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1.
Nanomedicine ; 18: 221-233, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30904586

RESUMO

Mosquitoes (Diptera; Culicidae) present a major threat to millions of people and animals worldwide, as they act as vectors for various pathogens, especially parasites and viruses. Resistance to insecticides, such as organophosphates and microbial control agents, and insufficient adherence to application guidelines are common reasons for insecticide treatment failure. Therefore, there is an urgent need for exploration of safer, cheaper, and more effective agents, with novel modes of action, to improve mosquito control. Biosynthesized nanoparticles (NPs) have recently been considered as a potential approach for combating vectors of malaria and also as a treatment for malaria. Here, we present current knowledge about the characterization and effectiveness of biogenic NPs against major vectors of malaria, including avian malaria (which may also provide useful insights on vectors of human malaria). This article is the first systematic review of the effects of biosynthesized nanoparticles on both malaria parasites (Plasmodium spp.) and relevant vectors.


Assuntos
Biotecnologia , Malária/prevenção & controle , Nanotecnologia , Animais , Bactérias/metabolismo , Humanos , Nanopartículas
2.
Parasitol Res ; 117(6): 1717-1727, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29602972

RESUMO

The study of pathogenesis mechanisms of larval stages in the Taeniidae has recently focused on host genetic factors, particularly toll-like receptor (TLR) variations. However, the potential role of TLR4 polymorphism in hydatidosis has not yet been sufficiently elucidated in postoperative patients. In this case-control investigation, 80 patients from Iran, including 40 with acute hydatidosis (AH) and 40 with recurrent hydatidosis (RH), and 80 ethnically matched controls were evaluated from February 2015 to February 2017. Hydatidosis patients were confirmed using radiological, immunological, and histopathological examinations. Genotyping of Asp299Gly and Thr399Ile of TLR4 single-nucleotide polymorphisms was determined by restriction fragment length polymorphism, sequencing, and phylogenetic strategies. The heterozygous mutant-type TLR4 Asp299Gly genotype indicated a tendency to be associated with the occurrence of RH (P = 0.060) and conferred a 3-fold risk for susceptibility. There was no difference in genotype frequency of Asp299Gly between patients with AH and healthy controls (P = 0.42; OR, 1.82; 95% CI, 0.11-30.1%). Interestingly, a frequency of the G allele (12%: Gly) was observed to be a risk factor for susceptibility to RH patients (P = 0.050; OR, 7.08; 95% CI, 0.97-51.5%). A relative genetic variability of TLR4 Asp299Gly was found in RH patients (haplotype diversity: 0.700) compared to AH patients and healthy controls (Hd: 0.000). The Asp299Gly genotype was dominantly identified in patients with hepatic hydatid cysts. The TLR4 Thr399Ile codon was not detected except in a patient with a pulmonary hydatid cyst. The current findings enhance our knowledge regarding the TLR4 Asp299Gly polymorphism potentially leading to the development of RH, by skewing the immune system towards a Th2 response. Identification of the Asp299Gly codon may be a diagnostic hallmark in RH patients who have undergone unsuccessful postoperative intervention. However, further studies with a higher case number are needed on ethnic population from various geographic regions, in order to confirm this hypothesis.


Assuntos
Equinococose/parasitologia , Equinococose/terapia , Echinococcus granulosus/isolamento & purificação , Predisposição Genética para Doença/genética , Receptor 4 Toll-Like/genética , Adulto , Alelos , Animais , Estudos de Casos e Controles , Echinococcus granulosus/genética , Echinococcus granulosus/imunologia , Feminino , Genótipo , Haplótipos/genética , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Filogenia , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , Células Th2/imunologia
3.
Trans R Soc Trop Med Hyg ; 118(4): 293-298, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38141032

