among schoolchildren in Sanandaj City, Iran. This cross-sectional study involving 400 schoolchildren was carried out in 2015. Each student was selected using systematic random sampling method. Questionnaire and observation were used to identify possible risk factors. Fresh stool samples were observed using formal-ether concentration method. Five species of intestinal protozoa were identified with an overall prevalence of 42.3%. No cases of helminthes infection were detected. The predominant protozoa were Blastocys hominis (21.3%) and Entamoeba coli (4.5%). Overall, 143 (35.9%) had single infections and 26 (6.4%) were infected with more than one intestinal protozoa, in which 23 (5.9%) had double intestinal protozoa infections and 3 (0.5%) had triple infections. A significant relationship was observed between intestinal protozoa infection with economic status, water resources for drinking uses, and the methods of washing vegetables ( P <0.05). Education programs on students and their families should be implemented for the prevention and control of protozoa infections in the study area.

Subclinical Enteric Parasitic Infections and Growth Faltering in Infants in São Tomé, Africa: A Birth Cohort Study

PubMed Central

Garzón, Marisol; Seixas, Jorge; Papoila, Ana Luísa; Alves, Marta

2018-01-01

The associations between enteric pathogenic parasites and growth in infants in São Tomé were explored using a refined anthropometric approach to recognize early growth faltering. A birth cohort study was conducted with follow-up to 24 months of age. Microscopic examination for protozoa and soil-transmitted helminths was performed. Anthropometric assessments included: z-scores for weight-for-length (WLZ), length-for-age (LAZ), weight (WAVZ) and length velocities (LAVZ), length-for-age difference (LAD), and wasting and stunting risk (≤−1 SD). Generalized additive mixed effects regression models were used to explore the associations between anthropometric parameters and enteric parasitic infections and cofactors. A total of 475 infants were enrolled, and 282 completed the study. The great majority of infants were asymptomatic. Giardia lamblia was detected in 35.1% of infants in at least one stool sample, helminths in 30.4%, and Cryptosporidium spp. in 14.7%. Giardia lamblia and helminth infections were significantly associated with mean decreases of 0.10 in LAZ and 0.32 in LAD, and of 0.16 in LAZ and 0.48 in LAD, respectively. Cryptosporidium spp. infection was significantly associated with a mean decrease of 0.43 in WAVZ and 0.55 in LAVZ. The underestimated association between subclinical parasitic enteric infections and mild growth faltering in infants should be addressed in public health policies. PMID:29621166

The Protozoa, A Kingdom By Default?

ERIC Educational Resources Information Center

Blackwell, Will H.; Powell, Martha J.

2001-01-01

Changes in the concepts of kingdoms of organisms are substantial and Protozoa is loosely characterized. Presents a case explaining how Protozoa interface with other kingdoms of organisms now recognized. (Contains 55 references.) (ASK)

Influence of rumen protozoa on methane emission in ruminants: a meta-analysis approach.

PubMed

Guyader, J; Eugène, M; Nozière, P; Morgavi, D P; Doreau, M; Martin, C

2014-11-01

A meta-analysis was conducted to evaluate the effects of protozoa concentration on methane emission from ruminants. A database was built from 59 publications reporting data from 76 in vivo experiments. The experiments included in the database recorded methane production and rumen protozoa concentration measured on the same groups of animals. Quantitative data such as diet chemical composition, rumen fermentation and microbial parameters, and qualitative information such as methane mitigation strategies were also collected. In the database, 31% of the experiments reported a concomitant reduction of both protozoa concentration and methane emission (g/kg dry matter intake). Nearly all of these experiments tested lipids as methane mitigation strategies. By contrast, 21% of the experiments reported a variation in methane emission without changes in protozoa numbers, indicating that methanogenesis is also regulated by other mechanisms not involving protozoa. Experiments that used chemical compounds as an antimethanogenic treatment belonged to this group. The relationship between methane emission and protozoa concentration was studied with a variance-covariance model, with experiment as a fixed effect. The experiments included in the analysis had a within-experiment variation of protozoa concentration higher than 5.3 log10 cells/ml corresponding to the average s.e.m. of the database for this variable. To detect potential interfering factors for the relationship, the influence of several qualitative and quantitative secondary factors was tested. This meta-analysis showed a significant linear relationship between methane emission and protozoa concentration: methane (g/kg dry matter intake)=-30.7+8.14×protozoa (log10 cells/ml) with 28 experiments (91 treatments), residual mean square error=1.94 and adjusted R 2=0.90. The proportion of butyrate in the rumen positively influenced the least square means of this relationship.

Effects of altered temperature and precipitation on desert protozoa associated with biological soil crusts

USGS Publications Warehouse

Darby, B.J.; Housman, D.C.; Zaki, A.M.; Shamout, Y.; Adl, S.M.; Belnap, J.; Neher, D.A.

2006-01-01

Biological soil crusts are diverse assemblages of bacteria, cyanobacteria, algae, fungi, lichens, and mosses that cover much of arid land soils. The objective of this study was to quantify protozoa associated with biological soil crusts and test the response of protozoa to increased temperature and precipitation as is predicted by some global climate models. Protozoa were more abundant when associated with cyanobacteria/lichen crusts than with cyanobacteria crusts alone. Amoebae, flagellates, and ciliates originating from the Colorado Plateau desert (cool desert, primarily winter precipitation) declined 50-, 10-, and 100-fold, respectively, when moved in field mesocosms to the Chihuahuan Desert (hot desert, primarily summer rain). However, this was not observed in protozoa collected from the Chihuahuan Desert and moved to the Sonoran desert (hot desert, also summer rain, but warmer than Chihuahuan Desert). Protozoa in culture began to encyst at 37??C. Cysts survived the upper end of daily temperatures (37-55??C), and could be stimulated to excyst if temperatures were reduced to 15??C or lower. Results from this study suggest that cool desert protozoa are influenced negatively by increased summer precipitation during excessive summer temperatures, and that desert protozoa may be adapted to a specific desert's temperature and precipitation regime. ?? 2006 by the International Society of Protistologists.

Protozoa enhance foraging efficiency of arbuscular mycorrhizal fungi for mineral nitrogen from organic matter in soil to the benefit of host plants.

PubMed

Koller, Robert; Rodriguez, Alia; Robin, Christophe; Scheu, Stefan; Bonkowski, Michael

2013-07-01

Dead organic matter (OM) is a major source of nitrogen (N) for plants. The majority of plants support N uptake by symbiosis with arbuscular mycorrhizal (AM) fungi. Mineralization of N is regulated by microfauna, in particular, protozoa grazing on bacteria. We hypothesized that AM fungi and protozoa interactively facilitate plant N nutrition from OM. In soil systems consisting of an OM patch and a root compartment, plant N uptake and consequences for plant carbon (C) allocation were investigated using stable isotopes. Protozoa mobilized N by consuming bacteria, and the mobilized N was translocated via AM fungi to the host plant. The presence of protozoa in both the OM and root compartment stimulated photosynthesis and the translocation of C from the host plant via AM fungi into the OM patch. This stimulated microbial activity in the OM patch, plant N uptake from OM and doubled plant growth. The results indicate that protozoa increase plant growth by both mobilization of N from OM and by protozoa-root interactions, resulting in increased C allocation to roots and into the rhizosphere, thereby increasing plant nutrient exploitation. Hence, mycorrhizal plants need to interact with protozoa to fully exploit N resources from OM. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

Clinical and immunological characteristics associated with the presence of protozoa in sputum smears.

PubMed

Martínez-Girón, Rafael; van Woerden, Hugo Cornelis

2013-01-01

The objective of this study is to assess the relationship between protozoa in spontaneously expectorated sputum samples and a range of clinical and immunological variables. Clinical details including age, gender, smoking status, and use of oral or inhaled steroids were recorded for a cohort of 199 patients whose spontaneously expectorated sputum samples were submitted to a Cytology Laboratory in Spain between January 2005 and December 2006. Slides were scanned for protozoa under light microscopy and scanned for monocytes/small macrophages highlighted by immunocytochemistry (CD68 monoclonal antibody). One hundred ninety-one patients provided adequate sputum samples, of whom 70 had protozoa in their sputum. There was a strong relationship between the presence of protozoa and monocytes/small macrophages identified under light microscopy (P < 0.001). A binary logistic regression model also indicated a relationship between protozoa and both smoking status and steroid use. The diagnoses in those with protozoa included infection (including tuberculosis), chronic obstructive pulmonary disease (COPD), lung fibrosis, asthma, chronic liver disease, immunosuppression, cancer, pancreatic or renal disease, heart failure, and AIDS. The identified association between protozoa and monocytes/small macrophages in sputum suggests an immune response and warrants further investigation to clarify whether or not these organisms have any pathological significance in this wide range of conditions. Copyright © 2011 Wiley Periodicals, Inc.

Visceral leishmaniasis with Roth spots

PubMed Central

Meena, Jagdish; Juneja, Monica; Mishra, Devendra; Vats, Pallavi; Pawaria, Arti

2014-01-01

Visceral leishmaniasis (VL) is caused by the protozoan parasite Leishmania donovani and transmitted by the bite of infected sandfly Phlebotomus argentipes. The protozoa is obliged intracellularly and causes a wide spectrum of clinical syndromes: VL (‘kala azar’), cutaneous leishmaniasis and mucocutaneous leishmaniasis (espundia). Kala azar is the most aggressive form and if untreated causes high mortality. Here, we describe a case of VL that presented to us with high-grade fever and found to have Roth spots that were resolved after 15 days of therapy. PMID:25988048

Airborne pathogens from dairy manure aerial irrigation and the human health risk

USGS Publications Warehouse

Borchardt, Mark A.; Burch, Tucker R

2016-01-01

Dairy manure, like the fecal excrement from any domesticated or wild animal, can contain pathogens capable of infecting humans and causing illness or even death. Pathogens in dairy manure can be broadly divided into categories of taxonomy or infectiousness. Dividing by taxonomy there are three pathogen groups in dairy manure: viruses (e.g., bovine rotavirus), bacteria (e.g., Salmonella species), and protozoa (e.g., Cryptosporidium parvum). There are two categories of infectiousness for pathogens found in animals: those that are zoonotic and those that are not. A zoonotic pathogen is one that can infect both human and animal hosts. Some zoonotic pathogens found in dairy manure cause illness in both hosts (e.g., Salmonella) while other zoonotic pathogens, like Escherichia coli O157:H7, (enterohemorrhagic E. coli (EHEC)) cause illness only in humans. As a general rule, the gastrointestinal viruses found in dairy manure are not zoonotic. While there are exceptions (e.g., rare reports of bovine rotavirus infecting children), for the most part the viruses in dairy manure are not a human health concern. The primary concerns are the zoonotic bacteria and protozoa in dairy manure.

Besnoitia neotomofelis n. sp. (Protozoa: Apicomplexa) from the southern plains woodrat (Neotoma micropus)

USDA-ARS?s Scientific Manuscript database

Certain species of the protozoan genus Besnoitia cause clinical disease in livestock and wildlife. In the present paper a new species, Besnoitia neotomofelis is described from the southern planes woodrat (Neotoma micropus). The parasite was detected by bioassay of woodrat tissues in out bred Swiss W...

Expression of avian beta-defensins in the intestine of Eimeria-challenged chickens

USDA-ARS?s Scientific Manuscript database

Avian coccidiosis is caused by the intracellular protozoa Eimeria. The site of invasion and lesions in the intestine is species-specific; for example, E. acervulina mainly affects the duodenum, E. maxima the jejunum, and E. tenella the ceca. Lesions in the intestinal mucosa reduce feed efficiency a...

Asymptomatic Effluent Protozoa Colonization in Peritoneal Dialysis Patients.

PubMed

Simões-Silva, Liliana; Correia, Inês; Barbosa, Joana; Santos-Araujo, Carla; Sousa, Maria João; Pestana, Manuel; Soares-Silva, Isabel; Sampaio-Maia, Benedita

Currently, chronic kidney disease (CKD) is a global health problem. Considering the impaired immunity of CKD patients, the relevance of infection in peritoneal dialysis (PD), and the increased prevalence of parasites in CKD patients, protozoa colonization was evaluated in PD effluent from CKD patients undergoing PD. Overnight PD effluent was obtained from 49 asymptomatic stable PD patients. Protozoa analysis was performed microscopically by searching cysts and trophozoites in direct wet mount of PD effluent and after staining smears. Protozoa were found in PD effluent of 10.2% of evaluated PD patients, namely Blastocystis hominis, in 2 patients, and Entamoeba sp., Giardia sp., and Endolimax nana in the other 3 patients, respectively. None of these patients presented clinical signs or symptoms of peritonitis at the time of protozoa screening. Our results demonstrate that PD effluent may be susceptible to asymptomatic protozoa colonization. The clinical impact of this finding should be further investigated. Copyright © 2016 International Society for Peritoneal Dialysis.

Tick-borne protozoa

USDA-ARS?s Scientific Manuscript database

Tick-borne protozoa impose a significant health burden on humans and animals throughout the world. The virulence of tick-borne protozoa, and the geographic distribution of their tick vectors and vertebrate hosts remain in flux as they adapt to changing environmental and climatic conditions. Babesios...

Drug Targets and Mechanisms of Resistance in the Anaerobic Protozoa

PubMed Central

Upcroft, Peter; Upcroft, Jacqueline A.

2001-01-01

The anaerobic protozoa Giardia duodenalis, Trichomonas vaginalis, and Entamoeba histolytica infect up to a billion people each year. G. duodenalis and E. histolytica are primarily pathogens of the intestinal tract, although E. histolytica can form abscesses and invade other organs, where it can be fatal if left untreated. T. vaginalis infection is a sexually transmitted infection causing vaginitis and acute inflammatory disease of the genital mucosa. T. vaginalis has also been reported in the urinary tract, fallopian tubes, and pelvis and can cause pneumonia, bronchitis, and oral lesions. Respiratory infections can be acquired perinatally. T. vaginalis infections have been associated with preterm delivery, low birth weight, and increased mortality as well as predisposing to human immunodeficiency virus infection, AIDS, and cervical cancer. All three organisms lack mitochondria and are susceptible to the nitroimidazole metronidazole because of similar low-redox-potential anaerobic metabolic pathways. Resistance to metronidazole and other drugs has been observed clinically and in the laboratory. Laboratory studies have identified the enzyme that activates metronidazole, pyruvate:ferredoxin oxidoreductase, to its nitroso form and distinct mechanisms of decreasing drug susceptibility that are induced in each organism. Although the nitroimidazoles have been the drug family of choice for treating the anaerobic protozoa, G. duodenalis is less susceptible to other antiparasitic drugs, such as furazolidone, albendazole, and quinacrine. Resistance has been demonstrated for each agent, and the mechanism of resistance has been investigated. Metronidazole resistance in T. vaginalis is well documented, and the principal mechanisms have been defined. Bypass metabolism, such as alternative oxidoreductases, have been discovered in both organisms. Aerobic versus anaerobic resistance in T. vaginalis is discussed. Mechanisms of metronidazole resistance in E. histolytica have recently been investigated using laboratory-induced resistant isolates. Instead of downregulation of the pyruvate:ferredoxin oxidoreductase and ferredoxin pathway as seen in G. duodenalis and T. vaginalis, E. histolytica induces oxidative stress mechanisms, including superoxide dismutase and peroxiredoxin. The review examines the value of investigating both clinical and laboratory-induced syngeneic drug-resistant isolates and dissection of the complementary data obtained. Comparison of resistance mechanisms in anaerobic bacteria and the parasitic protozoa is discussed as well as the value of studies of the epidemiology of resistance. PMID:11148007

Low ambient temperature elevates plasma triiodothyronine concentrations while reducing digesta mean retention time and methane yield in sheep.

PubMed

Barnett, M C; McFarlane, J R; Hegarty, R S

2015-06-01

Ruminant methane yield (MY) is positively correlated with mean retention time (MRT) of digesta. The hormone triiodothyronine (T3 ), which is negatively correlated with ambient temperature, is known to influence MRT. It was hypothesised that exposing sheep to low ambient temperatures would increase plasma T3 concentration and decrease MRT of digesta within the rumen of sheep, resulting in a reduction of MY. To test this hypothesis, six Merino sheep were exposed to two different ambient temperatures (cold treatment, 9 ± 1 °C; warm control 26 ± 1 °C). The effects on MY, digesta MRT, plasma T3 concentration, CO2 production, DM intake, DM digestibility, change in body weight (BW), rumen volatile fatty acid (VFA) concentrations, estimated microbial protein output, protozoa abundance, wool growth, water intake, urine output and rectal temperature were studied. Cold treatment resulted in a reduction in MY (p < 0.01); digesta MRT in rumen (p < 0.01), hindgut (p = 0.01) and total digestive tract (p < 0.01); protozoa abundance (p < 0.05); and water intake (p < 0.001). Exposure to cold temperature increased plasma T3 concentration (p < 0.05), CO2 production (p = 0.01), total VFA concentrations (p = 0.03) and estimated microbial output from the rumen (p = 0.03). The rate of wool growth increased (p < 0.01) due to cold treatment, but DM intake, DM digestibility and BW change were not affected. The results suggest that exposure of sheep to cold ambient temperatures reduces digesta retention time in the gastrointestinal tract, leading to a reduction in enteric methane yield. Further research is warranted to determine whether T3 could be used as an indirect selection tool for genetic selection of low enteric methane-producing ruminants. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Further assessment of the protozoal contribution to the nutrition of the ruminant animal.

PubMed

Hook, Sarah E; France, James; Dijkstra, Jan

2017-03-07

The flow of protozoa from the reticulo-rumen is lower than expected, due to ability of protozoa to prevent washout through sequestration on feed particles and the rumen epithelium. In order to estimate the distribution of protozoa within the reticulo-rumen and passage to the omasum, Czerkawski (1987) developed a model containing pools for the rumen liquid phase, rumen solid phase, and the omasum. This model was used to estimate loss of protozoa in the omasum as well as the amount of protozoal protein available to the animal in the lower gut. A number of assumptions were incorporated into the model, some of which appear unsupported by current research. This paper represents an update, revision, and re-evaluation of Czerkawski's model, where the assumptions that all protozoa in the 'attached' phase are in solid digesta, and that protozoa only leave the rumen in the liquid, have been relaxed. Therefore, the revised model allows for sequestration of protozoa on the rumen epithelium and protozoal passage with particulate outflow. Using experimental observations with inputs within biological limits, the revised model and Czerkawski's original model were verified. The effect of diet on the model was then assessed using inputs from a 100% forage diet and a 35-65% concentrate diet. The extent of sequestration was also varied from complete sequestration, to partial sequestration, and no sequestration. A sensitivity analysis was conducted through a linear regression of perturbed mean inputs versus outputs. The results from the revised model indicate that within the reticulo-rumen, the concentrate diet has a greater fractional flow rate of protozoa from the liquid to solid phase, but a lesser fractional flow rate back to the liquid phase, compared to the forage diet. As well, the concentrate diet has a slower net growth rate of protozoa in the attached phase, compared to the forage diet. In the omasum, the forage diet has a less negative net growth rate, compared to the concentrate diet. The forage diet was also associated with smaller loss of protozoa from the omasum. There are limited data from the omasum to be incorporated into the revised model, especially for quantity of protozoa in the omasum. Further research on quantification of protozoa in the omasum could strengthen the predictions made by the model. Despite this, the revised model found a loss of protozoa in the omasum similar to that suggested by Czerkawski's original model 65-73% versus 66%. The revised model results indicate that efforts to increase protozoal flow to the duodenum should focus on reduced sequestration and increased outflow rate from the rumen, although more research is needed to quantify protozoa in the omasum, and to investigate the role of sequestration onto the wall of the reticulo-rumen. Copyright © 2016 Elsevier Ltd. All rights reserved.

Repertoire of free-living protozoa in contact lens solutions.

PubMed

Bouchoucha, Ibtissem; Aziz, Aurore; Hoffart, Louis; Drancourt, Michel

2016-10-29

The repertoire of free-living protozoa in contact lens solutions is poorly known despite the fact that such protozoa may act as direct pathogens and may harbor intra-cellular pathogens. Between 2009 and 2014, the contact lens solutions collected from patients presenting at our Ophthalmology Department for clinically suspected keratitis, were cultured on non-nutrient agar examined by microscope for the presence of free-living protozoa. All protozoa were identified by 18S rRNA gene sequencing. A total of 20 of 233 (8.6 %) contact lens solution specimens collected from 16 patients were cultured. Acanthamoeba amoeba in 16 solutions (80 %) collected from 12 patients and Colpoda steini, Cercozoa sp., Protostelium sp. and a eukaryotic more closely related to Vermamoeba sp., were each isolated in one solution. Cercozoa sp., Colpoda sp., Protostelium sp. and Vermamoeba sp. are reported for the first time as contaminating contact lens solutions. The repertoire of protozoa in contact lens solutions is larger than previously known.

Expression of digestive enzymes and nutrient transporters in Eimeria acervulina-challenged layers and broilers

USDA-ARS?s Scientific Manuscript database

Avian coccidiosis is a disease caused by the intestinal protozoa Eimeria. Eimeria-infected chickens develop lesions in the intestinal mucosa, which result in reduced feed efficiency and body weight gain. This growth reduction may be due to changes in expression of digestive enzymes and nutrient tran...

Toxicity and repellency of plant essential oils against the arthropod disease vectors Phlebotomus papatasi and Ixodes scapularis

USDA-ARS?s Scientific Manuscript database

The sand fly Phlebotomus papatasi is an important blood feeder and the main vector of the trypanosomatid protozoa Leishmania major, which causes leishmaniasis in parts of the Afro-Eurasian region. The black- legged tick Ixodes scapularis is the primary tick vector of the bacterium Borrelia burgdorfe...

STRAIN DIFFERENTIATION AND VIABILITY/INFECTIVITY DETERMINATION BY MALDI/MS AND ESI/MS OF VIRUSES, BACTERIA, AND PROTOZOA

EPA Science Inventory

Over the last three decades, the Centers for Disease Control and Prevention (CDC) and the U.S. EPA have collected and reported data relating to occurrences and causes of waterborne-disease outbreaks in the United States. During 1997 through 1998, 13 states reported 17 outbreaks ...

Accumulation of Reserve Carbohydrate by Rumen Protozoa and Bacteria in Competition for Glucose

PubMed Central

Denton, Bethany L.; Diese, Leanne E.; Firkins, Jeffrey L.

2014-01-01

The aim of this study was to determine if rumen protozoa could form large amounts of reserve carbohydrate compared to the amounts formed by bacteria when competing for glucose in batch cultures. We separated large protozoa and small bacteria from rumen fluid by filtration and centrifugation, recombined equal protein masses of each group into one mixture, and subsequently harvested (reseparated) these groups at intervals after glucose dosing. This method allowed us to monitor reserve carbohydrate accumulation of protozoa and bacteria individually. When mixtures were dosed with a moderate concentration of glucose (4.62 or 5 mM) (n = 2 each), protozoa accumulated large amounts of reserve carbohydrate; 58.7% (standard error of the mean [SEM], 2.2%) glucose carbon was recovered from protozoal reserve carbohydrate at time of peak reserve carbohydrate concentrations. Only 1.7% (SEM, 2.2%) was recovered in bacterial reserve carbohydrate, which was less than that for protozoa (P < 0.001). When provided a high concentration of glucose (20 mM) (n = 4 each), 24.1% (SEM, 2.2%) of glucose carbon was recovered from protozoal reserve carbohydrate, which was still higher (P = 0.001) than the 5.0% (SEM, 2.2%) glucose carbon recovered from bacterial reserve carbohydrate. Our novel competition experiments directly demonstrate that mixed protozoa can sequester sugar away from bacteria by accumulating reserve carbohydrate, giving protozoa a competitive advantage and stabilizing fermentation in the rumen. Similar experiments could be used to investigate the importance of starch sequestration. PMID:25548053

Testing protozoacidal activity of ligand-lytic peptides against termite gut protozoa in vitro (protozoa culture) and in vivo (microinjection into termite hindgut).

PubMed

Husseneder, Claudia; Sethi, Amit; Foil, Lane; Delatte, Jennifer

2010-12-29

We are developing a novel approach to subterranean termite control that would lead to reduced reliance on the use of chemical pesticides. Subterranean termites are dependent on protozoa in the hindguts of workers to efficiently digest wood. Lytic peptides have been shown to kill a variety of protozoan parasites (Mutwiri et al. 2000) and also protozoa in the gut of the Formosan subterranean termite, Coptotermes formosanus (Husseneder and Collier 2009). Lytic peptides are part of the nonspecific immune system of eukaryotes, and destroy the membranes of microorganisms (Leuschner and Hansel 2004). Most lytic peptides are not likely to harm higher eukaryotes, because they do not affect the electrically neutral cholesterol-containing cell membranes of higher eukaryotes (Javadpour et al. 1996). Lytic peptide action can be targeted to specific cell types by the addition of a ligand. For example, Hansel et al. (2007) reported that lytic peptides conjugated with cancer cell membrane receptor ligands could be used to destroy breast cancer cells, while lytic peptides alone or conjugated with non-specific peptides were not effective. Lytic peptides also have been conjugated to human hormones that bind to receptors on tumor cells for targeted destruction of prostate and testicular cancer cells (Leuschner and Hansel 2004). In this article we present techniques used to demonstrate the protozoacidal activity of a lytic peptide (Hecate) coupled to a heptapeptide ligand that binds to the surface membrane of protozoa from the gut of the Formosan subterranean termite. These techniques include extirpation of the gut from termite workers, anaerobic culture of gut protozoa (Pseudotrichonympha grassii, Holomastigotoides hartmanni,Spirotrichonympha leidyi), microscopic confirmation that the ligand marked with a fluorescent dye binds to the termite gut protozoa and other free-living protozoa but not to bacteria or gut tissue. We also demonstrate that the same ligand coupled to a lytic peptide efficiently kills termite gut protozoa in vitro (protozoa culture) and in vivo (microinjection into hindgut of workers), but is less bacteriacidal than the lytic peptide alone. The loss of protozoa leads to the death of the termites in less than two weeks. In the future, we will genetically engineer microorganisms that can survive in the termite hindgut and spread through a termite colony as "Trojan Horses" to express ligand-lytic peptides that would kill the protozoa in the termite gut and subsequently kill the termites in the colony. Ligand-lytic peptides also could be useful for drug development against protozoan parasites.

Systemic Scuticociliatosis (Philasterides dicentrarchi) in sharks.

PubMed

Stidworthy, M F; Garner, M M; Bradway, D S; Westfall, B D; Joseph, B; Repetto, S; Guglielmi, E; Schmidt-Posthaus, H; Thornton, S M

2014-05-01

Scuticociliatosis is an economically important, frequently fatal disease of marine fish in aquaculture, caused by histophagous ciliated protozoa in the subclass Scuticociliatida of the phylum Ciliophora. A rapidly lethal systemic scuticociliate infection is described that affected aquarium-captive zebra sharks (Stegostoma fasciatum), Port Jackson sharks (Heterodontus portusjacksoni), and a Japanese horn shark (Heterodontus japonicus). Animals died unexpectedly or after a brief period of lethargy or behavioral abnormality. Gross findings included necrohemorrhagic hepatitis and increased volumes of celomic fluid. Histologically, 1 or more of a triad of necrotizing hepatitis, necrotizing meningoencephalitis, and thrombosing branchitis were seen in all cases, with necrotizing vasculitis or intravascular fibrinocellular thrombi. Lesions contained variably abundant invading ciliated protozoa. Molecular identification by polymerase chain reaction from formalin-fixed tissues identified these as the scuticociliate Philasterides dicentrarchi (syn. Miamiensis avidus), a novel and potentially emergent pathogen in sharks.

[Prevalence of intestinal microsporidia and other intestinal parasites in hiv positive patients from Maracaibo, Venezuela].

PubMed

Rivero-Rodríguez, Zulbey; Hernández, Amparo; Bracho, Ángela; Salazar, Solneumar; Villalobos, Rafael

2013-01-01

To detect the presence of microsporidia and other enteric parasites in patients with HIVAIDS of the Autonomous Services University Hospital of Maracaibo (SAHUM), where there are no previous studies in this field. Fecal samples were analyzed by means of direct exam, concetration method with formal-ether, Kinyoun coloration and fast Gram-Chromotrope coloration. Separate PCR were perfomed to differentiate Entamoeba histolytica and Entamoeba dispar , when the E. histolytica/E. dispar complex was observed in the microscope. Information on the patient was obtained trough clinical history. Of 56 individuals that participated, 38 (67.86%) presented some commensal parasite and/ or pathogenic species in their fecal sample. Carriers of pathogenic species were predominat (26/38). Protozoa such as Isospora belli protozoa (17.65%), Blastocystis spp. (17.65%), Cryptosporidium spp. (7.84%), E. histolytica/E. dispar (5.88%), Entamoeba coli (3.92%), Giardia lamblia (3.92%), Endolimax nana (3.92%), Cyclospora cayetanensis (3.92%), and Chilomastix mesnilli (1.96%) were diagnosed. Among the helminths, Ascaris lumbricoides, Trichuris trichiura and Strongyloides stercoralis , had a percentage of 27.27% each, and Hymenolepis nana , 18.18%. Entamoeba histolytica was only detected in one of three cases presenting complex microscopic examination. By Gram-chromotrope, 17 samples showed spores of the Microsporidia phylum, equivalent to 33.33% prevalence. Microsporidia may be first prevalente in HIV positive patients when specific diagnostic techniques are used.

Environmental (Saprozoic) Pathogens of Engineered Water Systems: Understanding Their Ecology for Risk Assessment and Management

PubMed Central

Ashbolt, Nicholas J.

2015-01-01

Major waterborne (enteric) pathogens are relatively well understood and treatment controls are effective when well managed. However, water-based, saprozoic pathogens that grow within engineered water systems (primarily within biofilms/sediments) cannot be controlled by water treatment alone prior to entry into water distribution and other engineered water systems. Growth within biofilms or as in the case of Legionella pneumophila, primarily within free-living protozoa feeding on biofilms, results from competitive advantage. Meaning, to understand how to manage water-based pathogen diseases (a sub-set of saprozoses) we need to understand the microbial ecology of biofilms; with key factors including biofilm bacterial diversity that influence amoebae hosts and members antagonistic to water-based pathogens, along with impacts from biofilm substratum, water temperature, flow conditions and disinfectant residual—all control variables. Major saprozoic pathogens covering viruses, bacteria, fungi and free-living protozoa are listed, yet today most of the recognized health burden from drinking waters is driven by legionellae, non-tuberculous mycobacteria (NTM) and, to a lesser extent, Pseudomonas aeruginosa. In developing best management practices for engineered water systems based on hazard analysis critical control point (HACCP) or water safety plan (WSP) approaches, multi-factor control strategies, based on quantitative microbial risk assessments need to be developed, to reduce disease from largely opportunistic, water-based pathogens. PMID:26102291

Accumulation of reserve carbohydrate by rumen protozoa and bacteria in competition for glucose.

PubMed

Denton, Bethany L; Diese, Leanne E; Firkins, Jeffrey L; Hackmann, Timothy J

2015-03-01

The aim of this study was to determine if rumen protozoa could form large amounts of reserve carbohydrate compared to the amounts formed by bacteria when competing for glucose in batch cultures. We separated large protozoa and small bacteria from rumen fluid by filtration and centrifugation, recombined equal protein masses of each group into one mixture, and subsequently harvested (reseparated) these groups at intervals after glucose dosing. This method allowed us to monitor reserve carbohydrate accumulation of protozoa and bacteria individually. When mixtures were dosed with a moderate concentration of glucose (4.62 or 5 mM) (n = 2 each), protozoa accumulated large amounts of reserve carbohydrate; 58.7% (standard error of the mean [SEM], 2.2%) glucose carbon was recovered from protozoal reserve carbohydrate at time of peak reserve carbohydrate concentrations. Only 1.7% (SEM, 2.2%) was recovered in bacterial reserve carbohydrate, which was less than that for protozoa (P < 0.001). When provided a high concentration of glucose (20 mM) (n = 4 each), 24.1% (SEM, 2.2%) of glucose carbon was recovered from protozoal reserve carbohydrate, which was still higher (P = 0.001) than the 5.0% (SEM, 2.2%) glucose carbon recovered from bacterial reserve carbohydrate. Our novel competition experiments directly demonstrate that mixed protozoa can sequester sugar away from bacteria by accumulating reserve carbohydrate, giving protozoa a competitive advantage and stabilizing fermentation in the rumen. Similar experiments could be used to investigate the importance of starch sequestration. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

[Effects of adding straw carbon source to root knot nematode diseased soil on soil microbial biomass and protozoa abundance].

PubMed

Zhang, Si-Hui; Lian, Jian-Hong; Cao, Zhi-Ping; Zhao, Li

2013-06-01

A field experiment with successive planting of tomato was conducted to study the effects of adding different amounts of winter wheat straw (2.08 g x kg(-1), 1N; 4.16 g x kg(-1), 2N; and 8.32 g x kg(-1), 4N) to the soil seriously suffered from root knot nematode disease on the soil microbial biomass and protozoa abundance. Adding straw carbon source had significant effects on the contents of soil microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) and the abundance of soil protozoa, which all decreased in the order of 4N > 2N > 1N > CK. The community structure of soil protozoa also changed significantly under straw addition. In the treatments with straw addition, the average proportion of fagellate, amoeba, and ciliates accounted for 36.0%, 59.5%, and 4.5% of the total protozoa, respectively. Under the same adding amounts of wheat straw, there was an increase in the soil MBC and MBN contents, MBC/MBN ratio, and protozoa abundance with increasing cultivation period.

Laboratory-Acquired Parasitic Infections from Accidental Exposures

PubMed Central

Herwaldt, Barbara L.

2001-01-01

Parasitic diseases are receiving increasing attention in developed countries in part because of their importance in travelers, immigrants, and immunocompromised persons. The main purpose of this review is to educate laboratorians, the primary readership, and health care workers, the secondary readership, about the potential hazards of handling specimens that contain viable parasites and about the diseases that can result. This is accomplished partly through discussion of the occupationally acquired cases of parasitic infections that have been reported, focusing for each case on the type of accident that resulted in infection, the length of the incubation period, the clinical manifestations that developed, and the means by which infection was detected. The article focuses on the cases of infection with the protozoa that cause leishmaniasis, malaria, toxoplasmosis, Chagas' disease (American trypanosomiasis), and African trypanosomiasis. Data about 164 such cases are discussed, as are data about cases caused by intestinal protozoa and by helminths. Of the 105 case-patients infected with blood and tissue protozoa who either recalled an accident or for whom the likely route of transmission could be presumed, 47 (44.8%) had percutaneous exposure via a contaminated needle or other sharp object. Some accidents were directly linked to poor laboratory practices (e.g., recapping a needle or working barehanded). To decrease the likelihood of accidental exposures, persons who could be exposed to pathogenic parasites must be thoroughly instructed in safety precautions before they begin to work and through ongoing training programs. Protocols should be provided for handling specimens that could contain viable organisms, using protective clothing and equipment, dealing with spills of infectious organisms, and responding to accidents. Special care should be exercised when using needles and other sharp objects. PMID:11585780

Global climate and infectious disease: The cholera paradigm

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colwell, R.R.

1996-12-20

Historically, infectious diseases have had a profound effect on human populations, including their evolution and cultural development. Despite significant advances in medical science, infectious diseases continue to impact human populations in many parts of the world. Emerging diseases are considered to be those infections that either are newly appearing in the population or are rapidly increasing in incidence or expanding in geographic range. Emergence of disease is not a simple phenomenon, mainly because infectious diseases are dynamic. Most new infections are not caused by truly new pathogens but are microorganisms (viruses, bacteria, fungi, protozoa, and helminths) that find a newmore » way to enter a susceptible host and are newly recognized because of recently developed, sensitive techniques. Human activities drive emergence of disease and a variety of social, economic, political, climatic, technological, and environmental factors can shape the pattern of a disease and influence its emergence into populations. For example, travel affects emergence of disease, and human migrations have been the main source of epidemics throughout history. Trade caravans, religious pilgrimage, and military campaigns facilitated the spread of plague, smallpox, and cholera. Global travel is a fact of modern life and, equally so, the continued evolution of microorganisms; therefore, new infections will continue to emerge, and known infections will change in distribution, frequency, and severity. 88 refs., 1 fig.« less

Loop-mediated Isothermal Amplification (LAMP) Assays for the Species-specific Detection of Eimeria that Infect Chickens

PubMed Central

Barkway, Christopher P.; Pocock, Rebecca L.; Vrba, Vladimir; Blake, Damer P.

2015-01-01

Eimeria species parasites, protozoa which cause the enteric disease coccidiosis, pose a serious threat to the production and welfare of chickens. In the absence of effective control clinical coccidiosis can be devastating. Resistance to the chemoprophylactics frequently used to control Eimeria is common and sub-clinical infection is widespread, influencing feed conversion ratios and susceptibility to other pathogens such as Clostridium perfringens. Despite the availability of polymerase chain reaction (PCR)-based tools, diagnosis of Eimeria infection still relies almost entirely on traditional approaches such as lesion scoring and oocyst morphology, but neither is straightforward. Limitations of the existing molecular tools include the requirement for specialist equipment and difficulties accessing DNA as template. In response a simple field DNA preparation protocol and a panel of species-specific loop-mediated isothermal amplification (LAMP) assays have been developed for the seven Eimeria recognised to infect the chicken. We now provide a detailed protocol describing the preparation of genomic DNA from intestinal tissue collected post-mortem, followed by setup and readout of the LAMP assays. Eimeria species-specific LAMP can be used to monitor parasite occurrence, assessing the efficacy of a farm’s anticoccidial strategy, and to diagnose sub-clinical infection or clinical disease with particular value when expert surveillance is unavailable. PMID:25741643

Loop-mediated isothermal amplification (LAMP) assays for the species-specific detection of Eimeria that infect chickens.

PubMed

Barkway, Christopher P; Pocock, Rebecca L; Vrba, Vladimir; Blake, Damer P

2015-02-20

Eimeria species parasites, protozoa which cause the enteric disease coccidiosis, pose a serious threat to the production and welfare of chickens. In the absence of effective control clinical coccidiosis can be devastating. Resistance to the chemoprophylactics frequently used to control Eimeria is common and sub-clinical infection is widespread, influencing feed conversion ratios and susceptibility to other pathogens such as Clostridium perfringens. Despite the availability of polymerase chain reaction (PCR)-based tools, diagnosis of Eimeria infection still relies almost entirely on traditional approaches such as lesion scoring and oocyst morphology, but neither is straightforward. Limitations of the existing molecular tools include the requirement for specialist equipment and difficulties accessing DNA as template. In response a simple field DNA preparation protocol and a panel of species-specific loop-mediated isothermal amplification (LAMP) assays have been developed for the seven Eimeria recognised to infect the chicken. We now provide a detailed protocol describing the preparation of genomic DNA from intestinal tissue collected post-mortem, followed by setup and readout of the LAMP assays. Eimeria species-specific LAMP can be used to monitor parasite occurrence, assessing the efficacy of a farm's anticoccidial strategy, and to diagnose sub-clinical infection or clinical disease with particular value when expert surveillance is unavailable.

Intravital Computer Morphometry on Protozoa: A Method for Monitoring of the Morphofunctional Disorders in Cells Exposed in the Cell Phone Communication Electromagnetic Field.

PubMed

Uskalova, D V; Igolkina, Yu V; Sarapultseva, E I

2016-08-01

Morphofunctional disorders in unicellular aquatic protozoa - Spirostomum ambiguum infusorians after 30-, 60-, and 360-min exposure in electromagnetic field at a radiation frequency of 1 GHz and energy flow density of 50 μW/cm(2) were analyzed by intravital computer morphometry. Significant disorders in morphometric values correlated with low mobility of the protozoa. The results suggested the use of intravital computer morphometry on the protozoa for early diagnosis of radiation-induced effects of the mobile communication electromagnetic field, for example, low mobility of spermatozoa.

Impact of transition from microscopy to molecular screening for detection of intestinal protozoa in Dutch patients.

PubMed

Svraka-Latifovic, S; Bouter, S; Naus, H; Bakker, L J; Timmerman, C P; Dorigo-Zetsma, J W

2014-11-01

Detection of intestinal protozoa by PCR methods has been described as being sensitive and specific, and as improving the diagnostic yield. Here we present the outcome of the transition from microscopy to molecular screening for detection of a select group of intestinal protozoa in faeces in our laboratory. Introduction of molecular screening for intestinal protozoa resulted in higher sensitivity, reduced hands-on-time, reduced time-to-results, leading to improved diagnostic efficiency. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.

Study of methanogen communities associated with different rumen protozoal populations

PubMed Central

Belanche, Alejandro; de la Fuente, Gabriel; Newbold, Charles J

2014-01-01

Protozoa-associated methanogens (PAM) are considered one of the most active communities in the rumen methanogenesis. This experiment investigated whether methanogens are sequestrated within rumen protozoa, and structural differences between rumen free-living methanogens and PAM. Rumen protozoa were harvested from totally faunated sheep, and six protozoal fractions (plus free-living microorganisms) were generated by sequential filtration. Holotrich-monofaunated sheep were also used to investigate the holotrich-associated methanogens. Protozoal size determined the number of PAM as big protozoa had 1.7–3.3 times more methanogen DNA than smaller protozoa, but also more endosymbiotic bacteria (2.2- to 3.5-fold times). Thus, similar abundance of methanogens with respect to total bacteria were observed across all protozoal fractions and free-living microorganisms, suggesting that methanogens are not accumulated within rumen protozoa in a greater proportion to that observed in the rumen as a whole. All rumen methanogen communities had similar diversity (22.2 ± 3.4 TRFs). Free-living methanogens composed a conserved community (67% similarity within treatment) in the rumen with similar diversity but different structures than PAM (P < 0.05). On the contrary, PAM constituted a more variable community (48% similarity), which differed between holotrich and total protozoa (P < 0.001). Thus, PAM constitutes a community, which requires further investigation as part of methane mitigation strategies. PMID:25195951

2006 Pathogen and Toxin Concentration Systems for Water Monitoring

DTIC Science & Technology

2012-07-24

design and construct a compact, portable automated device enabling the simultaneous concentration of protozoa , bacteria, bacterial spores, algae and...portable automated device enabling the simultaneous concentration of protozoa , bacteria, bacterial spores, algae and viruses from large volumes of various...construct a compact, portable automated device enabling the simultaneous concentration of protozoa , bacteria, bacterial spores, algae and viruses

Effect of nylon bag and protozoa on in vitro corn starch disappearance.

PubMed

van Zwieten, J T; van Vuuren, A M; Dijkstra, J

2008-03-01

An in vitro experiment was carried out to study whether the presence of protozoa in nylon bags can explain the underestimation of the in situ degradation of slowly degradable starch. Corn of a high (flint) and a low (dent) vitreousness variety was ground over a 3-mm screen, weighed in nylon bags with a pore size of 37 microm, and washed in cold water. Samples of washed cornstarch were incubated in 40-mL tubes with faunated and defaunated ruminal fluid. An additional amount of washed corn, in nylon bags, was inserted in each incubation tube. Incubations were carried out for 0, 2, 4, 6, 12, and 24 h, and starch residue in tube and nylon bag was determined. In general, starch disappearance from the nylon bag was less than from the tube, and was less with faunated than defaunated rumen fluid, but corn variety did not affect starch disappearance. When no protozoa were present, the disappearance of starch from the bags was higher after 6 and 12 h incubation compared with presence of protozoa. However, in the tubes, there was no difference in starch disappearance due to presence or absence of protozoa. Estimated lag time was higher in presence (4.6 h) then absence (3.6 h) of protozoa. It was concluded that the effect of presence or absence of protozoa on starch disappearance differs within or outside nylon bags. The reduced disappearance rate of starch inside the nylon bags in the presence of protozoa helps to explain the underestimation of starch degradation based on the in sacco procedure when compared with in vivo data upon incubation of slowly degradable starch sources.

Evaluation of the effects of albendazole and metronidazole on the ultrastructure of Giardia duodenalis, Trichomonas vaginalis and Spironucleus muris using transmission electron microscopy.

PubMed

Oxberry, M E; Thompson, R C; Reynoldson, J A

1994-08-01

The three closely related parasitic protozoa, Giardia duodenalis, Trichomonas vaginalis and Spironucleus muris, all have very different sensitivities to albendazole and metronidazole. Ultrastructural studies reveal that the cytoskeletal elements of the ventral disk in G. duodenalis are affected by albendazole, whereas the other two parasites, neither of which possess this structure, are not affected by albendazole to the same extent. This suggests that albendazole may be having its primary affect on G. duodenalis by binding to cytoskeletal proteins and ultimately causing death of the parasite. Death may be occurring as the parasite loses its ability to adhere to the intestinal villi and obtain nutrients. Metronidazole showed a different pattern of activity against the three parasites. The evidence obtained from these ultrastructural studies supports the current theory that metronidazole adversely affects protozoa by disrupting inner cell membranes.

[Malaria and intestinal protozoa].

PubMed

Rojo-Marcos, Gerardo; Cuadros-González, Juan

2016-03-01

Malaria is life threatening and requires urgent diagnosis and treatment. Incidence and mortality are being reduced in endemic areas. Clinical features are unspecific so in imported cases it is vital the history of staying in a malarious area. The first line treatments for Plasmodium falciparum are artemisinin combination therapies, chloroquine in most non-falciparum and intravenous artesunate if any severity criteria. Human infections with intestinal protozoa are distributed worldwide with a high global morbid-mortality. They cause diarrhea and sometimes invasive disease, although most are asymptomatic. In our environment populations at higher risk are children, including adopted abroad, immune-suppressed, travelers, immigrants, people in contact with animals or who engage in oral-anal sex. Diagnostic microscopic examination has low sensitivity improving with antigen detection or molecular methods. Antiparasitic resistances are emerging lately. Copyright © 2016 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Importance of airborne algae and protozoa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schlichting, H.E. Jr.

1969-12-01

Membrane filters, bubblers, and exposed culture media were used to sample viable algae and protozoa from the atmosphere in Michigan, Texas, and North Carolina from 1956 to 1967. Aerial algae and protozoa were most abundant and diverse in North Central Texas, 0-8 cells/ft/sup 3/, less abundant and diverse in Michigan, 0-1.8 cells/ft/sup 3/, and least abundant in Coastal North Carolina, less than 0.41 cells/ft/sup 3/. Other significant research from 1910 to 1968 is reviewed. A total of 187 taxa of algae and protozoa has been sampled and cultured through this period. The importance of airborne algae and protozoa to manmore » is shown as related to allergies, radioactivity, clogging of air filters, an aid in determining the origin of hurricanes and other storms and adding to the understanding of the dispersal of these microorganisms throughout the world. 15 references, 2 tables.« less

Protozoa and digestive tract parameters of the impala.

PubMed

Booyse, Dirk; Dehority, Burk A

2011-10-12

Intestinal contents were collected from eight impala at three different localities during the winter hunting season (2005-2009), as well as from another 24 animals from a one-year trial at a game farm called Ditholo (2003-2004). Gas production, protozoa counts and several other physiological parameters were measured from both rumen and caecum or colon contents. Only higher ophryoscolecid and Isotrichidae species of protozoa were counted and identified. Ostracodinium gracile was present in all 32 impala. Eudiplodinium maggii was present in 31 animals and Eudiplodinium impalae and Epidinium (either ecaudatum or caudatum) in 30 animals. Dasytricha ruminantium was present in only 11 of the impala. Concentrations of protozoa were correlated with the season of sample collection and highly correlated with the animals living on the game farm. Gas production (mL/g of wet rumen ingesta) was weakly correlated with protozoa concentration but not with the season of collection.

The aminoethylphosphonate-containing lipids of rumen protozoa

PubMed Central

Dawson, R. M. C.; Kemp, P.

1967-01-01

1. A method is presented for identifying and estimating the aminoethylphosphonate (ciliatine)-containing phospholipids in a complex mixture. 2. Evidence was obtained that the phospholipids of a pure culture of Entodinium caudatum and a mixed rumen protozoa sample contain diglyceride ciliatine, and a plasmalogen ciliatine was detected in the latter. 3. A ninhydrin-positive sphingolipid was isolated from rumen protozoa. Although chromatographically homogeneous on silica gel it contains two components, which were provisionally identified as ceramide ciliatine and ceramide phosphorylethanolamine. 4. A detailed phospholipid analysis of E. caudatum and rumen protozoa is presented. They contain no phosphatidylserine or cardiolipin, but an unidentified phosphoglyceride containing a zwitterionic amino acid is present. PMID:4967076

Genetically Engineered Yeast Expressing a Lytic Peptide from Bee Venom (Melittin) Kills Symbiotic Protozoa in the Gut of Formosan Subterranean Termites.

PubMed

Husseneder, Claudia; Donaldson, Jennifer R; Foil, Lane D

2016-01-01

The Formosan subterranean termite, Coptotermes formosanus Shiraki, is a costly invasive urban pest in warm and humid regions around the world. Feeding workers of the Formosan subterranean termite genetically engineered yeast strains that express synthetic protozoacidal lytic peptides has been shown to kill the cellulose digesting termite gut protozoa, which results in death of the termite colony. In this study, we tested if Melittin, a natural lytic peptide from bee venom, could be delivered into the termite gut via genetically engineered yeast and if the expressed Melittin killed termites via lysis of symbiotic protozoa in the gut of termite workers and/or destruction of the gut tissue itself. Melittin expressing yeast did kill protozoa in the termite gut within 56 days of exposure. The expressed Melittin weakened the gut but did not add a synergistic effect to the protozoacidal action by gut necrosis. While Melittin could be applied for termite control via killing the cellulose-digesting protozoa in the termite gut, it is unlikely to be useful as a standalone product to control insects that do not rely on symbiotic protozoa for survival.

Preliminary study on applicability of microsatellite DNA primers from parasite protozoa Trypanosoma cruzi in free-living protozoa

NASA Astrophysics Data System (ADS)

Zhang, Wenjing; Yu, Yuhe; Shen, Yunfen; Miao, Wei; Feng, Weisong

2004-04-01

In this paper, we took the lead in studying on specificity of the microsatellite DNA loci and applicability of microsatellite DNA primers in protozoa. In order to study characters of microsatellites in free-living protozoa, eight microsatellite loci primers developed from Trypanosoma cruzi (MCLE01, SCLE10, MCLE08, SCLE11, MCLF10, MCLG10, MCL03, MCL05) were employed to amplify microsatellite in four free-living protozoa, including Bodo designis, Euglena gracilis FACHB848, Paramecium bruzise and Tetrahymena thermophila BF1. In the amplification systems of P. bruzise, four loci (SCLE10, SCLE11, MCLF10, MCL03) were amplified successfully, and four amplification fragments were in proper size. In genome of E. gracilis FACHB848, five of eight primers brought five clear amplification bands. In B. designis, three (No.4, 5 and 7) of eight loci produced clear and sharp products without stutter bands, whereas no bands appeared in T. thermophila BF1. Further, eight 300 500 bp amplification fragments were cloned and sequenced. Nevertheless, all sequenced products did not contain corresponding microsatellite sequence, although Bodo is in the same order and has the nearest phylogenetic relation with Trypanosoma among these four species. Thus, the microsatellite DNA primers can not be applied among order or more far taxa, and the specificity of microsatellite DNA is very high in protozoa. The results of this study will contribute to our understanding of microsatellite DNA in protozoa.

Prevalence of intestinal protozoa infection among school-aged children on Pemba Island, Tanzania, and effect of single-dose albendazole, nitazoxanide and albendazole-nitazoxanide.

PubMed

Speich, Benjamin; Marti, Hanspeter; Ame, Shaali M; Ali, Said M; Bogoch, Isaac I; Utzinger, Jürg; Albonico, Marco; Keiser, Jennifer

2013-01-04

Pathogenic intestinal protozoa infections are common in school-aged children in the developing world and they are frequently associated with malabsorption syndromes and gastrointestinal morbidity. Since diagnosis of these parasites is difficult, prevalence data on intestinal protozoa is scarce. We collected two stool samples from school-aged children on Pemba Island, Tanzania, as part of a randomized controlled trial before and 3 weeks after treatment with (i) single-dose albendazole (400 mg); (ii) single-dose nitazoxanide (1,000 mg); (iii) nitazoxanide-albendazole combination (1,000 mg-400 mg), with each drug given separately on two consecutive days; and (iv) placebo. Formalin-fixed stool samples were examined for the presence of intestinal protozoa using an ether-concentration method to determine the prevalence and estimate cure rates (CRs). Almost half (48.7%) of the children were diagnosed with at least one of the (potentially) pathogenic protozoa Giardia intestinalis, Entamoeba histolytica/E. dispar and Blastocystis hominis. Observed CRs were high for all treatment arms, including placebo. Nitazoxanide showed a significant effect compared to placebo against the non-pathogenic protozoon Entamoeba coli. Intestinal protozoa infections might be of substantial health relevance even in settings where they are not considered as a health problem. Examination of a single stool sample with the ether-concentration method lacks sensitivity for the diagnosis of intestinal protozoa, and hence, care is indicated when interpreting prevalence estimates and treatment effects.

Prevalence of intestinal protozoa infection among school-aged children on Pemba Island, Tanzania, and effect of single-dose albendazole, nitazoxanide and albendazole-nitazoxanide

PubMed Central

2013-01-01

Background Pathogenic intestinal protozoa infections are common in school-aged children in the developing world and they are frequently associated with malabsorption syndromes and gastrointestinal morbidity. Since diagnosis of these parasites is difficult, prevalence data on intestinal protozoa is scarce. Methods We collected two stool samples from school-aged children on Pemba Island, Tanzania, as part of a randomized controlled trial before and 3 weeks after treatment with (i) single-dose albendazole (400 mg); (ii) single-dose nitazoxanide (1,000 mg); (iii) nitazoxanide-albendazole combination (1,000 mg–400 mg), with each drug given separately on two consecutive days; and (iv) placebo. Formalin-fixed stool samples were examined for the presence of intestinal protozoa using an ether-concentration method to determine the prevalence and estimate cure rates (CRs). Results Almost half (48.7%) of the children were diagnosed with at least one of the (potentially) pathogenic protozoa Giardia intestinalis, Entamoeba histolytica/E. dispar and Blastocystis hominis. Observed CRs were high for all treatment arms, including placebo. Nitazoxanide showed a significant effect compared to placebo against the non-pathogenic protozoon Entamoeba coli. Conclusions Intestinal protozoa infections might be of substantial health relevance even in settings where they are not considered as a health problem. Examination of a single stool sample with the ether-concentration method lacks sensitivity for the diagnosis of intestinal protozoa, and hence, care is indicated when interpreting prevalence estimates and treatment effects. PMID:23289920

Molecular characterization of Clostridium perfringens strains isolated from diseased turkeys in Italy.

PubMed

Giovanardi, Davide; Drigo, Ilenia; De Vidi, Beatrice; Agnoletti, Fabrizio; Viel, Laura; Capello, Katia; Berto, Giacomo; Bano, Luca

2016-06-01

One hundred and six Clostridium perfringens field strains, isolated from diseased turkeys in Italy between 2006 and 2015, were toxinotyped by polymerase chain reaction. Strains were derived from intestines (87), livers (17) and subcutaneous tissues (2). In addition to the four major toxins, strains were also screened for NetB toxin, enterotoxin and beta2 toxin encoding genes. The intestinal gross lesions of turkeys with enteric disorders were statistically studied with respect to the presence of C. perfringens beta2 toxin encoding gene and coccidia in the gut. All the isolates belonged to the toxinotype A and were netB negative. Enterotoxin (cpe) and beta2 toxin (cpb2) encoding genes were detected in two (2.63%) and 76 (71.69%) strains, respectively. Toxinotype results agree with the few published reports concerning the genetic characterization of C. perfringens of turkey origin. On the contrary, the presence of netB and cpb2 genes differs from the results of a previous study where these genes were detected respectively in 6.6% and in 0.5% of the tested strains. Necrotic enteritis in turkeys was not statistically correlated either to the presence of cpb2 gene, or to the synergistic effect operated by coccidia, even though a high percentage of birds with these protozoa in the gut showed necrotic enteritis lesions (64.29%).

Household sanitation is associated with lower risk of bacterial and protozoal enteric infections, but not viral infections and diarrhoea, in a cohort study in a low-income urban neighbourhood in Vellore, India.

PubMed

Berendes, David; Leon, Juan; Kirby, Amy; Clennon, Julie; Raj, Suraja; Yakubu, Habib; Robb, Katharine; Kartikeyan, Arun; Hemavathy, Priya; Gunasekaran, Annai; Roy, Sheela; Ghale, Ben Chirag; Kumar, J Senthil; Mohan, Venkata Raghava; Kang, Gagandeep; Moe, Christine

2017-09-01

This study examined associations between household sanitation and enteric infection - including diarrhoeal-specific outcomes - in children 0-2 years of age in a low-income, dense urban neighbourhood. As part of the MAL-ED study, 230 children in a low-income, urban, Indian neighbourhood provided stool specimens at 14-17 scheduled time points and during diarrhoeal episodes in the first 2 years of life that were analysed for bacterial, parasitic (protozoa and helminths) and viral pathogens. From interviews with caregivers in 100 households, the relationship between the presence (and discharge) of household sanitation facilities and any, pathogen-specific, and diarrhoea-specific enteric infection was tested through mixed-effects Poisson regression models. Few study households (33%) reported having toilets, most of which (82%) discharged into open drains. Controlling for season and household socio-economic status, the presence of a household toilet was associated with lower risks of enteric infection (RR: 0.91, 95% CI: 0.79-1.06), bacterial infection (RR: 0.87, 95% CI: 0.75-1.02) and protozoal infection (RR: 0.64, 95% CI: 0.39-1.04), although not statistically significant, but had no association with diarrhoea (RR: 1.00, 95% CI: 0.68-1.45) or viral infections (RR: 1.12, 95% CI: 0.79-1.60). Models also suggested that the relationship between household toilets discharging to drains and enteric infection risk may vary by season. The presence of a household toilet was associated with lower risk of bacterial and protozoal enteric infections, but not diarrhoea or viral infections, suggesting the health effects of sanitation may be more accurately estimated using outcome measures that account for aetiologic agents. © 2017 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Rumen Protozoal Degradation of Structurally Intact Forage Tissues

PubMed Central

Amos, Henry E.; Akin, Danny E.

1978-01-01

The association with and digestion of intact leaf sections of cool- and warm-season grasses by cattle rumen protozoa were investigated by light and scanning electron microscopy and by in vitro dry matter disappearance studies. Within extensively degraded areas of mesophyll tissue in cool-season forages, almost all protozoa were Epidinium ecaudatum form caudatum, with maximum numbers at 4 to 10 h of incubation. However, few protozoa were found inside warm-season forage leaves. In in vitro dry matter disappearance studies of a series of incubations with and without 1.6 mg of streptomycin per ml, which inhibited the cellulolytic activity of the bacteria, and in comparison with uninoculated controls, rumen protozoa degraded 11.0 and 3.7 percentage units of orchardgrass and bermuda-grass, respectively. Scanning electron microscopy showed that the tissues degraded in orchardgrass consisted of large amounts of mesophyll and portions of the parenchyma bundle sheath and epidermis; no tissue loss due to the protozoa was observed in bermudagrass. The relationship of these observations to forage digestion is discussed. Images PMID:16345315

Multiplex PCR detection of waterborne intestinal protozoa: microsporidia, Cyclospora, and Cryptosporidium.

PubMed

Lee, Seung-Hyun; Joung, Migyo; Yoon, Sejoung; Choi, Kyoungjin; Park, Woo-Yoon; Yu, Jae-Ran

2010-12-01

Recently, emerging waterborne protozoa, such as microsporidia, Cyclospora, and Cryptosporidium, have become a challenge to human health worldwide. Rapid, simple, and economical detection methods for these major waterborne protozoa in environmental and clinical samples are necessary to control infection and improve public health. In the present study, we developed a multiplex PCR test that is able to detect all these 3 major waterborne protozoa at the same time. Detection limits of the multiplex PCR method ranged from 10(1) to 10(2) oocysts or spores. The primers for microsporidia or Cryptosporidium used in this study can detect both Enterocytozoon bieneusi and Encephalitozoon intestinalis, or both Cryptosporidium hominis and Cryptosporidium parvum, respectively. Restriction enzyme digestion of PCR products with BsaBI or BsiEI makes it possible to distinguish the 2 species of microsporidia or Cryptosporidium, respectively. This simple, rapid, and cost-effective multiplex PCR method will be useful for detecting outbreaks or sporadic cases of waterborne protozoa infections.

Nutritional quality of fish faeces is enhanced by highly unsaturated fatty acid-producing heterotrophic protozoa

NASA Astrophysics Data System (ADS)

Fujibayashi, Megumu; Tanaka, Nobuyuki; Hashido, Shun; Takasawa, Aya; Nishimura, Osamu

2018-05-01

Highly unsaturated fatty acids such as 20:5n3 (EPA) are both hormone precursors and cell membrane components, making them important nutrients for aquatic animals. Many animals must obtain EPA from their diets because they cannot synthesize enough EPA to meet their requirements, and algae are the main source of EPA in aquatic ecosystems. In a previous study, we detected EPA in the faeces of Danio rerio, a freshwater fish, even though the fish consumed a green algae diet that did not contain EPA. The objective of this study was to determine why EPA was detected in fish faeces. A significant positive relationship was detected between the number of heterotrophic protozoa and the concentration of EPA in the faeces, which suggests that this EPA was of protozoan origin. In addition, another experiment showed that protozoa adhered to faeces far more than the green algal diet remnants, which indicates that protozoa preferred to swarm on faeces. Furthermore, we cultured protozoa in an EPA-free medium and fed them a bacterial diet also lacking EPA, and found that Cyclidium sp. synthesized EPA de novo. The results demonstrate that protozoa produce essential fatty acids and enhance the nutritional quality of animal faeces in detritus-based food webs in freshwater ecosystems.

Comparison digestibility and protozoa population of Khuzestan water buffalo and Holstein cow.

