Nerve growth factor downregulates c-jun mRNA and Caspase-3 in striate cortex of rats after transient global cerebral ischemia/reperfusion

BACKGROUND： Immediate early gene （lEG） c-jun is a sensitive marker for functional status of nerve cells. Caspase-3 is a cysteine protease, which is a critical regulator of apoptosis. The effect of exogenous nerve growth factor （NGF） on the expression of c-jun mRNA and Caspase-3 protein in striate cortex of rats with transient global cerebral ischemia/reperfusion （IR） is unclear. OBJECTIVE： To study the protective effect of exogenous NGF on the brain of rats with transient globa cerebral IR and its effecting pathway by observing the expression of c-jun mRNA and Caspase-3 protein. DESIGN： Randomized controlled animal trial SETTING： Department of Neural Anatomy, Institute of Brain, China Medical University MATERIALS：Eighteen healthy male SD rats of clean grade, aged 1 to 3 months, with body mass of 250 to 300 g, were involved in this study. NGF was provided by Dalian Svate Pharmaceutical Co.,Ltd. c-jun in situ hybridization detection kit, Caspase-3 antibody and SABC kit were purchased from Boster Biotechnology Co.. Ltd. METHODS： This trial was carried out in the Department of Neural Anatomy, Institute of Brain, China Medical University during September 2003 to April 2005. （1） Experimental animals were randomized into three groups with 6 in each： sham-operation group, IR group and NGF group.（2）After the rats were anesthetized, the bilateral common carotid arteries and right external carotid arteries of rats were bluntly dissected and bilateral common carotid arteries were clamped for 30 minutes with bulldog clamps. Reperfusion began after buldog clamps were removed. Normal saline of lmL and NGF （1×10^6 U/L） of 1 mL was injected into the common carotid artery of rats via right external carotid arteries in the IR group and NGF group respectively. The injection was conducted within 30 minutes, and then the right external carotid arteries were ligated. In the sham-operation group, occlusion of bilateral common carotid arteries and administration of drugs were omitted.GAll the rats were executed by decollation at 3 hours after modeling. The animals were fixed with phosphate buffer solution （PBS, 0.1 mol/L） containing 40 g/L polyformaldehyde, their brains were quickly removed. The coronal section tissue mass containing striate cortex about 3 mm before line between two ears was taken and made into successive frozen sections.（4）The expression of c-jun mRNA and Caspase-3 protein in striate cortex of global cerebral ischemia rats were detected with in situ hybridization, immunohistochemistry and microscope image analysis. （5）t test was used for comparing the difference of the measurement data. MAIN OUTCOME MEASURES：Comparison of the expression of lEG c-jun mRNA and Caspase-3 protein in striate cortex of brain of rats in each group. RESULTS：All the 18 SD rats were involved in the analysis of results. The c-jun mRNA and Caspase-3 protein positive reaction cells were found brown yellow in the striate cortex of rats, and most of them were in lamellas Ⅱ and Ⅲ, mainly presenting round or oval. The expression of c-jun mRNA and Caspase-3 protein in sham-operation group was weak or negative. The average gray value of c-jun mRNA and Caspase-3 protein in the IR group was significantly lower than that in the sham-operation group （49.52±4.13 vs. 95.48± 5.28; 74.73±4.29 vs. 162.38±9.16,P 〈 0.01）. The average gray value of c-jun mRNA and Caspase-3 protein in the NGF group was significantly higher than that in the IR group （63.96±4.25 vs.49.52±4.13; 83.98± 4.13 vs. 74.73±4.29, P〈 0.05）. CONCLUSION： NGF can protect ischemic neurons by down-regulating the expression of c-jun mRNA and Caspase-3 protein in striate cortex of global cerebral ischemia rats.

Theoretical study of interactions between striated cylindrical particles and membrane

The interaction of nanoparticles with cell membranes is of great importance because of their potential biomedical applications. In this paper, we investigate the adhesion of stripe-patterned cylinders to a fluid membrane with a full consideration of the Helfrich free energy. Three situations are considered: one striated cylindrical particle, two pure cylindrical particles, and two Janus cylindrical particles. It is found that, with the adhesion of a single sparse striated cylinder, there are a variety of steady-states with energy barriers and the stable state is determined by the pattern of the cylinder. However,when the particle is densely striped, it has no effect on the stable state. By comparing the wrapping degree of two cylindrical particles with that of a single cylindrical particle, we find that two pure cylindrical particles can promote or suppress their interaction with the membrane under different situations. However, two Janus cylindrical particles can only inhibit their interaction with the membrane. Besides, this interaction is related to a first-order transition which is a shallow-to-deep wrapping transition for two pure cylinders while it is a shallow-to-half wrapping transition for two Janus cylinders. Furthermore, the position where the transition happens as a function of adhesion energy is given for fixed membrane tension and the precondition of the transition is presented.

