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1.
Pathogens ; 12(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37513737

RESUMO

Infection with Leishmania amazonensis and L. mexicana may lead to diffuse cutaneous leishmaniasis. The cure is exceptional, especially for the strange case of this lady. Case report: The patient acquired the disease in childhood and remained with lesions for over 30 years, albeit several treatments. She worsened after a pregnancy, developing disseminated lesions. Miltefosine with amphotericin B and pentamidine resulted in remission. Lesions reappeared after one year, accompanied by intra-nasal infiltration of the disease. The nasal spraying of a single ampoule of pentavalent antimoniate resulted in the sustained disappearance of the nasal symptoms and all the cutaneous lesions. After over eight years, she remains disease-free, albeit under renal replacement therapy. The high nasal mucosal antimonial concentration may explain the long-lasting cure via new MHC class I epitope-specific CD8+ cell clones against L. amazonensis present in the nasal mucosa.

2.
An Acad Bras Cienc ; 92(2): e20190388, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32638870

RESUMO

Extreme climatic events and their hazards have strong impact on society. Urban areas in Brazil are especially vulnerable to the impact of such events due to their rapid growth and inappropriate infrastructure. Viçosa is a mid-sized city in Southeastern Brazil that has been experiencing issues associated with urban expansion and population growth since the 1960s. Thus, this study aims to identify patterns of extreme climate events in Viçosa based on daily temperature and precipitation time series (1968-2017). Homogeneity tests were carried out in order to identify breaking points in these climate variables. Climate trends were analyzed through Mann-Kendall test and their magnitude was checked based on Sen's slope. Results have evidenced statistically significant and increasing trends in annual minimum temperature since the 1990s. Moreover, statistically significant breaking points in extreme temperature indices have shown increasing number of warm days, and decreasing number of cold nights, in both annual and seasonal analyses. Extreme climatic events have been observed more often in recent years, mainly in the number of consecutive dry days and maximum and heavy precipitation days. Based on results, Viçosa experiences warmer conditions throughout the year, whereas more (less) torrential rainfall events have been occurring during Summer (Winter).


Assuntos
Temperatura , Brasil , Cidades , Estações do Ano
3.
Sci Rep ; 10(1): 10543, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601369

RESUMO

Tegumentary leishmaniasis (TL) is a parasitic disease that can result in wide spectrum clinical manifestations. It is necessary to understand host and parasite determinants of clinical outcomes to identify novel therapeutic targets. Previous studies have indicated that the polyamine biosynthetic pathway is critical for Leishmania growth and survival. Despite its importance, expression of the such pathway has not been previously investigated in TL patients. We performed an exploratory analysis employing Systems Biology tools to compare circulating polyamines and amino acid concentration as well as polyamine pathway gene expression in cutaneous lesions patients presenting with distinct TL disease presentations. Diffuse cutaneous leishmaniasis (DCL) was associated with higher concentrations of amino acids, polyamines and its substrate transporters than mucosal cutaneous leishmaniasis or localized cutaneous leishmaniasis. In addition, the RNA expression of polyamine-related genes of patients lesions from two separate cohorts demonstrated that differential activation of this pathway is associated with parasite loads and able to discriminate the clinical spectrum of TL. Taken together, our findings highlight a new aspect of DCL immunopathogenesis indicating that the polyamine pathway may be explored as a novel therapeutic target to control disease burden.


Assuntos
Aminoácidos/metabolismo , Vias Biossintéticas/fisiologia , Leishmaniose Tegumentar Difusa/metabolismo , Poliaminas/metabolismo , Pele/metabolismo , Adulto , Aminoácidos/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Mucosa/metabolismo , Poliaminas/sangue
4.
Diagn Microbiol Infect Dis ; 91(4): 312-318, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29653798

RESUMO

Hsp70 is a cytoplasmic heat-shock protein, encoded by a multicopy tandemly repeated gene that has recently been gaining popularity as a valuable marker for typing Leishmania species. In this study, we used a previously described hsp70 PCR-RFLP method for identifying Brazilian Leishmania isolates. We identified two distinct L. (L.) amazonensis hsp70 alleles that resulted in two different RFLP patterns. Also, we found RFLP polymorphisms amongst L. (Viannia) naiffi strains. The profiles of both L. (V.) shawi and L. (V.) lindenbergi were very similar to those of other L. (Viannia) species. The observations described herein reflect the polymorphism found within species of Leishmania and indicate that results from this hsp70 PCR-RFLP method should be used with caution when typing isolates from clinical cases of leishmaniasis and Leishmania species from Brazil.


