Effect of different resistance-training regimens on the WNT-signaling pathway

The purpose of the present study was to evaluate the effects of 8 weeks of strength and power training on the expression of genes related to the canonical WNT pathway and beta-catenin protein levels in physically active men. Twenty-five subjects (27.4 +/- A 4.6 years) were balanced based on their relative maximum strength in the squat exercise (squat 1RM/body mass) and randomly assigned to strength training (ST) (n = 10), power training (PT) (n = 10), and control (C) (n = 5) groups. The ST and the PT groups performed high and low intensity squats, respectively, thrice a week, for 8 weeks. Muscle biopsies from the vastus lateralis muscle were collected before and after the training period. Relative strength and power increased similarly in both ST and PT groups (P < 0.001). Fiber cross-sectional area also increased similarly in both ST and PT groups. Gene expression and beta-catenin protein expression levels were assessed by real-time PCR and Western blot. Certain genes were up-regulated in the ST group (WNT1: 6.4-fold, P < 0.0001; SFRP1: 3.3-fold, P < 0.0001 and LEF1: 7.3-fold, P < 0.0001) and also in the PT group (WNT1: 24.9-fold, P < 0.0001; SFRP1: 2.7-fold, P < 0.0001; LEF1: 34.1-fold, P < 0.0001 and Cyclin D1: 7.7-fold, P < 0.001). In addition, the expression of key WNT pathway genes was substantially more responsive to PT than to ST (WNT1: P < 0.0001; LEF1: P < 0.0001 and Cyclin D1: P < 0.001). Finally, the total beta-catenin protein content increased only in the PT group (P < 0.05). Our data indicate that a PT regimen triggers greater responses in key elements of the WNT pathway.

Double disruption of alpha(2A)- and alpha(2C)-adrenoceptors results in sympathetic hyperactivity and high-bone-mass phenotype

Evidence demonstrates that sympathetic nervous system (SNS) activation causes osteopenia via beta(2)-adrenoceptor (beta(2)-AR) signaling. Here we show that female mice with chronic sympathetic hyperactivity owing to double knockout of adrenoceptors that negatively regulate norepinephrine release, alpha(2A)-AR and alpha(2C)-AR(alpha(2A)/alpha(2C)-ARKO), present an unexpected and generalized phenotype of high bone mass with decreased bone resorption and increased formation. In alpha(2A)/alpha(2C)-ARKO versus wild-type (WT) mice, micro-computed tomographic (mu CT) analysis showed increased, better connected, and more plate-shaped trabeculae in the femur and vertebra and increased cortical thickness in the vertebra, whereas biomechanical analysis showed increased tibial and femoral strength. Tibial mRNA expression of tartrate-resistant acid phosphatase (TRACP) and receptor activator of NF-kappa B (RANK), which are osteoclast-related factors, was lower in knockout (KO) mice. Plasma leptin and brain mRNA levels of cocaine amphetamine-regulated transcript (CART), which are factors that centrally affect bone turnover, and serum levels of estradiol were similar between mice strains. Tibial beta(2)-AR mRNA expression also was similar in KO and WT littermates, whereas alpha(2A)-, alpha(2B)- and alpha(2C)-AR mRNAs were detected in the tibia of WT mice and in osteoblast-like MC3T3-E1 cells. By immunohistochemistry, we detected alpha(2A)-, alpha(2B)-, alpha(2C)- and beta(2)-ARs in osteoblasts, osteoclasts, and chondrocytes of 18.5-day-old mouse fetuses and 35-day-old mice. Finally, we showed that isolated osteoclasts in culture are responsive to the selective alpha(2)-AR agonist clonidine and to the nonspecific alpha-AR antagonist phentolamine. These findings suggest that beta(2)-AR is not the single adrenoceptor involved in bone turnover regulation and show that alpha(2)-AR signaling also may mediate the SNS actions in the skeleton. (c) 2011 American Society for Bone and Mineral Research.

Corrosion Versus Mechanical Tests for Indirect Detection of Alpha Prime Phase in UNS S32520 Super Duplex Stainless Steel

Alpha prime formation leads to material embrittlement and deterioration of corrosion resistance. In the present study, the mechanical and corrosion behavior of super duplex stainless steel UNS S32520 aged at 475 degrees C from 0.5 h to 1,032 h was evaluated using microhardness measurements, Charpy impact tests, electrochemical impedance spectroscopy, and cyclic polarization curves. The sensibility of these tests to the effects of alpha prime phase was investigated. The microhardness test showed a gradual increase in hardness with aging time, whereas the impact tests revealed losses of about 80% in the energy absorption capacity for the material aged for 12 h in comparison with the solution-annealed samples. The most responsive analysis was the impact test, which indirectly revealed the presence of this deleterious phase in samples aged for 0.5 h. The electrochemical impedance spectroscopy and polarization tests were not highly sensitive to the alpha prime phase unless these are present in large amounts in the stainless steel.

