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1.
Ann Agric Environ Med ; 26(4): 523-531, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31885223

RESUMO

INTRODUCTION: Over 300 species of parasites can possibly be passed on humans. Most of the parasitic infections are defined based on their pathogenicity; however, some positive effects of a parasite existence within the human body have recently been suggested. Beneficial outcomes of parasite infections might result from the production and release of metabolites, modification of host immune response or products uptake of the host. OBJECTIVE: The aim of the study was a comprehensive analysis of a wide range of effects of parasites on the human body, including an overview of the toxic and positive effects. STATE OF KNOWLEDGE: In the light of the latest research presenting the unconventional use of parasites in medicine, the widely understood of their impact on the human body can also be considered in a positive context. Clinical cases from diseases caused by the toxic effects of parasites, as described in recent years, indicate that the problem of parasitic infections still persists. Despite a great deal of knowledge about the toxic effects of parasites on the human organism and, above all, despite the improvement in sanitary conditions, there is a resurgence of parasitic infections, as evidenced, e.g. by the examples presented in this review. CONCLUSIONS: The examples of positive effects of parasites presented so far give hope for the future in terms of fighting many diseases for which pharmacological treatment has not yet brought a positive effect. A better understanding of those processes might lead to the development of new methods of unconventional medical treatment.


Assuntos
Parasitos/química , Doenças Parasitárias/parasitologia , Animais , Humanos , Medicina , Parasitos/metabolismo , Doenças Parasitárias/imunologia
2.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(5): 555-559, 2019 Jul 24.
Artigo em Chinês | MEDLINE | ID: mdl-31713395

RESUMO

Exosomes are tiny vesicles secreted by most endogenous cells, and the extracellular vesicles (EVs) are specifically secreted by cells. Recently, it was found that exosomes contain a large quantity of important substances such as proteins, nucleic acids, and lipids, which play important roles in material exchange and information transmission in cell-cell communication, and in modulating the immune response, metabolism, and expansion, metastasis, and drug resistance of tumors. This paper summarizes the recent researches on exosomes in parasites and parasitic diseases and hopes to be helpful for improving the researches of parasites and parasitic diseases.


Assuntos
Exossomos , Vesículas Extracelulares , Parasitos , Doenças Parasitárias , Animais , Vesículas Extracelulares/fisiologia , Interações Hospedeiro-Parasita/fisiologia , Parasitos/citologia , Doenças Parasitárias/parasitologia , Pesquisa/tendências
3.
J Biosci ; 44(4)2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31502575

RESUMO

The parasitic nematode Haemonchus contortus is one of the world's most important parasites of small ruminants that causes significant economic losses to the livestock sector. The population structure and selection in its various strains are poorly understood. No study so far compared its different populations using genome-wide data. Here, we focused on different geographic populations of H. contours from China (Tibet, TB; Hubei, HB; Inner Mongolia, IM; Sichuan, SC), UK and Australia (AS), using genome-wide population-genomic approaches, to explore genetic diversity, population structure and selection. We first performed next-generation high-throughput 2b RAD pool sequencing using Illumina technology, and identified single-nucleotide polymorphisms (SNPs) in all the strains. We identified 75,187 SNPs for TB, 82,271 for HB, 82,420 for IM, 79,803 for SC, 83,504 for AS and 78,747 for UK strain. The SNPs revealed low-nucleotide diversity (pi= 0.0092-0.0133) within each strain, and a significant differentiation level (average Fst = 0.34264) among them. Chinese populations TB and SC, along with the UK strain, were more divergent populations. Chinese populations IM and HB showed affinities to the Australian strain. We then analysed signature of selection and detected 44 (UK) and 03 (AS) private selective sweeps containing 49 and 05 genes, respectively. Finally, we performed the functional annotation of selective sweeps and proposed biological significance to signature of selection. Our data suggest that 2b-RAD pool sequencing can be used to assess the signature of selection in H. contortus.


