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51.
Ponzo OJ Cresta MA Rondina D Szwarcfarb B Basabe JC Scacchi P 《Neuro endocrinology letters》2000,21(6):441-446
OBJECTIVE AND DESIGN: the objective of this study performed in adult male rats was to determine the alteration in glycemic, insulin and gonadotrophin luteinizing hormone secretion, and noradrenaline pancreatic concentration caused by fasting (F) and aproteic diet (Ap) during 7 and 21 days respectively, as well as the recovery after 24-hour refeeding with control diet (Co). RESULTS: a significant decrease in glycemic levels was only achieved through fasting (F: 86 +/- 5.1 mg %), when compared with controls (Co: 107 +/- 5 mg %). In spite of the high levels of carbohydrates (89%) present in the aproteic diet, the animals fed with this diet showed no differences in glycemic levels (Ap: 120.3 +/- 12.2 mg %), compared with controls. As a result of fasting and aproteic diet, there was a significant decrease in insulin (F: 8.67 +/- 1.36; Ap: 5.7 +/- 0.67; Co: 31 +/- 3.4 uU/ml) and LH levels (F: 10.175 +/- 1.74; Ap: 13.7 +/- 4; Co: 29.83 +/- 4.91 ng/ml). The refed recovered insulin (FR: 50.57 +/- 6.63; ApR: 43.5 +/- 6.85 uU/ml), but not LH levels (FR: 14.25 +/- 3.54; ApR: 13.03 +/- 4.25 ng/ml). A significant increase was observed in the pancreatic noradrenaline concentration (P<0.001) of rats receiving aproteic diet (889.9 +/- 34.65 ng/mg tissue) and fasting during 7 days (827.5 +/- 55.7 ng/mg tissue), compared with controls (531.1 +/- 48.6 ng/mg tissue). CONCLUSIONS: fasting and aproteic diets altered gonadal and metabolic control. When returning to a normal nutritional condition, only the metabolic control, not the reproductive function, could be recovered in the first 24 hours of refeeding. Malnutrition-induced hypoinsulinemia would be caused by an increase in a specific noradrenergic tone. 相似文献
52.
Antón DN 《Current microbiology》2000,40(1):72-77
Rapid growth of Salmonella typhimurium LT2 in rich LB-broth caused the induction of the cysteine regulon when the culture reached an optical density at 650 nm of
1.5. Addition of 0.05 mM L-cystine to LB-broth abolished induction, while 0.025 mM L-cystine delayed it for a doubling time
(30 min). Induction did not occur when lack of oxygen or a temperature shift to 19°C slowed down growth in LB-broth. Uninduced
cultures reached growth yield similar to that of induced cultures after overnight incubation. Growth on solid LB-medium also
brought about induction, but to a lower level than in liquid medium. Leaky cysB mutants, which are sensitive to the β-lactam antibiotic mecillinam, displayed partial induction, whereas mecillinam-resistant
cysB and cysE mutants showed no induction. It is suggested that induction develops in these mutants when constitutive transport systems
fail to satisfy the high uptake of cysteine demanded by fast-growing cultures. The behavior of cysB mutants agrees with the hypothesis that, under some conditions, mecillinam action would be dependent on expression of the
cysteine regulon.
Received: 9 June 1999 / Accepted: 11 August 1999 相似文献
53.
This study evaluated the use of a bile-salt-hydrolyzing Lactobacillus fermentum strain as a probiotic with potential hypocholesterolemic properties. The effect of L. fermentum on representative microbial populations and overall metabolic activity of the human intestinal microbiota was investigated using a three-stage continuous culture system. Also, the use of galactooligosaccharides as a prebiotic to enhance growth and/or activity of the Lactobacillus strain was evaluated. Administration of L. fermentum resulted in a decrease in the overall bifidobacterial population (ca. 1 log unit). In the in vitro system, no significant changes were observed in the total bacterial, Lactobacillus, Bacteroides, and clostridial populations through L. fermentum supplementation. Acetate production decreased by 9 to 27%, while the propionate and butyrate concentrations increased considerably (50 to 90% and 52 to 157%, respectively). A general, although lesser, increase in the production of lactate was observed with the administration of the L. fermentum strain. Supplementation of the prebiotic to the culture medium did not cause statistically significant changes in either the numbers or the activity of the microbiota, although an increase in the butyrate production was seen (29 to 39%). Results from this in vitro study suggest that L. fermentum KC5b is a candidate probiotic which may affect cholesterol metabolism. The short-chain fatty acid concentrations, specifically the molar proportion of propionate and/or bile salt deconjugation, are probably the major mechanism involved in the purported cholesterol-lowering properties of this strain. 相似文献
54.
