The effect of 6 weeks decreased activity in the form of spinal cord ligation on CDK5 expression in sciatic nerve of Wistar male rats with neuropathic pain

چکیده مقدمه: درد نوروپاتیک به صورت درد ناشی از آسیب یا بیماری سیستم عصبی حسی- پیکری تعریف می‌شود. نورون‌ها به کاهش و افزایش فعالیت به لحاظ بیوشمیایی سازگار می‌شوند که چنین تغییرات بیوشمیایی می‌تواند در حفظ و بقای نورون‌ها اثر گذار باشد، با توجه به نقش تنظیمی CDK5 در عملکرد و ساختار اعصاب هدف از انجام پژوهش حاضر بررسی تاثیر شش هفته فعالیت کاهش یافته به شکل درد نوروپاتیک بر بیان CDK5 در عصب سیاتیک رت های نر دارای درد نوروپاتیک بود. مواد و روش‌ها: 10سر موش صحرایی نر نژاد ویستار با میانگین وزن 20±250 گرم به 2 گروه کنترل سالم(5n=) و گروه فعالیت کاهش یافته (SNL) (5n=) تقسیم شدند. طی شش هفته آینده آزمون‌های رفتاری درد نوروپاتیک در گروه‌های پژوهشی به طور مستمر انجام شد. در پایان 6 هفته تغییرات بیان ژن CDK5 در عصب سیاتیک با تکنیک Real time اندازه‌گیری و با روش 2-ΔΔCT محاسبه شد. نتایج: پس از 6 هفته وزن عضله نعلی در گروه لیگاتوربندی شده به طور معناداری نسبت به گروه کنترل کاهش داشت(05/0 ≤ P). در آزمون‌های رفتاری درد نوروپاتیک آلودنیای مکانیکی و هایپرآلژزنیای حرارتی نشان داده شد در گروه لیگاتور بندی آستانه تحریک درد نسبت به گروه کنترل به طور معناداری کمتر بود(05/0 ≤ P). میزان بیان ژن CDK5 در عصب سیاتیک در گروه لیگاتور بندی شده به طور معناداری (پاتولوژیک) نسبت به گروه کنترل افزایش نشان داد(05/0 ≤ P). بحث و نتیجه‌گیری: به نظر می‌رسد در پی یک دوره فعالیت کاهش یافته با مدل SNL ، افزایش پاتولوژیک بیان ژن CDK5 منجر به اثرات مخرب بر سیستم عصب و عضله، و ظهور نشانه‌های پاتولوژیکی نظیر، آتروفی عضلانی، عصبی، تسریع روند آپوپتوز و تخریب عصبی می‌گردد

Modified Ebulliometer for Measurement of Infinite Dilution Activity Coefficients

An existing design of an ebulliometer was modified by the addition of a vane-type magnetic pump to improve the performance of the ebull iometer at low pressures. The modified apparatus was used to determine the activity coefficients at infinite dilution of seven binary systems at three operating pressures each by the technique known as differential ebulliometry. The experimental results can be used to determine predictive model parameters which are of significant interest because of their ease of use and general applicability in phase equilibrium calculations.Chemical Engineerin

From laboratory experiments to design of a conveyor-belt dryer via mathematical modeling

A conveyor-belt dryer for picrite has been modeled mathematically in this work. The necessary parameters for the system of equations were obtained from regression analysis of thin-layer drying data. The convective drying experiments were carried out at temperatures of 40, 60, 80, and 100°C and air velocities of 0.5 and 1.5 m/sec. To analyze the drying behavior, the drying curves were fitted to different semi-theoretical drying kinetics models such as those of Lewis, Page, Henderson and Pabis, Wang and Singh, and the decay models. The decay function (for second order reactions) gives better results and describes the thin layer drying curves quite well. The effective diffusivity was also determined from the integrated Fick's second law equation and correlated with temperature using an Arrhenius-type model. External heat and mass transfer coefficients were refitted to the empirical correlation using dimensionless numbers (J h , J D = m · Re n ) and their new coefficients were optimized as a function of temperature. The internal mass transfer coefficient was also correlated as a function of moisture content, air temperature, and velocity

