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1.
Anticancer Res ; 41(12): 6061-6065, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34848460

RESUMO

BACKGROUND/AIM: Antimony is a chemical element used in the therapy of parasitic diseases with a promising anticancer potential. The aim of this study was to evaluate in vitro activity of free or liposomal vesicle-packed antimony trioxide (AT or LAT) in the t(15;17)(q22;q21) translocation-positive acute promyelocytic leukemia (APL) cell line NB4. MATERIALS AND METHODS: Cytotoxicity was analysed with trypan blue exclusion, the MTT assay and neutral red exclusion assay; cell proliferation with PicoGreen®; and reactive oxygen species (ROS) production with DCFDA. RESULTS: Liposomal particles did not change the pH of the cell culture medium and entered the cells. Both formulations resulted in a time- and concentration-dependent cytotoxicity and production of ROS. LAT showed higher toxicity at lower concentrations compared to AT. CONCLUSION: LAT may be used to decrease drug dosage and maintain high anti-tumoral effects on APL cells.


Assuntos
Antimônio/administração & dosagem , Antimônio/farmacologia , Lipossomos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos , Humanos , Leucemia Promielocítica Aguda , Sistemas de Liberação de Fármacos por Nanopartículas , Espécies Reativas de Oxigênio/metabolismo
2.
Toxicol In Vitro ; 71: 105064, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33279584

RESUMO

Gallium antimonide (GaSb) is a group III-V compound semiconductor with a comparatively narrow band gap energy (0.73 eV at 300 K) that allows efficient operation in the near-infrared region. This property may be useful in developing new biomedical instruments such as epidermal optoelectronic devices. The present study investigated the absorption of GaSb in pig skin in vitro for 24 h using Franz cells. A donor solution was prepared by soaking GaSb thin films in synthetic sweat. The results showed that both gallium and antimony penetrated the skin, and permeation and resorption occurred for gallium. Histopathological findings showed no inflammatory responses in pig skin exposed to GaSb for 24 h. Cytotoxicity was significantly elevated after 3 and 7 days, and pro-inflammatory cytokines and IL-8 levels were low after 1 and 3 days but elevated 7 days following the direct culturing of human dermal fibroblasts (HDF) on GaSb thin films. These results demonstrate that the short-term cytotoxicity and pro-inflammatory effect of GaSb on HDF were relatively low.


Assuntos
Antimônio/administração & dosagem , Fibroblastos/efeitos dos fármacos , Gálio/administração & dosagem , Semicondutores , Absorção Cutânea , Pele/metabolismo , Animais , Antimônio/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Difusão , Fibroblastos/metabolismo , Gálio/toxicidade , Humanos , Interleucina-8/metabolismo , Pele/citologia , Suínos
3.
PLoS Negl Trop Dis ; 14(2): e0008050, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32109251

RESUMO

Cutaneous leishmaniasis (CL) affects the lives of 0.7-1 million people every year causing lesions that take months to heal. These lesions can result in disfiguring scars with psychological, social and economic consequences. Antimonials are the first line of therapy for CL, however the treatment is lengthy and linked to significant toxicities; further, its efficacy is variable and resistant parasites are emerging. Shorter or lower dose antimonial treatment regimens, which would decrease the risk of adverse events and improve patient compliance, have shown reduced efficacy and further increase the risk emergence of antimonial-resistant strains. The progression of lesions in CL is partly determined by the immune response it elicits, and previous studies showed that administration of immunomodulatory type D CpG ODNs, magnifies the immune response to Leishmania and reduces lesion severity in nonhuman primates (NHP) challenged with Leishmania major or Leishmania amazonensis. Here we explored whether the addition of a single dose of immunomodulating CpG ODN D35 augments the efficacy of a short-course, low-dose pentavalent antimonial treatment regimen. Results show that macaques treated with D35 plus 5mg/kg sodium stibogluconate (SbV) for 10 days had smaller lesions and reduced time to re-epithelization after infection with Leishmania major. No toxicities were evident during the studies, even at doses of D35 10 times higher than those used in treatment. Critically, pentavalent antimonial treatment did not modify the ability of D35 to induce type I IFNs. The findings support the efficacy of D35 as adjuvant therapy for shorter, low dose pentavalent antimonial treatment.


