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101.
In vitro drug release studies remain indispensable in the development of drug delivery systems, even if correlations between in vitro and in vivo results are often imperfect. In this work, an improved in vitro analysis method for studying in situ-forming lipid-based implants was developed. More specifically, lipase was found to be an essential additive for evidencing differences in drug release kinetics from organogels of different amino acid-based organogelators, organogelator concentrations, drug loadings, and volumes. Lipases are thought to participate in the degradation of and release from amino acid-based organogel implants in vivo. Our experimental conditions allowed for the rapid and reliable screening of in vitro parameters that may be optimized to slow or accelerate drug release, once preliminary in vivo data are available.  相似文献   
102.

Background:

Cystic fibrosis (CF) is the most prevalent lethal autosomal recessive disease with a broad spectrum of phenotypes. Mutation of ΔF508 in the CFTR gene is the most important and lethal mutation in CF, which contains 70% of all predisposing mutations for CF worldwide.

Objectives:

Determining frequency of genotypes with ΔF508 mutation in CFTR gene, and evaluation of correlation between genotype and phenotype of Iranian patients with CF.

Patients and Methods:

Thirty six patients were included in this cross sectional study. ΔF508 mutations in both alleles of the CFTR gene were checked.

Results:

Among 36 pediatric patients, ΔF508 mutation was detected in 9 (25%) patients; 2 patients were heterozygous, and 7 patients homozygous for this mutation. From overall 72 tracked alleles, 11 (15.2%) were found to have ΔF508 mutations. Differences in prevalence of dyspnea and bronchiectasis were significant in homozygote group, compared with non-mutated group for ΔF508.

Conclusions:

It seems that more ΔF508 mutated alleles lead to more severe symptoms of CF.  相似文献   
103.
Introduction: Circulating fatty acids (FAs) may play a role in the disease pathogenesis of patients with systemic lupus erythematosus (SLE). Objectives: To compare red blood cell (RBC) and plasma FA composition: (1) between female SLE patients and age‐matched healthy female (HF) controls and in SLE with history of cardiovascular disease (CVD) and those with no history (SLE+CVD vs SLE–CVD); and (2) between SLE patients who were or were not receiving prednisone treatment at the time of blood sampling. Methods: This cross‐sectional study consisted of 33 female patients with SLE (11 SLE+CVD, 22 SLE?CVD) and 20 HF controls. Demographics, CVD risk, medication profile, blood biochemistry, and FA composition of RBC and plasma total lipids were determined. Results: Waist circumference and body mass index were higher in SLE patients than in HF controls. These variables along with serum triglycerides, blood glucose, and systolic blood pressure were higher in SLE+CVD than SLE?CVD patients. RBC FA composition showed lower eicosapentaenoic acid (EPA, ω‐3 active metabolite) and ω‐3 index (EPA+ docosahexaenoic acid) in SLE patients compared with HF controls. The ratio of the RBC inflammatory metabolite, arachidonic acid, to the anti‐inflammatory metabolite EPA was also significantly higher in SLE patients than in HF controls. No differences were seen in plasma FA between SLE and HF groups. However, SLE?CVD patients had a more favorable lipid profile than SLE+CVD patients. In SLE patients, the use of prednisone resulted in alteration of both RBC and plasma FA composition. Conclusion: SLE patients, regardless of their history of CVD, have altered plasma and RBC FA composition favoring inflammation. The use of prednisone was associated with differences in FA profile.  相似文献   
104.
105.
OBJECTIVES: To determine the role of nutritional parameters in influencing the risk of mortality in institutionalized elderly. DESIGN: A prospective cohort study in which subjects had several nutritional parameters measured at baseline and were followed for 19 months. Time to death and mortality were recorded starting immediately after enrollment. SETTING: Fourteen long-term care facilities (LTCFs). PARTICIPANTS: Four hundred eight elderly long-term care residents aged 60 and older who resided in the facility for more than 6 weeks. MEASUREMENTS: At baseline, knee height, weight, mid-arm circumference (MAC), skin-fold thickness, and fat-free mass using bioelectric impedance analysis were measured. Covariates included demographic factors, length of stay in the facility, functional status, and medical diagnoses. Cox proportional hazards regression analysis was used to identify independent predictors of mortality. Results are reported as mean+/-standard error of the mean (SEM). RESULTS: Overall, mortality rate was 28.4%. Univariate predictors included male sex, body mass index, MAC, and triceps skin fold. In multivariate analysis, male sex (hazard ratio (HR)=1.7, 95% confidence interval (CI)=1.2-2.7, P=.0096) and MAC less than 26 cm were significantly associated with increased risk of mortality (HR=4.8, 95% CI: 2.8-8.3, P<.0001). CONCLUSION: Among this elderly population living in LTCFs, MAC is the best nutritional predictor of mortality.  相似文献   
106.
Cement‐retained implant‐supported prostheses are widely used for restoring missing teeth; however, they show some complications in comparison to screw‐retained restorations, such as difficulty in retrieving the restoration and biocompatibility of cement. Therefore, the practitioner should consider several important aspects when using this type of restoration. In this regard, one major concern is appropriate cement selection, with considerations including cement biologic compatibility, methods for limiting the excess cement, ease of removing the excess cement, radiographic view of the cement, and also the possibility of future retrieval of the prosthesis. The aim of this review article was to address most aspects related to this type of prosthesis in terms of cementation.  相似文献   
107.

