Structural and physiological changes of the human body upon SARS-CoV-2 infection / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Since December 2019, the novel coronavirus (severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)) has spread to many countries around the world, developing into a global pandemic with increasing numbers of deaths reported worldwide. To data, although some vaccines have been developed, there are no ideal drugs to treat novel coronavirus pneumonia (coronavirus disease 2019 (COVID-19)). By examining the structure of the coronavirus and briefly describing its possible pathogenesis based on recent autopsy reports conducted by various teams worldwide, this review analyzes the possible structural and functional changes of the human body upon infection with SARS-CoV-2. We observed that the most prominent pathological changes in COVID-19 patients are diffuse alveolar damage (DAD) of the lungs and microthrombus formation, resulting in an imbalance of the ventilation/perfusion ratio and respiratory failure. Although direct evidence of viral infection can also be found in other organs and tissues, the viral load is relatively small. The conclusion that the injuries of the extra-pulmonary organs are directly caused by the virus needs further investigation.

Different internal fixation methods of oblique lateral interbody fusion: a finite element analysis / 医学研究生学报

ObjectiveThere is still controversy about which internal fixation method should be used in oblique lateral interbody fusion (OLIF). This paper aims to compare the biomechanical stability of OLIF with different internal fixation methods.MethodsA 31-year-old healthy male volunteer was selected to have a 64-slice spiral CT scan of his lumbar spine. Mimics 19.0, Geomagic Studio 2013, SolidWorks 2017 and other software were used to build a three-dimensional model of L3-L5, and OLIF surgery was simulated to build OLIF finite element models with five different fixation methods: pedicle screw (PS), lateral single rod screw (LSRS), lateral double rod screw (LDRS), lateral single rod screw+ipsilateral translaminar facet screw (LSRS+ITLFS), lateral single rod screw+contralateral translaminar facet screw (LSRS+CTLFS). After validating the validity of the model, the motion modes of spinal flexion, extension, lateral bending and rotation were simulated, and the fixed segment activity and stress distribution characteristics of each model were compared.ResultsIn terms of fixed segment activity, PS had the best fixation effect, and its range of motion (ROM) was the smallest in all 6 modes. The ROM of the vertebral body was maximized when the LSRS was fixed in all directions. LSRS+ITLFS, LSRS+CTLFS and PS had the similar ROM. In terms of maximum stress of cage, PS had the minimum one except in the left bending. LSRS+ITLFS had little stress in all directions except in flexion; LSRS+CTLFS had little stress in all directions except in extension. In terms of the maximum stress in internal fixation, PS had the least one in all directions; LSRS+CTLFS followed, and the maximum stress appeared in extension and right bending (123.05MPA and 91.74MPA, respectively).ConclusionIn OLIF surgery, PS has the best biomechanical effect. LSRS+CTLFS has the similar effect and its clinical operation is simple with relatively small surgical injury, thus providing a reference for clinical choice.

Establish mouse osteoblast -osteoclast cell co-culture system in a Transwell chamber / 中国骨伤

<p><b>OBJECTIVE</b>To establish osteoblast-osteoclast cell co-culture system in a Transwell chamber, and detect cell viability of osteoblasts and osteoclasts in system.</p><p><b>METHODS</b>Osteoblast MC3T3-E1 and mouse monocytes RAW264.7 were cultivated in vitro. RANKL-induced mouse RAW264.7 monocytes differentiated into mature osteoclasts, osteoblast-osteoclast cell co-culture system was established in Transwell chamber. Cell activity of osteoblasts and osteoclasts were detected by CCK-8 experimenting, Alizarin Red staining, TRAP staining. The expression of OPG, ALP, RANKL, TGF-b1 gene and RANKL protein in osteoblast MC3T3-E1 were detected by PCR, Western-Blot methods. Also, the expression of RANK, NF-κB in gene and protein level in osteoclast were measured through the same method respectively.</p><p><b>RESULTS</b>The co-culture system of Mouse MC3T3-E1 cells and RAW264.7 cell were established in Transwell chamber. Co-culture system affected cell division activities of osteoblasts and osteoclasts. Differentiation of osteoblasts were increased, while differentiation of osteoclast division were slight decreased under microscope observation. OPG (0.65±0.08) and ALP (0.16±0.01) gene expression of co-culture system were less than single culture OPG(1.00±0.08) and ALP (1.01±0.16); TGF-b1(4.42±0.21) and RANKL(4.12±1.04) of osteoblasts in co-culture system were higher than TGF-b1(1.00±0.10) and RANKL(1.00±0.09) under single culture. However, gene expression of RANK(0.63±0.06) and NF-κB(0.64±0.08) in co-culture system were decreased than RANK(1.00±0.08) and NF-κB(1.00±0.09), in single culture, and had significant differences. Similarly, protein expression of OPG(0.43±0.05) and NF-κB(0.59±0.05) of co-culture system were less than OPG(0.84±0.06) and NF-κB(1.13±0.03) of single culture. While RANKL protein expression (0.54±0.03)of co-culture system was more than single culture RANKL(0.31±0.03), and had statistically differences, which was in agreement of the trend of gene expression change.</p><p><b>CONCLUSIONS</b>Co-culture system of mouse MC3T3-E1 cells and RAW264.7 cell was viable in Transwell chamber, and the activity of osteoblasts is higher than osteoclasts in co-culture system.</p>