Assuntos
Leishmaniose Cutânea/tratamento farmacológico , Oligodesoxirribonucleotídeos/classificação , Oligodesoxirribonucleotídeos/uso terapêutico , Animais , Antimônio/administração & dosagem , Antimônio/farmacologia , Linhagem Celular , Quimiocinas/genética , Quimiocinas/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Humanos , Leishmania major , Leishmaniose Cutânea/parasitologia , Leucócitos Mononucleares/efeitos dos fármacos , Macaca fascicularis , Masculino , Oligodesoxirribonucleotídeos/administração & dosagem
4.
Photodiagnosis Photodyn Ther ; 28: 210-215, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31454712

RESUMO

BACKGROUND: In the Americas, one of the main causative species of cutaneous leishmaniasis is Leishmania (Leishmania) amazonensis. The systemic antimonials remain the most largely used option for disease control. However, this drug has significant toxicity. The development of new alternative therapies, including the identification of effective drugs for topical treatment of cutaneous leishmaniasis, is of utmost interest. In this sense, photodynamic therapy emerges as a new strategy. The aim of this study was to develop the chloroaluminum phthalocyanine-loaded liposome, characterize it, and evaluate its stability and efficacy in the topical treatment of cutaneous leishmaniasis caused by L. (L.) amazonensis. METHODS: Liposomes composed of egg phosphatidylcholine were prepared by Bangham's method. Storage stability of phthalocyanine-loaded liposomes was evaluated at 30 and 60 days after preparation. For the in vivo evaluation, the animals were infected with L. (L.) amazonensis and divided into groups: chloroaluminium phthalocyanine-loaded liposome, blank liposome, meglumine antimoniate (200 mgSb+5/Kg/day), and control. The lesion size was determined weekly after the beginning of the treatment. Upon completion, parasites were recovered from the skin lesion and spleen and evaluated by limiting dilution assay. RESULTS: Chloroaluminum phthalocyanine-loaded liposomes were stable and showed adequate characteristics for topical administration. The topical chloroaluminum phthalocyanine-loaded liposome was as effective as systemic pentavalent antimony in reducing the parasitic load in the lesion and spleen in infected animals. CONCLUSIONS: The present study showed that photodynamic therapy with chloroaluminum phthalocyanine-loaded liposomes is a promising strategy for the treatment of American cutaneous leishmaniasis caused by L. (L.) amazonensis.


Assuntos
Antimônio/administração & dosagem , Indóis/administração & dosagem , Leishmaniose Cutânea/tratamento farmacológico , Compostos Organometálicos/administração & dosagem , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Administração Tópica , Animais , Lipossomos , Mesocricetus , Camundongos Endogâmicos BALB C , Baço/parasitologia
5.
Parasitol Res ; 118(10): 3077-3084, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401656

RESUMO

Clinically available drugs for mucocutaneous and cutaneous leishmaniases (CL) include mainly pentavalent antimony (Sb(V)) complexes, liposomal amphotericin B, and miltefosine (HePC). However, they present at least one of the following limitations: long-term parenteral administration through repeated doses, severe side effects, drug resistance, and high cost. HePC is the only oral drug available, but the appearance of resistance has resulted in changes of its use from monotherapy to combination therapy. Amphiphilic Sb(V) complexes, such as SbL8 obtained from reaction of Sb(V) with N-octanoyl-N-methylglucamide, were recently found to be orally active against experimental CL. The property of SbL8 to self-assemble in aqueous solution, forming nanostructures, led us to investigate the incorporation of HePC into SbL8 nanoassemblies and the therapeutic efficacy of SbL8/HePC nanoformulation by oral route in a murine model of CL. HePC incorporation into the SbL8 nanosystem was evidenced by using a fluorescent analog of HePC. The antileishmanial activity of SbL8/HePC nanoassemblies was evaluated after daily oral administration for 30 days in Leishmania amazonensis-infected BALB/c mice, in comparison with monotherapies (SbL8 or HePC) and saline control. All the treatments resulted in significant reduction in the lesion size growth, when compared with control. Strikingly, only SbL8/HePC nanoassemblies promoted a significant decrease of the parasite burden in the lesion. This work establishes the therapeutic benefit of SbL8/HePC association by oral route in a CL model and constitutes an important step towards the development of new orally active drug combination.


