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1.
Adv Parasitol ; 104: 247-326, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31030770

RESUMO

Soil-transmitted helminth (STH) infections represent a major public health problem globally, particularly among socio-economically disadvantaged populations. Detection of STH infections is often challenging, requiring a combination of diagnostic techniques to achieve acceptable sensitivity and specificity, particularly in low infection-intensity situations. The microscopy-based Kato-Katz remains the most widely used method but has low sensitivity in the detection of, for instance, Strongyloides spp. infections, among others. Antigen/antibody assays can be more sensitive but are parasite species-specific. Highly sensitive PCR methods have been developed to be multiplexed to allow multi-species detection. Novel diagnostic tests for all STH species are needed for effective monitoring, evaluation of chemotherapy programmes, and to assess the potential emergence of parasite resistance. This review discusses available diagnostic methods for the different stages of STH control programmes, which vary in sensitivity and spectrum of detection requirements, and tools to evaluate drug efficacy and resistance.

2.
Infect Dis Poverty ; 7(1): 121, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30526666

RESUMO

BACKGROUND: Co-parasitism is a frequent occurrence in impoverished communities in the tropics resulting in a considerable disease burden. While there are extensive reports of intestinal helminthiases, including schistosomiasis japonica, the occurrence and extent of diseases caused by intestinal protozoa (IP) have yet to be investigated in depth in the Philippines. We present a detailed analysis of polyparasitism in a rural community of Northern Samar, focusing on co-infections of IP with Schistosoma japonicum. METHODS: A descriptive cross sectional study was carried out in 2015 across 18 barangays (villages) endemic for S. japonicum in Northern Samar, the Philippines to assess the burden of human schistosomiasis and IP infections. Faecal samples collected from 412 participants from the 18 barangays were included in the final molecular analysis. A multiplex quantitative PCR assay was developed and used for the detection of Blastocystis spp., Entamoeba histolytica, Cryptosporidium spp. and Giardia duodenalis in stool samples. The findings were combined with previous results of droplet digital PCR diagnosis of individuals from the same 18 barangays infected with S. japonicum determined using the same stool samples for analysis. RESULTS: Mean age of the study participants was 40.3 years (95% CI: 38.8-41.8) with 53% (n = 218) being males. Prevalence of S. japonicum (74.5%) and Blastocystis spp. (58.7%) was significantly higher compared to other infections, with E. histolytica having the lowest prevalence (12.1%). A majority of individuals were infected with more than one parasite with two infections being most common (n = 175, 42.5%). The prevalence of individuals with two parasites was significantly higher than all others with 27.9% (n = 115) subjects harbouring a single parasite species. Of individuals with two infections, S. japonicum and Blastocystis spp. were the most common combination (n = 110, 62.9%). Examining age within the population, 58.5% (n = 38) of school-aged children and 60.1% (n = 14) of women of child bearing age harboured at least two parasite species. CONCLUSIONS: The study revealed that polyparasitism with IP infections and schistosomiasis japonica is highly prevalent in individuals in Northern Samar which likely contributes to the significant public health and socio-economic burden suffered by this population. More generally, the findings are of relevance when considering implementation of integrated control strategies for intestinal parasites.


Assuntos
Coinfecção , Enteropatias Parasitárias/complicações , Infecções por Protozoários/complicações , População Rural , Esquistossomose Japônica/complicações , Adolescente , Adulto , Criança , Feminino , Humanos , Enteropatias Parasitárias/epidemiologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Filipinas , Prevalência , Infecções por Protozoários/epidemiologia , Fatores de Risco , Esquistossomose Japônica/epidemiologia , Adulto Jovem
3.
Trop Med Infect Dis ; 3(2)2018 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-30274454