Endophytic bacteria in long-term in vitro cultivated axenic pineapple microplants revealed by PCR-DGGE

In vitro propagated plants are believed to be free of microbes. However, after 5 years of in vitro culture of pineapple plants, without evidence of microbial contamination, the use of culture-independent molecular approach [classifying heterogeneous nucleic acids amplified via universal and specific 16S rRNA gene by polymerase chain reaction (PCR)], and further analysis by denaturing gradient gel electrophoresis (DGGE) revealed endophytic bacteria in roots, young and mature leaves of such plants. The amplification of 16S rRNA gene (Bacteria domain) with the exclusion of the plant chloroplast DNA interference, confirmed the presence of bacterial DNA, from endophytic microorganisms within microplant tissues. PCR-DGGE analysis revealed clear differences on bacterial communities depending on plant organ. Group-specific DGGE analyses also indicated differences in the structures of Actinobacteria, Alphaproteobacteria and Betaproteobacteria communities in each part of plants. The results suggest the occurrence of a succession of bacterial communities colonizing actively the microplants organs. This study is the first report that brings together evidences that pineapple microplants, previously considered axenic, harbor an endophytic bacterial community encompassing members of Actinobacteria, Alphaproteobacteria and Betaproteobacteria group which is responsive to differences in organs due to plant development.

Photochemical heat-shock response in common bean leaves as affected by previous water deficit

The heat sensitivity of photochemical processes was evaluated in the common bean (Phaseolus vulgaris) cultivars A222, A320, and Carioca grown under well-watered conditions during the entire plant cycle (control treatment) or subjected to a temporal moderate water deficit at the preflowering stage (PWD). The responses of chlorophyll fluorescence to temperature were evaluated in leaf discs excised from control and PWD plants seven days after the complete recovery of plant shoot hydration. Heat treatment was done in the dark (5 min) at the ambient CO2 concentration. Chlorophyll fluorescence was assessed under both dark and light conditions at 25, 35, and 45 degrees C. In the dark, a decline of the potential quantum efficiency of photosystem II (PSII) and an increase in minimum chlorophyll fluorescence were observed in all genotypes at 45 degrees C, but these responses were affected by PWD. In the light, the apparent electron transport rate and the effective quantum efficiency of PSII were reduced by heat stress (45 degrees C), but no change due to PWD was demonstrated. Interestingly, only the A222 cultivar subjected to PWD showed a significant increase in nonphotochemical fluorescence quenching at 45 degrees C. The common bean cultivars had different photochemical sensitivities to heat stress altered by a previous water deficit period. Increased thermal tolerance due to PWD was genotype-dependent and associated with an increase in potential quantum efficiency of PSII at high temperature. Under such conditions, the genotype responsive to PWD treatment enhanced its protective capacity against excessive light energy via increased nonphotochemical quenching.

A role for ferritin in the antioxidant system in coffee cell cultures

Iron (Fe) is an essential nutrient for plants, but it can generate oxidative stress at high concentrations. In this study, Coffea arabica L. cell suspension cultures were exposed to excess Fe (60 and 240 mu M) to investigate changes in the gene expression of ferritin and antioxidant enzymes. Iron content accumulated during cell growth, and Western blot analysis showed an increase of ferritin in cells treated with Fe. The expression of two ferritin genes retrieved from the Brazilian coffee EST database was studied. CaFER1, but not CaFER2, transcripts were induced by Fe exposure. Phylogenetic analysis revealed that CaFER1 is not similar to CaFER2 or to any ferritin that has been characterised in detail. The increase in ferritin gene expression was accompanied by an increase in the activity of antioxidant enzymes. Superoxide dismutase, guaiacol peroxidase, catalase, and glutathione reductase activities increased in cells grown in the presence of excess Fe, especially at 60 mu M, while the activity of glutathione S-transferase decreased. These data suggest that Fe induces oxidative stress in coffee cell suspension cultures and that ferritin participates in the antioxidant system to protect cells against oxidative damage. Thus, cellular Fe concentrations must be finely regulated to avoid cellular damage most likely caused by increased oxidative stress induced by Fe. However, transcriptional analyses indicate that ferritin genes are differentially controlled, as only CaFER1 expression was responsive to Fe treatment.