Assuntos
Antimônio/química , Antiprotozoários/administração & dosagem , Leishmania mexicana/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Fosforilcolina/análogos & derivados , Administração Oral , Animais , Antimônio/administração & dosagem , Antiprotozoários/química , Modelos Animais de Doenças , Feminino , Leishmaniose Cutânea/parasitologia , Camundongos Endogâmicos BALB C , Nanopartículas/administração & dosagem , Nanopartículas/química , Fosforilcolina/administração & dosagem , Fosforilcolina/química
6.
Parasitol Res ; 118(9): 2669-2678, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31278518

RESUMO

The aims of this study were to produce biogenic antimony sulfide nanoparticles (NPs) using Serratia marcescens (S. marcescens) and investigate the potential anti-leishmanial effects of these NPs on Leishmania major (L. major) (MRHO/IR/75/ER) in both in vitro and in vivo experiments. Biogenic antimony sulfide NPs were synthesized through intracellular biological methods using S. marcescens. The efficiency of various concentrations of antimony sulfide NPs was assessed using in vitro experiments on amastigotes of L. major at various times post-infection. In vivo experiments were carried out in BALB/c mice inoculated subcutaneously with 2 × 106L. major promastigotes (MHROM/IR/75/ER) and treated with antimony sulfide NPs (70 µg/mL, tropically), meglumine antimoniate (glucantime) as positive control and sterile phosphate-buffered saline (PBS, pH 7.4) as vehicle control. Results of in vitro experiments revealed that the anti-leishmanial activity increased when the antimony sulfide NPs concentration increased. The IC50 (50% inhibitory concentration) of antimony sulfide NPs against amastigotes was calculated as 62.5 µg/mL. In in vivo experiments, the average size of lesions significantly decreased to 8.6 ± 2.7 mm2 in mice inoculated with L. major promastigotes and treated with antimony sulfide NPs, compared with that in the negative control group (P = 0.015). Furthermore, results showed that antimony sulfide NPs significantly decreased the parasite load in the test group, compared with the negative control group (P = 0.001). Various concentrations of antimony sulfide NPs showed a great anti-leishmanial efficiency against L. major (MRHO/IR/75/ER), with the greatest efficiency shown by a concentration of 62.5 µg/mL in in vitro and in vivo experiments.


Assuntos
Antimônio/administração & dosagem , Antiprotozoários/administração & dosagem , Antipruriginosos/administração & dosagem , Leishmania major/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Nanopartículas/administração & dosagem , Sulfetos/administração & dosagem , Animais , Humanos , Concentração Inibidora 50 , Leishmania major/fisiologia , Leishmaniose Cutânea/parasitologia , Camundongos , Camundongos Endogâmicos BALB C
7.
Arch Dermatol Res ; 311(1): 9-17, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30390113

RESUMO

Pentavalent antimonials remain the treatment of choice for all the clinical forms of leishmaniasis. The increasing rates of antimony resistance are becoming a serious health problem in treatment of anthroponotic cutaneous leishmaniasis (ACL). Accordingly, unraveling molecular markers is crucial for improving medication strategies and monitoring of drug-resistant parasites. Different studies have suggested the importance of genes involved in trypanothione metabolism and drug transport. In this regard, present study was designed to investigate the RNA expression level of five genes including γ-GCS, ODC, TRYR (involved in trypanothione metabolism), AQP1 (acts in drug uptake) and MRPA (involved in sequestration of drug) in sensitive and resistant Leishmania tropica isolates. Seven antimony-resistant and seven antimony-sensitive L. tropica clinical isolates were collected from ACL patients. Drug sensitivity test was performed on the samples as well as reference strains; afterwards, gene expression analysis was performed on clinical isolates by quantitative real-time PCR. The results revealed that the average expression level of AQP1 gene was decreased (0.47-fold) in resistant isolates compared to sensitive ones whereas MRPA (2.45), γ-GCS (2.1) and TRYR (1.97) was upregulated in resistant isolates. The average expression of ODC (1.24-fold) gene was not different significantly between sensitive and resistant isolates. Our findings suggest that AQP1, MRPA, GSH1 and TRYR can be considered as potential molecular markers for screening of antimony resistance in some L. tropica clinical isolates.


