Effects of bioconversion by Battus polydamas on the chemical composition of Aristolochia spp. and evaluation of antimicrobial activity and biocompatibility

Aristolochia plants are emblematic from an ethnopharmacological viewpoint and are know to possess numerous biological properties, including antiseptic. However, the medicinal potential of these species is debatable because of their representative chemical constituents, aristolochic acids (AAs) and aristolactams (ALs), which are associated, for instance, with nephropathy and cancer. These contrasting issues have stimulated the development of approaches intended to detoxification of aristoloquiaceous biomasses, among which is included the bioconversion method using larvae of the specialist phytophagous insect Battus polydamas, previously shown to be viable for chemical diversification and to reduce toxicity. Thus, eleven Aristolochia spp. were bioconverted, and the antimicrobial activities of the plant methanolic extracts and its respective bioconversion products were evaluated. The best results were found for Aristolochia esperanzae, Aristolochia gibertii, and Aristolochia ringens against Bacillus cereus, with MIC ranging from 7.8 to 31.25 μg/mL. These three species were selected for chemical, antioxidant, cytotoxic, hemolytic, and mutagenic analyses. Chemical analysis revealed 65 compounds, 21 of them possible bioconversion products. The extracts showed potential to inhibit the formation and degradation of B. cereus biofilms. Extracts of A. gibertii and its bioconverted biomass showed antioxidant activity comparable to dibutylhydroxytoluene (BHT) standard. Bioconversion decreased the hemolytic activity of A. esperanzae and the cytotoxicities of A. esperanzae and A. gibertii. None of the extracts was found to be mutagenic. The bioactivities of the fecal extracts were maintained, and biocompatibility was improved. Therefore, the results obtained in this study reveal positive expectations about the natural detoxification process of the Aristolochia species.

Design and Synthesis of Novel 3-Nitro-1H-1,2,4-triazole-1,2,3-triazole-1,4-disubstituted Analogs as Promising Antitrypanosomatid Agents: Evaluation of In Vitro Activity against Chagas Disease and Leishmaniasis

A series of 28 compounds, 3-nitro-1H-1,2,4-triazole, were synthesized by click-chemistry with diverse substitution patterns using medicinal chemistry approaches, such as bioisosterism, Craig-plot, and the Topliss set with excellent yields. Overall, the analogs demonstrated relevant in vitro antitrypanosomatid activity. Analog 15g (R1 = 4-OCF3-Ph, IC50 = 0.09 μM, SI = >555.5) exhibited an outstanding antichagasic activity (Trypanosoma cruzi, Tulahuen LacZ strain) 68-fold more active than benznidazole (BZN, IC50 = 6.15 μM, SI = >8.13) with relevant selectivity index, and suitable LipE = 5.31. 15g was considered an appropriate substrate for the type I nitro reductases (TcNTR I), contributing to a likely potential mechanism of action for antichagasic activity. Finally, 15g showed nonmutagenic potential against Salmonella typhimurium strains (TA98, TA100, and TA102). Therefore, 3-nitro-1H-1,2,4-triazole 15g is a promising antitrypanosomatid candidate for in vivo studies.

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.

Synthesis, structural characterization, and prospects for new cobalt (II) complexes with thiocarbamoyl-pyrazoline ligands as promising antifungal agents

Candida spp. cause invasive fungal infections. One species, Candida glabrata, may present intrinsic resistance to conventional antifungal agents, thereby increasing mortality rates in hospitalized patients. In this context, metal complexes present an alternative for the development of new antifungal drugs owing to their biological and pharmacological activities demonstrated in studies in the last decades. Accordingly, in this study we have synthesized and characterized two new Co(II) complexes with thiocarbamoyl-pyrazoline ligands to assess their antimicrobial, mutagenic, and cytotoxic potential. For antimicrobial activity, the broth microdilution method was performed against ATCC strains of Candida spp. and fluconazole dose-dependent isolates of C. glabrata obtained from urine samples. The Ames test was used to assess mutagenic potential. The reduction method of the MTS reagent (3 [4,5-dimethylthiazol-2-yl]-5-[3-carboxymethoxyphenyl]-2-[4-sulfophenyl]-2H-tetrazolium) was performed with HeLa, SiHa, and Vero cells to determine cytotoxicity. Both complexes exhibited fungistatic and fungicidal activity for the yeasts used in the study, demonstrating greater potential for C. glabrata ATCC 2001 and the C. glabrata CG66 isolate with a Minimum Inhibitory Concentration MIC from 3.90 to 7.81 μg mL^-1 and fungicidal action from 7.81 to 15.62 μg mL^-1. The complexes inhibited and degraded biofilms by up to 90% and did not present mutagenic and cytotoxic potential at the concentrations evaluated for MIC. Thus, the complexes examined herein suggest promising alternatives for the development of new antifungal drugs.

