Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 39
Filter
1.
Disabil Rehabil ; : 1-15, 2023 Oct 19.
Article in English | MEDLINE | ID: mdl-37855247

ABSTRACT

PURPOSE: This review investigated the effectiveness of adjuvant therapy combined with constraint-induced movement therapy (CIMT) in improving the paretic upper limb functionality in adults with stroke sequelae during the subacute to chronic rehabilitation phase. MATERIALS AND METHODS: In this systematic review and meta-analysis of randomized controlled trials (RCT), electronic databases, including PubMed, Web of Science, CINAHL, and MEDLINE, were searched. We included RCTs that investigated the outcomes of adjuvant therapy (i.e. other therapies) added to CIMT compared with CIMT alone. Key trial findings were qualitatively synthesized and analyzed. This meta-analysis examined variables, such as mean scores and standard deviations, using the following outcome measures: Fugl-Meyer Assessment (FMA) upper limb items, Action Research Arm Test (ARAT), Amount of Use (AOU) of Motor Activity Log (MAL), and Quality of Movement (QOM) of MAL. RESULTS: Eighteen eligible RCTs were included in the analysis. Adding CIMT to adjunctive therapy significantly improved FMA compared with CIMT alone (mean difference [MD] 4.02, 95% confidence interval [CI] 2.60-5.44; I2 = 85%; 15 studies; 330 participants). Similarly, the ARAT and MAL-AOU scores improved significantly. CONCLUSIONS: CIMT combined with several adjunctive therapies effectively improved upper limb function.


In recent years, clinical trials combining other therapies with Constraint-induced movement therapy (CIMT) have become increasingly common.This study shows that combining CIMT with adjuvant therapy improves upper limb function.Different protocols of the CIMT in each study could be factor that impacted the results of Motor Activity Log.In clinical practice, the findings of this study into their treatment protocols to improve patient outcomes and ensure the effective application of evidence-based rehabilitation strategies.

2.
Vector Borne Zoonotic Dis ; 22(1): 48-54, 2022 01.
Article in English | MEDLINE | ID: mdl-34981973

ABSTRACT

Schistosoma mekongi infection is endemic in countries along the Mekong River and certain of its tributaries in the lower Mekong basin, especially in Lao People's Democratic Republic and Cambodia. Diagnosis of schistosomiasis is crucial before treatment and epidemiological surveys before and/or after an intervention, such as a mass drug administration. A newly developed immunochromatographic test (ICT) for the diagnosis of schistosomiasis mekongi, based on antiparasite antibody detection in human sera, was evaluated. The schistosomiasis mekongi-ICT (Smk-ICT) strip was developed using somatic antigen from adult S. mekongi. In total, 209 serum samples were examined, including 14 from parasitologically proven schistosomiasis mekongi patients, 30 from schistosomiasis japonica patients, other parasitosis (n = 135), and healthy volunteers (n = 30) from areas not endemic for S. mekongi. Eleven schistosomiasis mekongi samples were positive according to the Smk-ICT, whereas all healthy control samples were negative. Cross-reactions with paragonimiasis heterotremus, sparganosis, trichinellosis, and taeniasis saginata samples were observed at 2.4% (4/165). The diagnostic sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 78.6% (95% confidence interval [CI] 49.2-95.3), 97.6% (95% CI 93.9-99.3), 73.3% (95% CI 44.9-92.2), 98.2% (95% CI 94.7-99.6), and 96.1% (95% CI 92.1-98.4), respectively. The Smk-ICT kit might be useful to assess the prevalence of disease before establishing transmission control and mass deworming campaigns in countries in the Mekong River subregion.