Assuntos
Proteínas de Choque Térmico HSP70/genética , Leishmania/genética , Leishmaniose Cutânea/parasitologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição/genética , Proteínas de Protozoários/genética , Alelos , Animais , Brasil , DNA de Protozoário/genética , Genoma de Protozoário/genética , Humanos , Leishmania/classificação , Leishmania braziliensis/genética , Leishmaniose Cutânea/diagnóstico , Filogenia , Análise de Sequência de DNA
5.
J Appl Microbiol ; 124(3): 810-820, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29327477

RESUMO

AIMS: Nitrogen is a critical element in industrial fermentation media. This study investigated the influence of various nitrogen sources on blastospore production, desiccation tolerance and storage stability using two strains of the cosmopolitan insect-pathogenic fungus Beauveria bassiana. METHODS AND RESULTS: Complex organic sources of nitrogen such as soy flour, autolysed yeast and cottonseed flour induced great numbers of blastospores after 2-3 days of fermentation, which also survived drying and remained viable (32-56% survival) after 9 months storage at 4°C, although variations were found between strains. Nitrogen availability in the form of free amino acids directly influenced blastospore production and resistance to desiccation. Increasing glucose and nitrogen concentrations up to 120 and 30 g l-1 , respectively, did not improve blastospore production but enhanced desiccation tolerance. Cell viability after drying and upon fast-rehydration was increased when ≥25 g acid-hydrolysed casein per litre was supplemented in the liquid culture medium. CONCLUSIONS: These findings indicate that low-cost complex nitrogen compounds are suitable to enhance yeast-like growth by B. bassiana with good desiccation tolerance and therefore support its further scale-up production as a mycoinsecticide. SIGNIFICANCE AND IMPACT OF THE STUDY: Nitrogen is the most expensive nutrient in liquid media composition, but this study underscores the feasibility of using low-cost nitrogen compounds composed mainly of agro-industrial by-products for rapid production of desiccation-tolerant B. bassiana blastospores by liquid culture fermentation.


Assuntos
Beauveria/metabolismo , Nitrogênio/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento , Beauveria/química , Beauveria/crescimento & desenvolvimento , Meios de Cultura/química , Meios de Cultura/metabolismo , Dessecação , Fermentação , Glucose/metabolismo , Preservação Biológica , Esporos Fúngicos/química , Esporos Fúngicos/metabolismo , Água/análise , Água/metabolismo
6.
Biotechnol Bioeng ; 114(10): 2211-2221, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28627711

RESUMO

Alcoholic fermentation of released sugars in pretreatment and enzymatic hydrolysis of biomass is a central feature for second generation ethanol (E2G) production. Saccharomyces cerevisiae used industrially in the production of first generation ethanol (E1G) convert sucrose, fructose, and glucose into ethanol. However, these yeasts have no ability to ferment pentose (xylose). Therefore, the present work has focused on E2G production by Scheffersomyces stipitis and Spathaspora passalidarum. The fermentation strategy with high pitch, cell recycle, fed-batch mode, and temperature decrease for each batch were performed in a hydrolyzate obtained from a pretreatment at 130°C with NaOH solution (1.5% w/v) added with 0.15% (w/w) of anthraquinone (AQ) and followed by enzymatic hydrolysis. The process strategy has increased volumetric productivity from 0.35 to 0.38 g · L-1 · h-1 (first to third batch) for S. stipitis and from 0.38 to 0.81 g · L-1 · h-1 for S. passalidarum (first to fourth batch). Mass balance for the process proposed in this work showed the production of 177.33 kg ethanol/ton of sugar cane bagasse for S. passalidarum compared to 124.13 kg ethanol/ton of sugar cane bagasse for S. stipitis fermentation. The strategy proposed in this work can be considered as a promising strategy in the production of second generation ethanol. Biotechnol. Bioeng. 2017;114: 2211-2221. © 2017 Wiley Periodicals, Inc.


