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231.
Cristiane Gonçalves Titto João Alberto Negrão Evaldo Antonio Lencioni Titto Taissa de Souza Canaes Rafael Martins Titto Alfredo Manuel Franco Pereira 《International journal of biometeorology》2013,57(2):299-306
Access to an evaporative cooling system can increase production in dairy cows because of improved thermal comfort. This study aimed to evaluate the impact of ambient temperature on thermoregulation, plasma cortisol, insulin-like growth factor 1 (IGF-I), and productive status, and to determine the efficiency of an evaporative cooling system on physiological responses under different weather patterns. A total of 28 Holstein cows were divided into two groups, one with and the other without access to a cooling system with fans and mist in the free stall. The parameters were analyzed during morning (0700 hours) and afternoon milking (1430 hours) under five different weather patterns throughout the year (fall, winter, spring, dry summer, and rainy summer). Rectal temperature (RT), body surface temperature (BS), base of tail temperature (TT), and respiratory frequency (RF) were lower in the morning (P?<?0.01). The cooling system did not affect RT, and both the groups had values below 38.56 over the year (P?=?0.11). Cortisol and IGF-I may have been influenced by the seasons, in opposite ways. Cortisol concentrations were higher in winter (P?<?0.05) and IGF-I was higher during spring-summer (P?<?0.05). The air temperature and the temperature humidity index showed positive moderate correlations to RT, BS, TT, and RF (P?<?0.001). The ambient temperature was found to have a positive correlation with the physiological variables, independent of the cooling system, but cooled animals exhibited higher milk production during spring and summer (P?<?0.01). 相似文献
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Alessandro Lentini Alberto Abbruzzese Bruno Provenzano Claudio Tabolacci Simone Beninati 《Amino acids》2013,44(1):25-32
The ability to metastasize represents the most important characteristic of malignant tumors. The biological details of the metastatic process remain somewhat unknown, due to difficulties in studying tumor cell behaviour with high spatial and temporal resolution in vivo. Several lines of evidence involve transglutaminases (TGs) in the key stages of tumor progression cascade, even though the molecular mechanisms remain controversial. TG expression and activity display a different role in the primary tumor or in metastatic cells. In fact, TG expression is low in the primary tumor mass, but augmented when cells acquire the metastatic phenotype. Nevertheless, in other cases, the use of inducers of TG transamidating activity seems to contrast tumor cell plasticity, migration and invasion. In the following review, the function of TGs in cancer cell migration into the extracellular matrix, adhesion to the capillary endothelium and its basement membrane, invasion and angiogenesis is discussed. 相似文献
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236.
Federico Mussano Alberto Bartorelli Cusani Alessia Brossa Stefano Carossa Gianni Bussolati 《Bioscience, biotechnology, and biochemistry》2013,77(4):662-671
New approaches in the treatment of skeletal defects may benefit from the use of soluble biological factors. We previously standardized a derivative of bovine colostrum (SBCD), deprived of casein and fat and rich in cytokines. In the present study, we tested its possible use as an adjuvant in bone healing. SBCD contained factors involved in stromal cell stimulation and differentiation and induced cytokine production from stimulated mesenchymal stem cells (MSCs). In vitro, SBCD promoted proliferation, migration and, in association with osteogenic factors, osteogenic differentiation of osteoblastic and MSCs. In in vivo experiments of subcutaneous Matrigel injection in mice, SBCD plus hydroxyapatite, but not hydroxyapatite nor SBCD alone, induced recruitment of macrophages and stromal cells. After 60?days, plugs containing SBCD and hydroxyapatite were densely calcified and diffusely positive for osteocalcin, supporting the occurrence of an early osteogenic process. These results indicate that SBCD is a rich source of factors with osteoinductive properties. 相似文献
237.
Alvaro C. Ucero Alberto Benito-Martin Isabel Fuentes-Calvo Beatriz Santamaria Julia Blanco Jose M. Lopez-Novoa Marta Ruiz-Ortega Jesus Egido Linda C. Burkly Carlos Martinez-Salgado Alberto Ortiz 《生物化学与生物物理学报:疾病的分子基础》2013,1832(10):1744-1755
Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) regulates apoptosis, proliferation and inflammation in renal epithelial cells and plays a role in acute kidney injury. However, there is little information on the chronic effects of TWEAK. We hypothesized that TWEAK may influence renal fibrosis and regulate kidney fibroblast biology, in part, through Ras pathway.We studied a chronic model of experimental unilateral ureteral obstruction in wild type and TWEAK deficient mice, and a murine model of systemic TWEAK overexpression. TWEAK actions were also explored in cultured renal and embryonic fibroblasts.TWEAK and TWEAK receptor expression was increased in the obstructed kidneys. The absence of TWEAK decreased early kidney tubular damage, inflammatory infiltrates and myofibroblast number. TWEAK deficient mice had decreased renal fibrosis 21 days after obstruction, as assessed by extracellular matrix staining. In mice without prior underlying kidney disease, systemic overexpression of TWEAK induced kidney inflammation and fibrosis. In cultured fibroblasts, TWEAK induced proliferation through activation of the Ras/ERK pathway. TWEAK also activated nuclear factor κB (NFκB)-dependent inflammatory chemokine production in murine renal fibroblasts.In conclusion, lack of TWEAK reduces renal fibrosis in a model of persistent kidney insult and overexpression of TWEAK led to renal fibrosis. TWEAK actions on renal fibroblasts may contribute to the in vivo observations, as TWEAK promotes inflammatory activity and proliferation in fibroblast cultures. 相似文献
238.