Subject(s)
Schistosomiasis , Animals , Humans , Immunoassay/veterinary , Laos/epidemiology , Prevalence , Schistosoma , Schistosomiasis/diagnosis , Schistosomiasis/epidemiology , Schistosomiasis/veterinary
3.
Int J Infect Dis ; 107: 47-52, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33864916

ABSTRACT

OBJECTIVE: Schistosomiasis japonica is an important helminthic disease in Asia. Sensitive and accurate diagnostic tools are indispensable for clinical diagnosis, screening infection and monitoring its control. In this study, we developed an immunochromatographic test (Sj-ICT) to detect anti-Schistosoma japonicum immunoglobulin G antibodies in human sera. METHODS: Somatic extract from adult S. japonicum was used as an antigen. The Sj-ICT was developed and optimized as a point-of-care test. All 214 human serum samples were evaluated for diagnostic usefulness and comparison with an enzyme-linked immunosorbent assay (ELISA). RESULTS: The diagnostic sensitivity, specificity, positive and negative predictive values, and accuracy of the Sj-ICT were 90.8%, 87.9%, 86.4%, 91.9% and 89.3%, respectively. For ELISA the values were respectively 91.8%, 87.9%, 86.5%, 92.7% and 89.7%. The concordance between both methods was 86.4 % (Cohen's kappa value = 0.729). CONCLUSIONS: The immunochromatographic test kit developed can support clinical diagnosis and large-scale surveys in endemic areas without requiring additional facilities or ancillary supplies.


Subject(s)
Antibodies, Helminth/blood , Enzyme-Linked Immunosorbent Assay/methods , Immunoassay/methods , Immunoglobulin G/blood , Point-of-Care Testing , Schistosomiasis japonica/diagnosis , Animals , Asia , Female , Humans , Male , Predictive Value of Tests , Schistosoma japonicum/immunology , Schistosoma japonicum/isolation & purification , Sensitivity and Specificity
4.
Trop Med Infect Dis ; 4(1)2019 Feb 07.
Article in English | MEDLINE | ID: mdl-30736431

ABSTRACT

The areas endemic for schistosomiasis in the Lao People's Democratic Republic and in Cambodia were first reported 50 and 60 years ago, respectively. However, the causative parasite Schistosoma mekongi was not recognized as a separate species until 1978. The infection is distributed along a limited part of the Mekong River, regulated by the focal distribution of the intermediate snail host Neotricula aperta. Although more sensitive diagnostics imply a higher figure, the current use of stool examinations suggests that only about 1500 people are presently infected. This well-characterized setting should offer an exemplary potential for the elimination of the disease from its endemic areas; yet, the local topography, reservoir animals, and a dearth of safe water sources make transmission control a challenge. Control activities based on mass drug administration resulted in strong advances, and prevalence was reduced to less than 5% according to stool microscopy. Even so, transmission continues unabated, and the true number of infected people could be as much as 10 times higher than reported. On-going control activities are discussed together with plans for the future.

5.
Acta Trop ; 141(Pt B): 178-83, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24836919

ABSTRACT

The current status of schistosomiasis in highly endemic areas is difficult to determine by ovum detection because of the superficially low parasite load after mass drug administration, whereas the parasite transmission rates are still high. Cell-free parasite DNA is fragments of parasite-derived DNA existing in the host's body fluids. We conducted population-based studies to test the presence of cell-free schistosome DNA in endemic areas of Sorsogon Province, the Philippines. Schistosome DNA in the serum and urine of Kato-Katz (KK)-positive subjects was detected by PCR (100% sensitivity). Schistosome DNA was also detected from KK-negative subjects (9/22 serum and 10/41 urine samples). Schistosome DNA was found to be network echogenic pattern (NW)-positive (serum 53.3%, urine 42.9%) or NW-negative (serum 25.5%, urine 20.8%) and enzyme-linked immunosorbent assay (ELISA)-positive (serum 47.1%, urine 40%) or ELISA-negative (serum 33.3%, urine 13.3%). These results indicate that cell-free schistosome DNA is a promising diagnostic marker for active schistosome infection in the case of light infection.


Subject(s)
DNA, Protozoan/blood , Endemic Diseases , Schistosoma japonicum/genetics , Schistosomiasis japonica/diagnosis , Schistosomiasis japonica/epidemiology , Adolescent , Adult , Animals , Cell-Free System , DNA, Protozoan/urine , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Middle Aged , Philippines/epidemiology , Polymerase Chain Reaction , Schistosoma japonicum/isolation & purification , Schistosomiasis japonica/genetics , Sensitivity and Specificity , Young Adult
6.
Am J Trop Med Hyg ; 90(6): 1098-101, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24732464

