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BACKGROUND: Our objective was to determine whether the use of two or more courses of low-dose systemic dexamethasone for extubation of ventilator-dependent preterm infants after the first week of life, as proposed in the DART study, is associated with greater neurodevelopmental harm at two years of corrected age, compared to a single course. METHODS: Retrospective review at seven level III neonatal intensive care units. Preterm infants who underwent only one course of systemic dexamethasone for extubation were grouped into DART-1; those who underwent two or more courses were grouped into DART-2. Data and outcomes of infants in DART-2 were compared with those in DART-1. RESULTS: 150 preterm infants were studied: 104 in DART-1 and 46 in DART-2. Patients in DART-2 had a lower gestational age (25 vs. 26 weeks, p = 0.031) and greater morbidity. The average dexamethasone cumulative dose for patients in DART-1 was 0.819 mg/kg, vs. 1.697 mg/kg for patients in DART-2. A total of 14 patients died. The neuromotor and neurosensory assessments at two years of corrected age revealed in the DART-2 survivors, after the multivariate analysis, a higher prevalence of cerebral palsy with functional motor class 2 (OR = 6.837; 95%CI: 1.054-44.337; p = 0.044) and ophthalmological problems requiring the use of glasses (OR = 4.157; 95%CI: 1.026-16.837; p = 0.046). CONCLUSIONS: In this cohort, the use of more than one course of systemic dexamethasone in low doses for extubation of ventilator-dependent premature infants after the first week of life was associated, at two years of corrected age, with a higher prevalence of cerebral palsy with functional motor class 2 and ophthalmological problems requiring the use of glasses.
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Paralisia Cerebral , Dexametasona , Recém-Nascido Prematuro , Humanos , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Paralisia Cerebral/epidemiologia , Recém-Nascido , Feminino , Masculino , Estudos Retrospectivos , Pré-Escolar , Prevalência , Extubação , Respiração ArtificialRESUMO
Cutaneous leishmaniasis (CL) is a neglected tropical disease. The treatment is restricted to drugs, such as meglumine antimoniate and amphotericin B, that exhibit toxic effects, high cost, long-term treatment, and limited efficacy. The development of new alternative therapies, including the identification of effective drugs for the topical and oral treatment of CL, is of great interest. In this sense, a combination of topical photodynamic therapy (PDT) with chloroaluminum phthalocyanine liposomes (Lip-ClAlPc) and the oral administration of a self-emulsifying drug delivery system containing fexinidazole (SEDDS-FEX) emerges as a new strategy. The aim of the present study was to prepare, characterize, and evaluate the efficacy of combined therapy with Lip-ClAlPc and SEDDS-FEX in the experimental treatment of Leishmania (Leishmania) major. Lip-ClAlPc and SEDDS-FEX were prepared, and the antileishmanial efficacy study was conducted with the following groups: 1. Lip-ClAlPc (0.05 mL); 2. SEDDS-FEX (50 mg/kg/day); 3. Lip-ClAlPc (0.05 mL)+SEDDS-FEX (50 mg/kg/day) combination; 4. FEX suspension (50 mg/kg/day); and 5. control (untreated). BALB/c mice received 10 sessions of topical Lip-ClAlPc on alternate days and 20 consecutive days of SEDDS-FEX or FEX oral suspension. Therapeutical efficacy was evaluated via the parasite burden (limiting-dilution assay), lesion size (mm), healing of the lesion, and histological analyses. Lip-ClAlPc and SEDDS-FEX presented physicochemical characteristics that are compatible with the administration routes used in the treatments. Lip-ClAlPc+SEDDS-FEX led to a significant reduction in the parasitic burden in the lesion and spleen when compared to the control group (p < 0.05) and the complete healing of the lesion in 43% of animals. The Lip-ClAlPc+SEDDS-FEX combination may be promising for the treatment of CL caused by L. major.
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Aim: To develop nanoemulsions (NEs) loading amphotericin B (AmB) and to evaluate the influence of different excipients on the stability and the supramolecular organization, retention and toxicity of AmB. Materials & methods: The NEs were developed from different oils, surfactants, external media and anionic lipids (disteaoryl phosphatidylglycerol [DSPG] and dioleoyl phosphatidylglycerol [DOPG]). Their impact on the size, pH, zeta potential, AmB encapsulation efficiency, AmB retention and hemolytic potential of the NEs was evaluated. Results & conclusion: The use of soybean oil (lipid matrix), Span 80 (surfactant), phosphate buffer (external phase) and DSPG or DOPG (hydrophobic ion pair) provided better NE stability, higher AmB retention within the NEs and a safer formulation profile in hemolysis tests.