PubMed

Jabari, Safora; Eslami, Moosa; Chaji, Morteza; Mohammadabadi, Tahereh; Bojarpour, Mohammad

2014-01-01

The major aim of this study was to compare the morphology and activity of rumen protozoa of Khuzestan water buffalo and Holstein cow using in vitro digestibility and gas production parameters of steam treated sugarcane pith. Rumen fluid obtained from two buffalo and cow steers fed the same diet, 30:70 concentrate: forage. To separate rumen protozoa, antibiotic solution and fungicides were added to rumen fluid. The results of present experiment indicated that the neutral detergent fiber (NDF; 7.8 vs. 1.69%) and acid detergent fiber (ADF; 6.24 vs. 3.24%) digestibility of steam treated sugarcane pith by rumen protozoal population of Khuzestan buffalo was higher than those of cow (p < 0.05). Also, digestibility of dry matter, NDF and ADF by whole buffalo micro-organisms was more than those in cow (p < 0.05). The results indicated that the potential of gas production of sugarcane pith by rumen protozoa in water buffalo was more than that of cow (p < 0.05). Total rumen ciliate protozoa numbers in water buffalo were significantly higher than those of cow (3.68 × 10(5) vs. 2.18 × 10(5) mL(-1) of rumen content) (p < 0.05). The number of Diplodinium in buffalo was more than that of cow (41.27 vs. 35.7% of total rumen protozoa, respectively). Percentage of Entodinium, Epidinium, Ophryoscolex and Isotricha in cow was more than those of buffalo. Therefore, in the same diet, protozoa and total rumen micro-organisms of Khuzestan water buffalo have higher digestion activity compared to Holstein cow.

Mobility of Protozoa through Narrow Channels

PubMed Central

Wang, Wei; Shor, Leslie M.; LeBoeuf, Eugene J.; Wikswo, John P.; Kosson, David S.

2005-01-01

Microbes in the environment are profoundly affected by chemical and physical heterogeneities occurring on a spatial scale of millimeters to micrometers. Physical refuges are critical for maintaining stable bacterial populations in the presence of high predation pressure by protozoa. The effects of microscale heterogeneity, however, are difficult to replicate and observe using conventional experimental techniques. The objective of this research was to investigate the effect of spatial constraints on the mobility of six species of marine protozoa. Microfluidic devices were created with small channels similar in size to pore spaces in soil or sediment systems. Individuals from each species of protozoa tested were able to rapidly discover and move within these channels. The time required for locating the channel entrance from the source well increased with protozoan size and decreased with channel height. Protozoa of every species were able to pass constrictions with dimensions equal to or smaller than the individual's unconstrained cross-sectional area. Channel geometry was also an important factor affecting protozoan mobility. Linear rates of motion for various species of protozoa varied by channel size. In relatively wide channels, typical rates of motion were 300 to 500 μm s−1 (or about 1 m per hour). As the channel dimensions decreased, however, motilities slowed more than an order of magnitude to 20 μm s−1. Protozoa were consistently observed to exhibit several strategies for successfully traversing channel reductions. The empirical results and qualitative observations resulting from this research help define the physical limitations on protozoan grazing, a critical process affecting microbes in the environment. PMID:16085857

Regional Disease Vector Ecology Profile East Asia

DTIC Science & Technology

2002-04-01

hepatitis A and E, rotaviruses, and other viral species. Infection with pathogenic protozoa, such as Entamoeba histolytica, Giardia lamblia and...to secretions or blood from infected animals or humans. Medical workers treating patients are at high risk of becoming infected . Clinical symptoms...caused by any of 4 protozoan species in the genus Plasmodium that are transmitted by the bite of an infective female Anopheles mosquito. Clinical symptoms

9 CFR 121.1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., fungi, rickettsiae, or protozoa), or infectious substance, or any naturally occurring, bioengineered, or... (including, but not limited to, bacteria, viruses, fungi, rickettsiae, or protozoa), or infectious substances...

7 CFR 331.1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... microorganism (including, but not limited to, bacteria, viruses, fungi, rickettsiae, or protozoa), or infectious..., fungi, rickettsiae, or protozoa), or infectious substances, or a recombinant or synthesized molecule...

9 CFR 121.1 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

..., fungi, rickettsiae, or protozoa), or infectious substance, or any naturally occurring, bioengineered, or... (including, but not limited to, bacteria, viruses, fungi, rickettsiae, or protozoa), or infectious substances...

9 CFR 121.1 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

..., fungi, rickettsiae, or protozoa), or infectious substance, or any naturally occurring, bioengineered, or... (including, but not limited to, bacteria, viruses, fungi, rickettsiae, or protozoa), or infectious substances...

Three-dimensional structures in the design of therapeutics targeting parasitic protozoa: reflections on the past, present and future.

PubMed

Hol, Wim G J

2015-05-01

Parasitic protozoa cause a range of diseases which threaten billions of human beings. They are responsible for tremendous mortality and morbidity in the least-developed areas of the world. Presented here is an overview of the evolution over the last three to four decades of structure-guided design of inhibitors, leads and drug candidates aiming at targets from parasitic protozoa. Target selection is a crucial and multi-faceted aspect of structure-guided drug design. The major impact of advances in molecular biology, genome sequencing and high-throughput screening is touched upon. The most advanced crystallographic techniques, including XFEL, have already been applied to structure determinations of drug targets from parasitic protozoa. Even cryo-electron microscopy is contributing to our understanding of the mode of binding of inhibitors to parasite ribosomes. A number of projects have been selected to illustrate how structural information has assisted in arriving at promising compounds that are currently being evaluated by pharmacological, pharmacodynamic and safety tests to assess their suitability as pharmaceutical agents. Structure-guided approaches are also applied to incorporate properties into compounds such that they are less likely to become the victim of resistance mechanisms. A great increase in the number of novel antiparasitic compounds will be needed in the future. These should then be combined into various multi-compound therapeutics to circumvent the diverse resistance mechanisms that render single-compound, or even multi-compound, drugs ineffective. The future should also see (i) an increase in the number of projects with a tight integration of structural biology, medicinal chemistry, parasitology and pharmaceutical sciences; (ii) the education of more `medicinal structural biologists' who are familiar with the properties that compounds need to have for a high probability of success in the later steps of the drug-development process; and (iii) the expansion of drug-development capabilities in middle- and low-income countries.

Foodborne protozoan parasites.

PubMed

Dawson, David

2005-08-25

This report addresses Cryptosporidium, Giardia, Cyclospora, and more briefly, Toxoplasma as the main parasitic protozoa of concern to food production worldwide. Other parasitic protozoa may be spread in food or water but are not considered as great a risk to food manufacture. The protozoan parasites Cryptosporidium, Giardia, and Cyclospora have proven potential to cause waterborne and foodborne disease. Toxoplasma gondii has been considered a risk in specific cases, but humans are not its primary host. Cryptosporidium and Giardia are widespread in the environment, particularly the aquatic environment, and major outbreaks of cryptosporidiosis and giardiasis have occurred as a result of contaminated drinking water. Large outbreaks of waterborne cyclosporiasis have not been identified. Cryptosporidium, Giardia, and Cyclospora have potential significance in the preparation and consumption of fresh produce and in catering practice, in which ready-to-eat foods may be served that have not received heat treatment. None of the three organisms Cryptosporidium, Giardia, and Cyclospora has been shown to be a problem for heat processed food or tap water that has undergone appropriate treatment at a water treatment works. All three are sensitive to standard pasteurisation techniques. Although humans are not a primary host for T. gondii, the potential exists for both waterborne and foodborne toxoplasmosis. Parasitic protozoa do not multiply in foods, but they may survive in or on moist foods for months in cool, damp environments. Their ecology makes control of these parasites difficult. For general control of parasitic protozoa in the food chain, the following steps are necessary: - Follow good hygienic practice in food service and catering industries.- Minimise dissemination of cysts and oocysts in the farming environment and via human waste management.- Include these microorganisms in Hazard Analysis Critical Control Point (HACCP) plans of water suppliers, industries or sectors that use fresh produce, and operations in which contaminated process or ingredient water could end up in the product (e.g., where water supplies may become contaminated).

Three-dimensional structures in the design of therapeutics targeting parasitic protozoa: reflections on the past, present and future

PubMed Central

Hol, Wim G. J.

2015-01-01

Parasitic protozoa cause a range of diseases which threaten billions of human beings. They are responsible for tremendous mortality and morbidity in the least-developed areas of the world. Presented here is an overview of the evolution over the last three to four decades of structure-guided design of inhibitors, leads and drug candidates aiming at targets from parasitic protozoa. Target selection is a crucial and multi-faceted aspect of structure-guided drug design. The major impact of advances in molecular biology, genome sequencing and high-throughput screening is touched upon. The most advanced crystallographic techniques, including XFEL, have already been applied to structure determinations of drug targets from parasitic protozoa. Even cryo-electron microscopy is contributing to our understanding of the mode of binding of inhibitors to parasite ribosomes. A number of projects have been selected to illustrate how structural information has assisted in arriving at promising compounds that are currently being evaluated by pharmacological, pharmacodynamic and safety tests to assess their suitability as pharmaceutical agents. Structure-guided approaches are also applied to incorporate properties into compounds such that they are less likely to become the victim of resistance mechanisms. A great increase in the number of novel antiparasitic compounds will be needed in the future. These should then be combined into various multi-compound therapeutics to circumvent the diverse resistance mechanisms that render single-compound, or even multi-compound, drugs ineffective. The future should also see (i) an increase in the number of projects with a tight integration of structural biology, medicinal chemistry, parasitology and pharmaceutical sciences; (ii) the education of more ‘medicinal structural biologists’ who are familiar with the properties that compounds need to have for a high probability of success in the later steps of the drug-development process; and (iii) the expansion of drug-development capabilities in middle- and low-income countries. PMID:25945701

Gut Protozoa: Friends or Foes of the Human Gut Microbiota?

PubMed

Chabé, Magali; Lokmer, Ana; Ségurel, Laure

2017-12-01

The importance of the gut microbiota for human health has sparked a strong interest in the study of the factors that shape its composition and diversity. Despite the growing evidence suggesting that helminths and protozoa significantly interact with gut bacteria, gut microbiome studies remain mostly focused on prokaryotes and on populations living in industrialized countries that typically have a low parasite burden. We argue that protozoa, like helminths, represent an important factor to take into account when studying the gut microbiome, and that their presence - especially considering their long coevolutionary history with humans - may be beneficial. From this perspective, we examine the relationship between the protozoa and their hosts, as well as their relevance for public health. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cloning and bacterial expression of adenosine-5'-triphosphate sulfurylase from the enteric protozoan parasite Entamoeba histolytica.

PubMed

Nozaki, T; Arase, T; Shigeta, Y; Asai, T; Leustek, T; Takeuchi, T

1998-12-08

A gene encoding adenosine-5'-triphosphate sulfurylase (AS) was cloned from the enteric protozoan parasite Entamoeba histolytica by polymerase chain reaction using degenerate oligonucleotide primers corresponding to conserved regions of the protein from a variety of organisms. The deduced amino acid sequence of E. histolytica AS revealed a calculated molecular mass of 47925 Da and an unusual basic pI of 9.38. The amebic protein sequence showed 23-48% identities with AS from bacteria, yeasts, fungi, plants, and animals with the highest identities being to Synechocystis sp. and Bacillus subtilis (48 and 44%, respectively). Four conserved blocks including putative sulfate-binding and phosphate-binding regions were highly conserved in the E. histolytica AS. The upstream region of the AS gene contained three conserved elements reported for other E. histolytica genes. A recombinant E. histolytica AS revealed enzymatic activity, measured in both the forward and reverse directions. Expression of the E. histolytica AS complemented cysteine auxotrophy of the AS-deficient Escherichia coli strains. Genomic hybridization revealed that the AS gene exists as a single copy gene. In the literature, this is the first description of an AS gene in Protozoa.

21 CFR 558.115 - Carbadox.

Code of Federal Regulations, 2011 CFR

2011-04-01

... bacterial swine enteritis (salmonellosis or necrotic enteritis caused by Salmonella choleraesuis); increased... dysentery); control of bacterial swine enteritis (salmonellosis or necrotic enteritis caused by Salmonella...

Study of the effect of presence or absence of protozoa on rumen fermentation and microbial protein contribution to the chyme.

PubMed

Belanche, A; Abecia, L; Holtrop, G; Guada, J A; Castrillo, C; de la Fuente, G; Balcells, J

2011-12-01

The aim of this study was to investigate the effect of presence or absence of protozoa on rumen fermentation and efficiency of microbial protein synthesis under different diets. Of 20 twin paired lambs, 1 lamb of each pair was isolated from the ewe within 24 h after birth and reared in a protozoa-free environment (n = 10), whereas their respective twin-siblings remained with the ewe (faunated, n = 10). When lambs reached 6 mo of age, 5 animals of each group were randomly allocated to 1 of 2 experimental diets consisting of either alfalfa hay as the sole diet, or 50:50 mixed with ground barley grain according to a 2 × 2 factorial arrangement of treatments. After 15 d of adaptation to the diet, the animals were euthanized and total rumen and abomasal contents were sampled to estimate rumen microbial synthesis using C(31) alkane as flow marker. Different ((15)N and purine bases) and a novel (recombinant DNA sequences) microbial markers, combined with several microbial reference extracts (rumen protozoa, liquid and solid associated bacteria) were evaluated. Absence of rumen protozoa modified the rumen fermentation pattern and decreased total tract OM and NDF digestibility in 2.0 and 5.1 percentage points, respectively. The effect of defaunation on microbial N flow was weak, however, and was dependent on the microbial marker and microbial reference extract considered. Faunated lambs fed with mixed diet showed the greatest rumen protozoal concentration and the least efficient microbial protein synthesis (29% less than the other treatments), whereas protozoa-free lambs fed with mixed diet presented the smallest ammonia concentration and 34% greater efficiency of N utilization than the other treatments. Although (15)N gave the most precise estimates of microbial synthesis, the use of recombinant DNA sequences represents an alternative that allows separate quantification of the bacteria and protozoa contributions. This marker showed that presence of protozoa decrease the bacterial-N flow through the abomasum by 33%, whereas the protozoa-N contribution to the microbial N flow increased from 1.9 to 14.1% when barley grain was added to the alfalfa hay. Absolute data related to intestinal flow must be treated with caution because the limitations of the sampling and maker system employed.

21 CFR 558.311 - Lasalocid.

Code of Federal Regulations, 2011 CFR

2011-04-01

... of bacterial enteritis caused by E. coli and bacterial pneumonia caused by P. multocida organisms... improved feed efficiency; and for treatment of bacterial enteritis caused by E. coli and bacterial... treatment of bacterial enteritis caused by E. coli and bacterial pneumonia caused by P. multocida organisms...

Amino acid composition of rumen bacteria and protozoa in cattle.

PubMed

Sok, M; Ouellet, D R; Firkins, J L; Pellerin, D; Lapierre, H

2017-07-01

Because microbial crude protein (MCP) constitutes more than 50% of the protein digested in cattle, its AA composition is needed to adequately estimate AA supply. Our objective was to update the AA contributions of the rumen microbial AA flowing to the duodenum using only studies from cattle, differentiating between fluid-associated bacteria (FAB), particle-associated bacteria (PAB), and protozoa, based on published literature (53, 16, and 18 treatment means were used for each type of microorganism, respectively). In addition, Cys and Met reported concentrations were retained only when an adequate protection of the sulfur groups was performed before the acid hydrolysis. The total AA (or true protein) fraction represented 82.4% of CP in bacteria. For 10 AA, including 4 essential AA, the AA composition differed between protozoa and bacteria. The most noticeable differences were a 45% lower Lys concentration and 40% higher Ala concentration in bacteria than in protozoa. Differences between FAB and PAB were less pronounced than differences between bacteria and protozoa. Assuming 33% FAB, 50% PAB, and 17% of protozoa in MCP duodenal flow, the updated concentrations of AA would decrease supply estimates of Met, Thr, and Val originating from MCP and increase those of Lys and Phe by 5 to 10% compared with those calculated using the FAB composition reported previously. Therefore, inclusion of the contribution of PAB and protozoa to the duodenal MCP flow is needed to adequately estimate AA supply from microbial origin when a factorial method is used to estimate duodenal AA flow. Furthermore, acknowledging the fact that hydrolysis of 1 kg of true microbial protein yields 1.16 kg of free AA substantially increases the estimates of AA supply from MCP. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of progressive inoculation of fauna-free sheep with holotrich protozoa and total-fauna on rumen fermentation, microbial diversity and methane emissions

PubMed Central

Belanche, Alejandro; de la Fuente, Gabriel; Newbold, Charles J.

2014-01-01

Rumen methanogenesis represents an energy waste for the ruminant and an important source of greenhouse gas; thus, integrated studies are needed to fully understand this process. Eight fauna-free sheep were used to investigate the effect of successive inoculation with holotrich protozoa then with total fauna on rumen methanogenesis. Holotrichs inoculation neither altered rumen fermentation rate nor diet digestibility, but increased concentrations of acetate (+15%), butyrate (+57%), anaerobic fungi (+0.82 log), methanogens (+0.41 log) and methanogenesis (+54%). Further inoculation with total fauna increased rumen concentrations of protozoa (+1.0 log), bacteria (+0.29 log), anaerobic fungi (+0.78 log), VFA (+8%), ammonia and fibre digestibility (+17%) without affecting levels of methanogens or methanogenesis. Rumen methanogens population was fairly stable in terms of structure and diversity, while the bacterial community was highly affected by the treatments. Inoculation with holotrich protozoa increased bacterial diversity. Further inoculation with total fauna lowered bacterial diversity but increased concentrations of certain propionate and lactate-producing bacteria, suggesting that alternative H2 sinks could be relevant. This experiment suggests that holotrich protozoa have a greater impact on rumen methanogenesis than entodiniomorphids. Thus, further research is warranted to understand the effect of holotrich protozoa on methane formation and evaluate their elimination from the rumen as a potential methane mitigation strategy. PMID:25764558

Effect of progressive inoculation of fauna-free sheep with holotrich protozoa and total-fauna on rumen fermentation, microbial diversity and methane emissions.

PubMed

Belanche, Alejandro; de la Fuente, Gabriel; Newbold, Charles J

2015-03-01

Rumen methanogenesis represents an energy waste for the ruminant and an important source of greenhouse gas; thus, integrated studies are needed to fully understand this process. Eight fauna-free sheep were used to investigate the effect of successive inoculation with holotrich protozoa then with total fauna on rumen methanogenesis. Holotrichs inoculation neither altered rumen fermentation rate nor diet digestibility, but increased concentrations of acetate (+15%), butyrate (+57%), anaerobic fungi (+0.82 log), methanogens (+0.41 log) and methanogenesis (+54%). Further inoculation with total fauna increased rumen concentrations of protozoa (+1.0 log), bacteria (+0.29 log), anaerobic fungi (+0.78 log), VFA (+8%), ammonia and fibre digestibility (+17%) without affecting levels of methanogens or methanogenesis. Rumen methanogens population was fairly stable in terms of structure and diversity, while the bacterial community was highly affected by the treatments. Inoculation with holotrich protozoa increased bacterial diversity. Further inoculation with total fauna lowered bacterial diversity but increased concentrations of certain propionate and lactate-producing bacteria, suggesting that alternative H2 sinks could be relevant. This experiment suggests that holotrich protozoa have a greater impact on rumen methanogenesis than entodiniomorphids. Thus, further research is warranted to understand the effect of holotrich protozoa on methane formation and evaluate their elimination from the rumen as a potential methane mitigation strategy. © Federation of European Microbiological Society 2014.

Protozoa inhibition by different salts: Osmotic stress or ionic stress?

PubMed

Li, Changhao; Li, Jingya; Lan, Christopher Q; Liao, Dankui

2017-09-01

Cell density and morphology changes were tested to examine the effects of salts including NaHCO 3 , NaCl, KHCO 3 , and KCl at 160 mM on protozoa. It was demonstrated that ionic stress rather than osmotic stress led to protozoa cell death and NaHCO 3 was shown to be the most effective inhibitor. Deformation of cells and cell shrinkage were observed when protozoan cells were exposed to polyethylene glycol (PEG) or any of the salts. However, while PEG treated cells could fully recover in both number and size, only a small portion of the salt-treated cells survive and cell size was 36-58% smaller than the regular. The disappearance of salt-treated protozoa cells was hypothetically attributed to disruption of the cytoplasmic membrane of these cells. It is further hypothesized that the PEG-treated protozoan cells carried out regulatory volume increase (RVI) after the osmotic shock but the RVI of salt-treated protozoa was hurdled to varied extents. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1418-1424, 2017. © 2017 American Institute of Chemical Engineers.

How Trypanosoma cruzi handles cell cycle arrest promoted by camptothecin, a topoisomerase I inhibitor.

PubMed

Zuma, Aline Araujo; Mendes, Isabela Cecília; Reignault, Lissa Catherine; Elias, Maria Carolina; de Souza, Wanderley; Machado, Carlos Renato; Motta, Maria Cristina M

2014-02-01

The protozoan Trypanosoma cruzi is the etiological agent of Chagas disease, which affects approximately 8 million people in Latin America. This parasite contains a single nucleus and a kinetoplast, which harbors the mitochondrial DNA (kDNA). DNA topoisomerases act during replication, transcription and repair and modulate DNA topology by reverting supercoiling in the DNA double-strand. In this work, we evaluated the effects promoted by camptothecin, a topoisomerase I inhibitor that promotes protozoan proliferation impairment, cell cycle arrest, ultrastructure alterations and DNA lesions in epimastigotes of T. cruzi. The results showed that inhibition of cell proliferation was reversible only at the lowest drug concentration (1μM) used. The unpacking of nuclear heterochromatin and mitochondrion swelling were the main ultrastructural modifications observed. Inhibition of parasite proliferation also led to cell cycle arrest, which was most likely caused by nuclear DNA lesions. Following camptothecin treatment, some of the cells restored their DNA, whereas others entered early apoptosis but did not progress to late apoptosis, indicating that the protozoa stay alive in a "senescence-like" state. This programmed cell death may be associated with a decrease in mitochondrial membrane potential and an increase in the production of reactive oxygen species. Taken together, these results indicate that the inhibition of T. cruzi proliferation is related to events capable of affecting cell cycle, DNA organization and mitochondrial activity. Copyright © 2014. Published by Elsevier B.V.

New advances in molecular epizootiology of canine hematic protozoa from Venezuela, Thailand and Spain.

PubMed

Criado-Fornelio, A; Rey-Valeiron, C; Buling, A; Barba-Carretero, J C; Jefferies, R; Irwin, P

2007-03-31

The prevalence of hematozoan infections (Hepatozoon canis and Babesia sp., particularly Babesia canis vogeli) in canids from Venezuela, Thailand and Spain was studied by amplification and sequencing of the 18S rRNA gene. H. canis infections caused simultaneously by two different isolates were confirmed by RFLP analysis in samples from all the geographic regions studied. In Venezuela, blood samples from 134 dogs were surveyed. Babesia infections were found in 2.24% of the dogs. Comparison of sequences of the 18S rRNA gene indicated that protozoan isolates were genetically identical to B. canis vogeli from Japan and Brazil. H. canis infected 44.77 per cent of the dogs. A representative sample of Venezuelan H. canis isolates (21.6% of PCR-positives) was sequenced. Many of them showed 18S rRNA gene sequences identical to H. canis Spain 2, albeit two less frequent genotypes were found in the sample studied. In Thailand, 20 dogs were analyzed. No infections caused by Babesia were diagnosed, whereas 30 per cent of the dogs were positive to hematozoan infection. Two protozoa isolates showing 99.7-100% identity to H. canis Spain 2 were found. In Spain, 250 dogs were studied. B. canis vogeli infected 0.01% of the animals. The sequence of the 18S rRNA gene in Spanish isolates of this protozoa was closely related to those previously deposited in GenBank (> 99% identity). Finally, 20 red foxes were screened for hematozoans employing semi-nested PCR and primers designed to detect Babesia/Theileria. Fifty percent of the foxes were positive to Theileria annae. In addition, it was found that the PCR assay was able as well to detect Hepatozoon infections. Thirty five percent of the foxes were infected with two different H. canis isolates showing 99.8-100% identity to Curupira 1 from Brazil.

Sterol Biosynthesis Is Required for Heat Resistance but Not Extracellular Survival in Leishmania

PubMed Central

Xu, Wei; Hsu, Fong-Fu; Baykal, Eda; Huang, Juyang; Zhang, Kai

2014-01-01

Sterol biosynthesis is a crucial pathway in eukaryotes leading to the production of cholesterol in animals and various C24-alkyl sterols (ergostane-based sterols) in fungi, plants, and trypanosomatid protozoa. Sterols are important membrane components and precursors for the synthesis of powerful bioactive molecules, including steroid hormones in mammals. Their functions in pathogenic protozoa are not well characterized, which limits the development of sterol synthesis inhibitors as drugs. Here we investigated the role of sterol C14α-demethylase (C14DM) in Leishmania parasites. C14DM is a cytochrome P450 enzyme and the primary target of azole drugs. In Leishmania, genetic or chemical inactivation of C14DM led to a complete loss of ergostane-based sterols and accumulation of 14-methylated sterols. Despite the drastic change in lipid composition, C14DM-null mutants (c14dm −) were surprisingly viable and replicative in culture. They did exhibit remarkable defects including increased membrane fluidity, failure to maintain detergent resistant membrane fraction, and hypersensitivity to heat stress. These c14dm − mutants showed severely reduced virulence in mice but were highly resistant to itraconazole and amphotericin B, two drugs targeting sterol synthesis. Our findings suggest that the accumulation of toxic sterol intermediates in c14dm − causes strong membrane perturbation and significant vulnerability to stress. The new knowledge may help improve the efficacy of current drugs against pathogenic protozoa by exploiting the fitness loss associated with drug resistance. PMID:25340392

Sterol biosynthesis is required for heat resistance but not extracellular survival in leishmania.

PubMed

Xu, Wei; Hsu, Fong-Fu; Baykal, Eda; Huang, Juyang; Zhang, Kai

2014-10-01

Sterol biosynthesis is a crucial pathway in eukaryotes leading to the production of cholesterol in animals and various C24-alkyl sterols (ergostane-based sterols) in fungi, plants, and trypanosomatid protozoa. Sterols are important membrane components and precursors for the synthesis of powerful bioactive molecules, including steroid hormones in mammals. Their functions in pathogenic protozoa are not well characterized, which limits the development of sterol synthesis inhibitors as drugs. Here we investigated the role of sterol C14α-demethylase (C14DM) in Leishmania parasites. C14DM is a cytochrome P450 enzyme and the primary target of azole drugs. In Leishmania, genetic or chemical inactivation of C14DM led to a complete loss of ergostane-based sterols and accumulation of 14-methylated sterols. Despite the drastic change in lipid composition, C14DM-null mutants (c14dm(-)) were surprisingly viable and replicative in culture. They did exhibit remarkable defects including increased membrane fluidity, failure to maintain detergent resistant membrane fraction, and hypersensitivity to heat stress. These c14dm(-) mutants showed severely reduced virulence in mice but were highly resistant to itraconazole and amphotericin B, two drugs targeting sterol synthesis. Our findings suggest that the accumulation of toxic sterol intermediates in c14dm(-) causes strong membrane perturbation and significant vulnerability to stress. The new knowledge may help improve the efficacy of current drugs against pathogenic protozoa by exploiting the fitness loss associated with drug resistance.

Origin of animal multicellularity: precursors, causes, consequences—the choanoflagellate/sponge transition, neurogenesis and the Cambrian explosion

PubMed Central

Cavalier-Smith, Thomas

2017-01-01

Evolving multicellularity is easy, especially in phototrophs and osmotrophs whose multicells feed like unicells. Evolving animals was much harder and unique; probably only one pathway via benthic ‘zoophytes’ with pelagic ciliated larvae allowed trophic continuity from phagocytic protozoa to gut-endowed animals. Choanoflagellate protozoa produced sponges. Converting sponge flask cells mediating larval settling to synaptically controlled nematocysts arguably made Cnidaria. I replace Haeckel's gastraea theory by a sponge/coelenterate/bilaterian pathway: Placozoa, hydrozoan diploblasty and ctenophores were secondary; stem anthozoan developmental mutations arguably independently generated coelomate bilateria and ctenophores. I emphasize animal origin's conceptual aspects (selective, developmental) related to feeding modes, cell structure, phylogeny of related protozoa, sequence evidence, ecology and palaeontology. Epithelia and connective tissue could evolve only by compensating for dramatically lower feeding efficiency that differentiation into non-choanocytes entails. Consequentially, larger bodies enabled filtering more water for bacterial food and harbouring photosynthetic bacteria, together adding more food than cell differentiation sacrificed. A hypothetical presponge of sessile triploblastic sheets (connective tissue sandwiched between two choanocyte epithelia) evolved oogamy through selection for larger dispersive ciliated larvae to accelerate benthic trophic competence and overgrowing protozoan competitors. Extinct Vendozoa might be elaborations of this organismal grade with choanocyte-bearing epithelia, before poriferan water channels and cnidarian gut/nematocysts/synapses evolved. This article is part of the themed issue ‘Evo-devo in the genomics era, and the origins of morphological diversity’. PMID:27994119

Culturing Protozoa.

ERIC Educational Resources Information Center

Stevenson, Paul

1980-01-01

Compares various nutrient media, growth conditions, and stock solutions used in culturing protozoa. A hay infusion in Chalkey's solution maintained at a stable temperature is recommended for producing the most dense and diverse cultures. (WB)

Dual origin of gut proteases in Formosan subterranean termites (Coptotermes formosanus Shiraki) (Isoptera: Rhinotermitidae).

PubMed

Sethi, Amit; Xue, Qing-Gang; La Peyre, Jerome F; Delatte, Jennifer; Husseneder, Claudia

2011-07-01

Cellulose digestion in lower termites, mediated by carbohydrases originating from both termite and endosymbionts, is well characterized. In contrast, limited information exists on gut proteases of lower termites, their origins and roles in termite nutrition. The objective of this study was to characterize gut proteases of the Formosan subterranean termite (Coptotermes formosanus Shiraki) (Isoptera: Rhinotermitidae). The protease activity of extracts from gut tissues (fore-, mid- and hindgut) and protozoa isolated from hindguts of termite workers was quantified using hide powder azure as a substrate and further characterized by zymography with gelatin SDS-PAGE. Midgut extracts showed the highest protease activity followed by the protozoa extracts. High level of protease activity was also detected in protozoa culture supernatants after 24 h incubation. Incubation of gut and protozoa extracts with class-specific protease inhibitors revealed that most of the proteases were serine proteases. All proteolytic bands identified after gelatin SDS-PAGE were also inhibited by serine protease inhibitors. Finally, incubation with chromogenic substrates indicated that extracts from fore- and hindgut tissues possessed proteases with almost exclusively trypsin-like activity while both midgut and protozoa extracts possessed proteases with trypsin-like and subtilisin/chymotrypsin-like activities. However, protozoa proteases were distinct from midgut proteases (with different molecular mass). Our results suggest that the Formosan subterranean termite not only produces endogenous proteases in its gut tissues, but also possesses proteases originating from its protozoan symbionts. Copyright © 2011 Elsevier Inc. All rights reserved.

Technical note: Protozoa-specific antibodies raised in sheep plasma bind to their target protozoa in the rumen.

PubMed

Williams, Y J; Rea, S M; Popovski, S; Skillman, L C; Wright, A-D G

2014-12-01

Binding of IgG antibodies to Entodinium spp. in the rumen of sheep (Ovis aries) was investigated by adding IgG, purified from plasma, directly into the rumen. Plasma IgG was sourced from sheep that had or had not been immunized with a vaccine containing whole fixed Entodinium spp. cells. Ruminal fluid was sampled approximately 2 h after each antibody dosing. Binding of protozoa by a specific antibody was detected using an indirect fluorescent antibody test. An antibody titer in the ruminal fluid was determined by ELISA, and the concentration of ruminal fluid ammonia-N and ruminal pH were also determined. Entodinium spp. and total protozoa from IgG-infused sheep were enumerated by microscopic counts. Two-hourly additions of IgG maintained a low antibody titer in the rumen for 12 h and the binding of the antibody to the rumen protozoa was demonstrated. Increased ammonia-N concentrations and altered ruminal fluid pH patterns indicated that additional fermentation of protein was occurring in the rumen after addition of IgG. No reduction in numbers of Entodinium spp. was observed (P>0.05). Although binding of antibodies to protozoa has been demonstrated in the rumen, it is unclear how much cell death occurred. On the balance of probability, it would appear that the antibody was degraded or partially degraded, and the impact of this on protozoal populations and the measurement of a specific titer is also unclear.

World Health Organization Estimates of the Global and Regional Disease Burden of 11 Foodborne Parasitic Diseases, 2010: A Data Synthesis.

PubMed

Torgerson, Paul R; Devleesschauwer, Brecht; Praet, Nicolas; Speybroeck, Niko; Willingham, Arve Lee; Kasuga, Fumiko; Rokni, Mohammad B; Zhou, Xiao-Nong; Fèvre, Eric M; Sripa, Banchob; Gargouri, Neyla; Fürst, Thomas; Budke, Christine M; Carabin, Hélène; Kirk, Martyn D; Angulo, Frederick J; Havelaar, Arie; de Silva, Nilanthi

2015-12-01

Foodborne diseases are globally important, resulting in considerable morbidity and mortality. Parasitic diseases often result in high burdens of disease in low and middle income countries and are frequently transmitted to humans via contaminated food. This study presents the first estimates of the global and regional human disease burden of 10 helminth diseases and toxoplasmosis that may be attributed to contaminated food. Data were abstracted from 16 systematic reviews or similar studies published between 2010 and 2015; from 5 disease data bases accessed in 2015; and from 79 reports, 73 of which have been published since 2000, 4 published between 1995 and 2000 and 2 published in 1986 and 1981. These included reports from national surveillance systems, journal articles, and national estimates of foodborne diseases. These data were used to estimate the number of infections, sequelae, deaths, and Disability Adjusted Life Years (DALYs), by age and region for 2010. These parasitic diseases, resulted in 48.4 million cases (95% Uncertainty intervals [UI] of 43.4-79.0 million) and 59,724 (95% UI 48,017-83,616) deaths annually resulting in 8.78 million (95% UI 7.62-12.51 million) DALYs. We estimated that 48% (95% UI 38%-56%) of cases of these parasitic diseases were foodborne, resulting in 76% (95% UI 65%-81%) of the DALYs attributable to these diseases. Overall, foodborne parasitic disease, excluding enteric protozoa, caused an estimated 23.2 million (95% UI 18.2-38.1 million) cases and 45,927 (95% UI 34,763-59,933) deaths annually resulting in an estimated 6.64 million (95% UI 5.61-8.41 million) DALYs. Foodborne Ascaris infection (12.3 million cases, 95% UI 8.29-22.0 million) and foodborne toxoplasmosis (10.3 million cases, 95% UI 7.40-14.9 million) were the most common foodborne parasitic diseases. Human cysticercosis with 2.78 million DALYs (95% UI 2.14-3.61 million), foodborne trematodosis with 2.02 million DALYs (95% UI 1.65-2.48 million) and foodborne toxoplasmosis with 825,000 DALYs (95% UI 561,000-1.26 million) resulted in the highest burdens in terms of DALYs, mainly due to years lived with disability. Foodborne enteric protozoa, reported elsewhere, resulted in an additional 67.2 million illnesses or 492,000 DALYs. Major limitations of our study include often substantial data gaps that had to be filled by imputation and suffer from the uncertainties that surround such models. Due to resource limitations it was also not possible to consider all potentially foodborne parasites (for example Trypanosoma cruzi). Parasites are frequently transmitted to humans through contaminated food. These estimates represent an important step forward in understanding the impact of foodborne diseases globally and regionally. The disease burden due to most foodborne parasites is highly focal and results in significant morbidity and mortality among vulnerable populations.

Protistan Bacterivory in an Oligomesotrophic Lake: Importance of Attached Ciliates and Flagellates

PubMed

Carrias; Amblard; Bourdier

1996-05-01

Seasonal and depth variations of the abundance, biomass, and bacterivory of protozoa (heterotrophic and mixotrophic flagellates and ciliates) were determined during thermal stratification in an oligomesotrophic lake (Lake Pavin, France). Maximal densities of heterotrophic flagellates (1.9x10(3) cells ml-1) and ciliates (6.1 cells ml-1) were found in the metalimnion. Pigmented flagellates dominated the flagellate biomass in the euphotic zone. Community composition of ciliated protists varied greatly with depth, and both the abundance and biomass of ciliates was dominated by oligotrichs. Heterotrophic flagellates dominated grazing, accounting for 84% of total protistan bacterivory. Maximal grazing impact of heterotrophic flagellates was 18.9x10(6) bacteria 1(-1)h-1. On average, 62% of nonpigmented flagellates were found to ingest particles. Ciliates and mixotrophic flagellates averaged 13% and 3% of protistan bacterivory, respectively. Attached protozoa (ciliates and flagellates) were found to colonize the diatom Asterionella formosa. Attached bacterivores had higher ingestion rates than free bacterivorous protozoa and may account for 66% of total protozoa bacterivory. Our results indicated that even in low numbers, epibiotic protozoa may have a major grazing impact on free bacteria.

The protozooplankton-ichthyoplankton trophic link: an overlooked aspect of aquatic food webs.

PubMed

Montagnes, David J S; Dower, John F; Figueiredo, Gisela M

2010-01-01

Since the introduction of the microbial loop concept, awareness of the role played by protozooplankton in marine food webs has grown. By consuming bacteria, and then being consumed by metazooplankton, protozoa form a trophic link that channels dissolved organic material into the "classic" marine food chain. Beyond enhancing energy transfer to higher trophic levels, protozoa play a key role in improving the food quality of metazooplankton. Here, we consider a third role played by protozoa, but one that has received comparatively little attention: that as prey items for ichthyoplankton. For >100 years it has been known that fish larvae consume protozoa. Despite this, fisheries scientists and biological oceanographers still largely ignore protozoa when assessing the foodweb dynamics that regulate the growth and survival of larval fish. We review evidence supporting the importance of the protozooplankton-ichthyoplankton link, including examples from the amateur aquarium trade, the commercial aquaculture industry, and contemporary studies of larval fish. We then consider why this potentially important link continues to receive very little attention. We conclude by offering suggestions for quantifying the importance of the protozooplankton-ichthyoplankton trophic link, using both existing methods and new technologies.

Effects of some air pollutants and meteorological conditions on airborne algae and protozoa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, P.E.

1973-10-01

The effects of meteorological conditions and specific air pollutants on the viability of airborne algae and protozoa were investigated. Such investigations will be of interest to medical researchers because these organisms are the source of many allergies. The three air pollutants that were continuously measured and recorded were sulfur, hydrocarbons, and particulate matter. During the experiment, 25 different species of algae and 19 species of protozoa were collected from the atmosphere and cultured at the Westinghouse environmental Station Laboratory in Raleigh, North Carolina. The algae and protozoa were collected over a one-year period (Jan-Dec 1971) by using a sequential samplermore » that moved air through a membrane filter at the rate of 15 ft/sup 3//hr. Every two hours a new filter was sequentially moved in to replace the old one. The results indicated a relationship between wind speed, wind direction, temperature, dewpoint, particulate matter, barometric pressure, and rainfall to the percent frequency of positive culture tubes and number of cell/ft/sup 3/ of air. Further studies are necessary to determine the interrelationships between the physical and chemical character of various air masses and their effect on the survival of algae and protozoa.« less

Sheep fed with banana leaf hay reduce ruminal protozoa population.

PubMed

Freitas, Cláudio Eduardo Silva; Duarte, Eduardo Robson; Alves, Dorismar David; Martinele, Isabel; D'Agosto, Marta; Cedrola, Franciane; de Moura Freitas, Angélica Alves; Dos Santos Soares, Franklin Delano; Beltran, Makenzi

2017-04-01

A ciliate protozoa suppression can reduce methane production increasing the energy efficiency utilization by ruminants. The physicochemical characteristics of rumen fluid and the profile of the rumen protozoa populations were evaluated for sheep fed banana leaf hay in replacement of the Cynodon dactylon cv. vaqueiro hay. A total of 30 male sheep were raised in intensive system during 15 days of adaptation and 63 days of experimental period. The animals were distributed in a completely randomized design that included six replicates of five treatments with replacement levels (0, 25, 50, 75, and 100%) of the grass vaquero for the banana leaf hay. Samples of fluid were collected directly from the rumen with sterile catheters. Color, odor, viscosity, and the methylene blue reduction potential (MBRP) were evaluated and pH estimated using a digital potentiometer. After decimal dilutions, counts of genus protozoa were performed in Sedgewick Rafter chambers. The averages of pH, MBRP, color, odor, and viscosity were not influenced by the inclusion of the banana leaf hay. However, the total number of protozoa and Entodinium spp. population significantly decreased at 75 and 100% inclusions of banana leaf hay as roughage.

Prevalence of intestinal parasites in Isfahan city, central Iran, 2014.

PubMed

Jafari, Rasool; Sharifi, Forough; Bagherpour, Bahram; Safari, Marzieh

2016-09-01

Intestinal parasites are important enteric pathogens. Poverty, low quality of food and water supply and poor sanitation systems are the important factors associated with intestinal parasitic infections. These kinds of infections can be a good index for hygienic and sanitation status of the society. This study aimed to determine the prevalence of intestinal parasitic infections among humans referred to Dr. Sharifi Clinical Laboratory, Isfahan, Iran, 2014. In this cross sectional study, 652 fecal samples (286 males and 366 females) from humans who had stool examination test from January to August 2014 were chosen. Microscopic examination for parasitic infections has been carried out using wet mount method. Indistinguishable samples underwent trichrome staining method for accurate identification of protozoa. Intestinal parasitic infections were observed in 68 (10.42 %) out of 652 studied humans. Forty eight Blastocystis hominis (7.36 %), thirteen Endolimax nana (1.99 %), nine Giardia lamblia (1.38 %), five Entamoeba coli (0.76 %), four Chilomastix mesnili (0.61 %) and two Iodamoeba butschlii (0.15 %) were the observed protozoa in the studied population. B. hominis, E. nana and C. mesnili were found to be significantly more prevalent in people with loose stool specimen. Considering the helminthic infections, only one case (0.15 %) that was excreted Taenia saginata proglottids has been documented among 652 studied humans. Based on the findings of the present study intestinal parasitic infections in Isfahan city has been dramatically decreased over the past years and shows a good hygienic and sanitation status of the city.

Patients with gastrointestinal complains due to enteric parasites, with reference to Entamoeba histolytica/dispar as dected by ELISA E. histolytica adhesion in stool.

PubMed

El-Kadi, Mohammad A; Dorrah, Ahmad O; Shoukry, Nahla M

2006-04-01

A total of 210 patients with gastrointestinal troubles, of both sex and a mean age of 32 +/- 6.1 years, selected from the outpatient's clinics of Al-Azhar University Hospitals. 115 (54.76%) had dysentery, 95 (45.23%) did not have dysentery, 15 (14%) suffered flatulence, 20 (9.52%) had epi-gastric pain, 19 (9.05%) had vague abdominal pain, 5 vomiting (5.2%) and 10 (4.9%) had fever. Two symptoms were in 29 (13.81%) patients and three symptoms in 12 (5.71%). Of the 210 patients, 20 (9.9%) had helminthes infection, 121 (57.6%) had intestinal protozoa and 69 (32.9%) had no parasitic infection. Of these parasite-free patients, 16 had Shigella sp. and nine had Campylobacter sp. Of the patients with intestinal protozoa, 34 (16.2%) had E. histolytica/dispar by stool examination of stained smears. By using ELISA for detection of E. histolytica adhesion in stool samples of 115 with diarrhea only 18 had true E. histolytica infection and of 3 without diarrhea only one had E. histolytica infection. Mean-while, ELISA did not cross-reacted E. coli, Giardia lamblia, Cryptosporidium parvum, Endolimax nana or Blastocystis hominis. So, ELISA for detection of E. histolytica adhesion in stool samples was more specific than microscopy and safe direction to the E. histolytica treatment. Apart from intestinal protozoan and bacteria, helminthes were seen in stool analysis. These were Schistosoma mansoni (0.95%), Capillaria sp. (0.95%), Enterobius vermicularis (1.90%) macroscopically, Hymenolepis nana (4.3%) and Ascaris lumbricoides (1.43%).

Metronidazole and the immune system.

PubMed

Shakir, L; Javeed, A; Ashraf, M; Riaz, A

2011-06-01

Metronidazole (MTZ) is a nitroimidazole antibiotic used mainly for the treatment of infections caused by susceptible organisms, particularly anaerobic bacteria and protozoa. Distinct from its antibiotic, amoebicidal, and antiprotozoal effects, MTZ displays immunopharmacological behaviour. This review outlines multiple effects of MTZ on different aspects of immunity, including innate and acquired immunity, and also highlights the immunopharmacological behaviour of MTZ in terms of its relevance to inflammation, delayed type hypersensitivity (DTH) and graft versus host disease (GVHD).

21 CFR 558.555 - Semduramicin.

Code of Federal Regulations, 2011 CFR

2011-04-01

... paragraph (d)(1) of this section; for prevention of necrotic enteritis caused by Clostridium perfringens... enteritis caused by Clostridium perfringens susceptible to virginiamycin; for increased rate of weight gain...; for prevention of necrotic enteritis caused by C. perfringens susceptible to virginiamycin. Feed...

21 CFR 558.555 - Semduramicin.

Code of Federal Regulations, 2012 CFR

2012-04-01

... paragraph (d)(1) of this section; for prevention of necrotic enteritis caused by Clostridium perfringens... enteritis caused by Clostridium perfringens susceptible to virginiamycin; for increased rate of weight gain...; for prevention of necrotic enteritis caused by C. perfringens susceptible to virginiamycin. Feed...

21 CFR 558.555 - Semduramicin.

Code of Federal Regulations, 2013 CFR

2013-04-01

... paragraph (d)(1) of this section; for prevention of necrotic enteritis caused by Clostridium perfringens... enteritis caused by Clostridium perfringens susceptible to virginiamycin; for increased rate of weight gain...; for prevention of necrotic enteritis caused by C. perfringens susceptible to virginiamycin. Feed...

The Intestinal Microbiota Plays a Role in Salmonella-Induced Colitis Independent of Pathogen Colonization

PubMed Central

Ferreira, Rosana B. R.; Gill, Navkiran; Willing, Benjamin P.; Antunes, L. Caetano M.; Russell, Shannon L.; Croxen, Matthew A.; Finlay, B. Brett

2011-01-01

The intestinal microbiota is composed of hundreds of species of bacteria, fungi and protozoa and is critical for numerous biological processes, such as nutrient acquisition, vitamin production, and colonization resistance against bacterial pathogens. We studied the role of the intestinal microbiota on host resistance to Salmonella enterica serovar Typhimurium-induced colitis. Using multiple antibiotic treatments in 129S1/SvImJ mice, we showed that disruption of the intestinal microbiota alters host susceptibility to infection. Although all antibiotic treatments caused similar increases in pathogen colonization, the development of enterocolitis was seen only when streptomycin or vancomycin was used; no significant pathology was observed with the use of metronidazole. Interestingly, metronidazole-treated and infected C57BL/6 mice developed severe pathology. We hypothesized that the intestinal microbiota confers resistance to infectious colitis without affecting the ability of S. Typhimurium to colonize the intestine. Indeed, different antibiotic treatments caused distinct shifts in the intestinal microbiota prior to infection. Through fluorescence in situ hybridization, terminal restriction fragment length polymorphism, and real-time PCR, we showed that there is a strong correlation between the intestinal microbiota composition before infection and susceptibility to Salmonella-induced colitis. Members of the Bacteroidetes phylum were present at significantly higher levels in mice resistant to colitis. Further analysis revealed that Porphyromonadaceae levels were also increased in these mice. Conversely, there was a positive correlation between the abundance of Lactobacillus sp. and predisposition to colitis. Our data suggests that different members of the microbiota might be associated with S. Typhimurium colonization and colitis. Dissecting the mechanisms involved in resistance to infection and inflammation will be critical for the development of therapeutic and preventative measures against enteric pathogens. PMID:21633507

Symbiosis and Rumen Protozoa

ERIC Educational Resources Information Center

Dillon, Raymond D.

1970-01-01

Protozoa inhabiting the rumen of large grazing animals can be used to illustrate symbiotic animal associations. Gives a key to the ciliates most commonly found, several drawings, and a chart relating rumen fauna to the phylogenetic tree of the hosts. (EB)

Regulation of gene expression in protozoa parasites.

PubMed

Gomez, Consuelo; Esther Ramirez, M; Calixto-Galvez, Mercedes; Medel, Olivia; Rodríguez, Mario A

2010-01-01

Infections with protozoa parasites are associated with high burdens of morbidity and mortality across the developing world. Despite extensive efforts to control the transmission of these parasites, the spread of populations resistant to drugs and the lack of effective vaccines against them contribute to their persistence as major public health problems. Parasites should perform a strict control on the expression of genes involved in their pathogenicity, differentiation, immune evasion, or drug resistance, and the comprehension of the mechanisms implicated in that control could help to develop novel therapeutic strategies. However, until now these mechanisms are poorly understood in protozoa. Recent investigations into gene expression in protozoa parasites suggest that they possess many of the canonical machineries employed by higher eukaryotes for the control of gene expression at transcriptional, posttranscriptional, and epigenetic levels, but they also contain exclusive mechanisms. Here, we review the current understanding about the regulation of gene expression in Plasmodium sp., Trypanosomatids, Entamoeba histolytica and Trichomonas vaginalis.

Occurrence and removal efficiency of parasitic protozoa in Swedish wastewater treatment plants.

PubMed

Berglund, Björn; Dienus, Olaf; Sokolova, Ekaterina; Berglind, Emma; Matussek, Andreas; Pettersson, Thomas; Lindgren, Per-Eric

2017-11-15

Giardia intestinalis, Cryptosporidium spp., Entamoeba histolytica and Dientamoeba fragilis are parasitic protozoa and causative agents of gastroenteritis in humans. G. intestinalis and Cryptosporidium spp. in particular are the most common protozoa associated with waterborne outbreaks in high-income countries. Surveillance of protozoan prevalence in wastewater and evaluation of wastewater treatment removal efficiencies of protozoan pathogens is therefore imperative for assessment of human health risk. In this study, influent and effluent wastewater samples from three wastewater treatment plants in Sweden were collected over nearly one year and assessed for prevalence of parasitic protozoa. Quantitative real-time PCR using primers specific for the selected protozoa Cryptosporidium spp., G. intestinalis, E. histolytica, Entamoeba dispar and D. fragilis was used for protozoan DNA detection and assessment of wastewater treatment removal efficiencies. Occurrence of G. intestinalis, E. dispar and D. fragilis DNA was assessed in both influent (44, 30 and 39 out of 51 samples respectively) and effluent wastewater (14, 9 and 33 out of 51 samples respectively) in all three wastewater treatment plants. Mean removal efficiencies of G. intestinalis, E. dispar and D. fragilis DNA quantities, based on all three wastewater treatment plants studied varied between 67 and 87%, 37-75% and 20-34% respectively. Neither E. histolytica nor Cryptosporidium spp. were detected in any samples. Overall, higher quantities of protozoan DNA were observed from February to June 2012. The high prevalence of protozoa in influent wastewater indicates the need for continued monitoring of these pathogens in wastewater-associated aquatic environments to minimise the potential risk for human infection. Copyright © 2017 Elsevier B.V. All rights reserved.

MEASURE OCCURRENCE AND EXPOSURE TO CCL-RELATED, EMERGING AND REGULATED WATERBORNE HUMAN PROTOZOA

EPA Science Inventory

Pathogenic waterborne protozoa (Giardia, Cryptosporidium) have been identified as significant etiological agents in the transmission of waterborne disease. Microsporidians, which are on the Agency's Contaminant Candidate List, are obligate intracellular parasites of invertebrate...

The SPI-1-like Type III secretion system: more roles than you think

PubMed Central

Egan, Frank; Barret, Matthieu; O’Gara, Fergal

2014-01-01

The type III secretion system (T3SS) is a protein delivery system which is involved in a wide spectrum of interactions, from mutualism to pathogenesis, between Gram negative bacteria and various eukaryotes, including plants, fungi, protozoa and mammals. Various phylogenetic families of the T3SS have been described, including the Salmonella Pathogenicity Island 1 family (SPI-1). The SPI-1 T3SS was initially associated with the virulence of enteric pathogens, but is actually found in a diverse array of bacterial species, where it can play roles in processes as different as symbiotic interactions with insects and colonization of plants. We review the multiple roles of the SPI-1 T3SS and discuss both how these discoveries are changing our perception of the SPI-1 family and what impacts this has on our understanding of the specialization of the T3SS in general. PMID:24575107

The SPI-1-like Type III secretion system: more roles than you think.

PubMed

Egan, Frank; Barret, Matthieu; O'Gara, Fergal

2014-01-01

The type III secretion system (T3SS) is a protein delivery system which is involved in a wide spectrum of interactions, from mutualism to pathogenesis, between Gram negative bacteria and various eukaryotes, including plants, fungi, protozoa and mammals. Various phylogenetic families of the T3SS have been described, including the Salmonella Pathogenicity Island 1 family (SPI-1). The SPI-1 T3SS was initially associated with the virulence of enteric pathogens, but is actually found in a diverse array of bacterial species, where it can play roles in processes as different as symbiotic interactions with insects and colonization of plants. We review the multiple roles of the SPI-1 T3SS and discuss both how these discoveries are changing our perception of the SPI-1 family and what impacts this has on our understanding of the specialization of the T3SS in general.

Ultrastructural observations on giardiasis in a mouse model. II. Endosymbiosis and organelle distribution in Giardia muris and Giardia lamblia.

PubMed

Nemanic, P C; Owen, R L; Stevens, D P; Mueller, J C

1979-08-01

Ultrastructural observations of Giardia muris in a mouse model revealed endosymbiotic microbes not previously reported in Giardia. Endosymbionts 240--360 nm wide, 600--1,400 nm long, and with an internal structure similar to that of bacilli were not seen entering Giardia but were found and appeared to divide within Giardia. No evidence was found of digestion of the endosymbionts by the giardia host in either the trophozoite or the cyst form. Endosymbionts were concentrated centrally around the nuclear area and were uncommon in peripheral feeding regions. The same cellular organelles seen in G. muris were found in Giardia lamblia from human jejunal biopsy material, but no endosymbionts were identified in G. lamblia trophozoites from the seven patients examined. Endosymbionts within Giardia may be found to alter trophozoite pathogenicity, metabolism, range of infectivity, antigenic surface characteristics, and host specificity, as they do in other protozoa.

HACCP (Hazard Analysis and Critical Control Points) to guarantee safe water reuse and drinking water production--a case study.

PubMed

Dewettinck, T; Van Houtte, E; Geenens, D; Van Hege, K; Verstraete, W

2001-01-01

To obtain a sustainable water catchment in the dune area of the Flemish west coast, the integration of treated domestic wastewater in the existing potable water production process is planned. The hygienic hazards associated with the introduction of treated domestic wastewater into the water cycle are well recognised. Therefore, the concept of HACCP (Hazard Analysis and Critical Control Points) was used to guarantee hygienically safe drinking water production. Taking into account the literature data on the removal efficiencies of the proposed advanced treatment steps with regard to enteric viruses and protozoa and after setting high quality limits based on the recent progress in quantitative risk assessment, the critical control points (CCPs) and points of attention (POAs) were identified. Based on the HACCP analysis a specific monitoring strategy was developed which focused on the control of these CCPs and POAs.

Molecular and chemical dialogues in bacteria-protozoa interactions

USDA-ARS?s Scientific Manuscript database

Soil-dwelling Pseudomonas fluorescens produce lipopeptide surfactants (LPs) with broad-spectrum antimicrobial activities. Recent studies suggested that LPs provide protection to P. fluorescens strain SS101 against grazing by the predatory protozoa Naegleria americana, both in vitro and in rhizospher...

Novel antiprotozoal products: imidazole and benzimidazole N-oxide derivatives and related compounds.

PubMed

Aguirre, Gabriela; Boiani, Mariana; Cerecetto, Hugo; Gerpe, Alejandra; González, Mercedes; Sainz, Yolanda Fernández; Denicola, Ana; De Ocáriz, Carmen Ochoa; Nogal, Juan José; Montero, David; Escario, José Antonio

2004-05-01

The syntheses and biological evaluation of the first anti-protozoa imidazole N-oxide and benzimidazole N-oxide and their derivatives are reported. They were tested in vitro against two different protozoa, Trypanosoma cruzi and Trichomonas vaginalis. Derivative 7c, ethyl-1-(i-butyloxycarbonyloxy)-6-nitrobenzimid-azole-2-carboxylate, displayed activity on both protozoa. Lipophilicity and redox potential were experimentally determined in order to study the relationship with activity of the compounds. These properties are well related with the observed bioactivity. Imidazole and benzimidazole N-oxide derivatives are becoming leaders for further chemical modifications and advanced biological studies.

Ticks of Medical Importance Occurring in the Western Hemisphere

DTIC Science & Technology

1987-10-01

disease agents such as protozoa, viruses, bacteria , rickettsiae and toxins. Ticks may also cause Irritation and discomfnrt directly as a result of their...1959). 64. Bustamante, M.E., and G. Varela. Une nueva rickettslosis en Mexico. Existencia do a& fiebra manchada americana en los estados do Sinaloa...2: 76-81 (1951). 76. Serre, P.A. Insectes piquantes et parasites au Costa Rica. Bull Mus Hist Mat, Paris. 27: 170-172 (1921). * 77. Cerny, V. Nuevas

Cryptosporidiosis as threatening health problem: A review

PubMed Central

Rossle, Nurul Fariza; Latif, Baha

2013-01-01

The protozoa under the genus Cryptosporidium is a zoonotic apicomplexan obligate intracellular parasite. Cryptosporidiosis, the term used to designate infection caused by Cryptosporidium sp., is considered as one of the most common food and waterborne diseases with worldwide spread, acting as a common cause of diarrhoea in animals and man. In immunocompetent individuals, Cryptosporidium typically induces self-limiting diarrhoea, which may resolve on its own after 2-3 d. However, cryptosporidiosis may turn life-threatening and subsequently lead to death in small children, the elderly and immunocompromised person, especially in AIDS patient. The diagnosis for Cryptosporidium infection is usually carried out through examination of stool for the presence of oocysts which measured 4-6 µm with spherical appearance. Morphometric identification is often difficult because of the diminutive size and obscure internal structure of the protozoa. Often, the identification of Cryptosporidium is realised through the combination of methods incorporating data from morphometrics, molecular techniques, and host specificity. However, limitations to some of these techniques still exist whether because of cost, duration, expertise, or reliability. Drugs combination is implemented in treatment of cryptosporidiosis. The efficiency of paromomycin, an aminocyclitol antibiotic isolated from Streptomyces, can be effective when combined use with protease inhibitors or recombinant IL-12. Since there is no drug that achieves the complete removal of Cryptosporidium from the host, supportive therapy was preferred in both human and domestic animals.

Histological survey of symbionts and other conditions of pod razor clam Ensis siliqua (Linnaeus, 1758) in Galicia (NW Spain).

PubMed

Ruiz, Maite; Darriba, Susana; Rodríguez, Rosana; López, Carmen

2013-01-01

The aim of the present study was to carry out a survey of parasites and other conditions affecting pod razor clam populations, Ensis siliqua, in two beds from Galicia (NW Spain). In Galicia, the production of E. siliqua has increased in recent years due to the development of specific plans for its exploitation, however few and quite recent pathological studies have been carried out in this species. The results of this study showed the presence of different protozoa as the more prevalent group, especially Nematopsis sp. gregarines, unidentified branchial protozoa, renal coccidia and Trichodina sp. ciliates. Larval stages of trematodes and neoplastic disorders were also observed with lower prevalences. Furthermore, an ultrastructural analysis of two types of unidentified basophilic inclusions, both found in the digestive gland, revealed the presence of icosahedral viral particles and prokaryotic organisms, respectively. None of the parasites detected in E. siliqua from this study was notifiable to the World Organisation for Animal Health (OIE) and the majority of the symbionts and conditions observed in their tissues did not cause host damage. Nevertheless, parasites like bucephalid digenean sporocysts, viral inclusions, prokaryotic infections, disseminated neoplasm or germinoma detected in some samples could cause moderate or severe damage to the host depending on the intensity of infection. Copyright © 2012 Elsevier Inc. All rights reserved.

Ruminal protozoal contribution to the duodenal flow of fatty acids following feeding of steers on forages differing in chloroplast content.

PubMed

Huws, S A; Lee, M R F; Kingston-Smith, A H; Kim, E J; Scott, M B; Tweed, J K S; Scollan, N D

2012-12-28

Ruminant products are criticised for their SFA content relative to PUFA, although n-6:n-3 PUFA is desirable for human health ( < 4). Rumen protozoa are rich in unsaturated fatty acids due to engulfment of PUFA-rich chloroplasts. Increasing the chloroplast content of rumen protozoa offers a potentially novel approach to enhance PUFA flow to the duodenum and subsequent incorporation into meat and milk. We evaluated protozoal contribution to duodenal n-3 PUFA flow due to intracellular chloroplast content. A total of six Holstein × Friesian steers were fed, in a two-period changeover design, either straw:concentrate (S:C, 60:40; DM basis; S:C, low chloroplast) or fresh perennial ryegrass (PRG; high chloroplast). Following 12 d adaptation to diet, ruminal protozoal and whole duodenal samples were obtained. N and fatty acid content of whole duodenum and rumen protozoal samples were assessed and protozoal 18S rDNA quantitative PCR performed, enabling calculation of protozoal N flow. The ratio of individual fatty acids:N in rumen protozoal samples was calculated to obtain protozoal fatty acid flows. Based on total fatty acid flow, contribution (%) of protozoa to individual fatty acid flows was calculated. Protozoal fatty acid data and microscopical observations revealed that protozoa were enriched with 18 : 3n-3 following PRG feeding, compared with the S:C diet, due to increased intracellular chloroplast content. However, duodenal protozoal 18S rDNA concentration post PRG feeding was low, indicating rumen retention of the protozoa. Nutrition influences the 18 : 3n-3 content of protozoa; the challenge is to increase protozoal flow to the small intestine, while maintaining sustainable rumen densities.

Ion Trapping of Amines in Protozoa: A Novel Removal Mechanism for Micropollutants in Activated Sludge.

PubMed

Gulde, Rebekka; Anliker, Sabine; Kohler, Hans-Peter E; Fenner, Kathrin

2018-01-02

To optimize removal of organic micropollutants from the water cycle, understanding the processes during activated sludge treatment is essential. In this study, we hypothesize that aliphatic amines, which are highly abundant among organic micropollutants, are partly removed from the water phase in activated sludge through ion trapping in protozoa. In ion trapping, which has been extensively investigated in medical research, the neutral species of amine-containing compounds diffuse through the cell membrane and further into acidic vesicles present in eukaryotic cells such as protozoa. There they become trapped because diffusion of the positively charged species formed in the acidic vesicles is strongly hindered. We tested our hypothesis with two experiments. First, we studied the distribution of the fluorescent amine acridine orange in activated sludge by confocal fluorescence imaging. We observed intense fluorescence in distinct compartments of the protozoa, but not in the bacterial biomass. Second, we investigated the distribution of 12 amine-containing and eight control micropollutants in both regular activated sludge and sludge where the protozoa had been inactivated. In contrast to most control compounds, the amine-containing micropollutants displayed a distinctly different behavior in the noninhibited sludge compared to the inhibited one: (i) more removal from the liquid phase; (ii) deviation from first-order kinetics for the removal from the liquid phase; and (iii) higher amounts in the solid phase. These results provide strong evidence that ion trapping in protozoa occurs and that it is an important removal mechanism for amine-containing micropollutants in batch experiments with activated sludge that has so far gone unnoticed. We expect that our findings will trigger further investigations on the importance of this process in full-scale wastewater treatment systems, including its relevance for accumulation of ammonium.