ABSTRACT

A 35-year-old Japanese man had an intermittent fever and mild headache for eight weeks after he returned to Japan from working in Mozambique. He had taken antimalarial prophylaxis (doxycycline) for 25 weeks, and stopped taking this drug two weeks after his return. Microscopic examination of a peripheral blood smear showed a mixed infection with Plasmodium vivax, P. falciparum, and P. ovale. In addition, a nested polymerase chain reaction and subsequent sequencing detected specific DNA sequences of four species of Plasmodium, including P. malariae. The patient was successfully treated with artemether-lumefantrine and primaquine phosphate. The present case is a rare instance of a mixed infection with four species of Plasmodium. Nonimmune persons in malaria-endemic areas may have a risk of mixed infection. All four species must be identified by using sensitive and specific tests, such as a nested polymerase chain reaction, in addition to conventional morphologic identification.


Subject(s)
Antimalarials/therapeutic use , Malaria/diagnosis , Plasmodium/isolation & purification , Adult , Artemether, Lumefantrine Drug Combination , Artemisinins/therapeutic use , Base Sequence , Coinfection , DNA, Protozoan/chemistry , DNA, Protozoan/genetics , Doxycycline/therapeutic use , Drug Combinations , Ethanolamines/therapeutic use , Fluorenes/therapeutic use , Humans , Japan/epidemiology , Malaria/drug therapy , Malaria/prevention & control , Male , Molecular Sequence Data , Mozambique , Parasitemia , Plasmodium/genetics , Polymerase Chain Reaction , Polymorphism, Single Nucleotide , Primaquine/therapeutic use , Sequence Alignment , Sequence Analysis, DNA , Travel , Treatment Outcome
7.
Soc Sci Med ; 110: 31-40, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24713191

ABSTRACT

In the health sectors of low- and middle-income countries, contingent valuation method (CVM) studies on willingness to pay (WTP) have been used to gather information on demand variation or financial perspectives alongside price setting, such as the introduction of user fees and valuation of quality improvements. However, WTP found in most CVM studies have only explored the preferences that consumers express through their WTP without exploring whether they are actually able to pay for it. Therefore, this study examines the issues pertaining to WTP estimation for health services using the conventional CVM. We conducted 202 household interviews in 2008, in which we asked respondents about three types of public health services in Indonesia and assessed WTP estimated by the conventional CVM as well as in the scenario of "resorting to debt" to recognize their budget constraints. We find that all the demand curves for both WTP scenarios show gaps. Furthermore, the gap for midwife services is negatively affected by household income and is larger for the poor. These results prove that CVM studies on WTP do not always reveal WTP in the latter scenario. Those findings suggest that WTP elicited by the conventional CVM is different to that from the maximum price that prevents respondents from resorting to debt as their WTP. In order to bridge this gap in the body of knowledge on this topic, studies should improve the scenarios that CVM analyses use to explore WTP. Furthermore, because valuing or pricing health services based on the results of CVM studies on WTP alone can exacerbate the inequity of access to these services, information provided by such studies requires careful interpretation when used for this purpose, especially for the poor and vulnerable sections of society.


Subject(s)
Financing, Personal , Rural Health Services/economics , Adult , Female , Humans , Indonesia , Male , Middle Aged , Qualitative Research , Socioeconomic Factors
8.
Can J Microbiol ; 59(7): 485-93, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23826958

ABSTRACT

Malaria continues to be a devastating disease. We investigated the factors that control intraerythrocytic development of the parasite Plasmodium falciparum by using a chemically defined medium (CDM) containing non-esterified fatty acid(s) (NEFA) and phospholipids with specific fatty acid moieties, to identify substances crucial for parasite development. Different NEFAs in the CDM played distinct roles by altering the development of the parasite at various stages, with effects ranging from complete growth to growth arrest at the ring stage. We used genome-wide transcriptome profiling to identify genes that were differentially expressed among the different developmental stages of the parasite, cultured in the presence of various NEFAs. We predicted 26 transcripts that were associated with the suppression of schizogony, of which 5 transcripts, including merozoite surface protein 2, a putative DEAD/DEAH box RNA helicase, serine repeat antigen 3, a putative copper channel, and palmitoyl acyltransferase, were particularly associated with blockage of trophozoite progression from the ring stage. Furthermore, the involvement of copper ions in developmental arrest was detected by copper-ion-chelating methods, implying a critical function of copper homeostasis in the early growth stage of the parasite. These results should help to elucidate the mechanisms behind the development of P. falciparum.


