Adolescent ; Child ; Collagen Type I ; metabolism ; Extracellular Matrix ; metabolism ; Female ; Fibrillin-1 ; Fibrillins ; Heart Defects, Congenital ; metabolism ; pathology ; Humans ; Male ; Microfilament Proteins ; metabolism

OBJECTIVETo investigate the role of sodium-calcium exchanger (NCX) on ischemic preconditioning and pharmacological preconditioning.

METHODSCultured rat neonatal cardiomyocytes were randomly divided into 6 groups: (1) ischemia/reperfusion group (9 h ischemia followed by 1 h reperfusion, I/R), (2) ischemic preconditioning group (1.5 h ischemia/1 h reperfusion + I/R), (3) pharmacologic preconditioning group, adenosine (10 micromol/L) pretreated for 1 h + I/R, (4) calmodulin-dependent protein kinase II (CaMKII) inhibitor KN-93 (0.5 micromol/L for 0.5 h) + ischemic preconditioning group, (5) KN-93 + pharmacologic preconditioning group, (6) control group. The leakage of intracellular lactate dehydrogenase (LDH) in various groups was determined by biochemical autoanalyzer. Semi-quantitative RT-PCR was employed to measure the mRNA levels of sodium-calcium exchanger. Activity of sodium-calcium exchanger (Na(+)-dependent (45)Ca(2+) uptake) was measured by liquid scintillation counting.

RESULTS(1) Compared to the I/R group, the LDH leakages in both ischemic preconditioning group and pharmacologic preconditioning group were significantly reduced (P < 0.05) while significantly increased in the KN-93 + pharmacologic preconditioning group and the KN-93 + ischemic preconditioning group (P < 0.05). (2) The Na(+)-dependent (45)Ca(2+) uptake was significantly increased in the I/R group (P < 0.05) compared to control group and this increase could be significantly attenuated in ischemic preconditioning group and adenosine pretreatment group (P < 0.05). (3) The expression of NCX mRNA in I/R group was also significantly increased (P < 0.05) in the I/R group (P < 0.05) compared to control group and this increase could be significantly attenuated in ischemic preconditioning group and adenosine pretreatment group (P < 0.05), CaMKII inhibitor KN-93 significantly abolished these effects in preconditioning group (P < 0.05) and in adenosine pretreated group (P < 0.05).

CONCLUSIONNCX mediated the cardioprotective effects of ischemic preconditioning and pharmacological preconditioning in the neonatal cardiomyocytes I/R model.

Animals ; Calcium ; metabolism ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; antagonists & inhibitors ; Cells, Cultured ; Ischemic Preconditioning, Myocardial ; L-Lactate Dehydrogenase ; metabolism ; Myocardial Reperfusion Injury ; metabolism ; therapy ; Myocytes, Cardiac ; metabolism ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Sodium-Calcium Exchanger ; metabolism

Objective To detect the expression of matrix metallproteinases(MMPs) in aortic valve of children who suffered from rheumatic heart disease(RHD) and to explore the pathological role of MMPs in children′s rheumatic aortic valve disease.Methods RHD group composed of 18 aortic valves from children suffered from RHD.Controls were 8 children who were died accidentally without cardiovascular system diseases.Hematoxylin and eosin stain observing the histological characteristic of the 2 groups.Immunohistochemistry was used to detect expression of MMP2 and MMP9 on aortic valves in 2 groups.Results Hematoxylin and eosin stain showed:in RHD the valves′ structure were destroyed along with fibrous tissue proliferation,mucinous degeneration,collagen and fiber hyalinization,blood vessel and blood capillary proliferation,lymphocyte,plasmocyte,monocyte infiltration.Immunohistochemistry showed that MMP2 and MMP9 expression were significantly higher than those in the aortic of RHD(68.85?13.08,64.35?9.59) compared with control group(107.31?23.39,116.28?6.99)(t=3.92,10.18 all P

