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51.
The transdermal permeation and metabolic characteristics of methyl nicotinate (MN) in stratum corneum and split-thickness human skin and three species of shed snake and snake skin (Elaphae obsoleta, Naja kaouthia, and Python molurus bivittatus) were evaluated. In vitro skin transport using excised skin and hydrolysis experiments using skin homogenate were carried out. The flux of MN, a metabolite, nicotinic acid (NA), and the total (MN+NA), as well as kinetic parameters (V(max) and K(m)) for hydrolysis of MN were determined and compared among various skin types. The total flux from MN-saturated solution through human skin was not significantly different from that through snake and shed snake skin of Elaphae obsoleta, Naja kaouthia but was significantly higher than that through snake and shed snake skin of Naja kaouthia (p < 0.05). A great difference in skin esterase activity was observed between human and snake in both snake skin and shed snake skin of all species. In all skins except the stratum corneum of human skin, NA flux increased with an increase in MN donor concentration and reached a plateau, suggesting that metabolic saturation was taking place in the skin. NA flux at the plateau and MN donor concentrations at which the NA flux reached a plateau also varied by species. These findings indicated that the discrepancy in transdermal profiles of MN among skins tested was predominantly due to the difference in the esterase activity in the skin.  相似文献   
52.
Five metabolites, ( Z)-6-benzylidene-3-hydroxymethyl-1,4-dimethyl-3-methylsulfanylpiperazine-2,5-dione ( 1), (3S,3'R)-3-(3'-hydroxybutyl)-7-methoxyphthalide ( 2), ( S)-3-butyl-7-methoxyphthalide ( 3), (3R,6R)-bisdethiodi(methylthio)hyalodendrin ( 4), and bis- N-norgliovictin ( 5), were isolated from the culture broth of the marine derived fungus of the order Pleosporales strain CRIF2. Compounds 1 and 2 are new fungal metabolites, while 3 was isolated for the first time as a natural product. Compounds 1, 3, and 4 exhibited only weak cytotoxic activity, while 5 was inactive at 50 microg/mL.  相似文献   
53.
ContextCordyceps militaris and Isaria tenuipes (Cordycipitaceae) are high-value fungi that are used for health-promoting food supplements. Since laboratory cultivation has begun for these fungi, increased output has been achieved.ObjectiveThis study compared the chemical profiles, antioxidant, anti-tyrosinase, and skin extracellular matrix degradation inhibition between mycelium and fruiting body of C. militaris and I. tenuipes.Materials and methodsThe antioxidative potential of 10% v/v aqueous infused extract from each fungus was separately investigated using 2,2-azinobis(3-ethylbenzo-thiazoline-6-sulphonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant ability, and ferric thiocyanate methods. The inhibition against MMP-1, elastase, and hyaluronidase were determined to reveal their anti-wrinkle potential. Anti-tyrosinase activities were determined.ResultsC. militaris and I. tenuipes extracts were found to contain a wide range of bioactive compounds, including phenolics, flavonoids, and adenosine. A correlation was discovered between the chemical compositions and their biological activities. The extract from I. tenuipes fruiting body (IF) was highlighted as an extraordinary elastase inhibitor (IC50 = 0.006 ± 0.004 mg/mL), hyaluronidase inhibitor (IC50: 30.3 ± 3.2 mg/mL), and antioxidant via radical scavenging (ABTS IC50: 0.22 ± 0.02 mg/mL; DPPH IC50: 0.05 ± 0.02 mg/mL), thereby reducing ability (EC1: 95.3 ± 4.8 mM FeSO4/g extract) and lipid peroxidation prevention (IC50: 0.40 ± 0.11 mg/mL). IF had a three-times higher EC1 value than ascorbic acid and significantly higher elastase inhibition than epigallocatechin gallate.Discussion and conclusionsIF is proposed as a powerful natural extract with antioxidant and anti-wrinkle properties; therefore, it is suggested for further use in pharmaceutical, cosmeceutical, and nutraceutical industries.  相似文献   
54.
