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991.
Effects of a p38 MAP kinase inhibitor on bone ingrowth and tissue differentiation in rabbit chambers
Goodman SB Ma T Spanogle J Chiu R Miyanishi K Oh K Plouhar P Wadsworth S Smith RL 《Journal of biomedical materials research. Part A》2007,81(2):310-316
The effects of an oral p38 mitogen-activated protein kinase (MAPK) inhibitor and polyethylene particles separately and together on tissue differentiation in the bone harvest chamber (BHC) in rabbits over a 3-week treatment period were investigated. The harvested tissue was analyzed histomorphometrically for markers of bone formation (percentage of bone area), osteoblasts (alkaline phosphatase staining), and osteoclasts (CD51, the alpha chain of the vitronectin receptor). Polyethylene particles decreased the percentage of bone ingrowth and staining for alkaline phosphatase. The p38 MAPK inhibitor alone decreased alkaline phosphatase staining. When the oral p38 MAPK inhibitor was given and the chamber contained polyethylene particles, there was a suppression of bone ingrowth and alkaline phosphatase staining. In contrast to oral non-steroidal anti-inflammatory drugs (NSAIDs) and local Interleukin-1 receptor antagonist (IL-1ra) administration, the oral p38 MAPK inhibitor alone did not suppress bone formation when given during the initial phase of tissue differentiation. Particle-induced inflammation and the foreign body reaction were not curtailed when the p38 MAPK inhibitor was given simultaneously with particles. Additional experiments are needed to establish the efficacy of p38 MAPK inhibitor administration on mitigating an established inflammatory and foreign body reaction that parallels the clinical situation more closely. 相似文献
992.
Klein CE Chiu YL Awni W Zhu T Heuser RS Doan T Breitenbach J Morris JB Brun SC Hanna GJ 《Journal of acquired immune deficiency syndromes (1999)》2007,44(4):401-410
Lopinavir, an HIV protease inhibitor, is coformulated with ritonavir to enhance the bioavailability and pharmacokinetics of lopinavir. The original solid oral formulation of lopinavir/ritonavir, a soft-gelatin capsule (SGC), requires refrigerated storage, is taken as 6 capsules daily at the recommended adult dose, and is administered with food to maximize the bioavailability of lopinavir. Melt extrusion technology was used to produce a tablet formulation reducing the number of dosage units administered per day and simplifying storage requirements. Three studies assessed the bioavailability of tablet doses of lopinavir/ritonavir at 800/200 mg or 400/100 mg under different meal conditions compared with equal doses of the SGC after a moderate-fat meal. The tablet was bioequivalent to the SGC after a moderate-fat meal with respect to lopinavir and ritonavir areas under the concentration-time curve. Compared with the SGC formulation, the tablet formulation resulted in more consistent lopinavir and ritonavir exposures within and across studies and across meal conditions. The diminished food effect and decreased variability of the tablet are likely to result in more consistent lopinavir and ritonavir exposures, minimizing the likelihood of extreme high or low values compared with the SGC. 相似文献
993.
Objective: To investigate the prevalence and occupational risk factors of neck and upper limb disorders among secondary school teachers.
Methods: One hundred secondary schools in Hong Kong were randomly chosen. Every full-time teacher received a questionnaire and a letter
describing the purpose of the study. Questionnaires were collected 1 to 3 weeks later. Results: Among 3,100 secondary school teachers, the lifelong prevalence of neck pain and upper limb pain was 69.3% (2091/3018) and 35.8% (1088/3042) respectively. The lifelong
cumulative incidence of both neck and upper limb pain was 31.6% (938/2966). Multiple logistic regression analysis showed that
gender, age and working in head down posture were identified as risk factors for neck and upper limb pain. High workload,
low colleague support and high anxiety were found to be significant on affecting the neck pain and upper limb pain developed
after becoming teachers. Conclusions: Neck pain and upper limb pain were highly prevalent in secondary school teachers in Hong Kong. Gender, age, head down posture
and some psychological factors were found to be significant risk factors. 相似文献
994.
Chang WH Chen CM Hu SP Kan NW Chiu CC Liu JF 《Asia Pacific journal of clinical nutrition》2007,16(4):609-615
The aim of this study was to evaluate the effect of the consumption of purple sweet potato leaves (PSPLs) on the immune response and the modulation of that response in 15 basketball players during a training period. They completed the 7-week study consisted of a run-in period (week 1), a PSPLs diet (200 g PSPLs/d; weeks 2, 3), a washout period (weeks 4, 5), and a control diet (low polyphenols content and carotenoid content adjusted to the same level as that of PSPLs diet; weeks 6 and 7). Blood, urine, and saliva samples were collected for biochemical analysis. The results showed that the plasma polyphenols concentration increased significantly in the PSPLs period. Compared with the control period, the PSPLs consumption produced a significant increase in the proliferation responsiveness of peripheral blood mononuclear cells (PBMC), cytotoxic activity of nature killer (NK) cells, and secretion of interferon (IFN)-gamma. However, no significant increase in the secretion of salivary immunoglobulin A (sIgA), interleukin (IL)-2, or interleukin-4 was observed after PSPLs consumption. In conclusion, consumption of a PSPLs diet for 2 weeks can modulate the immune response of basketball players during a training period. 相似文献
995.