RESUMO

Lymphatic filariasis (LF) infects an estimated 120 million people worldwide, with a further 856 million considered at risk of infection and requiring preventative chemotherapy. The majority of LF infections are caused by Wuchereria bancrofti, named in honour of the Australian physician Joseph Bancroft, with the remainder due to Brugia malayi and B. timori. Infection with LF through the bite of an infected mosquito, can lead to the development of the condition known as elephantiasis, where swelling due to oedema leads to loss of function in the affected area and thickening of the skin, 'like an elephant'. LF has previously been endemic in Australia, although currently, no autochthonous cases occur there. Human immigration to Australia from LF-endemic countries, including those close to Australia, and the presence of susceptible mosquitoes that can act as suitable vectors, heighten the possibility of the reintroduction of LF into this country. In this review, we examine the history of LF in Australia and Oceania and weigh up the potential risk of its re-occurrence on mainland Australia.

4.
Trop Med Infect Dis ; 3(3)2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30274477

RESUMO

Despite extensive efforts over the last few decades, the global disease burden of schistosomiasis still remains unacceptably high. This could partly be attributed to the lack of accurate diagnostic tools for detecting human and animal schistosome infections in endemic areas. In low transmission and low prevalence areas where schistosomiasis elimination is targeted, case detection requires a test that is highly sensitive. Diagnostic tests with low sensitivity will miss individuals with low infection intensity and these will continue to contribute to transmission, thereby interfering with the efficacy of the control measures operating. Of the many diagnostic approaches undertaken to date, the detection of schistosome DNA using DNA amplification techniques including polymerase chain reaction (PCR) provide valuable adjuncts to more conventional microscopic and serological methods, due their accuracy, high sensitivity, and the capacity to detect early pre-patent infections. Furthermore, DNA-based methods represent important screening tools, particularly in those endemic areas with ongoing control where infection prevalence and intensity have been reduced to very low levels. Here we review the role of DNA diagnostics in the path towards the control and elimination of schistosomiasis.

5.
Infect Dis Poverty ; 7(1): 8, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29394958

RESUMO

BACKGROUND: Schistosomiasis in the People's Republic of China (PRC) can be traced back to antiquity. In the past 60 years, the Chinese government has made great efforts to control this persistent disease with elimination slated by 2020 through the implementation of a comprehensive control strategy. This strategy aims to reduce the role of bovines and humans as sources of infection as a pre-requisite for elimination through transmission interruption. The goal of elimination will be achievable only by the implementation of a sustainable surveillance and control system, with sensitive diagnosis a key feature so that the true disease burden is not underestimated. Currently used diagnostics lack the necessary sensitivity to accurately determine the prevalence of Schistosoma japonicum infection in areas with low infection intensities. It is of critical importance to find and treat people and to identify animals with low-level infections if the National Control Programme for China is to achieve schistosomiasis elimination. METHODS: We evaluated a real-time polymerase chain reaction (qPCR) assay using 633 human stool samples collected from five villages in Hunan, Anhui, Hubei, and Jiangxi provinces, and 182 bovine (70 cattle and 112 buffalo) stool samples obtained from four villages in Hunan, Anhui, and Jiangxi provinces in the PRC. All stool samples were subjected to the miracidium hatching test (MHT, a diagnostic procedure used in the National Schistosomiasis Control Programme) and the qPCR assay. Samples positive by MHT were subjected to either the Kato-Katz technique for humans, or the formalin-ethyl acetate sedimentation-digestion (FEA-SD) procedure for bovines, to determine infection intensities. RESULTS: The qPCR assay exhibited a high level of sensitivity in the detection of S. japonicum infections. With both the human and bovine samples, a significantly higher prevalence was determined using the qPCR assay (11.06% humans, 24.73% bovines) than with the MHT (0.93% humans, 7.69% bovines). The animal contamination index (calculated using data obtained with the qPCR technique) for all positive bovines was 27 618 000 eggs per day, indicating a considerable amount of environmental egg contamination that would be underestimated using less sensitive diagnostic procedures. CONCLUSIONS: The qPCR assay we have evaluated will be applicable as a future field diagnostic and surveillance tool in low-transmission zones where schistosomiasis elimination is targeted and for monitoring post-intervention areas to verify that elimination has been maintained.