Can fungal zoospores be the source of energy for the rumen protozoa Eudiplodinium maggii?

PubMed

Miltko, Renata; Bełżecki, Grzegorz; Kowalik, Barbara; Michałowski, Tadeusz

2014-10-01

Results of our earlier studies showed the ability of ciliates Eudiplodinium maggii to digest and metabolize commercial chitin. The natural source of this polysaccharide in the rumen are fungi. The objectives of present research were to determine the effect of fungal zoospores on the survival and population density of E. maggii to quantify the concentration of chitin in the cells of protozoa and to examine the ability of E. maggii, to ferment chitin of fungal zoospores. The cultivation experiment showed that the survival of protozoa was shorter than 4 days when the culture medium was composed of buffer solution and lyophilized fungal spores. An enrichment of this medium with wheat gluten prolonged the survival of ciliates up to 8 days. The supplementation of the last medium with meadow hay enabled the protozoa to survive for 28 days but a positive effect was observed only during the last 8 days of experiment. The chitin content was 0.27 ng and 0.21-0.35 ng per single zoospore and ciliate, respectively. An increase in the concentration of volatile fatty acids (VFA) was found when protozoa were incubated with zoospores. The production rate of VFA was 46.3 pM/protozoan per h whereas the endogenous production did not exceed 31 pM/protozoan per h. The molar proportion of acetic acid was 77.7% and these of butyric and propionic acids-12.2 and 11.0%, respectively. The obtained results make it evident that carbohydrates present in fungal zoospores were utilized by protozoa in energy yielding processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Free-Living Protozoa in Two Unchlorinated Drinking Water Supplies, Identified by Phylogenic Analysis of 18S rRNA Gene Sequences▿ †

PubMed Central

Valster, Rinske M.; Wullings, Bart A.; Bakker, Geo; Smidt, Hauke; van der Kooij, Dick

2009-01-01

Free-living protozoan communities in water supplies may include hosts for Legionella pneumophila and other undesired bacteria, as well as pathogens. This study aimed at identifying free-living protozoa in two unchlorinated groundwater supplies, using cultivation-independent molecular approaches. For this purpose, samples (<20°C) of treated water, distributed water, and distribution system biofilms were collected from supply A, with a low concentration of natural organic matter (NOM) (<0.5 ppm of C), and from supply B, with a high NOM concentration (7.9 ppm of C). Eukaryotic communities were studied using terminal restriction fragment length polymorphism and clone library analyses of partial 18S rRNA gene fragments and a Hartmannella vermiformis-specific quantitative PCR (qPCR). In both supplies, highly diverse eukaryotic communities were observed, including free-living protozoa, fungi, and metazoa. Sequences of protozoa clustered with Amoebozoa (10 operational taxonomic units [OTUs]), Cercozoa (39 OTUs), Choanozoa (26 OTUs), Ciliophora (29 OTUs), Euglenozoa (13 OTUs), Myzozoa (5 OTUs), and Stramenopiles (5 OTUs). A large variety of protozoa were present in both supplies, but the estimated values for protozoan richness did not differ significantly. H. vermiformis was observed in both supplies but was not a predominant protozoan. One OTU with the highest similarity to Acanthamoeba polyphaga, an opportunistic human pathogen and a host for undesired bacteria, was observed in supply A. The high level of NOM in supply B corresponded with an elevated level of active biomass and with elevated concentrations of H. vermiformis in distributed water. Hence, the application of qPCR may be promising in elucidating the relationship between drinking water quality and the presence of specific protozoa. PMID:19465529

An introduction to food and waterborne viruses: diseases, transmission, outbreaks, detection and control

USDA-ARS?s Scientific Manuscript database

Enteric viruses are the number one cause of foodborne illness throughout the world. In addition to foods, contaminated drinking water is another major cause of enteric viral illness. Among the enteric viruses are the noroviruses, hepatitis A and E viruses, enteric adenoviruses, rotavirus, and astro...

Detection of Protozoa in Surface and Finished Waters

EPA Science Inventory

Humans are known to be the host to approximately 1500 infectious agents, out of which 66 are protozoa and 287 are helminths. Therefore, from a global perspective helminths and protozoan parasites account for approximately one fourth of the total infectious diseases of humans. A s...

Biofilms in drinking water and their role as reservoir for pathogens.

PubMed

Wingender, Jost; Flemming, Hans-Curt

2011-11-01

Most microorganisms on Earth live in various aggregates which are generally termed "biofilms". They are ubiquitous and represent the most successful form of life. They are the active agent in biofiltration and the carriers of the self-cleaning potential in soils, sediments and water. They are also common on surfaces in technical systems where they sometimes cause biofouling. In recent years it has become evident that biofilms in drinking water distribution networks can become transient or long-term habitats for hygienically relevant microorganisms. Important categories of these organisms include faecal indicator bacteria (e.g., Escherichia coli), obligate bacterial pathogens of faecal origin (e.g., Campylobacter spp.) opportunistic bacteria of environmental origin (e.g., Legionella spp., Pseudomonas aeruginosa), enteric viruses (e.g., adenoviruses, rotaviruses, noroviruses) and parasitic protozoa (e.g., Cryptosporidium parvum). These organisms can attach to preexisting biofilms, where they become integrated and survive for days to weeks or even longer, depending on the biology and ecology of the organism and the environmental conditions. There are indications that at least a part of the biofilm populations of pathogenic bacteria persists in a viable but non-culturable (VBNC) state and remains unnoticed by the methods appointed to their detection. Thus, biofilms in drinking water systems can serve as an environmental reservoir for pathogenic microorganisms and represent a potential source of water contamination, resulting in a potential health risk for humans if left unnoticed. Copyright © 2011 Elsevier GmbH. All rights reserved.

Multiplex Real-Time PCR Detection of Intestinal Protozoa in HIV-Infected Children in Malawi, Enterocytozoon Bieneusi is Common and Associated with Gastrointestinal Complaints and May Delay BMI (Nutritional Status) Recovery.

PubMed

Huibers, Minke H W; Moons, Peter; Maseko, Nelson; Gushu, Monfort B; Iwajomo, Oluwadamilola H; Heyderman, Robert S; van Hensbroek, Michael Boele; Brienen, Eric A; van Lieshout, Lisette; Calis, Job C J

2018-05-14

Intestinal protozoa are common opportunistic infections in HIV patients. Longitudinal studies on either the clinical relevance, or the effect of immune reconstitution by anti-retroviral therapy on intestinal protozoan infections are children is lacking however. This study investigates prevalence and clinical relevance of intestinal protozoa in HIV-infected Malawian children prior to and during their first year of ART. Stool samples collected at enrolment and during follow-up were tested for non-opportunistic (Giardia lamblia, Dientamoeba fragilis, Entamoeba histolytica) and opportunistic protozoa (Entroctytoon bieneusi, Encephalitozoon spp., Cryptosporidium spp and Cystoisospora belli) using multiplex real-time Polymerase Chain Reaction (PCR). Associations between infections and clinical symptoms were evaluated using univariate methods. Non-opportunistic and opportunistic protozoa were detected in 40%(14/35) and 46%(16/35) of children at baseline respectively. E. bieneusi was the most prevalent protozoa (37%, 13/35) and associated with gastrointestinal complaints(43% in positive (10/13) versus 18% (4/22) in E. bieneusi-negative children, p=0.001). Body Mass Index (BMI) recovery during 12 months of ART was more commonly delayed in E. bieneusi-positive (+0.29+SD 0.83) than E. bieneusi-negative children (+1.03+SD 1.25; p=0.05). E. bieneusi was not detected after 12 months of ART. E. bieneusi was the most prevalent opportunistic intestinal protozoa, present in over a third of study participants prior to initiation of ART. Although all children cleared E.bieneusi after 12 months of ART, E. bieneusi was associated with gastro-intestinal complaints and may delay BMI recovery. Trials to assess effect of treatment of E. bieneusi on nutritional status should be considered in HIV-infected African children.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial License 4.0 (CCBY-NC), where it is permissible to download, share, remix, transform, and buildup the work provided it is properly cited. The work cannot be used commercially without permission from the journal.

Amebiasis in four ball pythons, Python reginus.

PubMed

Kojimoto, A; Uchida, K; Horii, Y; Okumura, S; Yamaguch, R; Tateyama, S

2001-12-01

Between September 13th and November 18th in 1999, four ball pythons, Python reginus kept in the same display, showed anorexia and died one after another. At necropsy, all four snakes had severe hemorrhagic colitis. Microscopically, all snakes had severe necrotizing hemorrhagic colitis, in association with ameba-like protozoa. Some of the protozoa had macrophage-like morphology and others formed protozoal cysts with thickened walls. These protozoa were distributed throughout the wall in the large intestine. Based on the pathological findings, these snakes were infested with a member of Entamoeba sp., presumably with infection by Entamoeba invadens, the most prevalent type of reptilian amoebae.

Studies on protozoa in ancient remains - A Review

PubMed Central

Frías, Liesbeth; Leles, Daniela; Araújo, Adauto

2013-01-01

Paleoparasitological research has made important contributions to the understanding of parasite evolution and ecology. Although parasitic protozoa exhibit a worldwide distribution, recovering these organisms from an archaeological context is still exceptional and relies on the availability and distribution of evidence, the ecology of infectious diseases and adequate detection techniques. Here, we present a review of the findings related to protozoa in ancient remains, with an emphasis on their geographical distribution in the past and the methodologies used for their retrieval. The development of more sensitive detection methods has increased the number of identified parasitic species, promising interesting insights from research in the future. PMID:23440107

Not plants or animals: a brief history of the origin of Kingdoms Protozoa, Protista and Protoctista.

PubMed

Scamardella, J M

1999-12-01

In the wake of Darwin's evolutionary ideas, mid-nineteenth century naturalists realized the shortcomings of the long established two-kingdom system of organismal classification. Placement in a natural scheme of Protozoa, Protophyta, Phytozoa and Bacteria, microorganisms that exhibited plant-like and animal-like characteristics but obviously differed in organization from larger plants and animals, challenged traditional classification. The attempts of naturalists to classify these organisms outside the constraints of the plant and animal kingdoms led to concepts of additional kingdoms (Protozoa, Protista, Protoctista, etc.) to accommodate the nature of these organisms as not true plants or animals.

Diseases due to intestinale protozoa diagnosed at Le Dantec University Hospital in Dakar, Senegal, from 2011 to 2015.

PubMed

Diongue, K; Ndiaye, M; Seck, M C; Diallo, M A; Ndiaye, Y D; Badiane, A S; Ndiaye, D

2017-11-01

To identify the protozoa responsible for intestinal parasitosis diagnosed at Le Dantec University Hospital in Dakar, Senegal. The retrospective study included 2578 patients for whom stool samples were analyzed from 2011 to 2015. The sex ratio was 1.1. Patients' mean age was 28.5 years, with a range of 11 days to 91 years. Direct examination and the Ritchie technique were performed to search for parasites. In total, 317 patients had intestinal protozoa, for a prevalence of 12.3 %. Infections involved one (91%) or two parasites (9%). The most common species found alone were Entamoeba coli (51.5%), E. histolytica/E. dispar (17 %), and Giardia intestinalis (10.5%). The most common associations were E. coli with G. intestinalis (3.6 %) and with E. histolytica (2.4%). These infections affected significantly more outpatients than inpatients (65 %, p = 0.0049) and slightly more women (51.1%, p = 0.22) than men. Adults accounted for 67% of the confirmed intestinal protozoa: 39% aged 31-60 years, 28% aged 15-30, and only 7% older than 60 (p = 0.5). Most of the protozoa isolated were non-pathogenic. However, health education should be promoted in addition to the mass treatment program already begun to limit and even halt the spread of these neglected diseases.

Proton Pump Inhibitor Use Is Associated With a Reduced Risk of Infection with Intestinal Protozoa.

PubMed

Sheele, Johnathan M

2017-12-01

Proton pump inhibitors (PPIs) can kill some human protozoan parasites in cell culture better than the drug metronidazole. Clinical data showing an antiprotozoal effect for PPIs are lacking. The objective of the study is to determine if PPI use is associated with a reduced risk of having intestinal parasites. We obtained electronic medical record data for all persons who received a stool ova and parasite (O & P) examination at our tertiary care academic medical center in Cleveland, Ohio, between January 2000 and September 2014. We obtained the person's age, whether they were taking a PPI at the time of the O & P examination, and whether the pathology report indicated the presence of any parasites. χ 2 with Yates correction was used to determine if PPI use was associated with stool protozoa. Three intestinal protozoa were identified in 1199 patients taking a PPI (0.3%), and 551 intestinal parasites were identified in the 14,287 patients not taking a PPI (3.9%). There was a statistically significant lower likelihood of finding protozoa in the stool of a person taking a PPI compared with those not taking a PPI (P < .0001). Patients taking a PPI were statistically less likely to have an intestinal protozoa reported on stool O & P examination compared with those not taking a PPI. Copyright © 2017 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

A simplified experimental model for clearance of some pathogenic bacteria using common bacterivorous ciliated spp. in Tigris river

NASA Astrophysics Data System (ADS)

Ali, Talib Hassan; Saleh, Dhuha Saad

2014-03-01

Bacteria-specific uptake rates of three different protozoan taxa on a pure and mixed bacterial community was studied by means of a simplified and functionally reproducible experimental model. The bacterial species Shigella flexneri, Escherichia coli and Salmonella typhi were isolated and classified from stool samples of patients suffering from diarrhea. Paramecium caudatum, Tetrahymena pyriformis and Halteria grandinella, free living ciliate Protozoans, were isolated and identified from Tigris river water. Pure and mixed ( E. coli + S. typhi), ( E. coli + Sh. flexneri) bacterial cultures were used with each ciliate genera to evaluate the following: predator duplication rate, prey reduction rate, clearance rate and net grazing rate. We used selective lactose fermentation phenomena of enteric bacteria on MacConkey medium for the quantification of bacteria cultural characteristics. The final bacteria concentration was reduced by growing protozoa of 98-99.9 % compared to protozoa-free controls. It showed that Tetrahymena pyriformis had the highest duplication rate (4.13 time/day) in both types of cultures (pure and mixed), followed by Paramecium caudatum and Halteria grandinella, respectively. Paramecium caudatum had the highest rate of ingestion in both types of cultures (26 × 103 bacteria/organism/hr) and yielded the longest time required for 90 % bacterial reduction in a pure suspension of S. typhi (166 h). Clearance rates of pathogenic bacteria by ciliates ranged between 106 nanoliter/organism/h by P. caudatum to S. typhi and 1.92 nanoliter/organism/h seen in T. pyriformis in ( E. coli + S. typhi) mixed culture. We used aquatic experimental microcosms under controlled conditions to explore bacteria-dependent ciliate growth and examined whether these ciliates could discriminate between equally sized bacterial preys in a mixture.

Concomitant canine distemper, infectious canine hepatitis, canine parvoviral enteritis, canine infectious tracheobronchitis, and toxoplasmosis in a puppy.

PubMed

Headley, Selwyn Arlington; Alfieri, Amauri Alcindo; Fritzen, Juliana Torres Tomazi; Garcia, João Luis; Weissenböck, Herbert; da Silva, Ana Paula; Bodnar, Livia; Okano, Werner; Alfieri, Alice Fernandes

2013-01-01

The concomitant infections of Canine distemper virus (CDV), Canine adenovirus A types 1 (CAdV-1) and 2 (CAdV-2), Canine parvovirus type 2 (CPV-2), and Toxoplasma gondii are described in a 43-day-old mixed-breed puppy. Clinically, there were convulsions and blindness with spontaneous death; 14 siblings of this puppy, born to a 10-month-old dam, which was seropositive (titer: 1,024) for T. gondii, also died. Necropsy revealed unilateral corneal edema (blue eye), depletion of intestinal lymphoid tissue, non-collapsible lungs, congestion of meningeal vessels, and a pale area in the myocardium. Histopathology demonstrated necrotizing myocarditis associated with intralesional apicomplexan protozoa; necrotizing and chronic hepatitis associated with rare intranuclear inclusion bodies within hepatocytes; necrotizing bronchitis and bronchiolitis; interstitial pneumonia associated with eosinophilic intracytoplasmic inclusion bodies within epithelial cells; atrophy and fusion of intestinal villi with cryptal necrosis; and white matter demyelination of the cerebrum and cerebellum associated with intranuclear inclusion bodies within astrocytes. Polymerase chain reaction (PCR) amplified the partial fragments (bp) of the CDV N gene (290 bp), CPV-2c VP2 capsid protein gene (583 bp), and CAdV-1 (508 bp) and CAdV-2 (1,030 bp) E gene from urine and tissue samples. The PCR assays demonstrated that the apicomplexan protozoa observed within several organs contained DNA specific for T. gondii; genotyping revealed T. gondii type III. The findings support the characterization of concomitant infections of CDV, CAdV-1, CAdV-2, CPV-2, and T. gondii in this puppy. Further, seroreactivity to T. gondii of the dam in association with the systemic disease observed in the puppy described herein is suggestive of congenital toxoplasmosis.

PCR-based verification of positive rapid diagnostic tests for intestinal protozoa infections with variable test band intensity.

PubMed

Becker, Sören L; Müller, Ivan; Mertens, Pascal; Herrmann, Mathias; Zondie, Leyli; Beyleveld, Lindsey; Gerber, Markus; du Randt, Rosa; Pühse, Uwe; Walter, Cheryl; Utzinger, Jürg

2017-10-01

Stool-based rapid diagnostic tests (RDTs) for pathogenic intestinal protozoa (e.g. Cryptosporidium spp. and Giardia intestinalis) allow for prompt diagnosis and treatment in resource-constrained settings. Such RDTs can improve individual patient management and facilitate population-based screening programmes in areas without microbiological laboratories for confirmatory testing. However, RDTs are difficult to interpret in case of 'trace' results with faint test band intensities and little is known about whether such ambiguous results might indicate 'true' infections. In a longitudinal study conducted in poor neighbourhoods of Port Elizabeth, South Africa, a total of 1428 stool samples from two cohorts of schoolchildren were examined on the spot for Cryptosporidium spp. and G. intestinalis using an RDT (Crypto/Giardia DuoStrip; Coris BioConcept). Overall, 121 samples were positive for G. intestinalis and the RDT suggested presence of cryptosporidiosis in 22 samples. After a storage period of 9-10 months in cohort 1 and 2-3 months in cohort 2, samples were subjected to multiplex PCR (BD Max™ Enteric Parasite Panel, Becton Dickinson). Ninety-three percent (112/121) of RDT-positive samples for G. intestinalis were confirmed by PCR, with a correlation between RDT test band intensity and quantitative pathogen load present in the sample. For Cryptosporidium spp., all positive RDTs had faintly visible lines and these were negative on PCR. The performance of the BD Max™ PCR was nearly identical in both cohorts, despite the prolonged storage at disrupted cold chain conditions in cohort 1. The Crypto/Giardia DuoStrip warrants further validation in communities with a high incidence of diarrhoea. Copyright © 2017 Elsevier B.V. All rights reserved.

Antiparasitic Therapy

PubMed Central

Kappagoda, Shanthi; Singh, Upinder; Blackburn, Brian G.

2011-01-01

Parasitic diseases affect more than 2 billion people globally and cause substantial morbidity and mortality, particularly among the world's poorest people. This overview focuses on the treatment of the major protozoan and helminth infections in humans. Recent developments in antiparasitic therapy include the expansion of artemisinin-based therapies for malaria, new drugs for soil-transmitted helminths and intestinal protozoa, expansion of the indications for antiparasitic drug treatment in patients with Chagas disease, and the use of combination therapy for leishmaniasis and human African trypanosomiasis. PMID:21628620

Animals of the Sea: Coelenterates, Protozoa, and Sponges.

ERIC Educational Resources Information Center

Awkerman, Gary L.

These three units are designed for use with standard science curricula. These publications, relating to animals of the sea, are: Protozoa, Sponges, and Coelenterates. Included are teacher guides, student activities, and demonstrations designed to impart ocean science understanding to high school students. Objectives to be attained from the unit on…

Epidemiology of Soil-Transmitted Helminth and Intestinal Protozoan Infections in Preschool-Aged Children in the Amhara Region of Ethiopia

PubMed Central

Aiemjoy, Kristen; Gebresillasie, Sintayehu; Stoller, Nicole E.; Shiferaw, Ayalew; Tadesse, Zerihun; Chanyalew, Melsew; Aragie, Solomon; Callahan, Kelly; Keenan, Jeremy D.

2017-01-01

Intestinal parasites are important contributors to global morbidity and mortality and are the second most common cause of outpatient morbidity in Ethiopia. This cross-sectional survey describes the prevalence of soil-transmitted helminths and intestinal protozoa in preschool children 0–5 years of age in seven communities in the Amhara region of Ethiopia, and investigates associations between infection, household water and sanitation characteristics, and child growth. Stool samples were collected from children 0–5 years of age, 1 g of sample was preserved in sodium acetate–acetic acid–formalin, and examined for intestinal helminth eggs and protozoa cysts ether-concentration method. A total of 212 samples were collected from 255 randomly selected children. The prevalence of Ascaris lumbricoides, Trichuris trichiura, and hookworm were 10.8% (95% confidence interval [CI] 6.6–15.1), 1.4% (95% CI = 0–3.0), and 0% (95% CI = 0–1.7), respectively. The prevalence of the pathogenic intestinal protozoa Giardia lamblia and Entamoeba histolytica/dispar were 10.4% (95% CI = 6.2–14.6) and 3.3% (95% CI = 0.09–5.7), respectively. Children with A. lumbricoides infections had lower height-for-age z-scores compared with those without, but were not more likely to have stunting. Compared with those without G. lamblia, children with G. lamblia infections had lower weight-for-age and weight-for-height z-scores and were more than five times as likely to meet the z-score definition for wasting (prevalence ratio = 5.42, 95% CI = 2.97–9.89). This article adds to a growing body of research on child growth and intestinal parasitic infections and has implications for their treatment and prevention in preschool-aged children. PMID:28167597

Epidemiology of Soil-Transmitted Helminth and Intestinal Protozoan Infections in Preschool-Aged Children in the Amhara Region of Ethiopia.

PubMed

Aiemjoy, Kristen; Gebresillasie, Sintayehu; Stoller, Nicole E; Shiferaw, Ayalew; Tadesse, Zerihun; Chanyalew, Melsew; Aragie, Solomon; Callahan, Kelly; Keenan, Jeremy D

2017-04-01

AbstractIntestinal parasites are important contributors to global morbidity and mortality and are the second most common cause of outpatient morbidity in Ethiopia. This cross-sectional survey describes the prevalence of soil-transmitted helminths and intestinal protozoa in preschool children 0-5 years of age in seven communities in the Amhara region of Ethiopia, and investigates associations between infection, household water and sanitation characteristics, and child growth. Stool samples were collected from children 0-5 years of age, 1 g of sample was preserved in sodium acetate-acetic acid-formalin, and examined for intestinal helminth eggs and protozoa cysts ether-concentration method. A total of 212 samples were collected from 255 randomly selected children. The prevalence of Ascaris lumbricoides , Trichuris trichiura , and hookworm were 10.8% (95% confidence interval [CI] 6.6-15.1), 1.4% (95% CI = 0-3.0), and 0% (95% CI = 0-1.7), respectively. The prevalence of the pathogenic intestinal protozoa Giardia lamblia and Entamoeba histolytica / dispar were 10.4% (95% CI = 6.2-14.6) and 3.3% (95% CI = 0.09-5.7), respectively. Children with A. lumbricoides infections had lower height-for-age z -scores compared with those without, but were not more likely to have stunting. Compared with those without G. lamblia , children with G. lamblia infections had lower weight-for-age and weight-for-height z -scores and were more than five times as likely to meet the z -score definition for wasting (prevalence ratio = 5.42, 95% CI = 2.97-9.89). This article adds to a growing body of research on child growth and intestinal parasitic infections and has implications for their treatment and prevention in preschool-aged children.

Comparison of fermentation of diets of variable composition and microbial populations in the rumen of sheep and Rusitec fermenters. II. Protozoa population and diversity of bacterial communities.

PubMed

Martínez, M E; Ranilla, M J; Tejido, M L; Saro, C; Carro, M D

2010-08-01

Four ruminally and duodenally cannulated sheep and 8 Rusitec fermenters were used to determine the effects of dietary characteristics on microbial populations and bacterial diversity. The purpose of the study was to assess how closely fermenters can mimic the differences between diets found in vivo. The 4 experimental diets contained forage to concentrate (F:C) ratios of 70:30 (high forage; HF) or 30:70 (high concentrate; HC) with either alfalfa hay (A) or grass hay (G) as the forage. Total bacterial numbers were greater in the rumen of sheep fed HF diets compared with those fed HC diets, whereas the opposite was found in fermenters. The numbers of cellulolytic bacteria were not affected by F:C ratio in any fermentation system, but cellulolytic numbers were 2.7 and 1.8 times greater in sheep than in fermenters for HF and HC diets, respectively. Neither total bacterial nor cellulolytic numbers were affected by the type of forage in sheep or fermenters. Decreasing F:C ratio increased total protozoa and Entodiniae numbers in sheep by about 29 and 25%, respectively, but it had no effect in fermenters. Isotrichidae and Ophryoscolecinae numbers in sheep were not affected by changing F:C ratio, but both disappeared completely from fermenters fed HC diets. Total protozoa and Entodiniae numbers were greater in sheep fed A diets than in those fed G diets, whereas the opposite was found in fermenters. Results indicate that under the conditions of the present study, protozoa population in Rusitec fermenters was not representative of that in the rumen of sheep fed the same diets. In addition, protozoa numbers in fermenters were 121 and 226 times lower than those in the sheep rumen for HF and HC diets, respectively. The automated ribosomal intergenic spacer analysis of the 16S ribosomal DNA was used to analyze the diversity of liquid- and solid-associated bacteria in both systems. A total of 170 peaks were detected in the automated ribosomal intergenic spacer analysis electropherograms of bacterial pellets across the full set of 64 samples, from which 160 were detected in at least 1 individual from each system (sheep or fermenter). Diversity of liquid-associated bacterial pellets was greater with G diets in fermenters but seemed to be unaffected by diet in sheep. Bacterial diversity in solid-associated bacteria pellets was greater for G diets compared with A diets in sheep and fermenters. Different conditions in the fermenters compared with sheep rumen might have caused a selection of some bacterial strains. Copyright (c) 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

21 CFR 520.2345c - Tetracycline boluses.

Code of Federal Regulations, 2010 CFR

2010-04-01

... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia caused by Pasteurella spp... tetracycline, bacterial enteritis caused by E. coli, and salmonella organisms susceptible to tetracycline. (ii...

21 CFR 520.2345c - Tetracycline boluses.

Code of Federal Regulations, 2011 CFR

2011-04-01

... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia caused by Pasteurella spp... tetracycline, bacterial enteritis caused by E. coli, and salmonella organisms susceptible to tetracycline. (ii...

World Health Organization Estimates of the Global and Regional Disease Burden of 11 Foodborne Parasitic Diseases, 2010: A Data Synthesis

PubMed Central

Torgerson, Paul R.; Devleesschauwer, Brecht; Praet, Nicolas; Speybroeck, Niko; Willingham, Arve Lee; Kasuga, Fumiko; Rokni, Mohammad B.; Zhou, Xiao-Nong; Fèvre, Eric M.; Sripa, Banchob; Gargouri, Neyla; Fürst, Thomas; Budke, Christine M.; Carabin, Hélène; Kirk, Martyn D.; Angulo, Frederick J.; Havelaar, Arie; de Silva, Nilanthi

2015-01-01

Background Foodborne diseases are globally important, resulting in considerable morbidity and mortality. Parasitic diseases often result in high burdens of disease in low and middle income countries and are frequently transmitted to humans via contaminated food. This study presents the first estimates of the global and regional human disease burden of 10 helminth diseases and toxoplasmosis that may be attributed to contaminated food. Methods and Findings Data were abstracted from 16 systematic reviews or similar studies published between 2010 and 2015; from 5 disease data bases accessed in 2015; and from 79 reports, 73 of which have been published since 2000, 4 published between 1995 and 2000 and 2 published in 1986 and 1981. These included reports from national surveillance systems, journal articles, and national estimates of foodborne diseases. These data were used to estimate the number of infections, sequelae, deaths, and Disability Adjusted Life Years (DALYs), by age and region for 2010. These parasitic diseases, resulted in 48.4 million cases (95% Uncertainty intervals [UI] of 43.4–79.0 million) and 59,724 (95% UI 48,017–83,616) deaths annually resulting in 8.78 million (95% UI 7.62–12.51 million) DALYs. We estimated that 48% (95% UI 38%-56%) of cases of these parasitic diseases were foodborne, resulting in 76% (95% UI 65%-81%) of the DALYs attributable to these diseases. Overall, foodborne parasitic disease, excluding enteric protozoa, caused an estimated 23.2 million (95% UI 18.2–38.1 million) cases and 45,927 (95% UI 34,763–59,933) deaths annually resulting in an estimated 6.64 million (95% UI 5.61–8.41 million) DALYs. Foodborne Ascaris infection (12.3 million cases, 95% UI 8.29–22.0 million) and foodborne toxoplasmosis (10.3 million cases, 95% UI 7.40–14.9 million) were the most common foodborne parasitic diseases. Human cysticercosis with 2.78 million DALYs (95% UI 2.14–3.61 million), foodborne trematodosis with 2.02 million DALYs (95% UI 1.65–2.48 million) and foodborne toxoplasmosis with 825,000 DALYs (95% UI 561,000–1.26 million) resulted in the highest burdens in terms of DALYs, mainly due to years lived with disability. Foodborne enteric protozoa, reported elsewhere, resulted in an additional 67.2 million illnesses or 492,000 DALYs. Major limitations of our study include often substantial data gaps that had to be filled by imputation and suffer from the uncertainties that surround such models. Due to resource limitations it was also not possible to consider all potentially foodborne parasites (for example Trypanosoma cruzi). Conclusions Parasites are frequently transmitted to humans through contaminated food. These estimates represent an important step forward in understanding the impact of foodborne diseases globally and regionally. The disease burden due to most foodborne parasites is highly focal and results in significant morbidity and mortality among vulnerable populations. PMID:26633705

Adherence of Trichomonas vaginalis to cell culture monolayers.

PubMed

Martinotti, M G; Martinetto, P; Savoia, D

1986-06-01

The in vitro adherence to WISH cells of a pathogenic Trichomonas vaginalis strain was studied with a method utilizing thymidine-labeled protozoa. A marked dose-related adherence was observed. Glutaraldehyde fixed trichomonads were not adherent. The presence of fetal calf serum during the assay did not influence attachment. Concanavalin A inhibited adherence of protozoa. Complete or partial inhibition of adherence was achieved by preincubating WISH cells with Lactobacillus fermentum or Streptococcus agalactiae. Finally, pretreatment of cells with alpha-estradiol, beta-estradiol, progesterone and estrone influenced attachment of protozoa, whereas estriol was ineffective. These results suggest that adherence of Trichomonas vaginalis is dependent on different factors, whose manipulation may have clinical relevance in preventing recurrence of trichomonad vaginitis.

Neglected waterborne parasitic protozoa and their detection in water.

PubMed

Plutzer, Judit; Karanis, Panagiotis

2016-09-15

Outbreak incidents raise the question of whether the less frequent aetiological agents of outbreaks are really less frequent in water. Alternatively, waterborne transmission could be relevant, but the lack of attention and rapid, sensitive methods to recover and detect the exogenous stages in water may keep them under-recognized. High quality information on the prevalence and detection of less frequent waterborne protozoa, such as Cyclospora cayetanensis, Toxoplasma gondii, Isospora belli, Balantidium coli, Blastocystis hominis, Entamoeba histolytica and other free-living amoebae (FLA), are not available. This present paper discusses the detection tools applied for the water surveillance of the neglected waterborne protozoa mentioned above and provides future perspectives. Copyright © 2016 Elsevier Ltd. All rights reserved.

21 CFR 520.90f - Ampicillin trihydrate boluses.

Code of Federal Regulations, 2012 CFR

2012-04-01

... enteritis (colibacillosis) caused by E. coli. (ii) Limitations. Treated calves must not be slaughtered for... coli, bacterial enteritis caused by Salmonella spp., and bacterial pneumonia caused by Pasteurella spp...

21 CFR 520.90f - Ampicillin trihydrate boluses.

Code of Federal Regulations, 2010 CFR

2010-04-01

... enteritis (colibacillosis) caused by E. coli. (ii) Limitations. Treated calves must not be slaughtered for... coli, bacterial enteritis caused by Salmonella spp., and bacterial pneumonia caused by Pasteurella spp...

21 CFR 520.90f - Ampicillin trihydrate boluses.

Code of Federal Regulations, 2011 CFR

2011-04-01

... enteritis (colibacillosis) caused by E. coli. (ii) Limitations. Treated calves must not be slaughtered for... coli, bacterial enteritis caused by Salmonella spp., and bacterial pneumonia caused by Pasteurella spp...

PROTOZOA IN SUBSURFACE SEDIMENTS FROM SITE CONTAMI- NATED WITH AVIATION GASOLINE OR JET FUEL

EPA Science Inventory

Numbers of protozoa in the subsurface of aviation gasoline and jet fuel spill areas at a Coast Guard base at Traverse City, Mich., were determined. Boreholes were drilled in an uncontaminated location, in contaminated but untreated parts of the fuel plumes, and in the aviation ga...

Detection of zoonotic protozoa Toxoplasma gondii and Sarcocystis suihominis in wild boars from Spain

USDA-ARS?s Scientific Manuscript database

Food safety regulations require the control of presence of protozoa in meats destined for human consumption. Wild boar (Sus scrofa) meat may constitute a source of zoonoses. A 23.8% (688/2881) seroprevalence of anti-Toxoplasma gondii antibodies, and 72.2% (662/910) Sarcocystis sarcocysts prevalence ...

Explore the World Using Protozoa.

ERIC Educational Resources Information Center

Anderson, O. Roger, Ed.; Druger, Marvin, Ed.

This book is a joint publication of the National Science Teachers Association (NSTA) and the Society of Protozoologists and is the result of efforts to find a way in which protozoa research can be used to teach biology. This program puts cutting edge science into the hands of science teachers and enables students to experience a variety of…

Density and diversity of protozoa in some arid Australian soils.

PubMed

Robinson, Bret S; Bamforth, Stuart S; Dobson, Philip J

2002-01-01

This is the first extensive study of soil protozoa of arid lands. Twenty-six samples from litters, soils, termitaria, and a cyanobacterial crust, collected from central and south Australian arid lands, were analyzed for numbers and species of gymnamoebae, ciliates, and testacea. Amoebae ranged from 1,000-5,000/g of material, and were two orders of magnitude more abundant than ciliates. Both groups increased in abundance and species richness from bare soils through spinifex to mulga to chenopod vegetations. Testacea ranged 900-5,000/g with similar species richness throughout vegetations, but reached 11,900/g with a doubling of species in a refugium in Kings Canyon. The most prevalent species of amoebae, ciliates, and testacea were taxa associated with ephemeral and disturbed habitats (r-selection). The cyanobacterial crust might be considered a micro-refugium because it contained a number of non-encysting protozoa, including Thecamoeba sp. and Nassula picta, feeding on cyanobacterial filaments. The numbers and species richness of protozoa under shrubs were greater than in bare soils, supporting the resource island hypothesis that desert plants create soil heterogeneity by localizing soil fertility under their canopies.

The effect of acid drinking water on rumen protozoa in the blesbok (Damaliscus dorcas phillipsi).

PubMed

Booyse, D G; Dehority, B A; Myburgh, J G

2015-12-07

Rumen contents were collected from ten adult female blesbok, five from a mine area with only acid drinking water available and five from a control group consuming normal, non-polluted drinking water. The mean concentration of total protozoa in the normal water group was almost double that in the acid drinking water group, 24.9 x 10(3) versus 14.7 x 10(3). Percent of Entodinium was higher and Diplodinium lower in those animals drinking the acid water. The number of different protozoa species present in animals from both locations was fairly similar. Diplodinium bubalidis, Ostracodinium gracile and Diplodinium consors were present in the highest percentage in the normal water group, 18.8, 18.4 and 17.7 %, respectively. The same three species, plus Entodinium dubardi, were also highest in the acid water group, O. gracile, 21.3 %; D. consors, 12.6 %; E. dubardi, 11.4 % and D. bubalidis, 10.3 %. Seventeen species of protozoa found in this study were a new host record for the blesbok, bringing the total number of species reported from the blesbok to 29.

Studies on the in vitro cultivation of ciliate protozoa from the kangaroo forestomach.

PubMed

Dehority, Burk A; Wright, André-Denis G

2014-08-01

The methods used for culturing rumen protozoa were found to be unsatisfactory for growth of ciliate protozoa from the kangaroo forestomach. Based on published measurements of physical parameters in the marsupial forestomach, several modifications were incorporated into the procedure, i.e., an increase in % hydrogen in the gas phase, adjustment of initial pH of the medium to 6.9-7.0 range, feed only forage as a substrate and incubate at a lower temperature (33-36 °C). Only incubation at the lower temperature increased survival time of the kangaroo protozoa. Two species of Bitricha were still viable after 28 d in culture. Cultures had to be terminated at that time. One of the species differed considerably in size and shape from previously described species and based on 18S rRNA data, may represent a new species of Bitricha. The second species, present in low numbers was identified as Bitricha oblata. In a separate trial, Macropodinium yalanbense survived for 11 d, at which time these cultures also had to be terminated. Copyright © 2014 Elsevier GmbH. All rights reserved.

A legacy of low-impact logging does not elevate prevalence of potentially pathogenic protozoa in free-ranging gorillas and chimpanzees in the Republic of Congo: logging and parasitism in African apes.

PubMed

Gillespie, Thomas R; Morgan, David; Deutsch, J Charlie; Kuhlenschmidt, Mark S; Salzer, Johanna S; Cameron, Kenneth; Reed, Trish; Sanz, Crickette

2009-12-01

Many studies have examined the long-term effects of selective logging on the abundance and diversity of free-ranging primates. Logging is known to reduce the abundance of some primate species through associated hunting and the loss of food trees for frugivores; however, the potential role of pathogens in such primate population declines is largely unexplored. Selective logging results in a suite of alterations in host ecology and forest structure that may alter pathogen dynamics in resident wildlife populations. In addition, environmental pollution with human fecal material may present a risk for wildlife infections with zoonotic protozoa, such as Cryptosporidium and Giardia. To better understand this interplay, we compared patterns of infection with these potentially pathogenic protozoa in sympatric western lowland gorillas (Gorilla gorilla gorilla) and chimpanzees (Pan troglodytes troglodytes) in the undisturbed Goualougo Triangle of Nouabalé-Ndoki National Park and the adjacent previously logged Kabo Concession in northern Republic of Congo. No Cryptosporidium infections were detected in any of the apes examined and prevalence of infection with Giardia was low (3.73% overall) and did not differ between logged and undisturbed forest for chimpanzees or gorillas. These results provide a baseline for prevalence of these protozoa in forest-dwelling African apes and suggest that low-intensity logging may not result in long-term elevated prevalence of potentially pathogenic protozoa.

A Legacy of Low-Impact Logging does not Elevate Prevalence of Potentially Pathogenic Protozoa in Free-Ranging Gorillas and Chimpanzees in the Republic of Congo: Logging and Parasitism in African Apes

PubMed Central

Morgan, David; Deutsch, J. Charlie; Kuhlenschmidt, Mark S.; Salzer, Johanna S.; Cameron, Kenneth; Reed, Trish; Sanz, Crickette

2010-01-01

Many studies have examined the long-term effects of selective logging on the abundance and diversity of free-ranging primates. Logging is known to reduce the abundance of some primate species through associated hunting and the loss of food trees for frugivores; however, the potential role of pathogens in such primate population declines is largely unexplored. Selective logging results in a suite of alterations in host ecology and forest structure that may alter pathogen dynamics in resident wildlife populations. In addition, environmental pollution with human fecal material may present a risk for wildlife infections with zoonotic protozoa, such as Cryptosporidium and Giardia. To better understand this interplay, we compared patterns of infection with these potentially pathogenic protozoa in sympatric western lowland gorillas (Gorilla gorilla gorilla) and chimpanzees (Pan troglodytes troglodytes) in the undisturbed Goualougo Triangle of Nouabalé-Ndoki National Park and the adjacent previously logged Kabo Concession in northern Republic of Congo. No Cryptosporidium infections were detected in any of the apes examined and prevalence of infection with Giardia was low (3.73% overall) and did not differ between logged and undisturbed forest for chimpanzees or gorillas. These results provide a baseline for prevalence of these protozoa in forest-dwelling African apes and suggest that low-intensity logging may not result in long-term elevated prevalence of potentially pathogenic protozoa. PMID:20238141

Phlebotomine sand fly–borne pathogens in the Mediterranean Basin: Human leishmaniasis and phlebovirus infections

PubMed Central

Moriconi, Martina; Rugna, Gianluca; Calzolari, Mattia; Bellini, Romeo; Albieri, Alessandro; Angelini, Paola; Cagarelli, Roberto; Landini, Maria P.

2017-01-01

Pathogens transmitted to humans by phlebotomine sand flies are neglected, as they cause infectious diseases that are not on the priority list of national and international public health systems. However, the infections caused by protozoa of the Leishmania genus and viruses belonging to the Phlebovirus genus (family Phenuiviridae)—the most significant group of viruses transmitted by sand flies—have a relevant role for human pathology. These infections are emerging in the Mediterranean region and will likely spread in forthcoming decades, posing a complex threat to human health. Four species and 2 hybrid strains of Leishmania are pathogenic for humans in the Mediterranean Basin, with an estimated annual incidence of 239,500–393,600 cases of cutaneous leishmaniasis and 1,200–2,000 cases of visceral leishmaniasis. Among the phleboviruses, Toscana virus can cause neuroinvasive infections, while other phleboviruses are responsible for a typical “3-day fever”; the actual incidence of Phlebovirus infections in the Mediterranean area is unknown, although at least 250 million people are exposed. Here, we reviewed the current literature on epidemiology of sand fly–borne infections in the Mediterranean Basin, with a focus on humans. Our analysis indicates the need for increased public health activities directed to determine the disease burden of these infections as well as to improve their surveillance. Among the emerging challenges concerning sand fly–borne pathogens, the relationships between sand fly–borne protozoa and viruses should be considered in future studies, including epidemiological links between Leishmania and phleboviruses as well as the conditional capacity for these pathogens to be involved in interactions that may evolve towards increased virulence. PMID:28796786

Metavirome Sequencing of the Termite Gut Reveals the Presence of an Unexplored Bacteriophage Community

PubMed Central

Tikhe, Chinmay V.; Husseneder, Claudia

2018-01-01

The Formosan subterranean termite; Coptotermes formosanus is nutritionally dependent on the complex and diverse community of bacteria and protozoa in their gut. Although, there have been many studies to decipher the taxonomic and functional diversity of bacterial communities in the guts of termites, their bacteriophages remain unstudied. We sequenced the metavirome of the guts of Formosan subterranean termite workers to study the diversity of bacteriophages and other associated viruses. Results showed that the termites harbor a virome in their gut comprised of varied and previously unknown bacteriophages. Between 87–90% of the predicted dsDNA virus genes by Metavir showed similarity to the tailed bacteriophages (Caudovirales). Many predicted genes from the virome matched to bacterial prophage regions. These data are suggestive of a virome dominated by temperate bacteriophages. We predicted the genomes of seven novel Caudovirales bacteriophages from the termite gut. Three of these predicted bacteriophage genomes were found in high proportions in all the three termite colonies tested. Two bacteriophages are predicted to infect endosymbiotic bacteria of the gut protozoa. The presence of these putative bacteriophages infecting endosymbionts of the gut protozoa, suggests a quadripartite relationship between the termites their symbiotic protozoa, endosymbiotic bacteria of the protozoa and their bacteriophages. Other than Caudovirales, ss-DNA virus related genes were also present in the termite gut. We predicted the genomes of 12 novel Microviridae phages from the termite gut and seven of those possibly represent a new proposed subfamily. Circovirus like genomes were also assembled from the termite gut at lower relative abundance. We predicted 10 novel circovirus genomes in this study. Whether these circoviruses infect the termites remains elusive at the moment. The functional and taxonomical annotations suggest that the termites may harbor a core virome comprised of the bacteriophages infecting endosymbionts of the gut protozoa. PMID:29354098

Chemotaxis toward carbohydrates and peptides by mixed ruminal protozoa when fed, fasted, or incubated with polyunsaturated fatty acids.

PubMed

Diaz, H L; Karnati, S K R; Lyons, M A; Dehority, B A; Firkins, J L

2014-01-01

In contrast to the well-characterized chemotaxis and migratory behavior between the dorsal and ventral locations of the rumen by isotrichids, we hypothesized that chemotaxis toward soluble nutrients maintains entodiniomorphid protozoa in the particulate fraction. The objectives of these experiments were to compare the dose-responsive chemotaxis (1) toward different glucose concentrations when ruminal samples were harvested from fed versus fasted cows; (2) toward increasing concentrations of glucose compared with xylose when protozoa were harvested from a fed cow; (3) toward peptides of bacterial, protozoal, and soy origin; and (4) toward glucose when mixed ruminal protozoa were previously incubated for 0, 3, or 6h in the presence of emulsified polyunsaturated fatty acids (PUFA; Liposyn II, Hospira, Lake Forest, IL). In experiment 1, isotrichid protozoa decreased chemotaxis toward increasing glucose concentration when cows were fasted. Entodiniomorphids exhibited chemotaxis to similar concentrations of glucose as did isotrichids, but to a lesser magnitude of response. In experiment 2, xylose was chemotactic to both groups. Xylose might draw fibrolytic entodiniomorphid protozoa toward newly ingested feed. In contrast, even though isotrichids should not use xylose as an energy source, they were highly chemoattracted to xylose. In experiment 3, entodiniomorphids were not selectively chemoattracted toward bacterial or protozoal peptides compared with soy peptides. In experiment 4, despite isotrichid populations decreasing in abundance with increasing time of incubation in PUFA, chemotaxis to glucose remained unchanged. In contrast, entodiniomorphids recovered chemotaxis to glucose with increased time of PUFA incubation. Current results support isotrichid chemotaxis to sugars but also our hypothesis that a more moderate chemotaxis toward glucose and peptides explains how they swim in the fluid but pass from the rumen with the potentially digestible fraction of particulates. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Attenuation of Leishmania infantum chagasi Metacyclic Promastigotes by Sterol Depletion

PubMed Central

Gaur Dixit, Upasna; Barker, Jason H.; Teesch, Lynn M.; Love-Homan, Laurie; Donelson, John E.; Wilson, Mary E.

2013-01-01

The infectious metacyclic promastigotes of Leishmania protozoa establish infection in a mammalian host after they are deposited into the dermis by a sand fly vector. Several Leishmania virulence factors promote infection, including the glycosylphosphatidylinositol membrane-anchored major surface protease (MSP). Metacyclic Leishmania infantum chagasi promastigotes were treated with methyl-beta-cyclodextrin (MβCD), a sterol-chelating reagent, causing a 3-fold reduction in total cellular sterols as well as enhancing MSP release without affecting parasite viability in vitro. MβCD-treated promastigotes were more susceptible to complement-mediated lysis than untreated controls and reduced the parasite load 3-fold when inoculated into BALB/c mice. Paradoxically, MβCD-treated promastigotes caused a higher initial in vitro infection rate in human or murine macrophages than untreated controls, although their intracellular multiplication was hindered upon infection establishment. There was a corresponding larger amount of covalently bound C3b than iC3b on the parasite surfaces of MβCD-treated promastigotes exposed to healthy human serum in vitro, as well as loss of MSP, a protease that enhances C3b cleavage to iC3b. Mass spectrometry showed that MβCD promotes the release of proteins into the extracellular medium, including both MSP and MSP-like protein (MLP), from virulent metacyclic promastigotes. These data support the hypothesis that plasma membrane sterols are important for the virulence of Leishmania protozoa at least in part through retention of membrane virulence proteins. PMID:23630964

Ability of select probiotics to reduce enteric Campylobacter colonization in broiler chickens

USDA-ARS?s Scientific Manuscript database

Campylobacter is the leading cause of foodborne enteritis worldwide and is primarily caused by consumption/mishandling of contaminated poultry. Probiotic use in poultry has been an effective strategy in reducing many enteric pathogens, but has not demonstrated consistent reduction against Campylobac...

New Disinfection Agents for Water

DTIC Science & Technology

1984-10-01

oo20 7 Effect of Agent I and HTII on Viability of Entamoeba invadens ..... ................ o...type I and rotavirus), protozoa ( Entamoeba invadens and Giardia lamblia), and fungi (Rhodotorula rubra and Candida albicans). Variables in the study...sufficiently long contact time. PROTOZOA STUDIES The IP-1 strain of Entamoeba invadens and the Portland strain of Giardia lamblia were grown in 15 mL

Characteristics of Factors of Protozoa Blastocystis hominis Persistence.

PubMed

Potaturkina-Nesterova, N I; Il'ina, N A; Bugero, N V; Nesterov, A S

2016-10-01

Persistence activity manifested in the expression of anti-lysozyme, anti-lactoferrin, and antihistone factors promoting inactivation of natural anti-infection resistance factors in the body was revealed in Blastocystis hominis protozoa. Activities of these factors were ranged. The frequency of these factors in clinical isolates of blastocyst decreased in the following order: anti-lactoferrin activity (84.5±3.7%)→anti-lysozyme activity (64.8±5.7%)→anti-histone activity (48.1±2.3%). In healthy humans, the corresponding parameters were 7.3±1.3, 5.3±0.9, and 3.3±0.4%, respectively (p<0.05). It was shown that the studied activities in highly virulent blastocysts were higher than in groups of medium-, low-, and avirulent protozoa.

Morphological, morphometric, and molecular characterization of Hepatozoon spp. (Apicomplexa, Hepatozoidae) from naturally infected Caudisona durissa terrifica (Serpentes, Viperidae).

PubMed

Moço, Tatiana Cristina; da Silva, Reinaldo José; Madeira, Newton Goulart; Dos Santos Paduan, Karina; Rubini, Adriano Stefani; Leal, Denise Dutra Menezes; O'Dwyer, Lucia Helena

2012-04-01

Hepatozoon spp. are the most frequent intracellular protozoa in snakes. Considering the variety of parasites infecting specimens of Caudisona durissa terrifica and the divergent data in literature where only two species, Hepatozoon romani and Hepatozoon capsulata, are described, the aim of this study was to morphologically, morphometrically, and molecularly characterize Hepatozoon spp. from some naturally infected specimens of C. durissa terrifica, and observe changes caused by these protozoa in parasitized erythrocytes. Four snakes were examined. Two of them had two morphological distinct gamonts, while the other two had only one type of gamont. The six distinct gamonts were provisionally named gamonts A, B, C, D, E, and F. Statistical analysis, however, confirmed the existence of only four parasite populations, those which were capable of inducing significant alterations in determined red blood cells variables. Attempts to infect Aedes aegypti and Culex quinquefasciatus mosquitoes were done for each snake specimen. Some mosquitoes became infected and oocysts were recovered and measured. The detection of Hepatozoon DNA was obtained with success but the molecular characterization was unable to differentiate species of the samples, with respect to the fragment studied.

Monitoring of Noxious Protozoa for Management of Natural Water Resources.

PubMed

Bahk, Young Yil; Cho, Pyo Yun; Ahn, Sung Kyu; Park, Sangjung; Jheong, Won Hwa; Park, Yun-Kyu; Shin, Ho-Joon; Lee, Sang-Seob; Rhee, Okjae; Kim, Tong-Soo

2018-04-01

Waterborne parasitic protozoa, particularly Giardia lamblia and Cryptosporidium spp., are common causes of diarrhea and gastroenteritis worldwide. The most frequently identified source of infestation is water, and exposure involves either drinking water or recreation in swimming pools or natural bodies of water. In practice, studies on Cryptosporidium oocysts and Giardia cysts in surface water are challenging owing to the low concentrations of these microorganisms because of dilution. In this study, a 3-year monitoring of Cryptosporidium parvum, Giardia lamblia , and Naegleria fowleri was conducted from August 2014 to June 2016 at 5 surface water sites including 2 lakes, 1 river, and 2 water intake plants. A total of 50 water samples of 40 L were examined. Cryptosporidium oocysts were detected in 22% of samples and Giardia cysts in 32%. Water at the 5 sampling sites was all contaminated with Cryptosporidium oocysts (0-36/L), Giardia cysts (0-39/L), or both. The geometric mean concentrations of Cryptosporidium and Giardia were 1.14 oocysts/L and 4.62 cysts/L, respectively. Thus, effective monitoring plans must take into account the spatial and temporal parameters of contamination because they affect the prevalence and distribution of these protozoan cysts in local water resources.

Sarcocystid organisms found in bile from a dog with acute hepatitis: a case report and review of intestinal and hepatobiliary Sarcocystidae infections in dogs and cats.

PubMed

Irvine, Katherine L; Walker, Julie M; Friedrichs, Kristen R

2016-03-01

Sarcocystidae is a family of coccidian protozoa from the phylum Apicomplexa that includes Toxoplasma, Neospora, Sarcocystis, Hammondia, and Besnoitia spp. All species undergo a 2-host sexual and asexual cycle. In the definitive host, replication is enteroepithelial, and infection is typically asymptomatic or less commonly causes mild diarrhea. Clinical disease is most frequently observed in the intermediate host, often as an aberrant infection, and is mostly associated with neurologic, muscular, or hepatic inflammation. Here, we review the literature regarding intestinal Sarcocystidae infections in dogs and cats, with emphasis on the life cycle stages and the available diagnostic assays and their limitations. We also report the diagnostic findings for an 11-year-old dog with acute neutrophilic hepatitis, biliary protozoa, and negative biliary culture. Although Toxoplasma and Neospora IgG titers were both high, PCR for these 2 organisms was negative for bile. The organisms were identified by 18S rDNA PCR as most consistent with Hammondia, either H heydorni or H triffittae. This is the first report of presumed Hammondia organisms being found in canine bile. © 2016 American Society for Veterinary Clinical Pathology.

Four phage endolysins that are lytic for clostridium perfringens

USDA-ARS?s Scientific Manuscript database

Clostridium perfringens is a bacterial pathogen and the cause of necrotic enteritis in poultry, and a source of food poisoning and gas gangrene in people. C. perfringens can also cause mild to severe enteritis in pigs. In the EU, the occurrence of C. perfringens-associated necrotic enteritis in pou...

Molecular epidemiology of Giardia and Cryptosporidium infections.

PubMed

Thompson, R C A; Ash, A

2016-06-01

Giardia and Cryptosporidium are ubiquitous enteric protozoan pathogens of vertebrates. Although recognised as the aetiological agents of disease in humans and domestic animals for many years, fundamental questions concerning their ecology have been unresolved. Molecular tools have helped to better understand their genetic diversity and in so doing have helped to resolve questions about their transmission patterns and associated impacts on public health. However, the value of molecular tools is often complicated by questions concerning their applications, interpretation of results and terminology. Taxonomic issues have, until recently, made it difficult to determine the epidemiology of infections with both Giardia and Cryptosporidium. Similarly, improved understanding of their respective phylogenetic relationships has helped to resolve questions about zoonotic potential and distribution in wildlife. In the case of Cryptosporidium, imaging technologies have complemented phylogenetic studies in demonstrating the parasite's affinities with gregarine protozoa and have further supported its extracellular developmental capability and potential role as an environmental pathogen. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Development of a novel method for simultaneous concentration of viruses and protozoa from a single water sample.

PubMed

Haramoto, Eiji; Katayama, Hiroyuki; Asami, Mari; Akiba, Michihiro

2012-06-01

A novel method, electronegative membrane-vortex (EMV) method, was developed for simultaneous concentration of viruses and protozoa from a single water sample. Viruses and protozoa in a water sample were mixed with a cation solution and adsorbed on an electronegative membrane. Concentrated virus and protozoa samples were obtained as supernatant and pellet fractions, respectively, by vigorous vortex mixing of the membrane and centrifugation of the eluted material. The highest recovery efficiencies of model microbes from river water and tap water by this EMV method were obtained using a mixed cellulose ester membrane with a pore size of 0.45 μm (Millipore) as the electronegative membrane and MgCl(2) as the cation solution. The recovery was 27.7-86.5% for poliovirus, 25.7-68.3% for coliphage Qβ, 28.0-60.0% for Cryptosporidium oocysts, and 35.0-53.0% for Giardia cysts. The EMV method detected successfully indigenous viruses and protozoa in wastewater and river water samples from the Kofu basin, Japan, showing an overall positive rate of 100% (43/43) for human adenovirus, 79% (34/43) for norovirus GI, 65% (28/43) for norovirus GII, 23% (10/43) for Cryptosporidium oocysts, and 60% (26/43) for Giardia cysts. By direct DNA sequencing, a total of four genotypes (AI, AII, B, and G) of Giardia intestinalis were identified in the water samples, indicating that the river water was contaminated with feces from various mammals, including humans. Copyright © 2012 Elsevier B.V. All rights reserved.

Detection of protozoa in water samples by formalin/ether concentration method.

PubMed

Lora-Suarez, Fabiana; Rivera, Raul; Triviño-Valencia, Jessica; Gomez-Marin, Jorge E

2016-09-01

Methods to detect protozoa in water samples are expensive and laborious. We evaluated the formalin/ether concentration method to detect Giardia sp., Cryptosporidium sp. and Toxoplasma in water. In order to test the properties of the method, we spiked water samples with different amounts of each protozoa (0, 10 and 50 cysts or oocysts) in a volume of 10 L of water. Immunofluorescence assay was used for detection of Giardia and Cryptosporidium. Toxoplasma oocysts were identified by morphology. The mean percent of recovery in 10 repetitions of the entire method, in 10 samples spiked with ten parasites and read by three different observers, were for Cryptosporidium 71.3 ± 12, for Giardia 63 ± 10 and for Toxoplasma 91.6 ± 9 and the relative standard deviation of the method was of 17.5, 17.2 and 9.8, respectively. Intraobserver variation as measured by intraclass correlation coefficient, was fair for Toxoplasma, moderate for Cryptosporidium and almost perfect for Giardia. The method was then applied in 77 samples of raw and drinkable water in three different plant of water treatment. Cryptosporidium was found in 28 of 77 samples (36%) and Giardia in 31 of 77 samples (40%). Theses results identified significant differences in treatment process to reduce the presence of Giardia and Cryptosporidium. In conclusion, the formalin ether method to concentrate protozoa in water is a new alternative for low resources countries, where is urgently need to monitor and follow the presence of theses protozoa in drinkable water. Copyright © 2016 Elsevier Ltd. All rights reserved.

Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Gulf of Mexico). WHITE SHRIMP.

DTIC Science & Technology

1984-09-01

white and coastal waters, shrimp has increased greatly over the years. Before 1902, less than 12 mil- lion lb of shrimp were landed annually Disease and...that viruses, bac- shrimp) averaged 7.8 million lb in 7 teria, fungi, protozoa, helminths, and Texas and 40.5 million lb in Louisi- nematodes cause...Japanese (Kuruma) shrimp food. In 1955, an estimated 59 mil- per 10 to 15 kg of feed at optimum - lion bait shrimp were taken by the 25°C temperature

Effects of feeding lauric acid on ruminal protozoa numbers, fermentation, and digestion and on milk production in dairy cows

USDA-ARS?s Scientific Manuscript database

The objectives of this study were: (1) to determine the level of lauric acid (LA) addition to the diet necessary to effectively suppress ruminal protozoa (RP) to the extent observed when a single dose was given directly into the rumen; (2) to assess its effects on production and ruminal metabolism; ...

Alternative mounting media for preservation of some protozoa.

PubMed

Criado-Fornelio, A; Heredero-Bermejo, I; Pérez-Serrano, J

2014-10-01

Protozoa resistant stages are disintegrated when mounted in toluene-based media. To overcome such problem, three toluene-free mountants were tested on preserve Acanthamoeba spp and gregarines. Two commercial glues based on cyanoacrylate or trimethoxysilane were suitable for preserving both cysts and trophozoites. Hoyer's medium showed good results for mounting gregarine oocysts. Copyright © 2014 Elsevier B.V. All rights reserved.

Identification and Analysis of Putative Homologues of Mechanosensitive Channels in Pathogenic Protozoa

PubMed Central

Prole, David L.; Taylor, Colin W.

2013-01-01

Mechanosensitive channels play important roles in the physiology of many organisms, and their dysfunction can affect cell survival. This suggests that they might be therapeutic targets in pathogenic organisms. Pathogenic protozoa lead to diseases such as malaria, dysentery, leishmaniasis and trypanosomiasis that are responsible for millions of deaths each year worldwide. We analyzed the genomes of pathogenic protozoa and show the existence within them of genes encoding putative homologues of mechanosensitive channels. Entamoeba histolytica, Leishmania spp., Trypanosoma cruzi and Trichomonas vaginalis have genes encoding homologues of Piezo channels, while most pathogenic protozoa have genes encoding homologues of mechanosensitive small-conductance (MscS) and K+-dependent (MscK) channels. In contrast, all parasites examined lack genes encoding mechanosensitive large-conductance (MscL), mini-conductance (MscM) and degenerin/epithelial Na+ (DEG/ENaC) channels. Multiple sequence alignments of evolutionarily distant protozoan, amoeban, plant, insect and vertebrate Piezo channel subunits define an absolutely conserved motif that may be involved in channel conductance or gating. MscS channels are not present in humans, and the sequences of protozoan and human homologues of Piezo channels differ substantially. This suggests the possibility for specific targeting of mechanosensitive channels of pathogens by therapeutic drugs. PMID:23785469

The efficacy of biocides and other chemical additives in cooling water systems in the control of amoebae.