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Anfotericina B , Fosfatidilgliceróis , Anfotericina B/toxicidade , Tensoativos , Antifúngicos/químicaRESUMO
INTRODUCTION: Bronchopulmonary dysplasia (BPD) is the most common complication associated with extreme prematurity. Although several criteria defining severity were developed over time, there are a few studies describing the differences in BPD phenotype and neonatal morbidities and complications between severity groups. We aimed to describe these differences in BPD patients of a neonatal intensive care unit (NICU). METHODS: We conducted an observational retrospective cohort study through a medical record review over a five-year period. Participants were newborns admitted to an NICU who were diagnosed with BPD. We performed a descriptive statistical analysis of gestational complications and the use of antenatal corticosteroid therapy, birth-related data, and complications throughout the NICU stay, as well as the respiratory support used. We also compared different severity groups across these variables. The patients were divided into severe and non-severe BPD using the severity criteria of the 2001 NICHD/NHLBI/ORD consensus workshop. RESULTS: A total of 101 newborns with BPD participated in the study and 73 had data on BPD severity. The median gestational age was 27 weeks, ranging from 23 to 32 weeks. Of these 73 newborns, 36 had mild BPD (49.3%), 10 had moderate BPD (13.7%), and 27 had severe BPD (37.0%). When comparing severe and non-severe BPD, we found that extreme prematurity, extremely low birth weight, and small size for gestational age were more frequent in the severe BPD group (p-value=0.012, p-value<0.001, and p-value=0.012, respectively). Infants with severe BPD had a longer duration of invasive ventilation than those with mild or moderate BPD (p-value<0.001). Late sepsis, necrotizing enterocolitis, severe brain injury, and retinopathy of prematurity were more frequent in severe BPD (p-value=0.017, p-value=0.045, p-value=0.033, p-value=0.003, respectively). DISCUSSION: Previously published evidence describing causal links between BPD development and comorbidities exists but data on their impact on BPD severity are scarce. In our study, severe BPD seemed to be associated with a higher frequency of comorbidities and complications. Further studies are needed to ascertain the impact of each morbidity on the severity of BPD and if measures to prevent them could lead to potentially milder BPD disease.
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Emetic tartar (ET), was used in the treatment of leishmaniasis but its use was discontinued due to its low therapeutic index. Liposomes have been shown to be a promising strategy for delivery of bioactive substances in the region of interest, in order to reduce and/or eliminate undesirable effects. In the present study, liposomes containing ET were prepared and characterized to evaluate acute toxicity as well as their leishmanicidal action using BALB/c mice with an inoculum of Leishmania (Leishmania) infantum. Liposomes were composed of egg phosphatidylcholine and 3ß-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol, with an average diameter of 200 nm, zeta potential of +18 mV, and ET encapsulated into liposomes at a concentration near 2 g/L. Healthy mice were treated with ET or liposome containing ET (Lip-ET) in a single dose of 16 mg/kg of Sb3+ intravenously and observed for 14 days. The death of two animals in the ET-treated group and no deaths in the Lip-ET-treated group was observed. Higher hepatic and cardiac toxicity were observed in animals treated with ET when compared to animals treated with Lip-ET, blank liposomes (Blank-Lip) and PBS. The study of antileishmanial efficacy was conducted by intraperitoneal administration of Lip-ET, for ten consecutive days. It was observed by limiting dilution that treatments with liposomal formulations containing ET, as well as Glucantime®, led to a significant reduction in parasitic load in spleen and liver (p < 0.05) when compared to the untreated control group.
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The aim of this study was to develop, characterize and evaluate the in vivo oral efficacy of self-emulsifying drug delivery systems (SEDDS) containing fexinidazole (FEX) in the experimental treatment of visceral leishmaniasis (VL). The developed FEX-SEDDS formulation presented as a clear, yellowish liquid, with absence of precipitate. The droplet size, polydispersion index and zeta potential after dilution in water (1:200) was of 91 ± 3 nm, 0.242 ± 0.005 and -16.7 ± 0.2, respectively. In the simulated gastric and intestinal media, the FEX-SEDDS had a size of 97 ± 1 and 106 ± 9 nm, respectively. The FEX retention in droplet after SEDDS dilution in simulated gastrointestinal media was almost 100 %. Antileishmanial efficacy studies showed that FEX-SEDDS was the only treatment able to significantly (p < 0.05) reduce the parasite burden in the liver and spleen of animals experimentally infected with Leishmania infantum. Our intestinal permeability data suggest that FEX-SEDDS showed no evidence of injury to the intestinal mucosa. These findings suggest that FEX-SEDDS can be a promising oral alternative for the treatment of VL caused by L. infantum.