Assuntos
Doenças dos Bovinos/diagnóstico , Fezes/parasitologia , Schistosoma japonicum/genética , Esquistossomose Japônica/diagnóstico , Esquistossomose Japônica/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , China/epidemiologia , Humanos , Contagem de Ovos de Parasitas , Prevalência , Reação em Cadeia da Polimerase em Tempo Real/métodos , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/transmissão , Esquistossomose Japônica/veterinária
6.
PLoS Negl Trop Dis ; 11(11): e0006022, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29108026

RESUMO

BACKGROUND: Soil-transmitted helminths (STH) are the most common parasitic infections in impoverished communities, particularly among children. Current STH control is through school-based mass drug administration (MDA), which in the Philippines is done twice annually. As expected, MDA has decreased the intensity and prevalence of STH over time. As a result, the common Kato Katz (KK) thick smear method of detecting STH is less effective because it lacks sensitivity in low intensity infections, making it difficult to measure the impact of deworming programs. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional study was carried out over a four-week period from October 27, 2014 until November 20, 2014 in Laguna province, the Philippines. Stool samples were collected from 263 schoolchildren, to determine the prevalence of STH and compare diagnostic accuracy of multiplex quantitative polymerase chain reaction (qPCR) with the KK. A large discrepancy in the prevalence between the two techniques was noted for the detection of at least one type of STH infection (33.8% by KK vs. 78.3% by qPCR), Ascaris lumbricoides (20.5% by KK vs. 60.8% by qPCR) and Trichuris trichiura (23.6% by KK vs. 38.8% by qPCR). Considering the combined results of both methods, the prevalence of at least one type of helminth infection, A. lumbricoides, and T. trichiura were 83.3%, 67.7%, and 53.6%, respectively. Sensitivity of the qPCR for detecting at least one type of STH infection, A. lumbricoides, and T. trichiura were 94.1%, 89.9%, and 72.3% respectively; whereas KK sensitivity was 40.6%, 30.3%, and 44.0%, respectively. The qPCR method also detected infections with Ancylostoma spp. (4.6%), Necator americanus (2.3%), and Strongyloides stercoralis (0.8%) that were missed by KK. CONCLUSION/SIGNIFICANCE: qPCR may provide new and important diagnostic information to improve assessment of the effectiveness and impact of integrated control strategies particularly in areas where large-scale STH control has led to low prevalence and/or intensity of infection.


Assuntos
Ascaríase/diagnóstico , Ascaríase/epidemiologia , Ascaris lumbricoides/isolamento & purificação , Solo/parasitologia , Tricuríase/diagnóstico , Tricuríase/epidemiologia , Animais , Ascaríase/parasitologia , Criança , Estudos Transversais , Fezes/parasitologia , Feminino , Humanos , Masculino , Contagem de Ovos de Parasitas , Filipinas/epidemiologia , Prevalência , Instituições Acadêmicas , Sensibilidade e Especificidade , Tricuríase/parasitologia , Trichuris/isolamento & purificação
7.
J Infect Dis ; 216(12): 1611-1622, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29029307

RESUMO

Background: Schistosomiasis japonica remains a major public health and socioeconomic concern in Southeast Asia. Sensitive and accurate diagnostics can play a pivotal role in achieving disease elimination goals. Methods: We previously reported a novel droplet digital polymerase chain reaction (ddPCR) assay targeting the mitochondrial gene nad1 to diagnose schistosomiasis japonica. The tool identified both prepatent and patent infections using Schistosoma japonicum DNA isolated from serum, urine, salivary glands, and feces in a murine model. The assay was validated here using clinical samples collected from 412 subjects resident in an area moderately endemic for schistosomiasis in the Philippines. Results: S. japonicum DNA present in human stool, serum, urine, and saliva was detected quantitatively with high sensitivity. The capability to diagnose cases of human schistosomiasis using noninvasively collected clinical samples, the higher level of sensitivity obtained compared with the microscopy-based Kato-Katz test, and the capacity to quantify infection intensity have important public health implications for schistosomiasis control and programs targeting other neglected tropical diseases. Conclusions: This verified ddPCR method represents a valuable new tool for the diagnosis and surveillance of schistosomiasis, particularly in low-prevalence and low-intensity areas approaching elimination and in monitoring where disease emergence or re-emergence is a concern.

