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101.
The objective of this randomized, double-blind placebo-controlled clinical trial was to evaluate the value of allopurinol treatment on reduction of oxidative stress in patients with diabetes type II patients. Forty-one diabetic type II subjects were randomly assigned to two groups. One group (n = 20) received 100 mg allopurinol three times a day for 14 days and the other group (n = 21) received a placebo. Blood and saliva samples were collected before and after intervention for analysis of lipid peroxidation level and total antioxidant power as indices of oxidative stress. At the beginning of the study, the groups were similar based upon age, duration of diabetes, fasting glucose, and HbA1c. Both allopurinol and placebo were effective in reduction of lipid peroxidation and total antioxidant power whether in saliva or plasma in a similar extent. HbA1c and FBS levels did not change through the study neither in case or placebo group. It is concluded that allopurinol therapy is not more effective than placebo in reduction of oxidative stress in diabetic patients. The same trend of changes in blood and saliva shown for oxidative stress indices was interesting and suggests a chance for saliva to be valuable in diagnosis of oxidative stress. However, to elaborate the exact role of allopurinol in diabetes, further large randomized clinical trials are needed.  相似文献   
102.
BACKGROUND AND PURPOSE:Dual-energy CT is not used routinely for evaluation of the head and neck, and there is no consensus on the optimal virtual monochromatic image energies for evaluating normal tissues or head and neck cancer. We performed a quantitative evaluation to determine the optimal virtual monochromatic images for visualization of normal tissues, head and neck squamous cell carcinoma, and lymphadenopathy.MATERIALS AND METHODS:Dual-energy CT scans from 10 healthy patients and 30 patients with squamous cell carcinoma were evaluated at different virtual monochromatic energy levels ranging from 40 to 140 keV. The signal-to-noise ratios of muscles at 6 different levels, glands (parotid, sublingual, submandibular, and thyroid), 30 tumors, and 17 metastatic lymph nodes were determined as measures of optimal image quality. Lesion attenuation and contrast-to-noise ratios (compared with those of muscle) were evaluated to assess lesion conspicuity.RESULTS:The optimal signal-to-noise ratio for all the tissues was at 65 keV (P < .0001). However, tumor attenuation (P < .0001), attenuation difference between tumor and muscles (P = .03), and lesion contrast-to-noise ratios (P < .0001) were highest at 40 keV.CONCLUSIONS:The optimal image signal-to-noise ratio is at 65 keV, but tumor conspicuity compared with that of muscle is greatest at 40 keV. Optimal evaluation of the neck may be best achieved by a multiparametric approach, with 65-keV virtual monochromatic images providing the best overall image quality and targeted use of 40-keV virtual monochromatic images for tumor evaluation.

There are emerging applications of dual-energy CT (DECT)1 in all the major subspecialties of radiology.28 Studies have increasingly been demonstrating potential advantages of DECT for the evaluation of head and neck pathologies.818 Extrapolating from abdominal imaging, 70-keV virtual monochromatic image (VMI) reconstructions are believed to be those that most closely resemble a standard single-energy CT acquisition19 and are usually the default setting for CT of the neck. On the other hand, enhancing tumors have increased attenuation on lower–kiloelectron volt (keV) VMIs, closer to the k edge of iodine,20 albeit at the expense of other factors such as increased image noise. A recent study using a dual-source system (Somatom Definition Flash; Siemens, Erlangen, Germany) evaluated extrapolated monoenergetic datasets at 40, 60, 80, and 100 keV, and the authors concluded that image reconstructions at 60 keV improved lesion enhancement and the contrast-to-noise ratio (CNR), subjective overall image quality, and tumor delineation in head and neck squamous cell carcinoma (HNSCC).10Most studies that evaluated HNSCC, other than a study that evaluated DECT for the differentiation of benign and malignant tumors,14 were performed by using dual-source CT. The other major system currently in clinical use is a single-source single-detector DECT system. This system is based on rapid kilovoltage peak (kVp) switching that enables near-simultaneous acquisition of high- and low-energy projection data (GE Discovery CT750HD; GE Healthcare, Milwaukee, Wisconsin). In this system, spectral separation is achieved on the basis of projection-based material decomposition by using the fast sampling capabilities of a proprietary scintillator detector with low afterglow.5,21 Although the broad principles behind both DECT acquisition systems are similar, there are significant differences in hardware, acquisition, and postprocessing. As a result, any cross-platform application of observations made by using either system requires validation. Furthermore, there is currently no consensus on the optimal VMIs for the evaluation of HNSCC or the approach to incorporate DECT into routine clinical use.The hypothesis behind our investigation was that VMIs acquired at energies other than 70 keV, either alone or in combination, can enhance the conspicuity of HNSCC. The objective of this investigation, therefore, was to determine the optimal VMI that provides the highest image quality and the VMI that enables optimal tumor visualization by using a single-source DECT scan with rapid kVp switching. This determination was made by objectively and quantitatively analyzing normal structures at different levels in the neck and tumors at different primary sites. Spectral evaluation was performed by using different VMI energy levels ranging from 40 to 140 keV in 5-keV increments, and mean attenuation, SNR, and CNR were used as end points for evaluation.  相似文献   
103.