Prokaryotic communities of acidic peatlands from the southern Brazilian Atlantic Forest

The acidic peatlands of southern Brazil are ecosystems essential for the maintenance of the Atlantic Forest, one of the 25 hot-spots of biodiversity in the world. In this work, we investigated the composition of prokaryotic communities in four histosols of three acidic peatland regions by constructing small-subunit (SSU) rRNA gene libraries and sequencing. SSU rRNA gene sequence analysis showed the prevalence of Acidobacteria (38.8%) and Proteobacteria (27.4%) of the Bacteria domain and Miscellaneous (58%) and Terrestrial (24%) groups of Crenarchaeota of the Archaea domain. As observed in other ecosystems, archaeal communities showed lower richness than bacterial communities. We also found a limited number of Euryarchaeota and of known methanotrophic bacteria in the clone libraries.

Effects of the pollution by petroleum on the tracheids along the stem of Podocarpus lambertii Klotzsch ex Endl., Podocarpaceae

Podocarpus lambertii Klotzsch ex Endl. (Podocarpaceae) is native and a member of the Pinophyta (Gymnosperm) of southern Brazil, locally known as "pinheiro-bravo". The present work aims to investigate the effects of petroleum on the tracheids dimensions. Wood samples from twenty individuals were studied along the stem, ten being exposed to pollution and ten used as a control set. The wood samples were collected from incisions at three levels: at the ground level, and one and two metres above the ground level. From these samples, sub-samples were selected at the border of the growth layers in the vascular cambium-medulla direction. The methodology followed that traditionally recommended for plant anatomy studies, with analyses done by light microscopy (OLYMPUS - BX41) assisted by the software Image Pro-plus for measurements. Comparison of the individuals exposed to petroleum with the control set, showed that the length, diameter and cell wall width of the tracheids of the former were smaller, a trend which was statistically significant according to the Student's t-test. These traits were observed mainly on the tracheids of the last growth layer, corresponding to the year in which the individuals were exposed to petroleum.

[Post-traumatic stress: the mechanisms of trauma]

Since the first description of stress syndrome, by Hans Selye in 1936, much has been investigated concerning the etiological mechanisms of stress. In recent years the intense research in the field of the neurobiology of stress, namely in Post-Traumatic Stress Disorder (PTSD), revealed some of the mechanisms and neurological structures involved with stress. A systematic research of literature published until December of 2006 was made, through the MEDLINE using as keywords neurobiology, stress, post traumatic stress disorder, neuroendocrine, neurochemical, neuroimmunological, neuroimaging. Of a total of 70 found articles, 39 were selected by its adequacy and acquired for the accomplishment of this revision. Also, reference books were consulted for the areas of theoretical concepts of stress and phenomenology of trauma. The authors intend to review the way cerebral structures, multiple neuronal and hormonal ways form a complex mechanism of reaction to stress. It is intended with this article to demonstrate the relation between psychopathological events, namely in PTSD, the phenomenology of the trauma and neurobiological changes.

Demographic of short gut syndrome: increasing demand is not followed by referral of potential candidates for small bowel transplantation

BACKGROUND

Despite improvements in small bowel transplantation (SBTx), early referral of patients with irreversible intestinal failure (IF) remains a major obstacle. In this study we evaluated the demand for SBTx among seven surgical pediatric centers located at least 200 km from our center.

METHODS

From 1997 to 2001, 640 patients have been treated for neonatal diseases, including 248 who underwent a minor or major intestinal resection. Twenty-four patients with major resections presented with short gut syndrome, requiring total parenteral nutrition (TPN). The greatest demand was in postsurgical neonates with necrotizing enterocolitis, gastroschiesis, onphalocoeles, or midgut volvulus, and in three adults with postradiotherapy arteritis (n = 2) and mesenteric vein thromboses (n = 1). The median length of residual bowel after resection was 20 to 30 cm, without an ileocecal valve. Four patients were referred for SBTx evaluation; three died while awaiting a donor; 20 were not referred, among whom 14 died of TPN complications.

RESULTS

Approximately 62 children per year require nutritional support for IF, most of whom develop complications related to TPN. Because many patients who are TPN-dependent develop complications, we believe that early referral would reduce mortality.

CONCLUSIONS

Greater medical awareness about the feasibility of SBTx procedures and earlier referral may improve results and quality of life after transplant.

Teleconsultation for cooperative acquisition, analysis and reporting of ultrasound studies

We have developed a teleconsultation system to support cooperation between doctors at different institutions in the acquisition, analysis and reporting of ultrasound studies. All the relevant activities were supported by the application. The system enabled remote supervision of the ultrasound study as it was being performed, cooperative static image acquisition and analysis, as well as report writing. Cooperative analysis of previously acquired studies was also possible. The system is undergoing evaluation in five hospitals in Portugal.