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71.
In a previous study, we established that leptin acts synergistically with interferon-gamma in inducing nitric oxide synthase type II in cultured chondrocytes via Janus kinase-2 activation. However, the exact molecular mechanism that accounts for this synergism is not completely understood. The aim of the present study was to further delineate the signalling pathway used by leptin/interferon-gamma in the nitric oxide synthase type II induction in chondrocytes. Consequently, the roles of PI-3 kinase, MEK1 and p38 kinase were investigated using specific pharmacological inhibitors (Wortmannin, LY 294002, PD 098,059 and SB 203580). For this purpose, the amount of stable nitrite, the end product of NO generation by activated chondrocytes, has been evaluated by Griess colorimetric reaction in culture medium of human primary chondrocytes and in the murine ATDC5 cell line stimulated with leptin (400 nM) and interferon-gamma (1 ng/ml), alone or in combination. Specific inhibitors for PI-3K, MEK1 and p38 were added 1 h before stimulation. Nitric oxide synthase type II mRNA was investigated by real-time RT-PCR and NOS type II protein expression has been evaluated by western blot analysis. Our results showed that, as expected, leptin synergizes with IFN-gamma in inducing NO accumulation in the supernatant of co-stimulated cells. Pre-treatment with Wortmannin, LY 294002, PD 098,059 and SB 203580 caused a significant decrease in nitrite production, NOS type II protein expression and NOS type II mRNA expression induced by leptin and interferon-gamma co-stimulation. These findings were confirmed in 15 and 21-day differentiated ATDC5 cells, and in normal human primary chondrocytes. This is the first report showing that NOS type II induction triggered by co-stimulation with leptin and interferon-gamma is mediated by a signaling pathway involving PI-3K, MEK1 and p38. 相似文献
72.
Plant phenology is in great measure driven by air temperature. To forecast harvest time for ‘Algerie’ loquat accurately, the
growing degree days (GDD) needed from bloom to ripening were determined using data from nine seasons. The methods proposed
by Zalom et al. (Zalom FG, Goodell PB, Wilson LT, Barnett WW, Bentley W, Degree-days: the calculation and use of heat units
in pest management, leaflet no 21373, Division Agriculture and Natural Resources, University of California 10 pp, 1983) were compared as regards their ability to estimate heat summation based on hourly records. All the methods gave remarkably
similar results for our cultivation area, although the double-sine method showed higher performance when temperatures were
low. A base temperature of 3°C is proposed for ‘Algerie’ loquat because it provides a coefficient of variation in GDD among
seasons of below 5%, and because of its compatibility with loquat growth. Based on these determinations, ‘Algerie’ loquat
requires 1,715 GDD from bloom to harvest; under our conditions this heat is accumulated over an average of 159 days. Our procedure
permits the ‘Algerie’ harvest date to be estimated with a mean error of 4.4 days (<3% for the bloom-harvest period). GDD summation
did not prove superior to the use of the number of calendar days for predicting ‘Algerie’ harvest under non-limiting growing
conditions. However, GDD reflects the developmental rate in water-stressed trees better than calendar days. Trees under deficit
irrigation during flower development required more time and more heat to ripen their fruits. 相似文献
73.
López-Martínez R Hernández-Hernández F Millán-Chiu BE Manzano-Gayosso P Méndez-Tovar LJ 《Revista iberoamericana de micología》2007,24(4):283-288
We present a study on the control and elimination of the fungi affecting the mummies specifically at the museum "El Carmen", in San Angel, Mexico City. Twelve analysed mummies presented an important deterioration attributed to colonizing fungi. The degree of fungal contamination and the efficacy of imazalil were evaluated. Two samplings were performed in order to isolate and identify the fungal genera, one for control and the other after the treatment. Isolation was done by the carpet-square technique and identification was performed by morphological features. Each sampling gave a total of 100 samples as follows: 17 from the air, 23 from the walls and 60 from the mummies. Samples were cultured on Sabouraud dextrose agar. From the first sampling a total of 649 colonies corresponding to 24 genera were obtained being the most frequent Penicillium, Cladophialophora and Aspergillus. From the second sampling, after the imazalil treatment, which was applied by means of lit candles containing the antifungal drug, 57 colonies were recovered, representing a 91.2% fungal reduction; 18 genera were eliminated. In spite of resistance showed by many Penicillium strains, the imazalil is an alternative drug for the control of fungal colonization on these studied materials. 相似文献
74.