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Antiprotozoários , Nitroimidazóis , Animais , Emulsões , Sistemas de Liberação de Medicamentos , Antiprotozoários/farmacologia , Administração Oral , Solubilidade , EmulsificantesRESUMO
Aim: Amphotericin B (AmB) is an antileishmanial drug with high toxicity; however, this drawback might overcome by decreasing the AmB self-aggregation state. This work aimed at evaluating the influence of cholesterol on the aggregation state of AmB loaded in a nanoemulsion (NE-AmB) for the treatment of cutaneous leishmaniasis. NE-AmB (1, 4 and 8 mg/kg/day) was administered intravenously to animals infected by Leishmania major every 2 days for a total of five injections. Results: Ultraviolet-visible spectroscopy and circular dichroism studies demonstrated that cholesterol reduced AmB aggregation state in NE. NE-AmB was stable after 180 days, and its hemolytic toxicity was lower than that observed for the conventional AmB. NE-AmB administered intravenously into animals infected by Leishmania major at 8 mg/kg was capable of stabilizing the lesion size and reducing the parasitic load. Conclusion: These findings support the NE potential as a stable nanocarrier for AmB in the treatment of cutaneous leishmaniasis.
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Antiprotozoários , Leishmania major , Leishmaniose Cutânea , Animais , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , ColesterolRESUMO
Liposomal amphotericin B (AmB) or AmBisome® is the most effective and safe therapeutic agent for visceral leishmaniasis (VL), but its clinical efficacy is limited in cutaneous leishmaniasis (CL) and HIV/VL co-infection. The aim of this work was to develop a formulation of AmB in PEGylated liposomes and compare its efficacy to AmBisome® in a murine model of CL. Formulations of AmB in conventional and PEGylated liposomes were characterized for particle size and morphology, drug encapsulation efficiency and aggregation state. Those were compared to AmBisome® in Leishmania amazonensis-infected BALB/c mice for their effects on the lesion size growth and parasite load. The conventional and PEGylated formulations showed vesicles with 100-130 nm diameter and low polydispersity, incorporating more than 95% of AmB under the non-aggregated form. Following parenteral administration in the murine model of CL, the PEGylated formulation of AmB significantly reduced the lesion size growth and parasite load, in comparison to control groups, in contrast to conventional liposomal AmB. The PEGylated formulation of AmB was also effective when given by oral route on a 2-day regimen. This work reports for the first time that PEGylated liposomal AmB can improve the treatment of experimental cutaneous leishmaniasis by both parenteral and oral routes.
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The liposomal amphotericin B (AmB) formulation, AmBisome®, still represents the best therapeutic option for cutaneous and visceral leishmaniasis. However, its clinical efficacy depends on the patient's immunological status, the clinical manifestation and the endemic region. Moreover, the need for parenteral administration, its side effects and high cost significantly limit its use in developing countries. This review reports the progress achieved thus far toward the understanding of the mechanism responsible for the reduced toxicity of liposomal AmB formulations and the factors that influence their efficacy against leishmaniasis. It also presents the recent advances in the development of more effective liposomal AmB formulations, including topical and oral liposome formulations. The critical role of the AmB aggregation state and release rate in the reduction of drug toxicity and in the drug efficacy by non-invasive routes is emphasized. This paper is expected to guide future research and development of innovative liposomal formulations of AmB.
