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1.
Arch Pharm (Weinheim) ; 356(7): e2300108, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37068175

RESUMO

In the last decade, the World Health Organization has driven the development of drugs for topical use in patients with cutaneous leishmaniasis (CL), the most prevalent clinical form of leishmaniasis, a neglected tropical disease. The chemicals C6 I, TC1, and TC2 were reported as promising antileishmanial drugs. We aimed to develop a topical nanoformulation that enhances the advantageous effect of C6 I, TC1, and TC2, guaranteeing higher stability and bioavailability of the pharmacologically active components through the topical route. Nanoemulsions were prepared by ultrasonication based on oleic acid (0.5 g). A relation of Tween®-80/ethanol (1:3) and water was obtained; physicochemical characterization of all formulations was performed, and the preliminary stability and transdermal penetration of these nanoemulsions were also investigated. Newtonian-type fluids with high load capacity, 147-273 nm globule size, and -15 to -18 mV zeta potential were obtained with differential permeability rates in the first pig ear skin assay, first-order kinetics-release model for C6 I, and Weibull for TC1 and TC2. The nanoemulsion showed good stability, high encapsulation efficiency, and higher leishmanicidal activity against Leishmania braziliensis with lower cytotoxicity in U937 macrophages. In conclusion, nanoemulsions of ethanol-oleic acid/Tween®-80 increase the activity of compounds with leishmanicidal activity by increasing their penetration and sustained release.


Assuntos
Ácido Oleico , Polissorbatos , Animais , Suínos , Preparações de Ação Retardada , Polissorbatos/farmacologia , Emulsões/química , Relação Estrutura-Atividade
2.
N Engl J Med ; 380(3): 229-241, 2019 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-30650326

RESUMO

BACKGROUND: Tafenoquine, a single-dose therapy for Plasmodium vivax malaria, has been associated with relapse prevention through the clearance of P. vivax parasitemia and hypnozoites, termed "radical cure." METHODS: We performed a phase 3, prospective, double-blind, double-dummy, randomized, controlled trial to compare tafenoquine with primaquine in terms of safety and efficacy. The trial was conducted at seven hospitals or clinics in Peru, Brazil, Colombia, Vietnam, and Thailand and involved patients with normal glucose-6-phosphate dehydrogenase (G6PD) enzyme activity and female patients with moderate G6PD enzyme deficiency; all patients had confirmed P. vivax parasitemia. The patients were randomly assigned, in a 2:1 ratio, to receive a single 300-mg dose of tafenoquine or 15 mg of primaquine once daily for 14 days (administered under supervision); all patients received a 3-day course of chloroquine and were followed for 180 days. The primary safety outcome was a protocol-defined decrease in the hemoglobin level (>3.0 g per deciliter or ≥30% from baseline or to a level of <6.0 g per deciliter). Freedom from recurrence of P. vivax parasitemia at 6 months was the primary efficacy outcome in a planned patient-level meta-analysis of the current trial and another phase 3 trial of tafenoquine and primaquine (per-protocol populations), and an odds ratio for recurrence of 1.45 (tafenoquine vs. primaquine) was used as a noninferiority margin. RESULTS: A protocol-defined decrease in the hemoglobin level occurred in 4 of 166 patients (2.4%; 95% confidence interval [CI], 0.9 to 6.0) in the tafenoquine group and in 1 of 85 patients (1.2%; 95% CI, 0.2 to 6.4) in the primaquine group, for a between-group difference of 1.2 percentage points (95% CI, -4.2 to 5.0). In the patient-level meta-analysis, the percentage of patients who were free from recurrence at 6 months was 67.0% (95% CI, 61.0 to 72.3) among the 426 patients in the tafenoquine group and 72.8% (95% CI, 65.6 to 78.8) among the 214 patients in the primaquine group. The efficacy of tafenoquine was not shown to be noninferior to that of primaquine (odds ratio for recurrence, 1.81; 95% CI, 0.82 to 3.96). CONCLUSIONS: Among patients with normal G6PD enzyme activity, the decline in hemoglobin level with tafenoquine did not differ significantly from that with primaquine. Tafenoquine showed efficacy for the radical cure of P. vivax malaria, although tafenoquine was not shown to be noninferior to primaquine. (Funded by GlaxoSmithKline and Medicines for Malaria Venture; GATHER ClinicalTrials.gov number, NCT02216123 .).


Assuntos
Aminoquinolinas/administração & dosagem , Antimaláricos/administração & dosagem , Malária Vivax/tratamento farmacológico , Plasmodium vivax , Primaquina/administração & dosagem , Prevenção Secundária/métodos , Adolescente , Adulto , Aminoquinolinas/efeitos adversos , Antimaláricos/efeitos adversos , Cloroquina/uso terapêutico , Intervalo Livre de Doença , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/complicações , Hemoglobinas/análise , Humanos , Estimativa de Kaplan-Meier , Malária Vivax/complicações , Masculino , Parasitemia/tratamento farmacológico , Plasmodium vivax/isolamento & purificação , Primaquina/efeitos adversos , Estudos Prospectivos
3.
Pharmacogenet Genomics ; 30(7): 161-165, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32433338