Subject(s)
Erythrocytes/parasitology , Fatty Acids/metabolism , Malaria/parasitology , Plasmodium falciparum/growth & development , Plasmodium falciparum/genetics , Acyltransferases/metabolism , Antigens, Protozoan/metabolism , Copper/metabolism , Gene Expression Profiling , Genome-Wide Association Study , Humans , Merozoites/growth & development , Plasmodium falciparum/metabolism , Protozoan Proteins/metabolism , Transcription, Genetic , Trophozoites/metabolism
9.
J Clin Microbiol ; 51(10): 3435-8, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23884992

ABSTRACT

This case of imported refractory schistosomiasis has highlighted the usefulness of cell-free parasite DNA as a diagnostic marker to assess active schistosome infection. In contrast to the rapid disappearance of ova in urine, parasite DNA remained persistent in several other specimen types even after the fourth treatment with praziquantel. This result was consistent with the presence of morphologically intact ova in bladder biopsy samples and with the corresponding symptoms.


Subject(s)
DNA, Helminth/isolation & purification , Drug Monitoring/methods , Parasitology/methods , Schistosomiasis/diagnosis , Schistosomiasis/parasitology , Animals , Anthelmintics/therapeutic use , Biopsy , DNA, Helminth/genetics , Humans , Male , Praziquantel/therapeutic use , Saliva/parasitology , Schistosoma/isolation & purification , Schistosomiasis/drug therapy , Semen/parasitology , Serum/parasitology , Urinary Bladder/parasitology , Urine/parasitology , Young Adult
10.
Parasitol Int ; 61(2): 260-6, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22079238

ABSTRACT

Although the diplogonadic human tapeworm, Diplogonoporus grandis, has long been considered to be a synonym of the whale tapeworm, Diplogonoporus balaenopterae, the identity of the both species at the complete mitochondrial genomes and nuclear DNA levels has been not sufficiently undertaken to date. In the present study, to clarify the taxonomic relationships between D. balaenopterae and D. grandis at the molecular level, the complete mitochondrial genomes of both species were sequenced and compared. In addition, the genetic variation in the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) and the nuclear internal transcribed spacer-1 (ITS-1) region of the ribosomal RNA gene were examined. The complete mitochondrial genomes of D. balaenopterae and D. grandis consisted of 13,724 bp and 13,725 bp, respectively. These mitochondrial genomes contained 12 protein-coding, 22 transfer RNA and 2 ribosomal RNA genes and two longer non-coding regions. Except for Hymenolepis diminuta, the genomic organization in both species was essentially identical to that in other cestode genomes examined to date. However, differences were observed between Diplogonoporus and Diphyllobothrium species in abbreviated stop codons, sequences and the number of repeat units in the 2nd non-coding regions. The genetic differences observed in the mitochondrial genomes, cox1 and ITS-1 regions of both species were considered typical of intraspecific variation. In conclusion, D. balaenopterae is a taxonomically valid species and D. grandis is a junior synonym of D. balaenopterae based on the zoological nomenclature. Further, molecular-phylogenetic analysis confirmed that D. balaenopterae is more closely related to Diphyllobothrium stemmacephalum, the type-species of the genus Diphyllobothrium, and the taxonomical validity of the genera Diplogonoporus and Diphyllobothrium was also discussed.


Subject(s)
Cestoda/classification , Cestoda/genetics , Cestode Infections/parasitology , Genome, Mitochondrial/genetics , Animals , Base Sequence , DNA, Helminth/chemistry , DNA, Helminth/genetics , DNA, Mitochondrial/chemistry , DNA, Mitochondrial/genetics , Humans , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA
11.
Vaccine ; 29(26): 4308-15, 2011 Jun 10.
Article in English | MEDLINE | ID: mdl-21514344

