Similar hypotensive responses to resistance exercise with and without blood flow restriction

Low intensity resistance exercise (RE) with blood flow restriction (BFR) has gained attention in the literature due to the beneficial effects on functional and morphological variables, similar to those observed during traditional RE without BFR, while the effects of BFR on post-exercise hypotension remain unclear. The aim of the present study was to compare the blood pressure (BP) response of trained normotensive individuals to RE with and without BFR. In this cross-over randomized trial, eight male subjects (23.8 ± 4 years, 74 ± 3 kg, 174 ± 4 cm) completed two exercise protocols: traditional RE (3 x 10 repetitions at 70% one-repetition maximum [1-RM]) and low intensity RE (3 x 15 repetitions at 20% 1-RM) with BFR. Blood pressure measurements were performed after 15 min of seated rest (0), immediately after and 10 min, 20 min, 30 min, 40 min, 50 min and 60 min after the experimental sessions. Similar hypotensive effects for systolic BP (SBP) were observed for both protocols (P < 0.05) after exercise, with no differences between groups (P > 0.05) and no statistically significant difference for diastolic BP (P > 0.05). These results suggest that in normotensive trained individuals, both traditional RE and RE with BFR induce hypotension for SBP, which is important to prevent cardiovascular disturbances.     

Molecular and cellular events at the site of myocardial infarction: from the perspective of rebuilding myocardial tissue

The potential for bone marrow-derived progenitor cells (BMDPC) to regenerate myocardial tissue following infarction depends on homing, migration, nourishment, and spatially appropriate growth of BMDPC. Requisite to these objectives is the expression of adhesion molecules (ICAM-1) and chemoattractant cytokines (MCP-1), matrix metalloproteinase (MMP) activity, a neovasculature, and fibrillar collagen scaffolding. We found that enhanced ICAM-l and MCP-1, as well as MMP activity on day 3 and 7 postMI, are present to facilitate the homing, chemotaxis, and migration of circulating cells into the infarct site. The vascular network formed at the infarct site contains a ratio of conduit to exchange vessels that is greater than that for control tissue and therefore its ability to nourish BMDPC for their growth appears to be tenuous. These findings, together with the dense formation of a fibrillar collagen scar beyond week 2, suggest the optimal time to rebuild myocardium from BMDPC resides within 2 week postMI.     

Valorization of an industrial organosolv–sugarcane bagasse lignin: Characterization and use as a matrix in biobased composites reinforced with sisal fibers

In the present study, the main focus was the characterization and application of the by‐product lignin isolated through an industrial organosolv acid hydrolysis process from sugarcane bagasse, aiming at the production of bioethanol. The sugarcane lignin was characterized and used to prepare phenolic‐type resins. The analysis confirmed that the industrial sugarcane lignin is of HGS type, with a high proportion of the less substituted aromatic ring p‐hydroxyphenyl units, which favors further reaction with formaldehyde. The lignin–formaldehyde resins were used to produce biobased composites reinforced with different proportions of randomly distributed sisal fibers. The presence of lignin moieties in both the fiber and matrix increases their mutual affinity, as confirmed by SEM images, which showed good adhesion at the biocomposite fiber/matrix interface. This in turn allowed good load transference from the matrix to the fiber, leading to biobased composites with good impact strength (near 500 J m^?1 for a 40 wt% sisal fiber‐reinforced composite). The study demonstrates that sugarcane bagasse lignin obtained from a bioethanol plant can be used without excessive purification in the preparation of lignocellulosic fiber‐reinforced biobased composites displaying high mechanical properties. Biotechnol. Bioeng. 2010;107:612–621. © 2010 Wiley Periodicals, Inc.     

Asymmetry of Leg Use During Prey Handling in the Spider Scytodes globula (Scytodidae)

In spitting spiders Scytodes globula collected in the field, anterior leg loss was more frequent on the left than on the right side, possibly as an outcome of predatory episodes. A laboratory study was performed in which intact adult females of S. globula were placed with individuals from three species of recluse spiders, Loxosceles intermedia, L. gaucho, and L. laeta. The frequency of probing touches by spitting spiders to their prey was significantly higher with left leg I than with right leg I. Left leg II and right leg II also differed in touching frequency, but in a less marked way. The results, which may represent the first evidence of behavioral laterality in a spider species, suggest that behavioral asymmetry may be an ancient evolutionary trait.     

Plasma kinetics of a cholesterol-rich emulsion in subjects with or without coronary artery disease

A cholesterol-rich emulsion (LDE) that resembles the LDL lipidic structure is taken-up by LDL receptors after intravenous injection by means of apolipoprotein E it acquires in the circulation and can be used to probe LDL metabolism. In this study, LDE was labeled with [14C]cholesteryl oleate and [3H]cholesterol and injected into 19 patients with coronary artery disease (CAD) and into 14 subjects without CAD to verify whether the kinetic behavior of the radioactive lipids is different in CAD. Blood was sampled over 24 h for radioactivity measurement after lipid extraction and separation by thin-layer chromatography. Fractional clearance rate (FCR, in h-1) of [14C]cholesteryl ester was not different in CAD and nonCAD expressed as median (25%; 75%): 0.08 (0.062; 0.134) h-1 versus 0.06 (0.04; 0.083) h-1, P = 0.167. However, [3H]cholesterol FCR was greater in CAD than in nonCAD (mean +/- SEM): 0.163 +/- 0.016 h-1 versus 0.077 +/- 0.014 h-1, P < 0.001. Esterification of the LDE [3H]cholesterol was also greater in CAD subjects than nonCAD at 10 h and 24 h after emulsion injection (P = 0.029 and 0.024 respectively). In conclusion, both removal from the plasma and esterification of the LDE-cholesterol were increased in CAD. These findings may contribute for unraveling pro-atherogenic mechanisms and the establishment of novel CAD markers.     