Introduction

The purpose of this study was to evaluate the role of working memory (WM) training on walking patterns in elderly people.

Methods

20 elderly adults were selected and assigned randomly to two groups: WM training group and control group. WM training group received 6 weeks of computerized training on various spatial and verbal WM tasks. The spatial-temporal parameters, the ground reaction force and the timing activity of muscles in pre-posttest and in a follow-up were taken.

Result

The results indicated that a significant change in gait speed, double support time and stride time (p < 0.05). Alternations in ground reaction force (GRF) components were found significant. Timing of muscle activity also showed non-significant change after WM intervention.

Conclusion

Based on the results of this study, it can be concluded that WM intervention can be applied to improve gait parameters. The improvements in vertical ground reaction force after training may result in an increase upright stability and a decreased in rate falls.  相似文献   
108.

Objects and design

Regarding to anti-inflammatory role of interleukin (IL) 10, its inhibitory effects on p38MAPK activity and, different pro and anti-inflammatory roles of activated p38MAPK in cells, this study was aimed to investigate relationship between serum IL10 level and p38MAPK enzyme activity on behavioral and cellular aspects variation of hyperalgesia during different stages of arthritis in rats.

Materials and methods

Adjuvant arthritis (AA) was induced by a single subcutaneous injection of complete Freund’s adjuvant into the rats’ hind paw. Behavioral and inflammatory responses were assessed at 0, 3, 7, 14, and 21 days of study. Receptor and other protein enzyme expression variations were detected by western blotting. Anti-IL10 and p38MAPK inhibitor were administered daily during the 21 days of study.

Result

Daily treatment with anti-IL10 antibody significantly increased paw edema and hyperalgesia in the AA group compared with the AA control group. Administration of anti-IL10 antibody caused significant increase in the ratio of phosphorylated p38 to p38MAPK enzyme level expression on 14th and 21st days of study compared with the AA control group.

Conclusion

Our study confirmed that a part of anti- inflammatory effects of serum IL10 during AA inflammation was mediated via inhibition of p38MAPK enzyme phosphorylation. Moreover, these findings suggest that increase in the level of spinal mu opioid receptor expression during AA inflammation is not mediated via the direct effect of serum IL10 on spinal p38MAPK.  相似文献   
109.
Single-ventricle anomaly is a hereditary heart disease that is characterized by anatomical malformations. The main consequence of this malformation is desaturated blood flow, which without proper treatment increases the risk of death. The classical treatment is based on a three-stage palliative procedure which should begin from the first few days of patient’s life. The final stage is known as Fontan procedure, in which inferior vena cava is directly connected to pulmonary arteries without going through the ventricle. This connection is called total cavopulmonary connection (TCPC). After surgery, the single ventricle supplies adequate and saturated systemic blood flow to the body; however, TCPC contains low pressure and low flow pulsatility. To overcome this problem, a new method is proposed wherein pulsatile blood will be directed to the TCPC through the stenosed main pulmonary artery. In this study, through the use of Computational Fluid Dynamics, T-shaped (MRI-based) and Y-shaped (computer-generated) geometries are compared in order to determine the influence of this modification on pulsation of blood flow as well as energy loss in pulmonary arteries. The results indicate that energy loss in Y-shaped geometry is far less than T-shaped geometry, while the difference in flow pulsatility is insignificant.  相似文献   
110.
Abstract

Aims: Extremely low-frequency electromagnetic fields (ELF-EMF) can affect biological systems and alter some cell functions like proliferation rate. Dental pulp tissue is known as a source of multipotent stromal stem cells (MSCs), which can be obtained by a less invasive and more available process compared to bone marrow-derived stem cells (BMSCs). This study aimed to consider the effect of ELF-EMF on proliferation rates of human dental pulp stem cells (hDPSCs).

Material and methods: ELF-EMF was generated by a system including autotransformer, multi-meter, solenoid coils, teslameter and its probe. The effect of ELF-EMF with the intensity of 0.5 and 1?mT and 50?Hz on the proliferation rate of hDPSCs was assessed in 20 and 40?min per day for 7?days. MTT assay and DAPI test were used to determine the growth and proliferation of DPSCs.

Results: Based on MTT, ELF-EMF has maximum effect with the intensity of 1?mT for 20?min/day on the proliferation of hDPSCs. The survival and proliferation rate in all exposure groups were significantly higher than the control group. Based on the data obtained from MTT and DAPI assay, the number of viable cells in the group exposed to 1?mT for 20?min/day was higher than other groups (p?<?.05).

Conclusions: Regarding to the results of this study, 0.5 and 1?mT ELF-EMF can enhance survival and proliferation rates of hDPSCs.  相似文献   
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