8.
Parasitology ; 144(12): 1633-1642, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28637527

RESUMO

Schistosomiasis in China has been substantially reduced due to an effective control programme employing various measures including bovine and human chemotherapy, and the removal of bovines from endemic areas. To fulfil elimination targets, it will be necessary to identify other possible reservoir hosts for Schistosoma japonicum and include them in future control efforts. This study determined the infection prevalence of S. japonicum in rodents (0-9·21%), dogs (0-18·37%) and goats (6·9-46·4%) from the Dongting Lake area of Hunan province, using a combination of traditional coproparasitological techniques (miracidial hatching technique and Kato-Katz thick smear technique) and molecular methods [quantitative real-time PCR (qPCR) and droplet digital PCR (ddPCR)]. We found a much higher prevalence in goats than previously recorded in this setting. Cattle and water buffalo were also examined using the same procedures and all were found to be infected, emphasising the occurrence of active transmission. qPCR and ddPCR were much more sensitive than the coproparasitological procedures with both KK and MHT considerably underestimating the true prevalence in all animals surveyed. The high level of S. japonicum prevalence in goats indicates that they are likely important reservoirs in schistosomiasis transmission, necessitating their inclusion as targets of control, if the goal of elimination is to be achieved in China.


Assuntos
Búfalos , Doenças dos Bovinos/transmissão , Doenças do Cão/transmissão , Doenças das Cabras/transmissão , Doenças dos Roedores/transmissão , Esquistossomose/veterinária , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , China/epidemiologia , Doenças do Cão/epidemiologia , Cães , Fezes/parasitologia , Doenças das Cabras/epidemiologia , Cabras , Reação em Cadeia da Polimerase , Prevalência , Doenças dos Roedores/epidemiologia , Roedores , Esquistossomose/epidemiologia , Esquistossomose/transmissão
9.
Oncotarget ; 8(18): 29935-29950, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28404898

RESUMO

We have previously identified nucleolar and spindle associated protein 1 (NUSAP1) as a prognostic biomarker in early stage prostate cancer. To better understand the role of NUSAP1 in prostate cancer progression, we tested the effects of increased and decreased NUSAP1 expression in cell lines, in vivo models, and patient samples. NUSAP1 promotes invasion, migration, and metastasis, possibly by modulating family with sequence similarity 101 member B (FAM101B), a transforming growth factor beta 1 (TGFß1) signaling effector involved in the epithelial to mesenchymal transition. Our findings provide insights into the importance of NUSAP1 in prostate cancer progression and provide a rationale for further study of NUSAP1 function, regulation, and clinical utility.


Assuntos
Biomarcadores Tumorais , Proteínas Associadas aos Microtúbulos/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Animais , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Modelos Animais de Doenças , Progressão da Doença , Expressão Gênica , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias da Próstata/metabolismo
10.
Parasitology ; 144(8): 1005-1015, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28274280

RESUMO

The current World Health Organization strategic plan targets the elimination of schistosomiasis as a public health problem by 2025 and accurate diagnostics will play a pivotal role in achieving this goal. DNA-based detection methods provide a viable alternative to some of the commonly used tests, notably microscopy and serology, for the diagnosis of schistosomiasis. The detection of parasite cell-free DNA in different clinical samples is a recent valuable advance, which provides significant benefits for accurate disease diagnosis. Here we validated a novel duplex droplet digital PCR assay for the diagnosis of Chinese (SjC) and Philippine (SjP) strains of Schistosoma japonicum infection in a mouse model. The assay proved applicable for both SjC and SjP infections and capable of detecting infection at a very early intra-mammalian stage in conveniently obtainable samples (urine and saliva) as well as in serum and feces. The target DNA copy numbers obtained in the assay showed a positive correlation with the infection burden assessed by direct traditional parasitology. The potential to detect parasite DNA in urine and saliva has important practical implications for large-scale epidemiological screening programmes in the future, particularly in terms of logistical convenience, and the assay has the potential to be a valuable additional tool for the diagnosis of schistosomiasis japonica.


