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61.
Osorio A Vara-Thorbeck R Rosell J Osorio C Ortega E Ruiz-Requena E 《World journal of surgery》2002,26(9):1079-1082
We selected 38 patients scheduled for
cholecystectomy and studied their serum concentrations of
dehydroepiandrosterone (DHEA) and growth axis hormones [growth
hormone/insulin-like growth factor-1 (GH/IGF-1)]. We aimed to
determine whether alterations in these concentrations resulted from
surgical stress or, on the contrary, preceded surgery and were
themselves a cause of chronic diseases that reduce life expectancy. We
measured the serum concentrations of DHEA sulfate (DHEA-S), ACTH,
cortisol, human GH (hGH), IGF-1, and IGF-1 binding protein-3 (IGFBP-3)
preoperatively and then 2 and 7 days after surgery; we also compared
the preoperative findings with those of a healthy control group. The
results were analyzed by gender because DHEA and GH/IGF-1 are known to
present sexual dimorphism. There were no significant differences
between the preoperative and control results for any of the parameters
studied. We found a significant reduction in the concentrations of
DHEA-S and IGF-1 on days 2 and 7 after surgery versus the preoperative
values. We conclude that the decrease in DHEA-S in patients after
surgery is a result of surgical trauma and does not precede surgical
stress. The decrease in hormone levels observed in patients with
chronic disease may therefore be a result, not a cause, of disease, as
some have claimed. Further studies with a later endpoint would be of
interest to assess any subsequent return of DHEA-S levels to baseline
measurements. 相似文献
62.
Lladó I Rodríguez-Cuenca S Pujol E Monjo M Estrany ME Roca P Palou A 《Obesity research》2002,10(4):296-305
OBJECTIVE: To investigate the effects of short-term (15 days) cafeteria-diet feeding on the expression of alpha- and beta-adrenergic receptors (AR) and its association with lipolytic stimulation in isolated retroperitoneal white adipocytes. RESEARCH METHODS AND PROCEDURES: Six female and 6 male Wistar rats (4 weeks old) were fed a cafeteria diet plus standard diet for 15 days. The remaining 12 age- and sex-matched rats received a standard diet only. White retroperitoneal adipose tissue was isolated and used for the determination of both alpha(2) and beta-AR expression and for in vitro studies of lipolytic activity. RESULTS: In female control rats, we found higher lipolytic capacities located at the postreceptor level and a lower alpha(2)/beta(3)-AR ratio than male rats. Cafeteria-diet feeding for 15 days decreased lipolytic activity in both male and female rats and altered the alpha(2A)- and beta(3)-AR protein levels with an increase of alpha(2A)-AR in males and a beta(3)-AR decrease in females. DISCUSSION: Our results indicate that a 15-day cafeteria-diet feeding induced an increase in the alpha(2)/beta(3)-AR balance and impaired adipose tissue lipolytic activity, which was higher in males and may contribute to the development of increased fat mass. The higher functionality of alpha(2)-AR, together with the minor role developed by beta(3)-AR and lower lipolytic capacities located at the postreceptor level in cafeteria-diet-fed male rats compared with female rats, may be responsible for the gender-dependent differences observed in this study. 相似文献
63.
We investigated the local anesthetic action on ionic membrane conductance (membrane conductance) and selectivity in membranes formed with neuronal phospholipids in the absence and presence of cholesterol. In membranes without cholesterol, 1 mM bupivacaine and ropivacaine increased the membrane conductance approximately 4.5-fold; and 5 mM lidocaine, ropivacaine and bupivacaine increased the membrane conductance by 2.7-, 2.8- and 22.2-fold, respectively. In the presence of cholesterol, 5 mM ropivacaine had no effect, lidocaine decreased the membrane conductance by 2-fold, and bupivacaine increased the membrane conductance by 17-fold. Local anesthetics did not affect the ion selectivity in membranes without cholesterol, but they all decreased the Na(+) selectivity in membranes with cholesterol. Cholesterol reduced the lidocaine- and ropivacaine-induced membrane conductance increase by eliminating or reversing the Na(+) conductance increase and by lowering the Cl(-) conductance increase. In the absence of cholesterol, 5 mM bupivacaine increased both Na(+) conductance (38-fold) and Cl(-) conductance (19-fold), while in the presence of cholesterol it only increased Cl(-) conductance (26-fold). Of the local anesthetics studied, ropivacaine was the least membrane toxic while bupivacaine was the most toxic. 相似文献
64.