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Cutaneous leishmaniasis (CL) is a neglected tropical skin disease caused by the protozoan genus Leishmania. The treatment is restricted to a handful number of drugs that exhibit toxic effects, limited efficacy, and drug resistance. Additionally, developing an effective topical treatment is still an enormous unmet medical challenge. Natural oils, e.g. the oleoresin from P. emarginatus fruits (SO), contain various bioactive molecules, especially terpenoid compounds such as diterpenes and sesquiterpenes. However, its use in topical formulations can be impaired due to the natural barrier of the skin for low water solubility compounds. Nanoemulsions (NE) are drug delivery systems able to increase penetration of lipophilic compounds throughout the skin, improving their topical effect. In this context, we propose the use of SO-containing NE (SO-NE) for CL treatment. The SO-NE was produced by a low energy method and presented suitable physicochemical characteristic: average diameter and polydispersity index lower than 180 nm and 0.2, respectively. Leishmania (Leishmania) amazonensis-infected BALB/c mice were given topical doses of SO or SO-NE. The topical use of a combination of SO-NE and intraperitoneal meglumine antimoniate reduced lesion size by 41 % and tissue regeneration was proven by histopathological analyses. In addition, a reduction in the parasitic load and decreased in the level of IFN-γ in the lesion may be associated, as well as a lower level of the cytokine IL-10 may be associated with a less intense inflammatory process. The present study suggests that SO-NE in combination meglumine antimoniate represents a promising alternative for the topical treatment of CL caused by L. (L.) amazonensis.
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Fabaceae , Leishmania mexicana/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Extratos Vegetais/farmacologia , Pele/efeitos dos fármacos , Tripanossomicidas/farmacologia , Administração Tópica , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Composição de Medicamentos , Quimioterapia Combinada , Emulsões , Fabaceae/química , Feminino , Interações Hospedeiro-Parasita , Leishmania mexicana/crescimento & desenvolvimento , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Antimoniato de Meglumina/farmacologia , Mesocricetus , Camundongos Endogâmicos BALB C , Nanopartículas , Carga Parasitária , Extratos Vegetais/isolamento & purificação , Pele/parasitologia , Pele/patologia , Tripanossomicidas/isolamento & purificaçãoRESUMO
Coronavirus disease, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is mainly transmitted through droplets, but other ways of transmission have been hypothesized. We report a case of vertical transmission of SARS-CoV-2 in a preterm born to an infected mother, confirmed by the presence of the virus in the neonatal blood, nasopharyngeal and oropharyngeal swabs collected in the first half an hour of life. The neonate presented with acute respiratory distress, similar to the findings in severely affected adults. This case highlights the importance of pregnancy, labor and neonatal period surveillance of affected mothers and their newborns.
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COVID-19/complicações , COVID-19/diagnóstico , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/etiologia , Síndrome Respiratória Aguda Grave/diagnóstico , Síndrome Respiratória Aguda Grave/etiologia , Adulto , Biomarcadores , COVID-19/epidemiologia , COVID-19/transmissão , Feminino , Humanos , Recém-Nascido , Reação em Cadeia da Polimerase , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Radiografia Torácica , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/transmissão , Tomografia Computadorizada por Raios XRESUMO
PURPOSE: Adapalene (AD) is one of the main retinoids used in the topical therapy of acne, an extremely common skin disease usually associated with psychological morbidity. However, like other retinoids, AD is frequently associated with skin irritation. To overcome the skin irritation, we proposed the encapsulation of AD in solid lipid nanoparticles (SLNs) using the ion pair strategy. METHODS: The developed SLN-AD was characterized by high-performance liquid chromatography, differential scanning calorimetry, X-ray diffraction, synchrotron small-angle X-ray scattering, and transmission electron microscopy. In vitro permeation tests using porcine skin and in vivo mice skin irritation test were performed to evaluate, respectively, the drug's skin distribution and the skin irritation. RESULTS: The characterization studies were able to demonstrate that the proposed strategy effectively provided high AD encapsulation in SLNs and its incorporation into a hydrophilic gel. Sustained release, epidermal targeting, and less skin irritation were observed for SLN-AD gel in comparison to the marketed AD gel. CONCLUSIONS: The studies demonstrated that the encapsulation of AD in SLNs through the formation of an ion pair is a valuable alternative to diminish the adverse skin reactions caused by AD and can optimize patient adherence to treatment.