Advances in Diagnosis and Treatment of Lymphocele After Laparoscopic Lymphadenectomy / 中国微创外科杂志

Gynecological malignant tumors, including cervical tumors, endometrial tumors and ovarian tumors, can be treated by laparoscopy.Lymphocele is one of the common postoperative complications after pelvic lymphadenectomy.However, lymphocele is not fatal, and the clinical symptoms were associated with the lymphocele size.Hence, we reviewed advances in diagnosis and treatment of lymphocele after laparoscopic lymphadenectomy.

Analysis of clinical characteristics of 20 patients with pyogenic spondylitis / 中国骨伤

<p><b>OBJECTIVE</b>To investigate the diagnostic value of clinical manifestation, laboratory examination and imaging changes for pyogenic spondylitis and to summarize the clinical characteristics of patients with pyogenic spondylitis.</p><p><b>METHODS</b>The clinical data, of 20 patients with pyogenic spondylitis were diagnosed by histopathological examination from March 2012 to March 2015, were retrospectively analyzed. There were 9 males and 11 females, aged from 43 to 72 years old with an average of 58.9 years. Included 3 cases of cervical vertebrae, 7 cases of thoracic vertebrae, 10 cases of lumbar vertebrae. Patients of blood analysis, erythrocyte sedimentation rate(ESR), C reactive protein(CRP), X rays, CT and MRI were performed before treatment. Visual analogue scale (VAS) was used to evaluate the pain of patients suffering from vertebral pain.</p><p><b>RESULTS</b>All the patients had suffered from vertebral pain before treatment. VAS was 9 points in 4 cases, 8 points in 6 cases, 7 points in 1 case, 3 points in 6 cases, and 2 points in 3 cases. Among them, 7 patients complicated with neurological symptoms, 11 with aggravating night pain, 10 with fever. WBC and Neutrophil count (NEU) of 5 cases were increased and other 15 cases were normal;CRP of 19 cases were increased and 1 case was normal;ESR of all 20 cases were increased. X rays showed the intervertebral space narrowing in all 20 cases, 13 cases complicated with destruction of vertebral body; CT showed the lesions of vertebral body in the 20 cases and complicated with destruction, sclerosis of sclerotin; MRI showed that the lesions of the vertebral body in the T1 image had uneven medium low signal, in the T2 image of the 16 cases had uneven high signal and 2 cases had uniform and high signal, 2 cases had main high signal compliated with mixed signal. Thirteen patients underwent surgical treatment and 7 patients received conservative treatment, and the patients left hospital while VAS had significantly improved after treatment.</p><p><b>CONCLUSIONS</b>Pyogenic spondylitis is easy to be misdiagnosed or missed in clinic. It can be combined with the clinical manifestations, laboratory examination and imaging characteristics in order to make a definite diagnosis for purulent spondylitis in early.</p>

Analysis on 21 cases of chylous fistula after neck lymph nodes dissection / 重庆医学

Objective To discuss the prevention and management method for chylous fistula after neck lymph node dissec‐tion .Methods Totally 1 793 cases of neck lymph node dissection in this department from January 2005 to September 2014 were retrospectively analyzed .The clinical data in the cases of chylous fistula occurred after operation were summarized .Results Twenty one cases of chylous fistula occurred ,accounting for 1 .17% ,in which 13 cases were cured by the local compressed bandaging and continuous negative pressure drainage;5 cases adopted the conventional method for 2-3 d ,but under the ineffective condition ,then they were treated by combining with somatostatin pumping (somatostatin 6 mg+0 .9% normal saline 48 mL ,2 mL/h ,lasting for 24 h ,for successive 2-3 d) and finally cured;3 cases were cured after reoperation .Conclusion Prevention is the best treatment for chylous fistulas ,local compression bandage plus continuous negative pressure drainage is the main method for treatment of chylous fistulas after neck dissection .The combined therapy with somatostatin can increase the close rate of chylous fistulas;for the patients with long persistent time ,large drainage volume and invalid conservative therapy should adopt the remedial measure of operation .

