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61.
Our previous studies indicated that native carbonic anhydrase does not interact with hydrophobic adsorbents and that it acquires this ability upon denaturation. In the present study, an apo form of the enzyme was prepared by removal of zinc and a comparative study was performed on some characteristic features of the apo and native forms by far- and near-UV circular dichroism (CD), intrinsic fluorescent spectroscopy, 1-anilino naphthalene-8-sulfonate (ANS) binding, fluorescence quenching by acrylamide, and Tm measurement. Results indicate that protein flexibility is enhanced and the hydrophobic sites become more exposed upon conversion to the apo form. Accordingly, the apo structure showed a greater affinity for interaction with hydrophobic adsorbents as compared with the native structure. As observed for the native enzyme, heat denaturation of the apo form promoted interaction with alkyl residues present on the adsorbents and, by cooling followed by addition of zinc, catalytically-active immobilized preparations were obtained.  相似文献   
62.
Most of the modulating effects of cannabinoids on pain are through putative cannabinoid CB1 and CB2 receptors. However, the involvement of other receptors is also suggested. Cannabinoid compounds with analgesic activity such as palmitoylethanolamide (PEA) show low affinity to CB1 and CB2 receptors, yet selectively activate GPR55 receptors. The objective of the present study was to evaluate the possible role of spinal CB1 and GPR55 receptors on antinociceptive activity of PEA in formalin test as well as in the spinal expression of IL1-β in rat. Intrathecal (i.t.) administration of PEA (1, 10 μg) significantly decreased both pain-related scores in formalin test and IL1-β expression in rat spinal cord. Pretreatment of rats with low doses of CB1 receptor antagonist/GPR55 receptor agonist AM251 (10, 100 ng; i.t.), did not attenuated the effect of PEA, yet even significantly increased the effect of PEA on IL1-β expression in rat spinal cord. Interestingly, i.t. administration of low doses of AM251 per se significantly decreased both pain related behavior and spinal IL1-β expression in formalin test. These findings suggest the possible involvement of receptors other than CB1 receptors in spinal pain pathways, such as GPR55, in pain modulating activity of cannabinoids.  相似文献   
63.
Caspase-8 (CASP8) plays a critical role in regulating apoptosis, and its functional polymorphisms may modify cancer risk. We investigated the possible association between CASP8 -652 6N ins/del (rs3834129) and the risk of breast cancer in a sample of Iranian population. This case-control study was done on 236 breast cancer patients and 203 cancer free healthy female. We designed a rapid and simple bi-directional PCR allele-specific amplification (bi-PASA) for detection of CASP8 -652 6N ins/del polymorphism. The results showed that the CASP8 -652 6N del/dl genotype was inversely associated with breast cancer risk (OR=0.33, 95% CI=0.17-0.65, p=0.001). The frequencies of the del allele in cases and controls were 29.1% and 38.6%, respectively. An inverse association between CASP8 6N del variant and the risk of breast cancer (OR=0.66, 95% CI=0.66-0.87, p=0.002) was found. In conclusion, the result suggests that the CASP8 -652 6N del polymorphism plays a protective role in susceptibility to breast cancer in our population. Further studies in other populations with larger samples are needed to confirm these findings.  相似文献   
64.
65.
The circulating population of peripheral T lymphocytes obtained from a blood sample can provide a large amount of information about an individual's medical status and history. Recent evidence indicates that the detection and functional characterization of antigen-specific T cell subsets within the circulating population may provide a diagnostic indicator of disease and has the potential to predict an individual's response to therapy. In this report, a microarray detection platform that combines grating-coupled surface plasmon resonance imaging (GCSPRI) and grating-coupled surface plasmon coupled emission (SPCE) fluorescence detection modalities were used to