Assuntos
Variações do Número de Cópias de DNA , DNA de Helmintos/análise , Reação em Cadeia da Polimerase/métodos , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/diagnóstico , Animais , Sangue/parasitologia , China , Modelos Animais de Doenças , Fezes/parasitologia , Feminino , Humanos , Camundongos , Filipinas , Saliva/parasitologia , Esquistossomose Japônica/parasitologia , Sensibilidade e Especificidade , Urina/parasitologia
11.
Trop Med Infect Dis ; 2(4)2017 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30270913

RESUMO

Soil-transmitted helminths (STH) infect 2 billion people worldwide including significant numbers in South-East Asia (SEA). In Australia, STH are of less concern; however, indigenous communities are endemic for STH, including Strongyloides stercoralis, as well as for serious clinical infections due to other helminths such as Toxocara spp. The zoonotic hookworm Ancylostoma ceylanicum is also present in Australia and SEA, and may contribute to human infections particularly among pet owners. High human immigration rates to Australia from SEA, which is highly endemic for STH Strongyloides and Toxocara, has resulted in a high prevalence of these helminthic infections in immigrant communities, particularly since such individuals are not screened for worm infections upon entry. In this review, we consider the current state of STH infections in Australia and SEA.

12.
Adv Parasitol ; 91: 311-97, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27015952

RESUMO

Zoonotic parasitic diseases are increasingly impacting human populations due to the effects of globalization, urbanization and climate change. Here we review the recent literature on the most important helminth zoonoses, including reports of incidence and prevalence. We discuss those helminth diseases which are increasing in endemic areas and consider their geographical spread into new regions within the framework of globalization, urbanization and climate change to determine the effect these variables are having on disease incidence, transmission and the associated challenges presented for public health initiatives, including control and elimination.


Assuntos
Mudança Climática , Helmintíase/epidemiologia , Internacionalidade , Urbanização , Zoonoses/epidemiologia , Animais , Humanos
13.
J Microbiol Methods ; 125: 19-27, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27021661

RESUMO

Schistosomiasis is a chronically debilitating helminth infection with a significant socio-economic and public health impact. Accurate diagnostics play a pivotal role in achieving current schistosomiasis control and elimination goals. However, many of the current diagnostic procedures, which rely on detection of schistosome eggs, have major limitations including lack of accuracy and the inability to detect pre-patent infections. DNA-based detection methods provide a viable alternative to the current tests commonly used for schistosomiasis diagnosis. Here we describe the optimisation of a novel droplet digital PCR (ddPCR) duplex assay for the diagnosis of Schistosoma japonicum infection which provides improved detection sensitivity and specificity. The assay involves the amplification of two specific and abundant target gene sequences in S. japonicum; a retrotransposon (SjR2) and a portion of a mitochondrial gene (nad1). The assay detected target sequences in different sources of schistosome DNA isolated from adult worms, schistosomules and eggs, and exhibits a high level of specificity, thereby representing an ideal tool for the detection of low levels of parasite DNA in different clinical samples including parasite cell free DNA in the host circulation and other bodily fluids. Moreover, being quantitative, the assay can be used to determine parasite infection intensity and, could provide an important tool for the detection of low intensity infections in low prevalence schistosomiasis-endemic areas.