RESUMO

BACKGROUND: Microsporidia and Cryptosporidium are obligate intracellular protozoa. These medically important species are recognized as opportunistic organisms in intestinal complications in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome patients. METHODS: The current cross-sectional study was designed and conducted from August 2016 to August 2017 to determine intestinal Cryptosporidium and microsporidia spp. in HIV-infected individuals from the Behavioral Diseases Counseling Center, Tabriz, Iran, by modified acid-fast and modified trichrome staining and nested polymerase chain reaction (PCR) and real-time PCR. RESULTS: Of 100 HIV-infected persons, 21.0% (95% confidence interval [CI] 13.0 to 30.0) and 18.0% (95% CI 11.0 to 26.0) were identified as Cryptosporidium and microsporidia, respectively, by the microscopic method. Of these 100 HIV-infected persons, 18.0% (95% CI 11.0 to 26.0) and 14.0% (95% CI 7.0 to 22.0) were positive for Cryptosporidium and microsporidia, respectively, by the molecular method. The predominant species of microsporidia in patients was Enterocytozoon bieneusi (85.7% [95% CI 57.0 to 98.0]) and Encephalitozoon cuniculi (14.3% [95% CI 1.7 to 42.0]), which were found by quantitative real-time PCR and its high-resolution melting tool. CONCLUSIONS: As far as we know, this study is the first to estimate the prevalence of infection with Cryptosporidium and microsporidia among HIV-infected persons in northwest of Iran. The prevalence of intestinal microsporidiosis and cryptosporidiosis in this area in HIV-infected people was higher than the global prevalence of infection among immunocompromised patients. In addition to the need for further studies to prove protozoan pathogenicity in the aforementioned group, preventive measures should be considered.


Assuntos
Criptosporidiose , Cryptosporidium , Infecções por HIV , Microsporídios , Microsporidiose , Humanos , Cryptosporidium/genética , Criptosporidiose/complicações , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , HIV , Prevalência , Estudos Transversais , Microsporidiose/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real , Fezes/parasitologia
4.
PLoS One ; 18(10): e0292434, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37796859

RESUMO

Cystic echinococcosis (CE) is a life-threatening helminthic disease caused by the Echinococcus granulosus sensulato complex. Previous evidence indicates that the host's innate immune responses against CE can combat and regulate the growth rate and mortality of hydatid cyst in the host's internal organs. However, the survival mechanisms of CE are not yet fully elucidated in the human body. In the present study, the apoptotic effects of fertile and infertile hydatid fluid (HF) were tested on murine peritoneal cells in vivo mice model. Mice were divided into five groups including; control group, fertile HF-treated peritoneal cells, infertile HF-treated peritoneal cells, protoscolices (PSCs)-treated peritoneal cells and HF+PSCs-treated peritoneal cells group. Mice groups were intraperitoneally inoculated with PBS, HF, and/or PSCs. Afterwards, peritoneal cells were isolated and mRNA expression of STAT3, caspase-3, p73 and Smac genes were evaluated by quantitative Real-time PCR. After 48 hours of exposure, the protein levels of Smac and STAT3 was determined by western blotting technique. After 6 hours of exposure, Caspase-3 activity was also measured by fluorometric assay. The intracellular reactive oxygen species (ROS) production was examined in all groups. The mRNA expression levels of p73, caspase-3 and also Caspase-3 activity in HF+PSCs-treated peritoneal cells were higher than in the test and control groups (Pv<0.05), while the mRNA expression level of anti-apoptotic STAT3 and Smac genes in HF+PSC-treated peritoneal cells were lower than in the other groups (Pv<0.05). As well, the level of intracellular ROS in the fertile HCF-treated peritoneal cells, infertile HCF-treated peritoneal cells, PSC-treated peritoneal cells and HF+PSC-treated peritoneal cells groups were significantly higher than in the control group (Pv<0.05).Current findings indicates that oxidative stress and p73 can trigger the apoptosis of murine peritoneal cells through modulator of HF-treated PSCs that is likely one of the hydatid cyst survival mechanisms in vivo mice model.