Antimicrobial resistance and plasmid profiles of Campylobacter jejuni and Campylobacter coli from human and animal sources

AIMS: The purpose of this study was to determine the susceptibility of Campylobacter jejuni and Campylobacter coli isolates to antimicrobial agents and to investigate the presence of plasmid DNA. METHODS AND RESULTS: A total of 15 clinical isolates from children faeces, and 29 animal isolates of Campylobacter jejuni (n=22) and Campylobacter coli (n=22) were tested for susceptibility to 9 antimicrobial agents using a disc diffusion method, and screened for the presence of plasmid DNA by agarose gel electrophoresis. Of the 44 isolates, 56.8% were resistant to sulphonamide, 25% to norfloxacin, 18.2% to erythromicin, ciprofloxacin and ampicillin, and 13.6% to tetracycline. All isolates were susceptible to gentamicin, chloramphenicol and cefotaxime. Plasmids were detected in one Camp. jejuni (4.54%) strain isolated from sheep and in six (27.27%) Camp. coli strains isolated from rhesus monkey(3), swine(2), and poultry(1) with sizes ranging from 3.4 to 50 kb. CONCLUSIONS: The majority of the human isolates were susceptible to antibiotics commonly used for the treatment of campylobacteriosis. SIGNIFICANCE AND IMPACT OF THE STUDY: The origin and spread of Campylobacter resistance to antibiotics are discussed, with particular respect to the current situation in Brazil.     

An overview of heat stress in tomato (Solanum lycopersicum L.)

Heat stress has been defined as the rise of temperature for a period of time higher than a threshold level, thereby permanently affecting the plant growth and development. Day or night temperature is considered as the major limiting factor for plant growth. Earlier studies reported that night temperature is an important factor in the heat reaction of the plants. Tomato cultivars capable of setting viable fruits under night temperatures above 21 °C are considered as heat-tolerant cultivars. The development of breeding objectives is generally summarized in four points: (a) cultivars with higher yield, (b) disease resistant varieties in the 1970s, (c) long shelf-life in 1980s, and (d) nutritive and taste quality during 1990s. Some unique varieties like the dwarf “Micro-Tom”, and the first transgenic tomato (FlavrSavr) were developed through breeding; they were distributed late in the 1980s.High temperature significantly affects seed, pollen viability and root expansion. Researchers have employed different parameters to evaluate the tolerance to heat stress, including membrane thermo stability, floral characteristics (Stigma exertion and antheridia cone splitting), flower number, and fruit yield per plant. Reports on pollen viability and fruit set/plant under heat stress by comparing the pollen growth and tube development in heat-treated and non-heat-stressed conditions are available in literature. The electrical conductivity (EC) have been used to evaluate the tolerance of some tomato cultivars in vitro under heat stress conditions as an indication of cell damage due to electrolyte leakage; they classified the cultivars into three groups: (a) heat tolerant, (b) moderately heat tolerant, and (c) heat sensitive.It is important to determine the range in genetic diversity for heat tolerance in tomatoes. Heat stress experiments under field conditions offer breeders information to identify the potentially heat tolerant germplasm.     

Dynamics of artisanal fisheries in two Brazilian Amazonian reserves: implications to co-management

In this study we compare the dynamics of artisanal fishery in two adjacent reserves located in the Brazilian Amazon, Mamirauá (being managed for more than 12 years) and Amanã (initiating a management process), through the record of 485 fish landings in one fishing community in each reserve during high and low water seasons in 2003. Our goals were, first, to make a rapid and comparative assessment of some main aspects of fisheries in these two communities (fish species caught, CPUE, fishing gear and habitats exploited). Second, we used such data to evaluate if management strategies already in place in Mamirauá would be also valid for Amanã. Third, we compared fishing CPUE between the two communities, in order to check if co-management measures have contributed, at least partially, to preclude over-fishing, maintaining a higher fishing reward in Mamirauá reserve. We analyzed fisheries directed to the two most important marketable fishes in the region: the pirarucu (Arapaimas gigas) and the tambaqui (Colossoma macropomum), besides those fisheries aimed to subsistence and lower valued fishes. Our results indicated that the tambaqui was intensively fished year-round in Mamirauá, while Amanã fishers caught a higher variety of fishes, including catfishes and migratory scale fishes. Such differences might reflect differences in gear used and habitat exploited by fishers during the high water season. Mamirauá fishers caught a higher fish biomass considering both marketable and all fishes. Differences in gear used, habitats exploited and fishes caught during high water season indicate that distinct management initiatives might apply for each reserve. Notwithstanding their differences, both communities exploited the commercial fishes (tambaqui and pirarucu) in a similar way during the low water season. Therefore, the higher mean fishing yield (CPUE) observed in Mamirauá may be partially attributable to co-management measures, considering that Mamirauá has possibly been experiencing a higher fishing intensity than Amanã. Fishing related data are seldom available in Brazil and other tropical developing countries. We thus provided a framework of fast assessment of fishing dynamics, which may represent a first and useful step for management initiatives in the absence of more detailed data.