detect and characterize CD4(+) T cells. The microspot regions of interest (ROIs) printed on the array consisted of immobilized antibodies or peptide loaded MHC monomers (p/MHC) as T cell capture ligands mixed with additional antibodies as cytokine capture ligands covalently bound to the surface of a corrugated gold sensor chip. Using optimized parameters, an unlabeled influenza peptide reactive T cell clone could be detected at a frequency of 0.1% in a mixed T cell sample using GCSPRI. Additionally, after cell binding was quantified, differential TH1 cytokine secretion patterns from a T cell clone cultured under TH1 or TH2 inducing conditions was detected using an SPCE fluorescence based assay. Differences in the secretion patterns of 3 cytokines, characteristic of the inducing conditions, indicated that differences were a consequence of the functional status of the captured cells. A dual mode GCSPRI/SPCE assay can provide a rapid, high content T cell screening/characterization tool that is useful for diagnosing disease, evaluating vaccination efficacy, or assessing responses to immunotherapeutics.  相似文献   
66.
In Vitro Insulin Release from Thermosensitive Chitosan Hydrogel   总被引:1,自引:0,他引:1  
Recently, great attention has been paid to in situ gel-forming chitosan/glycerol-phosphate (chitosan/Gp) solution due to their good biodegradability and thermosensitivity. This in situ gel-forming system is injectable fluid that can be introduced into the body in a minimally invasive manner prior to solidifying within the desired tissue. At the present study, insulin release from chitosan/Gp solution has been investigated. Insulin in different concentrations was loaded in two formulations of chitosan/Gp solution and in vitro drug release was studied over a period of 3 weeks. Results indicated that the release of insulin from chitosan/Gp gel decreases by increasing in Gp salt and initial insulin concentration. Stability of released insulin was investigated by 8-anilino-1-naphthalenesulfonate probe. Results proved that insulin have been released in its native form. Because of simple preparation and administration, prolonged release of insulin and stability of released insulin, this in situ gel-forming system could be used as a controlled release delivery system for insulin.KEY WORDS: biodegradable, chitosan, controlled release, in situ forming, insulin  相似文献   
67.
Ghrelin, the endogenous ligand for growth hormone secretagogue receptor, has been reported to prevent ischemia/reperfusion (I/R) injury in various tissues by its antioxidant activity. Therefore, this study was aimed to investigate the effect of ghrelin on sperm quality and antioxidant enzyme activity in a rat testicular ischemia/reperfusion injury model. Forty-two male Wistar rats were divided into groups control, I/R, and I/R plus ghrelin. The right testes were rotated 720° for 1 h and were allowed to reperfuse for 4 h and 30 days thereafter. Ghrelin (40 nmol/kg IP) or vehicle (physiological saline) was administrated 15 min before reperfusion. After 4 h of reperfusion, a right orchiectomy was performed to measure the biochemical parameters. In addition, the sperm was collected from the epididymis after 30 days of reperfusion, and sperm characteristics were examined. The malondialdehyde levels of the testis tissues were significantly increased, but a statistically significant decrease was found in the superoxide dismutase, glutathione peroxidase, and catalase activities in the I/R group as compared with the control, indicating I/R injury. The sperm evaluation showed a significant reduction in all characteristics resulted from I/R compared with the control. In the ghrelin-treated group, the malondialdehyde values were significantly lowered, and only enzyme activity of glutathione peroxidase showed significant increases compared with the I/R group. Ghrelin significantly enhanced sperm motility, movement, and concentration but did not prevent I/R-induced reduction in membrane integrity in the testes of rats compared to the I/R group. Our results suggest that ghrelin treatment has a protective role on IR-induced testicular injury, and this effect may be due to its antioxidant properties.  相似文献   
68.