Assuntos
Apoptose , Equinococose , Echinococcus granulosus , Proteína Tumoral p73 , Animais , Camundongos , Caspase 3/metabolismo , Espécies Reativas de Oxigênio , RNA Mensageiro , Proteína Tumoral p73/metabolismo
5.
AIDS Rev ; 26(3): 105-126, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37879633

RESUMO

People living with HIV (PLWH) constitute a vulnerable population for acquiring additional sexually transmitted infections (STIs). This study was conducted to provide a summary of the evidence on the global prevalence of STIs in PLWH with an emphasis on infectious agents, diagnostic methods, and related risk factors. PubMed, Scopus, and Web of Science were systematically searched to include records published from January 01, 1990, to January 31, 2022, and the Google Scholar search engine was used to check the search strategy. In total, 132 eligible studies reporting STIs in PLWH were included, enrolling subjects from 35 countries across five continents. The pooled proportion of STIs was estimated to be 30.23% (95% CI, 26.1-34.45%) in PLWH and 20.01% (95% CI, 17.17-23.01%) in HIV-negative patients. Our meta-analysis indicated that in PLWH, the pooled OR of STIs compared to HIV-negatives was 1.77 (95% CI: 1.58-1.98) (p < 0.0001). The pooled OR of STIs by viral infectious agents was highest in PLWH (52.19% [95% CI: 43.88-60.43]) compared with fungal (22.19% [95% CI: 15.64-29.53]), bacterial (19.07% [95% CI: 13.59-26.63]), and parasitic (14.05% [95% CI: 11.88-16.38]) infections. Our findings show that there is a rather significant frequency of STIs among PLWH. This study highlights the need for new programs for the detection, treatment, and prevention of STIs in this at-risk population.


Assuntos
Infecções por HIV , Infecções Sexualmente Transmissíveis , Humanos , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Prevalência , Infecções Sexualmente Transmissíveis/complicações , Infecções Sexualmente Transmissíveis/epidemiologia , Fatores de Risco
6.
Acta Trop ; 224: 106156, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34599888

RESUMO

Trichomoniasis, caused by Trichomonas vaginalis (T. vaginalis), is the most common non-viral sexually transmitted disease worldwide. As current trichomoniasis chemotherapies have many side effects, we examined the Anti-Trichomonas effects of nano-liposomal metronidazole (NLMTZ) compared to metronidazole (MTZ) in vitro. Liposomes were produced using the thin film hydration-sonication technique with a slight modification coated with MTZ. The average hydrodynamic diameter of monodispersed NLMTZ was evaluated by DLS and the morphological measurements were performed by scanning electron microscopy (SEM). The effects of NLMTZ and MTZ (5, 10, 20 and 40 µg/mL) on T. vaginalis trophozoites (105 cells/mL) in trypticase-yeast extract-maltose (TYM) medium were evaluated in different exposure times. Then, cell viability, IC50, SEM analysis and the expression of the metacaspase gene were assessed by qRT-PCR. Growth inhibition of MTZ in a concentration of 40 µg/mL was 39.34% after 3 h, whereas NLMTZ caused 51% growth inhibition after 3 h and lysed Trichomonas completely after 12 h. The IC50 values were estimated at 31.51 and 15.90 µg/mL after a 6 h exposure for MTZ and NLMTZ, respectively. Moreover, both T. vaginalis treated with MTZ and NLMTZ had high levels of metacaspase mRNA expression relative to the control groups (P< 0.05). A significant difference was observed between the apoptotic intensities of T. vaginalis treated with MTZ and NLMTZ (P< 0.05). This study showed that nano-liposomal MTZ is a potentially excellent approach for the treatment of trichomoniasis in vitro, although further studies are needed before consideration of clinical trials.