From laboratory experiments to design of a conveyor-belt dryer via mathematical modeling

A conveyor-belt dryer for picrite has been modeled mathematically in this work. The necessary parameters for the system of equations were obtained from regression analysis of thin-layer drying data. The convective drying experiments were carried out at temperatures of 40, 60, 80, and 100°C and air velocities of 0.5 and 1.5 m/sec. To analyze the drying behavior, the drying curves were fitted to different semi-theoretical drying kinetics models such as those of Lewis, Page, Henderson and Pabis, Wang and Singh, and the decay models. The decay function (for second order reactions) gives better results and describes the thin layer drying curves quite well. The effective diffusivity was also determined from the integrated Fick's second law equation and correlated with temperature using an Arrhenius-type model. External heat and mass transfer coefficients were refitted to the empirical correlation using dimensionless numbers (J h , J D = m · Re n ) and their new coefficients were optimized as a function of temperature. The internal mass transfer coefficient was also correlated as a function of moisture content, air temperature, and velocity

Application Of Nanofiltration Membrane In The Separation Of Amoxicillin From Pharmaceutical Wastewater

Separation of amoxicillin from pharmaceutical wastewater by nanofiltration (NF) membrane has been investigated in this study. For this purpose a membrane system including a polyamide spiral wound NF membrane was evaluated for the treatment of amoxicillin wastewater. The effects of operating conditions such as flow rate, pressure and concentration of amoxicillin and COD in the feed, on the efficiency of the membrane were evaluated. The permeation flux and rejection of amoxicillin and COD were the criteria for this evaluation. The rejection of the amoxicillin by the selected NF membrane was adequate and in most cases exceeded 97% whereas COD reached a maximum of 40% rejection and permeation flux was over 1.5 L/min.m2. The rise in pressure enhanced the transport rate of the solvents. Permeation flux of the NF membrane increased with increasing flow rates. Experimental data also indicated that concentration polarization existed in this membrane separation process. The stable permeation flux and high rejection of amoxicillin indicated the potential of NF for the recovery of amoxicillin from the pharmaceutical wastewater

Performance studies of mixed matrix membranes for gas separation : a review

Development of polymeric gasseparationmembranes is one of the fastest growing branches of membrane technology. However, polymeric materials are somewhat deficient in meeting the requirements of current membrane technology. Mixedmatrixmembrane (MMM), comprising rigid permeable or impermeable particles, such as zeolites, carbon molecular sieves, silica and carbon nanotubes, dispersed in a continuous polymeric matrix presents an interesting approach for improving the separation properties of polymeric membranes. In this approach, using properties of both the organic and inorganic phase, amembrane with good permeability, selectivity, mechanical strength, and thermal, chemical stability and processibility can be prepared. In this paper the performancestudies of MMM for gasseparation were critically reviewed. In addition, the materials selection and the preparation techniques of MMM were also discussed. Methodology in improving the interface defects in the MMM and its effect on the separationperformance have also been reviewed. The models for predicting the performance of MMM for gasseparation have been discussed in details and the future direction of research and development to fully exploit the potential usage of MMM was shown

Synthesis and Optimization of Chitosan Ceramic-Supported Membranes in Pervaporation Ethanol Dehydration

In the present work, ceramic-supported chitosan hybrid membranes were prepared for the pervaporation dehydration of ethanol. Mullite and combined mullite-alumina (50% alumina content) tubular low-cost ceramic supports were fabricated, and their influence on membrane performance was compared to a commercial α-alumina support. The membrane preparation parameters were different ceramic supports and the concentration of chitosan solution (varying from 2 wt.% to 4 wt.%). The supports and hybrid membranes were characterized by field emission scanning electron microscopy (FE-SEM) and contact angle measurements. The results show, with increasing chitosan concentration, the permeability decreases, and selectivity increases. It was also found that the separation factor decreases with increasing feed temperature and feed water content, while the permeation flux increases. The membrane that was coated on α-alumina support with a 3 wt.% chitosan concentration exhibited the best pervaporation performance, leading to a permeation flux and separation factor of 352 g·m−2·h−1 and 200 for 90 wt.% ethanol in feed at 60 °C, respectively