RESUMO

Plasmodium vivax has the largest geographic range of human malaria species and is challenging to manage and eradicate due to its ability to establish a dormant liver stage, the hypnozoite, which can reactivate leading to relapse. Until recently, the only treatment approved to kill hypnozoites was the 8-aminoquinoline, primaquine, requiring daily treatment for 14 days. Tafenoquine, an 8-aminoquinoline single-dose treatment with activity against P. vivax hypnozoites, has recently been approved by the US Food and Drug Administration and Australian Therapeutic Goods Administration for the radical cure of P. vivax malaria in patients 16 years and older. We conducted an exploratory pharmacogenetic analysis (GSK Study 208099) to assess the role of host genome-wide variation on tafenoquine efficacy in patients with P. vivax malaria using data from three GSK clinical trials, GATHER and DETECTIVE Part 1 and Part 2. Recurrence-free efficacy at 6 and 4 months and time to recurrence up to 6 months postdosing were analyzed in 438 P. vivax malaria patients treated with tafenoquine. Among the approximately 10.6 million host genetic variants analyzed, two signals reached genome-wide significance (P value ≤ 5 × 10). rs62103056, and variants in a chromosome 12 intergenic region, were associated with recurrence-free efficacy at 6 and 4 months, respectively. Neither of the signals has an obvious biological rationale and would need replication in an independent population. This is the first genome-wide association study to evaluate genetic influence on response to tafenoquine in P. vivax malaria.


Assuntos
Aminoquinolinas/administração & dosagem , Antimaláricos/administração & dosagem , Cromossomos Humanos Par 12/genética , Malária Vivax/tratamento farmacológico , Polimorfismo de Nucleotídeo Único , Adulto , Aminoquinolinas/farmacologia , Antimaláricos/farmacologia , Ensaios Clínicos como Assunto , Feminino , Estudo de Associação Genômica Ampla , Humanos , Malária Vivax/genética , Masculino , Pessoa de Meia-Idade , Testes Farmacogenômicos , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
4.
Arch Pharm (Weinheim) ; 353(5): e1900351, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32187709

RESUMO

A new series of N-substituted pyrazoline derivatives 6a-g, 7a-g, 8a-g, and 9a-g was synthetized by reaction of hydrazine derivatives and chalcone-thiazole hybrids bearing nitrogen mustard 5a-g. The chalcones 5a-g were obtained by Claisen-Schmidt condensation of thiazole-2-nitrogen mustard 3 and selected acetophenones 4a-g. These new compounds 6/7/8/9a-g were screened for their antifungal activity against Cryptococcus neoformans, with IC50 values of 3.9-7.8 µg/ml for the N-3,5-dichlorophenyl pyrazolines 9e-g. Interestingly, those compounds show low cytotoxic effects toward erythrocytes (RBC). In addition, N-acetyl (6a,b) and N-formyl pyrazolines (7a, 7b, 7c, and 7g) showed inhibitory activity against methicillin-susceptible Staphylococcus aureus, methicillin-resistant S. aureus, and vancomycin-intermediate S. aureus, with the most important minimum inhibitory concentration values ranging from 31.25 to 125 µg/ml. Regarding the antiprotozoal activity, thiazolyl-pyrazolines 9g, 8f, and 7c display high activity against Plasmodium falciparum, Leishmania (V) panamensis, and Trypanosoma cruzi, with EC50 values of 11.80, 6.46, and 4.98 µM, respectively, and with 7c being approximately 2.6-fold more potent than benznidazole with a selectivity index of 1.61 on U-937 human cells, showing promising potential as a novel antitrypanosomal agent.


Assuntos
Antibacterianos/farmacologia , Antiprotozoários/farmacologia , Mecloretamina/farmacologia , Pirazóis/farmacologia , Tiazóis/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antiprotozoários/síntese química , Antiprotozoários/química , Relação Dose-Resposta a Droga , Leishmania/efeitos dos fármacos , Mecloretamina/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Testes de Sensibilidade Parasitária , Plasmodium falciparum/efeitos dos fármacos , Pirazóis/química , Relação Estrutura-Atividade , Tiazóis/química , Trypanosoma cruzi/efeitos dos fármacos , Staphylococcus aureus Resistente à Vancomicina/efeitos dos fármacos
5.
Exp Parasitol ; 201: 78-89, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31047987

RESUMO

Hamsters are a suitable experimental model for visceral leishmaniasis (VL) because they mimic the features of the human disease. However, the infection after inoculation can only be verified after sacrifice of the animal or several months following infection, when obvious signs of the disease appear, compromising animal welfare in both cases. Unlike other studies, the present work used an inoculum of 5 × 108 promastigotes to induce Leishmania infantum infection, which are easier to produce than amastigotes, in in vitro culture. The infection in hamsters was detected using non-invasive methods such as ultrasound imaging (USG) and blood gases, in addition to alterations in hematological parameters and weight loss. USG imaging identified changes in the size and echogenicity of the spleen, liver, and kidney as early as week 9 (W9) after experimental inoculation. However, blood gases, specially lactate, was increased in response to the infection, with statistically significant differences between W9 and W0 (before infection) (p < 0.0001). The conventional hematological parameters showed progressive pancytopenia and weight loss of 15% and 10% in infected males and females respectively, at W9 versus W0 (p < 0.0001). Histological changes in the liver, kidney, and spleen correlated with changes detected by USG imaging and the number of parasites increased proportionately to the progression of infection, being higher at W24. In conclusion, USG imaging, lactate levels, hematocrit and hemoglobin parameters, along with weight loss allowed early detection of infection, which was then confirmed by the identification and quantification of parasites in the blood, liver, and spleen by qRT-PCR. In contrast, blood chemistry was not a useful tool in the early detection of VL infection because it did not correlate with alterations evident in other techniques. The use of non-invasive tools eliminates the need for animal sacrifice to confirm infection, thus reducing the number of animals required for a given study and eliminating the need to wait until the appearance of severe signs of infection, which affect animal welfare. These tools are therefore advantageous for use in preclinical studies, for studying pathogenesis as also for vaccine and drug development.


