Objective:To develop a quautitative PCR method for detecting hookworm infection and quantification.Methods:A real-time PCR method was designed hased on the intergenic regionⅡof ribosomal DNA of the hookworm Neeator a...Objective:To develop a quautitative PCR method for detecting hookworm infection and quantification.Methods:A real-time PCR method was designed hased on the intergenic regionⅡof ribosomal DNA of the hookworm Neeator americanus.The deteetion limit of this method was compared with the microscopy-hased Kato-Katz method.The real-time PCR method was used to conduct an epidemiological survey of hookworm infection in southern Fujian Province of China.Result:The real-time PCR method was specific for detecting Necator americanus infection,and was more sensitive than conventional PCR or microscopy-based method.A preliminary survey for hookworm infection in villages of Fujian Province confirmed the high prevalence of hnokworm infections in the resident populations.In addition,the infection rate in women was significantly higher than thai of in men.Conclusions:A real-time PCR method is designed,which has increased detection sensitivity for more accurate epidemiological studies of hookworm infections,especially when intensity of the infection needs to he considered.展开更多
Hookworm infection is a relatively common cause of anemia in endemic areas.The most common hookworm species are Ancylostoma duodenale and Necator americanus.In this report we present a case of overt gastrointestinal b...Hookworm infection is a relatively common cause of anemia in endemic areas.The most common hookworm species are Ancylostoma duodenale and Necator americanus.In this report we present a case of overt gastrointestinal bleeding Wause of hookworm infection.Capsule endoscopy revealed many hookworms in the lumen of proximal jejunum where active bleeding was seen. The patient was successfully treated with Albendazole.展开更多
Objective Our objective was to systematically evaluate chemotherapy-based control of ascariasis and hookworm infection and make predictions of the effectiveness of repeated mass treatment at different levels of covera...Objective Our objective was to systematically evaluate chemotherapy-based control of ascariasis and hookworm infection and make predictions of the effectiveness of repeated mass treatment at different levels of coverage in highly endemic areas of China. Methods Field surveys were carried out to acquire the ascariasis and hookworm prevalence and intensity （mean worm burden） at baseline, one month and one year later. We calculated model parameters based on the survey data, then incorporated them into a quantitative framework to predict the prevalence and intensity one year later. Sensitivity analyses were performed to assess the influence of the chemotherapy measures on prevalence and intensity, and model simulations were performed to evaluate the feasibility of achieving the proposed transmission control criteria under different chemotherapy measures. Results The predicted prevalence and intensity one year from baseline were within the 95% confidence interval of actual values. As treatment frequency or coverage increased, the prevalence and intensity decreased. Model simulations show that many rounds of treatment are needed to maintain the prevalence at a low level in highly endemic areas of China. Conclusion We should select different combinations of treatment frequency, coverage and drug efficacy according to available resources and practical attainable conditions. Mathematical modeling could be used to help optimize the chemotherapeutic scheme aiming at specific parasitic species and areas, and to direct the establishment of soil-transmitted helminthiasis control criteria in China.展开更多
Hookworm is an illness caused by an internal sponger called a roundworm.Inferable from deprived cleanliness in the developing nations,hookworm infection is a primary source of concern for both motherly and baby grimne...Hookworm is an illness caused by an internal sponger called a roundworm.Inferable from deprived cleanliness in the developing nations,hookworm infection is a primary source of concern for both motherly and baby grimness.The current framework for hookworm detection is composed of hybrid convolutional neural networks;explicitly an edge extraction framework alongside a hookworm classification framework is developed.To consolidate the cylindrical zones obtained from the edge extraction framework and the trait map acquired into the hookworm scientific categorization framework,pooling layers are proposed.The hookworms display different profiles,widths,and bend directions.These challenges make it difficult for customized hookworm detection.In the proposed method,a contourlet change was used with the development of the Hookworm detection.In this study,standard deviation,skewness,entropy,mean,and vitality were used for separating the highlights of the each form.These estimations were found to be accurate.AdaBoost classifier was utilized to characterize the hookworm pictures.In this paper,the exactness and the territory under bend examination in identifying the hookworm demonstrate its scientific relevance.展开更多