Background

Asthma-related health resource use and costs may be influenced by increasing asthma prevalence, changes to asthma management guidelines, and new medications over the last decade. The objective of this work was to analyze direct asthma-related medical costs, and trends in total and per-patient costs of hospitalizations, physician visits, and medications.

Methods

A cohort of asthma patients from British Columbia (BC), Canada, was created. Asthma patients were identified using a validated case definition. Costs for hospitalizations, physician visits, and medications were calculated from billing records (in 2008 Canadian dollars). Trends in total and per-patient costs over the study period were analyzed using Generalized Linear Models.

Results

398,235 patients satisfied the asthma case definition (mid-point prevalence 8.0%). Patients consumed $315.9 million (M) in direct asthma-related health resources between 2002 and 2007. Hospitalizations, physician visits, and medication costs accounted for 16.0%, 15.7% and 68.2% of total costs, respectively. Cost of asthma increased from $49.4 M in 2002 to $54.7 M in 2007. Total annual costs attributable to hospitalizations and physician visits decreased (−39.8% and −25.5%, respectively; p<0.001), while medication costs increased (+38.7%; p<0.001).

Interpretation

This population-based analysis shows that the total direct cost of asthma in BC has increased since 2002, mainly due to a rise in asthma prevalence and cost of medication. Combination therapy with inhaled corticosteroids/long-acting beta-agonists has become a significant component of the cost of asthma. Although billing records capture only a fraction of the true burden of asthma, the simultaneous increase in medication costs and reductions in hospitalization and physician visit costs provides valuable insight for policy makers into the shifts in asthma-related resource use.  相似文献   
69.
ABSTRACT: BACKGROUND: The lavender phenotype in quail is a dilution of both eumelanin and phaeomelanin in feathers that produces a blue-grey colour on a wild-type feather pattern background. It has been previously demonstrated by intergeneric hybridization that the lavender mutation in quail is homologous to the same phenotype in chicken, which is caused by a single base-pair change in exon 1 of MLPH. RESULTS: In this study, we have shown that a mutation of MLPH is also associated with feather colour dilution in quail, but that the mutational event is extremely different. In this species, the lavender phenotype is associated with a non-lethal complex mutation involving three consecutive overlapping chromosomal changes (two inversions and one deletion) that have consequences on the genomic organization of four genes (MLPH and the neighbouring PRLH, RAB17 and LRRFIP1). The deletion of PRLH has no effect on the level of circulating prolactin. Lavender birds have lighter body weight, lower body temperature and increased feed consumption and residual feed intake than wild-type plumage quail, indicating that this complex mutation is affecting the metabolism and the regulation of homeothermy. CONCLUSIONS: An extensive overlapping chromosome rearrangement was associated with a non-pathological Mendelian trait and minor, non deleterious effects in the lavender Japanese quail which is a natural knockout for PRLH.  相似文献   
70.

Background

The population of Japan has achieved the longest life expectancy in the world. To further improve population health, consistent and comparative evidence on mortality attributable to preventable risk factors is necessary for setting priorities for health policies and programs. Although several past studies have quantified the impact of individual risk factors in Japan, to our knowledge no study has assessed and compared the effects of multiple modifiable risk factors for non-communicable diseases and injuries using a standard framework. We estimated the effects of 16 risk factors on cause-specific deaths and life expectancy in Japan.

Methods and Findings

We obtained data on risk factor exposures from the National Health and Nutrition Survey and epidemiological studies, data on the number of cause-specific deaths from vital records adjusted for ill-defined codes, and data on relative risks from epidemiological studies and meta-analyses. We applied a comparative risk assessment framework to estimate effects of excess risks on deaths and life expectancy at age 40 y. In 2007, tobacco smoking and high blood pressure accounted for 129,000 deaths (95% CI: 115,000–154,000) and 104,000 deaths (95% CI: 86,000–119,000), respectively, followed by physical inactivity (52,000 deaths, 95% CI: 47,000–58,000), high blood glucose (34,000 deaths, 95% CI: 26,000–43,000), high dietary salt intake (34,000 deaths, 95% CI: 27,000–39,000), and alcohol use (31,000 deaths, 95% CI: 28,000–35,000). In recent decades, cancer mortality attributable to tobacco smoking has increased in the elderly, while stroke mortality attributable to high blood pressure has declined. Life expectancy at age 40 y in 2007 would have been extended by 1.4 y for both sexes (men, 95% CI: 1.3–1.6; women, 95% CI: 1.2–1.7) if exposures to multiple cardiovascular risk factors had been reduced to their optimal levels as determined by a theoretical-minimum-risk exposure distribution.

Conclusions

Tobacco smoking and high blood pressure are the two major risk factors for adult mortality from non-communicable diseases and injuries in Japan. There is a large potential population health gain if multiple risk factors are jointly controlled. Please see later in the article for the Editors'' Summary  相似文献   
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