Romeo Romagnoli Pier Giovanni Baraldi Olga Cruz-Lopez Carlota Lopez Cara Maria Dora Carrion Jan Balzarini Ernest Hamel Giuseppe Basso Roberta Bortolozzi Giampietro Viola 《Bioorganic & medicinal chemistry letters》2010,20(9):2733-2739
In a continuing study of hybrid compounds containing the α-bromoacryloyl moiety as potential anticancer drugs, we synthesized a novel series of hybrids 4a–h, in which this moiety was linked to a 1,5-diaryl-1,4-pentadien-3-one system. Many of the conjugates prepared (4b, 4c, 4e and 4g) demonstrated pronounced, submicromolar antiproliferative activity against four cancer cell lines. Moreover, compound 4b induced apoptosis through the mitochondrial pathway and activated caspase-3 in a concentration-dependent manner. 相似文献
55.
Al-Garawi A Husain M Ilieva D Humbles AA Kolbeck R Stampfli MR O'Byrne PM Coyle AJ Jordana M 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(2):832-843
Respiratory viral infections have been associated with an increased incidence of allergic asthma. However, the mechanisms by which respiratory infections facilitate allergic airway disease are incompletely understood. We previously showed that exposure to a low dose of house dust mite (HDM) resulted in enhanced HDM-mediated allergic airway inflammation, and, importantly, marked airway hyperreactivity only when allergen exposure occurred during an acute influenza A infection. In this study, we evaluated the impact of concurrent influenza infection and allergen exposure at the genomic level, using whole-genome microarray. Our data showed that, in contrast to exposure to a low dose of HDM, influenza A infection led to a dramatic increase in gene expression, particularly of TLRs, C-type lectin receptors, several complement components, as well as FcεR1. Additionally, we observed increased expression of a number of genes encoding chemokines and cytokines associated with the recruitment of proinflammatory cells. Moreover, HDM exposure in the context of an influenza A infection resulted in the induction of unique genes, including calgranulin A (S100a8), an endogenous damage-associated molecular pattern and TLR4 agonist. In addition, we observed significantly increased expression of serum amyloid A (Saa3) and serine protease inhibitor 3n (Serpina3n). This study showed that influenza infection markedly increased the expression of multiple gene classes capable of sensing allergens and amplifying the ensuing immune-inflammatory response. We propose that influenza A infection primes the lung environment in such a way as to lower the threshold of allergen responsiveness, thus facilitating the emergence of a clinically significant allergic phenotype. 相似文献
56.
57.
Fernanda Genre Raquel López-Mejías Mercedes García-Bermúdez Santos Casta?eda Carlos González-Juanatey Javier Llorca Alfonso Corrales Bego?a Ubilla José A. Miranda-Filloy Trinitario Pina Carmen Gómez-Vaquero Luis Rodríguez-Rodríguez Benjamín Fernández-Gutiérrez Alejandro Balsa Dora Pascual-Salcedo Francisco J. López-Longo Patricia Carreira Ricardo Blanco Isidoro González-álvaro Javier Martín Miguel A. González-Gay 《PloS one》2014,9(9)
Introduction
Rheumatoid arthritis is an inflammatory disease with high incidence of cardiovascular disease due to accelerated atherosclerosis. Osteoprotegerin (OPG) has been associated with increased risk of atherosclerotic disease in the general population. Several polymorphisms in the OPG gene with functional effects on cardiovascular disease in non-rheumatic individuals have been described. Therefore, we aimed to analyze the effect of three of these functional OPG polymorphisms on the risk of cardiovascular disease in a large and well-characterized cohort of Spanish patients with rheumatoid arthritis.Methods
Three OPG gene variants (rs3134063, rs2073618 and rs3134069) were genotyped by TaqMan assays in 2027 Spanish patients with rheumatoid arthritis. Anti-cyclic citrullinated peptide (anti-CCP) antibody testing was positive in 997 of 1714 tested. Also, 18.3% of the whole series had experienced cardiovascular events, including 5.4% with cerebrovascular accidents. The relationship between OPG variants and cardiovascular events was assessed using Cox regression.Results
No association between OPG gene variants and cardiovascular disease was observed in the whole group of rheumatoid arthritis patients or in anti-CCP positive patients. Nevertheless, a protective effect of CGA haplotype on the risk of cardiovascular disease in general, and specifically in the risk of cerebrovascular complications after adjusting for sex, age at disease diagnosis and traditional cardiovascular risk factors was disclosed in anti-CCP negative patients (HR = 0.54; 95%CI: 0.31–0.95; p = 0.032 and HR = 0.17; 95%CI: 0.04–0.78; p = 0.022, respectively).Conclusion
Our results indicate a protective effect of the OPG CGA haplotype on cardiovascular risk, mainly due to a protective effect against cerebrovascular events in anti-CCP negative rheumatoid arthritis patients. 相似文献58.
