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71.
Immobilized cells of Enterobacter agglomerans, able to reduce azo dyes enzymatically, were used as a biocatalyst for the decolorization of synthetic medium containing the toxic azo dye methyl red (MR). This bacterial strain exhibits high ability to completely decolorize 100 mg/L of MR after only 6 h of incubation under aerobic conditions. Cells of E. agglomerans were immobilized in calcium alginate, polyacylamide, cooper beech, and vermiculite, and were used for the decolorization of MR from synthetic water by using a fluidized bed bioreactor. The highest specific decolorization rate was obtained when E. agglomerans was entrapped in calcium alginate beads and was of about 3.04 mg MR/g cell/h with a 50% conversion time (t1/2) of about 1.6 h. Moreover, immobilized cells in calcium alginate continuously decolorized MR even after seven repeated experiments without significant loss of activity, while polyacrylamide-, cooper beech-, and vermiculite-immobilized cells retained only 62, 15, and 13% of their original activity, respectively.  相似文献   
72.
Extracellular matrix (ECM) proteins, such as collagen and fibronectin, play vital roles in development and maintenance of hard tissue (bone or tooth) and are, consequently, thoroughly investigated for construction of biomimetic scaffolds in combination with calcium phosphate (CaP) material (the major component of hard tissue) for bone or dental tissue engineering. Realizing the natural affinity of ECM components toward inorganic constituents of hard tissue, we successfully constructed the nanohybrids of DNA/CaP particles with either collagen 1 or fibronectin, which finally possessed the capability of specific recognition of integrin receptor for being swiftly internalized across the plasma membrane, leading to remarkably high transgene expression in mammalian cells. This new approach with precise receptor-specific delivery as well as 10- to 50-fold enhanced efficiency level compared to the classical one, has immediate applications for basic research and large scale production of recombinant therapeutic proteins and looks promising for gene therapy.  相似文献   
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75.
Here, we have investigated the therapeutic potency of EW-7197, a transforming growth factor-β type I receptor kinase inhibitor, against postsurgical adhesion band formation. Our results showed that this pharmacological inhibitor prevented the frequency and the stability of adhesion bands in mice model. We have also shown that downregulation of proinflammatory cytokines, reduce submucosal edema, attenuation of proinflammatory cell infiltration, inhibition of oxidative stress, decrease in excessive collagen deposition, and suppression of profibrotic genes at the site of surgery are some of the mechanisms by which EW-7197 elicits its protective responses against adhesion band formation. These results clearly suggest that EW-7197 has novel therapeutic properties against postsurgical adhesion band formation with clinically translational potential of inhibiting key pathological responses of inflammation and fibrosis in postsurgery patients.  相似文献   
76.
Lady beetles are the most important predatory species among arthropods; thus, studying their population parameters gives a clear picture about their life span. The demography of the lady beetle, Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae), was studied under laboratory condition, on Aphis fabae at 27?°C based on the age-stage, two-sex life table. The means and standard errors were estimated by the bootstrap techniques. The results showed that the intrinsic rate of increase (r) and the finite rate of increase (λ) were 0.18 and 1.20 d?1, respectively. The net reproduction rate (R 0) and the gross reproduction rate were 232.49 and 442.48 offspring/individual, respectively. The mean generation time (T) was 29.03?days. The first peak of reproductive value in females was on the 18th day, which coincides with the total pre-oviposition period counted from birth. The life expectancy curve (exj ) of a new hatched female adult was 60?days. The results demonstrated that growth, survival and development of the predator can be described accurately by use of the age-stage, two-sex life table.  相似文献   
77.
Tissue and stem cell encapsulation andtransplantation were considered as promising tools in the treatment of patients with diabetes mellitus. The aim of this study was to evaluate the effect of microfluidic encapsulation on the differentiation of trabecular meshwork mesenchymal stem cells (TM-MSC), into insulin-producing cells (IPCs) both in vitro and in vivo. The presence of differentiated cells in microfibers (three dimensional [3D]) and tissue culture plates (TCPS; two dimensional [2D]) culture was evaluated by detecting mRNA and protein expression of pancreatic islet-specific markers as well as measuring insulin release of cells in response to glucose challenges. Finally, semi-differentiated cells in microfibers (3D) and 2D cultures were used to control the glucose level in diabetic rats. The results of this study showed that MSCs differentiated in alginate microfibers (fabricated by microfluidic device) express more Pdx-1 mRNA (1.938-fold, p-value: 0.0425) and Insulin mRNA (2.841-fold, p-value: 0.0001) compared with those cultured on TCPS. Furthermore, cell encapsulation in microfluidic derived microfibers decreased the level of blood glucose in diabetic rats. The approach used in this study showed the possibility of alginate microfibers as a matrix for differentiation of TM-MSCs (as a new source) into IPCs. In addition, it could minimize different steps in stem cell differentiation, handling, and encapsulation, which lead to loss of an unlimited number of cells.  相似文献   
78.
Central administration of exogenous cyclo(His-Pro) (CHP) is known to produce hypothermia in rodents. In the present study, we examined the role of endogenous CHP in cold-induced hypothermia in the desert rat, Mastomys natalensis. The results of these studies show that a rise in hypothalamic CHP content accompanied a decrease in rectal temperature during cold exposure. Immunoneutralization of endogenous CHP resulted in a significant decline in cold-induced hypothermia. In addition, central administration of cyclo(Ala-Gly), a structural analogue of CHP, also led to a decrease in cold-induced hypothermia. The results of these studies show that changes in endogenous CHP levels may affect body temperature regulation.  相似文献   
79.