Assuntos
Antimônio/farmacologia , Resistência a Medicamentos/fisiologia , Glutationa/análogos & derivados , Leishmania tropica/efeitos dos fármacos , Leishmania tropica/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Espermidina/análogos & derivados , Antimônio/administração & dosagem , Antiprotozoários/farmacologia , Transporte Biológico , Relação Dose-Resposta a Droga , Resistência a Medicamentos/genética , Glutationa/metabolismo , Leishmania tropica/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Espermidina/metabolismo , Transcriptoma
8.
Biol Trace Elem Res ; 186(1): 199-207, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29520725

RESUMO

Groundwater used for drinking has been contaminated with naturally occurring inorganic arsenic and other metals, and metal-contaminated drinking water is the biggest threat to public health in Bangladesh. Toxic metals present in the drinking water have a strong relationship with chronic diseases in humans. Antimony (Sb), a naturally occurring metal, has been reported to be present in the drinking water along with other heavy metals in Bangladesh. Although Sb is present in the environment, very little attention has been given to the toxic effects of Sb. The present study was designed to investigate the in vivo effects of Sb on neurobehavioral changes like anxiety, learning and memory impairment, and blood indices related to organ dysfunction. Mice exposed to antimony potassium-tartrate hydrate (Sb) (10 mg/kg body weight) significantly (p < 0.05) decreased the time spent in open arms while increased the time spent in closed arms compared to the control mice in elevated plus maze. The mean latency time of control group to find the platform decreased (p < 0.05) significantly during 7 days learning as compared to Sb-treated group in Morris water maze test, and Sb-exposed group spent significantly (p < 0.05) less time in the desired quadrant as compared to the control group in probe trial. Sb treatment also significantly altered blood indices related to liver and kidney dysfunction. Additionally, Sb-induced biochemical alterations were associated with significant perturbations in histological architecture of liver and kidney of Sb-exposed mice. These data suggest that Sb has a toxic effect on neurobehavioral and biochemical changes in mice.


Assuntos
Antimônio/toxicidade , Comportamento Animal/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/sangue , Animais , Antimônio/administração & dosagem , Rim/metabolismo , Fígado/metabolismo , Masculino , Transtornos da Memória/induzido quimicamente , Camundongos
9.
Expert Rev Anti Infect Ther ; 16(3): 219-225, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29411659

RESUMO

INTRODUCTION: Mucosal Leishmaniasis (ML) is a difficult to treat and severe form of Leishmaniasis. In general, more than 40% of subjects with ML have therapeutic failure upon the use of pentavalent antimony (Sbv) at 20mg/kg/day during 30 days. Additionally, Sbv is a toxic drug that requires parenteral administration, and many patients will need several courses to be cured. In cases that cannot be treated or cured by Sbv, the alternative is amphotericin B, another toxic and parenteral drug. As a consequence, many ML patients will be cured only after years of disease and may present several morbidities due to the aggressiveness of the disease or toxicity related to the treatment. Areas covered: We aimed to review clinical trials with Miltefosine or Sbv associated with pentoxifylline in the treatment of ML. Expert commentary: There are few studies to define more effective and safer therapy in mucosal disease caused by Leishmania, with an urgent need to supporting and funding well designed trials. Miltefosine monotherapy, as well as pentoxifylline combined with Sbv are promising therapeutic approaches to increase the cure rate of this neglected disease.


Assuntos
Antimônio/administração & dosagem , Leishmaniose Mucocutânea/tratamento farmacológico , Pentoxifilina/administração & dosagem , Fosforilcolina/análogos & derivados , Animais , Antimônio/efeitos adversos , Antiprotozoários/administração & dosagem , Antiprotozoários/efeitos adversos , Quimioterapia Combinada , Humanos , Leishmaniose Mucocutânea/microbiologia , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/microbiologia , Pentoxifilina/efeitos adversos , Fosforilcolina/administração & dosagem , Fosforilcolina/efeitos adversos , Resultado do Tratamento
10.
J Infect Dis ; 217(5): 840-850, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29216363

