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Infection and Immunity Jun 2008Hookworm infection is a major cause of anemia and malnutrition in resource-poor countries. Human and animal studies suggest that infection with these intestinal...
Hookworm infection is a major cause of anemia and malnutrition in resource-poor countries. Human and animal studies suggest that infection with these intestinal nematodes is associated with impaired cellular immunity, characterized by reduced lymphocyte proliferation in response to both parasite and heterologous antigens. We report here data from studies aimed at defining mechanisms through which hookworms modulate the host cellular immune response. Splenocytes and mesenteric lymph node (MLN) cells from hamsters infected with Ancylostoma ceylanicum showed minimal proliferation in response to mitogen at days 20 and 30 postinfection (p.i.), with partial recovery noted at day 70 p.i. The proliferative capacity of enriched splenocyte T-cell preparations from infected animals following stimulation with hookworm antigens was partially restored in the presence of antigen-presenting cells from uninfected hamsters. Analysis by fluorescence-activated cell sorting revealed that hookworm infection is associated with reduced percentages of both CD4(+) and surface immunoglobulin G-positive lymphocytes in the spleen and MLN cells. Splenocytes from infected hamsters also secreted more nitric oxide (NO) in culture than did those from naïve animals. Inhibition of NO secretion was associated with partial restoration of the proliferative capacity of splenocytes from infected animals in response to concanavalin A, suggesting a role for NO in mediating this effect. Together, these data demonstrate that hookworm infection is associated with impaired function of antigen-presenting cells and depletion of important lymphocyte subpopulations and also suggests a role for NO in parasite-induced immunosuppression.
Topics: Ancylostoma; Ancylostomiasis; Animals; B-Lymphocytes; CD4-Positive T-Lymphocytes; Cricetinae; Hemoglobins; Immune Tolerance; Immunoglobulin G; Lymph Nodes; Mesocricetus; Nitric Oxide; Organ Size; Spleen; omega-N-Methylarginine
PubMed: 18347036
DOI: 10.1128/IAI.00094-08 -
BioMed Research International 2018To develop a -shift method for detection of dog-derived and three sets of primers were designed based on three SNPs (ITS71, ITS197, and ITS296) of their internal...
To develop a -shift method for detection of dog-derived and three sets of primers were designed based on three SNPs (ITS71, ITS197, and ITS296) of their internal transcribed spacer 1 (ITS1) sequences. The detection effect of the -shift was assessed through the stability, sensitivity, accuracy test, and clinical detection. The results showed that these three sets of primers could distinguish accurately between and . The coefficient of variation in their values on the three SNPs was 0.09% and 0.15% (ITS71), 0.18% and 0.14% (ITS197), and 0.13% and 0.07% (ITS296), respectively. The lowest detectable concentration of standard plasmids for and was 5.33 × 10 ng/L and 5.03 × 10 ng/L. The -shift results of ten DNA samples from the dog-derived hookworms were consistent with their known species. In the clinical detection of 50 fecal samples from stray dogs, the positive rate of hookworm detected by -shift (42%) was significantly higher than that by microscopic examination (34%), and the former can identify the species. It is concluded that the -shift method is rapid, specific, sensitive, and suitable for the clinical detection and zoonotic risk assessment of the dog-derived hookworm.
Topics: Ancylostoma; Ancylostomiasis; Animals; DNA, Helminth; Dog Diseases; Dogs; Polymorphism, Single Nucleotide
PubMed: 29862291
DOI: 10.1155/2018/7617094 -
International Journal of Infectious... Aug 2017Timely Schistosoma japonicum detection improves outcomes in schistosomiasis. Here, we established a double antibody sandwich ELISA to detect Schistosoma japonicum.
OBJECTIVE
Timely Schistosoma japonicum detection improves outcomes in schistosomiasis. Here, we established a double antibody sandwich ELISA to detect Schistosoma japonicum.
METHODS
Sj29 polyclonal and monoclonal antibodies were developed and identified. A Sj29 double antibody sandwich ELISA was evaluated.