Assuntos
Tricomoníase , Trichomonas vaginalis , Animais , Metronidazol/farmacologia , Trofozoítos
7.
Vet Parasitol ; 281: 109093, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32278149

RESUMO

Cryptosporidiosis, caused by the protozoan parasite Cryptosporidium spp., is an important zoonotic disease and is considered a global public health concern. Dogs are suggested as one of potential reservoirs for transmitting the Cryptosporidium infection to humans. However, there is a paucity of information about global patterns of occurrence of Cryptosporidium in dogs. A systematic review and meta-analysis were carried out to evaluate the global prevalence of Cryptosporidium infection among dogs. In this study, PubMed, Scopus, Web of Science and Google Scholar databases were systematically searched for relevant studies up until October 30, 2019. Finally, 127 articles (including 160 datasets) were eligible for inclusion in the systematic review and meta-analysis. The overall prevalence of Cryptosporidium infection was estimated at 8% (95 % CI: 5-11 %) using microscopic methods, 7% (95 % CI: 4-10%) using coprogantigenic methods and 6% (95 % CI: 4-9%) using molecular diagnostic methods. Molecular methods revealed that dogs were most frequently infected by C. canis (3.64 %) and C. parvum (1.28 %). The pooled prevalence different of subgroups (WHO regions, geographic and climate parameters, diagnostic methods, type of dog) were analyzed separately. The pooled odds ratio (OR) of Cryptosporidium was significantly higher than one for diarrhea status, with dogs suffering from diarrhea having a higher likelihood of Cryptosporidium infection, compared to dogs without diarrhea (OR; 3.61 95 % CI: 1.89-6.90%). The present study is the first systematic review and meta-analysis providing a comprehensive view of the global prevalence of Cryptosporidium in dogs and its related risk factors. Awareness of Cryptosporidium prevalence, risk factors, and disease complications for the health authorities, physicians, veterinarians and dog's owners is important for developing effective strategies to prevent infection.


Assuntos
Criptosporidiose/parasitologia , Doenças do Cão/parasitologia , Animais , Criptosporidiose/complicações , Criptosporidiose/prevenção & controle , Cryptosporidium/fisiologia , Diarreia/etiologia , Doenças do Cão/prevenção & controle , Cães , Saúde Global , Prevalência , Fatores de Risco
8.
AIDS ; 34(3): 469-474, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31714356

RESUMO

OBJECTIVE: Toxoplasma infection remains as the most common cause of focal brain lesions among people living with HIV (PLHIV) despite the decline in opportunistic infections with the introduction of antiretroviral treatment. This study was conducted to provide a summary of evidence about the seroprevalence of Toxoplasma gondii and prevalence of active T. gondii infection and associated risk factors among PLHIV. DESIGN: Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Scopus, PubMed, Science Direct and EMBASE were searched from 1997 to July 2018. All peer-reviewed original research articles describing T. gondii infection among PLHIV with different diagnostic methods were included. METHODS: Incoherence and heterogeneity between studies were quantified by I index and Cochran's Q test. Publication and population bias were assessed with funnel plots and Egger's regression asymmetry test. All statistical analyses were performed using StatsDirect. RESULTS: In total, 111 studies from 37 countries assessing 66 139 blood samples were included in this study. The pooled prevalence of T. gondii infection among PLHIV was 3.24% by IgM and 26.22% by molecular methods using the random-effects model. Pooled seroprevalence of T. gondii by IgG was 44.22%. There was a relationship between Toxoplasma prevalence and sex, raw meat consumption, contact with cat and knowledge about toxoplasmosis. CONCLUSION: High Toxoplasma seroprevalence among PLHIV observed in this study emphasizes the need for implementing screening and prophylaxis tailored to the local context. Owing to the serious and significant clinical manifestations of the parasite in case of reactivation, early identification of seropositivity for initiating prophylaxis among those with a CD4 cell count of less than 200 cells/ml is recommended.