The present study aimed at investigating the effects of chronic multiple stress on learning and memory functions of rats. Adult male Wistar rats were randomly divided into stressed and control groups. Rats in the stressed group were irregularly and alternately exposed to the situation of vertical revolution, sleep deprivation, noise stimulation, and night illumination 6 h per day for 6 weeks to prepare a chronic multiple stressed model. Learning and memory performance of rats was measured by using Morris water maze first and Y-maze afterwards. Neurons in the dentate gyrus(DG), CA3 and CA1 regions of the hippocampus were stained by using Cresyl violet method and counted. The results showed that: (1) After chronic multiple stress, compared with the control rats, the escape latency to the hidden platform in Morris water maze was significantly shortened in stressed rats. In stressed and control groups, the escape latency periods were (15.89+/-9.15) s and (27.30+/-12.51) s, respectively, indicating that spatial memory of the stressed rats was stronger than that of the control ones. In brightness-darkness discrimination learning in the Y- maze, the correct trials and correct percentage of entering safe arm was remarkably increased in the stressed rats, the correct rates of stressed and control groups were (79.01+/-1.23)% and (66.12+/-1.61)%, respectively, indicating that brightness-darkness discrimination learning ability of the stressed rats was better than that of the control ones. (2) After chronic multiple stress, nerve cell density in DG, CA1 and CA3 of the hippocampus in stressed rats was higher than that of the control group, the cell densities in DG, CA1 and CA3 of the stressed and the control group were (223.78+/-26.52), (112.07+/-14.23) and (105.55+/-18.12) as well as (199.13+/-15.36), (92.89+/-13.69), and (89.02+/-15.77) respectively. These results suggest that the chronic multiple stress may enhance the capability of spatial memory and brightness-darkness discrimination learning of rats. Possible reasons for the chronic multiple stress-induced learning and memory enhancement of rats were also discussed.
Animals ; Hippocampus ; physiology ; Learning ; physiology ; Male ; Maze Learning ; Memory ; physiology ; Neuronal Plasticity ; physiology ; Rats ; Rats, Sprague-Dawley ; Spatial Behavior ; physiology ; Stress, Physiological ; physiopathology

BACKGROUNDThe effect of chronic stress on cognitive functions has been one of the hot topics in neuroscience. But there has been much controversy over its mechanism. The aim of this study was to investigate the effects of chronic multiple stress on spatial learning and memory as well as the expression of Fyn, BDNF and TrkB in the hippocampus of rats.

METHODSAdult rats were randomly divided into control and chronic multiple stressed groups. Rats in the multiple stressed group were irregularly and alternatively exposed to situations of vertical revolution, sleep expropriation and restraint lasting for 6 weeks, 6 hours per day with night illumination for 6 weeks. Before and after the period of chronic multiple stresses, the performance of spatial learning and memory of all rats was measured using the Morris Water Maze (MWM). The expression of Fyn, BDNF and TrkB proteins in the hippocampus was assayed by Western blotting and immunohistochemical methods. The levels of Fyn and TrkB mRNAs in the hippocampus of rats were detected by RT-PCR technique.

RESULTSThe escape latency in the control group and the stressed group were 15.63 and 8.27 seconds respectively. The performance of spatial learning and memory of rats was increased in chronic multiple stressed group (P < 0.05). The levels of Fyn, BDNF and TrkB proteins in the stressed group were higher than those of the control group (P < 0.05). The results of immunoreactivity showed that Fyn was present in the CA3 region of the hippocampus and BDNF positive particles were distributed in the nuclei of CA1 and CA3 pyramidal cells as well as DG granular cells. Quantitative analysis indicated that level of Fyn mRNA was also upregulated in the hippocampus of the stressed group (P < 0.05).

CONCLUSIONSChronic multiple stress can enhance spatial learning and memory function of rats. The expression of Fyn, BDNF and TrkB proteins and the level of Fyn mRNA are increased in the stessed rat hippocampus. These suggest that Fyn and BDNF/TrkB signal transduction pathways may participate in the process of the enhanced learning and memory during chronic multiple stress.