Context

Omega-3 fatty acids have been recently proposed to induce neural improvement in patients with spinal cord injury (SCI) while affecting some hormones including leptin and adiponectin.

Objectives

We tried to evaluate the effect of omega-3 fatty acids on circulatory concentrations of leptin and adiponectin among these patients.

Design

This study is a double-blinded randomized clinical trial with intervention duration of 14 months.

Setting

A tertiary rehabilitation center.

Participants

Total of 104 patients with SCI who did not meet our exclusion criteria entered the study. Those with history of diabetes, cancer, endocrinology disease, acute infection, and use of special medications were excluded. Patients were divided randomly into the treatment and control group by using permuted balanced block randomization.

Intervention

The treatment group received two MorDHA® capsules per day (each capsule contain 465 mg of docosahexaenoic acid (DHA) and 63 mg of eicosapentaenoic acid (EPA)) for 14 months while the control group received placebo capsules with similar color, shape, and taste.

Main outcomes measures

Leptin and adiponectin concentrations in plasma were measured at the beginning of trial and then after 6 and 14 months.

Results

Fourteen months of treatment with DHA and EPA did not influence concentrations of leptin but adiponectin level was significantly decreased (P: 0.03). Weight was positively correlated with leptin level at stage 0 of trial (P: 0.008, r = 0.41) while this association was attenuated through stages of trial after intervention.

Conclusion

Our data show that omega-3 fatty acids may not affect plasma concentrations of leptin but adiponectin level is decreased in patients with SCI. Moreover, this intervention influences the linear relationship between weight and leptin after 14 months administration of DHA and EPA.  相似文献   
104.

Background

Clinical use of selective PDE3 inhibitors as cardiotonic agents is limited because of their chronotropic and lipolytic side effects. In our previous work, we synthesized a new PDE3 inhibitor named MC2 (6-[4-(4-methylpiperidin-1-yl)-4-oxobutoxy]-4-methylquinolin-2(1H)-one) which produced a high positive inotropic action with a negative chronotropic effect. This work was done to evaluate the effects of MC2 on adipocytes and compare its effects with those of amrinone and cilostamide.

Methods

Preadipocytes were isolated from rat adipose tissue and differentiated to adipocyte in the presence of cilostamide, amrinone or MC2. Lipolysis and adipogenesis was evaluated by measuring glycerol level and Oil Red O staining, respectively. Adipocyte proliferation and apoptosis were determined with MTT assay and Annexin V/PI staining, respectively.

Results

Differentiation to adipocyte was induced by amrinone but not by cilostamide or MC2. Basal and isoproterenol-stimulated lipolysis significantly increased by cilostamide (p < 0.05). Similarly, amrinone enhanced the stimulated lipolysis (p < 0.01). On the other hand, MC2 significantly decreased both adipogenesis (p < 0.05) and stimulated lipolysis (p < 0.001). Also, incubation of differentiated adipocytes with MC2 caused the loss of cell viability, which was associated with the elevation in apoptotic rate (p < 0.05).

Conclusion

Our data indicate that selective PDE3 inhibitors produce differential effects on adipogenesis and lipolysis. MC2 has proapoptotic and antilipolytic effects on adipocytes and does not stimulate adipogenesis. Therefore, in comparison with the clinically available selective PDE3 inhibitors, MC2 has lowest metabolic side effects and might be a good candidate for treatment of congestive heart failure.  相似文献   
105.
AIM: To compare higher order aberrations in two aspherical intraocular lenses (IOLs):Akreos advanced optics (AO) and Dr. Schmidt Microcrystalline 6125 aspheric anterior surface (MC6125AS) with each other.METHODS: Forty eyes of 39 patients underwent phacoemulsification and Akreos AO and MC6125AS were implanted in their eyes in a random manner. Three months post-operatively, higher order aberrations including spherical aberration, coma aberration, and total aberrations were measured and compared.RESULTS: The total aberration was 0.24±0.17 in eyes with Dr. Schmidt and 0.20±0.01 in eyes with Akreos AO (P=0.361). The mean of coma aberration was 0.17±0.21 and 0.09±0.86 in Dr. Schmidt and Akreos lenses, respectively (P=0.825). Total spherical aberration was almost the same in both groups (Mean:0.05, P=0.933). Best corrected visual acuity in Akreos AO (0.10±0.68) and Dr. Schmidt (0.09±0.67) did not differ significantly (P=0.700).CONCLUSION: There is no statistically significant difference in the higher order aberrations between these two aspherical lenses.  相似文献   
106.
Biomass conversion to carbonaceous materials and their use in various applications, such as capacitors, catalyst supports, and adsorbents, have attracted considerable attention from the viewpoint of green chemistry. In this regard, chicken egg white is one of the most important biomass, which can act as an in situ nitrogen doping source. In this paper, nitrogen-rich porous carbon material was synthesized from egg white biomass via pyrolysis at 600 °C under nitrogen atmosphere, followed by chemical activation with KOH at 500 °C. The results showed that the as-synthesized porous carbon material has a high content of nitrogen and high surface area, on which nitrogen can tune the surface hydrophobicity–hydrophilicity through interaction with water molecules. Then, the copper nanoparticles were immobilized on the surface of nitrogen-rich activated carbon by a chemical reduction method. Nanocatalyst structure was characterized by elemental analysis, TEM, AFM, Raman, FT-IR, porosimetry and atomic adsorption techniques. Finally, catalytic activity was evaluated for the one-pot synthesis of triazole in aqueous medium. The nanocatalyst offers some advantages such as excellent activity, low loading of catalyst, good yields of products and short reaction times.