Assuntos
DNA de Helmintos/análise , Reação em Cadeia da Polimerase/métodos , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/diagnóstico , Adulto , Animais , DNA de Helmintos/metabolismo , Fezes/parasitologia , Corantes Fluorescentes , Genes de Helmintos , Genes Mitocondriais , Humanos , Retroelementos , Schistosoma japonicum/genética , Schistosoma japonicum/crescimento & desenvolvimento , Esquistossomose Japônica/parasitologia , Sensibilidade e Especificidade
14.
Environ Sci Technol ; 50(7): 3572-9, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26963686

RESUMO

Atmospheric models of secondary organic aerosol (SOA) typically assume organic species form a well-mixed phase. As a result, partitioning of semivolatile oxidation products into the particle phase to form SOA is thought to be enhanced by preexisting organic particles. In this work, the physicochemical properties that govern such enhancement in SOA yield were examined. SOA yields from α-pinene ozonolysis were measured in the presence of a variety of organic seeds which were chosen based on polarity and phase state at room temperature. Yield enhancement was only observed with seeds of medium polarities (tetraethylene glycol and citric acid). Solid hexadecanol seed was observed to enhance SOA yields only in chamber experiments with longer mixing time scales, suggesting that the mixing process for SOA and hexadecanol may be kinetically limited at shorter time scales. Our observations indicate that, in addition to kinetic limitations, intermolecular interactions also play a significant role in determining SOA yields. Here we propose for the first time to use the Hansen solubility framework to determine aerosol miscibility and predict SOA yield enhancement. These results highlight that current models may overestimate SOA formation, and parametrization of intermolecular forces is needed for accurate predictions of SOA formation.


Assuntos
Aerossóis/química , Compostos Orgânicos/química , Cinética , Modelos Teóricos , Monoterpenos/química , Ozônio/química , Solubilidade , Termodinâmica
15.
Int J Parasitol ; 45(7): 477-83, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25858090

RESUMO

The global socioeconomic importance of helminth parasitic disease is underpinned by the considerable clinical impact on millions of people. While helminth polyparasitism is considered common in the Philippines, little has been done to survey its extent in endemic communities. High morphological similarity of eggs between related species complicates conventional microscopic diagnostic methods which are known to lack sensitivity, particularly in low intensity infections. Multiplex quantitative PCR diagnostic methods can provide rapid, simultaneous identification of multiple helminth species from a single stool sample. We describe a multiplex assay for the differentiation of Ascaris lumbricoides, Necator americanus, Ancylostoma, Taenia saginata and Taenia solium, building on our previously published findings for Schistosoma japonicum. Of 545 human faecal samples examined, 46.6% were positive for at least three different parasite species. High prevalences of S. japonicum (90.64%), A. lumbricoides (58.17%), T. saginata (42.57%) and A. duodenale (48.07%) were recorded. Neither T. solium nor N. americanus were found to be present. The utility of molecular diagnostic methods for monitoring helminth parasite prevalence provides new information on the extent of polyparasitism in the Philippines municipality of Palapag. These methods and findings have potential global implications for the monitoring of neglected tropical diseases and control measures.


Assuntos
Helmintíase/epidemiologia , Helmintíase/parasitologia , Enteropatias Parasitárias/parasitologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Enteropatias Parasitárias/epidemiologia , Masculino , Pessoa de Meia-Idade , Filipinas/epidemiologia , Adulto Jovem
16.
PLoS Negl Trop Dis ; 9(2): e0003108, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25643317