Actin-binding Rho activating protein is expressed in the central nervous system of normal adult rats

Previous studies show that actin-binding Rho activating protein （Abra） is expressed in cardiomyocytes and vascular smooth muscle cells. In this study, we investigated the expression profile of Abra in the central nervous system of normal adult rats by confocal immunofluorescence. Results showed that Abra immunostaining was located in neuronal nuclei, cytoplasm and processes in the central nervous system, with the strongest staining in the nuclei; in the cerebral cortex, Abra positive neuronal bodies and processes were distributed in six cortical layers including molecular layer, external granular layer, external pyramidal layer, internal granular layer, internal pyramidal layer and polymorphic layer; in the hippocampus, the cell bodies of Abra positive neurons were distributed evenly in pyramidal layer and granular layer, with positive processes in molecular layer and orien layer; in the cerebellar cortex, Abra staining showed the positive neuronal cell bodies in Purkinje cell layer and granular layer and positive processes in molecular layer; in the spinal cord, Abra-immunopositive products covered the whole gray matter and white matter; co-localization studies showed that Abra was co-stained with F-actin in neuronal cytoplasm and processes, but weakly in the nuclei. In addition, in the hippocampus, Abra was co-stained with F-actin only in neuronal processes, but not in the cell body. This study for the first time presents a comprehensive overview of Abra expression in the central nervous system, providing insights for further investigating the role of Abra in the mature central nervous system.

Changes in Myofibrillar and Mitochondrial Compartments during Increased Activity: Dependance from Oxidative Capacity of Muscle

Striated muscle tissue contains fibers with high oxidative capacity (heart muscle), higher oxidative capacity (type I and IIA fibers of skeletal muscle) and low oxidative capacity (type IIB/X fibers of skeletal muscle). Muscle fibers with higher oxidative capacity contain large mitochondria tightly packed with cristae as well as small forms of mitochondria containing relatively few cristae. The intensive development of the mitochondrial apparatus in the post-activity period reflects the adaptive processes, which is intended to supply the increased energy requirements of muscle fibers with higher oxidative capacity. Muscle fibers with low oxidative capacity contain significantly less mitochondria than fibers with higher capacity. It is typical to type IIB fibers that after intensive muscle activity there are damaged myofibrils in a relatively small area, some myofibrils are twisted and lose the connection with the neighboring structures. It is still not fully known how skeletal muscles with different oxidative capacity respond to an increased functional activity and what differences exist in these fibers between oxidative capacity and function of myofibrils. The aim of the present short review was to compare structural-functional changes in mitochondrial and myofibrillar compartments of heart and skeletal muscle fibers with different oxidative capacity and the effect of increased functional activity on the interaction of these compartments.

Global regularity of three-dimensional density patches for inhomogeneous incompressible viscous flow

Toward Lions’ open question in Lions(1996) concerning the propagation of regularity for density patch, we prove that the boundary regularity of the 3-D density patch persists by time evolution for inhomogeneous incompressible viscous flows, with the initial density given by(1-η)1?0+ 1?0c for some small enough constant η and some Wk+2p,domain ?0, p ∈]3, ∞[, and with the initial velocity satisfying some smallness condition and appropriate conormal regularities.

Global Regularity of 2-D Density Patches for Viscous Inhomogeneous Incompressible Flow with General Density:High Regularity Case

This paper is a continuation work of[26]and studies the propagation of the high-order boundary regularities of the two-dimensional density patch for viscous inhomogeneous incompressible flow.We assume the initial densityρ0=η11Ω0+η21Ω0^c,where(η1,η2)is any pair of positive constants andΩ0 is a bounded,simply connected domain with W^k+2,p(R^2)boundary regularity.We prove that for any positive time t,the density functionρ(t)=η11Ω(t)+η21Ω(t)^c,and the domainΩ(t)preserves the W^k+2,p-boundary regularity.

Bee sting keratopathy with retained stinger

This case report aims to report an uncommon case of bee sting keratopathy with retained stinger.A 55-year-old man presented with left cornea bee sting while gardening two days prior to first visit.He complained of severe eye pain with redness,tearing and blurring of vision.On examination,his right eye visual acuity was 6/6 and in left eye was hand movement.There was generalized conjunctival hyperemia and cornea showing significant descemet striae.A bee stinger with surrounding infiltration noted at 2 o'clock was associated with striate keratitis.It was deeply seated at the posterior third of cornea stroma near to paracentral area.Pupil was mid-dilated with absence of relative afferent pupillary defect.There was neither hypopyon nor cataract.The posterior segment could not be visualized due to severe corneal edema.However,B-scan ultrasound was normal.Bee stinger was removed under local anaesthesia on the day of presentation.Post-operatively,patient was administered with topical moxifloxacin and topical non steroidal anti-inflammatory drugs.Three weeks later,there was resolution of cornea infiltrate with improvement of striate keratitis and his vision was improved to 1/60.However,cornea edema did not regress but ended up with bullous keratopathy.The patient has undergone descemet-stripping automated endothelial keratoplasty and his vision was improved to 6/9.We recommend early stinger removal to reduce the possible sequelae of bee sting toxicity for better visual outcome.