Objectives

Health-related quality of life (HRQoL) is considered a very important outcome indicator in patients with Parkinson’s disease (PD). A broad list of motor and non-motor features have been shown to affect HRQoL in PD, however, there is a dearth of information about the complexity of interrelationships between determinants of HRQoL in different PD phenotypes. We aimed to find independent determinates and the best structural model for HRQoL, also to investigate the heterogeneity in HRQoL between PD patients with different phenotypes regarding onset-age, progression rate and dominant symptom.

Methods

A broad spectrum of demographic, motor and non-motor characteristics were collected in 157 idiopathic PD patients, namely comorbidity profile, nutritional status, UPDRS (total items), psychiatric symptoms (depression, anxiety), fatigue and psychosocial functioning through physical examination, validated questionnaires and scales. Structural equation model (SEM) and multivariate regressions were applied to find determinants of Parkinson’s disease summary index (PDSI) and different domains of HRQoL (PDQ-39).

Results

Female sex, anxiety, depression and UPDRS-part II scores were the significant independent determinants of PDSI. A structural model consisting of global motor, global non-motor and co-morbidity indicator as three main components was able to predict 89% of the variance in HRQoL. In older-onset and slow-progression phenotypes, the motor domain showed smaller contribution on HRQoL and the majority of its effects were mediated through non-motor features. Comorbidity component was a significant determinant of HRQoL only among older-onset and non-tremor-dominant PD patients. Fatigue was not a significant indicator of non-motor component to affect HRQoL in rapid-progression PD.

Conclusions

Our findings showed outstanding heterogeneities in the pattern and determinants of HRQoL among PD phenotypes. These factors should be considered during the assessments and developing personalized interventions to improve HRQOL in PD patients with different phenotypes or prominent feature.  相似文献   
80.
The aim of this study was to investigate the effect of a hypertrophic training program during Ramadan on levels of circulating antioxidants and oxidative stress biomarkers in trained bodybuilders. Eight male bodybuilders visited the laboratory two days before the start of Ramadan and on the 29th day of Ramadan (end-Ramadan), to undergo anthropometric measurement, to complete a dietary questionnaire, and to provide fasting blood and urine samples. Plasma thiobarbituric acid reactive substance and protein-bound carbonyl concentrations were measured in the plasma to indicate lipid and protein oxidation, respectively. These did not change significantly during Ramadan. Superoxide dismutase and glutathione peroxidase activities, indices of erythrocytes antioxidant status, increased by 24% (p = 0.011) and 12% (p = 0.01), respectively, from before to the end of Ramadan. However, erythrocyte catalase activity did not change significantly. Uric acid values increased by 17% (p < 0.001) from before to the end of Ramadan, but ferric-reducing ability and Vitamin E levels of the plasma remained unchanged. A significant correlation was found between uric acid values and urine specific gravity (r = 0.70; p < 0.05) only at the end of Ramadan. We conclude that continuing a hypertrophic training program during Ramadan fasting does not increase oxidative stress but does increase antioxidant status in bodybuilders.  相似文献   
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