Assuntos
Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/diagnóstico , Animais , Análise Química do Sangue , Gasometria , Cricetinae , Modelos Animais de Doenças , Feminino , Testes Hematológicos , Rim/diagnóstico por imagem , Rim/patologia , Leishmania infantum/classificação , Leishmaniose Visceral/sangue , Leishmaniose Visceral/diagnóstico por imagem , Fígado/diagnóstico por imagem , Fígado/parasitologia , Fígado/patologia , Masculino , Mesocricetus , Reação em Cadeia da Polimerase em Tempo Real , Fatores Sexuais , Baço/diagnóstico por imagem , Baço/parasitologia , Baço/patologia , Ultrassonografia , Aumento de Peso
6.
Parasitol Res ; 117(1): 273-286, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29230580

RESUMO

The physicochemical properties of four N-halomethylated and one non-halomethylated ammonium salts, with proven in vitro antileishmanial activity, were determined according to pharmaceutical standard procedures. The effectiveness and toxicity of these compounds were assessed in hamsters infected with Leishmania (Viannia) braziliensis and compared to that showed by meglumine antimoniate. Animals were followed during 90 days after the completion of treatment. Therapeutic response was determined according to the reduction of size of skin lesions. Toxicity was determined by the effect of compounds on body weight changes and serum levels of renal and hepatic metabolites. The effectiveness of compound 4 was similar to that showed by intralesional administration of meglumine antimoniate and better than that of the other ammonium salts. Levels of creatinine, alanine amino transferase, and blood urea nitrogen in serum were not significantly different between treatment groups, including healthy or untreated hamsters. Results imply that compound 4 has potential as a pharmaceutical active ingredient in the development of new and better formulations for the treatment of cutaneous leishmaniasis.


Assuntos
Antiprotozoários/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Compostos de Amônio Quaternário/farmacologia , Administração Tópica , Animais , Antiprotozoários/química , Peso Corporal/efeitos dos fármacos , Cricetinae , Modelos Animais de Doenças , Feminino , Leishmaniose Cutânea/parasitologia , Masculino , Meglumina/farmacologia , Antimoniato de Meglumina , Compostos Organometálicos/farmacologia , Compostos de Amônio Quaternário/química , Sais , Pele/parasitologia , Testes de Toxicidade
7.
Molecules ; 23(1)2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29329207

RESUMO

In search for potential therapeutic alternatives to existing treatments for cutaneous Leishmaniasis, we have investigated the effect of Arnica tincture Ph. Eur. (a 70% hydroethanolic tincture prepared from flowerheads of Arnica montana L.) on the lesions caused by infection with Leishmania braziliensis in a model with golden hamsters. The animals were treated topically with a daily single dose of the preparation for 28 days. Subsequently, the healing process was monitored by recording the lesion size in intervals of 15 days up to day 90. As a result, Arnica tincture fully cured three out of five hamsters while one animal showed an improvement and another one suffered from a relapse. This result was slightly better than that obtained with the positive control, meglumine antimonate, which cured two of five hamsters while the other three showed a relapse after 90 days. This result encourages us to further investigate the potential of Arnica tincture in the treatment of cutaneous Leishmaniasis.


Assuntos
Antiprotozoários/química , Arnica/química , Lactonas/química , Leishmaniose Cutânea/tratamento farmacológico , Extratos Vegetais/química , Animais , Antiprotozoários/isolamento & purificação , Antiprotozoários/uso terapêutico , Cricetinae , Relação Dose-Resposta a Droga , Feminino , Lactonas/isolamento & purificação , Lactonas/uso terapêutico , Leishmania braziliensis/efeitos dos fármacos , Masculino , Antimoniato de Meglumina/farmacologia , Antimoniato de Meglumina/uso terapêutico , Mesocricetus , Extratos Vegetais/uso terapêutico , Relação Estrutura-Atividade
8.
Parasitology ; 144(13): 1718-1725, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28831945

RESUMO

Current chemotherapeutic agents for leishmaniasis have several disadvantages interfering with the effective treatment and therefore more and better antileishmanial drugs are needed. Discovery of candidates for leishmaniasis treatment requires not only accurate and precise methodologies but also well-known biological system to measure infectivity of parasites and antileishmanial activity of the new compounds. Significant variation in the in vitro and in vivo infectivity and sensitivity to established and experimental drugs in Leishmania strains are reported. This work reports the in vitro biological behavior and antileishmanial drugs sensitivity of different green fluorescent protein transfectant Leishmanias strains. The in vitro growth kinetic and infectivity to U937 cells vary slightly in the Leishmania transfectant strains in comparison with their correspondant wild-type. However, the insertion of the pIR3(-)-eGFP may affect the sensitivity of the parasites to meglumine antimoniate (MA) and miltefosine but not to amphotericin B (AMB) and pentamidine isethionate. In consequence, AMB or pentamidine isethionate but not MA or miltefosine should be used as antileishmanial control drugs during in vitro assays of antileishmanial activity. Furthermore, is recommended to test compounds against more than one Leishmania strain in order to verify that the antileihmanial activity of these compound is similar among species.