Muscle regeneration occurs through activation of quiescent satellite cells whose progeny proliferate, differentiate, and fuse to make new myofibers. We used a transgenic Pax7-ZsGreen reporter mouse to prospectively isolate stem cells of skeletal muscle by flow cytometry. We show that Pax7-expressing cells (satellite cells) in the limb, head, and diaphragm muscles are homogeneous in size and granularity and uniformly labeled by certain cell surface markers, including CD34 and CD29. The frequency of the satellite cells varies between muscle types and with age. Clonal analysis demonstrated that all colonies arising from single cells within the Pax7-sorted fraction have myogenic potential. In response to injury, Pax7(+) cells reduce CD34, CD29, and CXCR4 expression, increase in size, and acquire Sca-1. When directly isolated and cultured in vitro, Pax7(+) cells display the hallmarks of activation and proliferate, initially as suspension aggregates and later distributed between suspension and adherence. During in vitro expansion, Pax7 (ZsGreen) and CD34 expression decline, whereas expression of PSA-NCAM is acquired. The nonmyogenic, Pax7(neg) cells expand as Sca1(+) PDGRalpha(+) PSA-NCAM(neg) cells. Satellite cells expanded exclusively in suspension can engraft and produce dystrophin(+) fibers in mdx(-/-) mice. These results establish a novel animal model for the study of muscle stem cell physiology and a culture system for expansion of engraftable muscle progenitors.  相似文献   
55.
OBJECTIVE: To evaluate the outcome and quality of in-hospital cardiopulmonary resuscitation (CPR), and factors affecting the outcome. SETTING: A 2300-bed university hospital in Thailand. METHOD: A 1-year prospective audit according to the Utstein style. RESULTS: A total of 639 cardiac arrests (370 male, 269 female, age 1 day-96 years, mean+/-S.D.=53.3+/-24.12 years) were included. Four hundred and thirty-three cardiac arrests (67.8%) occurred in non-monitored areas and 200 (31.3%) occurred in monitored areas. Five hundred and thirty-six cardiac arrests (84%) were witnessed. The majority of cardiac arrests occurred in medical patients (68.4%) and surgical patients (21.4%). The most common underlying causes of arrest were respiratory failure (24.7%) and septic shock (23.3%). Initial ECG rhythms were ventricular fibrillation 79 (12.4%), asystole 272 (42.6%) with pulseless electrical activity 225 (35.2%). Most patients received basic life support within 1 min (86.7%) and advanced life support (ALS) within 4 min (92.6%) but only 25% of patients received defibrillation within 3 min. Following resuscitation, 394 (61.7%) achieved restoration of spontaneous circulation and 44 patients (6.9%) survived to discharge. Only 162 post-arrest patients were treated in the critical care area. The initial survival rate was not associated with sex, age and time to ALS, but was significantly related to the monitored area. CONCLUSION: In our setting, survival to discharge is 6.9%. Initial survival rate was strongly associated with being in a monitored area. Defibrillators and the critical care areas were insufficient.  相似文献   
56.
OBJECTIVES: To examine the associations of residual endogenous estradiol (E2) to bone mineral density (BMD) and lipid concentrations in elderly women. METHODS: Subjects consisted of 59 elderly postmenopausal women with vertebral or femoral osteoporosis. BMD was measured at L2-4 and femoral neck by dual-energy X-ray absorptiometry (DEXA). Residual E2 concentrations were assessed by a sensitive radioimmunoassay. Data were expressed as mean +/- S.E.M. RESULTS: The age of the subjects was 65.2 +/- 0.8 years with 18.9 +/- 1.0 years postmenopausal. The mean residual E2 concentration was 6.0 +/- 0.5 pg/ml. There was a correlation between E2 levels and BMD at L2-4 (r = 0.32, P < 0.01) while no association was found at the femoral neck. The association between E2 and L2-4 BMD persisted after adjusting for years since menopause and body weight (r = 0.33, P < 0.05). With regard to serum lipid concentrations, no association of serum total cholesterol, LDL-cholesterol, HDL-cholesterol or triglyceride concentrations with residual E2 was found. CONCLUSIONS: Our findings confirm the role of residual endogenous E2 in the determination of bone mass in postmenopausal women with osteoporosis. The effect of residual E2 appears to be skeletal specific and possess no association with serum lipid concentrations.  相似文献   
57.
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59.