Josep M. Casacuberta Dora Raventós Pere Puigdoménech Blanca San Segundo 《Molecular & general genetics : MGG》1992,234(1):97-104
Summary The PRms protein is a pathogenesis-related (PR)-like protein whose mRNA accumulates during germination of maize seeds. Expression of the PRms gene is induced after infection of maize seeds with the fungus Fusarium moniliforme. To further our investigations on the expression of the PRms gene we examined the accumulation of PRms mRNA in different tissues of maize seedlings infected with E. moniliforme and studied the effect of fungal elicitors, the mycotoxin moniliformin, the hormone gibberellic acid, and specific chemical agents. Our results indicate that fungal infection, and treatment either with fungal elicitors or with moniliformin, a mycotoxin produced by F. monilforme, increase the steady-state level of PRms mRNA. PRms mRNA accumulation is also stimulated by the application of the hormone gibberellic acid or by treatment with silver nitrate, whereas acetylsalicylic acid has no effect. In situ RNA hybridization in isolated germinating embryo sections demonstrates that the PRms gene is expressed in the scutellum, particularly in a group of inner cells, and in the epithelium lying at the interface of the scutellum and the endosperm. The pattern of expression of the PRms gene closely resembles that found for hydrolytic enzymes, being confined to the scutellum and the aleurone layer of the germinating maize seed. Our results suggest that the PRms protein has a function during the normal process of seed germination that has become adapted to serve among the defence mechanisms induced in response to pathogens during maize seed germination. 相似文献
59.
Résumé Ce travail retrace les événements qui ont conduit à une collaboration exemplaire entre entomologistes enançais et américains (principalement le professeur C. V. Riley) pendant la crise du Phylloxera en France, grâce aux nombreuses archives existant de part et d’autre de I’Atlantique. Une des premiéres questions a été de savoir si le Phylloxera était identique dans les deux pays, prouvant ainsi son origine américaine. Une autre question a été de savoir si ce parasite était la cause ou la conséquence de la maladie de la vigne. Cette question, primordiale car lourde de conséquences sur les plans économique et politique, a vu s’afenonter certains entomologistes enançais (le professeur J. E. Planchon et J. Lichtenstein), tenant de I’hypothèse causale, à ?autres (V. A. Signoret) qui soutenaient que le puceron ne s’installait que sur des vignes malades. II s’est établi une collaboration remarquable entre les entomologistes enançais et C. V. Riley, qui a pu apporter des résultats très convaincants à la thèse causale. Enfin son rôle a été déterminant pour conforter la seule solution à long terme défendue par Planchon et Lichtenstein : la greffe de la vigne enançaise sur des vignes américaines résistantes. 相似文献
60.
Costa MF Oliveira AG Feitosa-Santana C Zatz M Ventura DF 《American journal of human genetics》2007,80(6):1064-1075
The present study evaluated the color vision of 44 patients with Duchenne muscular dystrophy (DMD) (mean age 14.8 years; SD 4.9) who were submitted to a battery of four different color tests: Cambridge Colour Test (CCT), Neitz Anomaloscope, Ishihara, and American Optical Hardy-Rand-Rittler (AO H-R-R). Patients were divided into two groups according to the region of deletion in the dystrophin gene: upstream of exon 30 (n=12) and downstream of exon 30 (n=32). The control group was composed of 70 age-matched healthy male subjects with no ophthalmological complaints. Of the patients with DMD, 47% (21/44) had a red-green color vision defect in the CCT, confirmed by the Neitz Anomaloscope with statistical agreement (P<.001). The Ishihara and the AO H-R-R had a lower capacity to detect color defects--5% and 7%, respectively, with no statistical similarity between the results of these two tests nor between CCT and Anomaloscope results (P>.05). Of the patients with deletion downstream of exon 30, 66% had a red-green color defect. No color defect was found in the patients with deletion upstream of exon 30. A negative correlation between the color thresholds and age was found for the controls and patients with DMD, suggesting a nonprogressive color defect. The percentage (66%) of patients with a red-green defect was significantly higher than the expected <10% for the normal male population (P<.001). In contrast, patients with DMD with deletion upstream of exon 30 had normal color vision. This color defect might be partially explained by a retina impairment related to dystrophin isoform Dp260. 相似文献