ABSTRACT

Pfs230, surface protein of gametocyte/gamete of the human malaria parasite, Plasmodium falciparum, is a prime candidate of malaria transmission-blocking vaccine. Plasmodium vivax has an ortholog of Pfs230 (Pvs230), however, there has been no study in any aspects on Pvs230 to date. To investigate whether Pvs230 can be a vivax malaria transmission-blocking vaccine, we performed evolutionary and population genetic analysis of the Pvs230 gene (pvs230: PVX_003905). Our analysis of Pvs230 and its orthologs in eight Plasmodium species revealed two distinctive parts: an interspecies variable part (IVP) containing species-specific oligopeptide repeats at the N-terminus and a 7.5kb interspecies conserved part (ICP) containing 14 cysteine-rich domains. Pvs230 was closely related to its orthologs, Pks230 and Pcys230, in monkey malaria parasites. Analysis of 113 pvs230 sequences obtained from worldwide, showed that nucleotide diversity is remarkably low in the non-repeat 8-kb region of pvs230 (θπ=0.00118) with 77 polymorphic nucleotide sites, 40 of which results in amino acid replacements. A signature of purifying selection but not of balancing selection was seen on pvs230. Functional and/or structural constraints may limit the level of polymorphism in pvs230. The observed limited polymorphism in pvs230 should ground for utilization of Pvs230 as an effective transmission-blocking vaccine.


Subject(s)
Amino Acid Sequence , Antigens, Protozoan/immunology , Conserved Sequence , Malaria Vaccines/immunology , Malaria, Vivax/prevention & control , Malaria, Vivax/transmission , Plasmodium vivax/immunology , Protozoan Proteins/immunology , Animals , Antigens, Protozoan/chemistry , Antigens, Protozoan/genetics , DNA, Protozoan/analysis , Humans , Malaria Vaccines/chemistry , Malaria Vaccines/genetics , Malaria, Vivax/parasitology , Molecular Sequence Data , Phylogeny , Protozoan Proteins/chemistry , Protozoan Proteins/genetics , Sequence Alignment , Sequence Analysis, DNA
12.
Environ Health Prev Med ; 16(3): 171-7, 2011 May.
Article in English | MEDLINE | ID: mdl-21431796

ABSTRACT

OBJECTIVES: This study analyzed the risk of infection with Plasmodium vivax in local residents through a stochastic simulation in which an infected tourist, local resident, or immigrants from an endemic area would visit Himi-shi, Toyama prefecture, which is a formerly endemic area in Japan. METHODS: In Toyama, the habitats of Anopheles sinensis, which can transmit P. vivax, have been examined previously. We constructed a stochastic model of P. vivax transmission that can handle small numbers of infected persons and infected mosquitoes. The seasonal fluctuation in the numbers of captured An. sinensis was taken into account in the model. RESULTS: Ten thousand trial simulations were carried out stochastically with a range of human blood indexes (HBI) of 1-10% for a range of months (June-September). The simulation results for a realistic assumption of a 1% HBI showed that the risk of infection for local residents was low (below 1%) except for the immigrants scenario. CONCLUSIONS: The risk of infection among local residents (second cycle) was estimated to be very low for all situations. Therefore, there is little possibility for P. vivax infection to become established in this area of Japan.


Subject(s)
Anopheles/parasitology , Insect Vectors/parasitology , Malaria, Vivax/epidemiology , Malaria, Vivax/transmission , Models, Biological , Animals , Computer Simulation , Emigrants and Immigrants , Humans , Japan/epidemiology , Malaria, Vivax/parasitology , Plasmodium vivax/physiology , Risk Assessment , Seasons , Stochastic Processes
13.
Article in English | MEDLINE | ID: mdl-21323161

ABSTRACT

Schistosomiasis mekongi is an important public health issue in endemic countries. In this study, we evaluated an indirect immunodiagnostic ELISA method using Schistosoma mekongi soluble egg antigen. Sodium metaperiodate (SMP)-ELISA was utilized in order to remove the glycosylated epitopes responsible for false positive reactions and the results using this method were compared with those using conventional ELISA (conv-ELISA). Forty-two serum samples from schistosomiasis mekongi egg-positive patients and 100 serum samples from schistosomiasis-negative Cambodian subjects were tested using both ELISA methods. The ranges of ELISA values for positive and negative sera were distinct on SMP-ELISA, but the ranges of the two groups of sera overlapped on conv-ELISA. Therefore, diagnostic criteria may be established based on the highest ELISA value on negative sera and the lowest ELISA value on positive sera. In the present study, both the sensitivity and specificity of SMP-ELISA reached 100% using the criteria in which an ELISA value > or = 0.2 was positive.


