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1.
BMC Infect Dis ; 20(1): 645, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873242

RESUMO

BACKGROUND: During the outbreak of cutaneous leishmaniasis in the Kurdistan Region of Iraq that started in 2015, the course of the disease and the treatment were not consistent with the available literature. Physicians, particularly dermatologists, faced challenges with treating the cutaneous leishmaniasis lesions with high rates of treatment failure and resistance to treatment. We used Q-methodology to understand the range and diversities of opinions and the practical experiences of dermatologists about the treatment difficulties of cutaneous leishmaniasis. METHODS: This Q-methodology study was carried out in Erbil, Kurdistan Region of Iraq, and involved 37 dermatologists. A set of 40 statements related to different aspects of difficulties and uncertainties of treating cutaneous leishmaniasis was prepared. The dermatologists were requested to distribute the 40 statements into a scaled grid of nine piles from least agree to most agree. We applied by-person factor analysis using PQMethod 2.35 for the data analysis. RESULTS: The analysis revealed two different viewpoints about the treatment of cutaneous leishmaniasis and a consensus viewpoint. The first viewpoint emphasized the use of sodium stibogluconate-based combination therapy, concerns with treatment failure, and lack of compliance with the treatment. The second viewpoint emphasized the lack of standard treatment and advances in the treatment of cutaneous leishmaniasis. There was a consensus between both groups of respondents about many aspects of the treatment of cutaneous leishmaniasis, including considering sodium stibogluconate the first drug of choice for cutaneous leishmaniasis treatment. CONCLUSIONS: This study revealed a diversity of viewpoints and uncertainties about the effectiveness of the available treatment modalities and treatment difficulties and failure. Interrupted supply and poor quality of the available drugs and lack of a standard and advanced treatment are the main problems facing the treatment of cutaneous leishmaniasis. More research is required to determine the best treatment modalities for the different types of cutaneous leishmaniasis. There is a need for the development of treatment guidelines specific to the Iraqi context with a particular focus on the treatment of the resistant and atypical cases of cutaneous leishmaniasis.


Assuntos
Gluconato de Antimônio e Sódio/uso terapêutico , Atitude , Consenso , Dermatologistas/psicologia , Leishmania , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/epidemiologia , Adulto , Terapia Combinada , Análise Fatorial , Feminino , Humanos , Incidência , Iraque/epidemiologia , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Falha de Tratamento
2.
Mikrobiyol Bul ; 54(3): 429-443, 2020 Jul.
Artigo em Turco | MEDLINE | ID: mdl-32755519

RESUMO

Although asexual reproduction has been attributed to Leishmania species, genetic exchange has recently been demonstrated, which helped emerging of hybrid isolates. Situated on the crossroads between three continents, Leishmania hybrids may be present in Turkey. In Turkey, visceral leishmaniasis caused by Leishmania infantum is less common, while cutaneous leishmaniasis (CL) caused by Leishmania tropica and L.infantum could reach 2500 reported cases a year. Our aim was to investigate genetic variability of local Leishmania species and presence of hybrid Leishmania strains in Turkey. Twenty CL patients from Sanliurfa and Hatay, where only L.tropica and both L.tropica and L.infantum cause CL, respectively, were registered equally. All isolates were assessed with real-time polymerase chain reaction (Rt-PCR), isoenzyme analysis, gene sequencing, two-dimensional gel electrophoresis (2D-PAGE) and MALDI-TOF/TOFMS followed by in vivo analyses on mouse model. Identification of differentially expressed proteins was performed. These proteins were confirmed by sequence analysis. All isolates from Sanliurfa were found to be L.tropica which caused cutaneous infection in mice. However, one of 10 isolates from Hatay was found as Leishmania major which caused cutaneous infection. Five isolates were found as L.tropica with Rt-PCR and gene sequencing, one of which had one different protein from the reference L.tropica strain and caused cutaneous infection. Four of the five isolates had five different proteins compared to reference strain and caused both cutaneous and visceral infections. Remaining four isolates showed double melting curves in Rt-PCR, which were concordant with L.tropica and L.infantum. Their sequencing and isoenzyme analyses indicated them as L.infantum. They had six different proteins compared to reference L.infantum strain and caused cutaneous and visceral infections. It is concluded that the isolates with different proteins were hybrid Leishmania species. In the present study, outcomes of the proteomics, genomics, clinical manifestations and tissue tropism on animal models were evaluated together for the first time. In addition to L.tropica and L.infantum, L.major was identified as a causative agent for CL and hybrids of L.infantum/tropica were also shown to be present.