The bacterial diversity in a Brazilian non-disturbed mangrove sediment

The bacterial diversity present in sediments of a well-preserved mangrove in Ilha do Cardoso, located in the extreme south of So Paulo State coastline, Brazil, was assessed using culture-independent molecular approaches (denaturing gradient gel electrophoresis (DGGE) and analysis of 166 sequences from a clone library). The data revealed a bacterial community dominated by Alphaproteobacteria (40.36% of clones), Gammaproteobacteria (19.28% of clones) and Acidobacteria (27.71% of clones), while minor components of the assemblage were affiliated to Betaproteobacteria, Deltaproteobacteria, Firmicutes, Actinobacteria and Bacteroidetes. The clustering and redundancy analysis (RDA) based on DGGE were used to determine factors that modulate the diversity of bacterial communities in mangroves, such as depth, seasonal fluctuations, and locations over a transect area from the sea to the land. Profiles of specific DGGE gels showed that both dominant (`universal` Bacteria and Alphaproteobacteria) and low-density bacterial communities (Betaproteobacteria and Actinobacteria) are responsive to shifts in environmental factors. The location within the mangrove was determinant for all fractions of the community studied, whereas season was significant for Bacteria, Alphaproteobacteria, and Betaproteobacteria and sample depth determined the diversity of Alphaproteobacteria and Actinobacteria.

Mass Spectrometric Analysis of a Cyclic 7,8-Butanoguanine Adduct of N-Nitrosopyrrolidine: Comparison to Other N-Nitrosopyrrolidine Adducts in Rat Hepatic DNA

The well established rat hepatocarcinogen N-nitrosopytrolidine (NPYR, 1) requires metabolic activation to DNA adducts to express its carcinogenic activity. Among the NPYR-DNA adducts that have been identified, the cyclic 7,8-butanoguanine adduct 2-amino-6,7,8,9-tetrahydro-9-hydroxypyrido[2,1-f]purine-4(3H)-one (6) has been quantified using moderately sensitive methods, but its levels have never been compared to those of other DNA adducts of NPYR in rat hepatic DNA. Therefore, in this study, we developed a sensitive new LC-ESI-MS/MS-SRM method for the quantitation of adduct 6 and compared its levels to those of several other NPYR-DNA adducts formed by different mechanisms. The new method was shown to be accurate and precise, with good recoveries and low fmol detection limits. Rats were treated with NPYR by gavage at doses of 46, 92, or 184 mg/kg body weight and sacrificed 16 h later. Hepatic DNA was isolated and analyzed for NPYR-DNA adducts. Adduct 6 was by far the most prevalent, with levels ranging from about 900-3000 mu mol/mol Gua and responsive to dose. Levels of adducts formed from crotonaldehyde, a metabolite of NPYR, were about 0.2-0.9 mu mol/mol dGuo, while those of adducts resulting from reaction with DNA of tetrahydrofuranyl-like intermediates were in the range of 0.01-4 mu mol/mol deoxyribonucleoside. The results of this study demonstrate that, among typical NPYR-DNA adducts, adduct 6 is easily the most abundant in hepatic DNA. Since previous studies have shown that it can be detected in the urine of NPYR-treated rats, the results suggest that it is a potential candidate as a biomarker for assessing human exposure to and metabolic activation of NPYR.

B-1 cells modulate oral tolerance in mice

Although the origin and functions of B-1 cells are controversial, they are considered as a cellular element of innate immunity due to their ability to produce natural autoantibodies of the IgM type. These antibodies are encoded by a relatively limited repertoire of V genes, and their resulting diversity is smaller than that produced by conventional B cells. B-1 cells constitute the larger fraction of B cells in the peritoneal cavity and migrate to non-specific inflammation sites. In addition, they contribute to the production of IgA antibodies in the intestinal lamina propria. It has been demonstrated that they participate in the induction and maintenance of peripheral tolerance. Herein, the participation of B-1 cells in inducing oral tolerance is evaluated. Unexpectedly, BALB/Xid mice, the animals deficient in B-1 cells, are not tolerized to OVA but instead are responsive to oral immunization. Conversely, BALB/c mice respond to oral tolerance to this antigen. We used these biological characteristics of these animals to investigate whether BA cells are involved in the induction of oral tolerance to OVA. Results show that B-1 cells from BALB/c mice, treated orally with OVA and adoptively transferred to BALB/Xid mice were able to suppress local hypersensitivity reaction and lymphoproliferative cellular response observed in BALB/.Xid mice. These data demonstrate that B-1 cells have regulatory properties and are involved in the induction of oral tolerance. (C) 2009 Elsevier B.V. All rights reserved.

