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Desmonostoc salinum CCM-UFV059 (Desmonostoc) is a novel cyanobacterial strain of the order Nostocales isolated from a saline-alkaline lake. The acclimation towards salt and desiccation stress of Desmonostoc was compared to the related and well-characterized model strain Nostoc sp. PCC7120 (Nostoc). Salt-stressed cells of Desmonostoc maintained low cellular Na+ concentrations and accumulated high amounts of compatible solutes, mainly sucrose and to a lower extent trehalose. These features permitted Desmonostoc to grow and maintain photosynthesis at 2-fold higher salinities than Nostoc. Moreover, Desmonostoc also induced sucrose over-accumulation under desiccation, which allowed this strain to recover from this stress in contrast to Nostoc. Additional mechanisms such as the presence of highly unsaturated lipids in the membrane and an efficient ion transport system could also explain, at least partially, how Desmonostoc is able to acclimate to high salinities and to resist longer desiccation periods. Collectively, our results provide first insights into the physiological and metabolic adaptations explaining the remarkable high salt and desiccation tolerance, which qualify Desmonostoc as an attractive model for further analysis of stress acclimation among heterocystous N2 -fixing cyanobacteria.

Rivaroxaban is an anticoagulant (orally active direct Xa inhibitor) considered to reduce the risk of stroke and systemic embolism and treat deep vein thrombosis, pulmonary embolism, and other cardiovascular complications. Bioanalytical methods for rivaroxaban quantification in plasma are necessary for application in pharmacokinetic studies, as well as in drug therapeutic monitoring. In this work, we developed and validated a sensitive bioanalytical method using LC-MS/MS for rivaroxaban quantification in human plasma using an one-step liquid-liquid extraction. The linear concentration range was 1-600 ng/mL. The bioanalytical method was also applied to pharmacokinetic studies in healthy volunteers under fasting and fed conditions. The results demonstrated that the method is rapid, sensitive, and adequate for application in pharmacokinetic studies.

Blends of cellulose acetate (CA) and poly(3-hydroxybutyrate) (PHB) were prepared by the solvent-casting method in both the presence and the absence of a compatibilizer agent. The compatibilizer was synthesized by reactive processing between CA and PHB. From the differential scanning calorimetric analysis, it has been identified that CA/PHB blends are immiscible in the range of PHB content studied. The existence of interactions between the components was observed due to the displacement of glass transition temperature relative to PHB phase in the blend. The grafting copolymer promoted the increase of interactions between the phases specifically to compatibilized CA/40%wtPHB blend. This composition shows significant changes in crystalline percentage compared to the uncompatibilized blend. The existence of phase interactions modified the viscoelastic behavior of the compatibilized blends by introducing changes in the chain segment mobility due to the addition of compatibilizer as the dynamic mechanical analysis has pointed out. It was observed that different of the blends with lower PHB content, CA/40%wtPHB compatibilized blend with same compatibilizer content did not reach PHB saturation. This difference in behavior can be attributed to the fact that the content of compatibilizer agent used was the proper amount to promote both PHB domain size reduction and dispersion. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers

Summary Shifts from coral to algae dominance of corals reefs have been correlated to fish biomass loss and increased microbial metabolism. Here we investigated reef benthic and planktonic primary production, benthic dissolved organic carbon (DOC) release and bacterial growth efficiency in the Abrolhos Bank, South Atlantic. Benthic DOC release rates are higher while water column bacterial growth efficiency is lower at impacted reefs. A trophic model based on the benthic and planktonic primary production was able to predict the observed relative fish biomass in healthy reefs. In contrast, in impacted reefs, the observed omnivorous fish biomass is higher, while that of the herbivorous/coralivorous fish is lower than predicted by the primary production-based model. Incorporating recycling of benthic-derived carbon in the model through microbial and sponge loops explains the difference and predicts the relative fish biomass in both reef types. Increased benthic carbon release rates and bacterial carbon metabolism, but decreased bacterial growth efficiency could lead to carbon losses through respiration and account for the uncoupling of benthic and fish production in phase-shifting reefs. Carbon recycling by microbial and sponge loops seems to promote an increase of small-bodied fish productivity in phase-shifting coral reefs.