Assuntos
Variação Genética , Leishmania , Leishmaniose Cutânea , Leishmaniose Visceral , Animais , Modelos Animais de Doenças , Humanos , Leishmania/genética , Leishmaniose Cutânea/parasitologia , Leishmaniose Visceral/parasitologia , Camundongos , Turquia
3.
PLoS Negl Trop Dis ; 14(8): e0008509, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32804927

RESUMO

Leishmania species are responsible for a broad spectrum of diseases, denominated Leishmaniasis, affecting over 12 million people worldwide. During the last decade, there have been impressive efforts for sequencing the genome of most of the pathogenic Leishmania spp. as well as hundreds of strains, but large-scale proteomics analyses did not follow these achievements and the Leishmania proteome remained mostly uncharacterized. Here, we report a comprehensive comparative study of the proteomes of strains representing L. braziliensis, L. panamensis and L. guyanensis species. Proteins extracted by SDS-mediated lysis were processed following the multi-enzyme digestion-filter aided sample preparation (FASP) procedure and analysed by high accuracy mass spectrometry. "Total Protein Approach" and "Proteomic Ruler" were applied for absolute quantification of proteins. Principal component analysis demonstrated very high reproducibility among biological replicates and a very clear differentiation of the three species. Our dataset comprises near 7000 proteins, representing the most complete Leishmania proteome yet known, and provides a comprehensive quantitative picture of the proteomes of the three species in terms of protein concentration and copy numbers. Analysis of the abundance of proteins from the major energy metabolic processes allow us to highlight remarkably differences among the species and suggest that these parasites depend on distinct energy substrates to obtain ATP. Whereas L. braziliensis relies the more on glycolysis, L. panamensis and L. guyanensis seem to depend mainly on mitochondrial respiration. These results were confirmed by biochemical assays showing opposite profiles for glucose uptake and O2 consumption in these species. In addition, we provide quantitative data about different membrane proteins, transporters, and lipids, all of which contribute for significant species-specific differences and provide rich substrate for explore new molecules for diagnosing purposes. Data are available via ProteomeXchange with identifier PXD017696.


Assuntos
Leishmania/metabolismo , Proteínas de Protozoários/metabolismo , Regulação da Expressão Gênica/fisiologia , Glucose/metabolismo , Leishmania/genética , Consumo de Oxigênio , Proteômica , Proteínas de Protozoários/genética , Especificidade da Espécie
4.
PLoS Negl Trop Dis ; 14(8): e0008380, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797078

RESUMO

In French Guiana, five species are associated with Cutaneous Leishmaniasis (CL). Though infections with Leishmania guyanensis, L. (V.) braziliensis and L. (L.) amazonensis have been extensively described, there are few available clinical and genetic data on L. (V.) lainsoni and L. (V.) naiffi. We determined the clinical and epidemiological features of all cases of CL due to L. (V.) naiffi and L. (V.) lainsoni diagnosed in French Guiana between 2003 and 2019. Phylogenetic analysis was performed by sequencing a portion of HSP70 and cyt b genes. Five cases of L. naiffi and 25 cases of L. lainsoni were reported. Patients infected by L. (V.) lainsoni were usually infected on gold camps, mostly along the Maroni river (60%), while L. naiffi was observed in French patients infected on the coast (100%). A high number of pediatric cases (n = 5; 20%) was observed for L. (V.) lainsoni. A mild clinical course was observed for all cases of L. (V.) naiffi. HSP70 and cyt b partial nucleotide sequence analysis revealed different geographical clusters within L. (V.) naiffi and L. (V.) lainsoni but no association were found between phylogenetic and clinical features. Our data suggest distinct socio-epidemiological features for these two Leishmania species. Patients seem to get infected with L. (V.) naiffi during leisure activities in anthropized coastal areas, while L. (V.) lainsoni shares common features with L. (V.) guyanensis and braziliensis and seems to be acquired during professional activities in primary forest regions. Phylogenetic analysis has provided information on the intraspecific genetic variability of L. (V.) naiffi and L. (V.) lainsoni and how these genotypes are distributed at the geographic level.


Assuntos
Leishmania/classificação , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Citocromos b/genética , Feminino , Guiana Francesa/epidemiologia , Proteínas de Choque Térmico HSP70/genética , Humanos , Lactente , Leishmania/genética , Leishmania/patogenicidade , Leishmaniose Cutânea/patologia , Atividades de Lazer , Masculino , Pessoa de Meia-Idade , Mineração , Doenças Negligenciadas , Filogenia , Estudos Retrospectivos , Análise de Sequência de DNA
5.
Mem Inst Oswaldo Cruz ; 115: e200067, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667458