Assuntos
Antiprotozoários/farmacologia , Proteínas de Fluorescência Verde/genética , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Testes de Sensibilidade Parasitária , Especificidade da Espécie , Transfecção
9.
Molecules ; 22(12)2017 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-29186046

RESUMO

The S-containing heterocyclic compounds benzothiopyrans or thiochromones stand out as having promising biological activities due to their structural relationship with chromones (benzopyrans), which are widely known as privileged scaffolds in medicinal chemistry. In this work, we report the synthesis of 35 thiochromone derivatives and the in vitro antileishmanial and cytotoxic activities. Compounds were tested against intracellular amastigotes of Leishmania panamensis and cytotoxic activity against human monocytes (U-937 ATCC CRL-1593.2). Compounds bearing a vinyl sulfone moiety, 4h, 4i, 4j, 4k, 4l and 4m, displayed the highest antileishmanial activity, with EC50 values lower than 10 µM and an index of selectivity over 100 for compounds 4j and 4l. When the double bond or the sulfone moiety was removed, the activity decreased. Our results show that thiochromones bearing a vinyl sulfone moiety are endowed with high antileishmanial activity and low cytotoxicity.


Assuntos
Antiprotozoários/síntese química , Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Tiamina/análogos & derivados , Antiprotozoários/química , Técnicas de Química Sintética , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Tiamina/síntese química , Tiamina/química , Tiamina/farmacologia
10.
Parasitology ; 143(9): 1133-42, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27174193

RESUMO

Leishmaniasis is a parasitic infection caused by several species of the genus Leishmania that is considered as a neglected disease. Drug development process requires a robust and updated high-throughput technology to the evaluation of candidate compounds that imply the manipulation of the pathogenic species of the parasite in the laboratory. Therefore, it is restricted to trained personal and level II biosafety environments. However, it has been established the utility of Leishmania tarentolae as a model for in vitro screening of antileishmanial agents without the necessity of level II biosafety setups. In parallel the transfection of Leishmania parasites with reporter genes as the eGFP using non-commercial integration vectors like the pIRmcs3(-) has proved to be a powerful tool for the implementation of semi automatized high-throughput platforms for the evaluation of antileishmanial compounds. Here we report the generation of a new L. tarentolae strain overexpressing the eGFP gene harboured by the non-commercial vector pIR3(-). We also demonstrate its utility for the semi-automatized screening of antileshmanial compounds in intracellular forms of the L. tarentolae parasite.


Assuntos
Antiprotozoários/farmacologia , Leishmania/genética , Leishmaniose/parasitologia , Doenças Negligenciadas/parasitologia , Organismos Geneticamente Modificados/genética , Antiprotozoários/uso terapêutico , Biologia Computacional , Descoberta de Drogas , Citometria de Fluxo , Expressão Gênica , Genes Reporter , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Ensaios de Triagem em Larga Escala , Humanos , Concentração Inibidora 50 , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Doenças Negligenciadas/tratamento farmacológico , RNA Ribossômico 18S/genética , Segurança , Células U937
11.
Molecules ; 21(4): 381, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-27043509

RESUMO

This work describes the synthesis of a series of quaternary ammonium salts and the assessment of their in vitro antileishmanial activity and cytotoxicity. A preliminary discussion on a structure-activity relationship of the compounds is also included. Three series of quaternary ammonium salts were prepared: (i) halomethylated quaternary ammonium salts (series I); (ii) non-halogenated quaternary ammonium salts (series II) and (iii) halomethylated choline analogs (series III). Assessments of their in vitro cytotoxicity in human promonocytic cells U-937 and antileishmanial activity in axenic amastigotes of L. (Viannia) panamensis (M/HOM/87/UA140-pIR-eGFP) were carried out using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) micromethod. Antileishmanial activity was also tested in intracellular amastigotes of L. (V) panamensis using flow cytometry. High toxicity for human U937 cells was found with most of the compounds, which exhibited Lethal Concentration 50 (LC50) values in the range of 9 to 46 µg/mL. Most of the compounds evidenced antileishmanial activity. In axenic amastigotes, the antileishmanial activity varied from 14 to 57 µg/mL, while in intracellular amastigotes their activity varied from 17 to 50 µg/mL. N-Chloromethyl-N,N-dimethyl-N-(4,4-diphenylbut-3-en-1-yl)ammonium iodide (1a), N-iodomethyl-N,N-dimethyl-N-(4,4-diphenylbut-3-en-1-yl)ammonium iodide (2a), N,N,N-trimethyl-N-(4,4-diphenylbut-3-en-1-yl)ammonium iodide (3a) and N,N,N-trimethyl-N-(5,5-diphenylpent-4-en-1-yl)ammonium iodide (3b) turned out to be the most active compounds against intracellular amastigotes of L. (V) panamensis, with EC50 values varying between 24.7 for compound 3b and 38.4 µg/mL for compound 1a. Thus, these compounds represents new "hits" in the development of leishmanicidal drugs.