Statin regulation of CYP3A4 and CYP3A5 expression

CYP3A4 and CYP3A5 are cytochrome P450 enzymes that are highly expressed in the liver and gut and metabolize endogenous compounds and xenobiotics. Statins are cholesterol-lowering drugs that are extensively metabolized by CYP3A4 and CYP3A5. The bioavailability of statins is affected by CYP3A4 and CYP3A5 and glucuronidases metabolism as well as uptake and efflux transporters that affect drug disposition. CYP3A4 and CYP3A5 variants have been demonstrated to influence the pharmacokinetics, efficacy and safety of statins. Inducers and inhibitors of CYP3A4 and CYP3A5 play an important role in reducing statin efficacy and increase the risk of adverse effects, respectively. Statins have been demonstrated to increase CYP3A expression in vitro, most likely because they are ligands to nuclear receptors (pregnane X receptor and constitutive androsterone receptor) that form heterodimers with retinoid X receptors and bind to responsive elements in the CYP3A4 and CYP3A5 promoter regions. This special report outlines the earlier studies on variability of response to statins owing to CYP3A variants and highlights findings on the induction of CYP3A4 and CYP3A5 expression by statins.

Transcript profiling of papaya fruit reveals differentially expressed genes associated with fruit ripening

Papaya (Carica papaya L) fruit has a short shelf life due to fast ripening induced by ethylene, but little is known about the genetic control of ripening and attributes of fruit quality. Therefore, we identified ripening-related genes affected by ethylene using cDNA-AFLP (Amplified Fragment Length Polymorphism of cDNA). Transcript profiling of non-induced and ethylene-induced fruit samples was performed, and 71 differentially expressed genes were identified. Among those genes some involved in ethylene biosynthesis, regulation of transcription, and stress responses or plant defence were found (heat shock proteins, polygalacturonase-inhibiting protein, and acyl-CoA oxidases). Several transcription factors were isolated, and except for a 14-3-3 protein, an AP2 domain-containing factor, a salt-tolerant zinc finger protein, and a suppressor of PhyA-105 1, most of them were negatively affected by ethylene, including fragments of transcripts similar to VRN1, and ethylene responsive factors (ERF). With respect to fruit quality, genes related to cell wall structure or metabolism, volatiles or pigment precursors, and vitamin biosynthesis were also found. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Variability in UVB Tolerances of Melanized and Nonmelanized Cells of Cryptococcus neoformans and C-laurentii

Solar radiation is one of the major factors responsible for the control of fungus populations in the environment. Inactivation by UVA and UVB radiation is especially important for the control of fungi that disperse infective units through the air, including fungi such as Cryptococcus spp. that infect their vertebrate hosts by inhalation. Cryptococcus neoformans produces melanin in the presence of certain exogenous substrates such as l-3,4 dihydroxyphenylalanine and melanization may protect the fungus against biotic and abiotic environmental factors. In the present study, we investigated the effect of exposure to an UVB irradiance of 1000 mW m(-2) (biologically effective weighted irradiance) on the survival of melanized and nonmelanized cells of four strains of C. neoformans and four strains of C. laurentii. The relative survival (survival of cells exposed to radiation in relation to cells not exposed) of cells grown 2, 4, 6 or 8 days on medium with or without L-dopa was determined after exposure to UVB doses of 1.8 and 3.6 kJ m(-2). Both the irradiance spectrum and the intensities of those doses are environmentally realistic, and, in fact, occur routinely during summer months in temperate regions. Differences in tolerance to UVB radiation were observed between the C. neoformans and C. laurentii strains. The C. neoformans strains were more susceptible to UVB radiation than the C. laurentii strains. In C. neoformans, differences in tolerance to radiation were observed during development of both melanized and nonmelanized cells. For most treatments (strain, time of growth and UVB dose), there were virtually no differences in tolerances between melanized and nonmelanized cells, but when differences occurred they were smaller than those previously observed with UVC. In tests with two strains of C. laurentii, there was no difference in tolerance to UVB radiation between melanized and nonmelanized cells during 8 days of culture; and in tests with four strains for less culture time (4 days) there were no significant differences in tolerance between melanized and nonmelanized cells of any strain of this species.