Assuntos
Resistência a Medicamentos/genética , Haemonchus/genética , Doenças Parasitárias/genética , Animais , Austrália/epidemiologia , China/epidemiologia , Variação Genética , Genótipo , Haemonchus/patogenicidade , Sequenciamento de Nucleotídeos em Larga Escala , Mongólia/epidemiologia , Doenças Parasitárias/epidemiologia , Doenças Parasitárias/parasitologia , Polimorfismo de Nucleotídeo Único/genética , Tibet/epidemiologia , Reino Unido/epidemiologia
4.
Bull Soc Pathol Exot ; 112(2): 61-70, 2019.
Artigo em Francês | MEDLINE | ID: mdl-31478617

RESUMO

In order to evaluate the abundance of oocysts in the Mezam watershed in Bamenda, Northwest Region of Cameroon, a study was carried out from January to June 2017. Samples were collected monthly from 13 stations within the watershed. The direct concentration method and the Ziehl-Neelsen technique were employed in the identification of these parasites. The physicochemical analysis showed that the water samples had a neutral pH (7.46±0.46), lowly mineralized (165.61±110.02µS/cm), moderately oxygenated (60.64 ± 17, 25%), present moderate organic pollution (2.85±2.49mg/l KMnO4). KMnO4) and low levels of orthophosphate (1.8±1.88 mg/l PO43-) and nitrates (2.47±5.06 mg/l NO3-). Biological analysis revealed the presence of Cryptosporidium spp. (143.98±203.35 oocysts/l), Isospora belli (88.47 ± 123.19 oocysts/l), Cyclospora cayetanensis (141.31±143.19 oocysts/l) and Sarcocystis hominis (76 ± 111.04 oocysts/l). The highest densities of these parasites were recorded at the Mufueh stream, situated in the periurban area. Meanwhile, the lowest densities were found in the urban area (Formuki, Mankon, Ayaba and Mezam streams). The dry season showed higher densities of oocysts (471.42±216.32 oocysts /l). Statistical analysis revealed a significant correlation (P ≤ 0.05) between the density of the organisms and the physico-chemical parameters such as pH, oxidability, dissolved oxygen and nitrates. Respecting basic hygienic rules as well as treating water before use would reduce the risk of contamination of the population.


Assuntos
Oocistos/isolamento & purificação , Rios/parasitologia , Poluição da Água/análise , Animais , Camarões , Contagem de Células , Cryptosporidium/citologia , Cryptosporidium/isolamento & purificação , Cyclospora/citologia , Cyclospora/isolamento & purificação , Fezes/parasitologia , Humanos , Isospora/citologia , Isospora/isolamento & purificação , Oocistos/citologia , Doenças Parasitárias/parasitologia , Rios/química , Sarcocystis/citologia , Sarcocystis/isolamento & purificação , Poluentes Químicos da Água/análise , Abastecimento de Água
5.
Parasitol Res ; 118(9): 2635-2642, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31363922

RESUMO

The geographical distribution of tuberculosis (TB) overlaps with various parasitic infections. Uncovering the characteristics of coinfecting parasites that potentially affect the host susceptibility to TB is pertinent as it may provide input to current TB therapeutic and prophylactic measures. The present study was aimed at examining the types of parasitic infections in TB patients and healthy TB contacts (HC) in Orang Asli, Malaysian aborigines, who dwelled in the co-endemic areas. Stool and serum samples were collected from Orang Asli who fulfilled the selection criteria and provided written informed consents. Selected parasitic infections in the two study groups were determined by stool examination and commercial serum antibody immunoassays. The prevalence of parasitic infections in TB and HC participants were 100% (n = 82) and 94.6% (n = 55) respectively. The parasitic infections comprised toxocariasis, trichuriasis, amoebiasis, toxoplasmosis, hookworm infection, ascariasis, strongyloidiasis, and brugian filariasis, in decreasing order of prevalence. Overall, helminth or protozoa infection did not show any significant association with the study groups. However, when the species of the parasite was considered, individuals exposed to trichuriasis and toxoplasmosis showed significant odds reduction (odds ratio (OR) 0.338; 95% confidence interval (CI) 0.166, 0.688) and odds increment (OR 2.193; 95% CI 1.051, 4.576) to have active pulmonary TB, respectively. In conclusion, trichuriasis and toxoplasmosis may have distinct negative and positive associations respectively with the increase of host susceptibility to TB.