Cutaneous larva migrans (CLM) is a zoonotic hookworm infection of dogs and cats commonly found in low-income countries in the tropical and subtropical regions and travellers to these regions. It is caused by invasion ...Cutaneous larva migrans (CLM) is a zoonotic hookworm infection of dogs and cats commonly found in low-income countries in the tropical and subtropical regions and travellers to these regions. It is caused by invasion of the skin by the parasitic larvae of hookworms which, after entry, move under the skin causing an inflammatory reaction resulting in a single or multiple tracks. Patients commonly present with a progressive, itchy, erythematous serpiginous skin rash, affecting the feet, although it can affect any other parts of the body. The diagnosis is mainly clinical, based on history and physical examination. Treatment of this condition can effectively be achieved with either albendazole or ivermectin. We present a case of a 7-year-old boy who was diagnosed with CLM after presenting to the hospital with a history of a progressive itchy rash with tracks on the left foot. Although CLM is a self-limiting disease, it causes a lot of suffering and, therefore, it is of public concern. There is a need to increase awareness of this disease among health workers, and to implement and promote preventive measures against the disease since the cause is known.展开更多
Objective To determine the length of protection by murine immunization with living third stage hookworm larvae (L 3) as measured by reduction in worm burden and host serologic antibody responses Methods Outbred male (...Objective To determine the length of protection by murine immunization with living third stage hookworm larvae (L 3) as measured by reduction in worm burden and host serologic antibody responses Methods Outbred male (Kunming strain) mice were immunized subcutaneously with 500 L 3 once every 2 weeks for a total of immunization for 3 times, and then challenged orally with 1000 L 3 for 1 to 8 weeks after the final immunization Host protective immunity was determined both by the reduction in worm burden as measured by the number of L 3 recovered from murine lungs 48 hour post challenge, as well as by measurement of circulating antibodies Histopathological responses were also examined Non immunized mice served as negative controls Results The protection by L 3 immunization declined over time One or 2 weeks after the final immunization, worm burdens were reduced 72% and 77 5% after challenge respectively In contrast, only 37% reduction in worm burden was observed when the L 3 challenge was delayed by 4 weeks and protection was almost entirely lost when there was an 8 week delay between the time of final immunization and challenge The reduced level of protection over time partially correlated with diminishing L 3 specific antibody responses Host inflammation in the lungs of immunized mice also diminished Conclusion The protection afforded by living L 3 immunization is maximal for the first two weeks after immunization, but then declines significantly over the ensuing展开更多
Background:Humoral and cellular immune responses play protective roles against Mycobacterium tuberculosis(MTB)infection.However,hookworm infection decreases the immune response to hookworm and bystander antigens.Curre...Background:Humoral and cellular immune responses play protective roles against Mycobacterium tuberculosis(MTB)infection.However,hookworm infection decreases the immune response to hookworm and bystander antigens.Currently,immune responses to co-infection of MTB and hookworm are still unknown,although co-infection has been one of the public health problems in co-endemic areas of pulmonary tuberculosis(PTB)and hookworm disease.Therefore,it is essential to evaluate B and T cell immune responses to the co-infection.Methods:Seventeen PTB cases co-infected with hookworm,26 PTB cases,15 patients with hookworm infection,and 24 healthy controls without PTB or hookworm infection were enrolled in the study.Expressions of CD3,CD4,CD8,CD10,CD19,CD20,CD21,CD25,CD27,CD38,FoxP3,and PD-1 were assessed on B and T cell subsets using multicolor flow cytometry.Results:For the B cell(CD19+)subsets,naïve B cells(CD10−CD27−CD21+CD20+),plasma cells(CD10−CD27+CD21−CD20−),and tissue-like memory B cells(CD10−CD27−CD21−CD20+)had higher proportions,whilst resting memory B cells(CD10−CD27+CD21+CD20+)had lower proportions in the group co-infected with MTB and hookworm as compared to other groups.Frequencies of activated memory B cells(CD10−CD27+CD21−CD20+)did not differ among the four groups.For the T cell(CD3+)subsets,frequencies of regulatory T cells(CD4+CD25+Foxp3+)and exhausted CD4+and CD8+T cells(CD4+PD-1+and CD8+PD-1+)were higher,and frequencies of activated CD4+and CD8+T cells(CD4+CD38+and CD8+CD38+)were lower in the co-infected group as compared to the other groups.Conclusion:The change patterns of the cell profile of circulating lymphocytes were indentified in human co-infection of MTB and hookworm,which might indicate that the humoral and cellular immune responses are more suppressed.展开更多