Biniam T. Maru Magda Constanti Alberto M. Stchigel Francesc Medina Jesus E. Sueiras 《Biotechnology progress》2013,29(1):31-38
Glycerol is an attractive substrate for biohydrogen production because, in theory, it can produce 3 mol of hydrogen per mol of glycerol. Moreover, glycerol is produced in substantial amounts as a byproduct of producing biodiesel, the demand for which has increased in recent years. Therefore, hydrogen production from glycerol was studied by dark fermentation using three strains of bacteria: namely, Enterobacter spH1, Enterobacter spH2, and Citrobacter freundii H3 and a mixture thereof (1:1:1). It was found that, when an initial concentration of 20 g/L of glycerol was used, all three strains and their mixture produced substantial amounts of hydrogen ranging from 2400 to 3500 mL/L, being highest for C. freundii H3 (3547 mL/L) and Enterobacter spH1 (3506 mL/L). The main nongaseous fermentation products were ethanol and acetate, albeit in different ratios. For Enterobacter spH1, Enterobacter spH2, C. freundii H3, and the mixture (1:1:1), the ethanol yields (in mol EtOH/mol glycerol consumed) were 0.96, 0.67, 0.31, and 0.66, respectively. Compared to the individual strains, the mixture (1:1:1) did not show a significantly higher hydrogen level, indicating that there was no synergistic effect. Enterobacter spH1 was selected for further investigation because of its higher yield of hydrogen and ethanol. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013 相似文献
239.
Carlos Alberto Pires Pereira Alexandre R. Marra Luis Fernando Aranha Camargo Ant?nio Carlos Campos Pignatari Teresa Sukiennik Paulo Renato Petersen Behar Eduardo Alexandrino Servolo Medeiros Julival Ribeiro Evelyne Gir?o Luci Correa Carla Guerra Irna Carneiro Carlos Brites Marise Reis Marta Antunes de Souza Regina Tranchesi Cristina U. Barata Michael B. Edmond Brazilian SCOPE Study Group 《PloS one》2013,8(7)
Background
Nosocomial bloodstream infections (nBSIs) are an important cause of morbidity and mortality and are the most frequent type of nosocomial infection in pediatric patients.Methods
We identified the predominant pathogens and antimicrobial susceptibilities of nosocomial bloodstream isolates in pediatric patients (≤16 years of age) in the Brazilian Prospective Surveillance for nBSIs at 16 hospitals from 12 June 2007 to 31 March 2010 (Br SCOPE project).Results
In our study a total of 2,563 cases of nBSI were reported by hospitals participating in the Br SCOPE project. Among these, 342 clinically significant episodes of BSI were identified in pediatric patients (≤16 years of age). Ninety-six percent of BSIs were monomicrobial. Gram-negative organisms caused 49.0% of these BSIs, Gram-positive organisms caused 42.6%, and fungi caused 8.4%. The most common pathogens were Coagulase-negative staphylococci (CoNS) (21.3%), Klebsiella spp. (15.7%), Staphylococcus aureus (10.6%), and Acinetobacter spp. (9.2%). The crude mortality was 21.6% (74 of 342). Forty-five percent of nBSIs occurred in a pediatric or neonatal intensive-care unit (ICU). The most frequent underlying conditions were malignancy, in 95 patients (27.8%). Among the potential factors predisposing patients to BSI, central venous catheters were the most frequent (66.4%). Methicillin resistance was detected in 37 S. aureus isolates (27.1%). Of the Klebsiella spp. isolates, 43.2% were resistant to ceftriaxone. Of the Acinetobacter spp. and Pseudomonas aeruginosa isolates, 42.9% and 21.4%, respectively, were resistant to imipenem.Conclusions
In our multicenter study, we found a high mortality and a large proportion of gram-negative bacilli with elevated levels of resistance in pediatric patients. 相似文献240.
Martin Czerny Ilan Barchichat Katharina Meszaros Gottfried H. Sodeck Alberto Weber David Reineke Lars Englberger Florian Sch?nhoff Alexander Kadner Hansj?rg Jenni Jürg Schmidli Thierry P. Carrel 《PloS one》2013,8(3)