RESUMO

BACKGROUND Unfortunately, no any vaccine against leishmaniasis has been developed for human use. Therefore, a vaccine based on total Leishmania antigens could be a good and economic approach; and there are different methodologies to obtain these antigens. However, it is unknown whether the method to obtain the antigens affects the integrity and immune response caused by them. OBJECTIVES to compare the protein profile and immune response generated by total L. amazonensis antigens (TLA) produced by different methods, as well as to analyse the immune response and protection by a first-generation vaccine formulated with sonicated TLA (sTLA) and polyinosinic:polycytidylic acid [Poly (I:C)]. METHODS TLA were obtained by four different methodologies and their integrity and immune response were evaluated. Finally, sTLA was formulated with Poly (I:C) and their protective immune response was measured. FINDINGS sTLA presented a conserved protein profile and induced a strong immune response. In addition, Poly (I:C) improved the immune response generated by sTLA. Finally, sTLA + Poly (I:C) formulation provided partial protection against L. amazonensis infection. MAIN CONCLUSIONS The protein profile and immune response depend on the methodology used to obtain the antigens. Also, the formulation sTLA + Poly (I:C) provides partial protection against cutaneous leishmaniasis in mice.


Assuntos
Leishmania , Vacinas contra Leishmaniose , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/prevenção & controle , Vacinas Protozoárias/imunologia , Receptor 3 Toll-Like/imunologia , Animais , Antígenos de Protozoários/imunologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C
6.
Clin Dermatol ; 38(2): 140-151, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32513395

RESUMO

Cutaneous leishmaniasis (CL) is called "the great imitator," because it can mimic almost all types of dermatoses. This similarity may sometimes lead to misdiagnosis, resulting in inappropriate treatment and morbidities. Atypical forms occur due to the interaction between parasitic factors and the host immune response. Secondary infection or mistreatment of CL can also alter the natural course, resulting in bizarre and misdiagnosed cases. Atypical leishmaniasis should be considered in longstanding and painless lesions that may simulate erysipelas, dermatitis, verruca, herpes zoster, paronychia, and sporotrichosis. Less commonly, sarcoidosis, deep mycosis, basal and squamous cell carcinoma, cutaneous lymphoma, or pseudolymphomalike lesions may need to be considered in the differential diagnosis. A high index of suspicion is required to consider a diagnosis of CL, especially in nonendemic or newly endemic regions. Smear, histopathologic examination, culture, and polymerase chain reaction serve as important tools to differentiate CL from its clinical and histologic look-alikes. CL is discussed from various perspectives, with emphasis on CL and its broad differential diagnosis.


Assuntos
Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/patologia , Pele/patologia , Diagnóstico Diferencial , Erros de Diagnóstico , Técnicas e Procedimentos Diagnósticos , Humanos , Leishmania/genética , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Reação em Cadeia da Polimerase
7.
An Bras Dermatol ; 95(4): 459-468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32518010

RESUMO

BACKGROUND: American cutaneous leishmaniasis is an infectious dermatosis caused by protozoa of the genus Leishmania, which comprises a broad spectrum of clinical manifestations depending on the parasite species involved in the infections and the immunogenetic response of the host. The use of techniques for amplification of the parasites DNA based on polymerase chain reaction polymerase chain reaction and the recent application of combined techniques, such as high-resolution DNA dissociation, have been described as a viable alternative for the detection and identification of Leishmania spp. in biological samples. OBJECTIVES: To identify the Leishmania species using the polymerase chain reaction high-resolution DNA dissociation technique in skin biopsies of hospital-treated patients, and compare with results obtained by other molecular identification techniques. METHODS: A retrospective study assessing patients with suspected American cutaneous leishmaniasis seen at a hospital in São Paulo/Brazil was conducted. The paraffin blocks of 22 patients were analyzed by polymerase chain reaction high-resolution DNA dissociation to confirm the diagnosis and identify the species. RESULTS: Of the 22 patients with suspected American cutaneous leishmaniasis, the parasite was identified in 14, comprising five cases (35.6%) of infection by L. amazonensis, four (28.5%) by L. braziliensis, two (14.4%) by L. amazonensis+L. infantum chagasi, two (14.4%) by L. guyanensis, and one (7.1%) by Leishmania infantum chagasi. In one of the samples, in which the presence of amastigotes was confirmed on histopathological examination, the polymerase chain reaction high-resolution DNA dissociation technique failed to detect the DNA of the parasite. STUDY LIMITATIONS: The retrospective nature of the study and small number of patients. CONCLUSIONS: The method detected and identified Leishmania species in paraffin-embedded skin biopsies with a sensitivity of 96.4% and could be routinely used in the public health system.