PubMed

Critchley, M; Bentham, R

2009-03-01

In vitro experiments were undertaken to evaluate biocide formulations commonly used in cooling water systems against protozoa previously isolated from cooling towers. The investigations evaluated the efficacy of these formulations against amoebic cysts and trophozoites. Laboratory challenges against protozoa isolated from cooling towers using chlorine, bromine and isothiazolinone biocides showed that all were effective after 4 h. The presence of molybdate and organic phosphates resulted in longer kill times for bromine and isothiazolinones. All treatments resulted in no detectable viable protozoa after 4 h of exposure. The chemical disinfection of planktonic protozoa in cooling water systems is strongly influenced by the residence time of the formulation and less so by its active constituent. Bromine and isothiazolinone formulations may require higher dosage of concentrations than currently practiced if used in conjunction with molybdate- and phosphate-based scale/corrosion inhibitors. Cooling water systems are complex microbial ecosystems in which predator-prey relationships play a key role in the dissemination of Legionella. This study demonstrated that at recommended dosing concentrations, biocides had species-specific effects on environmental isolates of amoebae that may act as reservoirs for Legionella multiplication in cooling water systems.

21 CFR 558.555 - Semduramicin.

Code of Federal Regulations, 2014 CFR

2014-04-01

... paragraph (d)(1) of this section; for prevention of necrotic enteritis caused by Clostridium perfringens...; for prevention of necrotic enteritis caused by C. perfringens susceptible to virginiamycin. Feed...

Evaluation of multiplex tandem real-time PCR for detection of Cryptosporidium spp., Dientamoeba fragilis, Entamoeba histolytica, and Giardia intestinalis in clinical stool samples.

PubMed

Stark, D; Al-Qassab, S E; Barratt, J L N; Stanley, K; Roberts, T; Marriott, D; Harkness, J; Ellis, J T

2011-01-01

The aim of this study was to describe the first development and evaluation of a multiplex tandem PCR (MT-PCR) assay for the detection and identification of 4 common pathogenic protozoan parasites, Cryptosporidium spp., Dientamoeba fragilis, Entamoeba histolytica, and Giardia intestinalis, from human clinical samples. A total of 472 fecal samples submitted to the Department of Microbiology at St. Vincent's Hospital were included in the study. The MT-PCR assay was compared to four real-time PCR (RT-PCR) assays and microscopy by a traditional modified iron hematoxylin stain. The MT-PCR detected 28 G. intestinalis, 26 D. fragilis, 11 E. histolytica, and 9 Cryptosporidium sp. isolates. Detection and identification of the fecal protozoa by MT-PCR demonstrated 100% correlation with the RT-PCR results, and compared to RT-PCR, MT-PCR exhibited 100% sensitivity and specificity, while traditional microscopy of stained fixed fecal smears exhibited sensitivities and specificities of 56% and 100% for Cryptosporidium spp., 38% and 99% for D. fragilis, 47% and 97% for E. histolytica, and 50% and 100% for G. intestinalis. No cross-reactivity was detected in 100 stool samples containing various other bacterial, viral, and protozoan species. The MT-PCR assay was able to provide rapid, sensitive, and specific simultaneous detection and identification of the four most important diarrhea-causing protozoan parasites that infect humans. This study also highlights the lack of sensitivity demonstrated by microscopy, and thus, molecular methods such as MT-PCR must be considered the diagnostic methods of choice for enteric protozoan parasites.

Prevalence and Genetic Diversity of Norovirus Among Patients With Acute Diarrhea in Guatemala

PubMed Central

Estévez, Alejandra; Arvelo, Wences; Hall, Aron J.; López, María R.; López, Beatriz; Reyes, Lissette; Moir, Juan Carlos; Gregoricus, Nicole; Vinjé, Jan; Parashar, Umesh D.; Lindblade, Kim A.

2015-01-01

Noroviruses (NoVs) are a leading cause of acute gastroenteritis outbreaks and sporadic cases of diarrhea in industrialized countries. To study the prevalence and genetic diversity of NoVs in Guatemala, stool specimens were collected from hospitalized and ambulatory patients presenting with diarrhea (≥3 loose or liquid stools in a 24-hr period) who were enrolled in a prospective surveillance system in the Departments of Santa Rosa (October 2007 to August 2010) and Quetzaltenango (August 2009 to August 2010), Guatemala. Specimens were tested for rotavirus, enteric bacteria, and parasites by routine methods and for genogroups I and II NoV by real-time reverse transcription-PCR. A total of 2,403 stool specimens were collected from hospitalized (n = 528) and ambulatory patients (n = 1,875). Overall, 341 (14%) samples tested positive for NoVs including 114 (22%) hospitalized and 227 (12%) ambulatory patients. NoVs disease peaked during the winter (November–January) months. Among the 341 NoVs-positive patients, 32 (9%) were also positive for rotavirus, 32 (9%) for bacteria, and 9 (3%) for protozoa. Nucleotide sequences were obtained from 84 samples collected from hospitalized children aged <5 years of age, which could be grouped into nine GII and three GI genotypes with GII.4 (74%) and GI.8 (10%) being the most common. This is the first study on the prevalence of NoVs among hospitalized and ambulatory patients with diarrhea in Guatemala. The findings highlight the need to implement laboratory diagnostics for NoVs to improve appropriate clinical management of diarrheal diseases and guide vaccine development. PMID:23595770

Importance of ticks and their chemical and immunological control in livestock*

PubMed Central

Rajput, Zahid Iqbal; Hu, Song-hua; Chen, Wan-jun; Arijo, Abdullah G.; Xiao, Chen-wen

2006-01-01

The medical and economic importance of ticks has long been recognized due to their ability to transmit diseases to humans and animals. Ticks cause great economic losses to livestock, and adversely affect livestock hosts in several ways. Loss of blood is a direct effect of ticks acting as potential vector for haemo-protozoa and helminth parasites. Blood sucking by large numbers of ticks causes reduction in live weight and anemia among domestic animals, while their bites also reduce the quality of hides. However, major losses caused by ticks are due to their ability to transmit protozoan, rickettsial and viral diseases of livestock, which are of great economic importance world-wide. There are quite a few methods for controlling ticks, but every method has certain shortcomings. The present review is focused on ticks importance and their control. PMID:17048307

Lymph nodes fine needle cytology in the diagnosis of infectious diseases: clinical settings.

PubMed

Natella, Valentina; Cozzolino, Immacolata; Sosa Fernandez, Laura Virginia; Vigliar, Elena

2012-01-01

Lymph node reactive hyperplasia, caused by specific infectious etiologic factors, represents the most frequent cause of enlarged peripheral lymph nodes. The main infectious agents are viruses, pyogenic bacteria, mycobacteria, fungi and protozoa that may determine unspecific or specific pathological entities, such as cat-scratch disease, toxoplasmosis or infectious mononucleosis. Lymph node fine needle cytology (FNC) is a safe, simple, cost-effective and efficient technique that quickly provides information about the cell population and the nature of the process. FNC can also provide suitable material for ancillary techniques, such as flow cytometry, immunocytochemistry, molecular biology and microbiological examinations. This study focuses on the cytological features of benign lymphadenopathy of infectious origin and their possible contribution to the clinical setting definition of corresponding patients.

21 CFR 520.2345d - Tetracycline powder.

Code of Federal Regulations, 2010 CFR

2010-04-01

... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia associated with Pasteurella spp., A... Mycoplasma gallisepticum and E. coli; control of infectious synovitis caused by M. synoviae susceptible to... of bacterial enteritis (scours) caused by Escherichia coli and bacterial pneumonia (shipping fever...

21 CFR 520.2345d - Tetracycline powder.

Code of Federal Regulations, 2011 CFR

2011-04-01

... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia associated with Pasteurella spp., A... gallisepticum and E. coli; control of infectious synovitis caused by M. synoviae susceptible to tetracycline.... Control and treatment of bacterial enteritis (scours) caused by Escherichia coli and bacterial pneumonia...

Spatio-temporal variability of periphytic protozoa related to environment in the Niyang River, Tibet, China

NASA Astrophysics Data System (ADS)

Liu, Haiping; Ye, Shaowen; Yang, Xuefeng; Guo, Chuanbo; Zhang, Huijuan; Fan, Liqing; Zhang, Liangsong; Sovan, Lek; Li, Zhongjie

2017-05-01

The Niyang River, a main tributary of the Yarlung Zangbo River, is an important and typical plateau river ecosystem in Tibet, China. At present, few studies have focused on its aquatic living resources and river ecology. In this study, the composition, abundance, and diversity of periphytic protozoa were investigated across four seasons from 2008 to 2009 to better understand their spatio-temporal patterns and relationship to the environment. Our investigation shows that periphytic protozoa in the Niyang River contained 15 genera, belonged to Tubulinea, Alveolata, Discosea and Rhizaria, Alveolata possessed most genera, up to nine, with highest share in abundance, exceeding 50%, Difflugia and Glaucoma were dominant genera. Moreover, four diversity indices of periphytic protozoa, including species richness, total abundance, Shannon-Wiener diversity index and Pielou's evenness index, displayed a significant descending trend as the seasons continued, in the order of winter, spring, summer and autumn; with a significant difference existing between winter and summer (or autumn) for Shannon-Wiener diversity index and species richness ( P<0.05). Four of these diversity indices also presented a V-shaped pattern between the upper middle course of the Niyang River and the confluence of the Niyang River and Yarlung Zangbo River, with the lowest value occurred in the middle course of the Niyang River. However, no significant variation was found through the Niyang River ( P>0.05). In addition, canonical correlation analysis (CCA) shows that the densities of Difflugia, Glaucomais, Enchelydium, Cyphoderia, and Enchelys correlate with water temperature, alkalinity, hardness, pH, and dissolved oxygen, respectively. Lastly, the relationship between periphytic protozoa diversity and the environmental factors of the Niyang River can be predicted using classification and regression trees (CART) annalysis, which suggests that the total abundance and Shannon-Wiener diversity index would be higher when the elevation is above 3 308 m. On the other hand, the Shannon-Wiener diversity index and Pielou's evenness index would be lower when pH and ammoniacal nitrogen have lower or higher values. Finally yet importantly, close attention should be paid to periphytic protozoa and its environment to ensure sustainable development of the Niyang River ecosystem.

Effect of sanitation and water treatment on intestinal protozoa infection: a systematic review and meta-analysis.

PubMed

Speich, Benjamin; Croll, David; Fürst, Thomas; Utzinger, Jürg; Keiser, Jennifer

2016-01-01

Pathogenic intestinal protozoa infections are responsible for substantial mortality and morbidity, particularly in settings where people lack improved sanitation and safe drinking water. We assessed the relation between access to, and use of, sanitation facilities and water treatment and infection with intestinal protozoa. We did a systematic review and searched PubMed, ISI Web of Science, and Embase from inception to June 30, 2014, without restrictions on language. All publications were examined by two independent reviewers and were included if they presented data at the individual level about access or use of sanitation facilities or water treatment, in combination with individual-level data on human intestinal protozoa infections. Meta-analyses using random effects models were used to calculate overall estimates. 54 studies were included and odds ratios (ORs) extracted or calculated from 2 × 2 contingency tables. The availability or use of sanitation facilities was associated with significantly lower odds of infection with Entamoeba histolytica or Entamoeba dispar (OR 0·56, 95% CI 0·42-0·74) and Giardia intestinalis (0·64, 0·51-0·81), but not for Blastocystis hominis (1·03, 0·87-1·23), and Cryptosporidium spp (0·68, 0·17-2·68). Water treatment was associated with significantly lower odds of B hominis (0·52, 0·34-0·78), E histolytica or E dispar (0·61, 0·38-0·99), G intestinalis (0·63, 0·50-0·80), and Cryptosporidium spp infections (0·83, 0·70-0·98). Availability and use of sanitation facilities and water treatment is associated with lower odds of intestinal protozoa infections. Interventions that focus on water and sanitation, coupled with hygiene behaviour, should be emphasised to sustain the control of intestinal protozoa infections. Swiss National Science Foundation (project numbers PBBSP3-146869 and P300P3-154634), Medicor Foundation, European Research Council (614739-A_HERO). Copyright © 2016 Elsevier Ltd. All rights reserved.

Prevalence and risk factors of intestinal protozoan and helminth infections among pulmonary tuberculosis patients without HIV infection in a rural county in P. R. China.

PubMed

Li, Xin-Xu; Chen, Jia-Xu; Wang, Li-Xia; Tian, Li-Guang; Zhang, Yu-Ping; Dong, Shuang-Pin; Hu, Xue-Guang; Liu, Jian; Wang, Feng-Feng; Wang, Yue; Yin, Xiao-Mei; He, Li-Jun; Yan, Qiu-Ye; Zhang, Hong-Wei; Xu, Bian-Li; Zhou, Xiao-Nong

2015-09-01

Although co-infection of tuberculosis (TB) and intestinal parasites, including protozoa and helminths, in humans has been widely studied globally, very little of this phenomenon is known in China. Therefore, a cross-sectional study was conducted in a rural county of China to investigate such co-infections. Patients with pulmonary TB (PTB) undergoing anti-Mycobacterium tuberculosis (anti-MTB) treatment were surveyed by questionnaires, and their feces and blood specimens were collected for detection of intestinal protozoa and helminths, routine blood examination and HIV detection. The χ(2) test and multivariate logistic regression model were used to identify risk factors. A total of 369 patients with PTB were included and all of them were HIV negative. Overall, only 7.3% of participants were infected with intestinal protozoa, among which prevalence of Blastocystis hominis, Entamoeba spp. and Trichomonas hominis were 6.0%, 1.1% and 0.3%, respectively; 7.0% were infected with intestinal helminths, among which prevalence of hookworm, Trichuris trichiura, Ascaris lumbricoides and Clonorchis sinensis were 4.3%, 1.9%, 0.5% and 0.3%, respectively; and 0.5% were simultaneously infected with intestinal protozoa and helminths. Among patients with PTB, body mass index (BMI)≤18 (OR=3.30, 95% CI=1.44-7.54) and raised poultry or livestock (e.g., chicken, duck, pig) (OR=3.96, 95% CI=1.32-11.89) were significantly associated with harboring intestinal protozoan infection, while BMI≤18 (OR=3.32, 95% CI=1.39-7.91), anemia (OR=3.40, 95% CI=1.44-8.02) and laboring barefoot in farmlands (OR=4.54, 95% CI=1.88-10.92) were significantly associated with having intestinal helminth infection. Additionally, there was no significant relationship between duration of anti-MTB treatment and infection rates of intestinal parasites including protozoa and helminths. Therefore, preventing malnutrition, avoiding unprotected contact with reservoirs of protozoa, and improving health education for good hygiene habits, particularly wearing shoes while outdoors, are beneficial in the prevention of intestinal protozoan and helminth infection among patients with PTB. Copyright © 2015 Elsevier B.V. All rights reserved.

21 CFR 520.2345d - Tetracycline powder.

Code of Federal Regulations, 2013 CFR

2013-04-01

.... Control and treatment of bacterial enteritis (scours) caused by Escherichia coli and bacterial pneumonia... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia associated with Pasteurella spp., A...

21 CFR 520.2345d - Tetracycline powder.

Code of Federal Regulations, 2014 CFR

2014-04-01

.... Control and treatment of bacterial enteritis (scours) caused by Escherichia coli and bacterial pneumonia... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia associated with Pasteurella spp., A...

21 CFR 520.2345d - Tetracycline powder.

Code of Federal Regulations, 2012 CFR

2012-04-01

.... Control and treatment of bacterial enteritis (scours) caused by Escherichia coli and bacterial pneumonia... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia associated with Pasteurella spp., A...

Splenitis in 33 Dogs.

PubMed

Ferri, F; Zini, E; Auriemma, E; Castagnaro, M; Coppola, L M; Peano, A; Martella, V; Decaro, N; Kuhnert, P; Ferro, S

2017-01-01

Splenitis is uncommonly reported in dogs. Herein, the authors describe its prevalence, clinical findings and outcomes, histologic patterns, and causes. Splenic samples of dogs diagnosed with splenitis between 2005 and 2013 were collected and stained with hematoxylin and eosin, Gram, green-Gram, Giemsa, periodic acid-Schiff, and Ziehl-Neelsen. Samples were processed for polymerase chain reaction (PCR) to detect bacteria, fungi, and protozoa ( Leishmania infantum, Hepatozoon canis). Thirty-three of 660 splenic samples (5%) had splenitis. Clinical findings and outcomes were available in 19 dogs (58%); 49% had weakness, 33% had fever, and 84% survived. The most frequent inflammatory patterns included purulent splenitis (27%), pyogranulomatous splenitis (24%), and neutrophilic perisplenitis (15%). One dog had a putative diagnosis of primary splenitis; in 8 dogs, microorganisms were identified histologically or by PCR in the spleen without obvious comorbidities. Twenty-four dogs (73%) had concurrent diseases; a permissive role in the development of splenitis was suspected in 21 of these cases. Histologic examination identified the cause of splenitis in 10 dogs. Bacteria were identified by PCR in 23 cases, but the bacteria were confirmed histologically in only 6 of these. Leishmania was detected with PCR in 6 dogs. Leishmania was identified in 1 dog and H. canis in another histologically, but both were PCR negative. Fungi were identified in 8 spleens by PCR and in 1 by histology. This study suggests that splenitis is uncommon in dogs and is frequently associated with systemic diseases. Prognosis is favorable in most cases. Identification of bacteria, fungi, and protozoa in the spleens of affected dogs with PCR should be interpreted cautiously, because the findings are not confirmed histologically in many cases.

Persistent digestive disorders in the tropics: causative infectious pathogens and reference diagnostic tests

PubMed Central

2013-01-01

Background Persistent digestive disorders account for considerable disease burden in the tropics. Despite advances in understanding acute gastrointestinal infections, important issues concerning epidemiology, diagnosis, treatment and control of most persistent digestive symptomatologies remain to be elucidated. Helminths and intestinal protozoa are considered to play major roles, but the full extent of the aetiologic spectrum is still unclear. We provide an overview of pathogens causing digestive disorders in the tropics and evaluate available reference tests. Methods We searched the literature to identify pathogens that might give rise to persistent diarrhoea, chronic abdominal pain and/or blood in the stool. We reviewed existing laboratory diagnostic methods for each pathogen and stratified them by (i) microscopy; (ii) culture techniques; (iii) immunological tests; and (iv) molecular methods. Pathogen-specific reference tests providing highest diagnostic accuracy are described in greater detail. Results Over 30 pathogens may cause persistent digestive disorders. Bacteria, viruses and parasites are important aetiologic agents of acute and long-lasting symptomatologies. An integrated approach, consisting of stool culture, microscopy and/or specific immunological techniques for toxin, antigen and antibody detection, is required for accurate diagnosis of bacteria and parasites. Molecular techniques are essential for sensitive diagnosis of many viruses, bacteria and intestinal protozoa, and are increasingly utilised as adjuncts for helminth identification. Conclusions Diagnosis of the broad spectrum of intestinal pathogens is often cumbersome. There is a need for rapid diagnostic tests that are simple and affordable for resource-constrained settings, so that the management of patients suffering from persistent digestive disorders can be improved. PMID:23347408

An orthology-based analysis of pathogenic protozoa impacting global health: an improved comparative genomics approach with prokaryotes and model eukaryote orthologs.

PubMed

Cuadrat, Rafael R C; da Serra Cruz, Sérgio Manuel; Tschoeke, Diogo Antônio; Silva, Edno; Tosta, Frederico; Jucá, Henrique; Jardim, Rodrigo; Campos, Maria Luiza M; Mattoso, Marta; Dávila, Alberto M R

2014-08-01

A key focus in 21(st) century integrative biology and drug discovery for neglected tropical and other diseases has been the use of BLAST-based computational methods for identification of orthologous groups in pathogenic organisms to discern orthologs, with a view to evaluate similarities and differences among species, and thus allow the transfer of annotation from known/curated proteins to new/non-annotated ones. We used here a profile-based sensitive methodology to identify distant homologs, coupled to the NCBI's COG (Unicellular orthologs) and KOG (Eukaryote orthologs), permitting us to perform comparative genomics analyses on five protozoan genomes. OrthoSearch was used in five protozoan proteomes showing that 3901 and 7473 orthologs can be identified by comparison with COG and KOG proteomes, respectively. The core protozoa proteome inferred was 418 Protozoa-COG orthologous groups and 704 Protozoa-KOG orthologous groups: (i) 31.58% (132/418) belongs to the category J (translation, ribosomal structure, and biogenesis), and 9.81% (41/418) to the category O (post-translational modification, protein turnover, chaperones) using COG; (ii) 21.45% (151/704) belongs to the categories J, and 13.92% (98/704) to the O using KOG. The phylogenomic analysis showed four well-supported clades for Eukarya, discriminating Multicellular [(i) human, fly, plant and worm] and Unicellular [(ii) yeast, (iii) fungi, and (iv) protozoa] species. These encouraging results attest to the usefulness of the profile-based methodology for comparative genomics to accelerate semi-automatic re-annotation, especially of the protozoan proteomes. This approach may also lend itself for applications in global health, for example, in the case of novel drug target discovery against pathogenic organisms previously considered difficult to research with traditional drug discovery tools.

An Orthology-Based Analysis of Pathogenic Protozoa Impacting Global Health: An Improved Comparative Genomics Approach with Prokaryotes and Model Eukaryote Orthologs

PubMed Central

Cuadrat, Rafael R. C.; da Serra Cruz, Sérgio Manuel; Tschoeke, Diogo Antônio; Silva, Edno; Tosta, Frederico; Jucá, Henrique; Jardim, Rodrigo; Campos, Maria Luiza M.; Mattoso, Marta

2014-01-01

Abstract A key focus in 21st century integrative biology and drug discovery for neglected tropical and other diseases has been the use of BLAST-based computational methods for identification of orthologous groups in pathogenic organisms to discern orthologs, with a view to evaluate similarities and differences among species, and thus allow the transfer of annotation from known/curated proteins to new/non-annotated ones. We used here a profile-based sensitive methodology to identify distant homologs, coupled to the NCBI's COG (Unicellular orthologs) and KOG (Eukaryote orthologs), permitting us to perform comparative genomics analyses on five protozoan genomes. OrthoSearch was used in five protozoan proteomes showing that 3901 and 7473 orthologs can be identified by comparison with COG and KOG proteomes, respectively. The core protozoa proteome inferred was 418 Protozoa-COG orthologous groups and 704 Protozoa-KOG orthologous groups: (i) 31.58% (132/418) belongs to the category J (translation, ribosomal structure, and biogenesis), and 9.81% (41/418) to the category O (post-translational modification, protein turnover, chaperones) using COG; (ii) 21.45% (151/704) belongs to the categories J, and 13.92% (98/704) to the O using KOG. The phylogenomic analysis showed four well-supported clades for Eukarya, discriminating Multicellular [(i) human, fly, plant and worm] and Unicellular [(ii) yeast, (iii) fungi, and (iv) protozoa] species. These encouraging results attest to the usefulness of the profile-based methodology for comparative genomics to accelerate semi-automatic re-annotation, especially of the protozoan proteomes. This approach may also lend itself for applications in global health, for example, in the case of novel drug target discovery against pathogenic organisms previously considered difficult to research with traditional drug discovery tools. PMID:24960463

Alteration of Rumen Bacteria and Protozoa Through Grazing Regime as a Tool to Enhance the Bioactive Fatty Acid Content of Bovine Milk

PubMed Central

Bainbridge, Melissa L.; Saldinger, Laurel K.; Barlow, John W.; Alvez, Juan P.; Roman, Joe; Kraft, Jana

2018-01-01

Rumen microorganisms are the origin of many bioactive fatty acids (FA) found in ruminant-derived food products. Differences in plant leaf anatomy and chemical composition between cool- and warm-season pastures may alter rumen microorganisms, potentially enhancing the quantity/profile of bioactive FA available for incorporation into milk. The objective of this study was to identify rumen bacteria and protozoa and their cellular FA when cows grazed a warm-season annual, pearl millet (PM), in comparison to a diverse cool-season pasture (CSP). Individual rumen digesta samples were obtained from five Holstein cows in a repeated measures design with 28-day periods. The treatment sequence was PM, CSP, then PM. Microbial DNA was extracted from rumen digesta and sequence reads were produced with Illumina MiSeq. Fatty acids (FA) were identified in rumen bacteria and protozoa using gas-liquid chromatography/mass spectroscopy. Microbial communities shifted in response to grazing regime. Bacteria of the phylum Bacteroidetes were more abundant during PM than CSP (P < 0.05), while protozoa of the genus Eudiplodinium were more abundant during CSP than PM (P < 0.05). Microbial cellular FA profiles differed between treatments. Bacteria and protozoa from cows grazing CSP contained more n-3 FA (P < 0.001) and vaccenic acid (P < 0.01), but lower proportions of branched-chain FA (P < 0.05). Microbial FA correlated with microbial taxa and levels of vaccenic acid, rumenic acid, and α-linolenic acid in milk. In conclusion, grazing regime can potentially be used to alter microbial communities shifting the FA profile of microbial cells, and subsequently, alter the milk FA profile. PMID:29867815

Alteration of Rumen Bacteria and Protozoa Through Grazing Regime as a Tool to Enhance the Bioactive Fatty Acid Content of Bovine Milk.

PubMed

Bainbridge, Melissa L; Saldinger, Laurel K; Barlow, John W; Alvez, Juan P; Roman, Joe; Kraft, Jana

2018-01-01

Rumen microorganisms are the origin of many bioactive fatty acids (FA) found in ruminant-derived food products. Differences in plant leaf anatomy and chemical composition between cool- and warm-season pastures may alter rumen microorganisms, potentially enhancing the quantity/profile of bioactive FA available for incorporation into milk. The objective of this study was to identify rumen bacteria and protozoa and their cellular FA when cows grazed a warm-season annual, pearl millet (PM), in comparison to a diverse cool-season pasture (CSP). Individual rumen digesta samples were obtained from five Holstein cows in a repeated measures design with 28-day periods. The treatment sequence was PM, CSP, then PM. Microbial DNA was extracted from rumen digesta and sequence reads were produced with Illumina MiSeq. Fatty acids (FA) were identified in rumen bacteria and protozoa using gas-liquid chromatography/mass spectroscopy. Microbial communities shifted in response to grazing regime. Bacteria of the phylum Bacteroidetes were more abundant during PM than CSP ( P < 0.05), while protozoa of the genus Eudiplodinium were more abundant during CSP than PM ( P < 0.05). Microbial cellular FA profiles differed between treatments. Bacteria and protozoa from cows grazing CSP contained more n-3 FA ( P < 0.001) and vaccenic acid ( P < 0.01), but lower proportions of branched-chain FA ( P < 0.05). Microbial FA correlated with microbial taxa and levels of vaccenic acid, rumenic acid, and α-linolenic acid in milk. In conclusion, grazing regime can potentially be used to alter microbial communities shifting the FA profile of microbial cells, and subsequently, alter the milk FA profile.

What are the taxonomic and evolutionary relationships of the Protozoa to the Protista?

PubMed

Corliss, J O

1981-01-01

In order to consider the problems of protist-protozoan interrelationships in proper perspective, a new "packaging" of phyla within the great kingdom Protista is proposed. Although it is based largely on historical groupings and is admittedly "unnatural" (nor are taxonomic names proposed for my five supraphyletic groupings), the arrangement may clarify some long-persisting problems, especially with regard to mixed algal-protozoan groups and/or phylogenies. Some three dozen phyla are recognized as comprising the kingdom, with the number that might be considered as "protozoan" ranging from 10 to 25, depending on one's viewpoint. No taxon should have the formal name "Protozoa", "Phytoflagellate" and "zooflagellate" are also misleading categories. Taxonomic and evolutionary relationships of phyla containing protozoa (with small "p") are inextricably intermeshed with those of other protist phyla, and thus no unified protozoan super-group exists.

21 CFR 520.445b - Chlortetracycline powder.

Code of Federal Regulations, 2011 CFR

2011-04-01

.... (1) Control and treatment of bacterial enteritis (scours) caused by E. coli and bacterial pneumonia.... Control of chronic respiratory disease and air-sac infections caused by M. gallisepticum and E. coli. (2.... (B) Indications for use. Control and treatment of bacterial enteritis (scours) caused by E. coli and...

21 CFR 520.445b - Chlortetracycline powder.

Code of Federal Regulations, 2010 CFR

2010-04-01

.... (1) Control and treatment of bacterial enteritis (scours) caused by E. coli and bacterial pneumonia.... Control of chronic respiratory disease and air-sac infections caused by M. gallisepticum and E. coli. (2.... (B) Indications for use. Control and treatment of bacterial enteritis (scours) caused by E. coli and...

Diversity of Heterotrophic Protists from Extremely Hypersaline Habitats.

PubMed

Park, Jong Soo; Simpson, Alastair G B

2015-09-01

Heterotrophic protists (protozoa) are a diverse but understudied component of the biota of extremely hypersaline environments, with few data on molecular diversity within halophile 'species', and almost nothing known of their biogeographic distribution. We have garnered SSU rRNA gene sequences for several clades of halophilic protozoa from enrichments from waters of >12.5% salinity from Australia, North America, and Europe (6 geographic sites, 25 distinct samples). The small stramenopile Halocafeteria was found at all sites, but phylogenies did not show clear geographic clustering. The ciliate Trimyema was recorded from 6 non-European samples. Phylogenies confirmed a monophyletic halophilic Trimyema group that included possible south-eastern Australian, Western Australian and North American clusters. Several halophilic Heterolobosea were detected, demonstrating that Pleurostomum contains at least three relatively distinct clades, and increasing known continental ranges for Tulamoeba peronaphora and Euplaesiobystra hypersalinica. The unclassified flagellate Palustrimonas, found in one Australian sample, proves to be a novel deep-branching alveolate. These results are consistent with a global distribution of halophilic protozoa groups (∼ morphospecies), but the Trimyema case suggests that is worth testing whether larger forms exhibit biogeographic phylogenetic substructure. The molecular detection/characterization of halophilic protozoa is still far from complete at the clade level, let alone the 'species level'. Copyright © 2015 Elsevier GmbH. All rights reserved.

Correlation between iron deficiency anemia and intestinal parasitic infection in school-age children in Medan

NASA Astrophysics Data System (ADS)

Darlan, D. M.; Ananda, F. R.; Sari, M. I.; Arrasyid, N. K.; Sari, D. I.

2018-03-01

Anemia is an abnormal hemoglobin concentration in blood that impacts almost 40% school-age children in developing countries. Intestinal parasitic infection, along with malnutrition are contributed to influence absorption, transportation, and metabolism of iron which is the most common etiology of anemia in school-age children. The purpose of this study was to determine whether there is a correlation between iron deficiency anemia (IDA) and parasitic intestinal infection generally and protozoa infection particularly among school-age children in Medan. This was a cross-sectional study conducted from May until October 2016 in primaryschool in Medan and Hamparan Perak, Deli Serdang. Consecutive sampling was used with total 132 samples obtained. Univariate analysis and Bivariate analysis were performed.This study showed the prevalence of IDA was 7.6%, and proportion of parasitic intestinal infection was 26.5% with 19.8% protozoa infection. The correlation between IDA and intestinal parasitic infection was not significant in Chi-Square Test (p-value: 0.089), neither was between IDA and protozoa infection (p-value: 0.287). There was a correlation between MCV, MCH, and anemia with p-value<0.05. However, there was no correlation among other IDA variables such as Serum Iron, TIBC, ferritin, related to age, anemia, parasitic infection, and protozoa infection (p-value>0.05).

Reduction of Cryptosporidium, Giardia, and Fecal Indicators by Bardenpho Wastewater Treatment.

PubMed

Schmitz, Bradley W; Moriyama, Hitoha; Haramoto, Eiji; Kitajima, Masaaki; Sherchan, Samendra; Gerba, Charles P; Pepper, Ian L

2018-06-19

Increased demand for water reuse and reclamation accentuates the importance for optimal wastewater treatment to limit protozoa in effluents. Two wastewater treatment plants utilizing advanced Bardenpho were investigated over a 12-month period to determine the incidence and reduction of Cryptosporidium, Giardia, Cyclospora, and fecal indicators. Results were compared to facilities that previously operated in the same geographical area. Protozoa (oo)cysts were concentrated using an electronegative filter and subsequently detected by fluorescent microscopy and/or PCR methods. Cryptosporidium and Giardia were frequently detected in raw sewage, but Cyclospora was not detected in any wastewater samples. Facilities with Bardenpho treatment exhibited higher removals of (oo)cysts than facilities utilizing activated sludge or trickling filters. This was likely due to Bardenpho systems having increased solid wasting rates; however, this mechanism cannot be confirmed as sludge samples were not analyzed. Use of dissolved-air-flotation instead of sedimentation tanks did not result in more efficient removal of (oo)cysts. Concentrations of protozoa were compared with each other, Escherichia coli, somatic coliphage, and viruses (pepper mild mottle virus, Aichi virus 1, adenovirus, and polyomaviruses JC and BK). Although significant correlations were rare, somatic coliphage showed the highest potential as an indicator for the abundance of protozoa in wastewaters.

The prevalence of protozoa in the gut of German cockroaches (Blattella germanica) with special reference to Lophomonas blattarum.

PubMed

Martínez-Girón, Rafael; Martínez-Torre, Cristina; van Woerden, Hugo Cornelis

2017-11-01

The German cockroach (Blattella germanica) is a common domestic pest, which produces allergens that have been associated with broncho-pulmonary disease. Various protozoan species have been identified in the intestine of this cockroach and it has been hypothesised that these protozoa, or their proteases, may contribute to the burden of cockroach-associated allergens and adjuvants present in domestic dust. The aim of this study was therefore to determine the prevalence of protozoan species in the intestine of Blattella germanica. German cockroaches were anesthetised and dissected and gut contents are used to produce wet slides for microscopy. Both, Giemsa and Papanicolaou stains were used to confirm correct identification of Lophomonas blattarum. Representatives of four genera of protozoa were identified in 110 cockroaches: Nyctoterus sp. was observed in 91.8% of cases, Gregarina sp. in 64.5%, Amoeba sp. in 25.4% and Lophomonas blattarum in 13.6%. Nyctoterus and Gregarina were statistically significantly more likely to be found in diseased cockroaches compared to Amoeba or Lophomonas. The prevalence of Lophomonas blattarum was similar to that in published studies of a different species of cockroach, Periplaneta americana. Further work is needed to assess the interplay between protozoa, cockroaches and broncho-pulmonary diseases.

Influence of different anoxic time exposures on active biomass, protozoa and filamentous bacteria in activated sludge.

PubMed

Rodriguez-Perez, S; Fermoso, F G; Arnaiz, C

Medium-sized wastewater treatment plants are considered too small to implement anaerobic digestion technologies and too large for extensive treatments. A promising option as a sewage sludge reduction method is the inclusion of anoxic time exposures. In the present study, three different anoxic time exposures of 12, 6 and 4 hours have been studied to reduce sewage sludge production. The best anoxic time exposure was observed under anoxic/oxic cycles of 6 hours, which reduced 29.63% of the biomass production compared with the oxic control conditions. The sludge under different anoxic time exposures, even with a lower active biomass concentration than the oxic control conditions, showed a much higher metabolic activity than the oxic control conditions. Microbiological results suggested that both protozoa density and abundance of filamentous bacteria decrease under anoxic time exposures compared to oxic control conditions. The anoxic time exposures 6/6 showed the highest reduction in both protozoa density, 37.5%, and abundance of filamentous bacteria, 41.1%, in comparison to the oxic control conditions. The groups of crawling ciliates, carnivorous ciliates and filamentous bacteria were highly influenced by the anoxic time exposures. Protozoa density and abundance of filamentous bacteria have been shown as promising bioindicators of biomass production reduction.

21 CFR 558.455 - Oxytetracycline and neomycin.

Code of Federal Regulations, 2011 CFR

2011-04-01

... (air-sac- infection) caused by E. coli susceptible to oxytetracycline. Feed continuously for 5 d; do... treatment of bacterial enteritis caused by E. coli and Salmonella choleraesuis and treatment of bacterial... (bacterial enteritis) caused by E. coli susceptible to neomycin. Feed continuously for 7 to 14 d; withdraw 5...

21 CFR 558.455 - Oxytetracycline and neomycin.

Code of Federal Regulations, 2010 CFR

2010-04-01

... (air-sac- infection) caused by E. coli susceptible to oxytetracycline. Feed continuously for 5 d; do... treatment of bacterial enteritis caused by E. coli and Salmonella choleraesuis and treatment of bacterial... (bacterial enteritis) caused by E. coli susceptible to neomycin. Feed continuously for 7 to 14 d; withdraw 5...

Effects of illite supplementation on in vitro and in vivo rumen fermentation, microbial population and methane emission of Hanwoo steers fed high concentrate diets.

PubMed

Biswas, Ashraf A; Lee, Sung-Sill; Mamuad, Lovelia L; Kim, Seon-Ho; Choi, Yeon-Jae; Lee, Chanhee; Lee, Kichoon; Bae, Gui-Seck; Lee, Sang-Suk

2018-01-01

This study was conducted to evaluate the effects of feeding supplemental illite to Hanwoo steers on methane (CH 4 ) emission and rumen fermentation parameters. An in vitro ruminal fermentation technique was conducted using a commercial concentrate as substrate and illite was added at different concentrations as treatments: 0%, 0.5%, 1.0%, and 2.0% illite. Total volatile fatty acids (VFA) were different (P < 0.05) at 24 h of incubation where the highest total VFA was observed at 1.0% of illite. Conversely, lowest CH 4 production (P < 0.01) was found at 1.0% of illite. In the in vivo experiment, two diets were provided, without illite and with addition of 1% illite. An automated head chamber (GreenFeed) system was used to measure enteric CH 4 production. Cattle received illite supplemented feed increased (P < 0.05) total VFA concentrations in the rumen compared with those fed control. Feeding illite numerically decreased CH 4 production (g/day) and yield (g/kg dry matter intake). Rumen microbial population analysis indicated that the population of total bacteria, protozoa and methanogens were lower (P < 0.05) for illite compared with the control. Accordingly, overall results suggested that feeding a diet supplemented with 1% illite can have positive effects on feed fermentation in the rumen and enteric CH 4 mitigation in beef cattle. © 2017 Japanese Society of Animal Science.

Anti-Leishmania and cytotoxic activities of perillaldehyde epoxide synthetic positional isomers.

PubMed

Keesen, Tatjana Souza Lima; da Silva, Larisse Virgolino; da Câmara Rocha, Juliana; Andrade, Luciana Nalone; Lima, Tamires Cardoso; de Sousa, Damião Pergentino

2018-03-13

Leishmaniasis belongs to a complex of zoonotic disease caused by protozoa of the genus Leishmania and is considered a major public health problem. Several essential oil chemical components have inhibitory effect against protozoa, including Leishmania donovani. Thus, the aim of this study was to evaluate for the first time the anti-Leishmania activity of two p-menthane monoterpene isomers (EPER-1: perillaldehyde 1,2-epoxide and EPER-2: perillaldehyde 8,9-epoxide) against L. donovani promastigotes as well as evaluating cytotoxic effect on mononuclear peripheral blood cells. Results of anti-Leishmania assay revealed that EPER-2 (IC 50  = 3.8 μg.mL -1 ) was 16-fold more potent than its isomer EPER-1 (IC 50  = 64.6 μg.mL -1 ). In contrast to PBMC cells, EPER-2 was not cytotoxic (IC 50  > 400 μg.mL -1 ) when compared to positive control. These data suggest that the disposition of epoxide group into the p-menthane skeleton affects the anti-Leishmania activity, being that the presence of the exocyclic epoxide group considerably increased potency. Thus, it was possible to observe that the location of the epoxide group into the p-menthane skeleton resulted in different potencies.

Investigation of gastrointestinal parasites of dairy cattle around Taiwan.

PubMed

Huang, Chiu-Chen; Wang, Lian-Chen; Pan, Chien-Hung; Yang, Cheng-Hsiung; Lai, Cheng-Hung

2014-02-01

Parasitic nematodes are one of the most important causes of production losses in most cattle-producing countries of the world. The aim of the present study is to make a through estimate of helminth and protozoan infection prevalence in dairy cattle around Taiwan. Coprological techniques, including direct fecal smear, simple flotation, and simple sedimentation, were used to detect gastrointestinal helminths and protozoan in dairy cattle. A total of 1259 rectal fecal samples were collected from Holstein dairy cattle at 94 farms in 13 counties in Taiwan. The overall prevalence of gastrointestinal parasitic infection was 86.9%. The infection rates of protozoa, nematodes, trematodes, and cestodes were 81.3%, 7.9%, 1.6%, and 0.6%, respectively. Among all parasites, Buxtonella sulcata (61.7%) was the most predominant one, followed with Cryptosporidium spp. (32.6%) and Eimeria spp. (11.8%). There were significant differences in the prevalence of protozoa and nematodes between different age groups and distributional area groups. The present study demonstrated that gastrointestinal parasitic infections occur frequently in dairy cattle around Taiwan, especially protozoan infections. The results indicated that a superior management system and regular anthelmintic treatment should be used for the control of parasitic infections in dairy cattle farms. Copyright © 2012. Published by Elsevier B.V.

Rickettsiae, protozoa, and opisthokonta/metazoa.

PubMed

Schmutzhard, Erich; Helbok, Raimund

2014-01-01

Rhizobiales (formerly named Rickettsiales) cause in rare instances meningitis and meningovasculitis, respectively. In case of history of exposure, infection by Rhizobiales needs to be considered since both diagnosis and therapy may be extremely difficult and pathogen-specific. The same applies to protozoa; in this chapter, Babesia species, free-living amoebae and Entamoeba histolytica infection, including severe meningitis and brain abscess, infection by Trypanosoma species (South American and African trypanosomiasis) are discussed with respect to history, epidemiology, clinical signs, and symptoms as well as differential diagnosis and therapy. Parasitic flatworms and roundworms, potentially able to invade the central nervous system, trematodes (flukes), cestodes (in particular, Cysticercus cellulosae), but also nematodes (in particular, Strongyloides spp. in the immunocompromised) are of worldwide importance. In contrast, filarial worms, Toxocara spp., Trichinella spp., Gnathostoma and Angiostrongylus spp. are seen only in certain geographically confined areas. Even more regionally confined are infestations of the central nervous system by metazoa, in particular, tongue worms (=arthropods) or larvae of flies (=maggots). The aim of this chapter is (1) to alert the neurologist to these infections, and (2) to enable the attending emergency neurologist to take a knowledgeable history, with an emphasis on epidemiology, clinical signs, and symptoms as well as therapeutic management possibilities. © 2014 Elsevier B.V. All rights reserved.

Microbial Diffraction Gratings as Optical Detectors for Heavy Metal Pollutants

NASA Technical Reports Server (NTRS)

Noever, David; Matsos, Helen; Brittain, Andrew; Obenhuber, Don; Cronise, Raymond; Armstrong, Shannon

1996-01-01

As a significant industrial pollutant, cadmium is implicated as the cause of itai-itai disease. For biological detection of cadmium toxicity, an assay device has been developed using the motile response of the protozoa species, Tetrahymena pyriformis. This mobile protozoa measures 50 microns in diameter, swims at 10 body lengths per second, and aggregates into macroscopically visible patterns at high organism concentrations. The assay demonstrates a Cd(+2) sensitivity better than 1 micro-M and a toxicity threshold to 5 micro-M, thus encouraging the study of these microbial cultures as viable pollution detectors. Using two-dimensional diffraction patterns within a Tetrahymena culture, the scattered light intensity varies with different organism densities (population counts). The resulting density profile correlates strongly with the toxic effects at very low dosages for cadmium (less than 5 ppm) and then for poison protection directly (with nickel and copper antagonists competing with cadmium absorption). In particular, copper dosages as low as 0.1-0.5 mM Cu have shown protective antagonism against cadmium, have enhanced density variability for cultures containing 1 mM Cd(+2) and therefore have demonstrated the sensitivity of the optical detection system. In this way, such microbial diffraction patterns give a responsive optical measure of biological culture changes and toxicity determination in aqueous samples of heavy metals and industrial pollutants.

OCCURRENCE OF ENTERIC VIRUSES IN SURFACE WATERS

EPA Science Inventory

Human enteric viruses cause a number of diseases when individuals are exposed to contaminated drinking & recreational waters. Vaccination against poliovirus has virtually eliminated poliomyelitis from the planet. Other members of enterovirus group cause numerous diseases. Hepatit...

Recent advances in molecular biology of parasitic viruses.

PubMed

Banik, Gouri Rani; Stark, Damien; Rashid, Harunor; Ellis, John T

2014-01-01

The numerous protozoa that can inhabit the human gastro-intestinal tract are known, yet little is understood of the viruses which infect these protozoa. The discovery, morphologic details, purification methods of virus-like particles, genome and proteome of the parasitic viruses, Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis, and the Eimeria sp. are described in this review. The protozoan viruses share many common features: most of them are RNA or double-stranded RNA viruses, ranging between 5 and 8 kilobases, and are spherical or icosahedral in shape with an average diameter of 30-40 nm. These viruses may influence the function and pathogenicity of the protozoa which they infect, and may be important to investigate from a clinical perspective. The viruses may be used as specific genetic transfection vectors for the parasites and may represent a research tool. This review provides an overview on recent advances in the field of protozoan viruses.

Optical detection of parasitic protozoa in sol-gel matrices

NASA Astrophysics Data System (ADS)

Livage, Jacques; Barreau, J. Y.; Da Costa, J. M.; Desportes, I.

1994-10-01

Whole cell parasitic protozoa have been entrapped within sol-gel porous silica matrices. Stationary phase promastigote cells of Leishmania donovani infantum are mixed with a silica sol before gelation occurs. They remain trapped within the growing oxide network and their cellular organization appears to be well preserved. Moreover protozoa retain their antigenic properties in the porous gel. They are still able to detect parasite specific antibodies in serum samples from infected patients via an enzyme linked immunosorbent assay (ELISA). Antigen- antibody associations occurring in the gel are optically detected via the reactions of a peroxidase conjugate with ortho-phenylenediamine leading to the formation of a yellow coloration. A clear-cut difference in optical density is measured between positive and negative sera. Such an entrapment of antigenic species into porous sol-gel matrices avoids the main problems due to non specific binding and could be advantageously used in diagnostic kits.

Niche metabolism in parasitic protozoa

PubMed Central

Ginger, Michael L

2005-01-01

Complete or partial genome sequences have recently become available for several medically and evolutionarily important parasitic protozoa. Through the application of bioinformatics complete metabolic repertoires for these parasites can be predicted. For experimentally intractable parasites insight provided by metabolic maps generated in silico has been startling. At its more extreme end, such bioinformatics reckoning facilitated the discovery in some parasites of mitochondria remodelled beyond previous recognition, and the identification of a non-photosynthetic chloroplast relic in malarial parasites. However, for experimentally tractable parasites, mapping of the general metabolic terrain is only a first step in understanding how the parasite modulates its streamlined, yet still often puzzlingly complex, metabolism in order to complete life cycles within host, vector, or environment. This review provides a comparative overview and discussion of metabolic strategies used by several different parasitic protozoa in order to subvert and survive host defences, and illustrates how genomic data contribute to the elucidation of parasite metabolism. PMID:16553311

Development of a specific polymerase chain reaction assay for the detection of Basidiobolus.

PubMed

Gómez-Muñoz, María Teresa; Fernández-Barredo, Salceda; Martínez-Díaz, Rafael Alberto; Pérez-Gracia, María Teresa; Ponce-Gordo, Francisco

2012-01-01

The etiology of chronic diarrhea is complex in humans and animals. It is always necessary to evaluate a list of differential diagnosis, including bacteria, protozoa and fungi. Basidiobolomycosis is a fungal disease reported sporadically worldwide, mainly caused by B. ranarum, a frequent organism found in soil or in the intestine and skin of lizards and frogs. It is an opportunistic pathogen that causes infections characterized by granulomatous lesions in the subcutaneous tissues as well as in the intestinal wall in humans and animals. In this work we have developed a PCR technique to differentiate Basidiobolus from other causes of intestinal disease in dogs and humans. To test the specificity of the PCR assay we included closely related organisms, common intestinal microbiota and pathogenic organisms, such as Aspergillus, Candida, Cryptosporidium, Escherichia, Giardia, Mucor, Proteus, Rhizopus and Salmonella. Pythium insidiosum, which cause clinically similar disease in dogs but require a different treatment. Only Basidiobolus was positive to the PCR assay.

Psidium guajava L., from ethnobiology to scientific evaluation: Elucidating bioactivity against pathogenic microorganisms.

PubMed

Morais-Braga, Maria Flaviana B; Carneiro, Joara Nalyda P; Machado, Antonio Júdson T; Dos Santos, Antonia Thassya L; Sales, Débora L; Lima, Luciene F; Figueredo, Fernando G; Coutinho, Henrique Douglas M

2016-12-24

The use of popular plants has guided pharmaceutical research aimed at combating pathogenic microorganisms. Psidium guajava L. is a plant of great versatility and it has been used both as food and as a therapeutic agent. Root, bark, leaves, fruits, flowers and seeds are used for medicinal purposes, especially in infusions and decoctions for oral and topical use. P. guajava is utilized in symptomatology treatment related to organ malfunction and of diseases caused by the action of pathogenic and/or opportunistic microorganisms. Many pharmacological studies have been conducted to scientifically assess its therapeutic potential. The aim of the current study is to relate the popular use of this plant and its bioscientific assessment as a therapeutic agent in the treatment of diseases and symptoms caused by the action of protozoa, fungi, bacteria and viruses, and also evaluate the safety for the usage and the interaction with drugs. A bibliographic database the ethnobiology of Psidium guajava (2005-2015) and the pharmacological infections and parasitic diseases (2010-2015). Searches were done in scientific disclosure databases such as PubMed, Web of Science, and Scopus. P. guajava leaf extracts were scientifically investigated for the treatment of diseases caused by protozoa (leishmaniasis, malaria, giardiasis, amoebiasis and trichomoniasis), fungi (dermatosis, systemic and mucocutaneous diseases), bacteria (respiratory, mucocutaneous and gastrointestinal infections, cholera, gastritis and stomach ulcers, oral and periodontal infections, venereal diseases and urinary infections) and viruses (herpes, influenza, rotavirus disease and AIDS). The toxicity assays indicates the safet for usage. Highlight and elucidate the therapeutic potential and versatility of P. guajava. They also justify using ethnobiology efficiency to guide pharmacological studies. Some limitations can be observed in this kind of study, as the lack for ethnobiological informations and the absence of some controls in the assays. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

[Diversity of parasitic protozoan mitochondria and adaptive evolution].

PubMed

Tian, Hai-Feng; Wen, Jian-Fan

2010-02-01

Eukaryotic mitochondrion generally possess a definite and canonical structure and function. However, in the unicellular parasitic protozoa, various atypical mitochondria with respect to the number, structure, and function, have been discovered consecutively, revealing the variability, plasticity and rich diversity of mitochondrion. Here, we review the mitochondrial diversity in diverse parasitic protozoa, and the underlying reason for such diversity--the adaptive evolution of mitochondrion to the micro-oxygen or anaero parasitic environment of these parasites is also analyzed and discussed.

Protozoa in the diets of Neocalanus spp. in the oceanic subarctic Pacific Ocean

NASA Astrophysics Data System (ADS)

Gifford, Dian J.

Copepod species of the genus Neocalanus dominate the zooplankton biomass of the oceanic subarctic Pacific Ocean. Neocalanus spp. populations in the subarctic Pacific environment are successful: they feed, accumulate lipid, and persist from year to year. Prior experimental observations derived from a variety of methods indicated that, although their functional morphology is such that they clear the small phytoplankton cells characteristic of the oceanic subarctic Pacific environment efficiently, Neocalanus spp. do not consume sufficient phytoplankton to meet even basic metabolic requirements in that environment. Hence, their success in the subarctic Pacific must depend on their ability to obtain nutrition from other sources. As part of the SUPER ( SUbarctic Pacific Ecosystem Research) program, experiments were performed to test the hypothesis that N. plumchrus and N. cristatus obtain a significant portion of their nutrition from planktonic Protozoa. The experiments demonstrate that Protozoa alone do not provide sufficient nutrition for N. cristatus to meet its basic metabolic needs. Protozoa constitute the major dietary component of N. plumchrus however, in agreement with the predictions of FROST'S (1987) model of the subarctic Pacific ecosystem. At a minimum this diet permits N. plumchrus to meet basic metabolic requirements. Copepod grazing activities appear to be sufficient to control protozoan stocks in the oceanic subarctic Pacific during late spring and early summer when Neocalanus spp. inhabit the upper water column.

Enteric infections, diarrhea, and their impact on function and development

PubMed Central

Petri, William A.; Miller, Mark; Binder, Henry J.; Levine, Myron M.; Dillingham, Rebecca; Guerrant, Richard L.

2008-01-01

Enteric infections, with or without overt diarrhea, have profound effects on intestinal absorption, nutrition, and childhood development as well as on global mortality. Oral rehydration therapy has reduced the number of deaths from dehydration caused by infection with an enteric pathogen, but it has not changed the morbidity caused by such infections. This Review focuses on the interactions between enteric pathogens and human genetic determinants that alter intestinal function and inflammation and profoundly impair human health and development. We also discuss specific implications for novel approaches to interventions that are now opened by our rapidly growing molecular understanding. PMID:18382740

Massive Microbiological Groundwater Contamination Associated with a Waterborne Outbreak in Lake Erie, South Bass Island, Ohio

PubMed Central

Fong, Theng-Theng; Mansfield, Linda S.; Wilson, David L.; Schwab, David J.; Molloy, Stephanie L.; Rose, Joan B.

2007-01-01

Background A groundwater-associated outbreak affected approximately 1,450 residents and visitors of South Bass Island, Ohio, between July and September 2004. Objectives To examine the microbiological quality of groundwater wells located on South Bass Island, we sampled 16 wells that provide potable water to public water systems 15–21 September 2004. Methods We tested groundwater wells for fecal indicators, enteric viruses and bacteria, and protozoa (Cryptosporidium and Giardia). The hydrodynamics of Lake Erie were examined to explore the possible surface water–groundwater interactions. Results All wells were positive for both total coliform and Escherichia coli. Seven wells tested positive for enterococci and Arcobacter (an emerging bacterial pathogen), and F+-specific coliphage was present in four wells. Three wells were positive for all three bacterial indicators, coliphages, and Arcobacter; adenovirus DNA was recovered from two of these wells. We found a cluster of the most contaminated wells at the southeast side of the island. Conclusions Massive groundwater contamination on the island was likely caused by transport of microbiological contaminants from wastewater treatment facilities and septic tanks to the lake and the subsurface, after extreme precipitation events in May–July 2004. This likely raised the water table, saturated the subsurface, and along with very strong Lake Erie currents on 24 July, forced a surge in water levels and rapid surface water–groundwater interchange throughout the island. Landsat images showed massive influx of organic material and turbidity surrounding the island before the peak of the outbreak. These combinations of factors and information can be used to examine vulnerabilities in other coastal systems. Both wastewater and drinking water issues are now being addressed by the Ohio Environmental Protection Agency and the Ohio Department of Health. PMID:17589591

Prevalence and genetic diversity of norovirus among patients with acute diarrhea in Guatemala.

PubMed

Estévez, Alejandra; Arvelo, Wences; Hall, Aron J; López, María R; López, Beatriz; Reyes, Lissette; Moir, Juan Carlos; Gregoricus, Nicole; Vinjé, Jan; Parashar, Umesh D; Lindblade, Kim A

2013-07-01

Noroviruses (NoVs) are a leading cause of acute gastroenteritis outbreaks and sporadic cases of diarrhea in industrialized countries. To study the prevalence and genetic diversity of NoVs in Guatemala, stool specimens were collected from hospitalized and ambulatory patients presenting with diarrhea (≥3 loose or liquid stools in a 24-hr period) who were enrolled in a prospective surveillance system in the Departments of Santa Rosa (October 2007 to August 2010) and Quetzaltenango (August 2009 to August 2010), Guatemala. Specimens were tested for rotavirus, enteric bacteria, and parasites by routine methods and for genogroups I and II NoV by real-time reverse transcription-PCR. A total of 2,403 stool specimens were collected from hospitalized (n = 528) and ambulatory patients (n = 1,875). Overall, 341 (14%) samples tested positive for NoVs including 114 (22%) hospitalized and 227 (12%) ambulatory patients. NoVs disease peaked during the winter (November-January) months. Among the 341 NoVs-positive patients, 32 (9%) were also positive for rotavirus, 32 (9%) for bacteria, and 9 (3%) for protozoa. Nucleotide sequences were obtained from 84 samples collected from hospitalized children aged <5 years of age, which could be grouped into nine GII and three GI genotypes with GII.4 (74%) and GI.8 (10%) being the most common. This is the first study on the prevalence of NoVs among hospitalized and ambulatory patients with diarrhea in Guatemala. The findings highlight the need to implement laboratory diagnostics for NoVs to improve appropriate clinical management of diarrheal diseases and guide vaccine development. Copyright © 2013 Wiley Periodicals, Inc.

Intestinal parasites isolated in a large teaching hospital, Italy, 1 May 2006 to 31 December 2008.

PubMed

Masucci, L; Graffeo, R; Bani, S; Bugli, F; Boccia, S; Nicolotti, N; Fiori, B; Fadda, G; Spanu, T

2011-06-16

Intestinal parasites account for the majority of parasitic diseases, particularly in endemic areas. Most are transmitted via contaminated food. Because of increased immigration and travel, enteric parasitoses are now distributed worldwide. Between May 2006 and December 2008, we examined stool specimens from 5,351 patients (4,695 Italians, 656 non-Italians) for ova and parasites using microscopy, culture techniques, and molecular methods. Stools from 594 patients (11.1%) were contaminated and for all patients samples combined, a total of 700 intestinal parasites were counted. Ninety of the 594 infected patients had more than one parasite in their stools. Parasites causing intestinal disease occurred in 8.8% of patients. The prevalence was over twice as high among non-Italians (26.8% vs 8.9% in Italians, p<0.001) and higher in males (13.0% vs 9.5% in females, p=0.003). Most isolates were pathogenic protozoa, including in decreasing order of frequency: Blastocystis hominis, Giardia intestinalis, Entamoeba histolytica, and Cyclospora cayetanensis. The latter two species tended to be more common in Italians, although not at significant level (3.6% (15/418) vs 1.7% (3/176) in non-Italians, OR: 2.15; 95%CI: 0.60–11.70, p=0.22). Helminthes were found in 28 patients, mainly non-Italians (5.7% (10/176) vs 4.3% (18/418), OR: 1.34; 95%CI: 0.54–3.13, p=0.47). Ascaris lumbricoides and Hymenolepis nana were the most common. Strongyloides stercoralis, Enterobius vermicularis, Taenia spp. and Trichuris trichiura were also found. Intestinal parasites are a serious problem in developing countries, but should not be underestimated in industrialised countries.

Infection strategies of enteric pathogenic Escherichia coli

PubMed Central

Clements, Abigail; Young, Joanna C.; Constantinou, Nicholas; Frankel, Gad

2012-01-01

Enteric Escherichia coli (E. coli) are both natural flora of humans and important pathogens causing significant morbidity and mortality worldwide. Traditionally enteric E. coli have been divided into 6 pathotypes, with further pathotypes often proposed. In this review we suggest expansion of the enteric E. coli into 8 pathotypes to include the emerging pathotypes of adherent invasive E. coli (AIEC) and Shiga-toxin producing enteroaggregative E. coli (STEAEC). The molecular mechanisms that allow enteric E. coli to colonize and cause disease in the human host are examined and for two of the pathotypes that express a type 3 secretion system (T3SS) we discuss the complex interplay between translocated effectors and manipulation of host cell signaling pathways that occurs during infection. PMID:22555463

Effect of diet and absence of protozoa on the rumen microbial community and on the representativeness of bacterial fractions used in the determination of microbial protein synthesis.

PubMed

Belanche, A; de la Fuente, G; Pinloche, E; Newbold, C J; Balcells, J

2012-11-01

Accurate estimates of microbial synthesis in the rumen are vital to optimize ruminant nutrition. Liquid- (LAB) and solid-associated bacterial fractions (SAB) harvested from the rumen are generally considered as microbial references when microbial yield is calculated; however, factors that determine their composition are not completely understood. The aim of this study was to evaluate the effect of diet and absence or presence of rumen protozoa on the rumen microbial community. It was hypothesized that these treatments could modify the composition and representativeness of LAB and SAB. Twenty twin lambs (Ovis aries) were used; one-half of the twins were kept protozoa-free, and each respective twin sibling was faunated. At 6 mo of age, 5 animals from each group were randomly allocated to the experimental diets consisting of either alfalfa hay as the sole diet, or 50:50 mixed with ground barley grain. After 15 d of adaptation to the diet, animals were euthanized, rumen and abomasum contents were sampled, and LAB and SAB isolated. The presence of protozoa buffered the effect of diet on the rumen bacterial population. Faunated animals fed alfalfa hay had a greater abundance of F. succinogenes, anaerobic fungi and methanogens, as well as an enhanced rumen bacterial diversity. Cellulolytic bacteria were more abundant in SAB, whereas the abomasal abundance of most of the microorganisms studied was closer to those values observed in LAB. Rumen and abomasal samples showed similar bacterial DNA concentrations, but the fungal and protozoal DNA concentration in the abomasum was only 69% and 13% of that observed in the rumen, respectively, suggesting fungal and protozoal sequestration in the rumen or possible preferential degradation of fungal and protozoal DNA in the abomasum, or both. In conclusion, absence of protozoa and type of diet extensively modified the chemical composition of LAB and SAB as a consequence of changes in the microbial composition of these fractions.

Body-size spectra of biofilm-dwelling protozoa and their seasonal shift in coastal ecosystems.

PubMed

Zhao, Lu; Xu, Guangjian; Wang, Zheng; Xu, Henglong

2016-10-01

Community-based assessment of protozoa is usually performed at a taxon-dependent resolution. As an inherent 'taxon-free' trait, however, body-size spectrum has proved to be a highly informative indicator to summarize the functional structure of a community in both community research and monitoring programs in aquatic ecosystems. To demonstrate the relationships between the taxon-free resolution of protozoan communities and water conditions, the body-size spectra of biofilm-dwelling protozoa and their seasonal shift and environmental drivers were explored based on an annual dataset collected monthly from coastal waters of the Yellow Sea, northern China. Body sizes were calculated in equivalent spherical diameter (ESD). Among a total of 8 body-size ranks, S2 (19-27μm), S3 (28-36μm), S4 (37-50μm) and S5 (53-71μm) were the top four levels in frequency of occurrence, while rank S1 (13-17μm), S2 and S4 were the dominant levels in abundance. These dominants showed a clear seasonal succession: S2/S4 (spring)→S2/S4 (summer)→S4 (autumn)→S2 (winter) in frequency of occurrence; S1 (spring)→S4 (summer)→S2 (autumn)→S1 (winter) in abundance. Bootstrapped average analysis showed a clear seasonal shift in body-size spectra of the protozoa during a 1-year cycle, and the best-matching analysis demonstrated that the temporal variations in frequency of occurrence and abundance were significantly correlated with water temperature, pH, dissolved oxygen (DO), alone or in combination with chemical oxygen demand (COD) and nutrients. Thus, the body-size spectra of biofilm-dwelling protozoa were seasonally shaped and might be used as a time and cost efficient bioindicator of water quality in marine ecosystems. Copyright © 2016 Elsevier GmbH. All rights reserved.

