Design, Biological Evaluation, and Computer-Aided Analysis of Dihydrothiazepines as Selective Antichlamydial Agents.

Chlamydia trachomatis (CT) causes the most prevalent sexually transmitted bacterial disease in the United States. The lack of drug selectivity is one of the main challenges of the current antichlamydial pharmacotherapy. The metabolic needs of CT are controlled, among others, by cylindrical proteases and their chaperones (e.g., ClpX). It has been shown that dihydrothiazepines can disrupt CT-ClpXP. Based on this precedent, we synthesized a dihydrothiazepine library and characterized its antichlamydial activity using a modified semi-high-throughput screening assay. Then, we demonstrated their ability to inhibit ClpX ATPase activity in vitro, supporting ClpX as a target. Further, our lead compound displayed a promising selectivity profile against CT, acceptable cytotoxicity, no mutagenic potential, and good in vitro stability. A two-dimensional quantitative structure-activity relationship (2D QSAR) model was generated as a support tool in the identification of more potent antichlamydial molecules. This study suggests dihydrothiazepines are a promising starting point for the development of new and selective antichlamydial drugs.

Chemical composition and effects of ethanolic extract and gel of Cochlospermum regium (Schrank) Pilg. Leaves on inflammation, pain, and wounds.

ETHNOPHARMACOLOGICAL RELEVANCE: Cochlospermum regium is well-known as "Algodãozinho do cerrado" in folk Brazilian medicine, and is used to fight infections, inflammation and skin disorders. AIM OF THE STUDY: To identify the phytochemical constituents and the effects of the ethanolic extract of C. regium leaves (EECR) on inflammation and pain, and the effects of C. regium gel (GEECR) on wound healing. MATERIALS AND METHODS: Animals were treated with EECR (30-300 mg/kg) or GEECR (1.25 and 2.5%) and studies were conducted using carrageenan-induced pleurisy and paw edema tests, formalin-induced pain model, and excision wound model. RESULTS: In total, 25 compounds, including quercitrin, methyl gallate, and 1,2,3,4,6-pentagalloylhexose, with highest detectability were identified. The treatments reduced leukocyte migration, nitric oxide production, protein extravasation, edema, mechanical hyperalgesia, pain in both phases (neurogenic and inflammatory), cold hypersensitivity, and improved wound closure and tissue regeneration. CONCLUSIONS: The present findings established the anti-inflammatory, anti-nociceptive, and wound healing potential of the leaves of C. regium, confirming the potential therapeutic effect of this plant.

Candida species contamination in drinking groundwater from residence wells in three municipalities of midwestern Brazil and the potential human health risks.

Groundwater represents one of the largest safe drinking water sources worldwide; however, it has been threatened by increased human activities in recent years. Candida species express virulence factors that contribute to the establishment and worsening of infections, although little is known about the virulence profiles of these species in potable groundwater. The aim of this study was to detect the presence of yeasts in groundwater from residential wells and to evaluate the antifungal susceptibility profile, hydrolytic enzyme production, adhesion capacity, and biofilm formation of Candida spp. Fifty yeasts representing nine genera were isolated: Candida (48%), Meyerozyma (20%), Pichia (8%), Exophiala (8%), Clavispora (4%), Kodamaea (4%), Rhodotorula (4%), Hanseniaspora (2%), and Kazachstania (2%). Candida parapsilosis was the most commonly isolated species, and approximately 29% of the Candida isolates were resistant to at least one azole. All Candida isolates were able to produce hydrolytic enzymes and adhere to polystyrene, and most were classified as hydrophobic. Candida spp. can establish and form biofilms when cultivated in different media such as Sabouraud broth, water, and calcium hypochlorite. The use of contaminated groundwater for human consumption represents a possible route for the transmission of clinically relevant yeasts that can cause fungal infections, especially in immunocompromised individuals. Therefore, it is important to evaluate and establish effective measures for groundwater treatment to ensure the quality and safety for consumption.

General and genetic toxicology studies of Aleurites moluccana (L.) Willd. seeds in vitro and in vivo assays.