Assuntos
Parasitos/isolamento & purificação , Doenças Parasitárias/parasitologia , Tuberculose Pulmonar/parasitologia , Adulto , Animais , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/parasitologia , Estudos Transversais , Fezes/parasitologia , Feminino , Humanos , Malásia/epidemiologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Parasitos/classificação , Parasitos/genética , Doenças Parasitárias/epidemiologia , Prevalência , Fatores de Risco , Tuberculose Pulmonar/epidemiologia , Adulto Jovem
6.
BMC Infect Dis ; 19(1): 576, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31272486

RESUMO

BACKGROUND: Pleural parasitic infestation (PPI) is a disease prevalent in certain parts of the world. It is frequently misdiagnosed due to its lack of standardized diagnostic criteria. The purpose of this study was to evaluate the clinical characteristics of PPI patients and develop a practical diagnostic approach for PPI. METHODS: A retrospective study was conducted by reviewing the medical records of 11 patients with PPI. A practical diagnostic approach was proposed based on the unique laboratory findings. RESULTS: All patients demonstrated respiratory symptoms, including shortness of breath, cough, fever, chest pain, excessive sputum and hemoptysis. Leukocytosis (> 10,000/µL) and eosinophilia (> 500/µL) of peripheral blood were present in 45.5 and 36.4% patients, respectively. The mean concentrations of pleural effusion lactate dehydrogenase (LDH), adenosine deaminase (ADA), protein and carcinoembryonic antigen (CEA) were 338.2 U/L (range, 61-667 U/L), 11.6 U/L (range, 0.1-28.2 U/L), 43.7 g/dL (range, 21.9-88.1 g/dL), and 1.84 mg/mL (range, 0.28-4.8 mg/mL), respectively. The mean percentage of eosinophils in the pleural effusion was 19.5% (10.5-41%). Blood test was positive for parasite-specific IgG antibody in 9 patients, including 4 for Paragonimus westermani, 3 for Taenia solium, 1 for Clonorchis sinensis and 1 for Echinococcus granulosus. Eggs of Clonorchis sinensis were detected in the stool of two patients. Sparganum was found in the pleural effusion of one patient. Respiratory symptoms and abnormal appearances in pulmonary radiographic examination were disappeared in all patients who received anti-parasitic treatment. CONCLUSIONS: In patients with unexplained pleural effusion, parasite-specific IgG antibody tests should be performed when pleural fluid testing shows eosinophilic pleural effusion. It is preferable to consider the diagnosis of PPI in clinical practice when serum parasite-specific IgG antibody test is positive.


Assuntos
Imunoglobulina G/análise , Doenças Parasitárias/diagnóstico , Idoso , Dor no Peito , Tosse , Eosinófilos/patologia , Feminino , Febre , Hemoptise , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Parasitárias/parasitologia , Doenças Parasitárias/patologia , Derrame Pleural/metabolismo , Derrame Pleural/parasitologia , Estudos Retrospectivos , Escarro
7.
J Parasitol ; 105(3): 480-483, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31251704

RESUMO

Stool ova and parasite examination using concentration methods remains the gold standard for the investigation of digestive parasitosis. Recently, single-use filtration devices have been marketed for stool concentration sedimentation methods such as MIF or Bailenger, which improve the analytical quality by avoiding contact with feces. In this study, the Parasep® device was adapted to the Faust technique flotation method. In addition, the performance between conventional techniques (MIF concentration and Faust) and techniques using this device was evaluated on 25 formalin-preserved stools and 3 fresh stools. With the Parasep device, the main parasites (protozoa or helminths) were isolated, and the technical requirements such as hygiene control for the operator and realization according to good laboratory practice were improved due to the filtration device.