Benznidazole (BNZ) and nifurtimox are the only drugs available for treating Chagas disease. In this work, we validated a bioanalytical method for the quantification of BNZ in plasma aimed at improving sensitivity and time of analysis compared with the assays already published. Furthermore, we demonstrated the application of the method in a preclinical pharmacokinetic study after administration of a single oral dose of BNZ in Wistar rats. A Waters® Acquity UHPLC system equipped with a UV-vis detector was employed. The method was established using an Acquity® UHPLC HSS SB C18 protected by an Acquity® UHPLC HSS SB C18 VanGuard guard column and detection at 324 nm. The mobile phase consisted of ultrapure water-acetonitrile (65:35), and elution was isocratic. The mobile phase flow rate was 0.55 mL/min, the volume of injection was 1 μL, and the run time was just 2 min. The samples were kept at 25°C until injection and the column at 45°C for the chromatographic separation. The sample preparation was performed by a rapid protein precipitation with acetonitrile. The linear concentration range was 0.15-20 µg/mL. The pharmacokinetic parameters of BNZ in rats were determined and the method was considered sensitive, fast and suitable for application in pharmacokinetic studies.

The combination of isoniazid (INH), rifampicin (RMP) and pyrazinamide (PYR) is used in the treatment of tuberculosis. Although this treatment is effective in most clinical cases, the side-effects and the development of mycobacterium resistance have hindered its success. There is evidence that the combination of INH, RMP and ciprofloxacin (CIPRO) is useful in the treatment of tuberculosis. However, the influence of this drug combination on the hepatotoxicity of INH is unknown. In this study, the safety of combined INH, RMP and CIPRO was evaluated. Male albino rabbits (n = 20) were divided into four groups and subjected to multiple oral doses for 7 days according to the following treatments: water (group 1); 50 mg/kg INH (group 2); 50 mg/kg INH + 100 mg/kg RMP (group 3) and 50 mg/kg INH + 100 mg/kg RMP + 50 mg/kg CIPRO (group 4). Blood samples were taken before and after treatments for the determination of ALT, AST, ALP and bilirubin to assess hepatotoxicity. For pharmacokinetic analysis, serial blood samples were collected over 24 h on day 7 of treatment. Plasma concentrations of INH and acetylisoniazid (AcINH) were determined by HPLC. Biochemical parameters did not show any statistically significant differences between the groups that received the drug combinations. The pharmacokinetic profile of INH was also similar for both groups of combinations. These findings allow us to infer that the inclusion of CIPRO did not increase the risk of hepatotoxicity when compared with the classic combination of INH and RMP. Copyright © 2012 John Wiley & Sons, Ltd.

Primaquine is an important therapeutic resource for malaria treatment and it has wide activity against several pathogens. The haematotoxicity of primaquine is the major problem for its therapeutic application. This effect is aggravated by repeated use at high doses and by the wide fluctuation of plasma levels after administration. The primaquine prodrug (Phe-Ala-PQ) was planned in order to modify the pharmacokinetics and toxicity of primaquine. The in vitro conversion of Phe-Ala-PQ to primaquine, and the primaquine pharmacokinetics were evaluated in four groups of rats: two groups that received a single dose of Phe-Ala-PQ, one by intravenous and the other by gavage route, and two other groups that received primaquine diphosphate, by intravenous and gavage routes. In addition, the erythrocyte osmotic fragility was compared in two groups of rats that received multiple doses of primaquine diphosphate or Phe-Ala-PQ, as a parameter of haematotoxicity. The in vitro conversion of Phe-Ala-PQ to primaquine by plasma enzyme action was observed. The pharmacokinetic profile of primaquine from Phe-Ala-PQ was more favourable due to the lower fluctuation of plasma concentrations. Haematotoxicity was not evidenced in the prodrug administration. The results reinforce the need for further studies with this prodrug, promising an alternative in the therapeutic use of primaquine.

