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Almost 200 years ago, the first evidence described by Robert Bright (1836) showed the strong interaction between the kidneys and heart and, since then, the scientific community has dedicated itself to better understanding the mechanisms involved in the kidney–heart relationship, known in recent decades as cardiorenal syndrome (CRS). This syndrome includes a wide clinical variety that affects the kidneys and heart, in an acute or chronic manner. Moreover, it is well established in the literature that the immune system, the sympathetic nervous system, the renin–angiotensin–aldosterone, and the oxidative stress actively play a strong role in the cellular and molecular processes present in CRS. More recently, uremic molecules and epigenetic factors have been also shown to be key mediators in the development of syndrome. The present review intends to present the state of the art regarding CRS and to show the paths known, until now, in the long road between the kidneys and heart. [ABSTRACT FROM AUTHOR]

Ischaemia and reperfusion (I/R)-induced gastrointestinal disorders are caused by free radicals, resulting in organ damage and functional disarrangement. This study aimed to investigate the healing effects of hydroalcoholic extracts from the leaves of Eugenia punicifolia (Kunth) DC. (HEEP) in male and female Wistar rats with I/R-induced peptic injuries, and the role of antioxidants in improving this response. After I/R-induced gastric and duodenal injuries, male and female [intact (INT) and ovariectomized (OVZ)] rats were orally treated with HEEP for 6 days. Biochemical analysis was used to determine the catalase (CAT), superoxide dismutase (SOD), and myeloperoxidase (MPO) activities, as well as malondialdehyde and reduced glutathione levels, to measure the gastric and duodenal healing process. Six days of HEEP treatment significantly decreased the I/R-induced gastric [male (73.68%), INT (52.83%), and OVZ (43.13%)] and duodenal damage [male (57.03%), INT (56.04%), and OVZ (54.83%)] in all groups. In OVZ rats, the healing effect of HEEP occurred because of the increased activity of SOD (2x) and CAT (1.16x) in the gastric mucosa. In the duodenal mucosa of INT rats, the extract reduced MPO (20.83%) activity. The 6-day HEEP treatment improved the healing of I/R-induced peptic ulcer injury, with the system acting differently in males and females. The antioxidant system is an important component of the HEEP activity during post-I/R mucosal recovery. This result revealed the importance of antioxidant compounds in minimizing the severity of I/R-related events. [ABSTRACT FROM AUTHOR]

The corn-starch was able to reduce Pd(II) species under relatively low concentration (5.0 wt/vol) leading to the formation of a thermoresponsive palladium nanoparticles-containing hydrogel with D = 16.1 nm ± 6.4 nm. It was successfully applied to the Suzuki–Miyaura reaction step in neat water involved in the synthesis of (±)-N-acetyl-α-methyl-4-biphenylalanine ethyl ester, a direct precursor of an unnatural quaternary biarylalanine. [ABSTRACT FROM AUTHOR]

In this work, we isolated and selected oleaginous yeasts from rock field soils from two National Parks in Brazil (Caparaó and Serra dos Órgãos) with the potential to accumulate oil from xylose, the main pentose sugar found in lignocellulosic biomass. From the 126 isolates, two were selected based on their lipid contents. They were taxonomically identified as Papiliotrema laurentii (UFV-1 and UFV-2). Of the two, P. laurentii UFV-1 was selected as the best lipid producer. Under unoptimized conditions, lipid production by P. laurentii UFV-1 was higher in glucose than in xylose. To improve its lipid production from xylose, we applied response surface methodology (RSM) with a face-centered central composite design (CCF). We evaluated the effects of agitation rate, initial cell biomass (OD600), carbon/nitrogen ratio (C/N ratio) and pH on lipid production. P. laurentii UFV-1 recorded the highest lipid content, 63.5% (w/w) of the cell dry mass, under the following conditions: C/N ratio = 100:1, pH value = 7.0, initial OD600 = 0.8 and agitation = 300 rpm. Under these optimized conditions, biomass, lipid titer and volumetric lipid productivity were 9.31 g/L, 5.90 g/L and 0.082 g/L.h, respectively. Additionally, we determined the fatty acid composition of P. laurentii UFV-1 as follows: C14:0 (0.5%), C16:0 (28.4–29.4%), C16:1 (0.2%), C18:0 (9.5–11%), C18:1 (58.6–60.5%), and C20:0 (0.7–0.8%). Based on this composition, the predicted properties of biodiesel showed that P. laurentii UFV-1 oil is suitable for use as feedstock in biodiesel production. [ABSTRACT FROM AUTHOR]

Legislation governing strict-protection nature reserves in Brazil in principle precludes human habitation, but virtually all Amazon reserves are nonetheless inhabited. Historical ecology research reported herein assesses the impacts of occupation and resource use by beiradeiros (forest peasants) on the forests of a strictly designated nature reserve in the Iriri River basin (Brazilian Amazon). The hypothesis is that traditional beiradeiros activities are congruent with the aims of conservation of the reserve because their impacts are either neutral or enhance diversity of forest landscapes and biota. We designed the methodology underlying data collection to integrate forest inventory with archaeological techniques in two contrasting forest types (terra firme and seasonally inundated forest), faunal surveys, freelisting of tree terms by beiradeiros, and participant observation, in order to determine biological diversity indices, forest age and the parameters of traditional knowledge that encode such diversity in local vocabulary. Our research results lead us to reject the premise that traditional peasant activities lead to ecological degradation or impoverishment, and suggest that the rationale underpinning strictly protected nature reserves should be re-examined. [ABSTRACT FROM AUTHOR]