Effects of hygiene and defecation behavior on helminths and intestinal protozoa infections in Taabo, Côte d'Ivoire.

PubMed

Schmidlin, Thomas; Hürlimann, Eveline; Silué, Kigbafori D; Yapi, Richard B; Houngbedji, Clarisse; Kouadio, Bernadette A; Acka-Douabélé, Cinthia A; Kouassi, Dongo; Ouattara, Mamadou; Zouzou, Fabien; Bonfoh, Bassirou; N'Goran, Eliézer K; Utzinger, Jürg; Raso, Giovanna

2013-01-01

More than 1 billion people are currently infected with soil-transmitted helminths and schistosomes. The global strategy to control helminthiases is the regular administration of anthelmintic drugs to at-risk populations. However, rapid re-infection occurs in areas where hygiene, access to clean water, and sanitation are inadequate. In July 2011, inhabitants from two villages and seven hamlets of the Taabo health demographic surveillance system in south-central Côte d'Ivoire provided stool and urine samples. Kato-Katz and ether-concentration methods were used for the diagnosis of Schistosoma mansoni, soil-transmitted helminths (Ascaris lumbricoides, Trichuris trichiura, and hookworm), and intestinal protozoa. Urine samples were subjected to a filtration method for the diagnosis of Schistosoma haematobium. A questionnaire was administered to households to obtain information on knowledge, attitude, practice, and beliefs in relation to hygiene, sanitation, and defecation behavior. Logistic regression models were employed to assess for associations between questionnaire data and parasitic infections. A total of 1,894 participants had complete data records. Parasitological examinations revealed prevalences of hookworm, S. haematobium, T. trichiura, S. mansoni, and A. lumbricoides of 33.5%, 7.0%, 1.6%, 1.3% and 0.8%, respectively. Giardia intestinalis and Entamoeba histolytica/E. dispar were detected in 15.0% and 14.4% of the participants, respectively. Only one out of five households reported the presence of a latrine, and hence, open defecation was common. Logistic regression analysis revealed that age, sex, socioeconomic status, hygiene, and defecation behavior are determinants for helminths and intestinal protozoa infections. We found that inadequate sanitation and hygiene behavior are associated with soil-transmitted helminths and intestinal protozoa infections in the Taabo area of south-central Côte d'Ivoire. Our data will serve as a benchmark to monitor the effect of community-led total sanitation and hygiene education to reduce the transmission of helminthiases and intestinal protozoa infections.

Effects of Hygiene and Defecation Behavior on Helminths and Intestinal Protozoa Infections in Taabo, Côte d’Ivoire

PubMed Central

Schmidlin, Thomas; Hürlimann, Eveline; Silué, Kigbafori D.; Yapi, Richard B.; Houngbedji, Clarisse; Kouadio, Bernadette A.; Acka-Douabélé, Cinthia A.; Kouassi, Dongo; Ouattara, Mamadou; Zouzou, Fabien; Bonfoh, Bassirou; N’Goran, Eliézer K.; Utzinger, Jürg; Raso, Giovanna

2013-01-01

Background More than 1 billion people are currently infected with soil-transmitted helminths and schistosomes. The global strategy to control helminthiases is the regular administration of anthelmintic drugs to at-risk populations. However, rapid re-infection occurs in areas where hygiene, access to clean water, and sanitation are inadequate. Methodology In July 2011, inhabitants from two villages and seven hamlets of the Taabo health demographic surveillance system in south-central Côte d’Ivoire provided stool and urine samples. Kato-Katz and ether-concentration methods were used for the diagnosis of Schistosoma mansoni, soil-transmitted helminths (Ascaris lumbricoides, Trichuris trichiura, and hookworm), and intestinal protozoa. Urine samples were subjected to a filtration method for the diagnosis of Schistosoma haematobium. A questionnaire was administered to households to obtain information on knowledge, attitude, practice, and beliefs in relation to hygiene, sanitation, and defecation behavior. Logistic regression models were employed to assess for associations between questionnaire data and parasitic infections. Principal Findings A total of 1,894 participants had complete data records. Parasitological examinations revealed prevalences of hookworm, S. haematobium, T. trichiura, S. mansoni, and A. lumbricoides of 33.5%, 7.0%, 1.6%, 1.3% and 0.8%, respectively. Giardia intestinalis and Entamoeba histolytica/E. dispar were detected in 15.0% and 14.4% of the participants, respectively. Only one out of five households reported the presence of a latrine, and hence, open defecation was common. Logistic regression analysis revealed that age, sex, socioeconomic status, hygiene, and defecation behavior are determinants for helminths and intestinal protozoa infections. Conclusions/Significance We found that inadequate sanitation and hygiene behavior are associated with soil-transmitted helminths and intestinal protozoa infections in the Taabo area of south-central Côte d’Ivoire. Our data will serve as a benchmark to monitor the effect of community-led total sanitation and hygiene education to reduce the transmission of helminthiases and intestinal protozoa infections. PMID:23840358

Water quality bioassay using selected protozoa. I. [Paramecium candatum; Amoeba proteus; Euglena gracilis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mills, W.L.

1976-01-01

The suitability of certain species of protozoa as indicators of water quality has been determined. Experiments were conducted under laboratory conditions to standardize a bioassay procedure for water quality using either Paramecium caudatum, Amoeba proteus, or Euglena gracilis as the indicator organism. The bioassay, which consists of exposing the organisms to a known concentration of pollutant under laboratory conditions, followed by microscopic observation to establish the time of death, affords a reliable, convenient and inexpensive way to monitor for water quality.

Observations on the intestinal protozoa infecting man in Rhodesia.

PubMed

Goldsmid, J M; Rogers, S; Mahomed, K

1976-09-18

Humans in Rhodesia harbour a wide range of intestinal protozoa. Of the species included, Entamoeba histolytica, Entamoeba coli and Giardia lamblia have previously been recorded. Other species which are either rarely reported or which have previously never been reported from this country, include Trichomonas hominis, Chilomastix mesnili, Enteromonas hominis, Retortamonas intestinalis, Balantidum coli,Entamoeba hartmanni,Entamoeba histolytica Laredo. Endolimax nana, Dientamoeba fragilis and Isospora belli. The importance in Rhodesia of these species, and especially of E. histolytica, is discussed.

Assessing the health status of farmed mussels (Mytilus galloprovincialis) through histological, microbiological and biomarker analyses.

PubMed

Matozzo, Valerio; Ercolini, Carlo; Serracca, Laura; Battistini, Roberta; Rossini, Irene; Granato, Giulia; Quaglieri, Elisabetta; Perolo, Alberto; Finos, Livio; Arcangeli, Giuseppe; Bertotto, Daniela; Radaelli, Giuseppe; Chollet, Bruno; Arzul, Isabelle; Quaglio, Francesco

2018-03-01

The Gulf of La Spezia (northern Tyrrhenian Sea, Italy) is a commercially important area both as a shipping port and for mussel farming. Recently, there has been increased concern over environmental disturbances caused by anthropogenic activities such as ship traffic and dredging and the effects they have on the health of farmed mussels. This paper reports the results of microbiological and histological analyses, as well as of measurement of several biomarkers which were performed to assess the health status of mussels (Mytilus galloprovincialis) from four rearing sites in the Gulf of La Spezia. Mussels were collected between October 2015 and September 2016 and histological analyses (including gonadal maturation stage), as well as the presence of pathogenic bacteria (Vibrio splendidus clade, V. aestuarianus and V. harveyi), viruses (Herpes virus and ostreid Herpes virus 1) and protozoa (Marteilia spp., in the summer season only) were carried out on a monthly basis. Conversely, biomarker responses in haemocyte/haemolymph (total haemocyte count, haemocyte diameter and volume, lysozyme and lactate dehydrogenase activities in cell-free haemolymph, and micronuclei frequency) and in gills and digestive gland (cortisol-like steroids and lipid peroxidation levels), were evaluated bimonthly. Microbiological data indicated that mussels contain a reservoir of potentially pathogenic bacteria, viruses and protozoa that in certain environmental conditions may cause a weakening of the immune system of animals leading to mortality episodes. The percentage of parasites detected in the mussels was generally low (9.6% for Steinhausia mytilovum, that is 17 samples out of 177 examined females; 3.4% for Proctoeces maculatus; 0.9% for Mytilicola intestinalis and 2% for ciliated protozoa), while symbiont loads were higher (31% for Eugymnanthea inquilina and Urastoma cyprinae). Interestingly, a previously undescribed haplosporidian was detected in a single mussel sample (0.2%) and was confirmed by in situ hybridization. Cells morphologically similar to Perkinsus sp. trophozoites were observed in 0.7% of the mussels analysed; however, infection with Perkinsus spp. could neither be confirmed by ISH nor by PCR. Different pathological aspects, such as host defence responses and regressive/progressive changes were detected in the gills, digestive glands, gonads and mantle. Only one single case of disseminated neoplasia (0.2%) was observed. As for the biomarker evaluation, the MANOVA analysis revealed the statistically significant effect that the variable "sampling site" had on the biological parameter measured, thus suggesting that the multibiomarker approach was able to differentiate the rearing sites. Copyright © 2018 Elsevier Inc. All rights reserved.

21 CFR 520.2158a - Streptomycin sulfate oral solution.

Code of Federal Regulations, 2012 CFR

2012-04-01

...) Indications for use. Treatment of bacterial enteritis caused by Escherichia coli and Salmonella spp... streptomycin. Consult a veterinarian or animal pathologist for diagnosis. (2) Chickens—(i) Amount. 10 to 15 mg... infectious enteritis caused by organisms susceptible to streptomycin. (iii) Limitations. Chickens: Do not...

21 CFR 520.2158a - Streptomycin sulfate oral solution.

Code of Federal Regulations, 2013 CFR

2013-04-01

...) Indications for use. Treatment of bacterial enteritis caused by Escherichia coli and Salmonella spp... streptomycin. Consult a veterinarian or animal pathologist for diagnosis. (2) Chickens—(i) Amount. 10 to 15 mg... infectious enteritis caused by organisms susceptible to streptomycin. (iii) Limitations. Chickens: Do not...

21 CFR 520.2158a - Streptomycin sulfate oral solution.

Code of Federal Regulations, 2014 CFR

2014-04-01

...) Indications for use. Treatment of bacterial enteritis caused by Escherichia coli and Salmonella spp... streptomycin. Consult a veterinarian or animal pathologist for diagnosis. (2) Chickens—(i) Amount. 10 to 15 mg... infectious enteritis caused by organisms susceptible to streptomycin. (iii) Limitations. Chickens: Do not...

Protozoan grazing reduces the current output of microbial fuel cells.

PubMed

Holmes, Dawn E; Nevin, Kelly P; Snoeyenbos-West, Oona L; Woodard, Trevor L; Strickland, Justin N; Lovley, Derek R

2015-10-01

Several experiments were conducted to determine whether protozoan grazing can reduce current output from sediment microbial fuel cells. When marine sediments were amended with eukaryotic inhibitors, the power output from the fuel cells increased 2-5-fold. Quantitative PCR showed that Geobacteraceae sequences were 120 times more abundant on anodes from treated fuel cells compared to untreated fuel cells, and that Spirotrichea sequences in untreated fuel cells were 200 times more abundant on anode surfaces than in the surrounding sediments. Defined studies with current-producing biofilms of Geobacter sulfurreducens and pure cultures of protozoa demonstrated that protozoa that were effective in consuming G. sulfurreducens reduced current production up to 91% when added to G. sulfurreducens fuel cells. These results suggest that anode biofilms are an attractive food source for protozoa and that protozoan grazing can be an important factor limiting the current output of sediment microbial fuel cells. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

[Intestinal parasitic diseases as a global health problem].

PubMed

Chacín-Bonilla, Leonor

2013-03-01

In today's world, parasitic disease agents are not restricted by geography or economy, and have become a significant global threat. The increasing globalization of the fresh produce market and greater international trade and travels, have contributed to the spread of these organisms in the industrialized world. Parasitic protozoa cause waterborne and foodborne outbreaks of diarrhea. The unprecedented flow of people introduces cultural and behavior patterns around the world; the increasing tendency to eat raw or undercooked meat and seafood, favors the dissemination of several parasitic pathogens. Climate changes are predicted to cause a global increase in soil-transmitted helminthiases. The multidisciplinary study of these agents, and the interaction among scientists, global health organizations and governments are imperative to reduce the burden of these diseases and improve the life of a large segment of the world population.

The fossil tabanids (Diptera Tabanidae): when they began to appreciate warm blood and when they began transmit diseases?

PubMed

Martins-Neto, Rafael Gioia

2003-01-01

A discussion of the known fossil tabanids (Diptera Tabanidae) is presented based on fossil evidence. This includes the origin of the hemathophagy in the Brachycera, more specifically for tabanids. Several tabanid species in the extant fauna are vectors for disease-producing organisms that affect humans and animals. Bacteria, viruses, rickettsiae, protozoa, and filarial worms can be transmitted by them, causing such diseases as anthrax, tularemia, anaplasmosis, various forms of trypanosomiasis, Q fever, and filariasis. However, if tabanids are directly responsible for all of these diseases is not consensual and the known fossil evidence is presented here.

21 CFR 558.128 - Chlortetracycline.

Code of Federal Regulations, 2011 CFR

2011-04-01

..., 046573, 048164, 066104. (iv) 500 g/ton Chickens: For the reduction of mortality due to E. coli infections... weight 1. Swine: For the treatment of bacterial enteritis caused by E. coli and S. choleraesuis and.... Calves, beef and nonlactating dairy cattle; treatment of bacterial enteritis caused by E. coli and...

21 CFR 520.445c - Chlortetracycline tablets and boluses.

Code of Federal Regulations, 2011 CFR

2011-04-01

... enteritis (scours) caused by E. coli and Salmonella spp. and bacterial pneumonia associated with Pasteurella... 5 days. (i) Indications for use. Treatment of bacterial enteritis (scours) caused by E. coli and... chapter but may require bioequivalency and safety information. (e) Conditions of use. Calves—(1) Amount...

21 CFR 558.128 - Chlortetracycline.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., 046573, 048164, 066104. (iv) 500 g/ton Chickens: For the reduction of mortality due to E. coli infections... weight 1. Swine: For the treatment of bacterial enteritis caused by E. coli and S. choleraesuis and.... Calves, beef and nonlactating dairy cattle; treatment of bacterial enteritis caused by E. coli and...

21 CFR 520.445c - Chlortetracycline tablets and boluses.

Code of Federal Regulations, 2010 CFR

2010-04-01

... enteritis (scours) caused by E. coli and Salmonella spp. and bacterial pneumonia associated with Pasteurella... 5 days. (i) Indications for use. Treatment of bacterial enteritis (scours) caused by E. coli and... chapter but may require bioequivalency and safety information. (e) Conditions of use. Calves—(1) Amount...

RNA in development: how ribonucleoprotein granules regulate the life cycles of pathogenic protozoa.

PubMed

Kramer, Susanne

2014-01-01

Ribonucleoprotein (RNP) granules are important posttranscriptional regulators of messenger RNA (mRNA) fate. Several types of RNP granules specifically regulate gene expression during development of multicellular organisms and are commonly referred to as germ granules. The function of germ granules is not entirely understood and probably diverse, but it is generally agreed that one main function is posttranscriptional regulation of gene expression during early development, when transcription is silent. One example is the translational repression of maternally derived mRNAs in oocytes. Here, I hope to show that the need for regulation of gene expression by RNP granules is not restricted to animal development, but plays an equally important role during the development of pathogenic protozoa. Apicomplexa and Trypanosomatidae have complex life cycles with frequent host changes. The need to quickly adapt gene expression to a new environment as well as the ability to suppress translation to survive latencies is critical for successful completion of life cycles. Posttranscriptional gene regulation is not necessarily simpler in protozoa. Apicomplexa surprise with the presence of micro RNA (miRNAs) and upstream open reading frames (µORFs). Trypanosomes have an unusually large repertoire of different RNP granule types. A better understanding of RNP granules in protozoa may help to gain insight into the evolutionary origin of RNP granules: Trypanosomes for example have two types of granules with interesting similarities to animal germ granules. © 2013 John Wiley & Sons, Ltd.

Microscopic and molecular studies of the diversity of free-living protozoa in meat-cutting plants.

PubMed

Vaerewijck, Mario J M; Sabbe, Koen; Baré, Julie; Houf, Kurt

2008-09-01

The diversity of free-living protozoa in five meat-cutting plants was determined. Light microscopy after enrichment culturing was combined with sequencing of PCR-amplified, denaturing gradient gel electrophoresis (DGGE)-separated 18S rRNA gene fragments, which was used as a fast screening method. The general results of the survey showed that a protozoan community of amoebae, ciliates, and flagellates was present in all of the plants. Protozoa were detected mainly in floor drains, in standing water on the floor, on soiled bars of cutting tables, on plastic pallets, and in out-of-use hot water knife sanitizers, but they were also detected on surfaces which come into direct contact with meat, such as conveyer belts, working surfaces of cutting tables, and needles of a meat tenderizer. After 7 days of incubation at refrigerator temperature, protozoa were detected in about one-half of the enrichment cultures. Based on microscopic observations, 61 morphospecies were found, and Bodo saltans, Bodo spp., Epistylis spp., Glaucoma scintillans, Petalomonas spp., Prodiscophrya collini, and Vannella sp. were the most frequently encountered identified organisms. Sequencing of DGGE bands resulted in identification of a total of 49 phylotypes, including representatives of the Amoebozoa, Chromalveolata, Excavata, Opisthokonta, and Rhizaria. Sequences of small heterotrophic flagellates were affiliated mainly with the Alveolata (Apicomplexa), Stramenopiles (Chrysophyceae), and Rhizaria (Cercozoa). This survey showed that there is high protozoan species richness in meat-cutting plants and that the species included species related to known hosts of food-borne pathogens.

Prevalence of protozoa, viruses, coliphages and indicator bacteria in groundwater and river water in the Kathmandu Valley, Nepal.

PubMed

Haramoto, Eiji; Yamada, Kaoru; Nishida, Kei

2011-12-01

Limited information is available on the prevalence of waterborne pathogens in aquatic environments in developing countries. In this study, water samples were collected from nine shallow wells and a river in the Kathmandu Valley, Nepal, during the rainy season in 2009 and were subjected to detection of waterborne protozoa, viruses and coliphages using a recently developed method for simultaneous concentration of protozoa and viruses in water. Escherichia coli and total coliforms were also tested as indicator bacteria. At least one type of the five pathogens tested (Cryptosporidium, Giardia, human adenoviruses, and noroviruses of genogroups I and II) was detected in five groundwater samples (56%) (1000 ml each) from shallow wells. Compared with groundwater samples, the pathogens were more abundant in the river water sample (100ml); the concentrations of Cryptosporidium and Giardia were 140 oocysts/l and 8500 cysts/l, respectively, and the mean threshold cycle (Ct) values in real-time RT-PCR were 34.3, 36.8 and 34.0 for human adenoviruses and noroviruses of genogroups I and II, respectively. Genotyping of F-RNA coliphages by real-time RT-PCR was successfully used to differentiate human and animal faecal contamination in the samples. Moreover, for the groundwater samples, protozoa and viruses were detected only in E. coli-positive samples, suggesting that E. coli may be an appropriate indicator of pathogen contamination of valley groundwater. Copyright © 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

The role of Legionella pneumophila-infected Hartmannella vermiformis as an infectious particle in a murine model of Legionnaire's disease.

PubMed

Brieland, J K; Fantone, J C; Remick, D G; LeGendre, M; McClain, M; Engleberg, N C

1997-12-01

Legionella pneumophila is a bacterial parasite of many species of freshwater protozoa and occasionally an intracellular pathogen of humans. While protozoa are known to play a key role in the persistence of L. pneumophila in the environment, there has been limited research addressing the potential role of L. pneumophila-infected protozoa in the pathogenesis of human infection. In this report, the potential role of an L. pneumophila-infected amoeba as an infectious particle in replicative L. pneumophila lung infection was investigated in vivo with the amoeba Hartmannella vermiformis, a natural reservoir of L. pneumophila in the environment. L. pneumophila-infected H. vermiformis organisms were prepared by coculture of the amoebae and virulent L. pneumophila cells in vitro. A/J mice, which are susceptible to replicative L. pneumophila lung infection, were subsequently inoculated intratracheally with L. pneumophila-infected H. vermiformis organisms (10(6) amoebae containing 10(5) bacteria), and intrapulmonary growth of the bacteria was assessed. A/J mice inoculated intratracheally with L. pneumophila-infected H. vermiformis organisms developed replicative L. pneumophila lung infections. Furthermore, L. pneumophila-infected H. vermiformis organisms were more pathogenic than an equivalent number of bacteria or a coinoculum of L. pneumophila cells and uninfected amoebae. These results demonstrate that L. pneumophila-infected amoebae are infectious particles in replicative L. pneumophila infections in vivo and support the hypothesis that inhaled protozoa may serve as cofactors in the pathogenesis of pulmonary disease induced by inhaled respiratory pathogens.

Genome mining offers a new starting point for parasitology research.

PubMed

Lv, Zhiyue; Wu, Zhongdao; Zhang, Limei; Ji, Pengyu; Cai, Yifeng; Luo, Shiqi; Wang, Hongxi; Li, Hao

2015-02-01

Parasites including helminthes, protozoa, and medical arthropod vectors are a major cause of global infectious diseases, affecting one-sixth of the world's population, which are responsible for enormous levels of morbidity and mortality important and remain impediments to economic development especially in tropical countries. Prevalent drug resistance, lack of highly effective and practical vaccines, as well as specific and sensitive diagnostic markers are proving to be challenging problems in parasitic disease control in most parts of the world. The impressive progress recently made in genome-wide analysis of parasites of medical importance, including trematodes of Clonorchis sinensis, Opisthorchis viverrini, Schistosoma haematobium, S. japonicum, and S. mansoni; nematodes of Brugia malayi, Loa loa, Necator americanus, Trichinella spiralis, and Trichuris suis; cestodes of Echinococcus granulosus, E. multilocularis, and Taenia solium; protozoa of Babesia bovis, B. microti, Cryptosporidium hominis, Eimeria falciformis, E. histolytica, Giardia intestinalis, Leishmania braziliensis, L. donovani, L. major, Plasmodium falciparum, P. vivax, Trichomonas vaginalis, Trypanosoma brucei and T. cruzi; and medical arthropod vectors of Aedes aegypti, Anopheles darlingi, A. sinensis, and Culex quinquefasciatus, have been systematically covered in this review for a comprehensive understanding of the genetic information contained in nuclear, mitochondrial, kinetoplast, plastid, or endosymbiotic bacterial genomes of parasites, further valuable insight into parasite-host interactions and development of promising novel drug and vaccine candidates and preferable diagnostic tools, thereby underpinning the prevention and control of parasitic diseases.

The role of wild canids and felids in spreading parasites to dogs and cats in Europe. Part I: Protozoa and tick-borne agents.

PubMed

Otranto, Domenico; Cantacessi, Cinzia; Pfeffer, Martin; Dantas-Torres, Filipe; Brianti, Emanuele; Deplazes, Peter; Genchi, Claudio; Guberti, Vittorio; Capelli, Gioia

2015-09-30

Over the last few decades, the world has witnessed radical changes in climate, landscape, and ecosystems. These events, together with other factors such as increasing illegal wildlife trade and changing human behaviour towards wildlife, are resulting into thinning boundaries between wild canids and felids and their domestic counterparts. As a consequence, the epidemiology of diseases caused by a number of infectious agents is undergoing profound readjustements, as pathogens adapt to new hosts and environments. Therefore, there is a risk for diseases of wildlife to spread to domestic carnivores and vice versa, and for zoonotic agents to emerge or re-emerge in human populations. Hence, the identification of the hazards arising from the co-habitation of these species is critical in order to plan and develop adequate control strategies against these pathogens. In the first of this two-part article, we review the role that wild canids and felids may play in the transmission of protozoa and arthropod-borne agents to dogs and cats in Europe, and provide an account of how current and future progress in our understanding of the ecology and epidemiology of parasites, as well as of host-parasite interactions, can assist efforts aimed at controlling parasite transmission. Copyright © 2015 Elsevier B.V. All rights reserved.

Webuye Health and Demographic Surveillance Systems Baseline Survey of Soil-Transmitted Helminths and Intestinal Protozoa among Children up to Five Years

PubMed Central

Obala, A. A.; Simiyu, C. J.; Odhiambo, D. O.; Nanyu, V.; Chege, P.; Downing, R.; Mwaliko, E.; Mwangi, A. W.; Menya, D.; Chelagat, D.; Nyamogoba, H. D. N.; Ayuo, P. O.; O'Meara, W. P.; Twagirumukiza, M.; Vandenbroek, D.; Otsyula, B. B. O.; de Maeseneer, J.

2013-01-01

Background. The intestinal parasitic infections (IPIs) are globally endemic, and they constitute the greatest cause of illness and disease worldwide. Transmission of IPIs occurs as a result of inadequate sanitation, inaccessibility to potable water, and poor living conditions. Objectives. To determine a baseline prevalence of IPIs among children of five years and below at Webuye Health and Demographic Surveillance (HDSS) area in western Kenya. Methods. Cross-sectional survey was used to collect data. Direct saline and formal-ether-sedimentation techniques were used to process the specimens. Descriptive and inferential statistics such as Chi-square statistics were used to analyze the data. Results. A prevalence of 52.3% (417/797) was obtained with the male child slightly more infected than the female (53.5% versus 51%), but this was not significant (χ 2 = 0.482, P > 0.05). Giardia lamblia and Entamoeba histolytica were the most common pathogenic IPIs with a prevalence of 26.1% (208/797) and 11.2% (89/797), respectively. Soil-transmitted helminths (STHs) were less common with a prevalence of 4.8% (38/797), 3.8% (30/797), and 0.13% (1/797) for Ascaris lumbricoides, hookworms, and Trichuris trichiura, respectively. Conclusions. Giardia lamblia and E. histolytica were the most prevalent pathogenic intestinal protozoa, while STHs were less common. Community-based health promotion techniques are recommended for controlling these parasites. PMID:23533444

Influence of Rack Design and Disease Prevalence on Detection of Rodent Pathogens in Exhaust Debris Samples from Individually Ventilated Caging Systems.

PubMed

Bauer, Beth A; Besch-Williford, Cynthia; Livingston, Robert S; Crim, Marcus J; Riley, Lela K; Myles, Matthew H

2016-11-01

Sampling of bedding debris within the exhaust systems of ventilated racks may be a mechanism for detecting murine pathogens in colony animals. This study examined the effectiveness of detecting pathogens by PCR analysis of exhaust debris samples collected from ventilated racks of 2 different rack designs, one with unfiltered air flow from within the cage to the air-exhaust pathway, and the other had a filter between the cage and the air-exhaust pathway. For 12 wk, racks were populated with either 1 or 5 cages of mice (3 mice per cage) infected with one of the following pathogens: mouse norovirus (MNV), mouse parvovirus (MPV), mouse hepatitis virus (MHV), Helicobacter spp., Pasteurella pneumotropica, pinworms, Entamoeba muris, Tritrichomonas muris, and fur mites. Pathogen shedding by infected mice was monitored throughout the study. In the filter-containing rack, PCR testing of exhaust plenums yielded negative results for all pathogens at all time points of the study. In the rack with open air flow, pathogens detected by PCR analysis of exhaust debris included MHV, Helicobacter spp., P. pneumotropica, pinworms, enteric protozoa, and fur mites; these pathogens were detected in racks housing either 1 or 5 cages of infected mice. Neither MPV nor MNV was detected in exhaust debris, even though prolonged viral shedding was confirmed. These results demonstrate that testing rack exhaust debris from racks with unfiltered air flow detected MHV, enteric bacteria and parasites, and fur mites. However, this method failed to reliably detect MNV or MPV infection of colony animals.

Influence of Rack Design and Disease Prevalence on Detection of Rodent Pathogens in Exhaust Debris Samples from Individually Ventilated Caging Systems

PubMed Central

Bauer, Beth A; Besch-Williford, Cynthia; Livingston, Robert S; Crim, Marcus J; Riley, Lela K; Myles, Matthew H

2016-01-01

Sampling of bedding debris within the exhaust systems of ventilated racks may be a mechanism for detecting murine pathogens in colony animals. This study examined the effectiveness of detecting pathogens by PCR analysis of exhaust debris samples collected from ventilated racks of 2 different rack designs, one with unfiltered air flow from within the cage to the air-exhaust pathway, and the other had a filter between the cage and the air-exhaust pathway. For 12 wk, racks were populated with either 1 or 5 cages of mice (3 mice per cage) infected with one of the following pathogens: mouse norovirus (MNV), mouse parvovirus (MPV), mouse hepatitis virus (MHV), Helicobacter spp., Pasteurella pneumotropica, pinworms, Entamoeba muris, Tritrichomonas muris, and fur mites. Pathogen shedding by infected mice was monitored throughout the study. In the filter-containing rack, PCR testing of exhaust plenums yielded negative results for all pathogens at all time points of the study. In the rack with open air flow, pathogens detected by PCR analysis of exhaust debris included MHV, Helicobacter spp., P. pneumotropica, pinworms, enteric protozoa, and fur mites; these pathogens were detected in racks housing either 1 or 5 cages of infected mice. Neither MPV nor MNV was detected in exhaust debris, even though prolonged viral shedding was confirmed. These results demonstrate that testing rack exhaust debris from racks with unfiltered air flow detected MHV, enteric bacteria and parasites, and fur mites. However, this method failed to reliably detect MNV or MPV infection of colony animals. PMID:27931317

Tea saponin reduced methanogenesis in vitro but increased methane yield in lactating dairy cows.

PubMed

Guyader, J; Eugène, M; Doreau, M; Morgavi, D P; Gérard, C; Martin, C

2017-03-01

The effect of tea saponin supplementation in the ruminant diet on methane emissions, rumen fermentation, and digestive processes is still under debate. The objective of this study was to assess the effect of this plant extract on methanogenesis, total-tract digestibility, and lactating performances of dairy cows. The work included 2 independent and successive experiments. First, the effect of 7 tea saponin doses (from 0 to 0.50 g/L) on methane emissions and protozoa concentrations was tested in 2 repeated in vitro batch culture incubations using bovine rumen contents as inoculum and a cereal mixture as substrate. After 18 h of incubation, total gas production and composition as well as rumen fermentation parameters and protozoa concentration were analyzed. Increasing dosage of the plant extract reduced methane production and protozoa concentration, with a maximum reduction of 29% for CH 4 (mL/g of substrate) and 51% for protozoa (10 5 /mL). Tea saponin did not affect volatile fatty acids concentration, but marginally decreased total gas production by 5% at the highest dose. Second, a 2-period crossover design experiment was carried out with 8 lactating dairy cows fed a basal diet (54% corn silage, 6% hay, and 40% pelleted concentrates on a dry matter basis) without (control) or with 0.52% tea saponin (TSP). Each experimental period lasted 5 wk. Animals were fed ad libitum during the first 3 wk of the period (wk 1, 2, and 3) and restricted (95% of ad libitum intake) during the last 2 wk (wk 4 and 5). Intake and milk production were recorded daily. Methane emissions were quantified using open chambers (2 d, wk 4). Total-tract digestibility and nitrogen balance were determined from total feces and urine collected separately (5 d, wk 5). Rumen fermentation parameters and protozoa concentration were analyzed from samples taken after morning feeding (1 d, wk 5). Milk production, dry matter intake, and feed efficiency were reduced with TSP (-18, -12, and -8%, respectively). As daily methane production (g/d) was not affected, methane emissions (g/kg of dry matter intake) increased by 14% with TSP. Total-tract digestibility and nitrogen balance were similar between diets, except for acid detergent fiber digestibility, which tended to be improved with TSP (+4 percentage units). Rumen fermentation parameters and protozoa concentration were relatively unchanged by diets. Under the conditions of this experiment, tea saponin is not efficient to reduce methane emissions from dairy cows. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Inactivation of Giardia Cysts by Iodine with Special Reference to Globaline: A Review

DTIC Science & Technology

1991-04-01

different forms of iodine to destroy Giardia cysts ......••••....•......•......•• 11 2. Destruction of protozoa cysts by Globaline at variO\\ls t ~atures...water at J 0 e and 20~e • • • • 13 4. Destruction of protozoa cysts by elenEntal iodine . . . 14 5. Destruction of Giardia cysts (1000/mL) by t -wo...tablet, which had been used since World War I for disinfecting canteen water ( 14) • A research and development program was sponsored by the Army

Fluorogenic Substrate Detection of Viable Intracellular and Extracellular Pathogenic Protozoa

NASA Astrophysics Data System (ADS)

Jackson, Peter R.; Pappas, Michael G.; Hansen, Brian D.

1985-01-01

Viable Leishmania promastigotes and amastigotes were detected by epifluorescence microscopy with fluorescein diacetate being used to mark living parasites and the nucleic acid-binding compound ethidium bromide to stain dead cells. This procedure is superior to other assays because it is faster and detects viable intracellular as well as extracellular Leishmania. Furthermore, destruction of intracellular pathogens by macrophages is more accurately determined with fluorescein diacetate than with other stains. The procedure may have applications in programs to develop drugs and vaccines against protozoa responsible for human and animal disease.

Age-dependent shift in macrophage polarisation causes inflammation-mediated degeneration of enteric nervous system.

PubMed

Becker, Laren; Nguyen, Linh; Gill, Jaspreet; Kulkarni, Subhash; Pasricha, Pankaj Jay; Habtezion, Aida

2018-05-01

The enteric nervous system (ENS) undergoes neuronal loss and degenerative changes with age. The cause of this neurodegeneration is poorly understood. Muscularis macrophages residing in close proximity to enteric ganglia maintain neuromuscular function via direct crosstalk with enteric neurons and have been implicated in the pathogenesis of GI motility disorders like gastroparesis and postoperative ileus. The aim of this study was to assess whether ageing causes alterations in macrophage phenotype that contributes to age-related degeneration of the ENS. Longitudinal muscle and myenteric plexus from small intestine of young, mid-aged and old mice were dissected and prepared for whole mount immunostaining, flow cytometry, Luminex immunoassays, western blot analysis, enteric neural stem cell (ENSC) isolation or conditioned media. Bone marrow derived macrophages were prepared and polarised to classic (M1) or alternative (M2) activation states. Markers for macrophage phenotype were measured using quantitative RT-PCR. Ageing causes a shift in macrophage polarisation from anti-inflammatory 'M2' to proinflammatory 'M1' that is associated with a rise in cytokines and immune cells in the ENS. This phenotypic shift is associated with a neural response to inflammatory signals, increase in apoptosis and loss of enteric neurons and ENSCs, and delayed intestinal transit. An age-dependent decrease in expression of the transcription factor FoxO3, a known longevity gene, contributes to the loss of anti-inflammatory behaviour in macrophages of old mice, and FoxO3-deficient mice demonstrate signs of premature ageing of the ENS. A shift by macrophages towards a proinflammatory phenotype with ageing causes inflammation-mediated degeneration of the ENS. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Molecular characterization of intestinal protozoa in two poor communities in the State of São Paulo, Brazil.

PubMed

David, Érica Boarato; Guimarães, Semíramis; de Oliveira, Ana Paula; Goulart de Oliveira-Sequeira, Teresa Cristina; Nogueira Bittencourt, Gabriela; Moraes Nardi, Ana Rita; Martins Ribolla, Paulo Eduardo; Bueno Franco, Regina Maura; Branco, Nilson; Tosini, Fabio; Bella, Antonino; Pozio, Edoardo; Cacciò, Simone M

2015-02-15

Several species of protozoa cause acute or chronic gastroenteritis in humans, worldwide. The burden of disease is particularly high among children living in developing areas of the world, where transmission is favored by lower hygienic standards and scarce availability of safe water. However, asymptomatic infection and polyparasitism are also commonly observed in poor settings. Here, we investigated the prevalence of intestinal protozoa in two small fishing villages, Porto Said (PS) and Santa Maria da Serra (SM), situated along the river Tietê in the State of São Paolo, Brazil. The villages lack basic public infrastructure and services, such as roads, public water supply, electricity and public health services. Multiple fecal samples were collected from 88 individuals in PS and from 38 individuals in SM, who were asymptomatic at the time of sampling and had no recent history of diarrheal disease. To gain insights into potential transmission routes, 49 dog fecal samples (38 from PS and 11 from SM) and 28 river water samples were also collected. All samples were tested by microscopy and PCR was used to genotype Giardia duodenalis, Blastocystis sp., Dientamoeba fragilis and Cryptosporidium spp. By molecular methods, the most common human parasite was Blastocystis sp. (prevalence, 45% in PS and 71% in SM), followed by D. fragilis (13.6% in PS, and 18.4% in SM) and G. duodenalis (18.2% in PS and 7.9% in SM); Cryptosporidium spp. were not detected. Sequence analysis revealed large genetic variation among Blastocystis samples, with subtypes (STs) 1 and 3 being predominant, and with the notable absence of ST4. Among G. duodenalis samples, assemblages A and B were detected in humans, whereas assemblages A, C and D were found in dogs. Finally, all D. fragilis samples from humans were genotype 1. A single dog was found infected with Cryptosporidium canis. River water samples were negative for the investigated parasites. This study showed a high carriage of intestinal parasites in asymptomatic individuals from two poor Brazilian villages, and highlighted a large genetic variability of Blastocystis spp. and G. duodenalis.

No Paragonimus in high-risk groups in Côte d'Ivoire, but considerable prevalence of helminths and intestinal protozoon infections.

PubMed

Traoré, Sylvain G; Odermatt, Peter; Bonfoh, Bassirou; Utzinger, Jürg; Aka, N'da D; Adoubryn, Koffi D; Assoumou, Aka; Dreyfuss, Gilles; Koussémon, Marina

2011-06-03

Paragonimiasis is a neglected tropical disease caused by an infection with lung flukes that is transmitted through the consumption of undercooked crabs. The disease is often confused with tuberculosis. Paragonimiasis is thought to be endemic in south-western Côte d'Ivoire. Two cross-sectional surveys were carried out in the first half of 2009 in patients attending two tuberculosis centres of Abidjan. A third cross-sectional survey was conducted in May 2010 in children of two primary schools in Dabou, where crabs are frequently consumed. Patients with chronic cough provided three sputum samples plus one stool sample. Sputum samples were examined for tuberculosis with an auramine staining technique and for Paragonimus eggs using a concentration technique. Stool samples were subjected to the Ritchie technique. Schoolchildren provided a single stool sample, and samples were subjected to the Kato-Katz and an ether-concentration technique. A pre-tested questionnaire was administered to patients and schoolchildren to investigate food consumption habits. Additionally, between June 2009 and August 2010, shellfish were purchased from markets in Abidjan and Dabou and examined for metacercariae. No human case of paragonimiasis was diagnosed. However, trematode infections were seen in 32 of the 272 shellfish examined (11.8%). Questionnaire results revealed that crab and pig meat is well cooked before consumption. Among the 278 patients with complete data records, 62 had tuberculosis, with a higher prevalence in males than females (28.8% vs. 13.9%, χ2 = 8.79, p = 0.003). The prevalence of helminths and intestinal protozoa was 4.6% and 16.9%, respectively. In the school survey, among 166 children with complete data records, the prevalence of helminths and intestinal protozoa was 22.3% and 48.8%, respectively. Boys had significantly higher prevalences of helminths and intestinal protozoa than girls. Hookworm was the predominant helminth species and Entamoeba coli was the most common intestinal protozoon species (13.8%). Not a single case of Paragonimus was found in two high-risk groups of Côte d'Ivoire, most likely explained by food consumption habits. However, other helminth and intestinal protozoon infections were common.

No Paragonimus in high-risk groups in Côte d'Ivoire, but considerable prevalence of helminths and intestinal protozoon infections

PubMed Central

2011-01-01

Background Paragonimiasis is a neglected tropical disease caused by an infection with lung flukes that is transmitted through the consumption of undercooked crabs. The disease is often confused with tuberculosis. Paragonimiasis is thought to be endemic in south-western Côte d'Ivoire. Methods Two cross-sectional surveys were carried out in the first half of 2009 in patients attending two tuberculosis centres of Abidjan. A third cross-sectional survey was conducted in May 2010 in children of two primary schools in Dabou, where crabs are frequently consumed. Patients with chronic cough provided three sputum samples plus one stool sample. Sputum samples were examined for tuberculosis with an auramine staining technique and for Paragonimus eggs using a concentration technique. Stool samples were subjected to the Ritchie technique. Schoolchildren provided a single stool sample, and samples were subjected to the Kato-Katz and an ether-concentration technique. A pre-tested questionnaire was administered to patients and schoolchildren to investigate food consumption habits. Additionally, between June 2009 and August 2010, shellfish were purchased from markets in Abidjan and Dabou and examined for metacercariae. Results No human case of paragonimiasis was diagnosed. However, trematode infections were seen in 32 of the 272 shellfish examined (11.8%). Questionnaire results revealed that crab and pig meat is well cooked before consumption. Among the 278 patients with complete data records, 62 had tuberculosis, with a higher prevalence in males than females (28.8% vs. 13.9%, χ2 = 8.79, p = 0.003). The prevalence of helminths and intestinal protozoa was 4.6% and 16.9%, respectively. In the school survey, among 166 children with complete data records, the prevalence of helminths and intestinal protozoa was 22.3% and 48.8%, respectively. Boys had significantly higher prevalences of helminths and intestinal protozoa than girls. Hookworm was the predominant helminth species and Entamoeba coli was the most common intestinal protozoon species (13.8%). Conclusions Not a single case of Paragonimus was found in two high-risk groups of Côte d'Ivoire, most likely explained by food consumption habits. However, other helminth and intestinal protozoon infections were common. PMID:21639877

DEVELOPMENT OF HOMOLOGOUS VIRAL INTERNAL CONTROLS FOR USE IN RT-PCR ASSAYS OF WATERBORNE ENTERIC VIRUSES

EPA Science Inventory

Enteric viruses often contaminate water sources causing frequent outbreaks of gastroenteritis. Reverse transcription-polymerase chain reaction (RT-PCR) assays are commonly used for detection of human enteric viruses in environmental and drinking water samples. RT-PCR provides ...

Diagnosing clostridial enteric disease in poultry.

PubMed

Cooper, Kerry K; Songer, J Glenn; Uzal, Francisco A

2013-05-01

The world's poultry industry has grown into a multibillion-dollar business, the success of which hinges on healthy intestinal tracts, which result in effective feed conversion. Enteric disease in poultry can have devastating economic effects on producers, due to high mortality rates and poor feed efficiency. Clostridia are considered to be among the most important agents of enteric disease in poultry. Diagnosis of enteric diseases produced by clostridia is usually challenging, mainly because many clostridial species can be normal inhabitants of the gut, making it difficult to determine their role in virulence. The most common clostridial enteric disease in poultry is necrotic enteritis, caused by Clostridium perfringens, which typically occurs in broiler chickens but has also been diagnosed in various avian species including turkeys, waterfowl, and ostriches. Diagnosis is based on clinical and pathological findings. Negative culture and toxin detection results may be used to rule out this disease, but isolation of C. perfringens and/or detection of its alpha toxin are of little value to confirm the disease because both are often found in the intestine of healthy birds. Ulcerative enteritis, caused by Clostridium colinum, is the other major clostridial enteric disease of poultry. Diagnosis of ulcerative enteritis is by documentation of typical pathological findings, coupled with isolation of C. colinum from the intestine of affected birds. Other clostridial enteric diseases include infections produced by Clostridium difficile, Clostridium fallax, and Clostridium baratii.

Protozoan Bacterivory and Escherichia coli Survival in Drinking Water Distribution Systems

PubMed Central

Sibille, I.; Sime-Ngando, T.; Mathieu, L.; Block, J. C.

1998-01-01

The development of bacterial communities in drinking water distribution systems leads to a food chain which supports the growth of macroorganisms incompatible with water quality requirements and esthetics. Nevertheless, very few studies have examined the microbial communities in drinking water distribution systems and their trophic relationships. This study was done to quantify the microbial communities (especially bacteria and protozoa) and obtain direct and indirect proof of protozoan feeding on bacteria in two distribution networks, one of GAC water (i.e., water filtered on granular activated carbon) and the other of nanofiltered water. The nanofiltered water-supplied network contained no organisms larger than bacteria, either in the water phase (on average, 5 × 107 bacterial cells liter−1) or in the biofilm (on average, 7 × 106 bacterial cells cm−2). No protozoa were detected in the whole nanofiltered water-supplied network (water plus biofilm). In contrast, the GAC water-supplied network contained bacteria (on average, 3 × 108 cells liter−1 in water and 4 × 107 cells cm−2 in biofilm) and protozoa (on average, 105 cells liter−1 in water and 103 cells cm−2 in biofilm). The water contained mostly flagellates (93%), ciliates (1.8%), thecamoebae (1.6%), and naked amoebae (1.1%). The biofilm had only ciliates (52%) and thecamoebae (48%). Only the ciliates at the solid-liquid interface of the GAC water-supplied network had a measurable grazing activity in laboratory test (estimated at 2 bacteria per ciliate per h). Protozoan ingestion of bacteria was indirectly shown by adding Escherichia coli to the experimental distribution systems. Unexpectedly, E. coli was lost from the GAC water-supplied network more rapidly than from the nanofiltered water-supplied network, perhaps because of the grazing activity of protozoa in GAC water but not in nanofiltered water. Thus, the GAC water-supplied network contained a functional ecosystem with well-established and structured microbial communities, while the nanofiltered water-supplied system did not. The presence of protozoa in drinking water distribution systems must not be neglected because these populations may regulate the autochthonous and allochthonous bacterial populations. PMID:9435076

Protozoan bacterivory and Escherichia coli survival in drinking water distribution systems.

PubMed

Sibille, I; Sime-Ngando, T; Mathieu, L; Block, J C

1998-01-01

The development of bacterial communities in drinking water distribution systems leads to a food chain which supports the growth of macroorganisms incompatible with water quality requirements and esthetics. Nevertheless, very few studies have examined the microbial communities in drinking water distribution systems and their trophic relationships. This study was done to quantify the microbial communities (especially bacteria and protozoa) and obtain direct and indirect proof of protozoan feeding on bacteria in two distribution networks, one of GAC water (i.e., water filtered on granular activated carbon) and the other of nanofiltered water. The nanofiltered water-supplied network contained no organisms larger than bacteria, either in the water phase (on average, 5 x 10(7) bacterial cells liter-1) or in the biofilm (on average, 7 x 10(6) bacterial cells cm-2). No protozoa were detected in the whole nanofiltered water-supplied network (water plus biofilm). In contrast, the GAC water-supplied network contained bacteria (on average, 3 x 10(8) cells liter-1 in water and 4 x 10(7) cells cm-2 in biofilm) and protozoa (on average, 10(5) cells liter-1 in water and 10(3) cells cm-2 in biofilm). The water contained mostly flagellates (93%), ciliates (1.8%), thecamoebae (1.6%), and naked amoebae (1.1%). The biofilm had only ciliates (52%) and thecamoebae (48%). Only the ciliates at the solid-liquid interface of the GAC water-supplied network had a measurable grazing activity in laboratory test (estimated at 2 bacteria per ciliate per h). Protozoan ingestion of bacteria was indirectly shown by adding Escherichia coli to the experimental distribution systems. Unexpectedly, E. coli was lost from the GAC water-supplied network more rapidly than from the nanofiltered water-supplied network, perhaps because of the grazing activity of protozoa in GAC water but not in nanofiltered water. Thus, the GAC water-supplied network contained a functional ecosystem with well-established and structured microbial communities, while the nanofiltered water-supplied system did not. The presence of protozoa in drinking water distribution systems must not be neglected because these populations may regulate the autochthonous and allochthonous bacterial populations.

Prevalence and risk factors of helminths and intestinal protozoa infections among children from primary schools in western Tajikistan

PubMed Central

2011-01-01

Background Intestinal parasitic infections represent a public health problem in Tajikistan, but epidemiological evidence is scarce. The present study aimed at assessing the extent of helminths and intestinal protozoa infections among children of 10 schools in four districts of Tajikistan, and to make recommendations for control. Methods A cross-sectional survey was carried out in early 2009. All children attending grades 2 and 3 (age: 7-11 years) from 10 randomly selected schools were invited to provide a stool sample and interviewed about sanitary situation and hygiene behaviour. A questionnaire pertaining to demographic and socioeconomic characteristics was addressed to the heads of households. On the spot, stool samples were subjected to duplicate Kato-Katz thick smear examination for helminth diagnosis. Additionally, 1-2 g of stool was fixed in sodium acetate-acetic acid-formalin, transferred to a specialised laboratory in Europe and examined for helminths and intestinal protozoa. The composite results from both methods served as diagnostic 'gold' standard. Results Out of 623 registered children, 602 participated in our survey. The overall prevalence of infection with helminths and pathogenic intestinal protozoa was 32.0% and 47.1%, respectively. There was pronounced spatial heterogeneity. The most common helminth species was Hymenolepis nana (25.8%), whereas the prevalences of Ascaris lumbricoides, hookworm and Enterobius vermicularis were below 5%. The prevalence of pathogenic intestinal protozoa, namely Giardia intestinalis and Entamoeba histolytica/E. dispar was 26.4% and 25.9%, respectively. Almost half of the households draw drinking water from unimproved sources, such as irrigation canals, rivers and unprotected wells. Sanitary facilities were pit latrines, mostly private, and a few shared with neighbours. The use of public tap/standpipe as a source of drinking water emerged as a protective factor for G. intestinalis infection. Protected spring water reduced the risk of infection with E. histolytica/E. dispar and H. nana. Conclusions Our data obtained from the ecological 'lowland' areas in Tajikistan call for school-based deworming (recommended drugs: albendazole and metronidazole), combined with hygiene promotion and improved sanitation. Further investigations are needed to determine whether H. nana represents a public health problem. PMID:21981979

Prevalence and risk factors of helminths and intestinal protozoa infections among children from primary schools in western Tajikistan.

PubMed

Matthys, Barbara; Bobieva, Mohion; Karimova, Gulzira; Mengliboeva, Zulfira; Jean-Richard, Vreni; Hoimnazarova, Malika; Kurbonova, Matluba; Lohourignon, Laurent K; Utzinger, Jürg; Wyss, Kaspar

2011-10-07

Intestinal parasitic infections represent a public health problem in Tajikistan, but epidemiological evidence is scarce. The present study aimed at assessing the extent of helminths and intestinal protozoa infections among children of 10 schools in four districts of Tajikistan, and to make recommendations for control. A cross-sectional survey was carried out in early 2009. All children attending grades 2 and 3 (age: 7-11 years) from 10 randomly selected schools were invited to provide a stool sample and interviewed about sanitary situation and hygiene behaviour. A questionnaire pertaining to demographic and socioeconomic characteristics was addressed to the heads of households. On the spot, stool samples were subjected to duplicate Kato-Katz thick smear examination for helminth diagnosis. Additionally, 1-2 g of stool was fixed in sodium acetate-acetic acid-formalin, transferred to a specialised laboratory in Europe and examined for helminths and intestinal protozoa. The composite results from both methods served as diagnostic 'gold' standard. Out of 623 registered children, 602 participated in our survey. The overall prevalence of infection with helminths and pathogenic intestinal protozoa was 32.0% and 47.1%, respectively. There was pronounced spatial heterogeneity. The most common helminth species was Hymenolepis nana (25.8%), whereas the prevalences of Ascaris lumbricoides, hookworm and Enterobius vermicularis were below 5%. The prevalence of pathogenic intestinal protozoa, namely Giardia intestinalis and Entamoeba histolytica/E. dispar was 26.4% and 25.9%, respectively. Almost half of the households draw drinking water from unimproved sources, such as irrigation canals, rivers and unprotected wells. Sanitary facilities were pit latrines, mostly private, and a few shared with neighbours. The use of public tap/standpipe as a source of drinking water emerged as a protective factor for G. intestinalis infection. Protected spring water reduced the risk of infection with E. histolytica/E. dispar and H. nana. Our data obtained from the ecological 'lowland' areas in Tajikistan call for school-based deworming (recommended drugs: albendazole and metronidazole), combined with hygiene promotion and improved sanitation. Further investigations are needed to determine whether H. nana represents a public health problem.

Ruminal bacteria and protozoa composition, digestibility, and amino acid profile determined by multiple hydrolysis times.

PubMed

Fessenden, S W; Hackmann, T J; Ross, D A; Foskolos, A; Van Amburgh, M E

2017-09-01

Microbial samples from 4 independent experiments in lactating dairy cattle were obtained and analyzed for nutrient composition, AA digestibility, and AA profile after multiple hydrolysis times ranging from 2 to 168 h. Similar bacterial and protozoal isolation techniques were used for all isolations. Omasal bacteria and protozoa samples were analyzed for AA digestibility using a new in vitro technique. Multiple time point hydrolysis and least squares nonlinear regression were used to determine the AA content of omasal bacteria and protozoa, and equivalency comparisons were made against single time point hydrolysis. Formalin was used in 1 experiment, which negatively affected AA digestibility and likely limited the complete release of AA during acid hydrolysis. The mean AA digestibility was 87.8 and 81.6% for non-formalin-treated bacteria and protozoa, respectively. Preservation of microbe samples in formalin likely decreased recovery of several individual AA. Results from the multiple time point hydrolysis indicated that Ile, Val, and Met hydrolyzed at a slower rate compared with other essential AA. Singe time point hydrolysis was found to be nonequivalent to multiple time point hydrolysis when considering biologically important changes in estimated microbial AA profiles. Several AA, including Met, Ile, and Val, were underpredicted using AA determination after a single 24-h hydrolysis. Models for predicting postruminal supply of AA might need to consider potential bias present in postruminal AA flow literature when AA determinations are performed after single time point hydrolysis and when using formalin as a preservative for microbial samples. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Dasytricha dominance in Surti buffalo rumen revealed by 18S rRNA sequences and real-time PCR assay.

PubMed

Singh, K M; Tripathi, A K; Pandya, P R; Rank, D N; Kothari, R K; Joshi, C G

2011-09-01

The genetic diversity of protozoa in Surti buffalo rumen was studied by amplified ribosomal DNA restriction analysis, 18S rDNA sequence homology and phylogenetic and Real-time PCR analysis methods. Three animals were fed diet comprised green fodder Napier bajra 21 (Pennisetum purpureum), mature pasture grass (Dicanthium annulatum) and concentrate mixture (20% crude protein, 65% total digestible nutrients). A protozoa-specific primer (P-SSU-342f) and a eukarya-specific primer (Medlin B) were used to amplify a 1,360 bp fragment of DNA encoding protozoal small subunit (SSU) ribosomal RNA from rumen fluid. A total of 91 clones were examined and identified 14 different 18S RNA sequences based on PCR-RFLP pattern. These 14 phylotypes were distributed into four genera-based 18S rDNA database sequences and identified as Dasytricha (57 clones), Isotricha (14 clones), Ostracodinium (11 clones) and Polyplastron (9 clones). Phylogenetic analyses were also used to infer the makeup of protozoa communities in the rumen of Surti buffalo. Out of 14 sequences, 8 sequences (69 clones) clustered with the Dasytricha ruminantium-like clone and 4 sequences (13 clones) were also phylogenetically placed with the Isotricha prostoma-like clone. Moreover, 2 phylotypes (9 clones) were related to Polyplastron multivesiculatum-like clone. In addition, the number of 18S rDNA gene copies of Dasytricha ruminantium (0.05% to ciliate protozoa) was higher than Entodinium sp. (2.0 × 10(5) vs. 1.3 × 10(4)) in per ml ruminal fluid.

Canine Visceral Leishmaniasis, United States and Canada, 2000–2003

PubMed Central

Duprey, Zandra H.; Steurer, Francis J.; Rooney, Jane A.; Kirchhoff, Louis V.; Jackson, Joan E.; Rowton, Edgar D.

2006-01-01

Visceral leishmaniasis, caused by protozoa of the genus Leishmania donovani complex, is a vectorborne zoonotic infection that infects humans, dogs, and other mammals. In 2000, this infection was implicated as causing high rates of illness and death among foxhounds in a kennel in New York. A serosurvey of >12,000 foxhounds and other canids and 185 persons in 35 states and 4 Canadian provinces was performed to determine geographic extent, prevalence, host range, and modes of transmission within foxhounds, other dogs, and wild canids and to assess possible infections in humans. Foxhounds infected with Leishmania spp. were found in 18 states and 2 Canadian provinces. No evidence of infection was found in humans. The infection in North America appears to be widespread in foxhounds and limited to dog-to-dog mechanisms of transmission; however, if the organism becomes adapted for vector transmission by indigenous phlebotomines, the probability of human exposure will be greatly increased. PMID:16704782

Drug repurposing and human parasitic protozoan diseases

PubMed Central

Andrews, Katherine T.; Fisher, Gillian; Skinner-Adams, Tina S.

2014-01-01

Parasitic diseases have an enormous health, social and economic impact and are a particular problem in tropical regions of the world. Diseases caused by protozoa and helminths, such as malaria and schistosomiasis, are the cause of most parasite related morbidity and mortality, with an estimated 1.1 million combined deaths annually. The global burden of these diseases is exacerbated by the lack of licensed vaccines, making safe and effective drugs vital to their prevention and treatment. Unfortunately, where drugs are available, their usefulness is being increasingly threatened by parasite drug resistance. The need for new drugs drives antiparasitic drug discovery research globally and requires a range of innovative strategies to ensure a sustainable pipeline of lead compounds. In this review we discuss one of these approaches, drug repurposing or repositioning, with a focus on major human parasitic protozoan diseases such as malaria, trypanosomiasis, toxoplasmosis, cryptosporidiosis and leishmaniasis. PMID:25057459

[Visceral leishmaniasis in patient with HIV infection].

PubMed

Olea, Pilar; Pinilla, Jorge

2013-04-01

Leishmaniasis is a parasitic disease caused by the protozoa of the genus Leishmania transmitted by sandfly bites. It causes subclinical infection and diverse clinical manifestations with cutaneous, mucosal or visceral involvement. The last one, called visceral leishmaniasis, is usually fatal without treatment and in VIH patients with deep immunosuppression, has been recognized as an opportunistic infection with a high degree of difficulty in diagnosis and treatment. We present the case of a patient with HIV infection and visceral leishmaniasis. The clinical presentation was a prolonged febril syndrome with hepatosplenomegaly, lymphadenopathy and pancytopenia. The differential diagnosis was made with lymphoma and other opportunistic infections, as mycobacteriosis. The bone marrow aspirate reveled parasite amastigotes. The patient received treatment with amphotericin B deoxycholate for 14 days and 2 months after he relapsed. Then he was treated with the same drug for 21 days and after that he has been in prophylaxis for 29 months with good outcome, without any other relapse.

The impact of albendazole treatment on the incidence of viral- and bacterial-induced diarrhea in school children in southern Vietnam: study protocol for a randomized controlled trial.

PubMed

Leung, Jacqueline M; Hong, Chau Tran Thi; Trung, Nghia Ho Dang; Thi, Hoa Nhu; Minh, Chau Nguyen Ngoc; Thi, Thuy Vu; Hong, Dinh Thanh; Man, Dinh Nguyen Huy; Knowles, Sarah C L; Wolbers, Marcel; Hoang, Nhat Le Thanh; Thwaites, Guy; Graham, Andrea L; Baker, Stephen

2016-06-06

Anthelmintics are one of the more commonly available classes of drugs to treat infections by parasitic helminths (especially nematodes) in the human intestinal tract. As a result of their cost-effectiveness, mass school-based deworming programs are becoming routine practice in developing countries. However, experimental and clinical evidence suggests that anthelmintic treatments may increase susceptibility to other gastrointestinal infections caused by bacteria, viruses, or protozoa. Hypothesizing that anthelmintics may increase diarrheal infections in treated children, we aim to evaluate the impact of anthelmintics on the incidence of diarrheal disease caused by viral and bacterial pathogens in school children in southern Vietnam. This is a randomized, double-blinded, placebo-controlled trial to investigate the effects of albendazole treatment versus placebo on the incidence of viral- and bacterial-induced diarrhea in 350 helminth-infected and 350 helminth-uninfected Vietnamese school children aged 6-15 years. Four hundred milligrams of albendazole, or placebo treatment will be administered once every 3 months for 12 months. At the end of 12 months, all participants will receive albendazole treatment. The primary endpoint of this study is the incidence of diarrheal disease assessed by 12 months of weekly active and passive case surveillance. Secondary endpoints include the prevalence and intensities of helminth, viral, and bacterial infections, alterations in host immunity and the gut microbiota with helminth and pathogen clearance, changes in mean z scores of body weight indices over time, and the number and severity of adverse events. In order to reduce helminth burdens, anthelmintics are being routinely administered to children in developing countries. However, the effects of anthelmintic treatment on susceptibility to other diseases, including diarrheal pathogens, remain unknown. It is important to monitor for unintended consequences of drug treatments in co-infected populations. In this trial, we will examine how anthelmintic treatment impacts host susceptibility to diarrheal infections, with the aim of informing deworming programs of any indirect effects of mass anthelmintic administrations on co-infecting enteric pathogens. ClinicalTrials.gov: NCT02597556 . Registered on 3 November 2015.

First report of predation of Giardia sp. cysts by ciliated protozoa and confirmation of predation of Cryptosporidium spp. oocysts by ciliate species.

PubMed

Siqueira-Castro, Isabel Cristina Vidal; Greinert-Goulart, Juliane Araújo; Bonatti, Tais Rondello; Yamashiro, Sandra; Franco, Regina Maura Bueno

2016-06-01

Ciliated protozoa are important components of the microbial food web in various habitats, especially aquatic environments. These organisms are useful bioindicators for both environmental quality assessment and the wastewater purification process. The pathogenic parasitic protozoan species Giardia and Cryptosporidium represent a significant concern for human health, being responsible for numerous disease outbreaks worldwide. The predation of cysts and oocysts in 15 ciliate species from water and sewage samples collected in Campinas, São Paulo, Brazil were verified under laboratory conditions. The ciliated protozoan species were selected based on their mode of nutrition, and only bacterivorous and suspension-feeders were considered for the experiments. The species Blepharisma sinuosum, Euplotes aediculatus, Sterkiella cavicola, Oxytricha granulifera, Vorticella infusionum, Spirostomum minus, and Stentor coeruleus ingested cysts and oocysts, the resistance forms of Giardia spp. and Cryptosporidium spp., respectively. This is the first time that the ingestion of Giardia cysts by ciliated protozoa has been reported. These findings may contribute to a better understanding of the biological removal of these pathogens from aquatic environments.