Subject(s)
Periodic Acid/chemistry , Schistosoma/isolation & purification , Schistosomiasis/diagnosis , Animals , Antigens, Helminth/chemistry , Cambodia/epidemiology , Endemic Diseases , Enzyme-Linked Immunosorbent Assay , Feces/parasitology , Humans , Schistosomiasis/drug therapy , Schistosomiasis/epidemiology , Schistosomiasis/prevention & control , Sensitivity and Specificity , Serologic Tests/methods
14.
J Nutr Sci Vitaminol (Tokyo) ; 56(4): 227-34, 2010.
Article in English | MEDLINE | ID: mdl-20924144

ABSTRACT

This paper describes the health and nutritional status and quality of life (QOL) of suburban villagers in the Solomon Islands 3 y after the 1998-2003 ethnic conflict. Cross-sectional data were obtained from a small community located 50 km east of the capital city (n=206, 87 adults and 119 children). A health survey involving urine analysis, anthropometry, and blood pressure measurements was conducted to assess health and nutritional status and child growth. Simultaneously, 57 non-randomly selected adults participated in the QOL questionnaire survey. Results of anthropometry show that participants had good health and nutritional status (mean BMIs: 22.8 and 21.7 for men and women, respectively) and 73% of boys and 83% of girls were judged `normal body size' based on their BMI values. Urinalysis revealed that 88% of the participants were healthy and indicated that they consumed considerable amounts of purchased food such as rice and tinned meat. These findings suggest that the population's lifestyle had essentially recovered from the ethnic conflict. However, possible consequences of the ethnic conflict on the QOL scores were observed in the environmental domain. This study found a positive association between body fat and QOL. This could be interpreted in terms of the traditionally positive view of large bodies in the South Pacific and as resulting from unstable social conditions prevailing after the ethnic conflict.


Subject(s)
Health Status , Nutritional Status , Quality of Life , Warfare , Adipose Tissue , Adult , Body Mass Index , Body Size , Child , Cross-Sectional Studies , Diet , Ethnicity , Female , Growth , Health Surveys , Humans , Male , Melanesia , Suburban Population , Surveys and Questionnaires , Urinalysis
15.
Int J Food Microbiol ; 143(3): 161-5, 2010 Oct 15.
Article in English | MEDLINE | ID: mdl-20826034

ABSTRACT

Anisakid nematodes are known to cause the zoonotic disease, anisakiasis, through the consumption of raw or undercooked fish. The parasites most frequently associated with the disease in humans are categorized as Anisakis type I, which comprise several species of the genus Anisakis. The larvae show primitive forms and lack the detailed morphological characteristics required for precise species identification. Thus, molecular characterization is necessary for determining the species of Anisakis type I larvae and acquiring important clinical and epidemiological information. In this study, we isolated Anisakis type I larvae from hairtail fish caught off the coasts of Taiwan and Japan. The ribosomal DNA (rDNA) internal transcribed spacer (ITS) region was sequenced, and restriction fragment length polymorphism (RFLP) analyses using HinfI and HhaI was carried out for species identification. Most larvae isolated from hairtail caught in Taiwan were Anisakis typica (84%), while those isolated from hairtail caught in Japan were almost exclusively identified either as Anisakis simplex sensu stricto (65%) or Anisakis pegreffii (33%). This is the first report of A. typica in fish obtained from Taiwan. Our results shed the light on the epidemiology of Anisakis type I larvae, which is a potential cause of human anisakiasis in Taiwan and Japan.