Assuntos
Leishmania , Leishmaniose Cutânea/parasitologia , Brasil , Humanos , Leishmania infantum , Leishmaniose Mucocutânea , Estudos Retrospectivos , Estados Unidos
8.
Exp Parasitol ; 216: 107939, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32535115

RESUMO

Gaucher disease is a lysosomal storage disease in which a genetic deficiency in ß-glucocerebrosidase leads to the accumulation of glycosphingolipids in lysosomes. Macrophages are amongst the cells most severely affected in Gaucher disease patients. One phenotype associated with Gaucher macrophages is the impaired capacity to fight bacterial infections. Here, we investigate whether inhibition of ß-glucocerebrosidase activity affects the capacity of macrophages to phagocytose and act on the early containment of human pathogens of the genus Leishmania. Towards our aim, we performed in vitro infection assays on macrophages derived from the bone marrow of C57BL/6 mice. To mimic Gaucher disease, macrophages were incubated with the ß-glucocerebrosidase inhibitor, conduritol B epoxide (CBE), prior to contact with Leishmania. This treatment guaranteed that ß-glucocerebrosidase was fully inhibited during the contact of macrophages with Leishmania, its enzymatic activity being progressively recovered along the 48 h that followed removal of the inhibitor. Infections were performed with L. amazonensis, L. infantum, or L. major, so as to explore potential species-specific responses in the context of ß-glucocerebrosidase inactivation. Parameters of infection, recorded immediately after phagocytosis, as well as 24 and 48 h later, revealed no noticeable differences in the infection parameters of CBE-treated macrophages relative to non-treated controls. We conclude that blocking ß-glucocerebrosidase activity during contact with Leishmania does not interfere with the phagocytic capacity of macrophages and the early onset of leishmanicidal responses.


Assuntos
Glucosilceramidase/antagonistas & inibidores , Leishmania/fisiologia , Macrófagos/parasitologia , Fagocitose , Animais , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Doença de Gaucher/complicações , Doença de Gaucher/fisiopatologia , Glucosilceramidase/efeitos dos fármacos , Glucosilceramidase/genética , Inositol/análogos & derivados , Inositol/farmacologia , Leishmania infantum/fisiologia , Leishmania major/fisiologia , Leishmania mexicana/fisiologia , Lisossomos/efeitos dos fármacos , Lisossomos/enzimologia , Macrófagos/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Fagocitose/efeitos dos fármacos
9.
Exp Parasitol ; 216: 107940, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32562606

RESUMO

Therapeutic options for the treatment of leishmaniasis are insufficient and need improvements owing to their low efficiency and high toxicity as well as the emergence of resistant strains. The limited number of new drugs for neglected diseases and lack of innovation in your development are still challenges. In this context, the process of discovery and development of biological assays play a pivotal role for the identification of bioactive compounds. The assays currently used for screening of drugs with cytotoxic activity against Leishmania parasites, include different processes that utilize intact parasite (free or intracellular) or specific enzymes of metabolism as a target cell. These assays allow the screening of large numbers of samples followed by more detailed secondary confirmatory assays to confirm the observed activity and assess their toxicity. In the present study, we described the development of a new functional and more complete assay that enables simultaneous assessment of potential anti-Leishmania compounds through evaluation of internalization of fluorescein-labeled L. braziliensis promastigotes by human peripheral blood monocytes and their cytotoxicity by flow cytometry. We standardized the conditions for parasite labeling to achieve better phagocytosis analysis by setting the ratio of number of parasites per cell as 1 to 2, at incubation time of 6h. The cytotoxicity assessment was performed by the quantification of cells undergoing early/late apoptosis and necrosis using a double labelling platform employing 7AAD for late apoptosis and necrosis analysis and Annexin-V for early apoptosis evaluation. Hemolysis analysis was an additional parameter to test cytotoxicity. Two drugs used on clinic (Amphotericin B and Glucantime®) were used to validate the proposed methodology, and the assay was able to detect their known leishmanicidal activity and immunotoxicity properties. This new predictive assay will contribute to the development of translational medicine strategies in drug discovery for neglected diseases such as leishmaniasis.


Assuntos
Alternativas aos Testes com Animais/métodos , Antiprotozoários/toxicidade , Citometria de Fluxo/métodos , Leishmania/efeitos dos fármacos , Doenças Negligenciadas/tratamento farmacológico , Adulto , Anfotericina B/farmacologia , Anfotericina B/toxicidade , Animais , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Humanos , Leishmania braziliensis/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Leucócitos/efeitos dos fármacos , Leucócitos/parasitologia , Antimoniato de Meglumina/farmacologia , Antimoniato de Meglumina/uso terapêutico , Antimoniato de Meglumina/toxicidade , Microscopia Confocal , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Monócitos/parasitologia , Fatores de Tempo , Adulto Jovem
10.
Parasitol Res ; 119(7): 2025-2037, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32504119