RESUMO

The cause of zoonotic schistosomiasis in the Philippines is Schistosoma japonicum, which infects up to 46 mammalian hosts, including humans and bovines. In China, water buffaloes have been identified as major reservoir hosts for schistosomiasis japonica, contributing up to 75% of human transmission. In the Philippines, water buffaloes (carabao; Bubalus bubalis carabanesis) have, historically, been considered unimportant reservoirs. We therefore revisited the possible role of bovines in schistosome transmission in the Philippines, using the recently described formalin-ethyl acetate sedimentation (FEA-SD) technique and a qPCR assay to examine fecal samples from 153 bovines (both carabao and cattle) from six barangays in Northern Samar. A high prevalence of S. japonicum was found using qPCR and FEA-SD in both cattle (87.50% and 77.08%, respectively) and carabao (80.00% and 55.24%, respectively). The average daily egg output for each bovine was calculated at 195,000. High prevalence and infection intensity of F. gigantica was also found in the bovines by qPCR and FEA-SD (95.33% and 96.00%, respectively). The identification of bovines as major reservoir hosts for S. japonicum transmission suggests that bovine treatment and/or vaccination, as one becomes available, should be included in any future control program that aims to reduce the disease burden due to schistosomiasis in the Philippines.


Assuntos
Doenças dos Bovinos/epidemiologia , Fasciola/isolamento & purificação , Fasciolíase/veterinária , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/veterinária , Zoonoses/epidemiologia , Animais , Búfalos/parasitologia , Bovinos , Doenças dos Bovinos/transmissão , China/epidemiologia , Fasciolíase/epidemiologia , Fasciolíase/transmissão , Fezes/parasitologia , Humanos , Filipinas/epidemiologia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Esquistossomose Japônica/epidemiologia , Esquistossomose Japônica/transmissão , Zoonoses/parasitologia , Zoonoses/transmissão
17.
PLoS Negl Trop Dis ; 9(1): e0003483, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25606851

RESUMO

BACKGROUND: The Philippines has a population of approximately 103 million people, of which 6.7 million live in schistosomiasis-endemic areas with 1.8 million people being at risk of infection with Schistosoma japonicum. Although the country-wide prevalence of schistosomiasis japonica in the Philippines is relatively low, the prevalence of schistosomiasis can be high, approaching 65% in some endemic areas. Of the currently available microscopy-based diagnostic techniques for detecting schistosome infections in the Philippines and elsewhere, most exhibit varying diagnostic performances, with the Kato-Katz (KK) method having particularly poor sensitivity for detecting low intensity infections. This suggests that the actual prevalence of schistosomiasis japonica may be much higher than previous reports have indicated. METHODOLOGY/PRINCIPAL FINDINGS: Six barangay (villages) were selected to determine the prevalence of S. japonicum in humans in the municipality of Palapag, Northern Samar. Fecal samples were collected from 560 humans and examined by the KK method and a validated real-time PCR (qPCR) assay. A high S. japonicum prevalence (90.2%) was revealed using qPCR whereas the KK method indicated a lower prevalence (22.9%). The geometric mean eggs per gram (GMEPG) determined by the qPCR was 36.5 and 11.5 by the KK. These results, particularly those obtained by the qPCR, indicate that the prevalence of schistosomiasis in this region of the Philippines is much higher than historically reported. CONCLUSIONS/SIGNIFICANCE: Despite being more expensive, qPCR can complement the KK procedure, particularly for surveillance and monitoring of areas where extensive schistosomiasis control has led to low prevalence and intensity infections and where schistosomiasis elimination is on the horizon, as for example in southern China.


Assuntos
Reação em Cadeia da Polimerase em Tempo Real/métodos , Esquistossomose Japônica/epidemiologia , Adolescente , Adulto , Idoso , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Filipinas/epidemiologia , Prevalência , Esquistossomose Japônica/prevenção & controle
18.
Prostate ; 75(5): 517-26, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25585568