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Acne Vulgar/tratamento farmacológico , Adapaleno/farmacologia , Preparações de Ação Retardada/química , Fármacos Dermatológicos/farmacologia , Ácidos Graxos/química , Nanocápsulas/química , Aminas/metabolismo , Animais , Transporte Biológico , Fármacos Dermatológicos/química , Composição de Medicamentos , Liberação Controlada de Fármacos , Epiderme/efeitos dos fármacos , Glicerol/química , Humanos , Íons/química , Transição de Fase , Pele , Absorção Cutânea , Suínos , Temperatura de TransiçãoRESUMO
Objectives: Cutaneous leishmaniasis is a neglected disease, associated with high morbidity, which is partially due to the toxicity of available therapies. The pentavalent antimonial derivatives intralesional infiltration has proven to be as effective as the intravenous drug-based therapy, however, there is a lack of robust safety data.Methods: Phase II, uncontrolled, unicenter clinical trial to assess the safety profile of a standardized meglumine antimionate intralesional therapy, based on weekly infiltrations.Results: Fifty-three patients were studied, predominantly men (60%) and young adults (43.7 ± 17.1 years). Overall, 86.9% of the patients had at least one clinical adverse event. Local events were the most frequent (83%), followed by systemic ones (47.3%). Fourteen participants (26%) presented biochemical abnormalities. In all cases, laboratorial alterations were classified as mild and treatment discontinuation was not required. Differently, the two hypersensitivity (3.8%) reactions observed led to permanent treatment interruption. QTc interval prolongation was recorded in 14 patients (25.5%). The following risk associations to adverse events were identified in the multiple analysis: hypertension with systemic clinical events and smoking with QT interval prolongation.Expert commentary: In general, MA-IL was well tolerated and although associated with local and systemic adverse events, there was a low risk of high intensity or severe complications.
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Antiprotozoários/administração & dosagem , Leishmaniose Cutânea/tratamento farmacológico , Antimoniato de Meglumina/administração & dosagem , Adulto , Antiprotozoários/efeitos adversos , Hipersensibilidade a Drogas/etiologia , Feminino , Humanos , Injeções Intralesionais , Masculino , Antimoniato de Meglumina/efeitos adversos , Pessoa de Meia-Idade , RiscoRESUMO
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 (200â¯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.
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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/parasitologiaRESUMO
OBJECTIVES: To evaluate the in vitro activity and in vivo efficacy of fexinidazole against the main species that cause visceral and cutaneous New World leishmaniasis. METHODS: The inhibitory concentrations of fexinidazole against Leishmania (Leishmania) infantum chagasi, Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis in amastigotes were determined by in vitro activity assays. For the in vivo evaluation, animals were infected with L. (L.) infantum chagasi, L. (L.) amazonensis, L. (V.) braziliensis or Leishmania (Viannia) guyanensis and divided into groups: (i) control; and (ii) treated with oral fexinidazole, from 50 to 300 mg/kg/day. For cutaneous leishmaniasis, the size of the lesion was determined weekly after the beginning of the treatment. Upon completion, parasites were recovered from the spleen and liver, or skin lesion and spleen, and evaluated by a limiting dilution assay. RESULTS: All Leishmania isolates were susceptible to fexinidazole in the in vitro assays. The viable parasites in the liver and spleen were reduced with 100 and 300 mg/kg/day, respectively, for L. (L.) infantum chagasi. For the species causing cutaneous leishmaniasis, the viable parasites in lesions and the size of the lesions were reduced, starting from 200 mg/kg/day. The viable parasites in the spleen were also reduced with 200 and 300 mg/kg/day for L. (V.) braziliensis and L. (L.) amazonensis. CONCLUSIONS: Considering the defined parameters, fexinidazole showed in vitro and in vivo activity against all tested species. This drug may represent an alternative treatment for the New World species.
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Antiprotozoários/administração & dosagem , Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Nitroimidazóis/administração & dosagem , Nitroimidazóis/farmacologia , Administração Oral , Animais , Modelos Animais de Doenças , Feminino , Masculino , Mesocricetus , Camundongos Endogâmicos BALB CRESUMO
OBJECTIVES: To evaluate the antimony (Sb) in plasma of patients who underwent a standardised meglumine antimoniate (MA) intralesional infiltration protocol for cutaneous leishmaniasis treatment. METHODS: The level of Sb in plasma was determined by atomic absorption spectroscopy, before and 1, 2, 4 and 6 hours after the first intralesional infiltration of MA to determine the parameters peak concentrations (C1 h ), area under curve of drug concentration in plasma from zero to 6 h (AUC0-6 h ) and elimination half-life (t½) of Sb. Blood samples were also collected weekly during the treatment period, always before infiltration. RESULTS: Fourteen patients underwent MA intralesional infiltration with doses ranging from 0.8 to 9 mg Sb/kg at the first infiltration. The C1 h ranged from 3850 to 47 095 mg × h/L and was the highest concentration obtained for 11 of 14 patients after the first intralesional infiltration of MA. A rapid initial phase of distribution lasting up to 4 h (2.6 ± 0.34 h) was followed by a slower elimination phase. Total skin lesion area, C1 h and AUC(0-6 h) were related to the dose of Sb infiltered (P < 0.05). Plasma Sb in samples collected weekly before the infiltration revealed antimony concentrations below the quantification limit (15.0 µg Sb/l) during the treatment period. CONCLUSIONS: Sb is quickly absorbed and eliminated after intralesional administration of MA, in a pattern similar to that reported with the Sb systemic administration. Using a therapeutic schedule limited to weekly intralesional infiltration of doses <10 mg Sb/kg does not result in plasma Sb accumulation.