RESUMO

Leishmaniasis is a neglected tropical disease with no effective vaccines to date. Globally, it affects around 14 million people living in undeveloped and developing countries. Leishmania, which is the causative eukaryotic organism, possesses unique enzymes and pathways that deviates from its mammalian hosts. The control strategy against leishmaniasis currently depends on chemotherapeutic methods. But these chemotherapeutic therapies possess several side effects, and therefore, the identification of potential drug targets has become very crucial. Identification of suitable drug targets is necessary to design specific inhibitors that can target and control the parasite. These unique enzymes can be used as possible drug targets after biochemical characterization and understanding the role of these enzymes. In this review, the authors discuss various metabolic pathways that are essential for the survival of the parasite and can be exploited as potential drug targets against leishmaniasis.


Assuntos
Antiparasitários , Leishmania/metabolismo , Leishmaniose/tratamento farmacológico , Redes e Vias Metabólicas/efeitos dos fármacos , Terapia de Alvo Molecular , Animais , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Leishmania/efeitos dos fármacos
11.
PLoS One ; 15(6): e0234445, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579586

RESUMO

This study aimed to describe the sand fly fauna and detect trypanosomatids in these insects from Casa Branca, state of Minas Gerais, Brazil, an endemic area of both visceral (VL) and tegumentary leishmaniasis (TL). Sand flies were collected bimonthly from May 2013 to July 2014, using automatic light traps exposed for three consecutive nights in peridomiciliary areas of nine houses with previous reports of VL and TL. ITS1-PCR and DNA sequencing were performed for trypanosomatids identification. A total of 16,771 sand flies were collected belonging to 23 species. The most abundant species was Nyssomyia whitmani (Antunes & Coutinho, 1939) (70.9%), followed by Lutzomyia longipalpis (Lutz & Neiva, 1912) (15.2%) and Migonemyia migonei (França, 1920) (9.1%). Leishmania amazonensis DNA was detected in Ny. whitmani (four pools) and Le. braziliensis DNA was detected in Psychodopygus lloydi (one pool). In seven pools of Ny. whitmani and in one pool of Lu. longipalpis positive for Leishmania DNA, the parasite species was not determined due to the low quality of the sequences. Moreover, DNA of Herpetomonas spp. was detected in Ny. whitmani (two pools) and Cortelezzii complex (one pool). DNA of Crithidia spp. was detected in Ny. whitmani and Ps. lloydi (both one pool). Our results suggest that Ny. whitmani may be involved in the transmission of Le. amazonensis in the study area. The molecular detection of Le. amazonensis suggests the presence of this species in a sylvatic cycle between vertebrate and invertebrate hosts in the region of Casa Branca. Our data also reveal the occurrence of other non-Leishmania trypanosomatids in sand flies in Casa Branca District.


Assuntos
Biodiversidade , Insetos Vetores/parasitologia , Leishmania/isolamento & purificação , Phlebotomus/parasitologia , Psychodidae/parasitologia , Animais , Brasil/epidemiologia , DNA de Protozoário/isolamento & purificação , Doenças Endêmicas/prevenção & controle , Feminino , Humanos , Leishmania/genética , Leishmaniose/epidemiologia , Leishmaniose/parasitologia , Leishmaniose/prevenção & controle , Leishmaniose/transmissão , Análise de Sequência de DNA
12.
Pediatrics ; 146(1)2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32532792

RESUMO

An 8-year-old boy with no significant past medical history presented to his pediatrician with 5 days of fever, diffuse abdominal pain, and pallor. The pediatrician referred the patient to the emergency department (ED), out of concern for possible malignancy. Initial vital signs indicated fever, tachypnea, and tachycardia. Physical examination was significant for marked abdominal distension, hepatosplenomegaly, and abdominal tenderness in the right upper and lower quadrants. Initial laboratory studies were notable for pancytopenia as well as an elevated erythrocyte sedimentation rate and C-reactive protein. Computed tomography (CT) of the abdomen and pelvis showed massive splenomegaly. The only significant history of travel was immigration from Albania 10 months before admission. The patient was admitted to a tertiary care children's hospital and was evaluated by hematology-oncology, infectious disease, genetics, and rheumatology subspecialty teams. Our multidisciplinary panel of experts will discuss the evaluation of pancytopenia with apparent multiorgan involvement and the diagnosis and appropriate management of a rare disease.