RESUMO

BACKGROUND: Overexpression of NUSAP1 is associated with poor prognosis in prostate cancer, but little is known about what leads to its overexpression. Based on previous observations that NUSAP1 expression is enhanced by E2F1, we hypothesized that NUSAP1 expression is regulated, at least in part, by loss of RB1 via the RB1/E2F1 axis. METHODS: Using Significance Analysis of Microarrays, we examined RB1, E2F1, and NUSAP1 transcript levels in prostate cancer gene expression datasets. We compared NUSAP1 expression levels in DU145, LNCaP, and PC-3 prostate cancer cell lines via use of cDNA microarray data, RT-qPCR, and Western blots. In addition, we used lentiviral expression constructs to knockdown RB1 in prostate cancer cell lines and transient transfections to knockdown E2F1, and investigated RB1, E2F1, and NUSAP1 expression levels with RT-qPCR and Western blots. Finally, in DU145 cells or PC-3 cells that stably underexpress RB1, we used proliferation and invasion assays to assess whether NUSAP1 knockdown affects proliferation or invasion. RESULTS: NUSAP1 transcript levels are positively correlated with E2F1 and negatively correlated with RB1 transcript levels in prostate cancer microarray datasets. NUSAP1 expression is elevated in the RB1-null DU145 prostate cancer cell line, as opposed to LNCaP and PC-3 cell lines. Furthermore, NUSAP1 expression increases upon knockdown of RB1 in prostate cancer cell lines (LNCaP and PC-3) and decreases after knockdown of E2F1. Lastly, knockdown of NUSAP1 in DU145 cells or PC-3 cells with stable knockdown of RB1 decreases proliferation and invasion of these cells. CONCLUSION: Our studies support the notion that NUSAP1 expression is upregulated by loss of RB1 via the RB1/E2F1 axis in prostate cancer cells. Such upregulation may promote prostate cancer progression by increasing proliferation and invasion of prostate cancer cells. NUSAP1 may thus represent a novel therapeutic target.


Assuntos
Regulação Neoplásica da Expressão Gênica/fisiologia , Proteínas Associadas aos Microtúbulos/genética , Neoplasias da Próstata/genética , Proteína do Retinoblastoma/metabolismo , Western Blotting , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células , Fator de Transcrição E2F1/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias da Próstata/patologia , Reação em Cadeia da Polimerase em Tempo Real
19.
Microbes Infect ; 15(13): 858-65, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23973709

RESUMO

Schistosomiasis is a neglected tropical disease with a very long endemic history in Asia. Great strides have been made to control the disease in China and the Philippines but the road to elimination is far from over, given the zoonotic nature of the schistosome parasites in both countries.


Assuntos
Controle de Doenças Transmissíveis/métodos , Erradicação de Doenças , Doenças Endêmicas , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Animais , Ásia/epidemiologia , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/prevenção & controle , Zoonoses/epidemiologia , Zoonoses/prevenção & controle
20.
PLoS One ; 8(7): e69486, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23894490

RESUMO

Inactive DNA methyltransferase (DNMT) 3B splice isoforms are associated with changes in DNA methylation, yet the mechanisms by which they act remain largely unknown. Using biochemical and cell culture assays, we show here that the inactive DNMT3B3 and DNMT3B4 isoforms bind to and regulate the activity of catalytically competent DNMT3A or DNMT3B molecules. DNMT3B3 modestly stimulated the de novo methylation activity of DNMT3A and also counteracted the stimulatory effects of DNMT3L, therefore leading to subtle and contrasting effects on activity. DNMT3B4, by contrast, significantly inhibited de novo DNA methylation by active DNMT3 molecules, most likely due to its ability to reduce the DNA binding affinity of co-complexes, thereby sequestering them away from their substrate. Immunocytochemistry experiments revealed that in addition to their effects on the intrinsic catalytic function of active DNMT3 enzymes, DNMT3B3 and DNMT34 drive distinct types of chromatin compaction and patterns of histone 3 lysine 9 tri-methylation (H3K9me3) deposition. Our findings suggest that regulation of active DNMT3 members through the formation of co-complexes with inactive DNMT3 variants is a general mechanism by which DNMT3 variants function. This may account for some of the changes in DNA methylation patterns observed during development and disease.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , Inativação Gênica , Processamento de RNA , Animais , Linhagem Celular , Cromatina , DNA (Citosina-5-)-Metiltransferases/metabolismo , Histonas/metabolismo , Humanos , Camundongos , Ligação Proteica , Isoformas de Proteínas
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