Subject(s)
Anisakiasis/veterinary , Anisakis/isolation & purification , Anisakis/physiology , Fishes/parasitology , Nematode Infections/veterinary , Animals , Anisakiasis/epidemiology , Anisakiasis/parasitology , Anisakis/classification , Japan/epidemiology , Larva/classification , Larva/physiology , Nematode Infections/parasitology , Taiwan/epidemiology
16.
Am J Trop Med Hyg ; 83(3): 542-8, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20810818

ABSTRACT

Polymerase chain reaction (PCR) with the specific primer set amplifying 28S ribosomal DNA (rDNA) of Schistosoma japonicum was able to detect genomic DNA of S. japonicum, but not S. mansoni, at 100 fg. This procedure enabled us to detect the DNA from a single miracidium and a snail infected with one miracidium at just 1 day after infection. We compared these results with those from loop-mediated isothermal amplification (LAMP) targeting 28S rDNA and found similar results. The LAMP could amplify the specific DNA from a group of 100 normal snails mixed with one infected snail A PCR screening of infected snails from endemic regions in Anhui Province revealed schistosomal DNA even in snails found negative by microscopy. PCR and LAMP show promise for monitoring the early infection rate in snails, and they may be useful for predicting the risk of infection in the endemic places.


Subject(s)
Polymerase Chain Reaction/methods , Schistosoma japonicum/isolation & purification , Snails/parasitology , Animals , Base Sequence , DNA Primers , DNA, Ribosomal/genetics , Mice , Mice, Inbred ICR , Schistosoma japonicum/genetics
17.
Curr Biol ; 20(14): 1283-9, 2010 Jul 27.
Article in English | MEDLINE | ID: mdl-20656209

ABSTRACT

Plasmodium falciparum is distributed throughout the tropics and is responsible for an estimated 230 million cases of malaria every year, with a further 1.4 billion people at risk of infection. Little is known about the genetic makeup of P. falciparum populations, despite variation in genetic diversity being a key factor in morbidity, mortality, and the success of malaria control initiatives. Here we analyze a worldwide sample of 519 P. falciparum isolates sequenced for two housekeeping genes (63 single nucleotide polymorphisms from around 5000 nucleotides per isolate). We observe a strong negative correlation between within-population genetic diversity and geographic distance from sub-Saharan Africa (R(2) = 0.95) over Africa, Asia, and Oceania. In contrast, regional variation in transmission intensity seems to have had a negligible impact on the distribution of genetic diversity. The striking geographic patterns of isolation by distance observed in P. falciparum mirror the ones previously documented in humans and point to a joint sub-Saharan African origin between the parasite and its host. Age estimates for the expansion of P. falciparum further support that anatomically modern humans were infected prior to their exit out of Africa and carried the parasite along during their colonization of the world.


Subject(s)
Demography , Emigration and Immigration , Genetic Variation , Genetics, Population , Malaria, Falciparum/transmission , Plasmodium falciparum/genetics , Animals , Base Sequence , Bayes Theorem , DNA Primers/genetics , Geography , Humans , Models, Genetic , Molecular Sequence Data , Plasmodium falciparum/physiology , Polymorphism, Single Nucleotide/genetics , Population Dynamics , Sequence Analysis, DNA
18.
Malar J ; 8: 182, 2009 Aug 01.
Article in English | MEDLINE | ID: mdl-19646275