Food handlers as a link in the chain of transmission of Giardia duodenalis and other protozoa in public schools in southern Brazil.

PubMed

Colli, Cristiane Maria; Bezagio, Renata Coltro; Nishi, Letícia; Ferreira, Érika Cristina; Falavigna-Guilherme, Ana Lúcia; Gomes, Mônica Lúcia

2015-09-01

Food handlers (FHs) may facilitate transmission and dissemination of pathogens. The importance of FHs as a link in the epidemiological chain of transmission of Giardia duodenalis and other intestinal protozoa was assessed. Fecal and subungual material from 27 FHs were analyzed using parasitological methods. G. duodenalis was identified by direct immunofluorescence and genotyped by PCR-RFLP for the bg and gdh genes, and gdh was sequenced. At least one protozoan was detected in 30% (8/27) of the FHs and G. duodenalis (19%; 5/27) was the most common species. The AII and BIV genotypes were found in 20% (1/5) and 60% (3/5) of FHs infected with G. duodenalis, respectively. FHs can be involved in the chain of transmission of G. duodenalis and other protozoa. KJ741310 - KJ741313. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Technical note: A method for isolating glycogen granules from ruminal protozoa for further characterization.

PubMed

Hall, Mary Beth

2016-03-01

Evaluation of physical, chemical, and enzymatic hydrolysis characteristics of protozoal glycogen is best performed on a pure substrate to avoid interference from other cell components. A method for isolating protozoal glycogen granules without use of detergents or other potentially contaminating chemicals was developed. Rumen inoculum was incubated anerobically in vitro with glucose. Glycogen-laden protozoa produced in the fermentation, primarily isotrichids, were allowed to sediment in a separatory funnel and were dispensed. The protozoa were processed through repeated centrifugations and sonication to isolate glycogen granules largely free of feed and cellular debris. The final water-insoluble lyophilized product analyzed as 98.3% α-glucan with very rare starch granules and 1.9% protein. Observed losses of glycogen granules during the clean-up process indicate that this procedure should not be used for quantitative assessment of protozoal glycogen from fermentations. Further optimization of this procedure to enhance the amount of glycogen obtained per fermentation may be possible. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Polyketide synthase (PKS) reduces fusion of Legionella pneumophila-containing vacuoles with lysosomes and contributes to bacterial competitiveness during infection.

PubMed

Shevchuk, Olga; Pägelow, Dennis; Rasch, Janine; Döhrmann, Simon; Günther, Gabriele; Hoppe, Julia; Ünal, Can Murat; Bronietzki, Marc; Gutierrez, Maximiliano Gabriel; Steinert, Michael

2014-11-01

L. pneumophila-containing vacuoles (LCVs) exclude endocytic and lysosomal markers in human macrophages and protozoa. We screened a L. pneumophila mini-Tn10 transposon library for mutants, which fail to inhibit the fusion of LCVs with lysosomes by loading of the lysosomal compartment with colloidal iron dextran, mechanical lysis of infected host cells, and magnetic isolation of LCVs that have fused with lysosomes. In silico analysis of the mutated genes, D. discoideum plaque assays and infection assays in protozoa and U937 macrophage-like cells identified well established as well as novel putative L. pneumophila virulence factors. Promising candidates were further analyzed for their co-localization with lysosomes in host cells using fluorescence microscopy. This approach corroborated that the O-methyltransferase, PilY1, TPR-containing protein and polyketide synthase (PKS) of L. pneumophila interfere with lysosomal degradation. Competitive infections in protozoa and macrophages revealed that the identified PKS contributes to the biological fitness of pneumophila strains and may explain their prevalence in the epidemiology of Legionnaires' disease. Copyright © 2014 Elsevier GmbH. All rights reserved.

Calcium Montmorillonite-based dietary supplement attenuates Necrotic Enteritis induced by Eimeria maxima and Clostridium perfringens in broilers

USDA-ARS?s Scientific Manuscript database

We provide the first description of Dietary Supplement of sorbent minerals attenuates Necrotic Enteritis Induced by Eimeria maxima and Clostridium perfringens in Broilers. Necrotic enteritis (NE) is a poultry disease caused by Clostridium perfringens and characterized by severe intestinal necrosis....

Highlights of the São Paulo ISEV workshop on extracellular vesicles in cross-kingdom communication

PubMed Central

Soares, Rodrigo P.; Xander, Patrícia; Costa, Adriana Oliveira; Marcilla, Antonio; Menezes-Neto, Armando; Del Portillo, Hernando; Witwer, Kenneth; Wauben, Marca; Nolte-`T Hoen, Esther; Olivier, Martin; Criado, Miriã Ferreira; da Silva, Luis Lamberti P.; Abdel Baqui, Munira Muhammad; Schenkman, Sergio; Colli, Walter; Alves, Maria Julia Manso; Ferreira, Karen Spadari; Puccia, Rosana; Nejsum, Peter; Riesbeck, Kristian; Stensballe, Allan; Hansen, Eline Palm; Jaular, Lorena Martin; Øvstebø, Reidun; de la Canal, Laura; Bergese, Paolo; Pereira-Chioccola, Vera; Pfaffl, Michael W.; Fritz, Joëlle; Gho, Yong Song; Torrecilhas, Ana Claudia

2017-01-01

ABSTRACT In the past years, extracellular vesicles (EVs) have become an important field of research since EVs have been found to play a central role in biological processes. In pathogens, EVs are involved in several events during the host–pathogen interaction, including invasion, immunomodulation, and pathology as well as parasite–parasite communication. In this report, we summarised the role of EVs in infections caused by viruses, bacteria, fungi, protozoa, and helminths based on the talks and discussions carried out during the International Society for Extracellular Vesicles (ISEV) workshop held in São Paulo (November, 2016), Brazil, entitled Cross-organism Communication by Extracellular Vesicles: Hosts, Microbes and Parasites.

Clinical and pathological observations on natural infections of cryptosporidiosis and flagellate protozoa in leopard geckos (Eublepharis macularius).

PubMed

Taylor, M A; Geach, M R; Cooley, W A

1999-12-11

A group of adult leopard geckos (Eublepharis macularius) which had been losing weight for several months were found to be infected with Cryptosporidium species. Histological and electron microscopical investigations on the intestines of five of the lizards revealed the presence of large numbers of the developmental stages of Cryptosporidium species attached to the mucosal surface of the lower intestine, and large numbers of flagellate protozoa, suspected to be predominantly Trichomonas species, in the gut lumen. The clinical signs were attributed to the presence of one or both types of parasites.

Inosine 5'-Monophosphate Dehydrogenase (IMPDH) as a Potential Target for the Development of a New Generation of Antiprotozoan Agents.

PubMed

Fotie, Jean

2018-01-01

Inosine-5'-monophosphate dehydrogenase (IMPDH) is a metabolic enzyme that catalyzes the critical step in guanine nucleotide biosynthesis, and thus is at the center of cell growth and proliferation. However, although this enzyme has been exploited as potential target for the development of immunosuppressive, anticancer, and antiviral agents, the functional importance of IMPDH as a promising antiprotozoan drug target is still in its infancy mainly because of the availability of alternative nucleotides metabolic pathways in many of these parasites. This situation suggests that the inhibition of IMPDH might have little to no effect on the survival of protozoan parasites. As a result, no IMPDH inhibitor is currently commercially available or has advanced to clinical trials as a potential antiprotozoan drug. Nevertheless, recent advances toward the development of selective inhibitors of the IMPDH enzyme from Crystosporidium parvum as potential drug candidates against cryptosporidiosis should revive further investigations of this drug target in other protozoa parasites. The current review examines the chemical structures and biological activities of reported protozoan's IMPDH inhibitors. SciFinder was used to broadly pinpoint reports published on the topic in the chemical literature, with no specific time frame. Opportunities and challenges towards the development of inhibitors of IMPDH enzymes from protozoa parasites as potential chemotherapies toward the respective diseases they cause are also discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Bioaugmentation Mitigates the Impact of Estrogen on Coliform-Grazing Protozoa in Slow Sand Filters.

PubMed

Haig, Sarah-Jane; Gauchotte-Lindsay, Caroline; Collins, Gavin; Quince, Christopher

2016-03-15

Exposure to endocrine-disrupting chemicals (EDCs), such as estrogens, is a growing issue for human and animal health as they have been shown to cause reproductive and developmental abnormalities in wildlife and plants and have been linked to male infertility disorders in humans. Intensive farming and weather events, such as storms, flash flooding, and landslides, contribute estrogen to waterways used to supply drinking water. This paper explores the impact of estrogen exposure on the performance of slow sand filters (SSFs) used for water treatment. The feasibility and efficacy of SSF bioaugmentation with estrogen-degrading bacteria was also investigated, to determine whether removal of natural estrogens (estrone, estradiol, and estriol) and overall SSF performance for drinking water treatment could be improved. Strains for SSF augmentation were isolated from full-scale, municipal SSFs so as to optimize survival in the laboratory-scale SSFs used. Concentrations of the natural estrogens, determined by gas chromatography coupled with mass spectrometry (GC-MS), revealed augmented SSFs reduced the overall estrogenic potency of the supplied water by 25% on average and removed significantly more estrone and estradiol than nonaugmented filters. A negative correlation was found between coliform removal and estrogen concentration in nonaugmented filters. This was due to the toxic inhibition of protozoa, indicating that high estrogen concentrations can have functional implications for SSFs (such as impairing coliform removal). Consequently, we suggest that high estrogen concentrations could impact significantly on water quality production and, in particular, on pathogen removal in biological water filters.

Acute Pericarditis

MedlinePlus

... and white blood cells to enter the pericardial space. Infection and other conditions that inflame the pericardium ... can cause excess fluid to enter the pericardial space (pericardial effusion). Sometimes, when pericarditis is due to ...

Necrotizing enteritis as a cause of mortality in Laysan albatross, Diomedea immutabilis, chicks on Midway Atoll, Hawaii

USGS Publications Warehouse

Work, Thierry M.; Smith, M.R.; Duncan, R.

1998-01-01

A necropsy survey of Laysan albatross, Diomedea immutabilis, chicks on Midway Atoll in June 1993, 1994, and 1995 revealed 54% (21/39), 67% (49/71), and 93% (15/16), respectively, to have enteritis as the most severe pathologic finding. The lesion was limited to the ileum, ceca, and large intestine. We were unable to attribute a single infectious etiology to this lesion. Many birds with enteritis also exhibited renal lesions similar to those encountered in chickens experimentally deprived of water. We propose that enteritis is a significant cause of mortality in Laysan albatross chicks on Midway and that it may be a sequela to dehydration. It is likely that the pathology of dehydration in Laysan albatross differs from that in chickens largely because of diet.

Anomalous event diagnosis for environmental satellite systems

NASA Technical Reports Server (NTRS)

Ramsay, Bruce H.

1993-01-01

The National Oceanic and Atmospheric Administration's (NOAA) National Environmental Satellite, Data, and Information Service (NESDIS) is responsible for the operation of the NOAA geostationary and polar orbiting satellites. NESDIS provides a wide array of operational meteorological and oceanographic products and services and operates various computer and communication systems on a 24-hour, seven days per week schedule. The Anomaly Reporting System contains a database of anomalous events regarding the operations of the Geostationary Operational Environmental Satellite (GOES), communication, or computer systems that have degraded or caused the loss of GOES imagery. Data is currently entered manually via an automated query user interface. There are 21 possible symptoms (e.g., No Data), and 73 possible causes (e.g., Sectorizer - World Weather Building) of an anomalous event. The determination of an event's cause(s) is made by the on-duty computer operator, who enters the event in a paper based daily log, and by the analyst entering the data into the reporting system. The determination of the event's cause(s) impacts both the operational status of these systems, and the performance evaluation of the on-site computer and communication operations contractor.

The Interplay Between Predation, Competition, and Nutrient Levels Influences the Survival of Escherichia coli in Aquatic Environments.

PubMed

Wanjugi, P; Fox, G A; Harwood, V J

2016-10-01

Nutrient levels, competition from autochthonous microorganisms, and protozoan predation may all influence survival of fecal microorganisms as they transition from the gastrointestinal tract to aquatic habitats. Although Escherichia coli is an important indicator of waterborne pathogens, the effects of environmental stressors on its survival in aquatic environments remain poorly understood. We manipulated organic nutrient, predation, and competition levels in outdoor microcosms containing natural river water, sediments, and microbial populations to determine their relative contribution to E. coli survival. The activities of predator (protozoa) and competitor (indigenous bacteria) populations were inhibited by adding cycloheximide or kanamycin. We developed a statistical model of E. coli density over time that fits with the data under all experimental conditions. Predation and competition had significant negative effects on E. coli survival, while higher nutrient levels increased survival. Among the main effects, predation accounted for the greatest variation (40 %) compared with nutrients (25 %) or competition (15 %). The highest nutrient level mitigated the effect of predation on E. coli survival. Thus, elevated organic nutrients may disproportionately enhance the survival of E. coli, and potentially that of other enteric bacteria, in aquatic habitats.

Environmental and individual determinants of parasite richness across seasons in a free-ranging population of Mandrills (Mandrillus sphinx).

PubMed

Poirotte, Clémence; Basset, Didier; Willaume, Eric; Makaba, Fred; Kappeler, Peter M; Charpentier, Marie J E

2016-03-01

Parasites are ubiquitous and evolve fast. Therefore, they represent major selective forces acting on their hosts by influencing many aspects of their biology. Humans are no exception, as they share many parasites with animals and some of the most important outbreaks come from primates. While it appears important to understand the factors involved in parasite dynamics, we still lack a clear understanding of the determinants underlying parasitism. In this 2-year study, we identified several factors that influence parasite patterns in a wild population of free-ranging mandrills (Mandrillus sphinx). We explored the potential impact of seasonal factors-rainfall and temperature-and host characteristics, including sex, age, rank, and reproductive status, on parasite richness. We analyzed 12 parasite taxa found in 870 fecal samples collected from 63 individuals. Because nematodes and protozoa have different life-cycles, we analyzed these two types of parasites separately. Contrary to other studies where humid conditions seem favorable to parasite development, we report here that rainfall and high temperatures were associated with lower nematode richness and were not associated with lower protozoa richness. In contrast, female reproductive status seemed to reflect the seasonal patterns found for protozoa richness, as early gestating females harbored more protozoa than other females. Sex and dominance rank had no impact on overall parasite richness. However, age was associated with a specific decrease in nematode richness. Our study emphasizes the need to consider the ecological context, such as climatic conditions and habitat type, as well as the biology of both parasite and host when analyzing determinants of parasite richness. © 2015 Wiley Periodicals, Inc.

Microscopic diagnosis of sodium acetate-acetic acid-formalin-fixed stool samples for helminths and intestinal protozoa: a comparison among European reference laboratories.

PubMed

Utzinger, J; Botero-Kleiven, S; Castelli, F; Chiodini, P L; Edwards, H; Köhler, N; Gulletta, M; Lebbad, M; Manser, M; Matthys, B; N'Goran, E K; Tannich, E; Vounatsou, P; Marti, H

2010-03-01

The present study aimed to compare the diagnostic performance of different European reference laboratories in diagnosing helminths and intestinal protozoa, using an ether-concentration method applied to sodium acetate-acetic acid-formalin (SAF)-preserved faecal samples. In total, 102 stool specimens were analysed during a cross-sectional parasitological survey in urban farming communities in Côte d'Ivoire. Five SAF-preserved faecal samples were prepared from each specimen and forwarded to the participating reference laboratories, processed and examined under a microscope adhering to a standard operating procedure (SOP). Schistosoma mansoni (cumulative prevalence: 51.0%) and hookworm (cumulative prevalence: 39.2%) were the predominant helminths. There was excellent agreement (kappa > 0.8; p < 0.001) among the reference laboratories for the diagnosis of S. mansoni, hookworm, Trichuris trichiura and Ascaris lumbricoides. Moderate agreement (kappa = 0.54) was found for Hymenolepis nana, and lesser agreement was observed for other, less prevalent helminths. The predominant intestinal protozoa were Entamoeba coli (median prevalence: 67.6%), Blastocystis hominis (median prevalence: 55.9%) and Entamoeba histolytica/Entamoeba dispar (median prevalence: 47.1%). Substantial agreement among reference laboratories was found for E. coli (kappa = 0.69), but only fair or moderate agreement was found for other Entamoeba species, Giardia intestinalis and Chilomastix mesnili. There was only poor agreement for B. hominis, Isospora belli and Trichomonas intestinalis. In conclusion, although common helminths were reliably diagnosed by European reference laboratories, there was only moderate agreement between centres for pathogenic intestinal protozoa. Continued external quality assessment and the establishment of a formal network of reference laboratories is necessary to further enhance both accuracy and uniformity in parasite diagnosis.

Helminth and Intestinal Protozoa Infections, Multiparasitism and Risk Factors in Champasack Province, Lao People's Democratic Republic

PubMed Central

Sayasone, Somphou; Mak, Tippi K.; Vanmany, Monely; Rasphone, Oroth; Vounatsou, Penelope; Utzinger, Jürg; Akkhavong, Kongsap; Odermatt, Peter

2011-01-01

Background Detailed investigations of multiparasitism are scarce in the Mekong River basin. We assessed helminth (trematode, nematode, and cestode), and intestinal protozoa infections, and multiparasitism in random population samples from three different eco-epidemiological settings in Champasack province, southern Lao People's Democratic Republic (Lao PDR), and determined underlying risk factors. Methodology Two stool samples were collected from 669 individuals aged ≥6 months over consecutive days and examined for helminth infections using the Kato-Katz method. Additionally, one stool sample per person was subjected to a formalin-ethyl acetate concentration technique for diagnosis of helminth and intestinal protozoa infections. Questionnaires were administered to obtain individual and household-level data pertaining to behavior, demography and socioeconomic status. Risk factors for hepato-biliary and intestinal parasitic infections and multiparasitism were determined using multiple logistic regressions analyses. Principal Findings Multiple species intestinal parasite infections were common: 86.6% of the study participants harbored at least two and up to seven different parasites concurrently. Regarding nematode infections, hookworm was the most prevalent species (76.8%), followed by Ascaris lumbricoides (31.7%) and Trichuris trichiura (25.0%). Regarding trematodes, Opisthorchis viverrini and Schistosoma mekongi infections were found in 64.3% and 24.2% of the participants, respectively. Infections with intestinal protozoa were rare. Conclusions/Significance There is a pressing need to intensify and sustain helminth control interventions in the southern part of Lao PDR. Given the high prevalence with nematode and trematode infections and the extent of multiparasitism, preventive chemotherapy is warranted. This intervention should be coupled with health education and improved access to clean water and adequate sanitation to consolidate morbidity control and enhance sustainability. PMID:21532735

The CRISPR/Cas9 system sheds new lights on the biology of protozoan parasites.

PubMed

Grzybek, Maciej; Golonko, Aleksandra; Górska, Aleksandra; Szczepaniak, Klaudiusz; Strachecka, Aneta; Lass, Anna; Lisowski, Paweł

2018-06-01

The CRISPR/Cas9 system, a natural defence system of bacterial organisms, has recently been used to modify genomes of the most important protozoa parasites. Successful genome manipulations with the CRISPR/Cas9 system are changing the present view of genetics in parasitology. The application of this system offers a major chance to overcome the current restriction in culturing, maintaining and analysing protozoan parasites, and allows dynamic analysis of parasite genes functions, leading to a better understanding of pathogenesis. CRISPR/Cas9 system will have a significant influence on the process of developing novel drugs and treatment strategies against protozoa parasites.

Detection of Zoonotic Protozoa Toxoplasma gondii and Sarcocystis suihominis in Wild Boars from Spain.

PubMed

Calero-Bernal, R; Pérez-Martín, J E; Reina, D; Serrano, F J; Frontera, E; Fuentes, I; Dubey, J P

2016-08-01

Food safety regulations require the control of the presence of protozoa in meats destined for human consumption. Wild boar (Sus scrofa) meat may constitute a source of zoonoses. A 23.8% (688/2881) seroprevalence of anti-Toxoplasma gondii antibodies and 72.2% (662/910) Sarcocystis sarcocysts prevalence were detected among wild boars hunted in Southwestern areas of Spain. Identity of Sarcocystis spp. was performed by RFLP-PCR and sequencing, detecting S. miescheriana (7/8) and the zoonotic S. suihominis (1/8). Risk assessment studies of these coccidian in meats destined to human consumption are needed. © 2015 Blackwell Verlag GmbH.

Parasites in pet reptiles

PubMed Central

2011-01-01

Exotic reptiles originating from the wild can be carriers of many different pathogens and some of them can infect humans. Reptiles imported into Slovenia from 2000 to 2005, specimens of native species taken from the wild and captive bred species were investigated. A total of 949 reptiles (55 snakes, 331 lizards and 563 turtles), belonging to 68 different species, were examined for the presence of endoparasites and ectoparasites. Twelve different groups (Nematoda (5), Trematoda (1), Acanthocephala (1), Pentastomida (1) and Protozoa (4)) of endoparasites were determined in 26 (47.3%) of 55 examined snakes. In snakes two different species of ectoparasites were also found. Among the tested lizards eighteen different groups (Nematoda (8), Cestoda (1), Trematoda (1), Acanthocephala (1), Pentastomida (1) and Protozoa (6)) of endoparasites in 252 (76.1%) of 331 examined animals were found. One Trombiculid ectoparasite was determined. In 563 of examined turtles eight different groups (Nematoda (4), Cestoda (1), Trematoda (1) and Protozoa (2)) of endoparasites were determined in 498 (88.5%) animals. In examined turtles three different species of ectoparasites were seen. The established prevalence of various parasites in reptiles used as pet animals indicates the need for examination on specific pathogens prior to introduction to owners. PMID:21624124

Occurrence of Cryptosporidium and Giardia and the Relationship between Protozoa and Water Quality Indicators in Swimming Pools.

PubMed

Xiao, Shumin; Yin, Pengna; Zhang, Yan; Hu, Sike

2017-04-01

A total of 60 samples were collected from 35 swimming pools in Beijing, China, and the presence of Cryptosporidium and Giardia were investigated. The results showed that 16.7% and 15.0% of samples were positive for Cryptosporidium oocyst and Giardia cysts, respectively, with a mean concentration of 0.30 oocysts/10 L and 0.27 cysts/10 L. The oocysts and cysts were found to have higher rates of occurrence in August than in May. Genotyping confirmed the presence of Cryptosporidium hominis, C. parvum , and Giardia assemblages A and B, all of which were associated with human infections. The predominant species/assemblages were C. hominis and Giardia assemblage A. Analyses of the relationships between parasite oocysts/cysts, indicator bacteria, and physical-chemical parameters revealed that there was no correlation between 2 parasites and fecal bacterial indicators, whilst there was a significant correlation between protozoa and urea concentration, which indicates that urea concentration rather than fecal bacterial indicators might be an appropriate index for chlorine-resistant protozoa in swimming pools. This study provides useful information to improve the safety of swimming pool water and deduce the risk of protozoan infections.

An adhesin from hydrogen-utilizing rumen methanogen Methanobrevibacter ruminantium M1 binds a broad range of hydrogen-producing microorganisms.

PubMed

Ng, Filomena; Kittelmann, Sandra; Patchett, Mark L; Attwood, Graeme T; Janssen, Peter H; Rakonjac, Jasna; Gagic, Dragana

2016-09-01

Symbiotic associations are ubiquitous in the microbial world and have a major role in shaping the evolution of both partners. One of the most interesting mutualistic relationships exists between protozoa and methanogenic archaea in the fermentative forestomach (rumen) of ruminant animals. Methanogens reside within and on the surface of protozoa as symbionts, and interspecies hydrogen transfer is speculated to be the main driver for physical associations observed between the two groups. In silico analyses of several rumen methanogen genomes have previously shown that up to 5% of genes encode adhesin-like proteins, which may be central to rumen interspecies attachment. We hypothesized that adhesin-like proteins on methanogen cell surfaces facilitate attachment to protozoal hosts. Using phage display technology, we have identified a protein (Mru_1499) from Methanobrevibacter ruminantium M1 as an adhesin that binds to a broad range of rumen protozoa (including the genera Epidinium and Entodinium). This unique adhesin also binds the cell surface of the bacterium Butyrivibrio proteoclasticus, suggesting a broad adhesion spectrum for this protein. © 2015 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

Infection Status of Hospitalized Diarrheal Patients with Gastrointestinal Protozoa, Bacteria, and Viruses in the Republic of Korea

PubMed Central

Cho, Shin-Hyeong; Lee, Jin-Hee; Lim, Yi-Young; Jeon, Ji-Hye; Yu, Jae-Ran; Kim, Tong-Soo; Lee, Won-Ja; Cho, Seung-Hak; Lee, Deog-Yong; Park, Mi-Seon; Jeong, Hye-Sook; Chen, Doo-Sung; Ji, Yeong-Mi; Kwon, Mi-Hwa

2010-01-01

To understand protozoan, viral, and bacterial infections in diarrheal patients, we analyzed positivity and mixed-infection status with 3 protozoans, 4 viruses, and 10 bacteria in hospitalized diarrheal patients during 2004-2006 in the Republic of Korea. A total of 76,652 stool samples were collected from 96 hospitals across the nation. The positivity for protozoa, viruses, and bacteria was 129, 1,759, and 1,797 per 10,000 persons, respectively. Especially, Cryptosporidium parvum was highly mixed-infected with rotavirus among pediatric diarrheal patients (29.5 per 100 C. parvum positive cases), and Entamoeba histolytica was mixed-infected with Clostridium perfringens (10.3 per 100 E. histolytica positive cases) in protozoan-diarrheal patients. Those infected with rotavirus and C. perfringens constituted relatively high proportions among mixed infection cases from January to April. The positivity for rotavirus among viral infection for those aged ≤ 5 years was significantly higher, while C. perfringens among bacterial infection was higher for ≥ 50 years. The information for association of viral and bacterial infections with enteropathogenic protozoa in diarrheal patients may contribute to improvement of care for diarrhea as well as development of control strategies for diarrheal diseases in Korea. PMID:20585526

Detection of Pathogenic Protozoa in the Diagnostic Laboratory: Result Reproducibility, Specimen Pooling, and Competency Assessment▿

PubMed Central

Libman, M. D.; Gyorkos, T. W.; Kokoskin, E.; MacLean, J. D.

2008-01-01

Stool microscopy as performed in clinical parasitology laboratories is a complex procedure with subjective interpretation. Quality assurance (QA) programs often emphasize proficiency testing as an assessment tool. We describe a result reproducibility assessment tool, which can form part of a broader QA program, and which is based on the blinded resubmission of selected clinical samples, using concordance between the reports of the initial and resubmitted specimen as an indicator. Specimens preserved in sodium acetate-acetic acid-formalin can be stored for several months for use in such a program. The presence of multiple protozoa in one specimen does not affect concordance. Some dilution of specimens occurs in this process, and this may explain poor concordance when specimens with low protozoal concentrations are resubmitted. Evaluation of this tool in a large parasitology laboratory revealed concordance rates for pathogenic protozoa (Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Dientamoeba fragilis) of about 80%, which may be considered for use as a benchmark value. We also used this tool to demonstrate that when pairs of specimens from one patient are pooled to create a single specimen, concordance between the results of the individual and pooled specimens is high. PMID:18448690

Methane production, ruminal fermentation characteristics, nutrient digestibility, nitrogen excretion, and milk production of dairy cows fed conventional or brown midrib corn silage.

PubMed

Hassanat, F; Gervais, R; Benchaar, C

2017-04-01

The objective of this study was to examine the effect of replacing conventional corn silage (CCS) with brown midrib corn silage (BMCS) in dairy cow diets on enteric CH 4 emission, nutrient intake, digestibility, ruminal fermentation characteristics, milk production, and N excretion. Sixteen rumen-cannulated lactating cows used in a crossover design (35-d periods) were fed (ad libitum) a total mixed ration (forage:concentrate ratio = 65:35, dry matter basis) based (59% dry matter) on either CCS or BMCS. Dry matter intake and milk yield increased when cows were fed BMCS instead of CCS. Of the milk components, only milk fat content slightly decreased when cows were fed the BMCS-based diet compared with when fed the CCS-based diet (3.81 vs. 3.92%). Compared with CCS, feeding BMCS to cows increased yields of milk protein and milk fat. Ruminal pH, protozoa numbers, total VFA concentration, and molar proportions of acetate and propionate were similar between cows fed BMCS and those fed CCS. Daily enteric CH 4 emission (g/d) was unaffected by dietary treatments, but CH 4 production expressed as a proportion of gross energy intake or on milk yield basis was lower for cows fed the BMCS-based diet than for cows fed the CCS-based diet. A decline in manure N excretion and a shift in N excretion from urine to feces were observed when BMCS replaced CCS in the diet, suggesting reduced potential of manure N volatilization. Results from this study show that improving fiber quality of corn silage in dairy cow diets through using brown midrib trait cultivar can reduce enteric CH 4 emissions as well as potential emissions of NH 3 and N 2 O from manure. However, CH 4 emissions during manure storage may increase due to excretion of degradable OM when BMCS diet is fed, which merits further investigation. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Nitrate but not tea saponin feed additives decreased enteric methane emissions in nonlactating cows.

PubMed

Guyader, J; Eugène, M; Doreau, M; Morgavi, D P; Gérard, C; Loncke, C; Martin, C

2015-11-01

Tea saponin is considered a promising natural compound for reducing enteric methane emissions in ruminants. A trial was conducted to study the effect of this plant extract fed alone or in combination with nitrate on methane emissions, total tract digestive processes, and ruminal characteristics in cattle. The experiment was conducted as a 2 × 2 factorial design with 4 ruminally cannulated nonlactating dairy cows. Feed offer was restricted to 90% of voluntary intake and diets consisted of (DM basis): 1) control (CON; 50% hay and 50% pelleted concentrates), 2) CON with 0.5% tea saponin (TEA), 3) CON with 2.3% nitrate (NIT), and 4) CON with 0.5% tea saponin and 2.3% nitrate (TEA+NIT). Tea saponin and nitrate were included in pelleted concentrates. Diets contained similar amounts of CP (12.2%), starch (26.0%), and NDF (40.1%). Experimental periods lasted 5 wk including 2 wk of measurement (wk 4 and 5), during which intake was measured daily. In wk 4, daily methane emissions were quantified for 4 d using open circuit respiratory chambers. In wk 5, total tract digestibility, N balance, and urinary excretion of purine derivatives were determined from total feces and urine collected separately for 6 d. Ruminal fermentation products and protozoa concentration were analyzed from samples taken after morning feeding for 2 nonconsecutive days in wk 5. Tea saponin and nitrate supplementation decreased feed intake ( < 0.05), with an additive effect when fed in combination. Compared with CON, tea saponin did not modify methane emissions (g/kg DMI; > 0.05), whereas nitrate-containing diets (NIT and TEA+NIT) decreased methanogenesis by 28%, on average ( < 0.001). Total tract digestibility, N balance, and urinary excretion of purine derivatives were similar among diets. Ruminal fermentation products were not affected by tea saponin, whereas nitrate-containing diets increased acetate proportion and decreased butyrate proportion and ammonia concentration ( < 0.05). Under the experimental conditions tested, we confirmed the antimethanogenic effect of nitrate, whereas tea saponin alone included in pelleted concentrates failed to decrease enteric methane emissions in nonlactating dairy cows.

Infection and stillbirth.

PubMed

McClure, Elizabeth M; Goldenberg, Robert L

2009-08-01

Infection may cause stillbirth by several mechanisms, including direct infection, placental damage, and severe maternal illness. Various organisms have been associated with stillbirth, including many bacteria, viruses, and protozoa. In developed countries, between 10% and 25% of stillbirths may be caused by an infection, whereas in developing countries, which have much higher stillbirth rates, the contribution of infection is much greater. In developed countries, ascending bacterial infection, both before and after membrane rupture, with organisms such as Escherichia coli, group B streptococci, and Ureaplasma urealyticum is usually the most common infectious cause of stillbirth. However, in areas where syphilis is prevalent, up to half of all stillbirths may be caused by this infection alone. Malaria may be an important cause of stillbirth in women infected for the first time in pregnancy. The two most important viral causes of stillbirth are parvovirus and Coxsackie virus, although a number of other viral infections appear to be causal. Toxoplasma gondii, Listeria monocytogenes, and the organisms that cause leptospirosis, Q fever, and Lyme disease have all been implicated as etiologic for stillbirth. In certain developing countries, the stillbirth rate is high and the infection-related component so great that achieving a substantial reduction in stillbirth should be possible by reducing maternal infections. However, because infection-related stillbirth is uncommon in developed countries, and because those that do occur are caused by a wide variety of organisms, reducing this etiologic component of stillbirth much further will be difficult.

Dynamics of genome change among Legionella species

PubMed Central

Joseph, Sandeep J.; Cox, Daniel; Wolff, Bernard; Morrison, Shatavia S.; Kozak-Muiznieks, Natalia A.; Frace, Michael; Didelot, Xavier; Castillo-Ramirez, Santiago; Winchell, Jonas; Read, Timothy D.; Dean, Deborah

2016-01-01

Legionella species inhabit freshwater and soil ecosystems where they parasitize protozoa. L. pneumonphila (LP) serogroup-1 (Lp1) is the major cause of Legionnaires’ Disease (LD), a life-threatening pulmonary infection that can spread systemically. The increased global frequency of LD caused by Lp and non-Lp species underscores the need to expand our knowledge of evolutionary forces underlying disease pathogenesis. Whole genome analyses of 43 strains, including all known Lp serogroups 1–17 and 17 emergent LD-causing Legionella species (of which 33 were sequenced in this study) in addition to 10 publicly available genomes, resolved the strains into four phylogenetic clades along host virulence demarcations. Clade-specific genes were distinct for genetic exchange and signal-transduction, indicating adaptation to specific cellular and/or environmental niches. CRISPR spacer comparisons hinted at larger pools of accessory DNA sequences in Lp than predicted by the pan-genome analyses. While recombination within Lp was frequent and has been reported previously, population structure analysis identified surprisingly few DNA admixture events between species. In summary, diverse Legionella LD–causing species share a conserved core-genome, are genetically isolated from each other, and selectively acquire genes with potential for enhanced virulence. PMID:27633769

An Integrated Approach to Control Soil-Transmitted Helminthiasis, Schistosomiasis, Intestinal Protozoa Infection, and Diarrhea: Protocol for a Cluster Randomized Trial.

PubMed

Raso, Giovanna; Essé, Clémence; Dongo, Kouassi; Ouattara, Mamadou; Zouzou, Fabien; Hürlimann, Eveline; Koffi, Veronique A; Coulibaly, Gaoussou; Mahan, Virginie; Yapi, Richard B; Koné, Siaka; Coulibaly, Jean Tenena; Meïté, Aboulaye; Guéhi-Kabran, Marie-Claire; Bonfoh, Bassirou; N'Goran, Eliézer Kouakou; Utzinger, Jürg

2018-06-12

The global strategy to control helminthiases (schistosomiasis and soil-transmitted helminthiasis) emphasizes preventive chemotherapy. However, in the absence of access to clean water, improved sanitation, and adequate hygiene, reinfection after treatment can occur rapidly. Integrated approaches might be necessary to sustain the benefits of preventive chemotherapy and make progress toward interruption of helminthiases transmission. The aim of this study was to assess and quantify the effect of an integrated control package that consists of preventive chemotherapy, community-led total sanitation, and health education on soil-transmitted helminthiasis, schistosomiasis, intestinal protozoa infection, and diarrhea in rural Côte d'Ivoire. In a first step, a community health education program was developed that includes an animated cartoon to promote improved hygiene and health targeting school-aged children, coupled with a health education theater for the entire community. In a second step, a cluster randomized trial was implemented in 56 communities of south-central Côte d'Ivoire with 4 intervention arms: (1) preventive chemotherapy; (2) preventive chemotherapy plus community-led total sanitation; (3) preventive chemotherapy plus health education; and (4) all 3 interventions combined. Before implementation of the aforementioned interventions, a baseline parasitologic, anthropometric, and hygiene-related knowledge, attitudes, practices, and beliefs survey was conducted. These surveys were repeated 18 and 39 months after the baseline cross-sectional survey to determine the effect of different interventions on helminth and intestinal protozoa infection, nutritional indicators, and knowledge, attitudes, practices, and beliefs. Monitoring of diarrhea was done over a 24-month period at 2-week intervals, starting right after the baseline survey. Key results from this cluster randomized trial will shed light on the effect of integrated approaches consisting of preventive chemotherapy, community-led total sanitation, and health education against infections with soil-transmitted helminths, schistosomes, an intestinal protozoa and prevention of diarrhea in a rural part of Côte d'Ivoire. The research provided new insights into the acceptability, strengths, and limitations of an integrated community-based control package targeting helminthiases, intestinal protozoa infections, and diarrhea in rural communities of Côte d'Ivoire. In the longer term, the study will allow determining the effect of the integrated control approach on infection patterns with parasitic worms and intestinal protozoa, diarrheal incidence, anthropometric measures, and hygiene-related knowledge, attitudes, practices, and beliefs. International Standard Randomized Controlled Trial Number (ISRCTN): 53102033; http://www.isrctn.com/ISRCTN53102033 (Archived by WebCite at http://www.webcitation.org/6wpnXEiHo). RR1-10.2196/9166. ©Giovanna Raso, Clémence Essé, Kouassi Dongo, Mamadou Ouattara, Fabien Zouzou, Eveline Hürlimann, Veronique A Koffi, Gaoussou Coulibaly, Virginie Mahan, Richard B Yapi, Siaka Koné, Jean Tenena Coulibaly, Aboulaye Meïté, Marie-Claire Guéhi-Kabran, Bassirou Bonfoh, Eliézer Kouakou N'Goran, Jürg Utzinger. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 12.06.2018.

Quasi-phase matching and quantum control of high harmonic generation in waveguides using counterpropagating beams

DOEpatents

Zhang, Xiaoshi; Lytle, Amy L.; Cohen, Oren; Kapteyn, Henry C.; Murnane, Margaret M.

2010-11-09

All-optical quasi-phase matching (QPM) uses a train of counterpropagating pulses to enhance high-order harmonic generation (HHG) in a hollow waveguide. A pump pulse enters one end of the waveguide, and causes HHG in the waveguide. The counterpropagation pulses enter the other end of the waveguide and interact with the pump pulses to cause QPM within the waveguide, enhancing the HHG.

Construction of recombinant Newcastle disease virus expressing the S1 protein of Turkey enteric coronavirus for use as a bivalent vaccine

USDA-ARS?s Scientific Manuscript database

Turkey enteric coronavirus (TCoV) causes a contagious form of enteritis in turkeys, generally recognized in the field by outward signs including diarrhea and decreased weight gain, resulting in severe economic losses for the poultry industry in the US. To date there is no commercial vaccine availab...

Animal, Microbial, and Fungal Borne Skin Pathology in the Mountain Wilderness: A Review.

PubMed

Brandenburg, William E; Levandowski, William; Califf, Tom; Manly, Cory; Levandowski, Cecilia Blair

2017-06-01

Mountains are home to numerous organisms known to cause skin disease. Bites, stings, poisons, chemicals, toxins, trauma, and infections all contribute to this end. Numerous plants, animals, fungi, bacteria, viruses, and protozoa are responsible. This paper aims to review skin illness and injury sustained from organisms in the mountains of North America. Other factors such as increased ultraviolet radiation, temperature extremes, and decreasing atmospheric pressure along with human physiologic parameters, which contribute to disease severity, will also be discussed. After reading this review, one should feel more comfortable identifying potentially harmful organisms, as well as diagnosing, treating, and preventing organism-inflicted skin pathology sustained in the high country. Copyright © 2017 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

Peptidylprolyl cis-trans isomerases of Legionella pneumophila: virulence, moonlighting and novel therapeutic targets.

PubMed

Rasch, Janine; Ünal, Can M; Steinert, Michael

2014-12-01

Legionella pneumophila, typically a parasite of free-living protozoa, can also replicate in human alveolar macrophages and lung epithelial cells causing Legionnaires' disease in humans, a severe atypical pneumonia. The pathogen encodes six peptidylprolyl cis-trans isomerases (PPIases), which generally accelerate folding of prolyl peptide bonds, and influence protein folding. PPIases can be divided into three classes, cyclophilins, parvulins and FK506-binding proteins (FKBPs). They contribute to a multitude of cellular functions including bacterial virulence. In the present review, we provide an overview of L. pneumophila PPIases, discussing their known and anticipated functions as well as moonlighting phenomena. By taking the example of the macrophage infectivity potentiator (Mip) of L. pneumophila, we highlight the potential of PPIases as promising drug targets.

Differential Responses of Cecal Microbiota to Fishmeal, Eimeria and Clostridium perfringens in a Necrotic Enteritis Challenge Model in Chickens

PubMed Central

Rodgers, Nicholas; Swick, Robert A.; Moore, Robert J.

2014-01-01

Clostridium perfringens causes enteric diseases in animals and humans. In poultry, avian-specific C. perfringens strains cause necrotic enteritis, an economically significant poultry disease that costs the global industry over $2 billion annually in losses and control measures. With removal of antibiotic growth promoters in some countries this disease appears to be on the rise. In experimental conditions used to study disease pathogenesis and potential control measures, reproduction of the disease relies on the use of predisposing factors such as Eimeria infection and the use of high protein diets, indicating complex mechanisms involved in the onset of necrotic enteritis. The mechanisms by which the predisposing factors contribute to disease progression are not well understood but it has been suggested that they may cause perturbations in the microbiota within the gastrointestinal tract. We inspected changes in cecal microbiota and short chain fatty acids (SCFA) induced by Eimeria and fishmeal, in birds challenged or not challenged with C. perfringens. C. perfringens challenge in the absence of predisposing factors did not cause significant changes in either the alpha or beta diversity of the microbiota nor in concentrations of SCFA. Moreover, there was no C. perfringens detected in the cecal microbiota 2 days post-challenge without the presence of predisposing factors. In contrast, both fishmeal and Eimeria caused significant changes in microbiota, seen in both alpha and beta diversity and also enabled C. perfringens to establish itself post challenge. Eimeria had its strongest influence on intestinal microbiota and SCFA when combined with fishmeal. Out of 6 SCFAs measured, including butyric acid, none were significantly influenced by C. perfringens, but their levels were strongly modified following the use of both predisposing factors. There was little overlap in the changes caused following Eimeria and fishmeal treatments, possibly indicating multiple routes for progressing towards clinical symptoms of necrotic enteritis. PMID:25167074

Prevalence of pathogenic free-living amoeba and other protozoa in natural and communal piped tap water from Queen Elizabeth protected area, Uganda.

PubMed

Sente, Celsus; Erume, Joseph; Naigaga, Irene; Mulindwa, Julius; Ochwo, Sylvester; Magambo, Phillip Kimuda; Namara, Benigna Gabriela; Kato, Charles Drago; Sebyatika, George; Muwonge, Kevin; Ocaido, Michael

2016-08-03

Pathogenic water dwelling protozoa such as Acanthamoeba spp., Hartmannella spp., Naegleria spp., Cryptosporidium spp. and Giardia spp. are often responsible for devastating illnesses especially in children and immunocompromised individuals, yet their presence and prevalence in certain environment in sub-Saharan Africa is still unknown to most researchers, public health officials and medical practitioners. The objective of this study was to establish the presence and prevalence of pathogenic free-living amoeba (FLA), Cryptosporidium and Giardia in Queen Elizabeth Protected Area (QEPA). Samples were collected from communal taps and natural water sites in QEPA. Physical water parameters were measured in situ. The samples were processed to detect the presence of FLA trophozoites by xenic cultivation, Cryptosporidium oocysts by Ziehl-Neelsen stain and Giardia cysts by Zinc Sulphate floatation technique. Parasites were observed microscopically, identified, counted and recorded. For FLA, genomic DNA was extracted for amplification and sequencing. Both natural and tap water sources were contaminated with FLA, Cryptosporidium spp. and Giardia spp. All protozoan parasites were more abundant in the colder rainy season except for Harmannella spp. and Naegleria spp. which occurred more in the warmer months. The prevalence of all parasites was higher in tap water than in natural water samples. There was a strong negative correlation between the presence of Acanthamoeba spp., Hartmannella spp., Cryptosporidium spp. and Giardia spp. with Dissolved Oxygen (DO) (P < 0.05). The presence of Cryptosporidium spp. showed a significant positive correlation (P < 0.05) with conductivity, pH and Total Dissolved Solids (TDS); whereas the presence of Giardia spp. had only a strong positive correlation with TDS. Molecular genotyping of FLA produced 7 Acanthamoeba, 5 Echinamoeba, 2 Hartmannella, 1 Bodomorpha, 1 Nuclearia and 1 Cercomonas partial sequences. All water collection sites were found to be contaminated with pathogenic protozoa that could possibly be the cause of a number of silent morbidities and mortalities among rural households in QEPA. This implies that water used by communities in QEPA is of poor quality and predisposes them to a variety of protozoan infections including the FLA whose public health importance was never reported, thus necessitating adoption of proper water safety measures.

OCCURRENCE OF ENTERIC VIRUSES IN WATERS

EPA Science Inventory

A number of different types of human enteric viruses cause waterborne outbreaks when individuals are exposed to contaminated drinking and recreational waters. Vaccination against poliovirus has virtually eliminated poliomyelitis from the planet, but other members of the enterovi...

Biosecurity practices and causes of enteritis on Ontario meat rabbit farms

PubMed Central

Kylie, Jennifer; Brash, Marina; Whiteman, Ashley; Tapscott, Brian; Slavic, Durda; Weese, J. Scott; Turner, Patricia V.

2017-01-01

Infectious enterocolitis is a significant cause of mortality in meat rabbits. Disease risk is enhanced by intensive rearing practices and poor on-farm biosecurity. This investigation was undertaken in farmed meat rabbits during an Ontario-wide outbreak of enteritis with high mortality to determine the prevalence of causative agents. A survey evaluating on-farm biosecurity practices was also conducted to identify potential means of pathogen contamination and zoonotic risks. Gross and microscopic pathology evaluations combined with microbiologic testing were conducted on 95 rabbits over spring and winter months. Escherichia coli and Clostridium spiroforme were most commonly associated with enteritis in rabbits regardless of age or season and lesions were significantly more severe in mature does (P < 0.0001). The survey results demonstrated a lack of consistent on-farm biosecurity practices. The infectious nature of enteric disease of rabbits combined with poor biosecurity practices may contribute to disease transmission within and between farms. PMID:28588327

Biosecurity practices and causes of enteritis on Ontario meat rabbit farms.

PubMed

Kylie, Jennifer; Brash, Marina; Whiteman, Ashley; Tapscott, Brian; Slavic, Durda; Weese, J Scott; Turner, Patricia V

2017-06-01

Infectious enterocolitis is a significant cause of mortality in meat rabbits. Disease risk is enhanced by intensive rearing practices and poor on-farm biosecurity. This investigation was undertaken in farmed meat rabbits during an Ontario-wide outbreak of enteritis with high mortality to determine the prevalence of causative agents. A survey evaluating on-farm biosecurity practices was also conducted to identify potential means of pathogen contamination and zoonotic risks. Gross and microscopic pathology evaluations combined with microbiologic testing were conducted on 95 rabbits over spring and winter months. Escherichia coli and Clostridium spiroforme were most commonly associated with enteritis in rabbits regardless of age or season and lesions were significantly more severe in mature does ( P < 0.0001). The survey results demonstrated a lack of consistent on-farm biosecurity practices. The infectious nature of enteric disease of rabbits combined with poor biosecurity practices may contribute to disease transmission within and between farms.

21 CFR 520.2345c - Tetracycline boluses.

Code of Federal Regulations, 2012 CFR

2012-04-01

... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia caused by Pasteurella spp... doses. (i) Indications for use. Treatment of bacterial pneumonia caused by organisms susceptible to...

21 CFR 520.2345c - Tetracycline boluses.

Code of Federal Regulations, 2013 CFR

2013-04-01

... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia caused by Pasteurella spp... doses. (i) Indications for use. Treatment of bacterial pneumonia caused by organisms susceptible to...

21 CFR 520.2345c - Tetracycline boluses.

Code of Federal Regulations, 2014 CFR

2014-04-01

... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia caused by Pasteurella spp... doses. (i) Indications for use. Treatment of bacterial pneumonia caused by organisms susceptible to...

Parasitic pulmonary eosinophilia.

PubMed

Chitkara, Rajinder K; Krishna, Ganesh

2006-04-01

Parasitic infections, although common in tropical and subtropical regions, are prevalent worldwide because of changing immigration patterns and in international travel. The burden of worm infection is enormous and the intensity of infection is usually high among the poor and in immunocompromised individuals. Pulmonary eosinophilia occurs in almost all metazoan infections. In the Western world, the most common infections are caused by Strongyloides, Ascaris, Toxocara, and Ancylostoma species. Most of the nematodes multiply within the human host and cause pulmonary eosinophilia during larval migration through the lungs. Despite larval migration through the lungs, there is usually no permanent lung damage. The result is an increased number of eosinophils in the airways or lung parenchyma with or without peripheral eosinophilia. Löffler's syndrome, visceral larva migrans, and tropical pulmonary eosinophilia are the most common infections that cause pulmonary eosinophilia. The most serious parasitic eosinophilic lung disease is tropical pulmonary eosinophilia, a disorder caused by the filarial worms Wuchereria bancrofti and Brugia malayi, in which cases have typically been reported to masquerade acute or refractory bronchial asthma. Increasing awareness, newer diagnostic techniques, preventative measures, and antiparasitic drugs are important in reducing the worldwide morbidity and mortality from parasitic helminths and protozoa. This review focuses on common and some uncommon causes of pulmonary parasitic eosinophilia and their manifestations, diagnosis, and management.

[Clinical Characteristics of Metronidazole-induced Encephalopathy: A Report of Two Cases and a Review of 32 Japanese Cases in the Literature].

PubMed

Kato, Hideaki; Sosa, Hiroko; Mori, Masaaki; Kaneko, Takeshi

2015-09-01

Metronidazole is an antibiotic classically used against most anaerobic bacteria and protozoa. Because an intravenous form of metronidazole has recently entered the market, the use of this antibiotic is attracting renewed interest in many clinical settings in Japan. However, neurotoxicity is a major adverse event: in the central nervous system metronidazole-induced encephalopathy is a rare but serious condition. We performed a literature review of 34 cases including 2 of our cases, 25 from domestic conference abstracts, and 7 cases presented in full research papers. The mean patient age was 64.7 years. The conditions most commonly treated with metronidazole were brain abscess (35.3%), liver abscess (17.6%), and Clostridium difficile infection (14.7%). The most common predisposing conditions were liver dysfunction (26.5%), diabetes and other metabolic disorders (20.6%), and hematologic or solid organ malignancy (14.7%). The mean period of administration before the onset of encephalopathy symptoms was 61.3 days, and the mean total dose was 95.9g. The initial chief complaints were dysarthria (in 70.6% of the cases) and ataxia (61.8%); 82.4% of the cases were diagnosed on the basis of MRI (T2-weighted or FLAIR imaging). The key imaging finding was high intensity in the dentate nucleus bilaterally (82.4%). Stopping the metronidazole led to symptom remission within 8.5 days, but the MRI changes remained longer than the clinical symptoms. Two patients (6.0%) developed irreversible disturbance of consciousness. Although the mechanisms of this type of encephalopathy have not yet been elucidated, localized nerve-cell edema is likely caused by decreased metronidazole metabolism associated with liver and metabolic dysfunction. Careful observation for neurologic signs should be conducted during the treatment of brain abscesses associated with metronidazole administration, because patients with brain abscesses are naturally at high risk of metronidazole-induced encephalopathy.

Occurrence and Control of Legionella in Recycled Water Systems

PubMed Central

Jjemba, Patrick K.; Johnson, William; Bukhari, Zia; LeChevallier, Mark W.

2015-01-01

Legionella pneumophila is on the United States Environmental Protection Agency (USEPA) Candidate Contaminant list (CCL) as an important pathogen. It is commonly encountered in recycled water and is typically associated with amoeba, notably Naegleria fowleri (also on the CCL) and Acanthamoeba sp. No legionellosis outbreak has been linked to recycled water and it is important for the industry to proactively keep things that way. A review was conducted examine the occurrence of Legionella and its protozoa symbionts in recycled water with the aim of developing a risk management strategy. The review considered the intricate ecological relationships between Legionella and protozoa, methods for detecting both symbionts, and the efficacy of various disinfectants. PMID:26140674

ICTV Virus Taxonomy Profile: Partitiviridae.

PubMed

Vainio, Eeva J; Chiba, Sotaro; Ghabrial, Said A; Maiss, Edgar; Roossinck, Marilyn; Sabanadzovic, Sead; Suzuki, Nobuhiro; Xie, Jiatao; Nibert, Max; Ictv Report Consortium

2018-01-01

The Partitiviridae is a family of small, isometric, non-enveloped viruses with bisegmented double-stranded (ds) RNA genomes of 3-4.8 kbp. The two genome segments are individually encapsidated. The family has five genera, with characteristic hosts for members of each genus: either plants or fungi for genera Alphapartitivirus and Betapartitivirus, fungi for genus Gammapartitivirus, plants for genus Deltapartitivirus and protozoa for genus Cryspovirus. Partitiviruses are transmitted intracellularly via seeds (plants), oocysts (protozoa) or hyphal anastomosis, cell division and sporogenesis (fungi); there are no known natural vectors. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the taxonomy of the Partitiviridae, which is available at www.ictv.global/report/partitiviridae.

Gastric cryptosporidiosis in freshwater angelfish (Pterophyllum scalare)

USGS Publications Warehouse

Murphy, B.G.; Bradway, D.; Walsh, T.; Sanders, G.E.; Snekvik, K.

2009-01-01

A freshwater angelfish (Pterophyllum scalare) hatchery experienced variable levels of emaciation, poor growth rates, swollen coelomic cavities, anorexia, listlessness, and increased mortality within their fish. Multiple chemotherapeutic trials had been attempted without success. In affected fish, large numbers of protozoa were identified both histologically and ultrastructurally associated with the gastric mucosa. The youngest cohort of parasitized fish was the most severely affected and demonstrated the greatest morbidity and mortality. The protozoa were morphologically most consistent with Cryptosporidium. All of the protozoan life stages were identified ultrastructurally and protozoal genomic DNA was isolated from parasitized tissue viscera and sequenced. Histological, ultrastructural, genetic, and phylogenetic analyses confirmed this protozoal organism to be a novel species of Cryptosporidium.

Molecular screening for bacteria and protozoa in great cormorants (Phalacrocorax carbo sinensis) nesting in Slovakia, central Europe.

PubMed

Víchová, Bronislava; Reiterová, Katarína; Špilovská, Silvia; Blaňarová, Lucia; Hurníková, Zuzana; Turčeková, Ĺudmila

2016-09-01

This study brings the data about the occurrence of bacterial and protozoan pathogens in 32 great cormorants (Phalacrocorax carbo sinensis), representing approximately 20% of the population nesting in the surroundings of water basin Liptovská Mara (northern part of Central Slovakia). A survey revealed the presence of tick-borne bacteria Anaplasma phagocytophilum (6.25%) and parasitic protozoa Toxoplasma gondii (3.1%). These data indicate an infectious status of the great cormorant population nesting in Slovakia; they might suggest a degree of environmental contamination by infectious agents and demonstrate the role of migratory seabirds in the circulation and dispersal of pathogens with zoonotic potential.

Long-term Spatial Distribution Patterns of Protozoa in Connected Microhabitats

NASA Astrophysics Data System (ADS)

Taghon, G. L.; Tuorto, S. J.

2016-02-01

Studies of microbial ecosystems usually assume habitat homogeneity. Recent research, however, indicates that habitat structure varies at millimeter scales and that this patchiness affects abundance and behavior of microbes. In this study, two species of ciliated protozoa were maintained, together, for multiple generations in microfluidic devices consisting of arrays of interconnected microhabitats with differing resource availability. The species differed in their population dynamics and tendency to disperse among microhabitats. Both species coexisted for over 45 days, and their coexistence likely resulted from habitat selection at millimeter scales. We demonstrate that it is not only possible, but imperative, that detailed ecological phenomena of microbial systems be studied at the relevant spatial and temporal scales.

Application of in-situ hybridization for the detection and identification of avian malaria parasites in paraffin wax-embedded tissues from captive penguins

PubMed Central

Dinhopl, Nora; Mostegl, Meike M.; Richter, Barbara; Nedorost, Nora; Maderner, Anton; Fragner, Karin; Weissenböck, Herbert

2011-01-01

In captive penguins, avian malaria due to Plasmodium parasites is a well-recognized disease problem as these protozoa may cause severe losses among valuable collections of zoo birds. In blood films from naturally infected birds, identification and differentiation of malaria parasites based on morphological criteria are difficult because parasitaemia is frequently light and blood stages, which are necessary for identification of parasites, are often absent. Post-mortem diagnosis by histological examination of tissue samples is sometimes inconclusive due to the difficulties in differentiating protozoal tissue stages from fragmented nuclei in necrotic tissue. The diagnosis of avian malaria would be facilitated by a technique with the ability to specifically identify developmental stages of Plasmodium in tissue samples. Thus, a chromogenic in-situ hybridization (ISH) procedure with a digoxigenin-labelled probe, targeting a fragment of the 18S rRNA, was developed for the detection of Plasmodium parasites in paraffin wax-embedded tissues. This method was validated in comparison with traditional techniques (histology, polymerase chain reaction), on various tissues from 48 captive penguins that died at the zoological garden Schönbrunn, Vienna, Austria. Meronts of Plasmodium gave clear signals and were easily identified using ISH. Potential cross-reactivity of the probe was ruled out by the negative outcome of the ISH against a number of protozoa and fungi. Thus, ISH proved to be a powerful, specific and sensitive tool for unambiguous detection of Plasmodium parasites in paraffin wax-embedded tissue samples. PMID:21711191

Long-term exposure of bacterial and protozoan communities to TiO2 nanoparticles in an aerobic-sequencing batch reactor

NASA Astrophysics Data System (ADS)

Supha, Chitpisud; Boonto, Yuphada; Jindakaraked, Manee; Ananpattarachai, Jirapat; Kajitvichyanukul, Puangrat

2015-06-01

Titanium dioxide (TiO2) nanopowders at different concentrations (0-50 mg L-1) were injected into an aerobic-sequencing batch reactor (SBR) to investigate the effects of long-term exposure to nanoparticles on bacterial and protozoan communities. The detection of nanoparticles in the bioflocs was analyzed by scanning electron microscopy, transmission electron microscopy, and energy-dispersive x-ray spectroscopy. The SBR wastewater experiments were conducted under the influence of ultraviolet light with photocatalytic TiO2. The intrusion of TiO2 nanoparticles was found both on the surface and inside of the bioflocs. The change of microbial population in terms of mixed liquor-suspended solids and the sludge volume index was monitored. The TiO2 nanoparticles tentatively exerted an adverse effect on the microbial population, causing the reduction of microorganisms (both bacteria and protozoa) in the SBR. The respiration inhibition rate of the bacteria was increased, and the viability of the microbial population was reduced at the high concentration (50 mg L-1) of TiO2. The decreasing number of protozoa in the presence of TiO2 nanoparticles during 20 days of treatment with 0.5 and 1.0 mg L-1 TiO2 is clearly demonstrated. The measured chemical oxygen demand (COD) in the effluent tends to increase with a long-term operation. The increase of COD in the system suggests a decrease in the efficiency of the wastewater treatment plant. However, the SBR can effectively remove the TiO2 nanoparticles (up to 50 mg L-1) from the effluent.

21 CFR 520.154a - Bacitracin methylene disalicylate.

Code of Federal Regulations, 2012 CFR

2012-04-01

... prevention of necrotic enteritis caused by Clostridium perfringens susceptible to bacitracin methylene.... perfringens susceptible to bacitracin methylene disalicylate. (B) Limitations. Prepare a fresh solution daily...) Indications for use. For prevention of ulcerative enteritis due to Clostridium colinum susceptible to...

Targeting channels and transporters in protozoan parasite infections

NASA Astrophysics Data System (ADS)

Meier, Anna; Erler, Holger; Beitz, Eric

2018-03-01

Infectious diseases caused by pathogenic protozoa are among the most significant causes of death in humans. Therapeutic options are scarce and massively challenged by the emergence of resistant parasite strains. Many of the current anti-parasite drugs target soluble enzymes, generate unspecific oxidative stress, or act by an unresolved mechanism within the parasite. In recent years, collections of drug-like compounds derived from large-scale phenotypic screenings, such as the malaria or pathogen box, have been made available to researchers free of charge boosting the identification of novel promising targets. Remarkably, several of the compound hits have been found to inhibit membrane proteins at the periphery of the parasites, i.e. channels and transporters for ions and metabolites. In this review, we will focus on the progress made on targeting channels and transporters at different levels and the potential for use against infections with apicomplexan parasites mainly Plasmodium spp. (malaria) and Toxoplasma gondii (toxoplasmosis), with kinetoplastids Trypanosoma brucei (sleeping sickness), Trypanosoma cruzi (Chagas disease) and Leishmania ssp. (leishmaniasis), and the amoeba Entamoeba histolytica (amoebiasis).

The protozoan diseases of hatchery fish

USGS Publications Warehouse

Fish, F.F.

1935-01-01

Following the somewhat bleak picture painted in the consideration of the bacterial diseases of hatchery fish in the last number of The Progressive Fish Culturist, it is a relief to turn to another large group of fish diseases caused by small, single-celled parasitic animals known as the protozoa. To the hatcheryman, the protozoan diseases of fish are just as important as the bacterial diseases for they are equally destructive if allowed to run unchecked. The protozoan diseases are just as common as those caused by bacteria, particularly at those hatcheries which depend upon lakes or streams for their water supplies. However, a very cheery point of difference exists between these two groups of diseases—the protozoan diseases are easier to recognize and, for the most part, they are exceedingly easy to eradicate. To the hatcheryman who has struggled day and night for weeks in an attempt to combat an epidemic wherein he is rewarded immediately by the satisfying sight of a complete recovery of his infected fish as the direct result of his labors.

Alternative Host Models for Testing Anti-Protozoal or Antifungal Compounds and Fungal Infection.