RESUMO

Background: Early cutaneous leishmaniasis (ECL) is characterized by a nonulcerated papular lesion and illness duration less than 30 days. Approximately 4 weeks later, the cutaneous leishmaniasis (CL) ulcers appear. We were surprised to find that failure after antimony therapy (Sb5) is higher in ECL than CL. We hypothesize that the inflammatory response in ECL patients may increase during Sb5 therapy, which leads to treatment failure. Methods: A cohort of 44 ECL patients infected by Leishmania braziliensis was established to evaluate the response to Sb5 and to compare immunologic responses in ECL patients with CL and healthy subjects. Results: A hierarchical clustering based on cytokine levels showed a weak positive correlation between proinflammatory cytokine levels and those patients that failed Sb5 treatment. Although Sb5 therapy decreased interferon-γ and tumor necrosis factor levels in CL patients, we were surprised to find that an increase in these cytokines was observed in ECL patients. Moreover, interleukin (IL)-10 was less able to down-modulate immune responses in ECL. Conclusions: The enhanced production of proinflammatory cytokines, due in part to the decreased ability of IL-10 to down-modulate immune response during therapy in ECL, promotes the development and persistence of leishmania ulcer despite antimony therapy.


Assuntos
Antimônio/administração & dosagem , Antiprotozoários/administração & dosagem , Inflamação/patologia , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/patologia , Adulto , Estudos Transversais , Citocinas/sangue , Feminino , Humanos , Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Leucócitos Mononucleares/imunologia , Masculino , Prevenção Secundária , Falha de Tratamento , Adulto Jovem
11.
Arch Toxicol ; 91(12): 3823-3833, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28612261

RESUMO

Antimony is utilized in a large variety of industrial applications, leading to significant environmental and occupational exposure. Mainly based on animal experiments, the IARC and MAK Commission have classified antimony and its inorganic compounds as Group 2B or 2 carcinogens, respectively. However, the underlying mode(s) of action are still largely unknown. In the present study, we investigated the impact of non-cytotoxic up to cytotoxic concentrations of SbCl3 on DNA DSB repair and cell cycle control in HeLa S3 cells. We induced DSB by γ-irradiation and analyzed inhibitory actions of antimony on potential molecular targets of the DSB repair machinery. Antimony disturbed cell cycle control, affecting phosphorylation of Chk1. Furthermore, the repair of DSB was impaired in the presence of antimony, as monitored by pulsed-field gel electrophoresis and γH2AX foci formation of cells in G1 and G2 phase. Specifically, BRCA1 and RAD51 were identified as molecular targets. Our results point towards an interference with both non-homologous end-joining (NHEJ) and homologous recombination (HR), and inhibitory effects may be explained by interactions with critical cysteine groups; this needs to be further investigated. Altogether, the results provide further evidence for the impairment of DNA repair processes as one underlying mechanism in antimony-induced carcinogenicity.


Assuntos
Antimônio/toxicidade , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Antimônio/administração & dosagem , Proteína BRCA1/genética , Ciclo Celular/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Dano ao DNA/efeitos da radiação , Reparo do DNA por Junção de Extremidades/efeitos dos fármacos , Reparo do DNA/efeitos da radiação , Células HeLa , Recombinação Homóloga/efeitos dos fármacos , Humanos , Rad51 Recombinase/genética , Radiação Ionizante
12.
PLoS One ; 12(6): e0180530, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28662149

RESUMO

Leishmaniasis is a group of diseases caused by protozoa of Leishmania genus. The currently available treatments for this disease are expensive, present high toxicity and are associated to difficulties of healing and parasite resistance. Therefore, the development of strategies for leishmaniasis treatment is indispensable and includes reposition of existing drugs, as well as drug combination therapy. The aim of this study was to assess the nature of ketoconazole and antimony association on the cytotoxic effect against Leishmania (Leishmania) amazonensis amastigotes. The calculated mean sum of fractional 50% inhibitory concentration ([Formula: see text]ΣFIC50) was 2.54 and 1.43 for free and intracellular amastigotes, respectively, values that suggest an additive interaction between ketoconazole and antimony concerning to Leishmania toxicity only in the intramacrophage parasite form. Despite the clinical efficacy of ketoconazole-antimony combination has been shown in the literature, our study is the first to describe the nature of ketoconazole-antimony interaction against L. (L.) amazonensis amastigotes. Moreover, our results point out the need for future in vivo studies to confirm the nature of ketoconazole-antimony interaction and also to determine possible effective dosage regimens related to ketoconazole administration in association with the optimal lower dose of antimony.