Assuntos
Compostos de Amônio/química , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Sais/química , Compostos de Amônio/síntese química , Compostos de Amônio/farmacologia , Antiprotozoários/síntese química , Antiprotozoários/química , Antiprotozoários/farmacologia , Humanos , Leishmania/patogenicidade , Leishmaniose/parasitologia , Estrutura Molecular , Compostos de Amônio Quaternário/síntese química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Sais/síntese química , Sais/farmacologia , Relação Estrutura-Atividade , Células U937
12.
Antimicrob Agents Chemother ; 59(9): 5804-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26169411

RESUMO

An evaluation of the leishmanicidal activity in vitro and in vivo of hypericin, an expanded-spectrum photosensitizer found in Hypericum perforatum, is presented. Hypericin was evaluated against intracellular amastigotes in vitro of Leishmania (Viannia) panamensis. A topical formulation containing 0.5% hypericin was developed and assayed in vivo in a hamster model of cutaneous leishmaniasis. Results demonstrate that hypericin induces a significant antiamastigote effect in vitro against L. panamensis by decreasing the number of parasites inside infected cells. The topical formulation of 0.5% hypericin allows healing of L. panamensis-induced lesions upon a topical application of 40 mg/day plus visible-light irradiation (5 J/cm(2), 15 min), twice a week for 3 weeks.


Assuntos
Leishmaniose Cutânea/tratamento farmacológico , Perileno/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Antracenos , Linhagem Celular , Cricetinae , Humanos , Leishmania/efeitos dos fármacos , Leishmania/patogenicidade , Leishmaniose Cutânea/terapia , Perileno/uso terapêutico , Células U937 , Cicatrização/efeitos dos fármacos
13.
Cochrane Database Syst Rev ; (8): CD008736, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26246011

RESUMO

BACKGROUND: Leishmaniasis is caused by the Leishmania parasite, and transmitted by infected phlebotomine sandflies. Of the two distinct clinical syndromes, cutaneous leishmaniasis (CL) affects the skin and mucous membranes, and visceral leishmaniasis (VL) affects internal organs. Approaches to prevent transmission include vector control by reducing human contact with infected sandflies, and reservoir control, by reducing the number of infected animals. OBJECTIVES: To assess the effects of vector and reservoir control interventions for cutaneous and for visceral leishmaniasis. SEARCH METHODS: We searched the following databases to 13 January 2015: Cochrane Infectious Diseases Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS and WHOLIS, Web of Science, and RePORTER. We also searched trials registers for ongoing trials. SELECTION CRITERIA: Randomized controlled trials (RCTs) evaluating the effects of vector and reservoir control interventions in leishmaniasis-endemic regions. DATA COLLECTION AND ANALYSIS: Two review authors independently searched for trials and extracted data from included RCTs. We resolved any disagreements by discussion with a third review author. We assessed the quality of the evidence using the GRADE approach. MAIN RESULTS: We included 14 RCTs that evaluated a range of interventions across different settings. The study methods were generally poorly described, and consequently all included trials were judged to be at high or unclear risk of selection and reporting bias. Only seven trials reported clinical outcome data which limits our ability to make broad generalizations to different epidemiological settings and cultures. Cutaneous leishmaniasisOne four-arm RCT from Afghanistan compared indoor residual spraying (IRS), insecticide-treated bednets (ITNs), and insecticide-treated bedsheets, with no intervention. Over 15 months follow-up, all three insecticide-based interventions had a lower incidence of CL than the control area (IRS: risk ratio (RR) 0.61, 95% confidence interval (CI) 0.38 to 0.97, 2892 participants, moderate quality evidence; ITNs: RR 0.32, 95% CI 0.18 to 0.56, 2954 participants, low quality evidence; ITS: RR 0.34, 95% CI 0.20 to 0.57, 2784 participants, low quality evidence). No difference was detected between the three interventions (low quality evidence). One additional trial of ITNs from Iran was underpowered to show a difference.Insecticide treated curtains were compared with no intervention in one RCT from Venezuela, where there were no CL episodes in the intervention areas over 12 months follow-up compared to 142 in control areas (RR 0.00, 95% CI 0.00 to 0.49, one trial, 2938 participants, low quality evidence).Personal protection using insecticide treated clothing was evaluated by two RCTs in soldiers, but the trials were underpowered to reliably detect effects on the incidence of CL (RR 0.40, 95% CI 0.13 to 1.20, two trials, 558 participants, low quality evidence). Visceral leishmaniasisIn a single RCT of ITNs versus no intervention from India and Nepal, the incidence of VL was low in both groups and no difference was detected (RR 0.99, 95% CI 0.46 to 2.15, one trial, 19,810 participants, moderate quality evidence).Two trials from Brazil evaluated the effects of culling infected dogs compared to no intervention or IRS. Although they report a reduction in seroconversion over 18 months follow-up, they did not measure or report effects on clinical disease. AUTHORS' CONCLUSIONS: Using insecticides to reduce phlebotomine sandfly numbers may be effective at reducing the incidence of CL, but there is insufficient evidence from trials to know whether it is better to spray the internal walls of houses or to treat bednets, curtains, bedsheets or clothing.