Assuntos
Fezes/parasitologia , Parasitos/isolamento & purificação , Doenças Parasitárias/diagnóstico , Animais , Blastocystis hominis/isolamento & purificação , Diarreia/parasitologia , Entamoeba/isolamento & purificação , Giardia lamblia/isolamento & purificação , Doenças Parasitárias/parasitologia
8.
Molecules ; 24(7)2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30959737

RESUMO

Guanine-quadruplex (G4) motifs, at both the DNA and RNA levels, have assumed an important place in our understanding of the biology of eukaryotes, bacteria and viruses. However, it is generally little known that their very first description, as well as the foundational work on G4s, was performed on protozoans: unicellular life forms that are often parasitic. In this review, we provide a historical perspective on the discovery of G4s, intertwined with their biological significance across the protozoan kingdom. This is a history in three parts: first, a period of discovery including the first characterisation of a G4 motif at the DNA level in ciliates (environmental protozoa); second, a period less dense in publications concerning protozoa, during which DNA G4s were discovered in both humans and viruses; and third, a period of renewed interest in protozoa, including more mechanistic work in ciliates but also in pathogenic protozoa. This last period has opened an exciting prospect of finding new anti-parasitic drugs to interfere with parasite biology, thus adding new compounds to the therapeutic arsenal.


Assuntos
DNA de Protozoário/genética , Eucariotos/genética , Quadruplex G , Doenças Parasitárias/genética , Animais , Antiparasitários/química , Antiparasitários/uso terapêutico , Eucariotos/efeitos dos fármacos , Humanos , Parasitos/genética , Doenças Parasitárias/tratamento farmacológico , Doenças Parasitárias/parasitologia , RNA/genética , Vírus/genética
9.
Adv Parasitol ; 104: 39-112, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31030771

RESUMO

Humans and animals have co-existed with parasites in a battle of constant adaptation to one another. It is becoming increasingly clear that extracellular vesicles (EVs) play important roles in this co-existence and pathology. This chapter reviews the current research on EVs released by protozoa, nematodes, trematodes, and cestodes with a special focus on EVs in parasite life cycles. The environmental changes experienced by the parasite during its life cycle is associated with distinct changes in EV release and content. The function of these EV seems to have a significant influence on parasite pathology and survival in the host by concomitantly modulating host immune responses and triggering parasite differentiation. The role of EVs in communication between the parasites and the host adds a new level of complexity in our understanding of parasite biology, which may be a key to further understand the complexity behind host-parasite interactions and communication. This increased understanding can, in turn, open up new avenues for vaccine, diagnostic, and therapeutic development for a wide variety of diseases such as parasite infection, cancers, and immunological disorders.


Assuntos
Vesículas Extracelulares/imunologia , Interações Hospedeiro-Parasita , Doenças Parasitárias/imunologia , Animais , Humanos , Doenças Parasitárias/parasitologia
11.
Front Immunol ; 10: 212, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30815000

RESUMO

The study of molecular host-parasite interactions is essential to understand parasitic infection and adaptation within the host system. As well, prevention and treatment of infectious diseases require a clear understanding of the molecular crosstalk between parasites and their hosts. Yet, large-scale experimental identification of host-parasite molecular interactions remains challenging, and the use of computational predictions becomes then necessary. Here, we propose a computational integrative approach to predict host-parasite protein-protein interaction (PPI) networks resulting from the human infection by 15 different eukaryotic parasites. We used an orthology-based approach to transfer high-confidence intraspecies interactions obtained from the STRING database to the corresponding interspecies homolog protein pairs in the host-parasite system. Our approach uses either the parasites predicted secretome and membrane proteins, or only the secretome, depending on whether they are uni- or multi-cellular, respectively, to reduce the number of false predictions. Moreover, the host proteome is filtered for proteins expressed in selected cellular localizations and tissues supporting the parasite growth. We evaluated the inferred interactions by analyzing the enriched biological processes and pathways in the predicted networks and their association with known parasitic invasion and evasion mechanisms. The resulting PPI networks were compared across parasites to identify common mechanisms that may define a global pathogenic hallmark. We also provided a study case focusing on a closer examination of the human-S. mansoni predicted interactome, detecting central proteins that have relevant roles in the human-S. mansoni network, and identifying tissue-specific interactions with key roles in the life cycle of the parasite. The predicted PPI networks can be visualized and downloaded at http://orthohpi.jensenlab.org.