Assuntos
Antimônio/farmacologia , Cetoconazol/farmacologia , Leishmania/efeitos dos fármacos , Animais , Antimônio/administração & dosagem , Sinergismo Farmacológico , Feminino , Técnicas In Vitro , Cetoconazol/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C
13.
Clin Infect Dis ; 64(1): 67-71, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27803094

RESUMO

BACKGROUND: The treatment of cutaneous leishmaniasis (CL) caused by Leishmania braziliensis in Brazil with pentavalent antimony (Sbv) is associated with a high rate of failure, up to 45% of cases. In addition, Sbv can only administered parenterally and has important toxic effect. An effective, safe, and oral treatment for CL is required. METHODS: A randomized controlled clinical trial was conducted to compare the efficacy and safety of high-dosage oral fluconazole (6.5-8.0 mg/kg/d for 28 days) versus a standard Sbv protocol (20 mg/kg/d for 20 days) for the treatment of CL in Bahia, Brazil. RESULTS: A total of 53 subjects were included in the trial; 26 were treated with Sbv, and 27 with fluconazole. Intention-to-treat analysis showed initial cure rates (2 months after treatment) of 22.2% (6 of 27) in the fluconazole and 53.8% (14 of 26) in the Sbv group (P = .04). Six months after treatment, the final cure rate remained the same in both groups, without any relapses. The frequencies of adverse effects in the Sbv and fluconazole groups were similar, 34.6% versus 37% respectively. One patient treated with fluconazole discontinued treatment owing to malaise, headache, and moderate dizziness (Common Terminology Criteria for Adverse Events grade 2). CONCLUSIONS: Oral fluconazole at a dosage of 6.5-8 mg/kg/d for 28 days should not be considered an effective treatment for CL caused by L. braziliensisClinical Trials Registration. NCT01953744.


Assuntos
Antiprotozoários/uso terapêutico , Fluconazol/uso terapêutico , Leishmania braziliensis/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Adolescente , Adulto , Antimônio/administração & dosagem , Antimônio/efeitos adversos , Antimônio/uso terapêutico , Antiprotozoários/administração & dosagem , Antiprotozoários/efeitos adversos , Brasil , Feminino , Fluconazol/administração & dosagem , Fluconazol/efeitos adversos , Humanos , Leishmania braziliensis/genética , Leishmaniose Cutânea/diagnóstico , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
14.
Am J Trop Med Hyg ; 94(4): 852-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26903605

RESUMO

A novel therapy, intralesional (IL) pentamidine, was compared to intralesional therapy with antimony (ILSb), a World Health Organization-recommended therapy, for single Bolivian Leishmania braziliensis lesions. In Study 1, 90 patients were randomized equally between three injections of ILSb over 5 days, five injections of ILSb over 11 days, and three injections of IL pentamidine (120 µg/mm(2)lesion area [ILPenta-120-3]) over 5 days. Cure rates at 6 months were 57% for ILSb-3 injections, 73% for ILSb-5 injections, and 72% for ILPenta-120-3 injections. Adverse effects were local irritation and injection-site pain-ILSb (60 patients): mild (25), moderate (4); IL pentamidine (30 patients): mild (4), moderate (3). In Study 2, 60 patients were randomized equally between five injections of ILSb and three injections of a double dose of IL pentamidine (240 µg/mm(2)[ILPenta-240-3]). In Study 2, cure rates were 67% for ILSb-5 injections and 73% for ILPenta-240-3. For three IL injections of pentamidine, efficacy was optimized at a dose of 120 µg/mm(2)lesion area. The cure rate of that regimen was similar to that for ILSb-5 injections and nonstatistically larger than that of ILSb-3 injections. IL pentamidine is an attractive alternative to ILSb on the basis of efficacy for Bolivian L. braziliensis, the threat of Sb-resistant parasites, tolerance, and patient convenience of three visits over 5 days.