ABSTRACT

BACKGROUND: Detection of Plasmodium species in mosquitoes is important for designing vector control studies. However, most of the PCR-based detection methods show some potential limitations. The objective of this study was to introduce an effective PCR-based method for detecting Plasmodium vivax and Plasmodium falciparum from the field-caught mosquitoes of Papua New Guinea. METHODS: A method has been developed to concurrently detect mitochondrial cytochrome b (Cyt b) of four human Plasmodium species using PCR (Cytb-PCR). To particularly discriminate P. falciparum from P. vivax, Plasmodium ovale and Plasmodium malariae, a polymerase chain reaction-repeated fragment length polymorphism (PCR-RFLP) has further been developed to use with this method. However, due to limited samples number of P. ovale and P. malariae; this study was mainly confined to P. vivax and P. falciparum. The efficiency of Cytb-PCR was evaluated by comparing it with two 'gold standards' enzyme linked immunosorbent assay specific for circumsporozoite protein (CS-ELISA) using artificially infected mosquitoes; and nested PCR specific for small subunit ribosomal RNA (SSUrRNA) using field caught mosquitoes collected from three areas (Kaboibus, Wingei, and Jawia) of the East Sepic Province of Papua New Guinea. RESULTS: A total of 90 mosquitoes were artificially infected with three strains of Plasmodium: P. vivax-210 (n = 30), P. vivax-247 (n = 30) and P. falciparum (n = 30). These infected mosquitoes along with another 32 unfed mosquitoes were first checked for the presence of Plasmodium infection by CS-ELISA, and later the same samples were compared with the Cytb-PCR. CS-ELISA for P. vivax-210, P. vivax-247 and P. falciparum detected positive infection in 30, 19 and 18 mosquitoes respectively; whereas Cytb-PCR detected 27, 16 and 16 infections, respectively. The comparison revealed a close agreement between the two assays (kappa = 0.862, 0.842 and 0.894, respectively for Pv-210, Pv-247 and P. falciparum groups). It was found that the eight CS-ELISA-positive mosquitoes detected negative by Cytb-PCR were false-positive results. The lowest detection limit of this Cytb-PCR was 10 sporozoites. A highly concordance result was also found between nested PCR and Cytb-PCR using 107 field caught mosquitoes, and both tests concordantly detected P. falciparum in an Anopheles punctulatus mosquito collected from Kaboibus. Both tests thus suggested an overall sporozoite rate of 0.9% (1/107) in the study areas. Subsequently, PCR-RFLP efficiently discriminated P. falciparum from P. vivax for all of the Cytb-PCR positive samples. CONCLUSION: A single step PCR based method has been introduced here that is highly sensitive, efficient and reliable for identifying P. vivax and P. falciparum from mosquitoes. The reliability of the technique was confirmed by its ability to detect Plasmodium as efficiently as those of CS-ELISA and nested PCR. Application of the assay offers the opportunity to detect vector species of Papua New Guinea and may contribute for designing further vector control programmes.


Subject(s)
Anopheles/parasitology , Plasmodium falciparum/classification , Plasmodium falciparum/isolation & purification , Plasmodium vivax/classification , Plasmodium vivax/isolation & purification , Polymerase Chain Reaction/methods , Animals , Cytochromes b/genetics , DNA, Mitochondrial/genetics , DNA, Protozoan/genetics , Papua New Guinea , Sensitivity and Specificity
19.
Korean J Parasitol ; 47(1): 1-5, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19290084

ABSTRACT

A mathematical model for transmission of schistosomes is useful to predict effects of various control measures on suppression of these parasites. This review focuses on epidemiological and environmental factors in Schistosoma japonicum and Schistosoma mekongi infections and recent advances in mathematical models of Schistosoma transmission.


Subject(s)
Communicable Disease Control , Schistosoma/physiology , Schistosomiasis/transmission , Animals , Asia, Southeastern/epidemiology , Disease Reservoirs/parasitology , Humans , Models, Theoretical , Schistosomiasis/epidemiology , Schistosomiasis/parasitology
20.
Exp Parasitol ; 121(2): 144-50, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19017530

ABSTRACT

Reliable analytical techniques to test growth-promoting and antimalarial efficacy on plasmodia are very important. Flow cytometry (FCM) offers the possibility to study developmental stages of intraerythrocytic growth of malaria parasites using nucleic acid staining. To analyze the growth of Plasmodium falciparum SYBR Green I was introduced as an intercalating dye with FCM for the 488nm line of an argon laser. Procedures employing FCM, including fixatives, dye concentrations, dilution buffer, and staining period, were optimized to simplify the method. FCM as described here allows parasitemia and parasites of different stages to be quantified according to the DNA content. The proportion of parasitized erythrocytes estimated by FCM and the Giemsa method agreed with determination by parasite lactate dehydrogenase. The protocol was extended to merozoite counting as a sensitive assay of growth inhibition of the parasite.


Subject(s)
Erythrocytes/parasitology , Flow Cytometry/methods , Fluorescent Dyes , Organic Chemicals , Plasmodium falciparum/growth & development , Animals , Benzothiazoles , Diamines , Flow Cytometry/instrumentation , L-Lactate Dehydrogenase/analysis , Plasmodium falciparum/enzymology , Quinolines , Sensitivity and Specificity
SELECTION OF CITATIONS
SEARCH DETAIL
...