Assuntos
Interações Hospedeiro-Parasita , Parasitos/fisiologia , Doenças Parasitárias/parasitologia , Animais , Biologia Computacional/métodos , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/imunologia , Humanos , Modelos Biológicos , Doenças Parasitárias/genética , Doenças Parasitárias/imunologia , Doenças Parasitárias/metabolismo , Mapeamento de Interação de Proteínas , Proteínas de Protozoários/metabolismo
12.
Molecules ; 24(6)2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30875854

RESUMO

New anti-infective agents are urgently needed to fight microbial resistance. Methicillin-resistant Staphylococcus aureus (MRSA) strains are particularly responsible for complicated pathologies that are difficult to treat due to their virulence and the formation of persistent biofilms forming a complex protecting shell. Parasitic infections caused by Trypanosoma brucei and Leishmania mexicana are also of global concern, because of the mortality due to the low number of safe and effective treatments. Female inflorescences of hop produce specialized metabolites known for their antimicrobial effects but underexploited to fight against drug-resistant microorganisms. In this study, we assessed the antimicrobial potential of phenolic compounds against MRSA clinical isolates, T. brucei and L. mexicana. By fractionation process, we purified the major prenylated chalcones and acylphloroglucinols, which were quantified by UHPLC-UV in different plant parts, showing their higher content in the active flowers extract. Their potent antibacterial action (MIC < 1 µg/mL for the most active compound) was demonstrated against MRSA strains, through kill curves, post-antibiotic effects, anti-biofilm assays and synergy studies with antibiotics. An antiparasitic activity was also shown for some purified compounds, particularly on T. brucei (IC50 < 1 to 11 µg/mL). Their cytotoxic activity was assessed both on cancer and non-cancer human cell lines.


Assuntos
Anti-Infecciosos/química , Produtos Biológicos/química , Humulus/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Biofilmes/efeitos dos fármacos , Produtos Biológicos/farmacologia , Humanos , Leishmania mexicana/efeitos dos fármacos , Leishmania mexicana/patogenicidade , Staphylococcus aureus Resistente à Meticilina/química , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Testes de Sensibilidade Microbiana , Doenças Parasitárias/tratamento farmacológico , Doenças Parasitárias/parasitologia , Trypanosoma brucei brucei/efeitos dos fármacos , Trypanosoma brucei brucei/patogenicidade
14.
Trends Parasitol ; 35(2): 109-118, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30578150

RESUMO

Coinfections by multiple parasites predominate in the wild. Interactions between parasites can be antagonistic, neutral, or facilitative, and they can have significant implications for epidemiology, disease dynamics, and evolution of virulence. Coinfections commonly result from sequential exposure of hosts to different parasites. We argue that the sequential nature of coinfections is important for the consequences of infection in both natural and man-made environments. Coinfections accumulate during host lifespan, determining the structure of the parasite infracommunity. Interactions within the parasite community and their joint effect on the host individual potentially shape evolution of parasite life-history traits and transmission biology. Overall, sequential coinfections have the potential to change evolutionary and epidemiological outcomes of host-parasite interactions widely across plant and animal systems.


Assuntos
Coinfecção/parasitologia , Interações Hospedeiro-Parasita , Doenças Parasitárias/parasitologia , Animais , Humanos , Parasitos/fisiologia , Plantas/parasitologia , Fatores de Tempo
15.
Physiol Biochem Zool ; 92(1): 49-57, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30481116

RESUMO

Tolerance, or the maintenance of host health or fitness at a given parasite burden, has often been studied in evolutionary and medical contexts, particularly with respect to effects on the evolution of parasite virulence and individual patient outcomes. These bodies of work have provided insight about tolerance for evolutionary phenomena (e.g., virulence) and individual health (e.g., recovering from an infection). However, due to the specific motivations of that work, few studies have considered the ecological ramifications of variation in tolerance, namely, how variation in forms of tolerance could mediate parasite movement through populations and even community-level disease dynamics. Tolerance is most commonly regarded as the relationship between host fitness and parasite burden. However, few if any studies have actually quantified host fitness, instead utilizing proxies of fitness as the response variables to be regressed against parasite burden. Here, we address how attention to the effects of parasite burden on traits that are relevant to host competence (i.e., the ability to amplify parasites to levels transmissible to other hosts/vectors) will enhance our understanding of disease dynamics in nature. We also provide several forms of guidance for how to overcome the challenges of quantifying tolerance in wild organisms.


