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41.
Heat shock proteins (HSPs) have been repeatedly implicated in the pathogenesis of rheumatoid arthritis (RA). The authors aimed to study applicability of heat shock protein 70 (HSPA1A) serum levels as a diagnostic factor and a severity indicator in patients with RA and to quantify cut-off point that predicts status of RA with highest specificity. A total of 76 patients with RA and 36 healthy adults were studied in this case-control analysis. Patients had a higher HSPA1A level than the control group (0.78 ± 0.13 vs. 0.12 ± 0.02 ng/mL, p = 0.006), irrespective of presence of absence of rheumatoid factor or anti-citrullinated cyclic peptide. Next, diagnostic accuracy of the HSPA1A in diagnosis of RA was evaluated (area under curve 0.71; p < 0.05). HSPA1A predicted status of having RA in levels above 0.42 ng/mL with more than 90 % specificity. In addition to diagnostic value, HSPA1A can distinguish between high disease activity (1.66 ± 0.75 ng/mL) and low (0.49 ± 0.1 ng/mL), moderate (0.52 ± 0.12 ng/mL), or remission phase (0.48 ± 0.11 ng/mL). Moreover, patients in remission still had a higher HSPA1A level compared to normal subject (0.48 ± 0.11 vs. 0.12 ± 0.02 ng/mL, p < 0.05). Our results showed that serum HSPA1A could be implemented as a specific tool to facilitate diagnosis and monitoring disease activity in patients with rheumatoid arthritis.

Electronic supplementary material

The online version of this article (doi:10.1007/s12192-015-0578-z) contains supplementary material, which is available to authorized users.  相似文献   
42.
A series of novel 2-(3,5-diphenyl-4,5-dihydro-1H-pyrazol-1-yl)-4-phenylthiazoles have been prepared by a three-component cyclo-condensation of various chalcones, thiosemicarbazide and phenacyl bromide. The easy work-up of the products, rapid reaction, and mild conditions are notable features of this protocol. The reaction was efficiently catalyzed in one-pot by a few drops of HCl in EtOH under reflux conditions providing the title compounds in moderate to high yields. The antibacterial activity of the selected products was examined. Some products exhibit promising activities.  相似文献   
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A simple bio-conjugation procedure to surround a single horseradish peroxidase (HRP) enzyme molecule with dendritic polyester macromolecules (polyester-32-hydroxyl-1-carboxyl bis-MPA dendron, generation 5) was proposed. The characterization of resultant nanoparticles entitled HRP dendrozyme, was performed by transmission electron microscopy, dynamic light scattering, gel permeation chromatography and Fourier transform infrared spectroscopy. The results showed that HRP nanoparticles were spherical in shape and have an average size of 14 ± 2 nm in diameter. Furthermore, bio-conformational characterization of HRP dendrozyme was performed by means of circular dichroism and fluorescence spectroscopy to evaluate the secondary and tertiary structure changes after enzyme modification. These investigations revealed that protein conformation had small changes (in secondary and tertiary structures) after bio-conjugation. We also reported here that dendritic modification did not significantly affect the kinetic parameters of free HRP. The stabilization of HRP with dendron macromolecules as single enzyme nanoparticles resulted in improvement of half-life over 70 days storage at 4 °C as well as its tolerance under different elevated temperatures up to 80 °C and in the presence of organic solvents for 15 min. These significant results promise extensive applications of HRP particularly in harsh environmental conditions.  相似文献   
45.
A new dibenzothiophene (DBT) desulfurizing bacterium was isolated from oil-contaminated soils in Iran. HPLC analysis and PCR-based detection of the presence of the DBT desulfurization genes (dszA, dszB and dszC) indicate that this strain converts DBT to 2-hydroxybiphenyl (2-HBP) via the 4S pathway. The strain, identified as Rhodococcus erythropolis SHT87, can utilize DBT, dibenzothiophene sulfone, thiophene, 2-methylthiophene and dimethylsulfoxide as a sole sulfur source for growth at 30 °C.The maximum specific desulfurization activity of strain SHT87 resting cells in aqueous and biphasic organic–aqueous systems at 30 °C was determined to be 0.36 and 0.47 μmol 2-HBP min−1 (g dry cell)−1, respectively. Three mM DBT was completely metabolized by SHT87 resting cells in the aqueous and biphasic systems within 10 h. The rate and the extent of the desulfurization reaction by strain SHT87 suggest that this strain can be used for the biodesulfurization of diesel oils.  相似文献   
46.
A frozen section method utilising chicken intestinal tissue was developed to study the Eimeria tenella attachment ex vivo. In order to examine Eimeria-epithelial cell attachment, 105E. tenella sporozoites were incubated with each caecal frozen section (6, 10 and 14 μm) for 1 h in 5% CO2 incubator at 41 °C. E. tenella sporozoites attached successfully to enterocytes in 14 μm thick of caecal sections. Sporozoite attachment to caecal sections was shown to be dependent on the number of parasites added. To evaluate the method, E. tenella sporozoites were incubated to its preferred (caecum) and non-preferred (duodenum and jejunum) intestinal sites. The number of sporozoites attached to the caecal enterocytes was significantly greater (P < 0.0001) in comparison with the limited number of sporozoites attached to enterocytes of non-preferred intestinal sites. This method was shown to be able to reveal differences in binding capability and allows for comparison of intestinal site attachment.  相似文献   
47.

Aim

Evaluation of application of EPID for rapid QC testing of linear accelerator.

Background

Quality control of a linear accelerator device is a time and energy intensive process. In this study, attempts have been made to perform the linear accelerator quality control using electronic portal imaging device (EPID), which is mounted on most accelerators.

Materials and methods

First, quality control and dosimetry parameters of the device were determined and measured based on standard protocols to ensure full calibration of the accelerator. Then, various features of EPID including spatial resolution and contrast resolution, the effect of buildup region, dose response and image uniformity were evaluated. In the next step, consistent with the parameters of linear accelerator quality control including field size, field flatness and symmetry, the light field coincidence with X-ray field, mechanical stability and multileaf collimator position accuracy test, the output images of device were obtained.After feeding images to the MATLAB software, their pixel content was analyzed. All measurements of the three photon beams were repeated three times.

Results

The EPID image had a desirable resolution, contrast and uniformity and displayed high sensitivity to dose changes with linear dose response. Seven qualitative parameters of the linear accelerator were then controlled by EPID.

Conclusions

The results of the linear accelerator quality control using the EPID were consistent with practice. Quality control using the EPID was more convenient and faster than conventional methods.  相似文献   
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Several studies suggest that the response to various stressors differs between the sexes. We aimed to study serum HSP70 and levels of oxidized-LDL (ox-LDL) as markers of oxidative stress in men and women with type 2 diabetes. We quantified serum HSP70 and levels of ox-LDL in three cohorts; patients with newly diagnosed diabetes, patients with long-standing diabetes and normal controls. The cohort of patients with newly diagnosed diabetes was followed up for 3 months under glucose-lowering therapy with metformin. Our findings showed that serum HSP70 level was increased in women with long-standing diabetes in comparison with men. HSP70 did not decrease after glucose lowering therapy in women with newly diagnosed diabetes, but it did decrease in men. There was no significant difference on ox-LDL between men and women in any of the studied cohorts. It decreased significantly in the cohort of patients with newly diagnosed diabetes after treatment, regardless of sex. There was no significant correlation between HSP70 and ox-LDL in any of the studied cohorts except among normal women. We suggest that diabetes induces an immune response and impairs cellular defense mechanisms against oxidative stress more commonly in women with type 2 diabetes than in men.  相似文献   
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