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171.
Thomas P J Solomon Sakita N Sistrun Raj K Krishnan Luis F Del Aguila Christine M Marchetti Susan M O'Carroll Valerie B O'Leary John P Kirwan 《Journal of applied physiology》2008,104(5):1313-1319
Older, obese, and sedentary individuals are at high risk of developing diabetes and cardiovascular disease. Exercise training improves metabolic anomalies associated with such diseases, but the effects of caloric restriction in addition to exercise in such a high-risk group are not known. Changes in body composition and metabolism during a lifestyle intervention were investigated in 23 older, obese men and women (aged 66 +/- 1 yr, body mass index 33.2 +/- 1.4 kg/m(2)) with impaired glucose tolerance. All volunteers undertook 12 wk of aerobic exercise training [5 days/wk for 60 min at 75% maximal oxygen consumption (Vo(2max))] with either normal caloric intake (eucaloric group, 1,901 +/- 277 kcal/day, n = 12) or a reduced-calorie diet (hypocaloric group, 1,307 +/- 70 kcal/day, n = 11), as dictated by nutritional counseling. Body composition (decreased fat mass; maintained fat-free mass), aerobic fitness (Vo(2max)), leptinemia, insulin sensitivity, and intramyocellular lipid accumulation (IMCL) in skeletal muscle improved in both groups (P < 0.05). Improvements in body composition, leptin, and basal fat oxidation were greater in the hypocaloric group. Following the intervention, there was a correlation between the increase in basal fat oxidation and the decrease in IMCL (r = -0.53, P = 0.04). In addition, basal fat oxidation was associated with circulating leptin after (r = 0.65, P = 0.0007) but not before the intervention (r = 0.05, P = 0.84). In conclusion, these data show that exercise training improves resting substrate oxidation and creates a metabolic milieu that appears to promote lipid utilization in skeletal muscle, thus facilitating a reversal of insulin resistance. We also demonstrate that leptin sensitivity is improved but that such a trend may rely on reducing caloric intake in addition to exercise training. 相似文献
172.
173.
Agas D Marchetti L Menghi G Materazzi S Materazzi G Capacchietti M Hurley MM Sabbieti MG 《Journal of cellular physiology》2008,214(1):145-152
In this study, we investigated the role of prostaglandin F2alpha (PGF2alpha) in mouse osteoblast survival and the function of fibroblast growth factor 2 (FGF-2) and fibroblast growth factor receptor 1 (FGFR1) in this process. In particular, for the first time, we demonstrated that PGF2alpha increased osteoblast survival in a dose-dependent manner and we showed that the effect is correlated with an increase in Bcl-2/Bax ratio. Furthermore, we demonstrated that PGF2alpha caused a decrement of the active caspases 9 and 3. By blocking FGF-2 with the specific neutralizing antibody and by depletion of FGFR1 gene with a specific siRNA, we showed that FGFR1 and FGF-2 are critical for the increment of Bcl-2/Bax ratio and the decrement of the active caspases 9 and 3, induced by PGF2alpha. Moreover, transmission electron microscopy studies showed that PGF2alpha increased binding of FGF-2 and FGFR1 and co-localization of reactive sites at plasma membrane level. In conclusion, we report a novel mechanism in which PGF2alpha induces FGF-2 binding to its specific cell surface receptor 1 leading to a cascade pathway that culminates with increased mouse osteoblast survival. 相似文献
174.
Evaluation of the inhibitory effects of human serum components on bactericidal activity of human beta defensin 3 总被引:3,自引:1,他引:2
Maisetta G Di Luca M Esin S Florio W Brancatisano FL Bottai D Campa M Batoni G 《Peptides》2008,29(1):1-6
Naturally occurring cationic antimicrobial peptides (CAPs) are an essential component of the innate immune system of multicellular organisms. At concentrations generally higher than those found in vivo, most CAPs exhibit strong antibacterial properties in vitro, but their activity may be inhibited by body fluids, a fact that could limit their future use as antimicrobial and/or immunomodulatory agents. In the present study, we evaluated the effects of human serum components on bactericidal activity of the human beta-defensin 3 (hBD-3), a CAP considered particularly promising for future therapeutic employment. Human serum diluted to 20% strongly inhibited the bactericidal activity of the peptide against both the Gram-positive species Staphylococcus aureus and the Gram-negative species Acinetobacter baumannii. Such activity was not restored in serum devoid of salts (dialyzed), pre-treated with protease inhibitors, or subjected to both of these treatments. The addition of physiological concentrations of NaCl, CaCl2, and human albumin in the bactericidal assay abolished bactericidal activity of hBD-3 against S. aureus, while it only partially inhibited the activity of the peptide against A. baumannii. Although a proteolytic activity of serum on hBD-3 was demonstrated at the protein level by Western blot, addition of physiological concentrations of trypsin to the bactericidal assay only partially affected the antibacterial properties of the peptide. Altogether, these results demonstrate a major role of mono-divalent cations and serum proteins on inhibition of hBD-3 antibacterial properties and indicate a relative lack in sensitivity of the bactericidal activity of this peptide to trypsin and trypsin-like proteases. 相似文献
175.