Purpose

Postoperative pain management is essential in the perioperative care of neonates and infants but it requires a high level of care. Wound infiltration with bupivacaine, a long-acting local anesthetic, is a simple method with minimal complications. However, studies on the effectiveness of wound infiltration in neonates and infants are lacking. The purpose of this study was to investigate the effectiveness of wound infiltration with bupivacaine for postoperative analgesia in neonates and infants undergoing abdominal surgery.

Methods

A prospective, randomized controlled trial was conducted in 34 neonates and infants. The patients were randomized into two groups: the bupivacaine (B) group and the control (C) group. A standardized anesthetic protocol was used for each patient. Before wound closure, the surgical site of each patient in the B group was infiltrated with 2?mg/kg of bupivacaine, whereas no surgical site anesthetic infiltration was used in the C group. The neonatal infant pain scale (NIPS) score was used to evaluate postoperative pain, and fentanyl 0.5–1.5?μg/kg was administered when the NIPS score was ≥4. In regard to the fentanyl requirement, the NIPS score and the numbers of patients whose NIPS score was ≥4 were compared between the two groups.

Results

The median fentanyl dose requirements in the B group and C group were 1 and 0.5?μg/kg, respectively; and the difference was not statistically significant (p?=?0.255). The postoperative NIPS scores in the two groups were not significantly different. In addition, there were no significant differences in the numbers of patients whose NIPS score was ≥4 at 6, 12, 18, and 24?h postoperatively.

Conclusions

In neonates and infants, wound infiltration with bupivacaine had no significant effect on pain relief or fentanyl requirement during the first 24?h after major abdominal surgery.  相似文献   
60.
A Trp64Arg mutation in the beta3-adrenergic receptor gene has been implicated in the pathophysiology of non-insulin-dependent diabetes mellitus and obesity. However, the findings have been controversial due to the use of different populations and different methods for the estimation of body fat. In the present study, the prevalence of Trp64Arg mutation of the beta3-adrenergic receptor gene was determined and its relation to body fat as assessed by dual-energy x-ray absorptiometry (DEXA) was evaluated in Thai men and women. The effect on insulin sensitivity as assessed by the serum insulin to glucose ratio was also examined. The subjects were 76 men and 135 women aged 20 to 80 years. Body fat and its regional distribution were assessed by DEXA. Mutation in the beta3-adrenergic receptor gene was determined by polymerase chain reaction (PCR)-restriction fragment length polymorphism. Data are expressed as the mean +/- SEM. Fifty-nine subjects (28.0%) had the Trp64Arg mutation in the beta3-adrenergic receptor gene; 54 (25.6%) were heterozygotes and five (2.4%) were homozygotes. The gene frequency of Trp64Arg mutation was 15.2% in these subjects. In women, Trp64Arg mutation was not associated with the difference in total body fat (Trp/Arg or Arg/Arg, 19.4 +/- 1.0 kg; Trp/Trp, 19.2 +/- 0.6 kg) or percent body fat (Trp/Arg or Arg/Arg, 34.6% +/- 1.2%; Trp/Trp, 34.3% +/- 0.6%). In contrast to the findings in women, men with Trp64Arg mutation had lower total body fat after controlling for age (Trp/Arg or Arg/Arg, 13.2 +/- 1.1 kg; Trp/Trp, 15.8 +/- 0.7 kg; P < .05). However, no difference was found in percent body fat (Trp/Arg or Arg/Arg, 20.9% +/- 1.3%; Trp/Trp, 23.3% +/- 0.7%). No difference in the fasting insulin resistance index (FIRI) was found between subjects with and without Trp64Arg mutation. The data suggest that Trp64Arg mutation of the beta3-adrenergic receptor is common in Thais and appears to exert effects on total body fat but not percent body fat in men. Trp64Arg mutation is not associated with insulin resistance as assessed by the FIRI in Thais.  相似文献   
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