Assuntos
Leishmania braziliensis/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Pentamidina/administração & dosagem , Tripanossomicidas/administração & dosagem , Adulto , Antimônio/administração & dosagem , Antimônio/uso terapêutico , Esquema de Medicação , Feminino , Humanos , Injeções Intralesionais/métodos , Masculino , Pentamidina/uso terapêutico , Resultado do Tratamento , Tripanossomicidas/uso terapêutico
15.
Clin Nucl Med ; 41(4): 319-20, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26359561

RESUMO

A 52-year-old woman diagnosed with invasive ductal carcinoma of both breasts had a chest x-ray for preoperative assessment. A striking artifact was noted by the x-ray technologist, who, as a result, became very concerned about radiation exposure from the patient. The patient had undergone bilateral sentinel lymph node injections in the nuclear medicine department with Tc-antimony trisulfite colloid just 2 hours before the chest x-ray. Radiation exposure to the x-ray technologist was determined to be similar to 8 hours of naturally occurring background radiation (∼2.96 µSv).


Assuntos
Antimônio/efeitos adversos , Neoplasias da Mama/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Compostos Radiofarmacêuticos/efeitos adversos , Compostos de Tecnécio/efeitos adversos , Antimônio/administração & dosagem , Artefatos , Feminino , Humanos , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/administração & dosagem , Compostos de Tecnécio/administração & dosagem
16.
PLoS Negl Trop Dis ; 9(10): e0004178, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26485398

RESUMO

BACKGROUND: The effectiveness of systemic antimonial (sodium stibogluconate, Pentostam, SSG) treatment versus local heat therapy (Thermomed) for cutaneous leishmaniasis was studied previously and showed similar healing rates. We hypothesized that different curative immune responses might develop with systemic and local treatment modalities. METHODS: We studied the peripheral blood immune cells in a cohort of 54 cutaneous Leishmania major subjects treated with SSG or TM. Multiparameter flow cytometry, lymphoproliferative assays and cytokine production were analyzed in order to investigate the differences in the immune responses of subjects before, on and after treatment. RESULTS: Healing cutaneous leishmaniasis lead to a significant decline in circulating T cells and NKT-like cells, accompanied by an expansion in NK cells, regardless of treatment modality. Functional changes involved decreased antigen specific CD4+ T cell proliferation (hyporesponsiveness) seen with CD8+ T cell depletion. Moreover, the healing (or healed) state was characterized by fewer circulating regulatory T cells, reduced IFN-γ production and an overall contraction in polyfunctional CD4+ T cells. CONCLUSION: Healing from cutaneous Leishmaniasis is a dynamic process that alters circulating lymphocyte populations and subsets of T, NK and NKT-like cells. Immunology of healing, through local or systemic treatments, culminated in similar changes in frequency, quality, and antigen specific responsiveness with immunomodulation possibly via a CD8+ T cell dependent mechanism. Understanding the evolving immunologic changes during healing of human leishmaniasis informs protective immune mechanisms.


Assuntos
Antimônio/administração & dosagem , Hipertermia Induzida/métodos , Leishmania major/imunologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/terapia , Adolescente , Adulto , Proliferação de Células , Estudos de Coortes , Tratamento Farmacológico/métodos , Feminino , Citometria de Fluxo , Humanos , Interferon gama/metabolismo , Leishmaniose Cutânea/parasitologia , Leucócitos Mononucleares/imunologia , Subpopulações de Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
PLoS One ; 9(8): e104055, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25105501

