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361.
Joana Micael Armindo S. Rodrigues Maria C. Barreto Maria J. Alves Malcolm B. Jones Ana C. Costa 《Invertebrate reproduction & development.》2013,57(4):205-216
The reproductive cycle of Ophidiaster ophidianus (strictly protected status) from São Miguel Island, in the Azorean Archipelago was studied. The reproductive strategy; the energy allocation of each sex during the reproductive cycle and the nutritional condition of the population were analyzed. Gonadal index (GI) showed a clear seasonal pattern with spawning between August and October but histological examination revealed that gamete release can occur throughout the entire year. The pyloric caeca index (PCI) showed little annual variation but with an inverse relationship with the GI. Allocation of energy to the gonads and to the pyloric caeca reflected the seasonal reproductive strategy of this species. Individuals were able to simultaneously develop gonads, pyloric caeca, and quickly regenerate lost arms. There was a major expenditure of energy by females compared to males but, sexual size dimorphism was not observed. The reproductive pattern observed in O. ophidianus combining rich food availability and seawater temperatures characteristic of a temperate zone may be the key to the success of this species in the Azorean oceanic Island. 相似文献
362.
363.
Prada PO Pauli JR Ropelle ER Zecchin HG Carvalheira JB Velloso LA Saad MJ 《FEBS letters》2006,580(20):4889-4894
A high-fat diet (HFD) is associated with reduced glucose uptake in muscle, but not in adipose tissue. In the present study, we investigated whether a HFD can modulate glucose uptake in adipose tissue by increasing signal transduction through the CAP/Cbl pathway, independently of the PI3-K/Akt pathway. Our results suggest that, in HFD, the differential regulation of insulin-induced glucose uptake between skeletal muscle and adipose tissue may, in part, be a consequence of the CAP/Cbl/C3G pathway, since the expression of CAP and Cbl, and also the activation of this pathway were increased in adipose tissue but not in muscle. 相似文献
364.
Cazarolli LH Zanatta L Jorge AP de Sousa E Horst H Woehl VM Pizzolatti MG Szpoganicz B Silva FR 《Chemico-biological interactions》2006,163(3):177-191
The present study sought to evaluate the hypoglycemic activities of free glycosylated flavonoids and flavonoid complexes with vanadium(IV), (VO(IV)), on glycemia in experimental diabetic rats. Besides free kaempferol-3,7-O-(alpha)-dirhamnoside and kaempferol-3-neohesperidoside, complexes of these flavonoids with VO(IV) were administered by different routes in order to compare the potency of the compounds as well as the efficacy of insulin or VO(IV) in lowering serum glucose. Wistar rats were made diabetic by alloxan. The glycemia was assessed at different times after the administering of compounds. The equilibrium constants were determined by potentiometric study and two species with VO(IV) are proposed at physiological pH, VOH(2)L(2) for kaempferitrin and VOHL for kaempferol-3-neohesperidoside. The latter exhibited hypoglycemic activity at all times examined with 50 and 100 mg/kg and the former reduced the glycemia from 0 to 6h by i.p. route. The administering of the complexes or 0.0146 mmol/kg VO(IV) resulted in a serum glucose-lowering effect over time in the case of i.p. treatment. A marked hypoglycemic effect was observed for 0.5IU of insulin (67.5%); 0.0146 mmol VO(IV) (16.8%); 0.0294 mmol kaempferitrin-VO(IV) (17.8%) and 0.0286 mmol kaempferol-3-neohesperidoside-VO(IV) (56.0%) at 3h after i.p. treatment when compared with respective zero time in diabetic groups. Kaempferol-3-neohesperidoside-VO(IV) was 2.5 times more effective than VO(IV), twice as effective as the free compound and three times more effective than kaempferitrin-VO(IV). This is of particular interest since kaempferol-3-neohesperidoside appears to represent a suitable ligand for VO(IV) to mimic the efficacy of insulin in lowering serum glucose levels. 相似文献
365.
Silva AF Carvalho G Oehmen A Lousada-Ferreira M van Nieuwenhuijzen A Reis MA Crespo MT 《Applied microbiology and biotechnology》2012,93(5):2171-2180
Membrane bioreactors (MBR) are an important and increasingly implemented wastewater treatment technology, which are operated
at low food to microorganism ratios (F/M) and retain slow-growing organisms. Enhanced biological phosphorus removal (EBPR)-related
organisms grow slower than ordinary heterotrophs, but have never been studied in detail in MBRs. This study presents a comprehensive
analysis of the microorganisms involved in EBPR in pilot- and full-scale MBRs, using fluorescence in situ hybridization (FISH),
as well as an overall assessment of other relevant microbial groups. The results showed that polyphosphate accumulating organisms
(PAOs) were present at similar levels in all studied MBRs (10% ± 6%), even those without a defined anaerobic zone. Glycogen
accumulating organisms were also detected, although rarely. The FISH results correlated well with the observed P removal performance
of each plant. The results from this study suggest that a defined anaerobic zone is not necessarily required for putative
PAO growth in MBRs, since polyphosphate storage may provide a selective advantage in fulfilling cell maintenance requirements
in substrate-limited conditions (low F/M). 相似文献
366.