A quantitative PCR（q PCR） assay was used to quantify Ancylostoma caninum ova in wastewater and sludge samples.We estimated the average gene copy numbers for a single ovum using a mixed population of ova.The average ...A quantitative PCR（q PCR） assay was used to quantify Ancylostoma caninum ova in wastewater and sludge samples.We estimated the average gene copy numbers for a single ovum using a mixed population of ova.The average gene copy numbers derived from the mixed population were used to estimate numbers of hookworm ova in A.caninum seeded and unseeded wastewater and sludge samples.The newly developed qP CR assay estimated an average of3.7 × 10~3 gene copies per ovum,which was then validated by seeding known numbers of hookworm ova into treated wastewater.The qP CR estimated an average of（1.1 ± 0.1）,（8.6 ± 2.9）and（67.3 ± 10.4） ova for treated wastewater that was seeded with（1 ± 0）,（10 ± 2） and（100 ± 21）ova,respectively.The further application of the q PCR assay for the quantification of A.caninum ova was determined by seeding a known numbers of ova into the wastewater matrices.The qP CR results indicated that 50%,90% and 67% of treated wastewater（1 L）,raw wastewater（1 L）and sludge（~4 g） samples had variable numbers of A.caninum gene copies.After conversion of the q PCR estimated gene copy numbers to ova for treated wastewater,raw wastewater,and sludge samples,had an average of 0.02,1.24 and 67 ova,respectively.The result of this study indicated that qP CR can be used for the quantification of hookworm ova from wastewater and sludge samples;however,caution is advised in interpreting qP CR generated data for health risk assessment.展开更多
Objective To explore the possibility of using specific antigens for immunodiagnosis of hookworm desease in endemic area. Method Infective third stage larvae of the canine hookworm, Ancylostoma caninum (A. Cani...Objective To explore the possibility of using specific antigens for immunodiagnosis of hookworm desease in endemic area. Method Infective third stage larvae of the canine hookworm, Ancylostoma caninum (A. Caninum) , were prepared as the source of antigen. Enzyme linked immunoelectrotransfer blotting (EITB) was enployed as an immunodiagnostic method. Results Two immunodominant bands of hookworm antigens (42 kDa and 55 kDa) were recognized by the sera of hookworm infected patients (serum dilution 1∶200; antigen centrifuged at 36 000 r/m for 20 minutes, but not by sera from negative controls. Conclusion The 42 kDa and 55 kDa A. caninum antigens might be the specific antigens that could be used for immunodiagnosis of hookworm disease in endemic area.展开更多
Dear Editor,Hookworm is an important tropical nematode.The worm is a roundworm that can be seen in many tropical areas.Basically,this roundworm can cause gastrointestinal infection and chronic infection and result in ...Dear Editor,Hookworm is an important tropical nematode.The worm is a roundworm that can be seen in many tropical areas.Basically,this roundworm can cause gastrointestinal infection and chronic infection and result in hypochromic microcytic anemia,which is the common public health problem.Focusing on the worm’s life cycle,the hookworm egg will be passed from intestine of infected host and hatched as larva in the soil.Based on this information,bearfooted walking is at risk.In general,hookworm is a geohelminth.展开更多
基金supported by the Fujian Provincial Grants(2008N2005,2009-CXB-67)Xiamen City Science and Technology Grant(3502Z20094021)
文摘Objective:To develop a quautitative PCR method for detecting hookworm infection and quantification.Methods:A real-time PCR method was designed hased on the intergenic regionⅡof ribosomal DNA of the hookworm Neeator americanus.The deteetion limit of this method was compared with the microscopy-hased Kato-Katz method.The real-time PCR method was used to conduct an epidemiological survey of hookworm infection in southern Fujian Province of China.Result:The real-time PCR method was specific for detecting Necator americanus infection,and was more sensitive than conventional PCR or microscopy-based method.A preliminary survey for hookworm infection in villages of Fujian Province confirmed the high prevalence of hnokworm infections in the resident populations.In addition,the infection rate in women was significantly higher than thai of in men.Conclusions:A real-time PCR method is designed,which has increased detection sensitivity for more accurate epidemiological studies of hookworm infections,especially when intensity of the infection needs to he considered.
文摘Hookworm infection is a relatively common cause of anemia in endemic areas.The most common hookworm species are Ancylostoma duodenale and Necator americanus.In this report we present a case of overt gastrointestinal bleeding Wause of hookworm infection.Capsule endoscopy revealed many hookworms in the lumen of proximal jejunum where active bleeding was seen. The patient was successfully treated with Albendazole.