Assuntos
Interações Hospedeiro-Parasita , Doenças Parasitárias/transmissão , Adaptação Biológica , Animais , Resistência à Doença , Carga Parasitária , Parasitos/patogenicidade , Parasitos/fisiologia , Doenças Parasitárias/parasitologia , Doenças Parasitárias/fisiopatologia
16.
Parasite Immunol ; 41(6): e12588, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30188574

RESUMO

Brazil is a middle-income country undergoing the epidemiological transition. Effects of changes in daily life habits and access to clean water, sanitation and urban services on a growing urban population have contributed to a double burden of both infectious and noncommunicable chronic diseases. Studies have indicated that parasite infections may modulate the human immune system and influence the development of allergic conditions such as asthma. However, there is no consensus in the published literature on the effects of parasitic infections on allergy, perhaps as a consequence of factors determining the epidemiology of these infections that vary between populations such as age of first infection, duration and chronicity of infections, parasite burden and species, and host genetic susceptibility. In this review, we discuss the observations from Brazil concerning the relationship between parasite infections and allergy.


Assuntos
Hipersensibilidade/imunologia , Parasitos/imunologia , Doenças Parasitárias/imunologia , Animais , Brasil , Humanos , Hipersensibilidade/parasitologia , Estudos Observacionais como Assunto , Doenças Parasitárias/parasitologia
17.
Rev Assoc Med Bras (1992) ; 64(12): 1081-1084, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30569983

RESUMO

OBJECTIVE: Halzoun syndrome, also known as nasopharyngeal linguatulosis, is a rare entity that is mostly prevalent in Eastern Mediterranean countries. The consumption of raw ovine liver and lymph nodes infested with Linguatula serrata nymphs remains a major cause of the nasopharyngeal symptoms and discomfort associated with the disease. Halzoun syndrome is a clinical diagnosis based on history and presentation. METHODS: Treatment of this disease is still debated; however, our experience reveals that alcohol gargle can be a good option. Proper counselling on the hazards of eating raw liver in endemic areas is needed. RESULTS: Moreover, physicians should be aware of the sequence of events in the disease in order not to delay or miss the diagnosis. CONCLUSIONS: This communication presents a rare Lebanese case of Halzoun syndrome that offers medical implications in the clinical diagnosis and treatment of the nasopharyngeal symptoms of this syndrome, with a review of the literature.


Assuntos
Doenças Transmitidas por Alimentos/parasitologia , Nasofaringite/parasitologia , Doenças Parasitárias/parasitologia , Pentastomídeos , Animais , Feminino , Doenças Transmitidas por Alimentos/diagnóstico , Doenças Transmitidas por Alimentos/tratamento farmacológico , Humanos , Nasofaringite/diagnóstico , Nasofaringite/tratamento farmacológico , Doenças Parasitárias/diagnóstico , Doenças Parasitárias/tratamento farmacológico , Adulto Jovem
18.
Artigo em Inglês | MEDLINE | ID: mdl-30425970

RESUMO

Parasitic infections like amebiasis, trichomoniasis, and giardiasis are major health threats in tropical and subtropical regions of the world. Metronidazole (MTZ) is the current drug of choice for amebiasis, giardiasis, and trichomoniasis but it has several adverse effects and potential resistance is a concern. In order to develop alternative antimicrobials, a library of 1H-1,2,3-triazole-tethered metronidazole-isatin conjugates was synthesized using Huisgen's azide-alkyne cycloaddition reaction and evaluated for their amebicidal, anti-trichomonal, and anti-giardial potential. Most of the synthesized conjugates exhibited activities against Trichomonas vaginalis, Tritrichomonas foetus, Entamoeba histolytica, and Giardia lamblia. While activities against T. vaginalis and T. foetus were comparable to that of the standard drug MTZ, better activities were observed against E. histolytica and G. lamblia. Conjugates 9d and 10a were found to be 2-3-folds more potent than MTZ against E. histolytica and 8-16-folds more potent than MTZ against G. lamblia. Further analysis of these compounds on fungi and bacteria did not show inhibitory activity, demonstrating their specific anti-protozoal properties.