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Antimônio/sangue , Antiprotozoários/administração & dosagem , Leishmaniose Cutânea/tratamento farmacológico , Antimoniato de Meglumina/administração & dosagem , Adulto , Feminino , Humanos , Injeções Intralesionais , Leishmaniose Cutânea/patologia , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
This work aimed to optimise a new nanoemulsion (NE) formulation loaded with Amphotericin B (AmB) and to evaluate its in vivo antileishmanial activity and in vitro haemolytic toxicity. The influence of gradual increases in pressure, using a high-pressure homogeniser, was evaluated. The NE was characterised for droplet size, polydispersity index, zeta potential and encapsulation efficiency (EE). For antileishmanial activity studies, AmB-NE was administered intravenously in mice infected by Leishmania infantum chagasi, which causes Visceral Leishmaniasis (VL). When the NE was submitted to gradual increases in pressure, the PI values and droplet size decreased. The droplet size (â¼145 nm) was lower than that obtained in previous studies. The zeta potential was negative and the EE was almost 100%. The haemolytic toxicity, evaluated on human red blood cells, for AmB-loaded NE was lower than that observed for the conventional AmB (C-AmB). C-AmB at 2 mg/kg was very toxic. In contrast, administration of the AmB-loaded NE, at same dose, did not result in any sign of acute toxicity, promoting a significant reduction in parasite burden as compared to the C-AmB. These findings suggest that this new AmB-loaded NE constitutes an attractive alternative for the treatment of VL due to improved efficacy and lower toxicity.
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Anfotericina B/administração & dosagem , Antiprotozoários/administração & dosagem , Leishmaniose Visceral/tratamento farmacológico , Nanopartículas , Anfotericina B/farmacologia , Anfotericina B/toxicidade , Animais , Antiprotozoários/farmacologia , Antiprotozoários/toxicidade , Emulsões , Feminino , Hemólise/efeitos dos fármacos , Humanos , Leishmania infantum/efeitos dos fármacos , Leishmaniose Visceral/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da PartículaRESUMO
Amphotericin B (AmB) is a drug of choice against life-threatening systemic fungal infections and an alternative therapy for the treatment of all forms of leishmaniasis. It is known that AmB and its conventional formulation cause renal damage; however, the lipid formulations can reduce these effects. The aim of the present study was to identify metabolic changes in mice treated with two different AmB formulations, a nanoemulsion (NE) (lipid system carrier) loaded with AmB and the conventional formulation (C-AmB). For this purpose, metabolic fingerprinting represents a valuable strategy to monitor, in a non-targeted manner, the changes that are at the base of the toxicity mechanism of AmB. Plasma samples of BALB-c mice were collected after treatment with 3 alternate doses of AmB at 1 mg kg-1 administered intravenously and analysed with CE, LC and GC coupled to MS. Blood urea nitrogen (BUN) and plasma creatinine levels were also analysed. Kidney tissue specimens were collected and evaluated. It was not observed that there were any alterations in BUN and creatinine levels as well as in histopathological analysis. Approximately 30 metabolites were identified as potentially related to early C-AmB-induced nephrotoxicity. Disturbances in the arachidonic acid, glycerophospholipid, acylcarnitine and polyunsaturated fatty acid (PUFA) pathways were observed in C-AmB-treated mice. In the AmB-loaded NE group, it was observed that there were fewer metabolic changes, including changes in the plasma levels of cortisol and pyranose. The candidate biomarkers revealed in this study could be useful in the detection of the onset and severity of kidney injury induced by AmB formulations.