Assuntos
Ascomicetos/fisiologia , Técnicas de Cultura Celular por Lotes/instrumentação , Reatores Biológicos/microbiologia , Celulose/metabolismo , Etanol/metabolismo , Saccharum/microbiologia , Ascomicetos/classificação , Técnicas de Cultura Celular por Lotes/métodos , Proliferação de Células/fisiologia , Técnicas de Cocultura/instrumentação , Técnicas de Cocultura/métodos , Simulação por Computador , Etanol/isolamento & purificação , Fermentação/fisiologia , Hidrólise , Modelos Biológicos , Especificidade da Espécie , Temperatura
7.
Sci Rep ; 7: 46363, 2017 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-28393908

RESUMO

Previous studies have indicated that the balance between different eicosanoids reflect the intensity of the inflammatory profile in patients with tegumentary leishmaniasis. More recently, pro-resolution lipid mediators have been shown to play critical roles in dampening pathological inflammatory processes to reestablish homeostasis in a diverse range of experimental settings. Among these lipid mediator, resolvins from D series have been described as potent anti-inflammatory and immunomodulatory mediators, and its activities include inhibition of leukocyte chemotaxis and blockage production of proinflammatory cytokines, while increasing the expression of regulatory mediators. Whether resolvins play significant roles in establishment and persistence of Leishmania infection is currently unknown. We addressed this question in the current study by assessing circulating levels of D-series resolvins in tegumentary leishmaniasis patients presenting with localized or diffuse disease. We found heightened expression of resolvin D1 in diffuse cutaneous leishmaniasis which was correlated with expression profile of biomarkers associated with disease pathogenesis. Additional in vitro experiments using primary human macrophages indicated that resolvin D1 may promote intracellular Leishmania amazonensis replication through a mechanism associated with induction of heme oxygenase-1. These results suggest that targeting resolvin D1 could serve as potential strategy for host directed therapy in diffuse cutaneous leishmaniasis.


Assuntos
Ácidos Docosa-Hexaenoicos/sangue , Leishmaniose/sangue , Macrófagos/parasitologia , Adolescente , Adulto , Biomarcadores/metabolismo , Criança , Feminino , Humanos , Leishmania , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
J Helminthol ; 91(6): 686-695, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27866481

RESUMO

Entomopathogenic nematodes (EPNs) of the families Steinernematidae and Heterorhabditidae have a symbiotic association with bacteria which makes them virulent against insects. EPNs have been mass produced using in vivo and in vitro methods, including both solid and liquid fermentation. This study assessed the effect of nematode inoculum age on the production of Steinernema feltiae in liquid, solid and biphasic processes. Several physical parameters were also assessed: the effect of medium viscosity, flask size and aeration speed on the recovery and yield of infective juveniles (IJs). Inoculum age treatments included inoculum liquid cultures that were 7, 14, 21 and 28 days old. Nematodes from the same inoculum were added to one liquid medium (liquid culture), one solid medium with bacteria previously grown in sponge (solid culture) and a variation of the solid medium (a biphasic culture), in which the bacteria were first grown in liquid and, then, soaked into the sponges, with the purpose of providing a more homogeneous bacterial culture before nematode inoculation. Experiments were conducted in Erlenmeyer flasks. Eight treatments were established involving combinations of three variables: two media (with and without 0.2% agar), two flask sizes (250 and 150 ml) and two agitation speeds (180 and 280 rpm). The study showed increases in nematode yield for liquid cultures, but not for solid or biphasic cultures, with the advance of the inoculum age up to 28 days of growth. Furthermore, the addition of 0.2% agar to the liquid medium and increasing the aeration rate by using larger flasks with higher agitation speed may increase nematode recovery and final yield. The experiments were conducted using shake flasks but the results may also be applicable for bioreactors.