Assuntos
Infecções por HIV , Toxoplasmose , Animais , Anticorpos Antiprotozoários , Gatos , Estudos Transversais , Infecções por HIV/complicações , Humanos , Fatores de Risco , Estudos Soroepidemiológicos , Toxoplasmose/complicações , Toxoplasmose/epidemiologia
9.
Vet Parasitol ; 262: 30-41, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30389009

RESUMO

The aim of this review was to assess our current knowledge on phylogeography and global genetic structure of Echinococcus multilocularis populations originating from rodents, wild canid hosts, and human. Six bibliographic databases were searched from 1990 to 2017, identifying a total of 110 publications. The cytochrome c oxidase subunit 1 (cox1) and cytochrome b (cytb) sequences of E. multilocularis from Asia, Europe, and North Americas were analyzed to estimate the diversity and neutrality indices, and genetic differentiation. A total of 69 (cox1, 36.7%) and 16 haplotypes (cytb, 19.2%) were grouped into various geographical clades. A parsimonious haplotype network demonstrated a star-like feature with haplo-groups Em2 (Asia: 36%), Em105 (Eastern Tibetan plateau: 4.8%), Em46 (Europe: 9.1%), Em73, (Europe: 2.7%) and Em92 (North Americas: 4.3%) as the most common haplotypes. A relatively high level of genetic diversity was detected in rodent-derived E. multilocularis isolates (Haplotype diversity: 0.944), wild canids (Hd: 0.912), and human origin (Hd: 0.704). The highest number of haplotypes (n = 59) and the highest haplotype diversity (0.969) were identified in the Asian and European populations, respectively. Cladistic phylogenetic tree indicated the European clade has a sister relationship with the Asian clade. However, some North American haplotypes were assigned to the European clade together with haplotypes from Poland. The statistically significant Fst values indicated that E. multilocularis populations of Asian-European, Asian-North American, and European-North American origins were genetically differentiated (Fst: 0.22624 to 0.43059). An occurrence of distinct parasite populations suggests that E. multilocularis derived from glacial refugia have been plausibly sustained by indigenous hosts during the Pleistocene Epoch.


Assuntos
Canidae/parasitologia , Equinococose/parasitologia , Echinococcus multilocularis/genética , Variação Genética , Doenças dos Roedores/parasitologia , Animais , Ásia/epidemiologia , Citocromos/genética , Equinococose/epidemiologia , Echinococcus multilocularis/classificação , Echinococcus multilocularis/isolamento & purificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Europa (Continente)/epidemiologia , Genética Populacional , Haplótipos , Proteínas de Helminto/genética , Humanos , Proteínas Mitocondriais/genética , América do Norte/epidemiologia , Filogeografia , Doenças dos Roedores/epidemiologia , Roedores
10.
GMS Hyg Infect Control ; 11: Doc04, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26958458

RESUMO

BACKGROUND: Pseudomonas aeruginosa, as Gram-negative rod bacilli, has an important role in human infection. In the present study we aimed to investigate the presence of exo genes and biofilm production among Pseudomonas aeruginosa isolates in Northwest Iran. MATERIAL AND METHODS: 160 isolates of P. aeruginosa were collected and identified by biochemical tests and were characterized for antibiotic resistance. Biofilm production was evaluated by microtiter plate assay and the presence of exo genes was evaluated by allele-specific PCR (polymerase chain reaction). Chi-square test was used for statistical analysis. RESULTS: The most effective antibiotics against isolates were colistin and polymyxin B. 87% of the isolates were biofilm producers of which 69% were strongly biofilm producers. 55% of the isolates carried exoY, 52% of the isolates carried exoU, and 26.3% and 5% carried exoS and exoT, respectively. CONCLUSION: Our findings showed different distribution of exo genes in clinical isolates of P. aeruginosa in Northwest Iran. ExoS and exoU were more prevalent in non-biofilm producers and exoY was more prevalent in biofilm producer isolates. These results might indicate the importance of exoY in biofilm production of Pseudomonas aeruginosa.

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