Assuntos
Antiprotozoários/farmacologia , Doenças Transmitidas por Alimentos/parasitologia , Isatina/farmacologia , Metronidazol/farmacologia , Doenças Parasitárias/parasitologia , Doenças Sexualmente Transmissíveis/parasitologia , Triazóis/farmacologia , Anaerobiose , Antiprotozoários/síntese química , Entamoeba histolytica/efeitos dos fármacos , Giardia lamblia/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Isatina/síntese química , Metronidazol/síntese química , Testes de Sensibilidade Parasitária , Triazóis/síntese química , Trichomonas vaginalis/efeitos dos fármacos , Tritrichomonas foetus/efeitos dos fármacos
19.
PLoS Negl Trop Dis ; 12(11): e0006794, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30418968

RESUMO

Progress towards controlling and eliminating parasitic worms, including schistosomiasis, onchocerciasis, and lymphatic filariasis, is advancing rapidly as national governments, multinational NGOs, and pharmaceutical companies launch collaborative chemotherapeutic control campaigns. Critical questions remain regarding the potential for achieving elimination of these infections, and analytical methods can help to quickly estimate progress towards-and the probability of achieving-elimination over specific timeframes. Here, we propose the effective reproduction number, Reff, as a proxy of elimination potential for sexually reproducing worms that are subject to poor mating success at very low abundance (positive density dependence, or Allee effects). Reff is the number of parasites produced by a single reproductive parasite at a given stage in the transmission cycle, over the parasite's lifetime-it is the generalized form of the more familiar basic reproduction number, R0, which only applies at the beginning of an epidemic-and it can be estimated in a 'model-free' manner by an estimator ('ε'). We introduce ε, demonstrate its estimation using simulated data, and discuss how it may be used in planning and evaluation of ongoing elimination efforts for a range of parasitic diseases.


Assuntos
Erradicação de Doenças/métodos , Administração Massiva de Medicamentos/estatística & dados numéricos , Schistosoma/efeitos dos fármacos , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Animais , Número Básico de Reprodução , Coleta de Dados , Erradicação de Doenças/estatística & dados numéricos , Métodos Epidemiológicos , Humanos , Administração Massiva de Medicamentos/métodos , Modelos Teóricos , Oncocercose/tratamento farmacológico , Parasitos/fisiologia , Doenças Parasitárias/tratamento farmacológico , Doenças Parasitárias/epidemiologia , Doenças Parasitárias/parasitologia , Reprodução , Schistosoma/fisiologia , Esquistossomose/tratamento farmacológico , Esquistossomose/transmissão
20.
Nutr Hosp ; 35(5): 1145-1152, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30307299

RESUMO

INTRODUCTION: it has previously been shown that parasitic infections (PI) have deleterious effects on the nutritional status of the host, particularly among young children. OBJECTIVE: the objective of this study was to estimate the severity of the problem of malnutrition and anemia in association with PI in preschool children and to identify the possible risk factors that contribute to these health problems. METHODS: four hundred and thirty-seven mother-child pairs were randomly selected from rural areas of Peshawar, Pakistan. Children with visible and invisible worms were identified. The nutritional status of the respondents was evaluated. Structured questionnaires were used to collect data on relevant parameters. Appropriate statistical tests were used to analyze the data. RESULTS: the average age of the children was 24 ± 10 months. A total of 120 (27.5%) fecal samples of children tested positive for several parasites. Of the total, 267 (61%), 205 (47%), 109 (25%) and 140 (32%) children were anemic, stunted, wasted and underweight, respectively. The majority of wasted children (59% wasted versus 41% normal) and anemic (66% anemic versus 34% non-anemic) were infected with parasites (p < 0.05). Independent factors related to child anemia included child age, family size, mothers' awareness of overall child healthcare, and PIs. PIs were independent risk factors for malnutrition and general child wasting. Sociodemographic, parental and child-related risk factors for PIs included mothers' poor nutritional status and awareness level regarding overall child healthcare, fathers' formal education, child's pica habit, child's age, open sewage system in the houses and family size. CONCLUSION: in general, malnutrition and anemia were highly prevalent in children in association with PI.


Assuntos
Anemia/epidemiologia , Desnutrição/epidemiologia , Doenças Parasitárias/epidemiologia , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Desnutrição/parasitologia , Estado Nutricional , Paquistão/epidemiologia , Doenças Parasitárias/parasitologia , Prevalência , Fatores de Risco , População Rural
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