Association between dietary glycemic index and age-related macular degeneration in nondiabetic participants in the Age-Related Eye Disease Study 总被引:1,自引:0,他引:1
BACKGROUND: Age-related macular degeneration (AMD) is the major cause of irreversible blindness. AMD appears to share several carbohydrate-related mechanisms and risk factors with diabetes-related diseases, including retinopathy and cardiovascular disease (CVD); however, to date, only one small study has addressed this issue. OBJECTIVE: The objective was to test the hypothesis that dietary glycemic index (dGI), which has been related to the risk of diabetes and CVD, is associated with the risk and severity of AMD in nondiabetic elderly populations. DESIGN: Dietary information was obtained from 4099 participants aged 55-80 y (56% women) in the Age-Related Eye Disease Study (AREDS). A total of 8125 eligible eyes at baseline were classified into 1 of 5 AMD groups according to the size and extent of drusen, the presence of geographic atrophy, and neovascular changes. We used a generalized estimating approach to evaluate the relations between dGI and risk and severity of AMD with eyes as the unit of analysis. RESULTS: Compared with eyes in the first quintile of dGI, eyes in the fourth and fifth quintiles had a significantly or suggestively higher risk of large drusen, geographic atrophy, and neovascularization. The multivariate-adjusted odds ratios (95% CIs) for the highest quintile were 1.42 (1.09, 1.84), 1.78 (0.81, 3.90), and 1.41 (0.95, 2.08), respectively, of which only the odds ratio for large drusen was significant. A significant positive relation between dGI and severity of AMD was also noted (P for trend < 0.001). There was a 49% increase in the risk of advanced AMD (geographic atrophy plus neovascularization) for persons with a dGI higher than the sex median (women: >or=77.9; men: >or=79.3). This result indicated that 20% of prevalent cases of AMD would have been eliminated if the AREDS participants consumed diets with a dGI below the median. CONCLUSION: The association between dGI and AMD from the AREDS cross-sectional analysis at baseline suggests that a reduction in the dGI, a modifiable risk factor, may provide a means of diminishing the risk of AMD. 相似文献
996.
997.
Jessica N. McAlpine MD Derek S. Chiu MSc Remi A. Nout MD David N. Church MD Pascal Schmidt BSc Stephanie Lam BSc Samuel Leung MSc Stefania Bellone PhD Adele Wong MD Sara Y. Brucker MD Cheng Han Lee MD Blaise A. Clarke MD David G. Huntsman MD Marcus Q. Bernardini MD Joanne Ngeow MD Alessandro D. Santin MD Paul Goodfellow PhD Douglas A. Levine MD Martin Köbel MD Stefan Kommoss MD Tjalling Bosse MD C. Blake Gilks MD Aline Talhouk PhD 《Cancer》2021,127(14):2409-2422
998.
BACKGROUND: The cytochrome P450 CYP2D6 enzyme debrisoquine 4-hydroxylase metabolizes many different classes of commonly used drugs, such as tricyclic antidepressants and neuroleptics. Genetic polymorphism of the CYP2D6 gene is responsible for pronounced interindividual and interracial differences in the metabolism of these drugs. The CYP2D6*10 allele and its variants are the most frequent alleles found in Orientals, and they are responsible for diminished debrisoquine 4-hydroxylase activity because of the presence of a C(188)-->T mutation in exon 1. METHODS: One hundred nineteen Hong Kong Chinese subjects were genotyped by means of allele-specific PCR, PCR, and restriction enzyme analysis for 10 CYP2D6 alleles (CYP2D6*1, *2, *4D, *5, *8/*14, *10A, *10B, *15, *16, and J9). RESULTS: CYP2D6*10B was the most prevalent allele, and CYP2D6*10/CYP2D6*10 was the most frequent genotype, representing 41.17% [corrected] of the population. CONCLUSIONS: There was no significant difference in the prevalence of the alleles analyzed between our study and the Chinese populations genotyped previously. This is the largest study in terms of the number of CYP2D6 alleles analyzed in an Oriental population and the first one conducted in a Hong Kong Chinese population. 相似文献
999.
1000.
BACKGROUND: As many as 50% of total hospital admissions are readmissions. Because the factors contributing to hospital readmission are multiple, and research findings are not conclusive, it is important for clinicians to gain an understanding of the key factors that contribute to readmission. OBJECTIVES:This study explores the factors contributing to hospital readmission and derives an explanatory model that can best identify characteristics of patients at high risk for hospital readmission. METHODS: This research was a case-controlled study with readmitted patients (n = 168) as the readmitted group and non-readmitted patients (n = 98) as the control group. The variables included demographic data, health assessment data, medical diagnosis, frequency of admissions, severity of illness, intensity of service and improvement of condition. The study sample was also interviewed to explore the patients' views on their repeated hospitalization. RESULTS: In the bivariate analysis significant differences between the study and control groups were multiple and generally consistent with findings in other studies. Using multiple logistic regression, however, the final model shows that only three factors best predict readmissions: frequency (3-4 times) of readmissions (OR = 9.96, p < .0001) and frequency (more than 5 times) of readmissions (OR = 15.73, p < .0001), financial assistance (OR = 5.03, p < .001), and severity of illness (OR = 3.12, p < .01). Our interview data suggest that the readmitted patients required assistance to accomplish daily living activities upon discharge and often returned to the hospital for the same health reason. CONCLUSION: The study findings suggest that patients who are frequently readmitted to the hospital are severely ill; are on public assistance; and may need special attention when discharged in order to attenuate repeated hospital readmission. 相似文献