Assuntos
Reservatórios de Doenças/parasitologia , Vetores de Doenças , Inseticidas , Leishmaniose Cutânea/prevenção & controle , Leishmaniose Visceral/prevenção & controle , Abate de Animais , Animais , Vestuário , Doenças do Cão/prevenção & controle , Cães , Utensílios Domésticos , Humanos , Mosquiteiros Tratados com Inseticida , Leishmaniose Cutânea/veterinária , Leishmaniose Visceral/veterinária , Densidade Demográfica , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Molecules ; 19(9): 13251-66, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-25170948

RESUMO

Twelve hybrids derived from triclosan were obtained via Williamson etherification of O-triclosan alkyl bromide plus chalcone and O-coumarin or O-chromone alkyl bromide plus triclosan, respectively. Structures of the products were elucidated by spectroscopic analysis. The synthesized compounds were evaluated for antileishmanial activity against L. (V) panamensis amastigotes. Cytotoxic activity was also evaluated against mammalian U-937 cells. Compounds 7-9 and 17, were active against Leishmania parasites (EC50=9.4; 10.2; 13.5 and 27.5 µg/mL, respectively) and showed no toxicity toward mammalian cells (>200 µg/mL). They are potential candidates for antileishmanial drug development. Compounds 25-27, were active and cytotoxic. Further studies using other cell types are needed in order to discriminate whether the toxicity shown by these compounds is against tumor or non-tumor cells. The results indicate that compounds containing small alkyl chains show better selectivity indices. Moreover, Michael acceptor moieties may modify both the leishmanicidal activity and cytotoxicity. Further studies are required to evaluate if the in vitro activity against Leishmania panamensis demonstrated here is also observed in vivo.


Assuntos
Antiprotozoários/farmacologia , Chalconas/farmacologia , Cumarínicos/farmacologia , Leishmania/efeitos dos fármacos , Triclosan/análogos & derivados , Triclosan/farmacologia , Antiprotozoários/síntese química , Linhagem Celular Tumoral , Chalconas/síntese química , Cumarínicos/síntese química , Avaliação Pré-Clínica de Medicamentos , Humanos , Concentração Inibidora 50 , Leishmaniose/tratamento farmacológico , Triclosan/síntese química
15.
J Med Entomol ; 60(3): 527-534, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37043628

RESUMO

The community structure of sand flies indicates the level of adaptation of vector species in a region, and in the context of vector management and control, this information allows for identifying the potential risks of pathogen transmission. This study aimed to analyze sand fly diversity and spatial-temporal distribution in an endemic area of cutaneous leishmaniasis. The study was carried out in the Carrizales hamlet (Caldas), between September 2019 and October 2021. The monthly distribution of sand fly species was evaluated through collections with CDC traps. Shannon and evenness indices were calculated and used to compare species frequencies at each house. The association between climatic variables and the frequency of sand flies was evaluated using Spearman's correlation. A total of 6,265 females and 1,958 males belonging to 23 species were found. Low diversity and evenness were observed, with the dominance of Nyssomyia yuilli yuilli (Young & Porter). Ecological and diversity indices did not reveal differences between the houses. The sand fly community was composed of 3 dominant species, Ny. yuilli yuilli, Psychodopygus ayrozai (Barretto & Coutinho), and Ps. panamensis (Shannon), representing 75.8% of the total catches. No statistical association was found between the absolute frequency of sand flies, rainfall, and temperature. The results show one dominant species, this fact has epidemiological relevance since density influences parasite-vector contact. The high densities of sand flies recorded in peri- and intradomiciliary areas highlight the necessity of periodic monitoring of vector populations and control activities to reduce the risk of Leishmania transmission in this endemic area.


Assuntos
Leishmaniose Cutânea , Phlebotomus , Psychodidae , Masculino , Feminino , Animais , Colômbia/epidemiologia , Insetos Vetores , Leishmaniose Cutânea/epidemiologia
16.
Biomedica ; 42(4): 602-610, 2022 12 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36511677

RESUMO

INTRODUCTION: The use of technological resources to support processes in health systems has generated robust, interoperable and dynamic platforms. In the case of institutions working with neglected tropical diseases (NTD), there is a need for NTD-specific customizations. OBJECTIVES: To establish a medical records platform, specialized for NTD, which would facilitate the analysis of treatment evolution in patients, as well as generate more accurate data about various clinical aspects. MATERIALS AND METHODS: Here we developed a customized electronic medical record system based on OpenMRS for multiple NTDs. A set of forms and functionalities was developed under the OpenMRS guidelines, using shared community modules. RESULTS: All the customized information was packaged in a distribution called NTD Health. The platform is web-based and can be upgraded and improved by users without technological barriers. CONCLUSIONS: The EMR system can become a useful tool for other institutions to improve their health practices as well as the quality of life for NTD patients, simplifying the customization of healthcare systems able to interoperate with other platforms.