Assuntos
Insetos/parasitologia , Rabditídios/crescimento & desenvolvimento , Animais , Meios de Cultura/química , Meios de Cultura/metabolismo , Rabditídios/metabolismo , Rabditídios/microbiologia , Xenorhabdus/crescimento & desenvolvimento , Xenorhabdus/metabolismo , Xenorhabdus/fisiologia
9.
Mem Inst Oswaldo Cruz ; 111(4): 241-51, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27074253

RESUMO

Localised cutaneous leishmaniasis (LCL) is the most common form of cutaneous leishmaniasis characterised by single or multiple painless chronic ulcers, which commonly presents with secondary bacterial infection. Previous culture-based studies have found staphylococci, streptococci, and opportunistic pathogenic bacteria in LCL lesions, but there have been no comparisons to normal skin. In addition, this approach has strong bias for determining bacterial composition. The present study tested the hypothesis that bacterial communities in LCL lesions differ from those found on healthy skin (HS). Using a high throughput amplicon sequencing approach, which allows for better populational evaluation due to greater depth coverage and the Quantitative Insights Into Microbial Ecology pipeline, we compared the microbiological signature of LCL lesions with that of contralateral HS from the same individuals.Streptococcus, Staphylococcus,Fusobacterium and other strict or facultative anaerobic bacteria composed the LCL microbiome. Aerobic and facultative anaerobic bacteria found in HS, including environmental bacteria, were significantly decreased in LCL lesions (p < 0.01). This paper presents the first comprehensive microbiome identification from LCL lesions with next generation sequence methodology and shows a marked reduction of bacterial diversity in the lesions.


Assuntos
Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Leishmaniose Cutânea/microbiologia , Pele/microbiologia , Adulto , Feminino , Bactérias Gram-Negativas/classificação , Bactérias Gram-Positivas/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Pele/parasitologia , Adulto Jovem
10.
Int J Parasitol ; 46(5-6): 343-50, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26953255

RESUMO

Repeated treatments with praziquantel reduce schistosomiasis prevalence and morbidity, but transmission persists and populations often recover within a few years. To identify factors associated with persistence, we surveyed and treated all identified Schistosoma mansoni infections in two rural Brazilian communities (Jenipapo and Volta do Rio) in 2009, 2012 and 2013. Eggs were collected from all infected individuals and genotyped with 11 microsatellite markers to evaluate parasite differentiation and diversity. After successive rounds of community-wide treatment, prevalence decreased from 45% to 24% then 16%. Intensity of infection decreased by 57% over this period, and the number of eggs transmitted to the environment decreased by 92%. During all time periods the majority of eggs were excreted by those >15years of age. The incidence was 23% in 2012 and 15% in 2013, consistent with a decrease in transmission. There was little immigration or gene flow over a distance of 6km. On reinfection, infrapopulations were moderately differentiated indicating that pretreatment multilocus genotypes were not fully reacquired. The effective population size responded to census population decline more rapidly than differentiation. Reinfection was concentrated in the downstream portion of Jenipapo, consistent with the observed increased human fecal contamination. At this scale and in this area S. mansoni infections exist on a fragmented landscape with a highly focal pattern of transmission that may facilitate future elimination.


Assuntos
Anti-Helmínticos/administração & dosagem , Praziquantel/administração & dosagem , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Brasil/epidemiologia , Criança , Pré-Escolar , Fezes/parasitologia , Feminino , Frequência do Gene , Técnicas de Genotipagem , Humanos , Incidência , Lactente , Estudos Longitudinais , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , Praziquantel/farmacologia , Praziquantel/uso terapêutico , Prevalência , Fatores de Risco , População Rural , Schistosoma mansoni/classificação , Schistosoma mansoni/genética , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/transmissão , Adulto Jovem
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