RESULTS
Assay sensitivity for detecting Schistosoma japonicum circulating antigen Sj29 was 76.7% (23/30), 54.5% (18/33) and 50.0% (18/36) in patients with acute, chronic and advanced schistosomiasis. No false positives or cross-reactivity was observed in healthy controls or patients with clonorchiasis, paragonimiasis, or ancylostomiasis, respectively. By contrast, false positives (5.7%) and cross-reactivity (6.5%-10%) were detected using an AWA-ELISA. The circulating antigen positive rates decreased significantly faster than that of the antibody detection after 6 months treatment (22.2%, 4/18 and 88.9%, 16/18). Chi-Square Tests revealed that Sj29 sandwich ELISA had lower sensitivity than AWA indirect ELISA in the detection of S. japonicum infected patients (p<0.05). Although our assay detection specificity in patients infected with other parasites or healthy controls appeared higher, the difference between the assays was insignificant. However, our assay showed significantly better results in monitoring praziquantel therapeutic effects (p=0.001), with antigen-positive rates decreasing significantly faster than antibody detection rates after 6 months of treatment (22.2%, 4/18 versus 88.9%, 16/18).
CONCLUSIONS
Sj29 double antibody sandwich ELISA was established. The specificity of this method for detecting healthy sera was 100%. Meanwhile, Sj29 sandwich ELISA may have a potential diagnostic capability to distinguish current from past infections and assess drug treatment responses.
Topics: Animals; Antibodies, Monoclonal; Antigens, Helminth; Cross Reactions; Enzyme-Linked Immunosorbent Assay; Female; Humans; Mice; Mice, Inbred BALB C; Praziquantel; Rabbits; Schistosoma japonicum; Schistosomiasis japonica; Sensitivity and Specificity
PubMed: 28412409
DOI: 10.1016/j.ijid.2017.04.009 -
Revista Do Instituto de Medicina... 2011
Topics: Ancylostoma; Ancylostomiasis; Animals; Humans; Metaphor; Necator americanus; Necatoriasis
PubMed: 21915471
DOI: 10.1590/s0036-46652011000400013 -
Gastroenterology Research and Practice 2021Ancylostomiasis is a fairly common small bowel parasite disease identified by capsule endoscopy (CE) for which a computer-aided clinical detection method has not been...
Ancylostomiasis is a fairly common small bowel parasite disease identified by capsule endoscopy (CE) for which a computer-aided clinical detection method has not been established. We sought to develop an artificial intelligence system with a convolutional neural network (CNN) to automatically detect hookworms in CE images. We trained a deep CNN system based on a YOLO-V4 (You Look Only Once-Version4) detector using 11236 CE images of hookworms. We assessed its performance by calculating the area under the receiver operating characteristic curve and its sensitivity, specificity, and accuracy using an independent test set of 10,529 small-bowel images including 531 images of hookworms. The trained CNN system required 403 seconds to evaluate 10,529 test images. The area under the curve for the detection of hookworms was 0.972 (95% confidence interval (CI), 0.967-0.978). The sensitivity, specificity, and accuracy of the CNN system were 92.2%, 91.1%, and 91.2%, respectively, at a probability score cut-off of 0.485. We developed and validated a CNN-based system for detecting hookworms in CE images. By combining this high-accuracy, high-speed, and oversight-preventing system with other CNN systems, we hope it will become an important supplement for detecting intestinal abnormalities in CE images. This trial is registered with ChiCTR2000034546 (a clinical research of artificial-intelligence-aided diagnosis for hookworms in small intestine by capsule endoscope images).
PubMed: 34868306
DOI: 10.1155/2021/5682288 -
BMC Infectious Diseases Jun 2011Helminth infection rates in grade three children are used as proxy indicators of community infection status and to guide treatment strategies in endemic areas. However...
BACKGROUND
Helminth infection rates in grade three children are used as proxy indicators of community infection status and to guide treatment strategies in endemic areas. However knowledge, attitudes and practices (KAP) of this target age group (8-10 years) in relation to schistosomiasis, soil transmitted helminthiasis (STHs) and malaria is not known at a time when integrated plasmodium - helminth control strategies are being advocated. This study sought to assess KAP of grade 3 children in relation to schistosomiasis, STHs and malaria in order to establish an effective school based health education for disease transmission control.
