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1.
PLoS Negl Trop Dis ; 15(10): e0009838, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34705823

RESUMO

The sequence diversity of natural and laboratory populations of Brugia pahangi and Brugia malayi was assessed with Illumina resequencing followed by mapping in order to identify single nucleotide variants and insertions/deletions. In natural and laboratory Brugia populations, there is a lack of sequence diversity on chromosome X relative to the autosomes (πX/πA = 0.2), which is lower than the expected (πX/πA = 0.75). A reduction in diversity is also observed in other filarial nematodes with neo-X chromosome fusions in the genera Onchocerca and Wuchereria, but not those without neo-X chromosome fusions in the genera Loa and Dirofilaria. In the species with neo-X chromosome fusions, chromosome X is abnormally large, containing a third of the genetic material such that a sizable portion of the genome is lacking sequence diversity. Such profound differences in genetic diversity can be consequential, having been associated with drug resistance and adaptability, with the potential to affect filarial eradication.


Assuntos
Brugia/genética , Variação Genética , Cromossomo X/genética , Animais , Brugia/classificação , Aberrações Cromossômicas , Genoma Helmíntico
2.
Acta Trop ; 211: 105596, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32589995

RESUMO

Zoonotic cases of Plasmodium knowlesi account for most malaria cases in Malaysia, and humans infected with P. cynomolgi, another parasite of macaques have recently been reported in Sarawak. To date the epidemiology of malaria in its natural Macaca reservoir hosts remains little investigated. In this study we surveyed the prevalence of simian malaria in wild macaques of three states in Peninsular Malaysia, namely Pahang, Perak and Johor using blood samples from 103 wild macaques (collected by the Department of Wildlife and National Parks Peninsular Malaysia) subjected to microscopic examination and nested PCR targeting the Plasmodium small subunit ribosomal RNA gene. As expected, PCR analysis yielded significantly higher prevalence (64/103) as compared to microscopic examination (27/103). No relationship between the age and/or sex of the macaques with the parasitaemia and the Plasmodium species infecting the macaques could be identified. Wild macaques in Pahang had the highest prevalence of Plasmodium parasites (89.7%), followed by those of Perak (69.2%) and Johor (28.9%). Plasmodium inui and P. cynomolgi were the two most prevalent species infecting the macaques from all three states. Half of the macaques (33/64) harboured two or more Plasmodium species. These data provide a baseline survey, which should be extended by further longitudinal investigations that should be associated with studies on the bionomics of the anopheline vectors. This information will allow an accurate evaluation of the risk of zoonotic transmission to humans, and to elaborate effective strategies to control simian malaria.


Assuntos
Macaca/parasitologia , Malária/veterinária , Doenças dos Macacos/parasitologia , Animais , Humanos , Malária/epidemiologia , Malária/parasitologia , Malásia/epidemiologia , Doenças dos Macacos/epidemiologia , Reação em Cadeia da Polimerase
3.
Parasit Vectors ; 9(1): 525, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27688040

RESUMO

BACKGROUND: Anopheles mosquitoes transmit malaria which is one of the world's most threatening diseases. Anopheles dirus (sensu stricto) is among the main vectors of malaria in South East Asia. The mosquito innate immune response is the first line of defence against malaria parasites during its development. The immune deficiency (IMD) pathway, a conserved immune signaling pathway, influences anti-Plasmodium falciparum activity in Anopheles gambiae, An. stephensi and An. albimanus. The aim of the study was to determine the role of Rel2, an IMD pathway-controlled NF-kappaß transcription factor, in An. dirus. METHODS: RACE (Rapid amplification of cDNA ends) was performed on the Rel2 gene. Double-stranded Rel2 was constructed and injected into the thorax of female mosquitoes. The injected mosquitoes were fed on a P. falciparum gametocyte culture and dissected on day 7-9 post-feeding in order to count the oocysts. A survival analysis was conducted by exposing the dsRNA injected mosquitoes to Gram-positive and Gram-negative bacteria. RESULTS: This study demonstrated that the Rel2 gene in An. dirus has two isoforms, short length and full length. RNA interference-mediated gene silencing of Rel2 showed that the latter is involved in protection against P. falciparum, Gram-positive bacteria (Micrococcus luteus) with Lys-type peptidoglycan and Gram-negative bacteria (Escherichia coli) with DAP-type peptidoglycan. CONCLUSION: This study suggested that there are similarities in the splicing events and functionality of the Rel2 gene, between the Anopheles species. Among all the important anophelines, the immunity of only a few has been thoroughly investigated. In order to develop novel vector-based control strategies and restrict malaria transmission, the immune pathways of these important vectors should be thoroughly investigated.