Night biomass loss due to respiratory activity can significantly impact the phytoplankton biomass productivity and the yield of specific biomolecules. A decrease in biomass loss can be achieved by cyclic two-stage cultivation (CTSC) employing an organic carbon source during the dark phase of the photoperiod. Thus, sugarcane vinasse was used as carbon supply in CTSC to influence the Arthrospira maxima growth. The impact of carbon supply on CTSC was assessed and the results show that splitting the supplementation volume of 60 mL supplemented vinasse into three doses of 20 mL during the dark phase increased biomass productivity by 35.4%, although the maximum exponential growth rate was unaffected. The cyanobacterium also takes up CO2 (supplied in the light phase) as HCO3−, high concentrations of which increase biomass loss. Thus, carbon assimilation in CTSC is higher when the concentration of dissolved inorganic carbon is reduced. Optimization of organic and inorganic carbon supply in CTSC with the response surface methodology resulted in an increased growth rate (from 0.73 to 1.18-1.62 day−1) and a reduction of cultivation time (from 7 to 5 days), thus producing a synergistic effect of reduced night biomass loss and vinasse treatment. After cultivating A. maxima for 5 days under optimal conditions (culture medium with 6.81 g L−1 of NaHCO3 and adding 1.5% (v/v) vinasse every 4 h during the dark phase), the reduction of chemical oxygen demand and electrical conductivity demonstrates that removal of organic matter present in the vinasse was due to cell growth during CTSC. [ABSTRACT FROM AUTHOR]

Background and Objectives: β-Lapachone is a drug candidate in phase II clinical trials for treatment of solid tumors. The therapeutic efficacy of β-lapachone is closely related to its metabolism, since this o-naphthoquinone produces cytotoxic effect after intracellular bioreduction by reactive oxygen species formation. The aim of this study was to produce β-lapachone human blood phase I metabolites to evaluate their cytotoxic activities. Methods: The biotransformation of β-lapachone was performed using Mucor rouxii NRRL 1894 and Papulaspora immersa SS13. The metabolites were isolated and their chemical structures determined from spectrometric and spectroscopic data. Cell cytotoxicity assays were carried out with β-lapachone and its metabolites using the neoplastic cell line SKBR-3 derived from human breast cancer and normal human fibroblast cell line GM07492-A. Results: Microbial transformation of β-lapachone by filamentous fungi resulted in the production of five metabolites identical to those found during human blood metabolism, a novel metabolite and a product stated before only in a synthetic procedure. The analysis of the results showed that β-lapachone metabolites were not cytotoxic for the neoplastic cell line SKBR-3 derived from human breast cancer and the normal human fibroblast cell line GM07492-A. The cytotoxic activity assay against the neoplastic cell line SKBR-3 revealed that the lowest half-maximal inhibitory concentration (IC) values of these β-lapachone metabolites were 33- to 52-fold greater than IC values of β-lapachone. Conclusions: The cytotoxic activity of β-lapachone in vivo may be reduced due to its swift conversion in blood. [ABSTRACT FROM AUTHOR]

Background and Objectives: Atovaquone is a hydroxynaphthoquinone with selective action in the mitochondrial respiratory chain of malaria parasite. It is employed for both the treatment and prevention of malaria, in a combination with proguanil. The aim of this study was to elucidate the in vitro metabolites from atovaquone and to evaluate their cytotoxic activities. Methods: The biotransformation of atovaquone was performed using Mucor rouxii NRRL 1894, Cunninghamella echinulata var. elegans ATCC 8688a and C. elegans ATCC 10028b, which have been reported as microbial models of mammalian drug metabolism. Experiments were also carried out with two probiotic strains from the human intestinal tract: Bifidobacterium sp. and Lactobacillus acidophilus. The phase I metabolite was isolated, its chemical structure was elucidated and its toxicity was evaluated using the neoplastic cell line SKBR-3 derived from human breast cancer and normal human fibroblast cell line GM07492-A. Cell cytotoxicity assays were also carried out with atovaquone. Result: Only the fungi were able to convert atovaquone to metabolite trans-3-[4′-(4″-chlorophenyl)cyclohexyl)-1,2-dioxo-dihydro-1H-indene-3-carboxylic acid. The metabolite displayed 50 % inhibitory concentration (IC) values of 110.20 ± 2.2 and 108.80 ± 1.5 µmol/L against breast cancer cell line SKBR-3 and fibroblasts cell line GM07492-A, respectively. The IC values of atovaquone were 282.30 ± 1.8 and 340.50 ± 1.4 µmol/L against breast cancer and normal fibroblasts cell lines, respectively. Conclusions: The produced metabolite was more toxic than atovaquone and was not selective to normal or cancer cell lines. The present study is the first to report the production of atovaquone metabolite. [ABSTRACT FROM AUTHOR]