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) is a chronic debilitating disease endemic in tropical and subtropical areas, caused by protozoan parasites of the genus Leishmania. Annually, it is estimated the occurrence of 0.2 to 0.4 million new cases of the disease worldwide. Considering the lack of an effective vaccine the afflicted population must rely on both, an accurate diagnosis and successful treatment to combat the disease. Here we propose to evaluate the efficacy of trivalent antimonial encapsulated in conventional liposomes, in association with ascorbic acid, by monitoring its toxicity and efficacy in BALB/c mice infected with Leishmania infantum. METHODOLOGY/PRINCIPAL FINDINGS: Infected mice were subjected to single-dose treatments consisting in the administration of either free or liposome-encapsulated trivalent antimony (SbIII), in association or not with ascorbic acid. Parasite burden was assessed in the liver, spleen and bone marrow using the serial limiting dilution technique. After treatment, tissue alterations were examined by histopathology of liver, heart and kidney and confirmed by serum levels of classic biomarkers. The phenotypic profile of splenocytes was also investigated by flow cytometry. Treatment with liposome-encapsulated SbIII significantly reduced the parasite burden in the liver, spleen and bone marrow. Co-administration of ascorbic acid, with either free SbIII or its liposomal form, did not interfere with its leishmanicidal activity and promoted reduced toxicity particularly to the kidney and liver tissues. CONCLUSIONS/SIGNIFICANCE: Among the evaluated posological regimens treatment of L. infantum-infected mice with liposomal SbIII, in association with ascorbic acid, represented the best alternative as judged by its high leishmanicidal activity and absence of detectable toxic effects. Of particular importance, reduction of parasite burden in the bone marrow attested to the ability of SbIII-carrying liposomes to efficiently reach this body compartment.


Assuntos
Antimônio/efeitos adversos , Antimônio/uso terapêutico , Leishmania infantum/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Lipossomos/uso terapêutico , Animais , Antimônio/administração & dosagem , Ácido Ascórbico/administração & dosagem , Citometria de Fluxo , Imunofenotipagem , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Estatísticas não Paramétricas
18.
Molecules ; 19(5): 5478-89, 2014 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-24786687

RESUMO

Previous studies have shown that the association of the drug meglumine antimoniate (MA) with ß-cyclodextrin can improve its bioavailability by the oral route. In this work, ribose and maltose were investigated for their ability to form mixed or association complexes with MA, release MA and modulate the serum levels of Sb after oral administration in mice. Analysis of the MA/ribose composition by high performance liquid chromatography coupled to mass spectrometry (LCMS-IT-TOF) revealed the presence of mixed meglumine-Sb-ribose and Sb-ribose complexes. Analysis of the MA/maltose composition suggested the formation of MA-maltose association compounds. Circular dichroism characterization of these compositions following dilution in water at 37 °C suggested a partial and slow dissociation of the association compounds. When the MA/ribose composition was administered orally and compared to MA, the serum concentration of Sb was significantly lower after 1 h and greater after 3 h. On the other hand, the MA/maltose composition showed similar serum Sb concentration after 1 h and higher level of Sb after 3 h, when compared to MA. In conclusion, the present study has demonstrated the formation of mixed or association complexes of MA with sugars, such as maltose and ribose, which promoted sustained serum level of Sb after oral administration.


Assuntos
Antimônio/administração & dosagem , Disponibilidade Biológica , Carboidratos/administração & dosagem , Administração Oral , Animais , Antimônio/química , Carboidratos/química , Dicroísmo Circular , Ciclodextrinas , Humanos , Meglumina/administração & dosagem , Meglumina/química , Antimoniato de Meglumina , Camundongos , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/química
19.
Turk J Pediatr ; 55(4): 378-83, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24292030

RESUMO

The aim of this study was to investigate the efficacy of a 21-day schedule of liposomal amphotericin B compared to pentavalent antimony salts in the treatment of patients during a first episode of visceral leishmaniasis. In this study, 17 cases of visceral leishmaniasis admitted to Behçet Uz Children's Hospital between January 2005 and April 2012 were reviewed retrospectively. The study group was composed of 11 males (64.7%) and 6 females (35.3%). One group included 11 patients who were treated with pentavalent antimony salts, sodium stibogluconate or meglumine antimoniate, intramuscularly for 28 days. The second group was treated with amphotericin B intravenously at a dosage of 3 mg/kg on days 1-5, 10 and 21 (a cumulative dose of 21 mg/kg/day). While pentavalent antimony salts were found to increase biochemical and hematological findings, liposomal amphotericin B was responsible for rapid recovery in fever and shorter hospital stay. As a result, our study shows the advantages of both medications independent of their costs.


Assuntos
Anfotericina B/uso terapêutico , Antimônio/uso terapêutico , Leishmaniose Visceral/tratamento farmacológico , Antimônio/administração & dosagem , Antiprotozoários/uso terapêutico , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Injeções Intramusculares , Masculino , Estudos Retrospectivos , Resultado do Tratamento
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