基金supported by the Special Fund for National Health Scientific Research in the Public Interest by the Ministry of Health of China (No.200802023)
文摘Objective Our objective was to systematically evaluate chemotherapy-based control of ascariasis and hookworm infection and make predictions of the effectiveness of repeated mass treatment at different levels of coverage in highly endemic areas of China. Methods Field surveys were carried out to acquire the ascariasis and hookworm prevalence and intensity （mean worm burden） at baseline, one month and one year later. We calculated model parameters based on the survey data, then incorporated them into a quantitative framework to predict the prevalence and intensity one year later. Sensitivity analyses were performed to assess the influence of the chemotherapy measures on prevalence and intensity, and model simulations were performed to evaluate the feasibility of achieving the proposed transmission control criteria under different chemotherapy measures. Results The predicted prevalence and intensity one year from baseline were within the 95% confidence interval of actual values. As treatment frequency or coverage increased, the prevalence and intensity decreased. Model simulations show that many rounds of treatment are needed to maintain the prevalence at a low level in highly endemic areas of China. Conclusion We should select different combinations of treatment frequency, coverage and drug efficacy according to available resources and practical attainable conditions. Mathematical modeling could be used to help optimize the chemotherapeutic scheme aiming at specific parasitic species and areas, and to direct the establishment of soil-transmitted helminthiasis control criteria in China.
基金supported by Korea Institute for Advancement of Technology(KIAT)grant funded by the Korea Government(MOTIE)(P0012724,The Competency Development Program for Industry Specialist)the Soonchunhyang University Research Fund.
文摘Hookworm is an illness caused by an internal sponger called a roundworm.Inferable from deprived cleanliness in the developing nations,hookworm infection is a primary source of concern for both motherly and baby grimness.The current framework for hookworm detection is composed of hybrid convolutional neural networks;explicitly an edge extraction framework alongside a hookworm classification framework is developed.To consolidate the cylindrical zones obtained from the edge extraction framework and the trait map acquired into the hookworm scientific categorization framework,pooling layers are proposed.The hookworms display different profiles,widths,and bend directions.These challenges make it difficult for customized hookworm detection.In the proposed method,a contourlet change was used with the development of the Hookworm detection.In this study,standard deviation,skewness,entropy,mean,and vitality were used for separating the highlights of the each form.These estimations were found to be accurate.AdaBoost classifier was utilized to characterize the hookworm pictures.In this paper,the exactness and the territory under bend examination in identifying the hookworm demonstrate its scientific relevance.
文摘Cutaneous larva migrans (CLM) is a zoonotic hookworm infection of dogs and cats commonly found in low-income countries in the tropical and subtropical regions and travellers to these regions. It is caused by invasion of the skin by the parasitic larvae of hookworms which, after entry, move under the skin causing an inflammatory reaction resulting in a single or multiple tracks. Patients commonly present with a progressive, itchy, erythematous serpiginous skin rash, affecting the feet, although it can affect any other parts of the body. The diagnosis is mainly clinical, based on history and physical examination. Treatment of this condition can effectively be achieved with either albendazole or ivermectin. We present a case of a 7-year-old boy who was diagnosed with CLM after presenting to the hospital with a history of a progressive itchy rash with tracks on the left foot. Although CLM is a self-limiting disease, it causes a lot of suffering and, therefore, it is of public concern. There is a need to increase awareness of this disease among health workers, and to implement and promote preventive measures against the disease since the cause is known.
文摘Objective To determine the length of protection by murine immunization with living third stage hookworm larvae (L 3) as measured by reduction in worm burden and host serologic antibody responses Methods Outbred male (Kunming strain) mice were immunized subcutaneously with 500 L 3 once every 2 weeks for a total of immunization for 3 times, and then challenged orally with 1000 L 3 for 1 to 8 weeks after the final immunization Host protective immunity was determined both by the reduction in worm burden as measured by the number of L 3 recovered from murine lungs 48 hour post challenge, as well as by measurement of circulating antibodies Histopathological responses were also examined Non immunized mice served as negative controls Results The protection by L 3 immunization declined over time One or 2 weeks after the final immunization, worm burdens were reduced 72% and 77 5% after challenge respectively In contrast, only 37% reduction in worm burden was observed when the L 3 challenge was delayed by 4 weeks and protection was almost entirely lost when there was an 8 week delay between the time of final immunization and challenge The reduced level of protection over time partially correlated with diminishing L 3 specific antibody responses Host inflammation in the lungs of immunized mice also diminished Conclusion The protection afforded by living L 3 immunization is maximal for the first two weeks after immunization, but then declines significantly over the ensuing
基金We are grateful to the staff at the Gushi County Center for Disease Control and Prevention,health workers at township hospitals and village clinics in the Gushi County,and to all participants who contributed their blood samples.This project was supported by the National Science&Technology Major Program(grant No.2012ZX10004-220).