PubMed

Torrecilhas, Ana Claudia; Xander, Patricia; Ferreira, Karen Spadari; Batista, Wagner Luiz

2018-01-01

The neglected tropical diseases (NTDs) are caused by several parasites, fungi, bacteria and viruses and affect more than one billion people in the world. The control and prevention against NTDs need implementation of alternative methods for testing new compounds against these diseases. For the implementation of alternative methods, it is necessary to apply the principles of replacement, reduction and refinement (the 3Rs) for the use of laboratory animals. Accordingly, the present review addressed a variety of alternative models to study the infections caused by protozoa and fungi. Overall, vertebrate and invertebrate models of fungal infection have been used to elucidate host-pathogen interactions. However, until now the insect model has not been used in protozoal studies as an alternative method, but there is interest in the scientific community to try new tools to screen alternative drugs to control and prevent protozoal infections. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Protozoan Cysts Act as a Survival Niche and Protective Shelter for Foodborne Pathogenic Bacteria

PubMed Central

Lambrecht, Ellen; Baré, Julie; Chavatte, Natascha; Bert, Wim; Sabbe, Koen

2015-01-01

The production of cysts, an integral part of the life cycle of many free-living protozoa, allows these organisms to survive adverse environmental conditions. Given the prevalence of free-living protozoa in food-related environments, it is hypothesized that these organisms play an important yet currently underinvestigated role in the epidemiology of foodborne pathogenic bacteria. Intracystic bacterial survival is highly relevant, as this would allow bacteria to survive the stringent cleaning and disinfection measures applied in food-related environments. The present study shows that strains of widespread and important foodborne bacteria (Salmonella enterica, Escherichia coli, Yersinia enterocolitica, and Listeria monocytogenes) survive inside cysts of the ubiquitous amoeba Acanthamoeba castellanii, even when exposed to either antibiotic treatment (100 μg/ml gentamicin) or highly acidic conditions (pH 0.2) and resume active growth in broth media following excystment. Strain- and species-specific differences in survival periods were observed, with Salmonella enterica surviving up to 3 weeks inside amoebal cysts. Up to 53% of the cysts were infected with pathogenic bacteria, which were located in the cyst cytosol. Our study suggests that the role of free-living protozoa and especially their cysts in the persistence and epidemiology of foodborne bacterial pathogens in food-related environments may be much more important than hitherto assumed. PMID:26070667

Isolation of new Brazilian giant viruses from environmental samples using a panel of protozoa.

PubMed

Dornas, Fábio P; Khalil, Jacques Y B; Pagnier, Isabelle; Raoult, Didier; Abrahão, Jônatas; La Scola, Bernard

2015-01-01

The Megavirales are a newly described order capable of infecting different types of eukaryotic hosts. For the most part, the natural host is unknown. Several methods have been used to detect these viruses, with large discrepancies between molecular methods and co-cultures. To isolate giant viruses, we propose the use of different species of amoeba as a cellular support. The aim of this work was to isolate new Brazilian giant viruses by comparing the protozoa Acanthamoeba castellanii, A. polyphaga, A. griffini, and Vermamoeba vermiformis (VV) as a platform for cellular isolation using environmental samples. One hundred samples were collected from 3 different areas in September 2014 in the Pampulha lagoon of Belo Horizonte city, Minas Gerais, Brazil. PCR was used to identify the isolated viruses, along with hemacolor staining, labelling fluorescence and electron microscopy. A total of 69 viruses were isolated. The highest ratio of isolation was found in A. polyphaga (46.38%) and the lowest in VV (0%). Mimiviruses were the most frequently isolated. One Marseillevirus and one Pandoravirus were also isolated. With Brazilian environmental samples, we demonstrated the high rate of lineage A mimiviruses. This work demonstrates how these viruses survive and circulate in nature as well the differences between protozoa as a platform for cellular isolation.

Removal of bacteria, protozoa and viruses through a multiple-barrier household water disinfection system.

PubMed

Espinosa-García, A C; Díaz-Ávalos, C; Solano-Ortiz, R; Tapia-Palacios, M A; Vázquez-Salvador, N; Espinosa-García, S; Sarmiento-Silva, R E; Mazari-Hiriart, M

2014-03-01

Municipal water disinfection systems in some areas are not always able to meet water consumer needs, such as ensuring distributed water quality, because household water management can be a contributing factor in water re-contamination. This fact is related to the storage options that are common in places where water is scarce or is distributed over limited time periods. The aim of this study is to assess the removal capacity of a multiple-barrier water disinfection device for protozoa, bacteria, and viruses. Water samples were taken from households in Mexico City and spiked with a known amount of protozoa (Giardia cyst, Cryptosporidium oocyst), bacteria (Escherichia coli), and viruses (rotavirus, adenovirus, F-specific ribonucleic acid (FRNA) coliphage). Each inoculated sample was processed through a multiple-barrier device. The efficiency of the multiple-barrier device to remove E. coli was close to 100%, and more than 87% of Cryptosporidium oocysts and more than 98% of Giardia cysts were removed. Close to 100% of coliphages were removed, 99.6% of the adenovirus was removed, and the rotavirus was almost totally removed. An effect of site by zone was detected; this observation is important because the water characteristics could indicate the efficiency of the multiple-barrier disinfection device.

A study of two U.S. Army installation drinking water sources and treatment systems for the removal of Giardia and Cryptosporidium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelley, M.B.; Brokaw, J.K.; Brokaw, J.K.

1996-11-01

This paper provides the results of a study of two U.S. Army installation drinking water sources and treatment systems for the removal of Giardia and Cryptosporidium. Sampling was conducted monthly for one year commencing in late March 1994 and concluding at the end of February 1995. Results of this detailed study include examination of turbidity, particle counts, and total and fecal coliforms as well as the enumeration of Giardia cysts and Cryptosporidium oocysts. Our goal, in addition to determining the levels of these pathogens in both raw and product waters, was to determine if typical operating parameters would be helpfulmore » in identifying either elevated raw water protozoa or breakthrough of either pathogen in the product water from the treatment facilities. A data summary for the results of the protozoa enumeration is a Table 1. Our results indicate frequent contamination of the raw waters at both sites by either or both pathogens. Further, we observed sporadic breakthrough of low levels of Cryptosporidium in the filtered waters of both sites. The method employed to concentrate, purify and enumerate the pathogenic protozoa is also discussed and comparisons are made to the proposed Information Collection Rule (ICR) method for detection of these microorganisms.« less

Molecular Detection of the Carriage Rate of Four Intestinal Protozoa with Real-Time Polymerase Chain Reaction: Possible Overdiagnosis of Entamoeba histolytica in Nigeria

PubMed Central

Efunshile, Michael A.; Ngwu, Bethrand A. F.; Kurtzhals, Jørgen A. L.; Sahar, Sumrin; König, Brigitte; Stensvold, Christen R.

2015-01-01

Diarrhea remains the second largest killer of children worldwide, and Nigeria ranks number two on the list of global deaths attributable to diarrhea. Meanwhile, prevalence studies on potentially diarrheagenic protozoa in asymptomatic carriers using molecular detection methods remain scarce in sub-Saharan countries. To overcome sensitivity issues related to microscopic detection and identification of cysts in stool concentrates, real-time polymerase chain reaction (PCR) was used to analyze genomic DNAs extracted from stool samples from 199 healthy school children for Entamoeba histolytica, E. dispar, Giardia intestinalis, and Cryptosporidium. Questionnaires were administered for epidemiological data collection. E. histolytica was not detected in any of the samples, whereas Giardia (37.2%), E. dispar (18.6%), and Cryptosporidium (1%) were found. Most of the children sourced their drinking water from community wells (91%), while the majority disposed of feces in the bush (81.9%). Our study is the first to use real-time PCR to evaluate the epidemiology of E. histolytica, Giardia, and Cryptosporidium in Nigeria where previous studies using traditional diagnostic techniques have suggested higher and lower carriage rates of E. histolytica and Giardia, respectively. It is also the first study to accurately identify the prevalence of common potentially diarrheagenic protozoa in asymptomatic carriers in sub-Saharan Africa. PMID:26101274

Coagulation, flocculation, dissolved air flotation and filtration in the removal of Giardia spp. and Cryptosporidium spp. from water supply.

PubMed

Andreoli, Fernando César; Sabogal-Paz, Lyda Patricia

2017-11-15

Removing protozoa from a water supply using coagulation, flocculation, dissolved air flotation (DAF) and filtration on a bench scale was evaluated. Calcium carbonate flocculation with and without immunomagnetic separation (IMS) was chosen to detect Giardia spp. cysts and Cryptosporidium spp. oocysts in the studied samples. The results indicated that DAF removed between 1.31 log and 1.79 log of cysts and between 1.08 log and 1.42 log of oocysts. The performance was lower in filtration, with the removal of 1.07 log-1.44 log for cysts and 0.82 log-0.98 log for oocysts. The coagulation, flocculation, DAF and filtration steps removed more than 2.2 log of cysts and oocysts from the water studied. However, protozoa were detected in the filtered water, even with turbidity values of 0.2 NTU. The recovery of the detection method met the international criteria and was higher when there was no IMS. Including the third acid dissociation in the IMS was critical to improve the performance of the protocol tested. However, there was an increase in the technical and analytical complexity and costs. It was also observed that the efficiency of the treatment was linked to the performance of the selected method of detecting protozoa.

Enteric virus and vibrio contamination of shellfish: intervention strategies

USDA-ARS?s Scientific Manuscript database

INTRODUCTION. Molluscan shellfish include oysters, clams, mussels, and cockles, which can cause illnesses from a variety of human pathogens. Enteric viruses, like norovirus and hepatitis A virus, are generally transmitted to shellfish through fecal contamination of shellfish harvesting areas, alth...

The Bernhard-Nocht-Institut fuer Schiffs- und Tropenkrankheiten Hamburg,

DTIC Science & Technology

PARASITES, *WORMS), (*PROTOZOA, PARASITES), (*PARASITIC DISEASES, TROPICAL REGIONS), DISEASES, FILARIAE, SCHISTOSOMA, INFECTIONS, GASTROPODA , AMOEBA, TRYPANOSOMA, LEISHMANIA, PARASITES, THERAPY, CHEMOTHERAPY, WEST GERMANY

Altered Protozoan and Bacterial Communities and Survival of Escherichia coli O157:H7 in Monensin-Treated Wastewater from a Dairy Lagoon

PubMed Central

Ravva, Subbarao V.; Sarreal, Chester Z.; Mandrell, Robert E.

2013-01-01

Surviving predation is a fitness trait of Escherichia coli O157:H7 (EcO157) that provides ample time for the pathogen to be transported from reservoirs (e.g. dairies and feedlots) to farm produce grown in proximity. Ionophore dietary supplements that inhibit rumen protozoa may provide such a selective advantage for EcO157 to proliferate in lagoons as the pathogen is released along with the undigested supplement as manure washings. This study evaluated the fate of an outbreak strain of EcO157, protozoan and bacterial communities in wastewater treated with monensin. Although total protozoa and native bacteria were unaffected by monensin, the time for 90% decrease in EcO157 increased from 0.8 to 5.1 days. 18S and 16S rRNA gene sequencing of wastewater samples revealed that monensin eliminated almost all colpodean and oligohymenophorean ciliates, probably facilitating the extended survival of EcO157. Total protozoan numbers remained high in treated wastewater as monensin enriched 94% of protozoan sequences undetected with untreated wastewater. Monensin stimulated 30-fold increases in Cyrtohymena citrina, a spirotrichean ciliate, and also biflagellate bicosoecids and cercozoans. Sequences of gram-negative Proteobacteria increased from 1% to 46% with monensin, but gram-positive Firmicutes decreased from 93% to 46%. It is noteworthy that EcO157 numbers increased significantly (P<0.01) in Sonneborn medium containing monensin, probably due to monensin-inhibited growth of Vorticella microstoma (P<0.05), a ciliate isolated from wastewater. We conclude that dietary monensin inhibits ciliate protozoa that feed on EcO157. Feed supplements or other methods that enrich these protozoa in cattle manure could be a novel strategy to control the environmental dissemination of EcO157 from dairies to produce production environments. PMID:23349969

Blood protozoa of free-living birds

USGS Publications Warehouse

Herman, C.M.; McDiarmid, Archibald

1969-01-01

Blood protozoa were first reported from wild birds in 1884. Since then numerous surveys throughout the world have demonstrated their presence in a wide variety of hosts and localities with continuing designations of new species. Taxonomic determinations include parasites in the genera Plasmodium, Haemoproteus, Leucocytozoon, Babesia, Lankesterella and Trypanosoma. Transmission of Plasmodium by mosquitoes was demonstrated with a bird parasite before these insects were proven as vectors of human malaria. All the genera under consideration require an insect vector to complete their life-cycles and susceptible vectors have been demonstrated. Most experimental work on the blood protozoa of birds has been carried on with captive birds. An extensive volume of research has been conducted on Plasmodium because of its close similarity to malaria in man. Field studies that would provide information on the epizootiology of occurrence of these parasites in wild populations have been very limited, mainly confined to single blood film surveys. Such data are inadequate to provide an understanding of true prevalence or incidence or of factual knowledge of their impact on the wild population. Mechanisms for procuring such information are available in some cases and can be developed to fit other situations. Isodiagnosis, inoculation of blood from wild birds into susceptible captive hosts, has revealed a prevalence of over 60 % for Plasmodium in situations where microscope examination of single peripheral blood preparations yielded less than 1 %. Culture of bone marrow collected by biopsy demonstrates high prevalence of trypanosomes even when none are evident from microscopic examination of blood. Often preparations of tissues collected at necropsy reveal Leucocytozoon and Lankesterella when examination of peripheral blood gave no indication of infection. Methods developed by bird ringers provide techniques for obtaining repeat examinations of free-living birds that can yield further pertinent data. The use that has been made of these techniques, beyond the mere procurement of a single blood film, is reviewed from the standpoint of providing knowledge of the epizootiology of the blood protozoa of birds and their further potential is projected.

Characterization of the efficiency and uncertainty of skimmed milk flocculation for the simultaneous concentration and quantification of water-borne viruses, bacteria and protozoa.

PubMed

Gonzales-Gustavson, Eloy; Cárdenas-Youngs, Yexenia; Calvo, Miquel; da Silva, Marcelle Figueira Marques; Hundesa, Ayalkibet; Amorós, Inmaculada; Moreno, Yolanda; Moreno-Mesonero, Laura; Rosell, Rosa; Ganges, Llilianne; Araujo, Rosa; Girones, Rosina

2017-03-01

In this study, the use of skimmed milk flocculation (SMF) to simultaneously concentrate viruses, bacteria and protozoa was evaluated. We selected strains of faecal indicator bacteria and pathogens, such as Escherichia coli and Helicobacter pylori. The viruses selected were adenovirus (HAdV 35), rotavirus (RoV SA-11), the bacteriophage MS2 and bovine viral diarrhoea virus (BVDV). The protozoa tested were Acanthamoeba, Giardia and Cryptosporidium. The mean recoveries with q(RT)PCR were 66% (HAdV 35), 24% (MS2), 28% (RoV SA-11), 15% (BVDV), 60% (E. coli), 30% (H. pylori) and 21% (Acanthamoeba castellanii). When testing the infectivity, the mean recoveries were 59% (HAdV 35), 12% (MS2), 26% (RoV SA-11) and 0.7% (BVDV). The protozoa Giardia lamblia and Cryptosporidium parvum were studied by immunofluorescence with recoveries of 18% and 13%, respectively. Although q(RT)PCR consistently showed higher quantification values (as expected), q(RT)PCR and the infectivity assays showed similar recoveries for HAdV 35 and RoV SA-11. Additionally, we investigated modelling the variability and uncertainty of the recovery with this method to extrapolate the quantification obtained by q(RT)PCR and estimate the real concentration. The 95% prediction intervals of the real concentration of the microorganisms inoculated were calculated using a general non-parametric bootstrap procedure adapted in our context to estimate the technical error of the measurements. SMF shows recoveries with a low variability that permits the use of a mathematical approximation to predict the concentration of the pathogen and indicator with acceptable low intervals. The values of uncertainty may be used for a quantitative microbial risk analysis or diagnostic purposes. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Eukaryotic inhibitors or activators elicit responses to chemosensory compounds by ruminal isotrichid and entodiniomorphid protozoa.

PubMed

Diaz, H L; Barr, K N; Godden, K R; Plank, J E; Zapata, I; Schappacher, A N; Wick, M P; Firkins, J L

2014-01-01

Our objectives were to evaluate potential signaling pathways regulating rumen protozoal chemotaxis using eukaryotic inhibitors potentially coordinated with phagocytosis as assessed by fluorescent bead uptake kinetics. Wortmannin (inhibitor of phosphoinositide 3-kinase), insulin, genistein (purported inhibitor of a receptor tyrosine kinase), U73122 (inhibitor of phospholipase C), and sodium nitroprusside (Snp, nitric oxide generator, activating protein kinase G) were preincubated with mixed ruminal protozoa for 3h before assessing uptake of fluorescent beads and chemosensory behavior to glucose, peptides, and their combination; peptides were also combined with guanosine triphosphate (GTP; a chemorepellent). Entodiniomorphids were chemoattracted to both glucose and peptides, but chemoattraction to glucose was increased by Snp and wortmannin without effect on chemoattraction to peptides. Rate of fluorescent bead uptake by an Entodinium caudatum culture decreased when beads were added simultaneously with feeding and incubated with wortmannin (statistical interaction). Wortmannin also decreased the proportion of mixed entodiniomorphids consuming beads. Isotrichid protozoa exhibited greater chemotaxis to glucose but, compared with entodiniomorphids, were chemorepelled to peptides. Wortmannin increased chemotaxis by entodiniomorphids but decreased chemotaxis to glucose by isotrichids. Motility assays documented that Snp and wortmannin decreased net swimming speed (distance among 2 points per second) but not total swimming speed (including turns) by entodiniomorphids. Wortmannin decreased both net and total swimming behavior in isotrichids. Results mechanistically explain the isotrichid migratory ecology to rapidly take up newly ingested sugars and subsequent sedimentation back to the ventral reticulorumen. In contrast, entodiniomorphids apparently integrate cellular motility with feeding behavior to consume small particulates and thereby stay associated and pass with the degradable fraction of rumen particulates. These results extend findings from aerobic ciliate models to explain how rumen protozoa have adapted physiology for their specific ecological niches. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of an integrated intervention package of preventive chemotherapy, community-led total sanitation and health education on the prevalence of helminth and intestinal protozoa infections in Côte d'Ivoire.

PubMed

Hürlimann, Eveline; Silué, Kigbafori D; Zouzou, Fabien; Ouattara, Mamadou; Schmidlin, Thomas; Yapi, Richard B; Houngbedji, Clarisse A; Dongo, Kouassi; Kouadio, Bernadette A; Koné, Siaka; Bonfoh, Bassirou; N'Goran, Eliézer K; Utzinger, Jürg; Acka-Douabélé, Cinthia A; Raso, Giovanna

2018-02-27

Preventive chemotherapy with donated anthelminthic drugs is the cornerstone for the control of helminthiases. However, reinfection can occur rapidly in the absence of clean water and sanitation coupled with unhygienic behaviour. The purpose of this study was to assess the effect of an integrated package of interventions, consisting of preventive chemotherapy, community-led total sanitation (CLTS) and health education, on the prevalence of helminth and intestinal protozoa infections and on participants' knowledge, attitude, practice and beliefs (KAPB) towards these diseases including water, sanitation and hygiene (WASH). A cross-sectional survey was carried out in nine communities of south-central Côte d'Ivoire to assess people's infection with helminths and intestinal protozoa and KAPB. Subsequently, interventions were targeted to five communities, while the remaining communities served as control. The intervention encouraged latrine construction and an evaluation was done 6-7 months later to determine open defecation status of the respective communities. Anthelminthic treatment was provided to all community members. A follow-up cross-sectional survey was conducted approximately one year later, using the same procedures. Overall, 810 people had complete baseline and follow-up data and were given anthelminthic treatment. The baseline prevalence of hookworm, Schistosoma haematobium, Trichuris trichiura, Schistosoma mansoni and Ascaris lumbricoides was 31.1%, 7.0%, 2.0%, 1.0% and 0.3%, respectively. Four of the five intervention communities were classified open-defecation free. For hookworm infection, we observed higher negative changes in terms of proportion of decrease (-0.10; 95% confidence interval (CI): - 0.16, -0.04) and higher egg reduction rate (64.9 vs 15.2%) when comparing intervention with control communities. For intestinal protozoa, prevalence reduction was higher in intervention compared to control communities (8.2 vs 2.6%) and WASH indicators and intervention outcomes associated with lower odds for infection at follow-up. The intervention significantly impacted on reported latrine use (before: 15.5%, after: 94.6%), open defecation in the community surroundings (before: 75.0%, after: 16.7%) and awareness for environmental contamination through open defecation (before: 20.4%, after: 52.2%). An integrated package of interventions consisting of preventive chemotherapy, health education and CLTS reduces the prevalence of helminth and intestinal protozoa infection. Additional studies in other social-ecological settings are warranted to confirm our findings.

Enviromental sanitation in urban and rural areas: its importance in the control of enteric infections.

PubMed

Wolman, A

1975-01-01

In Central and South America, enteric infections constitute one of the leading causes of disease and death. The terrible toll is exacted by a host of different microorganisms, virtually all of which are transmitted via contact with human excreta. To change this picture we need many more water supply and sewerage systems, better food preparation and handling, and public comprehension of how elementary good hygiene promotes good health. Attaining these objectives will be difficult, but less costly than one might suppose, and there is little to be gained by delay. The basic enviromental causes of enteric disease are clear, current conditions have been aggravated by rapid population growth and urbanization, and basic corrective measures have already been postponed long enough.

Socio-demographic, Clinical and Laboratory Features of Rotavirus Gastroenteritis in Children Treated in Pediatric Clinic

PubMed Central

Azemi, Mehmedali; Berisha, Majlinda; Ismaili-Jaha, Vlora; Kolgeci, Selim; Avdiu, Muharrem; Jakupi, Xhevat; Hoxha, Rina; Hoxha-Kamberi, Teuta

2013-01-01

Aim: The aim of work was presentation of several socio-demographic, clinical and laboratory characteristics of gastroenteritis caused by rotavirus. The examinees and methods: The examinees were children under the age of five years treated at the Pediatric Clinic due to acute gastroenteritis caused by rotavirus. Rotavirus is isolated by method chromatographic immunoassay by Cer Test Biotec. Results: From the total number of patients (850) suffering from acute gastroenteritis, feces test on bacteria, viruses. protozoa and fungi was positive in 425 (49.76%) cases. From this number the test on bacteria was positive in 248 (58.62%) cases, on viruses it was positive in 165 (39.0%), on protozoa in 9 (2.12%) cases and on fungi only one case. Rotavirus was the most frequent one in viral test, it was isolated in 142 (86.06%) cases, adenoviruses were found in 9 (5.45%) cases and noroviruses in only one case. The same feces sample that contained rotavirus and adenoviruses were isolated in five cases, whereas rotavirus with bacteria was isolated in the same feces sample in five cases. The biggest number of cases 62 (43.66%) were of the age 6-12 months, whereas the smallest number 10 (7.04%) cases were of the age 37-60 months. There were 76 (53.52%) of cases of male gender, from rural areas there were 81 (57.04%) cases and there were 58 (40.80%) cases during the summer period. Among the clinical symptoms the most prominent were diarrhea, vomiting, high temperature, whereas the different degree of dehydration were present in all cases (the most common one was moderate dehydration). The most frequent one was isonatremic dehydration in 91 (64.08%) cases, less frequent one was hypernatremic dehydration in 14 (9.85%) cases. The majority of cases (97.89%) had lower blood pH values, whereas 67 (47.17%) cases had pH values that varied from 7.16 -7.20 (curve peak), normal values were registered in only 3 (2.11%) cases. Urea values were increased in 45 (31.07%) cases (the maximum value was 26.5 mmol/L), whereas creatinine value was increased in 41 (28.87%) cases (maximum value was 302 mmol/L). Conclusion: The results show the high frequency of rotavirus infections in children hospitalized with acute gastroenteritis. Rotavirus may cause different dehydration degree with electrolyte, acid-base and other biochemical disorders. Preventing the infection caused by rotavirus is of a great importance. PMID:23678334

Space Station and the life sciences

NASA Technical Reports Server (NTRS)

White, R. J.; Leonard, J. I.; Cramer, D. B.; Bishop, W. P.

1983-01-01

Previous fundamental research in space life sciences is examined, and consideration is devoted to studies relevant to Space Station activities. Microgravity causes weight loss, hemoconcentration, and orthostatic intolerance when astronauts returns to earth. Losses in bone density, bone calcium, and muscle nitrogen have also been observed, together with cardiovascular deconditioning, fluid-electrolyte metabolism alteration, and space sickness. Experiments have been performed with plants, bacteria, fungi, protozoa, tissue cultures, invertebrate species, and with nonhuman vertebrates, showing little effect on simple cell functions. The Spacelab first flight will feature seven life science experiments and the second flight, two. Further studies will be performed on later flights. Continued life science studies to optimize human performance in space are necessary for the efficient operation of a Space Station and the assembly of large space structures, particularly in interaction with automated machinery.

Trypanosoma brucei eflornithine transporter AAT6 is a low-affinity low-selective transporter for neutral amino acids.

PubMed

Mathieu, Christoph; González Salgado, Amaia; Wirdnam, Corina; Meier, Stefan; Grotemeyer, Marianne Suter; Inbar, Ehud; Mäser, Pascal; Zilberstein, Dan; Sigel, Erwin; Bütikofer, Peter; Rentsch, Doris

2014-10-01

Amino acid transporters are crucial for parasite survival since the cellular metabolism of parasitic protozoa depends on the up-take of exogenous amino acids. Amino acid transporters are also of high pharmacological relevance because they may mediate uptake of toxic amino acid analogues. In the present study we show that the eflornithine transporter AAT6 from Trypanosoma brucei (TbAAT6) mediates growth on neutral amino acids when expressed in Saccharomyces cerevisiae mutants. The transport was electrogenic and further analysed in Xenopus laevis oocytes. Neutral amino acids, proline analogues, eflornithine and acivicin induced inward currents. For proline, glycine and tryptophan the apparent affinities and maximal transport rates increased with more negative membrane potentials. Proline-induced currents were dependent on pH, but not on sodium. Although proline represents the primary energy source of T. brucei in the tsetse fly, down-regulation of TbAAT6-expression by RNAi showed that in culture TbAAT6 is not essential for growth of procyclic form trypanosomes in the presence of glucose or proline as energy source. TbAAT6-RNAi lines of both bloodstream and procyclic form trypanosomes showed reduced susceptibility to eflornithine, whereas the sensitivity to acivicin remained unchanged, indicating that acivicin enters the cell by more than one transporter.

Development of a qualitative pathogen risk-assessment methodology for municipal-sludge landfilling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1988-04-01

This report addresses potential risks from microbiological pathogens present in municipal sludge disposal in landfills. Municipal sludges contain a wide variety of bacteria, viruses, protozoa, helminths, and fungi. Survival characteristics of pathogens are critical factors in assessing the risks associated with potential transport of microorganisms from the sludge-soil matrix to the ground-water environment of landfills. Various models are discussed for predicting microbial die-off. The order of persistence in the environment from longest to shortest survival time appears to be helminth eggs > viruses > bacteria > protozoan cysts. Whether or not a pathogen reaches ground-water and is transported to drinking-watermore » wells depends on a number of factors, including initial concentration of the pathogen, survival of the pathogen, number of pathogens that reach the sludge-soil interface, degree of removal through the unsaturated and saturated-soil zones, and the hydraulic gradient. The degree to which each of these factors will influence the probability of pathogens entering ground-water cannot be determined precisely. Information on the fate of pathogens at existing landfills is sorely lacking. Additional laboratory and field studies are needed to determine the degree of pathogen leaching, survival and transport in ground-water in order to estimate potential risks from pathogens at sludge landfills with reasonable validity.« less

Equine grass sickness, but not botulism, causes autonomic and enteric neurodegeneration and increases soluble N-ethylmaleimide-sensitive factor attachment receptor protein expression within neuronal perikarya.

PubMed

McGorum, B C; Scholes, S; Milne, E M; Eaton, S L; Wishart, T M; Poxton, I R; Moss, S; Wernery, U; Davey, T; Harris, J B; Pirie, R S

2016-11-01

Equine grass sickness (EGS) is of unknown aetiology. Despite some evidence suggesting that it represents a toxico-infection with Clostridium botulinum types C and/or D, the effect of EGS on the functional targets of botulinum neurotoxins, namely the soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins, is unknown. Further, while it is commonly stated that, unlike EGS, equine botulism is not associated with autonomic and enteric neurodegeneration, this has not been definitively assessed. To determine: 1) whether botulism causes autonomic and enteric neurodegeneration; and 2) the effect of EGS on the expression of SNARE proteins within cranial cervical ganglion (CCG) and enteric neuronal perikarya. Descriptive study. Light microscopy was used to compare the morphology of neurons in haematoxylin-eosin stained sections of CCG and ileum from 6 EGS horses, 5 botulism horses and 6 control horses. Immunohistochemistry was used to compare the expression of synaptosomal-associated protein-25, synaptobrevin (Syb) and syntaxin within CCG neurons, and of Syb in enteric neurons, from horses with EGS, horses with botulism and control horses. The concentrations of these SNARE proteins in extracts of CCG from EGS and control horses were compared using quantitative fluorescent western blotting. EGS, but not botulism, was associated with autonomic and enteric neurodegeneration and with increased immunoreactivity for SNARE proteins within neuronal perikarya. Quantitative fluorescent western blotting confirmed increased concentrations of synaptosomal-associated protein-25, Syb and syntaxin within CCG extracts from EGS vs. control horses, with the increases in the latter 2 proteins being statistically significant. The occurrence of autonomic and enteric neurodegeneration, and increased expression of SNARE proteins within neuronal perikarya, in EGS but not botulism, suggests that EGS may not be caused by botulinum neurotoxins. Further investigation of the aetiology of EGS is therefore warranted. © 2015 EVJ Ltd.

Medical Surveillance Monthly Report. olume 22, Number 1, January 2015

DTIC Science & Technology

2015-01-01

etiologic agents for enteric fever , the prototype of which is typhoid fever caused by S. Typhi.1 In the U.S., the most common serotypes isolated in...component of the U.S. Armed Forces, Sal- monella is a leading cause of acute gastroin- testinal illness.3 Typhoid fever , in contrast, is relatively...more than 20 million cases of typhoid fever occur annually and another 5.5 million cases of enteric fever are attributed to S. Paratyphi.1 Th e most

42 CFR 73.1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... (including, but not limited to, bacteria, viruses, fungi, rickettsiae, or protozoa), or infectious substance... product of plants, animals, microorganisms (including, but not limited to, bacteria, viruses, fungi...

42 CFR 73.1 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... (including, but not limited to, bacteria, viruses, fungi, rickettsiae, or protozoa), or infectious substance... product of plants, animals, microorganisms (including, but not limited to, bacteria, viruses, fungi...

42 CFR 73.1 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... (including, but not limited to, bacteria, viruses, fungi, rickettsiae, or protozoa), or infectious substance... product of plants, animals, microorganisms (including, but not limited to, bacteria, viruses, fungi...

Structure and biochemical characterization of proliferating cellular nuclear antigen from a parasitic protozoon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cardona-Felix, Cesar S.; Lara-Gonzalez, Samuel; Brieba, Luis G.

2012-02-08

Proliferating cellular nuclear antigen (PCNA) is a toroidal-shaped protein that is involved in cell-cycle control, DNA replication and DNA repair. Parasitic protozoa are early-diverged eukaryotes that are responsible for neglected diseases. In this work, a PCNA from a parasitic protozoon was identified, cloned and biochemically characterized and its crystal structure was determined. Structural and biochemical studies demonstrate that PCNA from Entamoeba histolytica assembles as a homotrimer that is able to interact with and stimulate the activity of a PCNA-interacting peptide-motif protein from E. histolytica, EhDNAligI. The data indicate a conservation of the biochemical mechanisms of PCNA-mediated interactions between metazoa, yeastmore » and parasitic protozoa.« less

Treatment of industrial effluents by a continuous system: electrocoagulation--activated sludge.

PubMed

Moisés, Tejocote-Pérez; Patricia, Balderas-Hernández; Barrera-Díaz, C E; Gabriela, Roa-Morales; Natividad-Rangel, Reyna

2010-10-01

A continuous system electrocoagulation--active sludge was designed and built for the treatment of industrial wastewater. The system included an electrochemical reactor with aluminum electrodes, a clarifier and a biological reactor. The electrochemical reactor was tested under different flowrates (50, 100 and 200 mL/min). In the biological reactor, the performance of different cultures of active sludge was assessed: coliform bacterial, ciliate and flagellate protozoa and aquatic fungus. Overall treatment efficiencies of color, turbidity and COD removal were 94%, 92% and 80%, respectively, under optimal conditions of 50 mL/min flowrate and using ciliate and flagellate protozoa. It was concluded that the system was efficient for the treatment of industrial wastewater. Copyright © 2010 Elsevier Ltd. All rights reserved.

Environmental enteric dysfunction is associated with carnitine deficiency and altered fatty acid oxidation

USDA-ARS?s Scientific Manuscript database

Environmental enteric dysfunction (EED), a condition characterized by small intestine inflammation and abnormal gut permeability, is widespread in children in developing countries and a major cause of growth failure. The pathophysiology of EED remains poorly understood. We measured serum metabolite...

Salmonella interactions with plants and their associated microbiota

USDA-ARS?s Scientific Manuscript database

The increase in the incidence of gastroenteritis outbreaks linked to the consumption of foods of plant origin has ignited public concern and scientific interest in understanding interactions of human enteric pathogens with plants. Enteric disease caused by non-typhoidal Salmonella is a major public ...

[Acute abdomen caused by eosinophilic enteritis: six observations].

PubMed

Martínez-Ubieto, Fernando; Bueno-Delgado, Alvaro; Jiménez-Bernadó, Teresa; Santero Ramírez, María Pilar; Arribas-Del Amo, Dolores; Martínez-Ubieto, Javier

2013-01-01

Eosinophilic enteritis is a rather rare condition characterized by infiltration of the gastrointestinal tract by eosinophils; as a casue of acute abdomen it is really exceptional. The etiology is unclear and its description in the literature is sparse, but associations have been made with collagen vascular disease, inflammatory bowel disease, food allergy and parasitic infections as it was confirmed in one of our pathologic studies. From 1997 to 2011 six cases of eosinophilic enteritis that involved a small bowel segment were diagnosed. A partial resection by an irreversible necrosis was necessary in three of them; in the other three only a biopsy was necessary due to the inflammatory aspect of the affected loop causing the acute abdomen. Eosinophilic enteritis can originate acute abdomen processes where an urgent surgical treatment is necessary. The intraoperative aspect can be from a segment of small bowel with inflammatory signs up to a completely irrecoverable loop, where removing of the affected segment is the correct treatment, which can be done laparoscopically.

[Outbreaks caused by diarrheagenic Escherichia coli].

PubMed

Vila Estapé, Jordi; Zboromyrska, Yuliya

2012-02-01

Escherichia coli are ubiquitous bacteria from a wide variety of ecosystems including the gastrointestinal tract of humans and warm-blooded animals. E. coli can play a role as an opportunistic bacteria causing a variety of infectious diseases including, among many others, sepsis, urinary tract infections, meningitis, and wound infections. Moreover, these bacteria can also act as primary pathogens in the intestinal tract. There are several pathotypes of E. coli that cause enteritis, and both sporadic cases and outbreaks have been reported. In this article, we review the pathogenicity and epidemiology of enteritis caused by these E. coli pathotypes, and provide some examples of outbreaks described in the scientific literature and the measures required to prevent them. Copyright © 2011 Elsevier España, S.L. All rights reserved.

The River Ruhr - an urban river under particular interest for recreational use and as a raw water source for drinking water: The collaborative research project "Safe Ruhr" - microbiological aspects.

PubMed

Strathmann, Martin; Horstkott, Marina; Koch, Christoph; Gayer, Uta; Wingender, Jost

2016-10-01

Along the intense industrialization of the Ruhr valley (Germany), the River Ruhr became increasingly polluted. Over time, using it for recreational purposes became a serious health hazard and bathing was banned due to chemical and microbiological risks. The purpose of the collaborative project "Safe Ruhr" was to verify the current status and to provide a scientific basis for lifting the bathing ban. As the river also provides a raw water source for drinking water production, it was investigated how well the treatment procedures control possible hygienic risks. As study area, the barrier Lake Baldeney was chosen as it embraces earlier bathing sites and tributes to river bank filtration water for drinking water treatment plants. The hygienic condition of the river water was determined over 18 months by measuring general physical, chemical and microbiological water quality parameters including fecal indicators, bacterial obligate and facultative pathogens, parasitic protozoa, enteric viruses and schistosome parasites (Trichobilharzia). Samples were taken at eight locations including sites before and after receiving the discharge of stormwater and treated wastewater, potential future bathing sites and a raw water abstraction point for potable water production. In summary, for all investigated physico-chemical parameters no significant difference between the eight investigated sampling locations on a distinct sampling date were observed. This study focused on hygienically relevant bacteria and parasitic protozoa. Fecal indicators, Escherichia coli, intestinal enterococci and Clostridium perfringens as well as coliform bacteria were detected in 94-100% of the water samples. Enteric pathogens, including Campylobacter spp. and Salmonella enterica, were isolated from 33% and 28% of the samples, respectively, in relatively low concentrations. Among the environmental facultative pathogens, P. aeruginosa was detected at a high frequency of 82% of all samples, but in low numbers, while Aeromonas spp. were found in all water samples in relative high concentrations. The levels of all target organisms were not clearly associated with sources of pollution, with the exception of slightly enhanced numbers of coliform bacteria and E. coli downstream of a sewage discharge point from a wastewater treatment plant. Seasonal variations were observed with higher detection rates of Campylobacter spp. in winter and S. enterica in autumn and winter in contrast to the other bacterial groups, which showed no significant fluctuations throughout the year. Precipitation within two days prior to sampling resulted in a trend of enhanced numbers of coliform bacteria, E. coli, intestinal enterococci and Aeromonas. Sampling and analysis of parasitic protozoa was carried out in accordance to the European bathing water guideline and the ISO 15553 method. Characteristics of the river (flow, vegetation, birds protection zone, bathing of people, sewage etc.) were compared to the number of organisms detected. All in all 184 samples were investigated for Cryptosporidium spp. and Giardia spp. 80% of the samples were positive for Giardia spp. with a mean of 5cysts/100l (0.1-157.9). Highest values were achieved in autumn and winter, lowest values during the assumed bathing season. There seemed to be a trend to lower values in and after a reservoir in the river course, but with no statistical significance. A statistical significance could be shown for higher concentrations after heavy rainfall that led to discharge of combined sewage overflows in the city of Essen. Only 29% of the samples were positive for Cryptosporidium spp. with a single maximum value of 27.7 and all other concentrations below 5 oocysts/100l. On a low level there seemed to be slightly higher findings during summer and bathing season than in autumn and winter. No correlation to heavy rainfall could be found. The findings correspond to earlier results from the River Rhine (Germany). The influence of sewage on the water quality of the Ruhr could be shown from the correlation of Giardia load and activity of combined sewage overflows after heavy rainfall. The rare and low findings of Cryptosporidium spp. lead to the same conclusion, that microbial water quality in the investigation area is rather influenced from sewage water than from diffuse water sources into the River Ruhr. Copyright © 2016 Elsevier GmbH. All rights reserved.

7 CFR 331.1 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... microorganism (including, but not limited to, bacteria, viruses, fungi, rickettsiae, or protozoa), or infectious... material or product of plants, animals, microorganisms (including, but not limited to, bacteria, viruses...

Molecular Epidemiology of Giardia, Blastocystis and Cryptosporidium among Indigenous Children from the Colombian Amazon Basin.

PubMed

Sánchez, Angie; Munoz, Marina; Gómez, Natalia; Tabares, Juan; Segura, Laura; Salazar, Ángela; Restrepo, Cristian; Ruíz, Miguel; Reyes, Patricia; Qian, Yuchen; Xiao, Lihua; López, Myriam C; Ramírez, Juan D

2017-01-01

The incidence and prevalence of intestinal parasites in children is most likely due to lack of natural or acquired resistance and differences in behavior and habits closely related to environmental and socioeconomic determinants. The most important protozoa that parasitize humans are Giardia, Entamoeba, Blastocystis , and Cryptosporidium . These parasites present wide intraspecific genetic diversity and subsequently classified into assemblages and subtypes. The Amazon basin is the largest in the world and is the fifth freshwater reserve on the planet. Contradictorily, people living in these areas (Indigenous populations) have poor quality of life, which favors the infection of diseases of fecal-oral transmission. The aim of this work was to unravel the molecular epidemiology of Giardia, Blastocystis and Cryptosporidium across four communities (Puerto Nariño, San Juan del Soco, Villa Andrea and Nuevo Paraíso). We obtained 284 fecal samples from children under 15 years old that were analyzed by direct microscopy (261 samples) and Real Time PCR (qPCR) (284 samples). The positive samples for these protozoa were further characterized by several molecular markers to depict assemblages and subtypes. We observed a frequency of Giardia infection by microscopy of 23.7% (62 samples) and by qPCR of 64.8% (184 samples); for Blastocystis by microscopy of 35.2% (92 samples) and by qPCR of 88.7% (252 samples) and for Cryptosporidium only 1.9% (5 samples) were positive by microscopy and qPCR 1.8% (5 samples). Regarding the Giardia assemblages, using the glutamate dehydrogenase ( gdh) marker we observed AI, BIII and BIV assemblages and when using triose phosphate isomerase ( tpi ) we observed assemblages AI, AII, BIII and BIV. In contrast, Blastocystis STs detected were 1, 2, 3, 4, and 6. Lastly, the species C. viatorum, C. hominis (with the subtypes IdA19 and IaA12R8) and C. parvum (with the subtype IIcA5G3c) were identified. We observed a high profile of zoonotic transmission regarding the Giardia assemblages and Blastocystis STs/alleles. Also, we highlight the elevated frequency of infection by these two protozoans suggesting an active transmission in the area. Our findings reinforces the need to deploy better epidemiological surveillance systems for enteric pathogens in the area.

Protothecal enteritis as a cause of protein-losing enteropathy in a bull.

PubMed

Osterstock, Jason B; Mansell, Joanne L; Roussel, Allen J

2005-11-01

Prototheca spp are achlorophyllic saprophytic algae found in wastewater, sewage, agricultural waste, and possibly elsewhere in the environment. Infections with these organisms have been reported in cattle, humans, and dogs; affected cattle commonly develop mastitis. A 5-year-old Brahman-cross bull was evaluated because of a history of diarrhea and weight loss. The history and physical examination and clinicopathologic findings were similar to those associated with granulomatous enteritis caused by Mycobacterium avium subsp paratuberculosis (Johne's disease), which is the most common protein-losing enteropathy of cattle. However, diagnostic tests for paratuberculosis yielded negative results. Biopsy specimens from the ileum, jejunum, and ileocecal lymph node were collected for histologic examination and preparation of tissue impression smears; Prototheca-like organisms were identified. Because of the poor prognosis associated with this infection and the lack of safe and economical therapeutic agents for cattle, the owner decided to euthanatize the bull. Infection with Prototheca organisms was confirmed postmortem. As this case illustrates, protothecosis may be a cause of granulomatous enteritis in cattle.

21 CFR 520.1660c - Oxytetracycline hydrochloride tablets/boluses.

Code of Federal Regulations, 2014 CFR

2014-04-01

... enteritis caused by Salmonella typhimurium and Escherichia coli (colibacillosis) and bacterial pneumonia... Escherichia coli (colibacillosis) and bacterial pneumonia (shipping fever complex, pasteurellosis) caused by...

21 CFR 520.1660c - Oxytetracycline hydrochloride tablets/boluses.

Code of Federal Regulations, 2012 CFR

2012-04-01

... enteritis caused by Salmonella typhimurium and Escherichia coli (colibacillosis) and bacterial pneumonia... Escherichia coli (colibacillosis) and bacterial pneumonia (shipping fever complex, pasteurellosis) caused by...

21 CFR 520.1660c - Oxytetracycline hydrochloride tablets/boluses.

Code of Federal Regulations, 2013 CFR

2013-04-01

... enteritis caused by Salmonella typhimurium and Escherichia coli (colibacillosis) and bacterial pneumonia... Escherichia coli (colibacillosis) and bacterial pneumonia (shipping fever complex, pasteurellosis) caused by...

21 CFR 520.1660c - Oxytetracycline hydrochloride tablets/boluses.

Code of Federal Regulations, 2011 CFR

2011-04-01

... enteritis caused by Salmonella typhimurium and Escherichia coli (colibacillosis) and bacterial pneumonia... Escherichia coli (colibacillosis) and bacterial pneumonia (shipping fever complex, pasteurellosis) caused by...

Infection in systemic lupus erythematosus, similarities, and differences with lupus flare

PubMed Central

Jung, Ju-Yang; Suh, Chang-Hee

2017-01-01

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with diverse manifestations, and its pathogenesis is unclear and complicated. Infection and SLE are similar in that they both cause inf lammatory reactions in the immune system; however, one functions to protect the body, whereas the other is activated to damage the body. Infection is known as one of the common trigger factors for SLE; there are a number of reports on infectious agents that provoke autoimmune response. Several viruses, bacteria, and protozoa were revealed to cause immune dysfunction by molecular mimicry, epitope spreading, and bystander activation. In contrast, certain pathogens were revealed to protect from immune dysregulation. Infection can be threatening to patients with SLE who have a compromised immune system, and it is regarded as one of the common causes of mortality in SLE. A clinical distinction between infection and lupus f lare up is required when patients with SLE present fevers. With a close-up assessment of symptoms and physical examination, C-reactive protein and disease activity markers play a major role in differentiating the different disease conditions. Vaccination is necessary because protection against infection is important in patients with SLE. PMID:28490724

The ability of select probiotics to reduce enteric Campylobacter colonization in broiler chickens

USDA-ARS?s Scientific Manuscript database

Campylobacter is the leading cause of foodborne illness worldwide and is often associated with consumption and/or mishandling of contaminated poultry products. Probiotic use in poultry has been an effective strategy in reducing other enteric foodborne pathogens but not consistently for Campylobacter...

Development of a Simple, Peripheral-Blood-Based Lateral-Flow Dipstick Assay for Accurate Detection of Patients with Enteric Fever

PubMed Central

Khan, Iqbal Hassan; Sayeed, M. Abu; Sultana, Nishat; Islam, Kamrul; Amin, Jakia; Faruk, M. Omar; Khan, Umama; Khanam, Farhana; Ryan, Edward T.

2016-01-01

Enteric fever is a systemic infection caused by typhoidal strains of Salmonella enterica and is a significant cause of mortality and morbidity in many parts of the world, especially in resource-limited areas. Unfortunately, currently available diagnostic tests for enteric fever lack sensitivity and/or specificity. No true clinically practical gold standard for diagnosing patients with enteric fever exists. Unfortunately, microbiologic culturing of blood is only 30 to 70% sensitive although 100% specific. Here, we report the development of a lateral-flow immunochromatographic dipstick assay based on the detection of Salmonella enterica serovar Typhi (S. Typhi) lipopolysaccharide (LPS)-specific IgG in lymphocyte culture secretion. We tested the assay using samples from 142 clinically suspected enteric fever patients, 28 healthy individuals residing in a zone where enteric fever is endemic, and 35 patients with other febrile illnesses. In our analysis, the dipstick detected all blood culture-confirmed S. Typhi cases (48/48) and 5 of 6 Salmonella enterica serovar Paratyphi A blood cultured-confirmed cases. The test was negative in all 35 individuals febrile with other illnesses and all 28 healthy controls from the zone of endemicity. The test was positive in 19 of 88 individuals with suspected enteric fever but with negative blood cultures. Thus, the dipstick had a sensitivity of 98% compared to blood culture results and a specificity that ranged from 78 to 100% (95% confidence interval [CI], 70 to 100%), depending on the definition of a true negative. These results suggest that this dipstick assay can be very useful for the detection of enteric fever patients especially in regions of endemicity. PMID:26961857

Spatial relationships among soil biota in a contaminated grassland ecosystem at Aberdeen Proving Ground, Maryland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuperman, R.; Williams, G.; Parmelee, R.

1995-12-31

Spatial relationships among soil nematodes and soil microorganisms were investigated in a grassland ecosystem contaminated with heavy metals in the US Army`s Aberdeen Proving Ground. The study quantified fungal and bacterial biomass, the abundance of soil protozoa, and nematodes. Geostatistical techniques were used to determine spatial distributions of these parameters and to evaluate various cross-correlations. The cross-correlations among soil biota numbers were analyzed using two methods: a cross general relative semi-variogram and an interactive graphical data representation using geostatistically estimated data distributions. Both the visualization technique and the cross general relative semi-variogram and an interactive graphical data representation using geostatisticallymore » estimated data distributions. Both the visualization technique and the cross general relative semi-variogram showed a negative correlation between the abundance of fungivore nematodes and fungal biomass, the abundance of bacterivore nematodes and bacterial biomass, the abundance of omnivore/predator nematodes and numbers of protozoa, and between numbers of protozoa and both fungal and bacterial biomass. The negative cross-correlation between soil biota and metal concentrations showed that soil fungi were particularly sensitive to heavy metal concentrations and can be used for quantitative ecological risk assessment of metal-contaminated soils. This study found that geostatistics are a useful tool for describing and analyzing spatial relationships among components of food webs in the soil community.« less

The Prevalence of Canine Oral Protozoa and Their Association with Periodontal Disease.

PubMed

Patel, Niran; Colyer, Alison; Harris, Steve; Holcombe, Lucy; Andrew, Peter

2017-05-01

Periodontal disease is one of the most important health concerns for companion animals. Research into canine forms of periodontitis has focused on the identification and characterization of the bacterial communities present. However, other microorganisms are known to inhabit the oral cavity and could also influence the disease process. A novel, broad spectrum 18S PCR was developed and used, in conjunction with next-generation sequencing analyses to target the identification of protists. Trichomonas sp. and Entamoeba sp. were identified from 92 samples of canine plaque. The overall prevalence of trichomonads was 56.52% (52/92) and entamoebae was 4.34% (4/92). Next-generation sequencing of pooled healthy, gingivitis, early-stage periodontitis, and severe periodontitis samples revealed the proportion of trichomonad sequences to be 3.51% (health), 2.84% (gingivitis), 6.07% (early periodontitis), and 35.04% (severe periodontitis), respectively, and entamoebae to be 0.01% (health), 0.01% (gingivitis), 0.80% (early-stage periodontitis), and 7.91% (severe periodontitis) respectively. Both genera of protists were statistically associated with plaque from dogs with periodontal disease. These findings provide the first conclusive evidence for the presence of oral protozoa in dog plaque and suggest a possible role for protozoa in the periodontal disease process. © 2016 The Author(s) The Journal of Eukaryotic Microbiology published by Wiley Periodicals, Inc. on behalf of International Society of Protistologists.

Coproscopy and molecular screening for detection of intestinal protozoa.

PubMed

Abu-Madi, Marawan; Boughattas, Sonia; Behnke, Jerzy M; Sharma, Aarti; Ismail, Ahmed

2017-09-06

Intestinal parasitosis is one of several health concerns about immigrants who travel from endemic to non-endemic regions. Reliable rapid sensitive diagnostic tools, for use in non-endemic regions, are urgently required to enable frequent assessment of immigrant workers in jobs where risk of local transmission is a particular concern (e.g. food-handlers). We assessed the burden of intestinal protozoa in newly arrived immigrants and those applying for renewal of work permits in Qatar (n = 735), by both microscopic examination of stool samples and by Real Time PCR methodology. Prevalence was considerably higher using RT-PCR compared with coproscopy (Blastocystis hominis: 65.2 vs 7.6%; Giardia duodenalis: 14.3 vs 2.9%; Entamoeba histolytica: 1.6 vs 1.2%). Dientamoeba fragilis was sought only by RT-PCR (prevalence of 25.4%). Prevalence of G. duodenalis was significantly higher in male subjects, associated with blue collar workers and declined over time. Prevalence of B. hominis varied significantly with region of origin of subjects with highest values recorded among African immigrants. Prevalence of D. fragilis also varied with region of origin of subjects, and was lower in young female subjects and in renewal applicants compared with first-time applicants for work permits. We strongly recommend that, henceforth, intestinal protozoa should be screened by RT-PCR, with a particular focus on frequent assessment of immigrant food-handlers.

Simultaneous detection of the protozoan parasites Toxoplasma, Cryptosporidium and Giardia in food matrices and their persistence on basil leaves.

PubMed

Hohweyer, Jeanne; Cazeaux, Catherine; Travaillé, Emmanuelle; Languet, Emilie; Dumètre, Aurélien; Aubert, Dominique; Terryn, Christine; Dubey, Jitender P; Azas, Nadine; Houssin, Maryline; Loïc, Favennec; Villena, Isabelle; La Carbona, Stéphanie

2016-08-01

Toxoplasma gondii, Cryptosporidium spp. and Giardia intestinalis are emerging pathogen parasites in the food domain. However, without standardized methods for their detection in food matrices, parasitic foodborne outbreaks remain neglected. In this study, a new immunomagnetic separation assay (IMS Toxo) targeting the oocyst's wall of T. gondii was developed using a specific purified monoclonal antibody. Performance of this IMS Toxo coupled to microscopic and qPCR analyses was evaluated in terms of limit of detection (LOD) and recovery rate (RR) on: i) simple matrix (LOD = 5 oocysts; RR between 5 and 56%); ii) raspberries and basil (LOD = 33 oocysts/g; RR between 0.2 and 35%). Finally, to simultaneously extract the three protozoa from these food matrices, T. gondii oocysts were directly concentrated (without IMS Toxo) from the supernatant of the IMS of Cryptosporidium and Giardia (oo)cysts. This strategy associated to qPCR detection led to LOD <1 to 3 (oo)cysts/g and RR between 2 and 35%. This procedure was coupled to RT-qPCR analyses and showed that the three protozoa persisted on the leaves of basil and remained viable following storage at 4 °C for 8 days. These data strengthen the need to consider these protozoa in food safety. Copyright © 2016 Elsevier Ltd. All rights reserved.

Natural Intestinal Protozoa in Rodents (Rodentia: Gerbillinae, Murinae, Cricetinae) in Northwestern Iran.

PubMed

Mohebali, Mehdi; Zarei, Zabiholah; Khanaliha, Khadijeh; Kia, Eshrat Beigom; Motavalli-Haghi, Afsaneh; Davoodi, Jaber; Rezaeian, Tahereh; Tarighi, Fathemeh; Rezaeian, Mostafa

2017-01-01

Majority of parasitic infections in rodents have zoonotic importance. This study aimed to determine the frequency and intensity of intestinal protozoa infections of rodents including Meriones persicus, Mus musculus and, C ricetulus migratorius . This survey was conducted in Meshkin Shahr district in northwestern Iran from Mar. to Dec. of 2014. Intestinal samples of 204 rodents including M. persicus (n=117), M. musculus (n=63) and C. migratorius (n=24) were parasitologically examined. Formalin-ether concentration method was done for all of rodents stool samples and observed with light microscope. All of suspected cases were stained with trichorome staining Method. Cultivation in dichromate potassium 2.5% was carried out for all of coccidian positive samples. Acid fast and aniline blue staining methods were used for detecting of coccidian oocysts and intestinal microsporidial spores, respectively. About 121(59.3%) of the caught rodents were generally infected with intestinal protozoa. Entamoeba muris 14(6.9%), Trichomonas muris 55(27.0%), Chilomastix betencourtti 17 (8.3%), Giardia muris 19(9.3%), Eimeria spp. 46(22.5%) , Isospora spp. 4(2%) and Cryptosporidium spp. 1(0.5%) were found from the collected rodents. Microsporidian spores were identified in 63 (31%) out of the 204 collected rodents using aniline blue staining method. Since some of the infections are zoonotic importance thus, control of rodents can be decreased new cases of the parasitic zoonoses in humans.

Natural Intestinal Protozoa in Rodents (Rodentia: Gerbillinae, Murinae, Cricetinae) in Northwestern Iran

PubMed Central

MOHEBALI, Mehdi; ZAREI, Zabiholah; Khanaliha, Khadijeh; KIA, Eshrat Beigom; MOTAVALLI-HAGHI, Afsaneh; DAVOODI, Jaber; REZAEIAN, Tahereh; TARIGHI, Fathemeh; REZAEIAN, Mostafa

2017-01-01

Background: Majority of parasitic infections in rodents have zoonotic importance. This study aimed to determine the frequency and intensity of intestinal protozoa infections of rodents including Meriones persicus, Mus musculus and, Cricetulus migratorius. Methods: This survey was conducted in Meshkin Shahr district in northwestern Iran from Mar. to Dec. of 2014. Intestinal samples of 204 rodents including M. persicus (n=117), M. musculus (n=63) and C. migratorius (n=24) were parasitologically examined. Formalin-ether concentration method was done for all of rodents stool samples and observed with light microscope. All of suspected cases were stained with trichorome staining Method. Cultivation in dichromate potassium 2.5% was carried out for all of coccidian positive samples. Acid fast and aniline blue staining methods were used for detecting of coccidian oocysts and intestinal microsporidial spores, respectively. Results: About 121(59.3%) of the caught rodents were generally infected with intestinal protozoa. Entamoeba muris 14(6.9%), Trichomonas muris 55(27.0%), Chilomastix betencourtti 17 (8.3%), Giardia muris 19(9.3%), Eimeria spp. 46(22.5%), Isospora spp. 4(2%) and Cryptosporidium spp. 1(0.5%) were found from the collected rodents. Microsporidian spores were identified in 63 (31%) out of the 204 collected rodents using aniline blue staining method. Conclusion: Since some of the infections are zoonotic importance thus, control of rodents can be decreased new cases of the parasitic zoonoses in humans. PMID:28979348

Molecular Detection of the Carriage Rate of Four Intestinal Protozoa with Real-Time Polymerase Chain Reaction: Possible Overdiagnosis of Entamoeba histolytica in Nigeria.

PubMed

Efunshile, Michael A; Ngwu, Bethrand A F; Kurtzhals, Jørgen A L; Sahar, Sumrin; König, Brigitte; Stensvold, Christen R

2015-08-01

Diarrhea remains the second largest killer of children worldwide, and Nigeria ranks number two on the list of global deaths attributable to diarrhea. Meanwhile, prevalence studies on potentially diarrheagenic protozoa in asymptomatic carriers using molecular detection methods remain scarce in sub-Saharan countries. To overcome sensitivity issues related to microscopic detection and identification of cysts in stool concentrates, real-time polymerase chain reaction (PCR) was used to analyze genomic DNAs extracted from stool samples from 199 healthy school children for Entamoeba histolytica, E. dispar, Giardia intestinalis, and Cryptosporidium. Questionnaires were administered for epidemiological data collection. E. histolytica was not detected in any of the samples, whereas Giardia (37.2%), E. dispar (18.6%), and Cryptosporidium (1%) were found. Most of the children sourced their drinking water from community wells (91%), while the majority disposed of feces in the bush (81.9%). Our study is the first to use real-time PCR to evaluate the epidemiology of E. histolytica, Giardia, and Cryptosporidium in Nigeria where previous studies using traditional diagnostic techniques have suggested higher and lower carriage rates of E. histolytica and Giardia, respectively. It is also the first study to accurately identify the prevalence of common potentially diarrheagenic protozoa in asymptomatic carriers in sub-Saharan Africa. © The American Society of Tropical Medicine and Hygiene.

Detection of selected intestinal helminths and protozoa at Hospital Universiti Sains Malaysia using multiplex real-time PCR.

PubMed

Basuni, M; Mohamed, Z; Ahmad, M; Zakaria, N Z; Noordin, R

2012-09-01

Intestinal parasites are the causative agents of a number of important human infections in developing countries. The objective of this study was to determine the prevalence of selected helminths and protozoan infections among patients admitted with gastrointestinal disorders at Hospital Universiti Sains Malaysia, Kelantan, Malaysia using multiplex real-time PCR. In addition microscopic examination was also performed following direct smear, zinc sulphate concentration and Kato-Katz thick smear techniques; and the presence of protozoan parasites was confirmed using trichrome and acid-fast stains. Of the 225 faecal samples analysed, 26.2% were positive for intestinal parasites by the multiplex real-time PCR, while 5.3% were positive by microscopy. As compared to microscopy, the multiplex real-time PCR detected 5.8 and 4.5 times more positives for the selected helminth and protozoan infections respectively. Among the selected helminths detected in this study, hookworm was the most prevalent by real-time PCR, while Ascaris lumbricoides was detected the most by microscopy. Meanwhile, among the selected protozoa detected in this study, Entamoeba histolytica was the most prevalent by real-time PCR, however microscopy detected equal number of cases with E. histolytica and Giardia lamblia. This study showed that real-time PCR can be used to obtain a more accurate prevalence data on intestinal helminths and protozoa.

Developing a quick and inexpensive in vitro (non-animal) bioassay for mascara irritation.

PubMed

Thomason, H; Montagnes, D J S

2014-04-01

Mascara is a mild irritant that causes a range of medical problems. Animal models to predict ocular irritation have, however, been questioned at a number of levels, and there is a continued need to develop in vitro testing methods. We assess changes in an easily quantifiable attribute, ciliated protozoan growth rate, as a sensitive, sublethal measure. Specifically, we test six, randomly chosen, commercial mascara products against a control (as treatments) and reveal through ANOVA (n = 6, α = 0.05) significant differences in the specific growth rate to treatments (for both protozoa). We provide evidence that two easily cultured protozoa (Paramecium caudatum, Blepharisma japonicum) should be considered as models to assess ocular irritancy (and possibly cosmetics in general) and establish the groundwork for such studies to be applied at a more commercial level. We do this by developing a bioassay for mascara toxicity and indicate the low cost (after equipment is purchased, on the order of $100s) and the ease of performing such tests (able to be conducted by undergraduate students), as a consideration for their future commercial application. We first examined dose dependence of responses, revealing that there was a need to conduct preliminary work to determine appropriate levels for sublethal responses. We then show that some products resulted in mortality at high concentrations, others decreased growth rate by >50% (compared with the control), whereas others had no significant effect, compared with the control. We have provided a novel, quick and inexpensive means to assess mascara; the next step is to validate these ciliate bioassays by comparison with animal testing and epidemiological studies, which is beyond the scope of this fundamental 'proof-of-concept' study. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Description of development of rumen ecosystem by PCR assay in milk-fed, weaned and finished lambs in an intensive fattening system.