Introducción. El uso de recursos tecnológicos destinados a apoyar procesos en los sistemas de salud ha generado plataformas sólidas, interoperables y dinámicas. En el caso de las instituciones que trabajan con enfermedades tropicales desatendidas, existe la necesidad de personalizaciones específicas en las herramientas de uso médico. Objetivos. Establecer una plataforma para historias clínicas especializada en enfermedades tropicales desatendidas, con el fin de facilitar el análisis de la evolución del tratamiento de los pacientes, además de generar datos más precisos sobre diversos aspectos clínicos. Materiales y métodos. Se compiló un conjunto de requisitos para implementar formularios, conceptos y funcionalidades que permitan incluir enfermedades tropicales desatendidas. Se utilizó una distribución de OpenMRS (versión 2.3) como referencia para construir la plataforma, siguiendo las pautas recomendadas y módulos compartidos por la comunidad. Resultados. Toda la información personalizada se implementó en una plataforma llamada NTD Health, la cual se encuentra almacenada en la web y los usuarios pueden actualizarla y mejorarla sin barreras tecnológicas. Conclusiones. El sistema de historias clínicas electrónicas puede convertirse en una herramienta útil para que otras instituciones mejoren sus prácticas en salud, así como la calidad de vida de los pacientes con enfermedades tropicales desatendidas, simplificando la personalización de los sistemas de salud capaces de interoperar con otras plataformas.


Assuntos
Registros Eletrônicos de Saúde , Qualidade de Vida , Humanos , Doenças Negligenciadas
17.
Pharmaceuticals (Basel) ; 15(7)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35890075

RESUMO

Leishmaniasis may occur in three different clinical forms, namely, visceral, mucocutaneous and cutaneous, which are caused by different species of trypanosomatid protozoans of the genus Leishmania. Pentavalent antimonials are the leading treatment for cutaneous leishmaniasis despite the hepatic, renal, and cardiac toxicity. In addition, the response of some Leishmania species to pentavalent antimonials is increasingly poorer, and therefore new and more potent therapeutic alternatives are needed. Arnica montana L., Asteraceae, is a traditional medicinal plant of Europe and preparations of its flowers are commonly used externally to treat disorders of the musculoskeletal system as well as superficial inflammatory conditions. Previous studies have shown that Arnica tincture (AT), an ethanolic extract prepared from the flowerheads of Arnica montana as well as isolated Arnica sesquiterpene lactones (STLs) have antileishmanial activity in vitro against L. donovani and L. infantum, as well as in vivo against L. braziliensis. In this work, we studied the in vitro cytotoxicity and antileishmanial activity of AT and STLs against both L. braziliensis and L. tropica. The in vivo therapeutic effect of AT was studied in hamsters with cutaneous Leishmaniasis (CL) caused by experimental infection with L. braziliensis and L. tropica. Furthermore, various semisolid Arnica preparations were also evaluated against L. braziliensis. The STLs and the AT possess a very high in vitro activity against both Leishmania species with median effective concentrations (EC50) ranging from 1.9 to 5.9 µg/mL. The AT was not cytotoxic for human tissue macrophages, skin fibroblasts, and hepatic cells. The therapeutic response of hamsters infected with L. braziliensis to the topical treatment with AT was 87.5% at a dose of 19.2 µg STL/2× day/60 d, 72.7% at doses of 19.2 µg STL/1× d/60 d and 67% at a dose of 38.4 µg STL/2× d/60 d. In turn, the therapeutic response in hamsters infected with L. tropica was 100% when treated at a dose of 19.2 µg STL/2× day/60 d and 71% at a dose of 38.4 µg STL/2× d/60 d. On the other hand, the effectiveness of treatment with glucantime administered intralesionally at a dose of 200 mg/every three days for 30 days was 62.5% for L. braziliensis and 37.5% for L. tropica infection. These results are promising and encourage the implementation of clinical trials with AT in CL patients as a first step to using AT as a drug against CL.

18.
Lancet Child Adolesc Health ; 6(2): 86-95, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34871570

RESUMO

BACKGROUND: Single-dose tafenoquine 300 mg is approved for Plasmodium vivax malaria relapse prevention in patients at least 16 years old. We aimed to determine appropriate oral tafenoquine paediatric dosing regimens, including a dispersible formulation, and evaluated tafenoquine efficacy and safety in children infected with P vivax. METHODS: This open-label, single-arm, non-comparative, multicentre, pharmacokinetic bridging, phase 2 study enrolled children (2-15 years) who weighed 5 kg or more, with glucose-6-phosphate dehydrogenase activity more than 70% of the local population median, and P vivax malaria infection, from three community health centres in Vietnam and one in Colombia. Patients received 3-day chloroquine plus oral single-dose tafenoquine as dispersible tablets (50 mg) or film-coated tablets (150 mg). Dosing groups were assigned by body weight, predicted to achieve similar median exposures as the approved 300 mg dose for adults: patients who weighed 5 kg or more to 10 kg received 50 mg, those who weighed more than 10 to 20 kg received 100 or 150 mg, those who weighed more than 20 to 35 kg received 200 mg, and patients who weighed more than 35 kg received 300 mg. Population pharmacokinetic analysis was done to develop a paediatric population pharmacokinetic model. The primary outcome was the tafenoquine area under the concentration-time curve extrapolated to infinity (AUC[0-∞]) by patient body weight in the pharmacokinetic population (all patients who received tafenoquine with at least one valid pharmacokinetic sample) estimated from a paediatric population pharmacokinetic model. A key prespecified secondary outcome was 4-month recurrence-free efficacy. This trial is registered with ClinicalTrials.gov, NCT02563496. FINDINGS: Between Feb 6, 2017, and Feb 17, 2020, 60 patients were enrolled into the study: 14 (23%) received tafenoquine 100 mg, five (8%) 150 mg, 22 (36%) 200 mg, and 19 (32%) 300 mg. The paediatric population pharmacokinetic model predicted adequate tafenoquine exposure at all doses. The predicted median AUC(0-∞) was 73·8 (90% prediction interval [PI] 46·9-117·0) µg × h/mL with the 50 mg dose for patients who weighed 5 kg or more to 10 kg, 87·5 (55·4-139·0) µg × h/mL with the 100 mg dose for body weight more than 10 to 20 kg, 110·7 (70·9-174·0) µg × h/mL with the 200 mg dose for body weight more than 20 to 35 kg, and 85·7 (50·6-151·0) µg × h/mL with the 300 mg dose for body weight more than 35 kg. 4-month recurrence-free efficacy was 94·7% (95% CI 84·6-98·3). Adverse events were consistent with previous studies, except for the seven (12%) of 60 patients who had post-dose vomiting or spitting with the 50 mg dispersed tablet. Following mitigation strategies, there were no additional occurrences of this adverse event. There were no deaths during the study. INTERPRETATION: For the prevention of P vivax relapse in children, single-dose tafenoquine, including a dispersible formulation, had exposure, safety, and efficacy consistent with observations in adolescents and adults, notwithstanding post-dose vomiting. FUNDING: GlaxoSmithKline and Medicines for Malaria Venture. TRANSLATIONS: For the Vietnamese and Spanish translations of the abstract see Supplementary Materials section.