Systemic inflammatory markers in patients with aortic sclerosis 总被引:1,自引:0,他引:1
Rugina M Caras I Jurcut R Jurcut C Serbanescu F Salageanu A Apetrei E 《Roumanian archives of microbiology and immunology》2007,66(1-2):10-16
The aim of the study was to evaluate several mediators of inflammation in patients with aortic sclerosis in relation to severity of cardiovascular disease. Serum level of cytokines, soluble intracellular adhesion molecule 1, matrix metalloproteinase (MMP) 2 and 9 and their tissue inhibitor TIMP-1, were measured by ELISA and MMPs activity by zymography in 51 aortic sclerosis patients. The increase in MMPs expression positively correlated with their gelatinase activity; also there was a positive correlation between MMP-9 and TIMP-1 serum levels. Moreover, IL-6 concentration positively correlated with both serum level and activity of MMP-9. The level of IL-6 and IL-1Ra were higher in patients with a great burden of atherosclerosis. Noteworthy, statistically significant higher levels of IL-6 were noticed for patients with coronary artery disease. There was a significant increase in IL-6 serum level as well as a significant decrease in IL-1Ra for patients with a history of myocardial infarction. A trend toward higher concentration of inflammatory mediators was noticed in relation to the increase in severity of the aortic valve disease. Our results support the hypothesis of an "inflammatory pattern" associated with AS pathology and suggest the persistence of a chronic inflammation in patients who experienced acute coronary events. 相似文献
75.
Marcelo De Franco Patrícia dos Santos Carneiro Luciana Carla Peters Francisca Vorraro Andrea Borrego Orlando Garcia Ribeiro Nancy Starobinas Wafa Koury Cabrera Olga Martinez Ibañez 《Mammalian genome》2007,18(4):263-269
Lines of mice were obtained by selective breeding for maximum (AIRmax) or minimum (AIRmin) acute inflammation. They present
distinct neutrophil influx and show frequency disequilibrium of the solute carrier family 11a member 1
(Slc11a1) alleles. This gene is involved in ion transport at the endosomes within macrophages and neutrophils, interfering in their
activation. Homozygous AIRmax and AIRmin sublines for the Slc11a1 gene were produced to examine the interaction of this gene with the acute inflammatory loci. The present work investigated
wound-healing traits in AIRmax and AIRmin mice, in F1 and F2 intercrosses, and in Slc11a1 sublines. Two-millimeter ear punches were made in the mice and hole closure was measured during 40 days. AIRmax mice demonstrated
significant tissue repair while AIRmin mice did not. Significant differences between the responses of male and female mice
were also observed. Wound-healing traits demonstrated a correlation with neutrophil influx in F2 populations. AIRmax
SS
showed higher ear-wound closure than AIRmax
RR
mice, suggesting that the Slc11a1
S allele favored ear tissue repair. QTL analysis has detected two inflammatory loci modulating ear wound healing on chromosomes
1 and 14. These results suggest the involvement of the acute inflammation modifier QTL in the wound-healing phenotype. 相似文献
76.
José M. Palma Francisca Sevilla Ana Jiménez Luis A. del Río Francisco J. Corpas Paz álvarez de Morales Daymi M. Camejo 《Annals of botany》2015,116(4):627-636
Background and Aims Pepper (Capsicum annuum) contains high levels of antioxidants, such as vitamins A and C and flavonoids. However, information on the role of these beneficial compounds in the physiology of pepper fruit remains scarce. Recent studies have shown that antioxidants in ripe pepper fruit play a key role in responses to temperature changes, and the redox state at the time of harvest affects the nutritional value for human consumption. In this paper, the role of antioxidant metabolism of pepper fruit during ripening and in the response to low temperature is addressed, paying particular attention to ascorbate, NADPH and the superoxide dismutase enzymatic system. The participation of chloroplasts, mitochondria and peroxisomes in the ripening process is also investigated.Scope and Results Important changes occur at a subcellular level during ripening of pepper fruit. Chloroplasts turn into chromoplasts, with drastic conversion of their metabolism, and the role of the ascorbate–glutathione cycle is essential. In mitochondria from red fruits, higher ascorbate peroxidase (APX) and Mn-SOD activities are involved in avoiding the accumulation of reactive oxygen species in these organelles during ripening. Peroxisomes, whose antioxidant capacity at fruit ripening is substantially affected, display an atypical metabolic pattern during this physiological stage. In spite of these differences observed in the antioxidative metabolism of mitochondria and peroxisomes, proteomic analysis of these organelles, carried out by 2-D electrophoresis and MALDI-TOF/TOF and provided here for the first time, reveals no changes between the antioxidant metabolism from immature (green) and ripe (red) fruits.Conclusions Taken together, the results show that investigation of molecular and enzymatic antioxidants from cell compartments, especially chloroplasts, mitochondria and peroxisomes, is a useful tool to study the physiology of pepper fruit, particularly in the context of expanding their shelf-life after harvest and in maintaining their nutritional value. 相似文献
77.