METHODS
Grade 3 children (n = 172) attending four randomly selected primary schools (one in rural and 3 in the commercial farming areas) in Zimbabwe were interviewed using a pre-tested interviewer administered questionnaire. The urine filtration technique was used to determine S. haematobium infection status. Infection with S. mansoni and STHs was determined using a combination of results from the Kato Katz and formol ether concentration techniques. P. falciparum was diagnosed by examination of Giemsa stained thick blood smears.
RESULTS
It was observed that 32.0%, 19.2% and 4.1% of the respondents had correct knowledge about the causes of schistosomiasis, malaria and STHs, respectively, whilst 22.1%, 19.2% and 5.8% knew correct measures to control schistosomiasis, malaria and STHs. Sixty-two percent and 44.8% did not use soap to wash hands after toilet and before eating food respectively, whilst 33.1% never wore shoes. There were no functional water points and soap for hand washing after toilet at all schools. There was a high prevalence distribution of all parasites investigated in this study at Msapa primary school - S. haematobium (77.8%), S. mansoni (33.3%) hookworms (29.6%) and P. falciparum (48.1%). Reports that participant had suffered from schistosomiasis and malaria before were significant predictors of these diseases (p = 0.001 and p = 0.042, respectively). Report that participant had blood in urine on the day of examination was a significant predictor of schistosomiasis (p = 0.045).
CONCLUSION
There is a critical need for targeting health messages through schools in order to reach the most susceptible schoolchildren. This will empower the schoolchildren with the basic knowledge and skills ultimately protecting them from acquiring schistosomiasis, STHs and malaria.
Topics: Adolescent; Ancylostoma; Ancylostomiasis; Animals; Chi-Square Distribution; Child; Child, Preschool; Cross-Sectional Studies; Endemic Diseases; Hand Disinfection; Health Knowledge, Attitudes, Practice; Humans; Logistic Models; Malaria, Falciparum; Male; Plasmodium falciparum; Prevalence; Risk Factors; Schistosoma haematobium; Schistosoma mansoni; Schistosomiasis; Schools; Students; Surveys and Questionnaires; Water Supply; Zimbabwe
PubMed: 21668948
DOI: 10.1186/1471-2334-11-169 -
The Journal of Biological Chemistry Feb 2012Bile acid-like molecules named dafachronic acids (DAs) control the dauer formation program in Caenorhabditis elegans through the nuclear receptor DAF-12. This mechanism...
Bile acid-like molecules named dafachronic acids (DAs) control the dauer formation program in Caenorhabditis elegans through the nuclear receptor DAF-12. This mechanism is conserved in parasitic nematodes to regulate their dauer-like infective larval stage, and as such, the DAF-12 ligand binding domain has been identified as an important therapeutic target in human parasitic hookworm species that infect more than 600 million people worldwide. Here, we report two x-ray crystal structures of the hookworm Ancylostoma ceylanicum DAF-12 ligand binding domain in complex with DA and cholestenoic acid (a bile acid-like metabolite), respectively. Structure analysis and functional studies reveal key residues responsible for species-specific ligand responses of DAF-12. Furthermore, DA binds to DAF-12 mechanistically and is structurally similar to bile acids binding to the mammalian bile acid receptor farnesoid X receptor. Activation of DAF-12 by cholestenoic acid and the cholestenoic acid complex structure suggest that bile acid-like signaling pathways have been conserved in nematodes and mammals. Together, these results reveal the molecular mechanism for the interplay between parasite and host, provide a structural framework for DAF-12 as a promising target in treating nematode parasitism, and provide insight into the evolution of gut parasite hormone-signaling pathways.
Topics: Ancylostoma; Ancylostomiasis; Animals; Bile Acids and Salts; Cholestenes; Crystallography, X-Ray; Helminth Proteins; Mammals; Receptors, Cytoplasmic and Nuclear; Structural Homology, Protein
PubMed: 22170062
DOI: 10.1074/jbc.M111.315242 -
Ghana Medical Journal Dec 2016Humans can get infected through direct or indirect contact with infective stages of zoonotic parasites shed to the environment through dog faeces.
BACKGROUND
Humans can get infected through direct or indirect contact with infective stages of zoonotic parasites shed to the environment through dog faeces.
OBJECTIVES
This study was designed to investigate the presence of gastrointestinal parasites present in dog faeces shed on the street of Ibadan metropolis, one of the largest cities in Africa.