ETHNOPHARMACOLOGY RELEVANCE: Aleurites moluccana is popularly used for the diseases like ulcers, fever, headache, asthma, conjunctivitis, gonorrhea, inflammation, hepatitis, and rheumatism. The seed, also known as "noz da Índia", has been popularly consumed for weight loss purposes but reports of toxicity have been associated with its ingestion. In the literature, there are not enough studies to elucidate its toxicology, so evaluating the general and genetic toxicological of A. moluccana seeds can provide data to ensure their intake. AIM OF THE STUDY: The objective of the present study was to elucidate the oral toxicity, mutagenicity, genotoxicity and cytotoxicity of A. moluccana seeds in vitro and in vivo assays. MATERIALS AND METHODS: The chemical composition of the aqueous extract of A. moluccana seeds (AEAMS) was analyzed in relation to phenolic compounds, tannins, flavonoids and fatty acid. For the in vitro assays, the cytotoxic potential was assessed by the MTS assay whereas the mutagenic potential was assessed by the Ames test. For in vivo assays, was conducted an acute oral toxicity study, with "Up-and-Down Procedure" and repeated dose toxicity with "Repeated Dose 28-Day Oral Toxicity". To assess genetic damage, mutagenic potential was assessed by the micronucleus test whereas the polychromatic erythrocyte/normochromatic erythrocyte ratio was obtained with bone marrow cells to determine the cytotoxic potential and genotoxic potential was assessed by the comet assay using peripheral blood cells. RESULTS: AEAMS did not show cytotoxic and mutagenic potential in vitro. No clinical signs of toxicity were observed in animals after the acute oral toxicity test, suggesting that the LD50 of aqueous extract of A. moluccana seeds > 2000 mg/kg in a single dose by intragastric route. However, in toxicity at repeated doses for 28 days, the doses initially established (250; 500 and 750 mg/kg/day by intragastric route) caused mortality in the animals and the reestablished doses (25, 50 and 100 mg/kg/day by intragastric route) showed no changes in parameters or clinical signs attributed to toxicity. Furthermore, AEAMS also did not show mutagenic, genotoxic and cytotoxic potential in vivo. CONCLUSIONS: AEAMS did not show cytotoxic, genotoxic and mutagenic potential in vitro and in vivo. And although the AEAMS has an LD50 > 2000 mg/kg, and does not have physiological, biochemical, hematological, histopathological changes or clinical signs related to toxicity when administered in low concentrations and for a short period, in high concentrations and continued use caused toxicity and mortality in Wistar rats. In order to obtain complementary results, is recommended highly that further mid and long-term toxicological studies are investigated, and in no-rodent specie.

Genotypic variability and antifungal susceptibility of Candida tropicalis isolated from patients with candiduria / / Variabilidad genotípica y sensibilidad antifúngica de aislamientos de Candida tropicalis procedentes de pacientes con candiduria

Background. Candida tropicalis is an emerging major human pathogen in nosocomial infections, and it is considered the second or third species of Candida most isolated from urine cultures. Aims, The study aimed at characterizing genotypically C. tropicalis strains from patients with candiduria in a university hospital, and assessed the antifungal susceptibility profile. Methods. The study was conducted with hospitalized patients who developed urinary tract infection from C. tropicalis from June 2010 to June 2011 at the Grande Dourados University Hospital of the Federal University, Dourados, MS, Brazil. Susceptibility to the antifungal agents amphotericin B and fluconazole was determined by broth microdilution. The genotypic variability of isolates of C. tropicalis was analyzed by microsatellite markers and RAPD-PCR. Results. Only one isolate was resistant to amphotericin B (MIC → 16 μg/ml); the others were susceptible to fluconazole and amphotericin B. The genotypic variability by RAPD-PCR resulted in distinct profiles for RAPD markers. A total of 10 alleles were observed for the microsatellite loci, URA3 and CT14, which were grouped differently, and four associations were observed for locus URA3 and eight for locus CT14. Conclusions. C. tropicalis isolates from urine were susceptible to the antifungal agents tested. The genotyping techniques make possible proving the similarity and genetic diversity among isolates of C. tropicalis involved in nosocomial infections. This knowledge is important for the control and prevention of nosocomial infections caused by this yeast species (AU)

Antecedentes. Candida tropicalis es un patógeno humano emergente en las infecciones nosocomiales y es considerado la segunda o tercera especie de Candida más aislada en cultivos de orina. Objetivos. El objetivo del estudio fue caracterizar genotípicamente aislamientos de C. tropicalis procedentes de pacientes con candiduria de un hospital universitario, y evaluar su perfil de sensibilidad a los antifúngicos. Métodos. La investigación fue realizada con pacientes hospitalizados que desarrollaron una infección urinaria por C. tropicalis desde junio de 2010 hasta junio de 2011 en el Hospital Universitario de la Universidad Federal de Grande Dourados, Dourados, MS, Brasil. La sensibilidad a los agentes antifúngicos anfotericina B y fluconazol fue determinada mediante el método de microdilución en caldo. La variabilidad genotípica de los aislamientos de C. tropicalis se analizó mediante marcadores microsatélites y RAPD-PCR. Resultados. Sólo un aislamiento fue resistente a la anfotericina B (MIC → 16 mg/ml); los restantes aislamientos fueron sensibles al fluconazol y la anfotericina B. La variabilidad genotípica por RAPD-PCR dio como resultado perfiles distintos para los marcadores utilizados. Se observó un total de 10 alelos de los loci microsatélites, URA3 y CT14 fueron agrupados de manera diferente y se observaron cuatro asociaciones para el locus URA3 y ocho para el locus CT14. Conclusiones. Los aislamientos de C. tropicalis obtenidos de orina fueron sensibles a los antifúngicos probados. Las técnicas de genotipificación permiten demostrar la similitud y la diversidad genética de los aislamientos de C. tropicalis implicados en las infecciones nosocomiales. Este conocimiento es importante para el control y la prevención de las infecciones hospitalarias causadas por esta especie de levadura (AU)