Nitrogen-rich porous carbon (NAC) material was synthesized from egg white biomass via pyrolysis, followed by chemical activation with KOH. Then, the copper nanoparticles were immobilized on the surface of the NAC by chemical reduction method.  相似文献   
107.
ZnO/TiO2 anchored on a reduced graphene oxide (rGO) ternary nanocomposite heterojunction was synthesized via the multi-step method including hydrothermal, solvothermal and sol–gel methods. XRD, Raman, FESEM, EDX, Dot Mapping EDS, BET, FTIR, UV-VIS, TGA, and EIS techniques were utilized for characterizing as-synthesized catalysts. The XRD and Raman data proved the formation of anatase phase TiO2 and wurtzite phase ZnO in the prepared samples. Further, the UV-Vis spectrum confirmed that the band gap value of ZnO/TiO2 diminished on introduction of graphene oxide. Photocatalytic performance of the fabricated catalysts was investigated by decontamination of phenol in aqueous solutions. The effect of different operational factors such as pH, catalyst dosage, phenol concentration, and light illumination was investigated to find the optimum decontamination conditions. According to the results, complete degradation of phenol was achieved at pH = 4, catalyst dosage of 0.6 g L−1, light intensity of 150 W, and phenol initial concentration of 60 ppm at 160 min under visible light illumination. With the addition of graphene oxide to the composite, a significant increase was detected in the photocatalytic performance due to the higher available surface area and lower electron/hole recombination rate. In addition, the scavenging experiments revealed that the ·OH is responsible for the degradation of phenol during the reaction. The degradation mechanism, economic performance, mineralization, and recyclability were also investigated. Kinetic studies confirmed that photocatalytic degradation process followed the pseudo-first-order kinetic model. A case of real wastewater treatment was used to examine the performance of the catalyst for real case studies.

ZnO/TiO2 anchored on a reduced graphene oxide (rGO) ternary nanocomposite heterojunction was synthesized via the multi-step method including hydrothermal, solvothermal and sol–gel methods.  相似文献   
108.
109.
Exposure to 3, 4-methylenedioxymethamphetamine (MDMA) leads to spatial memory impairment and hippocampal cell death. In the present study we have examined the protective effects of N-acetyl-L-cysteine (NAC) on MDMA-induced neurotoxicity. A total of 56 male Sprague Dawley rats (200–250 g) received twice daily intraperitoneal (IP) injections of 5, 10 or 20 mg/kg MDMA plus NAC (100 mg/kg). Rectal temperatures were recorded before and after daily treatment. We used a Morris water maze (MWM) to assess spatial learning and memory. At the end of the study rats’ brains were removed, cells were counted and the level of Bcl-2, Bax and caspase-3 expression in the hippocampi were measured. NAC pretreatment significantly reduced MDMA-induced hyperthermia. In the MWM, NAC significantly attenuated the MDMA-induced increase in distance traveled; however the observed increase in escape latency was not significant. The decrease in time spent in the target quadrant in MDMA animals was significantly attenuated (p?<?0.001, all groups). NAC protected against MDMA-induced cell death and the up -regulation of Bax and Caspase-3, in addition to the down-regulation of Bcl-2. This data suggested a possible benefit of NAC in the treatment of neurotoxicity among those who use MDMA.  相似文献   
110.
Prognosis studies are fast developing and very practical types of medical research. Sciatica is one of the common types of low back pain and identifying prognostic factors of the illness can help physicians and patients to choose best method of practice. The prognostic factors of sciatica are presented from the Canon of Avicenna, one of the most famous physicians in the history of medicine.  相似文献   
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