METHODS
Twenty-three locations were randomly selected using grid-sampling method. A total of 203 faecal samples collected from the streets of selected areas were processed for detection of helminth eggs and protozoan oocysts using flotation technique. Eggs/oocysts per gram of faeces was counted using modified McMaster technique.
RESULTS
The prevalence of gastrointestinal parasites was 43.3% (88/203). Single and multiple infections were 69 (78.4%) and 19 (21.6%) respectively. The parasites detected were sp. 24.6% (50/88) sp. 14.2% (29/88), sp. 9.8% (20/88), sp. 2.5% (5/88) and sp, 3.9% (8/88). sp. (320 × 10 epg) and sp. (5 × 10 epg) had the highest and least intensity respectively. Streets within residential areas having markets had the highest number of positive samples. All the genera of parasites detected in this study have zoonotic potential.
CONCLUSION
The high prevalence of zoonotic parasites detected in dog faeces from Ibadan metropolis showed that infected stray dogs roam the streets and constitute potential risk to human health. This study suggests the need for enforcement of laws restraining roaming or straying dogs and proper veterinary care of dogs.
FUNDING
None declared.
Topics: Ancylostoma; Ancylostomatoidea; Ancylostomiasis; Animals; Dogs; Feces; Hookworm Infections; Intestinal Diseases, Parasitic; Isospora; Isosporiasis; Nigeria; Parasitic Diseases, Animal; Prevalence; Toxocariasis; Zoonoses
PubMed: 28579625
DOI: 10.4314/gmj.v50i4.2 -
Emerging Infectious Diseases Feb 2017Although hookworm is highly prevalent in the Solomon Islands, the species involved are unknown. We initiated this study in response to finding Ancylostoma ceylanicum...
Although hookworm is highly prevalent in the Solomon Islands, the species involved are unknown. We initiated this study in response to finding Ancylostoma ceylanicum hookworm in a peacekeeper in Australia who had returned from the Solomon Islands. Kato-Katz fecal surveys performed in 2013 and 2014 in 2 village groups in East Malaita, Solomon Islands, identified hookworm-positive samples. These specimens were tested by cytochrome oxidase 1 (cox-1) gene multiplex PCR and sequenced. Of 66 positive specimens, 54 (81.8%) contained only Necator americanus, 11 (16.7%) contained only A. ceylanicum, and 1 (1.5%) contained both species. A. duodenale was not found. Haplotype analysis of cox-1 sequences placed all human isolates (99% bootstrap support) of A. ceylanicum within the zoonotic clade rather than the human-specific clade. This study confirms that A. ceylanicum is endemic in the East Malaita region of this Pacific Island nation. The strain of the A. ceylanicum in this region can be shared among humans, dogs, and cats.
Topics: Adolescent; Adult; Ancylostoma; Ancylostomiasis; Animals; Child; Child, Preschool; Cyclooxygenase 1; Feces; Female; Genes, Helminth; Humans; Male; Melanesia; Parasite Egg Count; Phylogeny; Polymerase Chain Reaction; Population Surveillance; Prevalence; Young Adult
PubMed: 28098526
DOI: 10.3201/eid2302.160822 -
BMJ Case Reports Jan 2021Cutaneous larva migrans is an acquired, self-limited infestation caused by cat hookworm, , and dog hookworm, The disease is acquired by direct contact with contaminated...
Cutaneous larva migrans is an acquired, self-limited infestation caused by cat hookworm, , and dog hookworm, The disease is acquired by direct contact with contaminated soil. Circumrotation is a religious ritual practised by devotees of Hinduism as a fulfilment of vows taken at the shrine and involves rolling over with uncovered upper body on the sand over a distance of up to 600 m. It is a reported mode of acquisition of cutaneous larva migrans infestation. The authors report a 10-year-old boy who acquired cutaneous larva migrans on his right forearm after circumrotation. The forearm is an unusual site for this infestation, and most reported cases had lesions on the feet, thighs and buttocks following either sitting or playing on contaminated soil. The child made complete recovery following treatment with albendazole for 1 week.
Topics: Albendazole; Ancylostomiasis; Anthelmintics; Ceremonial Behavior; Child; Forearm; Hinduism; Humans; Larva Migrans; Male
PubMed: 33495176
DOI: 10.1136/bcr-2020-237204