Assuntos
Aminoquinolinas/administração & dosagem , Aminoquinolinas/farmacocinética , Aminoquinolinas/uso terapêutico , Antimaláricos/administração & dosagem , Antimaláricos/farmacocinética , Antimaláricos/uso terapêutico , Malária Vivax/tratamento farmacológico , Adolescente , Área Sob a Curva , Criança , Pré-Escolar , Cloroquina/administração & dosagem , Feminino , Humanos , Masculino , Recidiva , Prevenção Secundária , Comprimidos
19.
Commun Biol ; 5(1): 1411, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36564617

RESUMO

Traditionally, patient travel history has been used to distinguish imported from autochthonous malaria cases, but the dormant liver stages of Plasmodium vivax confound this approach. Molecular tools offer an alternative method to identify, and map imported cases. Using machine learning approaches incorporating hierarchical fixation index and decision tree analyses applied to 799 P. vivax genomes from 21 countries, we identified 33-SNP, 50-SNP and 55-SNP barcodes (GEO33, GEO50 and GEO55), with high capacity to predict the infection's country of origin. The Matthews correlation coefficient (MCC) for an existing, commonly applied 38-SNP barcode (BR38) exceeded 0.80 in 62% countries. The GEO panels outperformed BR38, with median MCCs > 0.80 in 90% countries at GEO33, and 95% at GEO50 and GEO55. An online, open-access, likelihood-based classifier framework was established to support data analysis (vivaxGEN-geo). The SNP selection and classifier methods can be readily amended for other use cases to support malaria control programs.


Assuntos
Malária Vivax , Malária , Humanos , Malária Vivax/diagnóstico , Malária Vivax/genética , Funções Verossimilhança , Plasmodium vivax/genética , Internet
20.
Antimicrob Agents Chemother ; 55(10): 4755-64, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21788471

RESUMO

Carbaporphyrin ketals are porphyrinoid compounds in which a pyrrole ring of a typical porphyrin macrocycle has been replaced by a ketal-substituted indene ring. It was recently demonstrated that these compounds are effective in vitro against Leishmania tarentolae. Their in vitro effectiveness is increased when they are exposed to visible light; they act as photosensitizers capable of mediating the production of reactive oxygen species (ROS). Following on this evidence, the effectiveness and cytotoxicity of the dimethyl and diethyl carbaporphyrin ketals (CKOMe and CKOEt, respectively) were determined in vitro using pathogenic Leishmania species with and without exposure to visible light (2 and 4 h). The effectiveness against various pathogenic Leishmania species was determined to be in a micromolar range. Additionally, the effect of encapsulating the carbaporphyrin ketals in liposome formulations was tested. Liposomal delivery diminished their toxicity, while the effectiveness was enhanced upon exposure to visible light (photodynamic effect). The cytotoxicity levels for human U937 cells and hamster peritoneal macrophages were in the ranges of 0.3 to 9 µM and 7 to 330 µM, respectively. When tested in vivo, using a hamster (Mesocricetus auratus) model of cutaneous leishmaniasis, CKOMe was active even in the dark, suggesting that the compound, once metabolized in the animal tissue, produces an active ingredient that does not seem to be photosensitive. Reduction in lesion size, histopathologic analyses, and smears confirmed the in vivo effectiveness of the compound, since the parasitic load was diminished without noticeable toxic effects.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Fotoquimioterapia , Animais , Antiprotozoários/administração & dosagem , Antiprotozoários/uso terapêutico , Antiprotozoários/toxicidade , Células Cultivadas , Cricetinae , Humanos , Leishmaniose Cutânea/parasitologia , Luz , Lipossomos , Macrófagos Peritoneais/efeitos dos fármacos , Carga Parasitária , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/farmacologia , Porfirinas/uso terapêutico , Porfirinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo
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