Photorejuvenation of facial skin with topical 20% 5-aminolevulinic acid and intense pulsed light treatment: a split-face comparison study 总被引:12,自引:0,他引:12
BACKGROUND: Photorejuvenation of facial skin has been reported after intense pulsed light (IPL) therapy alone and in conjunction with topical 5-aminolevulinic acid (5-ALA), but no comparative studies between these regimens have been performed. OBJECTIVE: To evaluate the safety and effectiveness of combination topical 5-ALA and IPL compared to IPL treatment alone. METHODS: Ten patients with mild to moderate photodamage were randomly assigned treatment with 5-ALA + IPL on one facial half and IPL alone on the contralateral side. Two treatments were delivered at 4-week intervals. Clinical improvement scores were determined by masked evaluations of digital photographs obtained at baseline, prior to each treatment session, and at 1, 3, and 6 months after the final treatment. RESULTS: Higher clinical improvement scores were noted on the combination 5-ALA + IPL treated areas. Mild edema, erythema, and desquamation were observed on the facial halves where 5-ALA was applied. No scarring or unwanted pigmentary alteration was seen. CONCLUSIONS: Photodynamic therapy with combination topical 5-ALA + IPL is safe and more effective for facial rejuvenation than IPL treatment alone. 相似文献
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70.
Natural inhibitors of carcinogenesis 总被引:10,自引:0,他引:10
Kinghorn AD Su BN Jang DS Chang LC Lee D Gu JQ Carcache-Blanco EJ Pawlus AD Lee SK Park EJ Cuendet M Gills JJ Bhat K Park HS Mata-Greenwood E Song LL Jang M Pezzuto JM 《Planta medica》2004,70(8):691-705
Previous collaborative work by our group has led to the discovery of several plant isolates and derivatives with activities in in vivo models of cancer chemoprevention, including deguelin, resveratrol, bruceantin, brassinin, 4'-bromoflavone, and oxomate. Using a panel of in vitro bioassays to monitor chromatographic fractionation, a diverse group of plant secondary metabolites has been identified as potential cancer chemopreventive agents from mainly edible plants. Nearly 50 new compounds have been isolated as bioactive principles in one or more in vitro bioassays in work performed over the last five years. Included among these new active compounds are alkaloids, flavonoids, stilbenoids, and withanolides, as well as a novel stilbenolignan and the first representatives of the norwithanolides, which have a 27-carbon atom skeleton. In addition, over 100 active compounds of previously known structure have been obtained. Based on this large pool of potential cancer chemopreventive compounds, structure-activity relationships are discussed in terms of the quinone reductase induction ability of flavonoids and withanolides and the cyclooxygenase-1 and -2 inhibitory activities of flavanones, flavones and stilbenoids. Several of the bioactive compounds were found to be active when evaluated in a mouse mammary organ culture assay, when used as a secondary discriminator in our work. The compounds (2 S)-abyssinone II, (2 S)-2',4'-dihydroxy-2"-(1-hydroxy-1-methylethyl)dihydrofuro[2,3- h]-flavanone, 3'-[gamma-hydroxymethyl-( E)-gamma-methylallyl]-2,4,2',4'-tetrahydroxychalcone 11'- O-coumarate, isolicoflavonol, isoliquiritigenin, and ixocarpalactone A are regarded as promising leads as potential cancer chemopreventive agents. 相似文献