Sampaio FG Boijink Cde L Bichara Dos Santos LR Oba ET Kalinin AL Luiz AJ Rantin FT 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2012,156(3-4):178-186
This study investigated the potentially detrimental effects of copper and elevated aquatic CO(2) (hypercarbia), alone or in combination, on pacu, Piaractus mesopotamicus. Fish were exposed for 48h to control (no copper addition in normocarbia), to 400μg Cu(2+)L(-1), to hypercarbic (1% CO(2); PCO(2)=6.9mm Hg) water and to 400μg Cu(2+)L(-1)+hypercarbia. In liver the single factors caused an increase in lipid hydroperoxide concentration that was not observed when the factors were combined. Copper exposure elicited increased hepatic superoxide dismutase activity, irrespective of aquatic CO(2) level. On the other hand, the effects of copper on hepatic glutathione peroxidase activity were dependent on water CO(2) levels. The two stressors combined did not affect hepatic catalase activity. Hypercarbic water caused a decline in plasma glucose concentration, but this was not observed when hypercarbia was combined with copper exposure. Copper caused a decrease in branchial Na(+)/K(+)-ATPase activity that was independent of water CO(2) level. Copper caused an increase in branchial metallothionein concentration that was independent of water CO(2) level. Thus, branchial metallothionein and Na(+)/K(+)-ATPase were effective biomarkers of copper exposure that were not affected by water CO(2) level. 相似文献
367.
Ummanni R Barreto F Venz S Scharf C Barett C Mannsperger HA Brase JC Kuner R Schlomm T Sauter G Sültmann H Korf U Bokemeyer C Walther R Brümmendorf TH Balabanov S 《Journal of proteome research》2012,11(4):2452-2466
The present study aimed to investigate the proteome profiling of surgically treated prostate cancers. Hereto, 2D-DIGE and mass spectrometry were performed for protein identification, and data validation for peroxiredoxin 3 and 4 (PRDX3 and PRDX4) was accomplished by reverse phase protein arrays (RPPA). The Formal Concept Analysis (FCA) method was applied to assess whether the TMPRSS2-ERG gene fusion could influence the degree of overexpression of PRDX3 and PRDX4 in prostate cancer. Lastly, we performed an in vitro functional characterization of both PRDX3 and PRDX4 using the classical human prostate cancer cell lines DU145 and LNCaP. Reverse phase protein arrays verified that the overexpression of both PRDX3 and PRDX4 in tumor samples is negatively correlated with the presence of the TMPRSS2-ERG gene fusion. Functional characterization of PRDX3 and PRDX4 activity in PCa cell lines suggests a role of these members of the peroxiredoxin family in the pathophysiology of this tumor entity. 相似文献
368.
Bianca V. Marins Gilberto M. Amado‐Filho Maria B. B. Barreto Leila L. Longo 《Phycological Research》2012,60(1):51-60
Two endemic species of Laminaria, Laminaria abyssalis Joly & Oliveira Filho and L. brasiliensis Joly & Oliveira Filho, from the tropical southwestern Atlantic coast have been described. The aim of this work was to determine the conspecificity of these species based on morphological and molecular analyses (ribulose 1,5‐bisphosphate carboxylase/oxgenase, large subunit (rbcL), internal transcribed spacer (ITS) and cytochrome c oxidase subunit I (coxI)). We found an overlap between the morphological characters that are considered taxonomically important for distinguishing these two species; these characters included a differing pattern of blade splitting. In the three molecular analyses, the Brazilian Laminaria specimens were grouped into one clade with maximum support. These data support the hypothesis that the individuals analyzed represent only one species, L. abyssalis. The molecular analysis also showed L. abyssalis to be sister group to L. digitata. 相似文献
369.
PY Boelle L Viviani PF Busson H Olesen S Ravilly M Stern B Assael C Barreto P Drevinek M Thomas U Krivec M Mei-Zahav JF Vibert A Clement A Mehta H Corvol 《Orphanet journal of rare diseases》2012,7(1):64
ABSTRACT: BACKGROUND: The clinical course of Cystic Fibrosis (CF) is usually measured using the percent predicted FEV1 and BMI Z-score referenced against a healthy population, since achieving normality is the ultimate goal of CF care. Referencing against age and sex matched CF peers may provide valuable information for patients and for comparison between CF centers or populations. Here, we used a large database of European CF patients to compute CF specific reference equations for FEV1 and BMI, derived CF-specific percentile charts and compared these European data to their nearest international equivalents. METHODS: 34859 FEV1 and 40947 BMI observations were used to compute European CF specific percentiles. Quantile regression was applied to raw measurements as a function of sex, age and height. Results were compared with the North American equivalent for FEV1 and with the WHO 2007 normative values for BMI. RESULTS: FEV1 and BMI percentiles illustrated the large variability between CF patients receiving the best current care. The European CF specific percentiles for FEV1 were significantly different from those in the USA from an earlier era, with higher lung function in Europe. The CF specific percentiles for BMI declined relative to the WHO standard in older children. Lung function and BMI were similar in the two largest contributing European Countries (France and Germany). CONCLUSION: The CF specific percentile approach applied to FEV1 and BMI allows referencing patients with respect to their peers. These data allow peer to peer and population comparisons in CF patients. 相似文献
370.
Jackie Dolan Karen Walshe Samantha Alsbury Karsten Hokamp Sean O'Keeffe Tatsuya Okafuji Suzanne FC Miller Guy Tear Kevin J Mitchell 《BMC genomics》2009,10(1):1-3
Correction to Dolan J, Walshe K, Alsbury S, Hokamp K, O'Keeffe S, Okafuji T, Miller SF, Tear G, Mitchell KJ: The extracellular leucine-rich repeat superfamily; a comparative survey and analysis of evolutionary relationships and expression patterns. BMC Genomics 2007, 8:320. 相似文献