Assuntos
Febre/diagnóstico , Leishmaniose Visceral/complicações , Pancitopenia/diagnóstico , Esplenomegalia/diagnóstico , Criança , Diagnóstico Diferencial , Febre/etiologia , Humanos , Leishmania/isolamento & purificação , Leishmaniose Visceral/diagnóstico , Masculino , Pancitopenia/etiologia , Esplenomegalia/etiologia , Tomografia Computadorizada por Raios X
13.
Korean J Parasitol ; 58(2): 173-179, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32418386

RESUMO

Leishmaniasis is a prevalent cause of death and animal morbidity in underdeveloped countries of endemic area. However, there is few vaccine and effective drugs. Antimicrobial peptides are involved in the innate immune response in many organisms and are being developed as novel drugs against parasitic infections. In the present study, we synthesized a 5-amino acid peptide REDLK, which mutated the C-terminus of Pseudomonas exotoxin, to identify its effect on the Leishmania tarentolae. Promastigotes were incubated with different concentration of REDLK peptide, and the viability of parasite was assessed using MTT and Trypan blue dye. Morphologic damage of Leishmania was analyzed by light and electron microscopy. Cellular apoptosis was observed using the annexin V-FITC/PI apoptosis detection kit, mitochondrial membrane potential assay kit and flow cytometry. Our results showed that Leishmania tarentolae was susceptible to REDLK in a dose-dependent manner, disrupt the surface membrane integrity and caused parasite apoptosis. In our study, we demonstrated the leishmanicidal activity of an antimicrobial peptide REDLK from Pseudomonas aeruginosa against Leishmania tarentolae in vitro and present a foundation for further research of anti-leishmanial drugs.


Assuntos
Proteínas de Bactérias/farmacologia , Leishmania/efeitos dos fármacos , Leishmania/crescimento & desenvolvimento , Peptídeos/farmacologia , Pseudomonas/metabolismo , Técnicas In Vitro
14.
Hautarzt ; 71(6): 437-442, 2020 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-32394080

RESUMO

Here we describe two complicated cases of complex Old World cutaneous Leishmaniasis due to L. infantum and L. aethiopica. Both of our patients infected with the Leishmania parasite presented with a completely different clinical picture, course of disease, and treatment response. Clinical healing was achieved after multiple courses of treatment with a variety of different antileishmanial drugs. Nephrotoxity was a limiting side effect.


Assuntos
Leishmania infantum/isolamento & purificação , Leishmania/isolamento & purificação , Leishmaniose Cutânea/diagnóstico , Anti-Infecciosos/efeitos adversos , Anti-Infecciosos/uso terapêutico , Antiprotozoários/efeitos adversos , Antiprotozoários/uso terapêutico , Progressão da Doença , Humanos , Leishmania/classificação
15.
Int J Infect Dis ; 97: 27-29, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32425641

RESUMO

BACKGROUND: Visceral leishmaniasis-related hemophagocytic lymphohistiocytosis (VL-HLH) is a secondary hemophagocytic syndrome, which can be life-threatening, caused by leishmania and transmitted by infected sandflies. Rapid and accurate identification of leishmania is crucial for clinical strategies. CASE REPORT: Here, we report an infantile infection in a non-epidemic area of China. The infant was a 9.5-month-old girl with fever, pancytopenia and hepatosplenomegaly, which meet the HLH-2004 standard, and the negative gene results exclude congenital HLH. However, chemotherapy is ineffective and is accompanied by severe infection. Fortunately, she is diagnosed with VL-HLH (visceral leishmaniasis-related hemophagocytic lymphohistiocytosis), as leishmania is detected by next-generation meta-genome sequencing (mNGS) and quickly relieved after treatment with libosomal amphotericin B (L-AMB). CONCLUSION: mNGS can detect leishmania in pediatric HLH, and should be performed as a new detection for VL-HLH, particularly for infants, who may not respond to HLH-2004 regimen.


Assuntos
Leishmaniose Visceral/diagnóstico , Linfo-Histiocitose Hemofagocítica/diagnóstico , Anfotericina B/uso terapêutico , Antiprotozoários/uso terapêutico , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Leishmania/isolamento & purificação , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Linfo-Histiocitose Hemofagocítica/tratamento farmacológico , Linfo-Histiocitose Hemofagocítica/parasitologia
16.
Braz J Infect Dis ; 24(3): 201-207, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32343952