Made available in DSpace on 2019-09-12T16:56:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2012 Fundação de Amparo à Pesquisa do Estado de Minas Gerais (Fapemig) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Background: Recent studies have shown that being overweight or obese is associated with a higher risk of periodontitis. However, the literature offers an insufficient number of published reports regarding the effect of bariatric surgery on oral health. As such, the present study aims to determine the association between periodontal status and being over-weight/obese in prebariatric and postbariatric surgery populations of Brazil. Methods: Three hundred forty-five participants between 18 and 60 years of age, from both sexes, were grouped according to prebariatric or postbariatric surgery and underwent a complete periodontal examination. Biologic, demographic, and behavioral variables were analyzed in a Poisson regression model. Results: Considering the timing of bariatric surgery, the sample was divided into three groups: PRE-OP (preoperative, n = 133), POS-OP1 (postoperative 6 months, n = 140). Regardless of the type of surgery (PRE-OP, POS-OP1, POS-OP2), the prevalence of periodontitis proved to be high (81.45%). There was a statistically significant difference in the prevalence of periodontitis among the PRE-OP, POS-OP1, and POS-OP2 groups (P=0.040). In the Poisson regression model, after adjusting for biologic, demographic, and behavioral risk variables, only bleeding on probing remained significantly associated with the prevalence of periodontitis (P

Skeletal muscle atrophy is a debilitating response to starvation and many systemic diseases including diabetes, cancer, and renal failure. We had proposed that a common set of transcriptional adaptations underlie the loss of muscle mass in these different states. To test this hypothesis, we used cDNA microarrays to compare the changes in content of specific mRNAs in muscles atrophying from different causes. We compared muscles from fasted mice, from rats with cancer cachexia, streptozotocin-induced diabetes mellitus, uremia induced by subtotal nephrectomy, and from pair-fed control rats. Although the content of >90% of mRNAs did not change, including those for the myofibrillar apparatus, we found a common set of genes (termed atrogins) that were induced or suppressed in muscles in these four catabolic states. Among the strongly induced genes were many involved in protein degradation, including polyubiquitins, Ub fusion proteins, the Ub ligases atrogin-1/MAFbx and MuRF-1, multiple but not all subunits of the 20S proteasome and its 19S regulator, and cathepsin L. Many genes required for ATP production and late steps in glycolysis were down-regulated, as were many transcripts for extracellular matrix proteins. Some genes not previously implicated in muscle atrophy were dramatically up-regulated (lipin, metallothionein, AMP deaminase, RNA helicase-related protein, TG interacting factor) and several growth-related mRNAs were down-regulated (P311, JUN, IGF-1-BP5). Thus, different types of muscle atrophy share a common transcriptional program that is activated in many systemic diseases.

We report a rare case of a metastatic mucoepidermoid carcinoma (MEC) arising from the accessory parotid gland in a 14-year-old male. In the pre-surgical assessment, the MR and CT showed no other abnormalities apart from the primary lesion. The lesion was excised and confirmed as a high-grade MEC. Four months later, he presented with a recurrence in his right temple. A (18)F-FDG PET-CT showed distal metastases in cervical nodes and lungs. In view of the findings and poor prognosis of the patient, surgical intervention and radiotherapy were not given and palliative measures offered. This case shows the potential of molecular imaging with (18)F-FDG PET-CT in these patients.

A chloride-free Pd(OAc)2/Cu(OAc)2 system catalyzes the oxidation of organic substrates by molecular oxygen in nonacidic methanol solutions. Terminal olefins, i.e., 1-hexene, 1-octene, styrene, and 2-vinylnaphthalene, give the corresponding methyl ketones without a significant double-bond isomerization of long-chain substrates. The catalyst also promotes an unusual allylic oxidation of sterically encumbered trisubstituted internal double bonds in acyclic polyenes able to form η2−η2-chelates with palladium. Linalool and nerolidol, mono- and sesquiterpenic allylic alcohols, give corresponding allylic ethers arising from the exclusive oxidation of the internal double bonds. Monosubstituted terminal double bonds in both substrates remain intact due to the deactivating effect of the allylic hydroxyl group. Dihydromyrcene, a nonfunctionalized monoterpenic diene, gives allylic ether and methyl ketone arising from the oxidation of both trisubstituted and terminal double bonds, respectively. On the other hand, inte...