A substantial extinction of megafauna occurred in Australia between 50 and 45 kyr ago, a period that coincides with human colonization of Australia. Large shifts in vegetation also occurred around this time, but it is unclear whether the vegetation changes were driven by the human use of fire-and thus contributed to the extinction event-or were a consequence of the loss of megafaunal grazers. Here we reconstruct past vegetation changes in southeastern Australia using the stable carbon isotopic composition of higher plant wax n-alkanes and levels of biomass burning from the accumulation rates of the biomarker levoglucosan from a well-dated sediment core offshore from the Murray-Darling Basin. We find that from 58 to 44 kyr ago, the abundance of plants with the C4 carbon fixation pathway was generally high-between 60 and 70%. By 43 kyr ago, the abundance of C4 plants dropped to 30% and biomass burning increased. This transient shift lasted for about 3,000 years and came after the period of human arrival and directly followed megafauna extinction at 48.9-43.6 kyr ago. We conclude that the vegetation shift was not the cause of the megafaunal extinction in this region. Instead, our data are consistent with the hypothesis that vegetation change was the consequence of the extinction of large browsers and led to the build-up of fire-prone vegetation in the Australian landscape. [ABSTRACT FROM AUTHOR]

Complexes [Ga(2Ac4 pFPh)]NO ( 1), [Ga(2Ac4 pClPh)]NO ( 2), [Ga(2Ac4 pIPh)]NO ( 3), [Ga(2Ac4 pNOPh)]NO·3HO ( 4) and [Ga(2Ac4 pT)]NO ( 5) were obtained with 2-acetylpyridine N(4)- para-fluorophenyl-(H2Ac4 pFPh), 2-acetylpyridine N(4)- para-chlorophenyl-(H2Ac4 pClPh), 2-acetylpyridine N(4)- para-iodophenyl-(H2Ac4 pIPh), 2-acetylpyridine N(4)- para-nitrophenyl-(H2Ac4 pNOPh) and 2-acetylpyridine N(4)- para-tolyl-(H2Ac4 pT) thiosemicarbazone. 1-5 presented antimicrobial and cytotoxic properties. Coordination to gallium(III) proved to be an effective strategy for activity improvement against Pseudomonas aeruginosa and Candida albicans. The complexes were highly cytotoxic against malignant glioblastoma and breast cancer cells at nanomolar concentrations. The compounds induced morphological changes characteristic of apoptotic death in tumor cells and showed no toxicity against erythrocytes. 2 partially inhibited tubulin assembly at high concentrations and induced cellular microtubule disorganization, but this does not appear to be the main mechanism of cytotoxic activity. [ABSTRACT FROM AUTHOR]

The proposal of this work was to investigate the effect of the radioactive (NH)PtCl, cis-diamminedichloroplatinum (II) or CDDP* on malignant glioma cells and verify if the low-dose continuous internal radio-chemotherapy would be able to produce additive effects. The antitumoral activity of CDDP* and the non labeled cisplatin, CDDP, were evaluated in glioblastoma. Cisplatin was cytotoxic for glioblastoma cells in a dose dependent manner. Treatment with CDDP*, (IC = 1.75 ± 0.07 μM), proved to be more potent than using just CDDP, (IC = 4.96 ± 0.40 μM). These results suggest that cisplatin is a very potent radiosensitizer evoking a supra additive effect. Internal radio-chemotherapy treatment based on CDDP* may be useful alternative to reduce the drug concentration required for effective inhibition of glioblastoma growth. [ABSTRACT FROM AUTHOR]

Lyophilized cells of the non-pathogenic yeast Saccharomyces boulardii are used in many countries for the treatment of several types of diarrhoea and other gastrointestinal diseases. Although the cells must be viable, their mechanism of action is unknown. The disaccharide trehalose is a protectant against several forms of environmental stress in yeast and is involved in maintaining cell viability. There is no information on the enzymes involved in degradation of trehalose in S. boulardii. The aim of the present study was to characterize trehalase activity in this yeast. Cells of S. boulardii grown in glucose exhibited neutral trehalase activity only in the exponential phase. Acidic trehalase was not detected in glucose medium. Cells grown in trehalose exhibited acid and neutral trehalase activities at all growth stages, particularly in the exponential phase. The optimum pH and temperature values for neutral trehalase activity were determined as 6.5 and 30 °C respectively, the half-life being approximately 3 min at 45 °C. The relative molecular mass of neutral trehalase is 80 kDa and the Km 6.4 mM (±0.6). Neutral trehalase activity at pH 6.5 was weakly inhibited by 5 mM EDTA and strongly inhibited by ATP, as well as the divalent ions Cu++, Fe++ and Zn++. Enzyme activity was stimulated by Mg++ and Ca++ only in the absence of cAMP. The presence of cAMP with no ion additions increased activity by 40%. [ABSTRACT FROM AUTHOR]