Emma Tham Anna Lindstrand Avni Santani Helena Malmgren Addie Nesbitt Holly?A. Dubbs Elaine?H. Zackai Michael?J. Parker Francisca Millan Kenneth Rosenbaum Golder?N. Wilson Ann Nordgren 《American journal of human genetics》2015,96(3):507-513
Through a multi-center collaboration study, we here report six individuals from five unrelated families, with mutations in KAT6A/MOZ detected by whole-exome sequencing. All five different de novo heterozygous truncating mutations were located in the C-terminal transactivation domain of KAT6A: : c.3116_3117 delCT, p.(Ser1039∗); c.3830_3831insTT, p.(Arg1278Serfs∗17); c.3879 dupA, p.(Glu1294Argfs∗19); c.4108G>T p.(Glu1370∗) and c.4292 dupT, p.(Leu1431Phefs∗8). An additional subject with a 0.23 MB microdeletion including the entire KAT6A reading frame was identified with genome-wide array comparative genomic hybridization. Finally, by detailed clinical characterization we provide evidence that heterozygous mutations in KAT6A cause a distinct intellectual disability syndrome. The common phenotype includes hypotonia, intellectual disability, early feeding and oromotor difficulties, microcephaly and/or craniosynostosis, and cardiac defects in combination with subtle facial features such as bitemporal narrowing, broad nasal tip, thin upper lip, posteriorly rotated or low-set ears, and microretrognathia. The identification of human subjects complements previous work from mice and zebrafish where knockouts of Kat6a/kat6a lead to developmental defects. NM_001099412.1相似文献
78.
Reduced dopamine and glutamate neurotransmission in the nucleus accumbens of quinpirole‐sensitized rats hints at inhibitory D2 autoreceptor function 下载免费PDF全文
79.
Chukwujindu M. A. Iwegbue Ufuoma A. Onyonyewoma Francisca I. Bassey Godwin E. Nwajei Bice S. Martincigh 《人类与生态风险评估》2015,21(2):338-357
Concentrations of 16 priority polycyclic aromatic hydrocarbons (PAHs) were determined in 40 brands of biscuits in the Nigerian market. The analyses were performed by gas chromatography-flame ionisation detection (GC-FID) after Soxhlet extraction of the sample with hexane/dichloromethane and clean-up of the extract. The concentrations of Σ16 PAHs in these biscuit samples were in the range of 35.7–645.3 μg kg?1, 75.9–490.7 μg kg?1, 91.5–537 μg kg?1, 18.4–522.2 μg kg?1, 123.5–393.8 μg kg?1, 167.2–880 μg kg?1, 136.5–316 μg kg?1, and 135.5–241.6 μg kg?1 for shortcake, digestives, cookies, shortbread, wafers, crackers, Pringles, and cabin, respectively. The concentrations of Σ8 carcinogenic PAHs in the samples ranged from not detected (nd)–323.3 μg kg?1, 15.7–138 μg kg?1, 9.7–312.9 μg kg?1, nd–331.7 μg kg?1, nd–220.9 μg kg?1, nd–53.3 μg kg?1, 18.4–56.6 μg kg?1, and 6.6–170.8 μg kg?1 for shortcake, digestives, cookies, shortbread, wafers, crackers, Pringles, and cabin, respectively. The margin of exposure (MOE), based on PAH8 as an indicator for the occurrence and effects of PAHs in food, was less than 10,000, the serious health effects value, in 30% and 8% of the brands for the child and adult scenarios, respectively. 相似文献
80.
Conde J Scotece M Gómez R López V Gómez-Reino JJ Lago F Gualillo O 《BioFactors (Oxford, England)》2011,37(6):413-420
Until the identification of leptin, the first adipokine discovered in 1994, adipose tissue was considered only as an energy storage tissue. However, it is now clear that adipose tissue is an endocrine/paracrine/autocrine organ, which plays a relevant role in physiopathology of several inflammatory diseases. Actually, it is mainly involved not only in the low-grade inflammatory status in obesity but also in other relevant inflammatory conditions and autoimmune disorders. In this review article, we discuss the main biological activities of leptin, adiponectin, lipocalin-2, resistin, and visfatin, as well as their contributions to certain inflammatory conditions. 相似文献