The last part of the chimpanzee (Pan troglodytes) habituation process of the Ta? South Group was monitored over 2 years (1994-1996), during which all males and most of the females became habituated to observation by humans. The time needed (5-7 years) to habituate the community was similar to that recorded for the Ta? North Group and is comparable to other populations studied in Africa. Variation emerged in habituation rate: males were habituated earlier than females, and among females, sexually cycling individuals were habituated faster than non-cycling females. Such differences may be a function of both the methods used to find the chimpanzees and the sex of the individual. Reproductive status and individuality may also have influenced habituation rates by affecting the number of contacts required to habituate a chimpanzee to neutral humans. 相似文献
176.
Jasmonates Inhibit Flowering in Short-Day Plant Pharbitis nil 总被引:1,自引:0,他引:1
Beata Daria Maciejewska Jacek Kesy Marlena Zielińska Jan Kopcewicz 《Plant Growth Regulation》2004,43(1):1-8
The role of jasmonates in the photoperiodic flower induction of short-day plant Pharbitis nil was investigated. The plants were grown in a special cycle: 72 h of darkness, 24 h of white light with lowered intensity, 24-h long inductive night, 14 days of continuous light. At 4 h of inductive night the cotyledons of non-induced plants contained about two times the amount of endogenous jasmonates (JA/JA-Me) compared to those induced. A 15-min long pulse of far red light (FR) applied at the end of a 24-h long white light phase inhibited flowering of P. nil. The concentration of jasmonates at 2 and 4 h of inductive night in the cotyledons of the plants treated with FR was similar. Red light (R) could reverse the effect of FR. R light applied after FR light decreased the content of jasmonates by about 50%. Methyl jasmonate (JA-Me) applied to cotyledons, shoot apices and cotyledon petioles of P. nil inhibited the formation of flower buds during the first half of a 24-h long inductive or 14-h long subinductive night. Application of JA-Me to the cotyledons was the most effective. None of the plants treated with JA-Me on the cotyledons in the middle of the inductive night formed terminal flower buds. The aspirin, ibuprofen and phenidone, jasmonates biosynthesis inhibitors partially reversed the effect of FR, stimulating the formation of axillary and terminal flower buds. Thus, the results obtained suggests that phytochrome system control both the photoperiodic flower induction and jasmonates metabolism. Jasmonates inhibit flowering in P. nil. 相似文献
177.
Kusumoto R Dawut L Marchetti C Wan Lee J Vindigni A Ramsden D Bohr VA 《Biochemistry》2008,47(28):7548-7556
Werner syndrome is a rare human disease characterized by the premature onset of aging-associated pathologies, cancer predisposition, and genomic instability. The Werner protein (WRN), which is defective in Werner syndrome ( WS) patients, belongs to the RecQ family helicases and interacts with several DNA metabolic proteins, including DNA repair factors and telomere associated proteins. Nonhomologous end-joining (NHEJ) is an important pathway in the repair of DNA double strand breaks (DSBs), and the DNA-PK complex, composed of the heterodimer Ku 70/86 and the DNA-PK catalytic subunit (DNA-PKcs), together with the XRCC4-DNA ligase IV complex (X4L4), are major factors. One of the most prominent protein interactions of WRN is with Ku 70/86, and it is possible that WRN is involved in NHEJ via its associations with Ku 70/86 and DNA-PKcs. This study demonstrates that WRN physically interacts with the major NHEJ factor, X4L4, which stimulates WRN exonuclease but not its helicase activity. The human RecQ helicase, BLM, which possesses only helicase activity, does not bind to X4L4, and its helicase activity is not affected by X4L4. In a DNA end-joining assay, we find that a substrate, which is processed by WRN, is ligated by X4L4, thus further supporting the significance of their functional interaction. 相似文献
178.
In this study, we contrast brain morphology from hatchery and wild reared stocks to examine the hypothesis that in salmonid fishes, captive rearing produces changes in brain development. Using rainbow trout, Oncorhynchus mykiss, as a model, we measured eight regions of the salmonid brain to examine differences between wild and hatchery reared fish. We find using multiple analysis of covariance (MANCOVA), analysis of covariance (ANCOVA) and discriminant function analysis (DFA) that the brains of hatchery reared fish are relatively smaller in several critical measures than their wild counterparts. Our work may suggest a mechanistic basis for the observed vulnerability of hatchery fish to predation and their general low survival upon release into the wild. Our results are the first to highlight the effects of hatchery rearing on changes in brain development inbreak fishes. 相似文献
179.
Facts and fiction about long-term survival in tardigrades 总被引:4,自引:0,他引:4
180.
Design, synthesis, and SAR of heterocycle-containing antagonists of the human CCR5 receptor for the treatment of HIV-1 infection 总被引:1,自引:0,他引:1
Dooseop Kim Liping Wang Charles G. Caldwell Ping Chen Paul E. Finke Bryan Oates Malcolm MacCoss Sander G. Mills Lorraine Malkowitz Sandra L. Gould Julie A. DeMartino Martin S. Springer Daria Hazuda Michael Miller Joseph Kessler Renee Danzeisen Gwen Carver Anthony Carella Karen Holmes Janet Lineberger William A. Schleif Emilio A. Emini 《Bioorganic & medicinal chemistry letters》2001,11(24):1060-3106
Replacement of the large hydantoin-indole moiety from our previous work with a variety of smaller heterocyclic analogues gave rise to potent CCR5 antagonists having binding affinity comparable to the hydantoin analogues. The synthesis, SAR, and biological profiles of this class of antagonists are described. 相似文献