4.
Am J Trop Med Hyg ; 95(4): 874-876, 2016 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-27481059

RESUMO

In this study, the seroprevalence of sparganosis and its relationship with sociodemographic factors in northern Tanzania have been assessed. A total of 216 serum samples from two rural districts, Monduli and Babati, were tested for sparganosis using an enzyme-linked immunosorbent assay. The seroprevalence of anti-sparganum IgG antibodies was 62.5% (95% confidence interval [CI] = 56.1-68.9) in all age groups. There were significant associations between district (relative risk [RR] = 1.95, 95% CI = 1.42-2.69), education (RR = 1.40, 95% CI = 1.15-1.70), and pet ownership with seropositivity (RR = 1.48, 95% CI = 1.02-2.16) based on univariate analysis. However, only the district was significantly associated with seropositivity (odds ratio = 4.20, 95% CI = 1.89-9.32) in binary logistic regression analysis. Providing health education to people residing in sparganosis-endemic areas is likely to improve the efficacy of preventative measures and reduce human disease burden.


Assuntos
Anticorpos Anti-Helmínticos/imunologia , Imunoglobulina G/imunologia , População Rural/estatística & dados numéricos , Esparganose/epidemiologia , Animais , Escolaridade , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Animais de Estimação , Fatores de Risco , Estudos Soroepidemiológicos , Esparganose/imunologia , Plerocercoide/imunologia , Tanzânia/epidemiologia
5.
Parasit Vectors ; 7: 505, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25388913

RESUMO

BACKGROUND: The neglected tropical diseases, echinococcosis, schistosomiasis and toxoplasmosis are all globally widespread zoonotic diseases with potentially harmful consequences. There is very limited data available on the prevalence of these infections, except for schistosmiasis, in underdeveloped countries. This study aimed to determine the seroprevalence of Echinococcus multilocularis, Schistosoma mansoni, and Toxoplasma gondii antibodies in populations from the Monduli and Babati districts in Tanzania. METHODS: A total of 345 blood samples were collected from 160 and 185 randomly selected households from Babati and Monduli districts, Tanzania between February and May of 2012 and analyzed them using the enzyme linked immunosorbent assay. The antibodies were determined using the NovaLisa® Toxoplasma gondii IgG, NovaLisa® Schistosoma Mansoni IgG, NovaLisa® Echinococcus IgG and NovaLisa® Toxoplasma gondii IgM kits (Novatec, Germany). RESULTS: The seropositivity estimated for E. multilocularis, S. mansoni, and T. gondii IgG was 11.3% (95% confidence interval (CI): 7.96-14.6), 51.3% (95% CI: 46.0-56.5), and 57.68% (95% CI: 52.5-62.9), respectively. The seropositivity for T. gondii IgM was 11.3% (95% CI: 7.96-14.6). Living in the Monduli district was found to be the main risk factor for IgG seropositivity for both schistosomiasis (OR =1.94; 95% CI: 1.23-3.08; p =0.005) and toxoplasmosis (OR =2.09; 95% CI: 1.31-3.33; p =0.002). CONCLUSIONS: These results suggest that restricting disease transmission, implementing control measures, and introducing training projects to increase public awareness are imperative, particularly for the Monduli district.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Anticorpos Antiprotozoários/sangue , Equinococose/sangue , Esquistossomose/sangue , Toxoplasmose/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Equinococose/epidemiologia , Echinococcus/imunologia , Echinococcus/isolamento & purificação , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Saúde da População Rural , Schistosoma mansoni/imunologia , Schistosoma mansoni/isolamento & purificação , Esquistossomose/epidemiologia , Estudos Soroepidemiológicos , Tanzânia/epidemiologia , Toxoplasma/imunologia , Toxoplasma/isolamento & purificação , Toxoplasmose/epidemiologia , Adulto Jovem
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