文摘Background:Humoral and cellular immune responses play protective roles against Mycobacterium tuberculosis(MTB)infection.However,hookworm infection decreases the immune response to hookworm and bystander antigens.Currently,immune responses to co-infection of MTB and hookworm are still unknown,although co-infection has been one of the public health problems in co-endemic areas of pulmonary tuberculosis(PTB)and hookworm disease.Therefore,it is essential to evaluate B and T cell immune responses to the co-infection.Methods:Seventeen PTB cases co-infected with hookworm,26 PTB cases,15 patients with hookworm infection,and 24 healthy controls without PTB or hookworm infection were enrolled in the study.Expressions of CD3,CD4,CD8,CD10,CD19,CD20,CD21,CD25,CD27,CD38,FoxP3,and PD-1 were assessed on B and T cell subsets using multicolor flow cytometry.Results:For the B cell(CD19+)subsets,naïve B cells(CD10−CD27−CD21+CD20+),plasma cells(CD10−CD27+CD21−CD20−),and tissue-like memory B cells(CD10−CD27−CD21−CD20+)had higher proportions,whilst resting memory B cells(CD10−CD27+CD21+CD20+)had lower proportions in the group co-infected with MTB and hookworm as compared to other groups.Frequencies of activated memory B cells(CD10−CD27+CD21−CD20+)did not differ among the four groups.For the T cell(CD3+)subsets,frequencies of regulatory T cells(CD4+CD25+Foxp3+)and exhausted CD4+and CD8+T cells(CD4+PD-1+and CD8+PD-1+)were higher,and frequencies of activated CD4+and CD8+T cells(CD4+CD38+and CD8+CD38+)were lower in the co-infected group as compared to the other groups.Conclusion:The change patterns of the cell profile of circulating lymphocytes were indentified in human co-infection of MTB and hookworm,which might indicate that the humoral and cellular immune responses are more suppressed.
基金financial support from the Water Corporation(No.XX-09-13910)WA and the Commonwealth Scientific and Industry Research Organisation(CSIRO)(Grant No:EOP 77576),Land and Water Flagship
文摘A quantitative PCR（q PCR） assay was used to quantify Ancylostoma caninum ova in wastewater and sludge samples.We estimated the average gene copy numbers for a single ovum using a mixed population of ova.The average gene copy numbers derived from the mixed population were used to estimate numbers of hookworm ova in A.caninum seeded and unseeded wastewater and sludge samples.The newly developed qP CR assay estimated an average of3.7 × 10~3 gene copies per ovum,which was then validated by seeding known numbers of hookworm ova into treated wastewater.The qP CR estimated an average of（1.1 ± 0.1）,（8.6 ± 2.9）and（67.3 ± 10.4） ova for treated wastewater that was seeded with（1 ± 0）,（10 ± 2） and（100 ± 21）ova,respectively.The further application of the q PCR assay for the quantification of A.caninum ova was determined by seeding a known numbers of ova into the wastewater matrices.The qP CR results indicated that 50%,90% and 67% of treated wastewater（1 L）,raw wastewater（1 L）and sludge（~4 g） samples had variable numbers of A.caninum gene copies.After conversion of the q PCR estimated gene copy numbers to ova for treated wastewater,raw wastewater,and sludge samples,had an average of 0.02,1.24 and 67 ova,respectively.The result of this study indicated that qP CR can be used for the quantification of hookworm ova from wastewater and sludge samples;however,caution is advised in interpreting qP CR generated data for health risk assessment.
文摘Objective To explore the possibility of using specific antigens for immunodiagnosis of hookworm desease in endemic area. Method Infective third stage larvae of the canine hookworm, Ancylostoma caninum (A. Caninum) , were prepared as the source of antigen. Enzyme linked immunoelectrotransfer blotting (EITB) was enployed as an immunodiagnostic method. Results Two immunodominant bands of hookworm antigens (42 kDa and 55 kDa) were recognized by the sera of hookworm infected patients (serum dilution 1∶200; antigen centrifuged at 36 000 r/m for 20 minutes, but not by sera from negative controls. Conclusion The 42 kDa and 55 kDa A. caninum antigens might be the specific antigens that could be used for immunodiagnosis of hookworm disease in endemic area.
文摘Dear Editor,Hookworm is an important tropical nematode.The worm is a roundworm that can be seen in many tropical areas.Basically,this roundworm can cause gastrointestinal infection and chronic infection and result in hypochromic microcytic anemia,which is the common public health problem.Focusing on the worm’s life cycle,the hookworm egg will be passed from intestine of infected host and hatched as larva in the soil.Based on this information,bearfooted walking is at risk.In general,hookworm is a geohelminth.