RESUMO

Cysteine proteinases are well-known virulence factors of Leishmania spp. with demonstrated actions in both experimental mouse infection and human infection. However, studies on these enzymes in canine leishmaniasis are scarce. Here, we show, for the first time, the reactivity of sera from dogs living in an endemic area to a recombinant protein from the COOH-terminal region of cysteine B protease. In this work, enzyme-linked immunosorbent assays were performed using a 14kDa rcyspep protein obtained through a pET28-a expression system in Escherichia coli. First, 96-well plates were coated with rcyspep (500ng/well) and incubated with sera from dogs (1:100). Subsequently, IgG antibody detection was performed using rabbit anti-dog IgG antibodies conjugated with peroxidase. Sera from dogs (n=114), including suspect (n=30) and positive (n=50) dogs from a leishmaniasis-endemic area and dogs from a nonendemic area, (n=34), negative for leishmaniasis, were assessed. The results showed that sera from the suspect (42%) and positive (68%) groups responded differently to the antigen titers tested above the cut-off (Optical Density=0.166). This finding suggests that the immune response detected against cyspep may be related to clinical disorders present in these animals. Collectively, the data gathered here suggest that cyspep can sensitize the immune systems of dogs from a leishmaniasis-endemic area to elicit a humoral response, an immunological parameter indicating the contribution of this protein in host-parasite interaction.


Assuntos
Cisteína Proteases/sangue , Doenças do Cão/sangue , Leishmania , Leishmaniose/sangue , Animais , Anticorpos Antiprotozoários , Cisteína , Cães , Ensaio de Imunoadsorção Enzimática , Humanos , Leishmania infantum , Leishmaniose/veterinária , Leishmaniose Visceral , Camundongos , Coelhos
17.
BMC Public Health ; 20(1): 446, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-32248804

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) is caused by protozoa of the Leishmania donovani complex. Annually, an estimated 500,000 cases of VL are reported globally posing a public health challenge. The objectives of our study were to confirm and determine the magnitude of VL outbreak, characterize the outbreak clinically and epidemiologically and evaluate the county preparedness and response in Marsabit County, Kenya. METHODS: A retrospective review of laboratory registers and patients' clinical notes was done at Marsabit County Hospital. Cases were persons with confirmed VL diagnosis either by microscopy, serology or molecular technique coming from Marsabit County from May to October 2014. Cases were interviewed using structured questionnaire to collect clinical and epidemiologic information. Blood samples were collected from cases for laboratory confirmation. RESULTS: A total of 136 cases were confirmed of which 77% (105) were male with a median age of 17 (IQR: 22) years and 9.6% (13) case fatality rate. All cases were admitted at Marsabit County Referral Hospital, Kenya. Medical records of 133 cases were retrieved. Of the 133 cases, 102 (77%) presented with fever, 43 (32%) with splenomegaly, 26 (20%) with hepatomegaly and 96 (72%) were managed with Sodium stibogluconate (SSG) monotherapy. Thirty-four cases (26%) received Full haemogram (FHG) test and none had more than one Liver Function Tests (LFTs) in a span of 6 months. Presenting with headache (OR: 4.21, 95% CI: 1.10-16.09) and hepatomegaly (OR: 4.2, 95% CI: 1.30-14.11) were associated with VL death. No VL case management training had been conducted nor VL treatment guidelines distributed among health care workers (HCWs) in the last 1 year. CONCLUSIONS: VL cases were confirmed. Inadequate case monitoring and management was evident. VL case management sensitization training was conducted. The County health department should put in place one health VL surveillance and facilitate periodic case management trainings.


Assuntos
Surtos de Doenças , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Febre/epidemiologia , Humanos , Lactente , Quênia/epidemiologia , Leishmania/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
18.
Parasite Immunol ; 42(7): e12722, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32294247

RESUMO

Leishmaniasis is a neglected infectious disease with clinical presentations ranging from asymptomatic or mild symptoms to chronic infection and eventual death. The mechanisms of disease susceptibility and pathology have been extensively studied, but there are no steadfast rules regarding leishmaniasis. A Th1 response is usually associated with infection control, while a predominant Th2 response is detrimental to the patient. In this scenario, the enzymes arginase and inducible nitric oxide synthase represent two possible pathways of immune response. While the former contributes to parasite replication, the latter is crucial for its control. In the present review, we collected study results that associate arginase expression in patients and in experimental models with disease susceptibility/chronicity and show some proposed mechanisms that explain the role of arginase in maintaining Leishmania infection, including polyamine and thiol synthesis, tissue-resident macrophage (TRM) proliferation and activation and T-cell suppression and exhaustion.