PubMed

Belanche, A; Balcells, J; de la Fuente, G; Yañez-Ruíz, D R; Fondevila, M; Calleja, L

2010-10-01

This study examined the reticulo-rumen characteristics of the microbial community and its fermentative characteristics in milk-fed, at weaning and finished lambs in a conventional fattening system. Five lambs were assigned to each of three groups: milk-fed lambs slaughtered at 30 days (T30), weaned lambs slaughtered at 45 days (T45) and 'finished lambs' slaughtered at 90 days (T90). At slaughter, rumen size, fermentation parameters (pH, volatile fatty acids and microbial enzyme activity) and protozoal counts were recorded. Quantitative PCR was used to quantify the genes encoding 16S and 18S ribosomal DNA of the rumen bacterial and protozoal populations, respectively, and the sequential colonization of the rumen by cellulolytic (Ruminococcus albus, Ruminococcus flavefaciens) and amylolytic (Prevotella ruminicola, Streptococcus bovis) bacteria, and protozoa (Entodinium sp.). Denaturing gradient gel electrophoresis was used to study the development of rumen microbiota biodiversity. Intake of solid food before weaning caused a significant increase in rumen weight (p < 0.0001) and bacterial DNA (p < 0.05) and volatile fatty acid analysis concentration (p < 0.01), whereas pH declined. In milk-fed lambs, cellulolytic bacteria were evident after 30 days. Thereafter, in the 45-day and 90-day groups, the proportions of R. flavefaciens decreased and R. albus increased. Amylolytic bacteria were present in milk-fed lambs; the proportion of P. ruminicola increased in fattening lambs and S. bovis was the least abundant species. Protozoal concentrations were irregular; milk-fed lambs had a significant number of protozoa species from Entodinium and subfamily Isotrichiidae, but they disappeared at weaning. Lamb rumen were refaunated in some individuals at 90 days (Entodinium and subfamily Diplodiniinae spp.), although individual concentrations were variable. © 2009 Blackwell Verlag GmbH.

Intestinal parasitic infections in Iranian preschool and school children: A systematic review and meta-analysis.

PubMed

Daryani, Ahmad; Hosseini-Teshnizi, Saeed; Hosseini, Seyed-Abdollah; Ahmadpour, Ehsan; Sarvi, Shahabeddin; Amouei, Afsaneh; Mizani, Azadeh; Gholami, Sara; Sharif, Mehdi

2017-05-01

Parasitic infections are a serious public health problem because they cause anemia, growth retardation, aggression, weight loss, and other physical and mental health problems, especially in children. Numerous studies have been performed on intestinal parasitic infections in Iranian preschool and school children. However, no study has gathered and analyzed this information systematically. The aim of this study was to provide summary estimates for the available data on intestinal parasitic infections in Iranian children. We searched 9 English and Persian databases, unpublished data, abstracts of scientific congresses during 1996-2015 using the terms intestinal parasite, Giardia, Cryptosporidium, Enterobiusvermicularis, oxyure, school, children, preschool, and Iran. We conducted meta-analysis using STATA, and for all statistical tests, p-value less than 0.05was considered significant. Among the 68,532 publications searched as a result, 103 were eligible for inclusion in the study. The prevalence rate of intestinal parasitic infections was 38% (95% CI- 33%, 43%). Prevalence of protozoa, helminthic intestinal infections, and non-pathogenic parasites was 16.9%, 9.48%, and 18.5%, respectively, which affected 14.27% males and 15.3% females. The rate of infection in preschool and school children was 38.19% and 43.37% respectively. Giardia, Enterobiusvermicularis and Entamoeba coli were the most common among protozoa, helminthic, and non-pathogenic infections (15.1%, 16.5%, and 7.1%, respectively). The data analyses indicated that the prevalence of intestinal parasitic infection is decreasing in Iranian preschool and school children. Improvement of sanitation, personal hygiene, increased awareness of people, seasonal variations, and health education can be effective in reducing parasitic infections in different communities. Copyright © 2017. Published by Elsevier B.V.

Protozoan Predation of Escherichia coli O157:H7 Is Unaffected by the Carriage of Shiga Toxin-Encoding Bacteriophages.

PubMed

Schmidt, Carrie E; Shringi, Smriti; Besser, Thomas E

2016-01-01

Escherichia coli O157:H7 is a food-borne bacterium that causes hemorrhagic diarrhea and hemolytic uremic syndrome in humans. While cattle are a known source of E. coli O157:H7 exposure resulting in human infection, environmental reservoirs may also be important sources of infection for both cattle and humans. Bacteriophage-encoded Shiga toxins (Stx) carried by E. coli O157:H7 may provide a selective advantage for survival of these bacteria in the environment, possibly through their toxic effects on grazing protozoa. To determine Stx effects on protozoan grazing, we co-cultured Paramecium caudatum, a common ciliate protozoon in cattle water sources, with multiple strains of Shiga-toxigenic E. coli O157:H7 and non-Shiga toxigenic cattle commensal E. coli. Over three days at ambient laboratory temperature, P. caudatum consistently reduced both E. coli O157:H7 and non-Shiga toxigenic E. coli populations by 1-3 log cfu. Furthermore, a wild-type strain of Shiga-toxigenic E. coli O157:H7 (EDL933) and isogenic mutants lacking the A subunit of Stx 2a, the entire Stx 2a-encoding bacteriophage, and/or the entire Stx 1-encoding bacteriophage were grazed with similar efficacy by both P. caudatum and Tetrahymena pyriformis (another ciliate protozoon). Therefore, our data provided no evidence of a protective effect of either Stx or the products of other bacteriophage genes on protozoan predation of E. coli. Further research is necessary to determine if the grazing activity of naturally-occurring protozoa in cattle water troughs can serve to decrease cattle exposure to E. coli O157:H7 and other Shiga-toxigenic E. coli.

Relationships between free-living protozoa, cultivable Legionella spp., and water quality characteristics in three drinking water supplies in the Caribbean.

PubMed

Valster, Rinske M; Wullings, Bart A; van den Berg, Riemsdijk; van der Kooij, Dick

2011-10-01

The study whose results are presented here aimed at identifying free-living protozoa (FLP) and conditions favoring the growth of these organisms and cultivable Legionella spp. in drinking water supplies in a tropical region. Treated and distributed water (±30°C) of the water supplies of three Caribbean islands were sampled and investigated with molecular techniques, based on the 18S rRNA gene. The protozoan host Hartmannella vermiformis and cultivable Legionella pneumophila were observed in all three supplies. Operational taxonomic units (OTUs) with the highest similarity to the potential or candidate hosts Acanthamoeba spp., Echinamoeba exundans, E. thermarum, and an Neoparamoeba sp. were detected as well. In total, 59 OTUs of FLP were identified. The estimated protozoan richness did not differ significantly between the three supplies. In supply CA-1, the concentration of H. vermiformis correlated with the concentration of Legionella spp. and clones related to Amoebozoa predominated (82%) in the protozoan community. These observations, the low turbidity (<0.2 nephelometric turbidity units [NTU]), and the varying ATP concentrations (1 to 12 ng liter(-1)) suggest that biofilms promoted protozoan growth in this supply. Ciliophora represented 25% of the protozoan OTUs in supply CA-2 with elevated ATP concentrations (maximum, 55 ng liter(-1)) correlating with turbidity (maximum, 62 NTU) caused by corroding iron pipes. Cercozoan types represented 70% of the protozoan clones in supply CA-3 with ATP concentrations of <1 ng liter(-1) and turbidity of <0.5 NTU in most samples of distributed water. The absence of H. vermiformis in most samples from supply CA-3 suggests that growth of this protozoan is limited at ATP concentrations of <1 ng liter(-1).

Parasitic infections on the shore of Lake Victoria (East Africa) detected by Mini-FLOTAC and standard techniques.

PubMed

Barda, Beatrice; Ianniello, Davide; Zepheryne, Henry; Rinaldi, Laura; Cringoli, Giuseppe; Burioni, Roberto; Albonico, Marco

2014-09-01

Helminths and protozoa infections pose a great burden especially in developing countries, due to morbidity caused by both acute and chronic infection. The aim of our survey was to analyze the intestinal parasitic burden in communities from Mwanza region, Tanzania. Subjects (n=251) from four villages on the South of Lake Victoria have been analyzed for intestinal parasites with direct smear (DS), formol-ether concentration method (FECM) and the newly developed Mini-FLOTAC technique; urinary schistosomiasis was also assessed in a subsample (n=151); symptoms were registered and correlation between clinic and infections was calculated by chi-squared test and logistical regression. Out of the subjects screened for intestinal and for urinary parasites, 87% (218/251) were found positive for any infection, 69% (174/251) carried a helminthic and 67% (167/251) a protozoan infection, almost half of them had a double or triple infection. The most common helminths were hookworms, followed by Schistosoma mansoni and Schistosoma haematobium. Among protozoa, the most common was Entamoeba coli followed by Entamoeba histolytica/dispar and Giardia intestinalis. Mini-FLOTAC detected a number of helminth infections (61.7%) higher than FECM (38.6%) and DS (17.9%). Some positive associations with abdominal symptoms were found and previous treatment was negatively correlated with infection. Despite the limited size of the examined population the current study indicates a high prevalence of intestinal parasitic infection in Bukumbi area, Tanzania, and Mini-FLOTAC showed to be a promising diagnostic tool for helminth infections. This high parasitic burden calls for starting a regular deworming programme and other preventive interventions in schools and in the community. Copyright © 2014 Elsevier B.V. All rights reserved.

Toxicity of chlorine to zebrafish embryos

PubMed Central

Kent, Michael L.; Buchner, Cari; Barton, Carrie; Tanguay, Robert L.

2014-01-01

Surface disinfection of fertilized fish eggs is widely used in aquaculture to reduce extraovum pathogens that may be released from brood fish during spawning, and this is routinely used in zebrafish (Danio rerio) research laboratories. Most laboratories use approximately 25 – 50 ppm unbuffered chlorine solution for 5 – 10 min. Treatment of embryos with chlorine has significant germicidal effects for many Gram-negative bacteria, viruses, and trophozoite stages of protozoa, it has reduced efficacy against cyst or spore stages of protozoa and certain Mycobacterium spp. Therefore, we evaluated the toxicity of unbufferred and buffered chlorine solution to embryos exposed at 6 or 24 hours post-fertilization (hpf) to determine if higher concentrations can be used for treating zebrafish embryos. Most of our experiments entailed using an outbred line (5D), with both mortality and malformations as endpoints. We found that 6 hpf embryos consistently were more resistant than 24 hpf embryos to the toxic effects of chlorine. Chlorine is more toxic and germicidal at lower pHs, and chlorine causes elevated pH. Consistent with this, we found that unbufferred chlorine solutions (pH ca 8–9) were less toxic at corresponding concentrations than solutions buffered to pH 7. Based on our findings here, we recommend treating 6 hpf embryos for 10 min and 24 hpf for 5 min with unbuffered chlorine solution at 100 ppm. One trial indicated that AB fish, a popular outbred line, are more susceptible to toxicity than 5Ds. This suggests that variability between zebrafish lines occurs, and researchers should evaluate each line or strain under their particular laboratory conditions for selection of the optimum chlorine treatment procedure. PMID:24429474

Relationships between Free-Living Protozoa, Cultivable Legionella spp., and Water Quality Characteristics in Three Drinking Water Supplies in the Caribbean▿†

PubMed Central

Valster, Rinske M.; Wullings, Bart A.; van den Berg, Riemsdijk; van der Kooij, Dick

2011-01-01

The study whose results are presented here aimed at identifying free-living protozoa (FLP) and conditions favoring the growth of these organisms and cultivable Legionella spp. in drinking water supplies in a tropical region. Treated and distributed water (±30°C) of the water supplies of three Caribbean islands were sampled and investigated with molecular techniques, based on the 18S rRNA gene. The protozoan host Hartmannella vermiformis and cultivable Legionella pneumophila were observed in all three supplies. Operational taxonomic units (OTUs) with the highest similarity to the potential or candidate hosts Acanthamoeba spp., Echinamoeba exundans, E. thermarum, and an Neoparamoeba sp. were detected as well. In total, 59 OTUs of FLP were identified. The estimated protozoan richness did not differ significantly between the three supplies. In supply CA-1, the concentration of H. vermiformis correlated with the concentration of Legionella spp. and clones related to Amoebozoa predominated (82%) in the protozoan community. These observations, the low turbidity (<0.2 nephelometric turbidity units [NTU]), and the varying ATP concentrations (1 to 12 ng liter−1) suggest that biofilms promoted protozoan growth in this supply. Ciliophora represented 25% of the protozoan OTUs in supply CA-2 with elevated ATP concentrations (maximum, 55 ng liter−1) correlating with turbidity (maximum, 62 NTU) caused by corroding iron pipes. Cercozoan types represented 70% of the protozoan clones in supply CA-3 with ATP concentrations of <1 ng liter−1 and turbidity of <0.5 NTU in most samples of distributed water. The absence of H. vermiformis in most samples from supply CA-3 suggests that growth of this protozoan is limited at ATP concentrations of <1 ng liter−1. PMID:21873489

Top-down effects of a lytic bacteriophage and protozoa on bacteria in aqueous and biofilm phases.

PubMed

Zhang, Ji; Ormälä-Odegrip, Anni-Maria; Mappes, Johanna; Laakso, Jouni

2014-12-01

Lytic bacteriophages and protozoan predators are the major causes of bacterial mortality in natural microbial communities, which also makes them potential candidates for biological control of bacterial pathogens. However, little is known about the relative impact of bacteriophages and protozoa on the dynamics of bacterial biomass in aqueous and biofilm phases. Here, we studied the temporal and spatial dynamics of bacterial biomass in a microcosm experiment where opportunistic pathogenic bacteria Serratia marcescens was exposed to particle-feeding ciliates, surface-feeding amoebas, and lytic bacteriophages for 8 weeks, ca. 1300 generations. We found that ciliates were the most efficient enemy type in reducing bacterial biomass in the open water, but least efficient in reducing the biofilm biomass. Biofilm was rather resistant against bacterivores, but amoebae had a significant long-term negative effect on bacterial biomass both in the open-water phase and biofilm. Bacteriophages had only a minor long-term effect on bacterial biomass in open-water and biofilm phases. However, separate short-term experiments with the ancestral bacteriophages and bacteria revealed that bacteriophages crash the bacterial biomass dramatically in the open-water phase within the first 24 h. Thereafter, the bacteria evolve phage-resistance that largely prevents top-down effects. The combination of all three enemy types was most effective in reducing biofilm biomass, whereas in the open-water phase the ciliates dominated the trophic effects. Our results highlight the importance of enemy feeding mode on determining the spatial distribution and abundance of bacterial biomass. Moreover, the enemy type can be crucially important predictor of whether the rapid defense evolution can significantly affect top-down regulation of bacteria.

Oral vaccination of channel catfish against enteric septicemia of catfish using a live attenuated Edwardsiella ictaluri isolate

USDA-ARS?s Scientific Manuscript database

Enteric septicemia of catfish (ESC), caused by Edwardsiella ictaluri, is the most problematic bacterial disease affecting catfish aquaculture in the southeastern United States. Efforts to develop an effective ESC vaccine have had limited industrial success. In commercial settings, ESC vaccines are...

Dietary supplementation of young broiler chickens with Capsicum and turmeric oleoresins increases resistance to necrotic enteritis

USDA-ARS?s Scientific Manuscript database

The Clostridium-related poultry disease, necrotic enteritis (NE), causes substantial economic losses on a global scale. In this study, a mixture of two plant-derived phytonutrients, Capsicum oleoresin and turmeric oleoresin (XT), was evaluated for its effects on local and systemic immune responses ...

In vitro selection of enteric microflora for potential use as a probiotic culture against Campylobacter in poultry.

USDA-ARS?s Scientific Manuscript database

Campylobacter is one of the most commonly reported bacterial causes of human foodborne illness and epidemiological evidence indicates poultry and poultry products as significant sources of human Campylobacter infection. In an effort to reduce colonization of enteric pathogens in poultry, scientists...

Targeting motility properties of bacteria in the development of probiotic cultures against Campylobacter jejuni in broiler chickens

USDA-ARS?s Scientific Manuscript database

Campylobacter is the leading cause of gastroenteritis worldwide. Campylobacter is commonly present in the intestinal tract of poultry and one strategy to reduce enteric colonization is the use of probiotic cultures. This strategy has successfully reduced enteric colonization of Salmonella, but has...

Molecular Characterization of an Avian Astrovirus

PubMed Central

Koci, Matthew D.; Seal, Bruce S.; Schultz-Cherry, Stacey

2000-01-01

Astroviruses are known to cause enteric disease in several animal species, including turkeys. However, only human astroviruses have been well characterized at the nucleotide level. Herein we report the nucleotide sequence, genomic organization, and predicted amino acid sequence of a turkey astrovirus isolated from poults with an emerging enteric disease. PMID:10846102

Apollo Soyuz mission, toxic gas entered cabin during earth landing sequence

NASA Technical Reports Server (NTRS)

1975-01-01

A postflight analysis is presented of the sequence which caused toxic gas to enter the cabin during repressurization for 30 seconds from manual deployment of the drogue parachutes at 18,550 feet to disabling of the reaction control system at 9600 feet. Results and conclusions are discussed.

IMPROVED DETECTION OF HUMAN ENTERIC VIRUSES IN FOODS BY RT-PCR. (R826139)

EPA Science Inventory

Human enteric viruses (including hepatitis A virus (HAV) and Norwalk-like viruses (NLVs)) are now recognized as common causes of foodborne disease. While methods to detect these agents in clinical specimens have improved significantly over the last 10 years, applications to fo...

DETECTING CCL-RELATED, EMERGING WATERBORNE HUMAN VIRUSES AND VIRAL INDICATORS FOR EXPOSURE ASSESSMENT

EPA Science Inventory

Enteric viruses cause waterborne disease outbreaks in the U.S. and worldwide. The primary focus of this task is to develop methods to measure the occurrence of enteric viruses in environmental and drinking waters. Cell culture- and molecular-based methods are being developed fo...

Enteric-coated aspirin versus other antiplatelet drugs in acute non-cardioembolic ischemic stroke: post-marketing study in Japan.

PubMed

Takahashi, Shunichi; Mizuno, Osamu; Sakaguchi, Toshiaki; Yamada, Takashi; Inuyama, Lyo

2014-01-01

Japanese guidelines recommend aspirin 160-300 mg/day, starting within 48 h, for patients with acute cerebral infarction. However, there are few reports evaluated in Japanese patients. Our objective was to examine the safety and efficacy of enteric-coated aspirin, compared with other oral antiplatelet drugs, in Japanese patients with acute ischemic stroke. We performed a prospective, non-randomized, observational and multicenter study between June 2005 and December 2007. Patients with symptomatic acute ischemic stroke, including transient ischemic attack (TIA), who started enteric-coated aspirin or other antiplatelet drugs within 7 days of hospitalization were registered. Outcome measures evaluated within 3 months were incidence of cerebral and non-cerebral hemorrhagic events, recurrence of ischemic stroke or TIA, non-cerebral ischemic events and death from any cause. Overall, 2,548 and 830 patients treated with enteric-coated aspirin (100-300 mg/day) or other antiplatelet drugs, respectively, were registered; approximately 60% were male, mean age was 70 years, 85% had pre-existing cardiovascular disease or other complications. Enteric-coated aspirin of 100 mg was mainly prescribed, and only approximately half of the patients were started on it within 48 h after onset of ischemic stroke. Safety and efficacy population excluded patients without follow-up data were 2,521 in enteric-coated aspirin and 807 in other antiplatelets. Hemorrhagic events occurred in 46 (1.8%) in the enteric-coated aspirin group and in 13 (1.6%) in the other antiplatelet drugs group, there was not significant. Recurrent ischemic stroke or TIA occurred in 39 (1.5%) of the enteric-coated aspirin and in 18 (2.2%) of other antiplatelet drugs, and there were any-cause death in 16 (0.6%) and 8 (1.0%). Incidences were slightly lower in the enteric-coated aspirin group compared with the other antiplatelet drugs group, but not statistically significant. It seems that these results showed the safety and efficacy of the enteric-coated aspirin in acute stroke care in Japanese patients. Incidence of hemorrhagic events was comparable between the enteric-coated aspirin group and the other antiplatelet drugs group.

Microrobotics: Swimmers by design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aranson, Igor S.

2016-03-16

Scientists have created soft microrobots whose body shapes can be controlled by structured light, and which self-propel by means of travelling-wave body deformations similar to those exhibited by swimming protozoa.

Microrobotics: Swimmers by design

NASA Astrophysics Data System (ADS)

Aranson, Igor S.

2016-03-01

Scientists have created soft microrobots whose body shapes can be controlled by structured light, and which self-propel by means of travelling-wave body deformations similar to those exhibited by swimming protozoa.

August Weismann embraces the protozoa.

PubMed

Churchill, Frederick B

2010-01-01

This paper examines the contents and institutional context of August Weismann's long essay on Amphimixis (1891). Therein he presented detailed discussions of his on-going studies of reduction division and parthenogenesis, but more to the point, he included an elaborate examination of Émile Maupas's two major publications in protozoology. To understand the relevance of this part to the other two, the author briefly reviews highpoints in earlier nineteenth century protozoology and concludes that only in the mid-1870s and 1880s did protozoa add an important dimension to heredity theory. Otto Bütschli and then Maupas provided Weismann with a deeper understanding of how conjugation and fertilization were related but not identical processes. This allowed him to integrate the two into a fuller understanding of evolution by natural selection.

Phylogenetic placement of two previously described intranuclear bacteria from the ciliate Paramecium bursaria (Protozoa, Ciliophora): 'Holospora acuminata' and 'Holospora curviuscula'.

PubMed

Rautian, Maria S; Wackerow-Kouzova, Natalia D

2013-05-01

'Holospora acuminata' infects micronuclei of Paramecium bursaria (Protozoa, Ciliophora), whereas 'Holospora curviuscula' infects the macronucleus in other clones of the same host species. Because these micro-organisms have not been cultivated, their description has been based only on some morphological properties and host and nuclear specificities. One16S rRNA gene sequence of 'H. curviuscula' is present in databases. The systematic position of the representative strain of 'H. curviuscula', strain MC-3, was determined in this study. Moreover, for the first time, two strains of 'H. acuminata', KBN10-1 and AC61-10, were investigated. Phylogenetic analysis indicated that all three strains belonged to the genus Holospora, family Holosporaceae, order Rickettsiales within the Alphaproteobacteria.

Bulky Trichomonad Genomes: Encoding a Swiss Army Knife.

PubMed

Barratt, Joel; Gough, Rory; Stark, Damien; Ellis, John

2016-10-01

The trichomonads are a remarkably successful lineage of ancient, predominantly parasitic protozoa. Recent molecular analyses have revealed extensive duplication of certain genetic loci in trichomonads. Consequently, their genomes are exceptionally large compared to other parasitic protozoa. Retention of these large gene expansions across different trichomonad families raises the question: do these duplications afford an advantage? Many duplicated genes are linked to the parasitic lifestyle and some are regulated differently to their paralogues, suggesting they have acquired new functions. It is proposed that these large genomes encode a Swiss army knife of sorts, packed with a multitude of tools for use in many different circumstances. This may have bestowed trichomonads with the extraordinary versatility that has undoubtedly contributed to their success. Copyright © 2016 Elsevier Ltd. All rights reserved.

Endovascular Management of Acute Enteric Bleeding from Pancreas Transplant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Semiz-Oysu, Aslihan; Cwikiel, Wojciech

2007-04-15

Arterioenteric fistula is a rare but serious complication of enteric drained pancreas transplant, which may lead to massive gastrointestinal bleeding. We present 3 patients with failed enteric drained pancreas transplants and massive gastrointestinal bleeding secondary to arterioenteric fistula. One patient was treated by embolization and the 2 others by stent graft placement. Bleeding was successfully controlled in all cases, at follow up of 5 days, 8 months, and 12 months, respectively. One patient died 24 days after embolization, of unknown causes.

Factors associated with nosocomial diarrhea in patients with enteral tube feeding.

PubMed

Trabal, J; Leyes, P; Hervás, S; Herrera, M; de Talló Forga, Ma

2008-01-01

Diarrhea is a frequent complication associated to enteral tube feeding (ETF) and it is a frequent cause of reduction or suspension of this type of nutritional support. Our objective was to evaluate the factors associated with nosocomial diarrhea in patients receiving ETF. The only significant factor associated with the appearance of diarrhea was antibiotic consumption, specially those patients receiving the combination of two or more antibiotics. We did not find any association between factors related to ETF, analytical parameters, nor other medications and diarrhea. Our observational data supports the idea that ETF should not be seen as a primary cause of diarrhea, other possible causes should be considered before reducing or discontinuing ETF administration.

Legionella pneumophila OxyR Is a Redundant Transcriptional Regulator That Contributes to Expression Control of the Two-Component CpxRA System.

PubMed

Tanner, Jennifer R; Patel, Palak G; Hellinga, Jacqueline R; Donald, Lynda J; Jimenez, Celine; LeBlanc, Jason J; Brassinga, Ann Karen C

2017-03-01

Nominally an environmental organism, Legionella pneumophila is an intracellular parasite of protozoa but is also the causative agent of the pneumonia termed Legionnaires' disease, which results from inhalation of aerosolized bacteria by susceptible humans. Coordination of gene expression by a number of identified regulatory factors, including OxyR, assists L. pneumophila in adapting to the stresses of changing environments. L. pneumophila OxyR (OxyR Lp ) is an ortholog of Escherichia coli OxyR; however, OxyR Lp was shown elsewhere to be functionally divergent, such that it acts as a transcription regulator independently of the oxidative stress response. In this study, the use of improved gene deletion methods has enabled us to generate an unmarked in-frame deletion of oxyR in L. pneumophila Lack of OxyR Lp did not affect in vitro growth or intracellular growth in Acanthamoeba castellanii protozoa and U937-derived macrophages. The expression of OxyR Lp does not appear to be regulated by CpxR, even though purified recombinant CpxR bound a DNA sequence similar to that reported for CpxR elsewhere. Surprisingly, a lack of OxyR Lp resulted in elevated activity of the promoters located upstream of icmR and the lpg1441-cpxA operon, and OxyR Lp directly bound to these promoter regions, suggesting that OxyR Lp is a direct repressor. Interestingly, a strain overexpressing OxyR Lp demonstrated reduced intracellular growth in A. castellanii but not in U937-derived macrophages, suggesting that balanced expression control of the two-component CpxRA system is necessary for survival in protozoa. Taken together, this study suggests that OxyR Lp is a functionally redundant transcriptional regulator in L. pneumophila under the conditions evaluated herein. IMPORTANCE Legionella pneumophila is an environmental pathogen, with its transmission to the human host dependent upon its ability to replicate in protozoa and survive within its aquatic niche. Understanding the genetic factors that contribute to L. pneumophila survival within each of these unique environments will be key to limiting future point-source outbreaks of Legionnaires' disease. The transcriptional regulator L. pneumophila OxyR (OxyR Lp ) has been previously identified as a potential regulator of virulence traits warranting further investigation. This study demonstrated that oxyR is nonessential for L. pneumophila survival in vitro and in vivo via mutational analysis. While the mechanisms of how OxyR Lp expression is regulated remain elusive, this study shows that OxyR Lp negatively regulates the expression of the cpxRA two-component system necessary for intracellular survival in protozoa. Copyright © 2017 American Society for Microbiology.

Role of interferon in resistance and immunity to protozoa

NASA Technical Reports Server (NTRS)

Sonnenfeld, G.; Degee, A. L. W.; Mansfield, J. M.; Newsome, A. L.; Arnold, R. R.

1985-01-01

Production of interferon (I) in response to protozoan infection, and the interferon-mediated inhibition of parasite replication were studied in order to determine if these effects may be related to immunologic-mediated resistance of the hosts. Two extracellular parasites-Trypanosoma brucei rhodesiense and Naegleria fowlei were used. Upon infection with the trypanosome, only resistant strains of mice produced I. An early peak of alpha/beta I is followed by appearance of gamma I, which coincided with antibody production and a drop in parasitemia. In case of the amoeba, pretreatment of its suspension with alpha/beta I inhibits its replication in vitro, and appears to protect mice from the infection and the disease. It is proposed that production of interferon, with its regulatory effect on the immune responses, may play a major role in regulating the processes of protozoan-caused diseases.

Comparison of prevalence factors in horses with and without seropositivity to Neospora hughesi and/or Sarcocystis neurona.

PubMed

Pusterla, Nicola; Tamez-Trevino, Eva; White, Alexandria; Vangeem, Joshua; Packham, Andrea; Conrad, Patricia A; Kass, Philip

2014-05-01

Equine protozoal myeloencephalitis is a commonly diagnosed neurological disease of horses in North America and is caused by infection with Sarcocystis neurona or Neospora hughesi. The aim of this study was to compare prevalence factors among horses seropositive or seronegative to N. hughesi and/or S. neurona. A total of 3123 submissions were included in the study, with horses originating from 49 States. Thirty-eight animals from 21 States tested seropositive for N. hughesi only, 840 horses from 40 States were seropositive for S. neurona only, 25 horses from 14 States were seropositive for both protozoa, and 2220 horses from 49 States tested seronegative for both parasites. Significant associations were found between geographical location (State), month of submission, breed and serological status. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Ecologo-hygienic criteria and monitoring indices of oil-contaminated peaty soils].

PubMed

Dubinina, O N; Khusnutdinova, N Yu; Mikhailova, L V; Yakhina, M R

2014-01-01

Intensive oil extraction in Khanty-Mansi Autonomous Okrug is not uncommon accompanied by emergency situations giving rise to the pollution of soil, surface and groundwater and causing an elevation in the population morbidity rate. The purpose of the study is to substantiate the basis for information value of hygienic indices of peat soils with low levels of oil contamination: from background values to exceeding the latters as much as 10-20 times, to apply in the study results in hygienic monitoring and oil regulation. The study was performed in accordance with the current methodological regulations. There was established the expediency of determination in transforming in the soil, composition of the petroleum hydrocarbons not only alkanes but arenes and resin-asphaltene fractions, indices of phytotoxicity, translocation of petroleum products into plants testing of soil extracts on protozoa and invertebrates.

Treatment of Chagas Cardiomyopathy

PubMed Central

Botoni, Fernando A.; Ribeiro, Antonio Luiz P.; Marinho, Carolina Coimbra; Lima, Marcia Maria Oliveira; Nunes, Maria do Carmo Pereira; Rocha, Manoel Otávio C.

2013-01-01

Chagas' disease (ChD), caused by the protozoa Trypanosoma cruzi (T. cruzi), was discovered and described by the Brazilian physician Carlos Chagas in 1909. After a century of original description, trypanosomiasis still brings much misery to humanity and is classified as a neglected tropical disease prevalent in underdeveloped countries, particularly in South America. It is an increasing worldwide problem due to the number of cases in endemic areas and the migration of infected subjects to more developed regions, mainly North America and Europe. Despite its importance, chronic chagas cardiomyopathy (CCC) pathophysiology is yet poorly understood, and independently of its social, clinical, and epidemiological importance, the therapeutic approach of CCC is still transposed from the knowledge acquired from other cardiomyopathies. Therefore, the objective of this review is to describe the treatment of Chagas cardiomyopathy with emphasis on its peculiarities. PMID:24350293

Epigenetic Regulation of Transcription in Trypanosomatid Protozoa.

PubMed

Martínez-Calvillo, Santiago; Romero-Meza, Gabriela; Vizuet-de-Rueda, Juan C; Florencio-Martínez, Luis E; Manning-Cela, Rebeca; Nepomuceno-Mejía, Tomás

2018-02-01

The Trypanosomatid family includes flagellated parasites that cause fatal human diseases. Remarkably, protein-coding genes in these organisms are positioned in long tandem arrays that are transcribed polycistronically. However, the knowledge about regulation of transcription initiation and termination in trypanosomatids is scarce. The importance of epigenetic regulation in these processes has become evident in the last years, as distinctive histone modifications and histone variants have been found in transcription initiation and termination regions. Moreover, multiple chromatin-related proteins have been identified and characterized in trypanosomatids, including histone-modifying enzymes, effector complexes, chromatin-remodelling enzymes and histone chaperones. Notably, base J, a modified thymine residue present in the nuclear DNA of trypanosomatids, has been implicated in transcriptional regulation. Here we review the current knowledge on epigenetic control of transcription by all three RNA polymerases in this group of early-diverged eukaryotes.

Gene ontology of differentially expressed genes in the Necrotic enteritis induced chicken lines

USDA-ARS?s Scientific Manuscript database

Necrotic enteritis caused by Clostridium perfringens has become prevalent in the broiler industry due to the withdrawal of antibiotics in poultry feed. The expression level of intestinal mRNA from two chicken lines (line 6.3: MD-resistant and 7.2: MD-susceptible) was significantly different followi...

Complete genome sequences of slostridium perfringens strain del1 isolated from necrotic enteritis-afflicted chicken farm

USDA-ARS?s Scientific Manuscript database

Background: Clostridium perfringens (CP) is ubiquitous in the nature. It is a normal inhabitant in the intestinal tracts of animals and human. As the primary etiological agent of gas gangrene, necrosis and bacteremia, CP causes food poisoning, necrotic enteritis (NE), and even death. Recent omics ...

Oral vaccination of channel catfish against enteric septicemia of catfish (ESC) using a live attenuated Edwardsiella ictaluri isolate

USDA-ARS?s Scientific Manuscript database

Enteric septicemia of catfish (ESC), caused by Edwardsiella ictaluri, is the most problematic bacterial disease affecting catfish aquaculture in the southeastern United States. Efforts to develop an effective ESC vaccine have had limited industrial success. In commercial settings, ESC vaccines are t...

DEVELOPMENT OF MULTIPLEX RT-PCR FOR THE DETECTION OF REOVIRUS, HEPATITIS A VIRUS, POLIOVIRUS, NORWALK VIRUS AND ROTAVIRUS

EPA Science Inventory

Water sources are often found to be contaminated by enteric viruses. This is a public health concern as food and waterborne outbreaks caused by enteric viruses such as noroviruses, rotaviruses, hepatitis A virus (HAV) and enteroviruses are a common occurrence. All of these viru...

Surveillance Systems for Waterborne Protozoa: Beyond Method 1623

EPA Science Inventory

1. Brief introduction to waterborne Cryptosporidium and Giardia Historical perspective on detecting Cryptosporidium and Giardia Current detection methodologies 2. US EPA’s waterborne protozoan research program Building a “Protoz...

A Note on the Flora and Fauna in the Rumen of Steers Fed a Feedlot Bloat-provoking Ration and the Effect of Penicillin

PubMed Central

Bryant, M. P.; Robinson, I. M.; Lindahl, Ivan L.

1961-01-01

A study was made of the predominant culturable bacteria and ciliate protozoa present in the rumen of two steers that were regularly bloating on a pelleted ratio containing 22% alfalfa meal, 16% soybean oil meal, 61% barley, and 1% common salt. The ruminal microorganisms in the two animals differed as indicated by a high total culture count of bacteria, an almost complete absence of ciliate protozoa, a low pH, and a difference in the proportions of presumptively identified predominant bacterial groups in one animal (steer 26) as compared with the other (steer 32). The first exposure of the animals to procaine penicillin (75 or 150 mg per day on 2 successive days) resulted in an abnormal ruminal flora 31 hr after the first treatment as indicated by drastic drops in total and cellulolytic bacterial counts and a change in the proportions of predominant bacterial groups. The animals refused feed for 32 to 48 hr after the first treatment. After feed consumption resumed, further treatment with 75 mg penicillin on 4 successive days did not appear to greatly alter the flora and did not result in feed refusal in animal 32. In animal 26, amounts of penicillin progressing from 50 to 200 mg per day did not result in feed refusals and observations on rumen ingesta samples during this period indicated a decrease in total bacterial count, a great increase in numbers of ciliate protozoa, a higher pH, and a change in the proportions of predominant bacterial groups so that the ruminal picture was much more similar to that of animal 32 than to its own during the pre-penicillin period. Bloat was not relieved except during the period of feed refusal. The results indicate that the ruminal flora rapidly adapts to penicillin and that bloat of the feedlot type can occur in animals with widely differing numbers and kinds of bacteria and protozoa. Feedlot bloat does not appear to be correlated with the occurrence or numbers of any of the individual predominant groups of bacteria cultured. PMID:13874139

A note on the flora and fauna in the rumen of steers fed a feedlot bloat-provoking ration and the effect of penicillin.

PubMed

BRYANT, M P; ROBINSON, I M; LINDAHL, I L

1961-11-01

A study was made of the predominant culturable bacteria and ciliate protozoa present in the rumen of two steers that were regularly bloating on a pelleted ratio containing 22% alfalfa meal, 16% soybean oil meal, 61% barley, and 1% common salt. The ruminal microorganisms in the two animals differed as indicated by a high total culture count of bacteria, an almost complete absence of ciliate protozoa, a low pH, and a difference in the proportions of presumptively identified predominant bacterial groups in one animal (steer 26) as compared with the other (steer 32). The first exposure of the animals to procaine penicillin (75 or 150 mg per day on 2 successive days) resulted in an abnormal ruminal flora 31 hr after the first treatment as indicated by drastic drops in total and cellulolytic bacterial counts and a change in the proportions of predominant bacterial groups. The animals refused feed for 32 to 48 hr after the first treatment. After feed consumption resumed, further treatment with 75 mg penicillin on 4 successive days did not appear to greatly alter the flora and did not result in feed refusal in animal 32. In animal 26, amounts of penicillin progressing from 50 to 200 mg per day did not result in feed refusals and observations on rumen ingesta samples during this period indicated a decrease in total bacterial count, a great increase in numbers of ciliate protozoa, a higher pH, and a change in the proportions of predominant bacterial groups so that the ruminal picture was much more similar to that of animal 32 than to its own during the pre-penicillin period. Bloat was not relieved except during the period of feed refusal. The results indicate that the ruminal flora rapidly adapts to penicillin and that bloat of the feedlot type can occur in animals with widely differing numbers and kinds of bacteria and protozoa. Feedlot bloat does not appear to be correlated with the occurrence or numbers of any of the individual predominant groups of bacteria cultured.

Investigating unsaturated fat, monensin, or bromoethanesulfonate in continuous cultures retaining ruminal protozoa. I. Fermentation, biohydrogenation, and microbial protein synthesis.

PubMed

Karnati, S K R; Sylvester, J T; Ribeiro, C V D M; Gilligan, L E; Firkins, J L

2009-08-01

Methane is an end product of ruminal fermentation that is energetically wasteful and contributes to global climate change. Bromoethanesulfonate, animal-vegetable fat, and monensin were compared with a control treatment to suppress different functional groups of ruminal prokaryotes in the presence or absence of protozoa to evaluate changes in fermentation, digestibility, and microbial N outflow. Four dual-flow continuous culture fermenter systems were used in 4 periods in a 4 x 4 Latin square design split into 2 subperiods. In subperiod 1, a multistage filter system (50-microm smallest pore size) retained most protozoa. At the start of subperiod 2, conventional filters (300-microm pore size) were substituted to efflux protozoa via filtrate pumps over 3 d; after a further 7 d of adaptation, the fermenters were sampled for 3 d. Treatments were retained during both subperiods. Flow of total N and digestibilities of NDF and OM were 18, 16, and 9% higher, respectively, for the defaunated subperiod but were not different among treatments. Ammonia concentration was 33% higher in the faunated fermenters but was not affected by treatment. Defaunation increased the flow of nonammonia N and bacterial N from the fermenters. Protozoal counts were not different among treatments, but bromoethanesulfonate increased the generation time from 43.2 to 55.6 h. Methanogenesis was unaffected by defaunation but tended to be increased by unsaturated fat. Defaunation did not affect total volatile fatty acid production but decreased the acetate:propionate ratio; monensin increased production of isovalerate and valerate. Biohydrogenation of unsaturated fatty acids was impaired in the defaunated fermenters because effluent flows of oleic, linoleic, and linolenic acids were 60, 77, and 69% higher, and the ratio of vaccenic acid:unsaturated FA ratio was decreased by 34% in the effluent. This ratio was increased in both subperiods with the added fat diet, indicating an accumulation of intermediates of biohydrogenation. However, the flow of 18:2 conjugated linoleic acid was unaffected by defaunation or by treatments other than added fat. The flows of trans-10, trans-11, and total trans-18:1 fatty acids were not affected by monensin or faunation status.

The quality of microorganism on coal bed methane processing with various livestock waste in laboratory scale

NASA Astrophysics Data System (ADS)

Marlina, E. T.; Kurnani, Tb. B. A.; Hidayati, Y. A.; Rahmah, K. N.; Joni, I. M.; Harlia, E.

2018-02-01

Coal-bed Methane (CBM) is a form of natural gas extracted from coal and has been developed as future energy source. Organic materials are required as nutrition source for methanogenic microbes. The addition of cattle waste in the formation of CBM on coal media can be utilized as organic materials as well as methanogenic microbe sources. This research covered study of total amount of anaerobic microbes, methane production, protozoa, fungi and endoparasites. Descriptive approach is conducted for this study. Media used for culturing methanogens is Nutrient Agar in powder form and Lactose Broth with the addition of rumen fluid. The technique for counting microbes is through Total Plate Count in anaerobic Hungate tube, methane was analyzed using Gas Chromatography (GC), while identification of protozoa, fungi and endoparasites based on its morphology is conducted before and after anaerobic fermentation process. Incubation period is 30 days. The results showed that growth of anaerobic microbes from dairy cattle waste i.e. biogas sludge is 3.57×103 CFU/ml and fresh feces is 3.38 × 104 CFU/ml, growth of anaerobic microbes from beef cattle waste i.e. biogas sludge is 7.0 × 105 CFU/ml; fresh feces is 7.5 x 104 CFU/ml; and rumen contents of about 1.33 × 108 CFU/ml. Methane production in dairy cattle waste in sludge and fresh feces amounted to 10.57% and 2.39%, respectively. Methane production in beef cattle waste in sludge accounted for 5.95%; in fresh feces it is about 0.41%; and rumen contents of 4.92%. Decreasing of protozoa during fermentation to 84.27%, dominated by Eimeria sp. Decreasing of fungi to 16%, dominated by A. Niger, A. Flavus, A. Fumigatus and Monilia sitophila. Decreasing of endoparasitic worms to 15%, dominated by Strongylus sp. and Fasciola sp. The growth of anaerobic microbes and methane production indicated that dairy cattle waste and beef cattle waste have potential as source of methanogenic microbes, meanwhile the decreasing amount of protozoa, fungi and endoparasites indicated that CBM formation process can reduce pollutants from microorganism in the environment.

Anti-Hu antibodies activate enteric and sensory neurons

PubMed Central

Li, Qin; Michel, Klaus; Annahazi, Anita; Demir, Ihsan E.; Ceyhan, Güralp O.; Zeller, Florian; Komorowski, Lars; Stöcker, Winfried; Beyak, Michael J.; Grundy, David; Farrugia, Gianrico; De Giorgio, Roberto; Schemann, Michael

2016-01-01

IgG of type 1 anti-neuronal nuclear antibody (ANNA-1, anti-Hu) specificity is a serological marker of paraneoplastic neurological autoimmunity (including enteric/autonomic) usually related to small-cell lung carcinoma. We show here that IgG isolated from such sera and also affinity-purified anti-HuD label enteric neurons and cause an immediate spike discharge in enteric and visceral sensory neurons. Both labelling and activation of enteric neurons was prevented by preincubation with the HuD antigen. Activation of enteric neurons was inhibited by the nicotinic receptor antagonists hexamethonium and dihydro-β-erythroidine and reduced by the P2X antagonist pyridoxal phosphate-6-azo (benzene-2,4-disulfonic acid (PPADS) but not by the 5-HT3 antagonist tropisetron or the N-type Ca-channel blocker ω-Conotoxin GVIA. Ca++ imaging experiments confirmed activation of enteric neurons but not enteric glia. These findings demonstrate a direct excitatory action of ANNA-1, in particular anti-HuD, on visceral sensory and enteric neurons, which involves nicotinic and P2X receptors. The results provide evidence for a novel link between nerve activation and symptom generation in patients with antibody-mediated gut dysfunction. PMID:27905561

Leishmanization revisited: immunization with a naturally attenuated cutaneous Leishmania donovani isolate from Sri Lanka protects against visceral leishmaniasis.

PubMed

McCall, Laura-Isobel; Zhang, Wen-Wei; Ranasinghe, Shanlindra; Matlashewski, Greg

2013-02-27

Leishmaniasis is a neglected tropical disease caused by Leishmania protozoa and associated with three main clinical presentations: cutaneous, mucocutaneous and visceral leishmaniasis. Visceral leishmaniasis is the second most lethal parasitic disease after malaria and there is so far no human vaccine. Leishmania donovani is a causative agent of visceral leishmaniasis in South East Asia and Eastern Africa. However, in Sri Lanka, L. donovani causes mainly cutaneous leishmaniasis, while visceral leishmaniasis is rare. We investigate here the possibility that the cutaneous form of L. donovani can provide immunological protection against the visceral form of the disease, as a potential explanation for why visceral leishmaniasis is rare in Sri Lanka. Subcutaneous immunization with a cutaneous clinical isolate from Sri Lanka was significantly protective against visceral leishmaniasis in BALB/c mice. Protection was associated with a mixed Th1/Th2 response. These results provide a possible rationale for the scarcity of visceral leishmaniasis in Sri Lanka and could guide leishmaniasis vaccine development efforts. Copyright © 2012 Elsevier Ltd. All rights reserved.

Flavonoids and Chagas' Disease: The Story So Far!

PubMed

Nabavi, Seyed Fazel; Sureda, Antoni; Daglia, Maria; Izadi, Morteza; Rastrelli, Luca; Nabavi, Seyed Mohammad

2017-01-01

Chagas disease is one of the major health problems in Central and South America, which is caused by the parasitic protozoa, Trypanosoma cruzi. It is commonly transmitted by members of blood-sucking subfamily Triatominae. Chagas disease is associated with cardiac and gastrointestinal manifestations. Up to now, there are no effective vaccines for treatment of Chagas disease and benznidazole and nifurtimox are the only effective anti-Chagas drugs that cause different adverse and side effects. Therefore, much attention has been paid to natural products as novel therapeutic strategies for Chagas disease and its manifestations. Nowadays, some flavonoids could be considered as effective and safe bioactive natural products with potential anti-Chagas activity. Despite the increasing evidence, there is lack of review papers regarding the beneficial effects of flavonoids against Chagas disease and its manifestations. The aim of this paper is to review the available scientific data on the beneficial effects of flavonoids on Chagas disease and its manifestations published over the past two decades. Moreover, we provide an overview on etiology, transmission, epidemiology, clinical manifestations, and current treatment protocols of Chagas disease.

The Gut Microbiome of the Vector Lutzomyia longipalpis Is Essential for Survival of Leishmania infantum

PubMed Central

Kelly, Patrick H.; Bahr, Sarah M.; Serafim, Tiago D.; Ajami, Nadim J.; Petrosino, Joseph F.; Meneses, Claudio; Kirby, John R.; Valenzuela, Jesus G.; Kamhawi, Shaden

2017-01-01

ABSTRACT The vector-borne disease leishmaniasis, caused by Leishmania species protozoa, is transmitted to humans by phlebotomine sand flies. Development of Leishmania to infective metacyclic promastigotes in the insect gut, a process termed metacyclogenesis, is an essential prerequisite for transmission. Based on the hypothesis that vector gut microbiota influence the development of virulent parasites, we sequenced midgut microbiomes in the sand fly Lutzomyia longipalpis with or without Leishmania infantum infection. Sucrose-fed sand flies contained a highly diverse, stable midgut microbiome. Blood feeding caused a decrease in microbial richness that eventually recovered. However, bacterial richness progressively decreased in L. infantum-infected sand flies. Acetobacteraceae spp. became dominant and numbers of Pseudomonadaceae spp. diminished coordinately as the parasite underwent metacyclogenesis and parasite numbers increased. Importantly, antibiotic-mediated perturbation of the midgut microbiome rendered sand flies unable to support parasite growth and metacyclogenesis. Together, these data suggest that the sand fly midgut microbiome is a critical factor for Leishmania growth and differentiation to its infective state prior to disease transmission. PMID:28096483

A brief review on the immunological scenario and recent developmental status of vaccines against enteric fever.

PubMed

Howlader, Debaki Ranjan; Koley, Hemanta; Maiti, Suhrid; Bhaumik, Ushasi; Mukherjee, Priyadarshini; Dutta, Shanta

2017-11-07

Enteric fever has been one of the leading causes of severe illness and deaths worldwide. S. Typhi and S. Paratyphi A, B and C are important enteric fever-causing organisms globally. This infection causes about 21 million cases among which 222,000 typhoid related deaths occurred in 2015. These estimates do not reflect the ultimate and real status of the disease due to the lack of unified diagnostic and proper reporting system from typhoid endemic and other regions. Current control strategies have become increasingly ineffective due to the emergence of multi-drug resistance among the strains. This situation worsens the disease-burden in developing as well as in developed countries. Moreover the emergence of S. Paratyphi A as a major enteric fever-causing organism in several Asian countries, demands a prophylactic measure at this hour. Other than two licensed vaccines of S. Typhi, there are no exsisting vaccines for S. Paratyphi A. Moreover, travelers returning from endemic regions are becoming more susceptible to have these infections. In this situation, a need for bivalent approach is required where a single immunogen (consisting from each organism) will be effective against the disease. In this review, we have focused on the general information about typhoidal fever, its spread and epidemiology in brief and the present status of typhoidal vaccines and its future. This review highlights existing gaps in the typhoidal salmonellae research with a special emphasis on the status of present typhoidal salmonellae vaccine research. Copyright © 2017 Elsevier Ltd. All rights reserved.

THE KEY VIRAL PLAYERS

EPA Science Inventory

A number of different types of human enteric viruses cause waterborne outbreaks when individuals are exposed to contaminated drinking and recreational waters. Members of the enterovirus group cause numerous diseases, including gastroenteritis, encephalitis, meningitis, myocard...

Chapter 42. Waterborne and Foodborne Parasites

USDA-ARS?s Scientific Manuscript database

This chapter identifies the most prominent parasites in North America that are acquired through contaminated food and water including protozoa (Acanthamoeba, Naegleria, Entamoeba, Giardia, Cryptosporidium, Cystoisospora, Cyclospora, Toxoplasma, and Balantidium), nematodes (Trichinella, Angiostrongyl...

Host cell-induced signaling causes Clostridium perfringens to upregulate production of toxins important for intestinal infections

PubMed Central

Chen, Jianming; Ma, Menglin; Uzal, Francisco A; McClane, Bruce A

2014-01-01

Clostridium perfringens causes enteritis and enterotoxemia in humans and livestock due to prolific toxin production. In broth culture, C. perfringens uses the Agr-like quorum sensing (QS) system to regulate production of toxins important for enteritis/enterotoxemia, including beta toxin (CPB), enterotoxin, and epsilon toxin (ETX). The VirS/VirR two-component regulatory system (TCRS) also controls CPB production in broth cultures. Both the Agr-like QS and VirS/VirR systems are important when C. perfringens senses enterocyte-like Caco-2 cells and responds by upregulating CPB production; however, only the Agr-like QS system is needed for host cell-induced ETX production. These in vitro observations have pathophysiologic relevance since both the VirS/VirR and Agr-like QS signaling systems are required for C. perfringens strain CN3685 to produce CPB in vivo and to cause enteritis or enterotoxemia. Thus, apparently upon sensing its presence in the intestines, C. perfringens utilizes QS and TCRS signaling to produce toxins necessary for intestinal virulence. PMID:24061146

21 CFR 520.1660b - Oxytetracycline hydrochloride capsules.

Code of Federal Regulations, 2013 CFR

2013-04-01

... substance produced by growth of Streptomyces rimosus or the same antibiotic substance produced by any other... used in dogs and cats for the treatment of bacterial pneumonia caused by Brucella bronchiseptica, tonsilitis caused by Streptococcus hemolyticus, bacterial enteritis caused by Escherichia coli, urinary tract...

21 CFR 520.1660b - Oxytetracycline hydrochloride capsules.

Code of Federal Regulations, 2014 CFR

2014-04-01

... substance produced by growth of Streptomyces rimosus or the same antibiotic substance produced by any other... used in dogs and cats for the treatment of bacterial pneumonia caused by Brucella bronchiseptica, tonsilitis caused by Streptococcus hemolyticus, bacterial enteritis caused by Escherichia coli, urinary tract...

21 CFR 520.1660b - Oxytetracycline hydrochloride capsules.

Code of Federal Regulations, 2011 CFR

2011-04-01

... substance produced by growth of Streptomyces rimosus or the same antibiotic substance produced by any other... used in dogs and cats for the treatment of bacterial pneumonia caused by Brucella bronchiseptica, tonsilitis caused by Streptococcus hemolyticus, bacterial enteritis caused by Escherichia coli, urinary tract...

21 CFR 520.1660b - Oxytetracycline hydrochloride capsules.

Code of Federal Regulations, 2012 CFR

2012-04-01

... substance produced by growth of Streptomyces rimosus or the same antibiotic substance produced by any other... used in dogs and cats for the treatment of bacterial pneumonia caused by Brucella bronchiseptica, tonsilitis caused by Streptococcus hemolyticus, bacterial enteritis caused by Escherichia coli, urinary tract...

Surveillance Systems for Waterborne Protozoa Past, Present and Future

EPA Science Inventory

OVERVIEW I. Brief introduction to waterborne Cryptosporidium Historical perspective on detecting Cryptosporidium Current detection methodologies II. US EPA’s waterborne protozoan research program Detecting, typing, and tracking sources of Cryptosporidium contami...

Estuarine Food Webs

EPA Science Inventory

Estuaries provide habitat for abundant plants, animals and micro-organisms, ranging from microscopic plankton (bacteria, yeasts, algae, protozoa) to larger benthic and pelagic organisms (seagrass, clams, crabs, sea trout, pelicans and dolphins). Estuarine biota can be characteri...

Diagnosis and treatment of Neospora caninum--associated dermatitis in a red fox (Vulpes vulpes) with concurrent Toxoplasma gondii infection.

PubMed

Duhey, Jitender P; Whitesell, Leah E; Culp, William E; Daye, Sharon

2014-06-01

A 3-mo-old red fox (Vulpes vulpes) developed generalized crusty plaques on its body during rehabilitation after an automobile accident requiring amputation of one leg. Histologic examination of skin lesion biopsy revealed granulomatous dermatitits with many intralesional protozoal tachyzoites. The protozoa stained positively with antibodies to Neospora caninum but not to Toxoplasma gondii. Treatment with clindamycin hydrochloride (10 mg/kg, twice daily, s.c.) for 1 mo completely resolved lesions, and protozoa were not demonstrable in biopsy of skin after treatment. The fox had agglutinating antibodies to T. gondii (modified agglutination test, titer 1:3200) and N. caninum (Neospora agglutination test, titer 1:25), and viable T. gondii (genotype III) was isolated from the skin biopsy after treatment. This is the first report of clinical neosporosis in a wild canid.

[Prevalence of intestinal parasitosis in Reggio Emilia (Italy) during 2009].

PubMed

Guidetti, Carlotta; Ricci, Lidia; Vecchia, Luigi

2010-09-01

The purpose of this survey is to assess the prevalence of intestinal parasites in Reggio Emilia during 2009. We analyzed 1961 samples from 1503 subjects: a copro-parasitological standard examination was performed in 1416 of the subjects and the scotch-test in the remaining 87. Of the 1503 subjects examined, 111 (7.4%) were positive for one or more parasites. Pathogenic parasites were found in 44 subjects (39.6% of all positive subjects) and non-pathogenic protozoa were found in 67 subjects (60.4% of all positive subjects). The most commonly found species were, of the protozoa, Blastocystis hominis, Dientamoeba fragilis and Giardia intestinalis and, of the helminths, Enterobius vermicularis and Taenia Spp. This epidemiological survey shows the need to pay more attention to immigrants and travellers to endemic areas as potential carriers of major parasitic infections in the community.

STUDY OF THE RADIATION-PROTECTIVE ACTION OF SOME PROTECTIVE MATERIALS ON PROTOZOA (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Graevskii, E.Ya.; Nekrasova, I.V.; Shul'mina, A.I.

1962-01-01

The behavior of thiourea derivatives as protective agents during the irradiation of protozoa were investigated together with heroin which possesses a known ability of reducing the radiation reaction of tissues in aqueous solution. It was attempted to determine the effect of toxicity of the radiolytic products and of the medium itself. Cultures of Paramaecium caudatum were used for determining the ef fect of aminoethylisothiuronium bromide hydrobromide, cysteine amine, cystine amine, and heroin. The H/sub 2/Osub 2/ formed during the radiolysis was determined by titration with KMnO/sub 4/. After exposure of the protozea to 100 kr, a protective action was notedmore » by the aminoethylisothiuronium bromide hydrobromide and cystine amine. The lack of efficiency of the cysteine amine is due to its decomposition by radiolysis. (TTT)« less

Photomovements in Ciliated Protozoa

NASA Astrophysics Data System (ADS)

Kuhlmann, Hans-Werner

Ciliates are unicellular, nonphotosynthetic organisms which show a number of light-induced responses. Orientation with respect to the direction of light, phototaxis, has been demonstrated in some species of ciliates. Most of these species bear conspicuous cell organelles such as subpellicular pigment granules, a colored stigma, a watchglass organelle, or a compound crystalline organelle. Several lines of evidence suggest that these kinds of organelles are prerequisites for phototactic orientation of the cells. Photoreceptor molecules presumedly mediating the photobehavior of two species have been identified. The ecological advantage of light-induced responses in ciliated protozoa is still debated. In some cases the organisms may utilize this behavior either to approach their potential prey, to escape their predators, to escape damaging light, or to meet a mating partner. Several species of ciliates display inverse phototactic behavior at different stages of their life cycle.

Protozoan parasites of four species of wild anurans from a local zoo in Malaysia.

PubMed

Mohammad, K N; Badrul, M M; Mohamad, N; Zainal-Abidin, A H

2013-12-01

The parasitic protozoan fauna in sixty-six anurans comprising of Duttaphrynus melanostictus, Phrynoidis juxtaspera, Hylarana erythraea and Polypedates leucomystax collected from Zoo Negara Malaysia was investigated. The distribution and prevalence rate of parasitic species in the digestive tract and blood were examined. Seven species of intestinal protozoa (Opalina ranarum, Cepedea dimidiata, Nycthetorus cordiformis, Entamoeba ranarum, Iodamoeba butschlii, Endamoeba blattae, and Tritrichomonas sp.) and two species of blood protozoa (Lankesterella sp. and Trypanosoma sp.) were recorded. Opalina ranarum was the most common protozoan found in the rectum and intestine (prevalence rate: 34.8%) infecting all host species, with P. juxtaspera heavily infected with the parasite, whereas Tritrichomonas sp. was the least prevalent intestinal species infecting only D. melanostictus. Both Lankesterella sp. and Trypanosoma sp. were found in the blood of H. erythraea.

Rumen ciliate protozoa of domestic sheep (Ovis aries) and goat (Capra aegagrus hircus) in Kyrgyzstan.

PubMed

Gürelli, Gözde; Canbulat, Savaş; Aldayarov, Nurbek; Dehority, Burk A

2016-03-01

Species composition and concentration of rumen ciliate protozoa were investigated in the rumen contents of 14 domestic sheep and 1 goat living in Bishkek, Kyrgyzstan. This is the first report on rumen ciliates from ruminants living in Kyrgyzstan. In sheep 12 genera, 28 species and 12 morphotypes were detected, whereas in goat 8 genera, 12 species and 4 morphotypes were detected. The density of ciliates in sheep was (28.1 ± 20.0) × 10(4) cells mL(-1) and in goat was 37.0 × 10(4) cells mL(-1). Dasytricha ruminantium, Isotricha prostoma, Entodinium simulans and Ophryoscolex caudatus were major species (100%) in sheep, and for the first time, Diplodinium rangiferi was detected in a domestic goat. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Prevalence of intestinal parasites in shelter and hunting dogs in Catalonia, Northeastern Spain.

PubMed

Ortuño, Anna; Scorza, Valeria; Castellà, Joaquim; Lappin, Mike

2014-03-01

To compare the prevalence of intestinal parasites in shelter and hunting dogs in Catalonia, Northeastern Spain, fresh faecal samples from 81 shelter dogs and 88 hunting dogs were collected and analysed by faecal flotation. The overall prevalence of intestinal parasites was 71.6% in each population. In the shelter dog group, 67.9% of dogs were positive for intestinal protozoa and 9.8% were positive for helminths. In the hunting dog group, 20.4% of dogs were positive for intestinal protozoa and 63.6% were positive for helminths. A subset of Giardia-positive samples was evaluated by PCR; Giardia assemblages C or D were detected. These results suggest that comprehensive parasite control measures should be implemented in both shelter and hunting dogs in Catalonia. Copyright © 2013 Elsevier Ltd. All rights reserved.

Maximizing efficiency of rumen microbial protein production

PubMed Central

Hackmann, Timothy J.; Firkins, Jeffrey L.

2015-01-01

Rumen microbes produce cellular protein inefficiently partly because they do not direct all ATP toward growth. They direct some ATP toward maintenance functions, as long-recognized, but they also direct ATP toward reserve carbohydrate synthesis and energy spilling (futile cycles that dissipate heat). Rumen microbes expend ATP by vacillating between (1) accumulation of reserve carbohydrate after feeding (during carbohydrate excess) and (2) mobilization of that carbohydrate thereafter (during carbohydrate limitation). Protozoa account for most accumulation of reserve carbohydrate, and in competition experiments, protozoa accumulated nearly 35-fold more reserve carbohydrate than bacteria. Some pure cultures of bacteria spill energy, but only recently have mixed rumen communities been recognized as capable of the same. When these communities were dosed glucose in vitro, energy spilling could account for nearly 40% of heat production. We suspect that cycling of glycogen (a major reserve carbohydrate) is a major mechanism of spilling; such cycling has already been observed in single-species cultures of protozoa and bacteria. Interconversions of short-chain fatty acids (SCFA) may also expend ATP and depress efficiency of microbial protein production. These interconversions may involve extensive cycling of intermediates, such as cycling of acetate during butyrate production in certain butyrivibrios. We speculate this cycling may expend ATP directly or indirectly. By further quantifying the impact of reserve carbohydrate accumulation, energy spilling, and SCFA interconversions on growth efficiency, we can improve prediction of microbial protein production and guide efforts to improve efficiency of microbial protein production in the rumen. PMID:26029197