The isolation and characterization of virulence factors of Cryptococcus spp. from saprophytic sources in the city of Ribeirao Preto, Sao Paulo, Brazil

Yeasts of the Cryptococcus genus are distributed in nature associated to animal and vegetal organic residues. Occasionally, species other than C. neoformans may be responsible for infectious diseases in human and animals. This study aims to determine the occurrence of Cryptococcus species in the atmosphere and bird droppings in the city of Ribeirao Preto, Sao Paulo, Brazil, and to evaluate three virulence factors: capsule formation, growth at 37 degrees C and melanin production. We analyzed 86 environmental samples (54 droppings and 32 air). Of the 41 strains isolated, 15 were C. neoformans var. neoformans (12 droppings and 3 air), 15 C. albidus (12 droppings and 3 air), 9 C. laurentii (7 droppings and 2 air) and 2 C. uniguttulatus (from droppings). Capsules were produced by 93.3% of C. neoformans var. neoformans, 66.7% of C. albidus, 88.9% of C. laurentii and 50% (1/2) of C. uniguttulatus. All, strains of C. neoformans, 20% of C. albidus and 44.4% of C. laurentii were able to grow at 37 degrees C. The melanin production on DOPA agar was verified in C. neoformans (93.3%), C. albidus (26.7%) and C. laurentii (66.7%). We concluded that different Cryptococcus species coexist in the same ecological niche and they are able to produce virulence factors. (C) 2007 Elsevier GmbH. All rights reserved.

Evaluating Flexible Transport Solutions

Flexible transport services (FTS) have been of increasing interest in developed countries as a bridge between the use of personal car travel and fixed route transit services. This paper reports on findings from a recent study in Queensland Australia, which identified lessons from an international review and implications for Australia. Potential strategic directions, including a vision, mission, key result areas, strategies, and identified means of measuring performance are described. Evaluation criteria for assessing flexible transport proposals were developed, and approaches to identifying and assessing needs and demands outlined. The use of emerging technologies is also a key element of successful flexible transport services.

Evidence for persistent dysfunction of wild-type aldosterone synthase gene in glucocorticoid-treated familial hyperaldosteronism type I

Background In familial hyperaldosteronism type I (FH-I), glucocorticoid treatment suppresses adrenocorticotrophic hormone-regulated hybrid gene expression and corrects hyperaldosteronism. Objective To determine whether the wild-type aldosterone synthase genes, thereby released from chronic suppression, are capable of functioning normally. Methods We compared mid-morning levels of plasma potassium, plasma aldosterone, plasma renin activity (PRA) and aldosterone : PRA ratios, measured with patients in an upright position, and responsiveness of aldosterone levels to infusion of angiotensin II (AII), for 11 patients with FH-I before and during long-term (0.8-14.3 years) treatment with 0.25-0.75 mg/day dexamethasone or 2.5-10 mg/day prednisolone. Results During glucocorticoid treatment, hypertension was corrected in all. Potassium levels, which had been low (< 3.5 mmol/l) in two patients before treatment, were normal in all during treatment (mean 4.0 +/- 0.1 mmol/l, range 3.5-4.6). Aldosterone levels during treatment [13.2 +/- 2.1 ng/100 ml (mean +/- SEM)] were lower than those before treatment (20.1 +/- 2.5 ng/100 ml, P < 0.05). PRA levels, which had been suppressed before treatment (0.5 +/- 0.2 ng/ml per h), were unsuppressed during treatment (5.1 +/- 1.5 ng/ml per h, P < 0.01) and elevated (> 4 ng/ml per h) in six patients. Aldosterone : PRA ratios, which had been elevated (> 30) before treatment (101.1 +/- 25.9), were much lower during treatment (4.1 +/- 1.0, P < 0.005) and below normal (< 5) in eight patients. Surprisingly, aldosterone level, which had not been responsive (< 50% rise) to infusion of AII for all 11 patients before treatment, remained unresponsive for 10 during treatment. Conclusions Apparently regardless of duration of glucocorticoid treatment in FH-I, aldosterone level remains poorly responsive to AII, with a higher than normal PRA and a low aldosterone : PRA ratio. This is consistent with there being a persistent defect in functioning of wild-type aldosterone synthase gene. (C) Rapid Science Publishers ISSN 0263-6352.