Assuntos
Arginase/metabolismo , Leishmania/imunologia , Leishmaniose/imunologia , Macrófagos/imunologia , Óxido Nítrico Sintase Tipo II/metabolismo , Animais , Linfócitos T CD8-Positivos/imunologia , Humanos , Imunidade Inata/imunologia , Leishmaniose/parasitologia , Neutrófilos/imunologia , Células Th1/imunologia , Células Th2/imunologia
19.
Am J Trop Med Hyg ; 102(6): 1323-1327, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32228793

RESUMO

Multiple polymerase chain reaction (PCR)-based approaches have been developed for Leishmania detection in clinical and laboratory samples, and this diversity limits inter-study comparisons, meta-analyses, and generalization of findings. Towards harmonization of a molecular tool for detection of Leishmania (Viannia) for research purposes, we evaluated the concordance of 18SrDNA quantitative polymerase chain reaction (qPCR) and minicircle kinetoplastid DNA (mkDNA) PCR followed by Southern blot (PCR-SB) in in vitro infection systems and in lesion and mucosal swab samples from Colombian patients with cutaneous leishmaniasis caused by L. (Viannia). The lower limit of parasite detection of 18SrDNA qPCR and mkDNA PCR-SB was 10-1 promastigotes and one intracellular amastigote per reaction. From cutaneous lesions (n = 63), an almost perfect concordance was found between the methods (κ = 0.92, 95% CI: 0.82-1.00). Despite equal limits of detection, mkDNA PCR-SB was more efficient for parasite detection in mucosal samples than 18SrDNA qPCR or 18SrDNA digital droplet PCR. The high concordance, sensitivity, scaling potential, and feasibility of implementation of the 18SrDNA qPCR, support its selection as the L. (Viannia) in research laboratories, as a first step towards harmonization of research protocols in the region.


Assuntos
DNA de Protozoário/genética , Leishmania/isolamento & purificação , Leishmaniose/diagnóstico , Leishmaniose/parasitologia , Técnicas de Amplificação de Ácido Nucleico , Linhagem Celular , Túnica Conjuntiva/parasitologia , Feminino , Humanos , Limite de Detecção , Masculino , Monócitos/parasitologia , Mucosa Nasal/parasitologia , Tonsila Palatina/parasitologia , Especificidade da Espécie
20.
PLoS One ; 15(4): e0230610, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240188

RESUMO

BACKGROUND: The development of rK39-based immunochromatographic rapid diagnostic tests represents an important advance for serodiagnosis of visceral leishmaniasis, being cheap and easy to use at the point of care (POC). Although the use of rK39 have considerably improved the sensitivity and specificity of serological tests compared with total antigens, great variability in sensitivity and specificity was reported. This study aimed at the evaluation of "Kalazar Detect™ Rapid Test, Whole Blood" (Kalazar Detect RDT) for Visceral Leishmaniasis (VL) diagnosis using oral fluid, whole blood and serum specimens collected at different endemic areas of VL of Brazil. METHODOLOGY: To evaluate Kalazar Detect RDT, oral fluid, whole blood and serum specimens from 128 VL patients, 85 healthy individuals, 22 patients with possible cross-reactivity diseases and 20 VL/aids coinfected patients were collected and assayed at the POC. PRINCIPAL FINDINGS AND CONCLUSIONS: The performance of Kalazar Detect RDT in whole blood and serum was similar; however, using oral fluid, the sensitivity was low. Particularly in samples from the city of Natal, Rio Grande do Norte state in Northeastern Brazil, we observed low sensitivity, 80.0% (95% CI: 62.7-90.5), using whole blood and serum, and poor sensitivity, 43.3% (95% CI: 27.4-60.8) with oral fluid. Those values were much lower than in the other regions, where sensitivity ranged from 92.7-96.3% in whole blood and serum, and 80.0-88.9% in oral fluid. Besides, in VL/aids coinfected patients, lower sensitivity was achieved compared with VL patients. In samples from Natal, the sensitivity was 0.0% (95% CI: 0.0-49.0) and 25.0% (95% CI: 4.6-69.9), using oral fluid and serum/whole blood, respectively; in samples from the other regions, the sensitivity ranged from 40.0-63.6% and 80.0-81.8%, respectively. As for specificity, high values were observed across the fluids, 100.0% (95% CI: 96.5-100.0) in whole blood, 96.3% (95% CI: 90.8-98.5) in serum, and 95.3% (95% CI: 89.5-98.0) in oral fluid; across localities, specificity ranged from 85.7-100.0%. Serum samples sent by the collaborating centers to Instituto de Medicina Tropical (n = 250) were tested by Kalazar Detect RDT, Direct Agglutination Test, Indirect immunofluorescence assay, Enzyme-linked immunosorbent assay, and IT-Leish® RDT. The regional difference in the performance of rK39-based RDT and lower sensitivity in Leishmania/HIV coinfected patients raise concern on the routine use of these products for the diagnosis of VL.


Assuntos
Líquidos Corporais/química , Cromatografia de Afinidade/métodos , Testes Diagnósticos de Rotina/métodos , Leishmania/isolamento & purificação , Leishmaniose Visceral/diagnóstico , Proteínas de Protozoários/imunologia , Testes Sorológicos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Lactente , Leishmaniose Visceral/sangue , Leishmaniose Visceral/epidemiologia , Masculino , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito , Adulto Jovem
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