Animals ; Blotting, Western ; Brain-Derived Neurotrophic Factor ; genetics ; metabolism ; Hippocampus ; metabolism ; Immunohistochemistry ; Learning ; physiology ; Male ; Memory ; physiology ; Proteins ; genetics ; metabolism ; Proto-Oncogene Proteins c-fyn ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Wistar ; Receptor, trkB ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Stress, Physiological ; physiopathology

BACKGROUNDThe effect of chronic stress on cognitive functions has been one of the hot topic in neuroscience. But there has been much controversy over its mechanism. Such single stressor applied in the past could not simulate complicated living circumstances that people confronted with. The aim of this study was to investigate the effects of chronic multiple-stress on learning and memory as well as on the levels of calcium/calmodulin-dependent protein kinase II (CaMKII), calmodulin (CaM) mRNA, and cAMP-response element binding protein (CREB) mRNA in the hippocampus of rats.

METHODSThe rats were divided randomly into stressed and control groups. The stressed group was given chronic multiple-stress for 6 weeks to set up a chronic multiple-stressed model. The rats' performance of spatial learning and memory was tested using Morris Water Maze (MWM) and Y-maze. Meanwhile, the expressions of CaMKII, CaM mRNA and CREB mRNA of rats' hippocampus were detected by immunohistochemistry, Western blot and reverse transcription-polymerase chain reaction (RT-PCR), respectively. In addition, the width of synaptic cleft and the thickness of post-synaptic densities (PSD) were observed in the hippocampal CA3 region of rats by electron microscopy.

RESULTSAfter exposure to chronic multiple-stress for 6 weeks, the ability of learning and memory of the stressed group was higher than that of the control group (P < 0.05, P < 0.01). The width of synaptic cleft was smaller and the thickness of PSD was larger in the hippocampal CA3 region of the stressed group than in that of the control group (P < 0.01). The CaMK II immunostaining of the stressed group was stronger than that of the control group in the stratum radiatum and oriens of the hippocampal CA1 and CA3, especially in the stratum oriens. Quantitative analysis indicated that the expression of CaMK II, CaM mRNA, and CREB mRNA in the hippocampus of the stressed group was higher than that of the control group (P < 0.05, P < 0.01).

CONCLUSIONSThe capacity of learning and memory can be enhanced after chronic multiple-stress. The increased levels of CaMK II, CaM mRNA, and CREB mRNA may contribute to the enhancing effect of chronic multiple-stress on learning and memory.

Animals ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; Calcium-Calmodulin-Dependent Protein Kinases ; genetics ; Calmodulin ; genetics ; Chronic Disease ; Cyclic AMP Response Element-Binding Protein ; genetics ; Hippocampus ; metabolism ; ultrastructure ; Learning ; Male ; Memory ; Microscopy, Electron ; RNA, Messenger ; analysis ; Rats ; Rats, Wistar ; Stress, Physiological ; metabolism ; psychology ; Synapses ; ultrastructure

This paper makes an interpretation of the collection Acupuncture: how to improve the evidence base published by BMJ & BMJ Open. Studies show that the quality of randomized controlled trial (RCT) of acupuncture is low, and multivariable Meta-regression analysis fails to confirm most factors commonly believed to influence the effect of acupuncture. The methodological challenges in design and conduct of RCT in acupuncture were analyzed, and a consensus on how to design high-quality acupuncture RCT was developed. The number of acupuncture systematic reviews was huge but the evidence was underused in clinical practice and health policy, and a large number of western clinical practice guidelines recommended acupuncture therapy, but the usefulness of recommendations needed to be improved. In view of the problems in clinical research on acupuncture mentioned in this collection, combined with the analysis of the purpose of clinical research on acupuncture, perspectives, study types, as well as the relationship between evidence and clinical decision-making, a five-stage study paradigm of clinical research on acupuncture is proposed.
Acupuncture Therapy ; Acupuncture ; Research Design ; Consensus