Clinical significance of increased plasma IGF-1 in type 2 diabetic patients with malignant tumor / 重庆医学

Objective To test plasma insulin‐like growth factor 1(IGF‐1) level in type 2 diabetic patients with malignant tumor , and make comparison with diabetic patients and normal patients .To discuss the significance of detection of plasma IGF‐1 level in type 2 diabetes in screening early malignant tumor .Methods Plasma IGF‐1 level were determined in type 2 diabetes among malig‐nant tumor group ,type 2 diabetes ,and normal control group ,and statistical comparison was made between the three groups .Results the plasma levels of IGF‐1 of type 2 diabetes mellitus ,type 2 diabetes mellitus with malignant tumor were significantly lower than normal group(P<0 .05) .And the plasma level of IGF‐1 in type 2 diabetes mellitus with malignant tumor group was obviously high‐er than that of type 2 diabetic group(P<0 .05) .Plasma IGF‐1 ,FBG ,HbA1c and 2 HBG level are risk factors for tumor .The level of FIns is a protective factor for tumor .Conclusion Type 2 diabetes is closely related to the malignant tumor ,and the plasma levels of IGF‐1 is a risk factor for tumor .

Effects of total flavones of Elsholtzia splendens in isolated ischemia/reperfusion rat hearts / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the influence of total flavonoids of Elsholtzia splendens (TFES) on isolated ischemia/reperfusion rat hearts and its underlying mechanisms.</p><p><b>METHODS</b>Hearts isolated from male SD rats were perfused on the Langendorff apparatus and subjected to global ischemia for 30 min followed by 120 min of reperfusion. The cardiac infarct size was measured by TTC staining. Hemodynamic parameters and the level of lactate dehydrogenase (LDH) in the coronary effluent were measured. Absorbance at 520 nm was determined in isolated cardiac mitochondria exposed to 200 micromol/L CaCl2 to detect the opening of the mitochondrial permeability transition pore.</p><p><b>RESULTS</b>Pretreatment with TFES (1, 10, 100 microg/ml) for 5 min decreased infarct size and LDH release and improved the recovery of the left ventricular developed pressure. In mitochondria, the decrease of absorbance at 520 nm evoked by CaCl2 was greatly inhibited by TFES.</p><p><b>CONCLUSION</b>TFES prevents myocardial ischemia/reperfusion injury, and this cardioprotective effect is probably via inhibiting mitochondrial permeability transition pore opening.</p>

Exploration on sensation positioning method of heat-sensitive moxibustion: the inheritance and development of ashi method / 中国针灸

From original concept and literature of acupoint, the concept and clinical significance of ashi method is discussed, which clarifies that the essence of ashi method is to locate the acupoints by patients' sensitivity on force. The clinical application of heat-sensitive moxibustion has illustrated that positioning method of this therapy is based on the appearance of heat-sensitive moxibustion sensation. Although both types are based on patients' feeling, positioning method of heat-sensitive moxibustion stands on a new angle and uses a new method to locate acupoint. Therefore, it is believed that the positioning method of heat-sensitive moxibustion is the inheritance and development of ashi method.

The clinical application research on the island pedicled pectoralis major muscle flap in repairing of the tissue defects after the operation of head and neck malignant tumors / 重庆医学

Objective To investigate the primary repair methods and efficacy of island pedicled pectoralis major muscle flap in soft tissue defect after the operation of head and neck malignant tumors .Methods From April 2011 to September 2012 ,27 patients from this hospital who underwent primary repair using island pedicled pectoralis major muscle flap after a head and neck extensive soft tissue defect were investigated ,including 11 cases of tongue cancer defect ,2 cases of parotid gland defect ,3 cases of gum cancer defect ,2 cases of oropharyngeal cancer defect ,9 cases of floor of the mouth cancer defect .Results 27 patients were safety in periop-erative ,27 cases of island pectoralis major muscle flap survived ,patients were satisfied with both the appearance and function .There was postoperative neck hematoma in 1 patient ,it was eliminated through timely remove the hematoma and hemostasis completely ;There was 1 case of removing the epidermal necrolysis skin as flap necrosis ,while it was acceptable efficacy as the muscle flap sur-vival and surface granulation repaired .Conclusion Island pectoralis major muscle flap obtains unique advantages in repairing a large area of soft tissue defect in head and neck cancer patients after operation ,such as abundant of tissue ,a constant arterial anatomy of thoracoacromial ,easy to operate ,rich blood supply ,strong resistance to infection ,high survival rate and so on .A fine surgery opera-tion is the key of island pectoralis major muscle flap survival .

Effect of S-allyl-L-cysteine on isolate heart subject to ischemia/reperfusion / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effect of S-allyl-L-cysteine (SAC) on isolated rat heart subject to ischemia/reperfusion(I/R) injury and the mechanisms.</p><p><b>METHODS</b>The isolated perfused rat hearts on a Langendorff apparatus were subjected to global ischemia for 30 min and followed by 120 min of reperfusion. Hemodynamic index, the production of formazan and the level of lactate dehydrogenase (LDH) in the coronary effluent were determined. Superoxide dismutase (SOD) and reactive oxygen species (ROS) in myocardial homogenates were measured.</p><p><b>RESULTS</b>Compared with I/R group, the hemodynamics were greatly improved, the production of formazan was increased, and LDH level in effluent was reduced in SAC group. SAC improved the SOD activity and significantly decreased the level of ROS. In addition, threonine (Thr) attenuated the protective effect of SAC significantly.</p><p><b>CONCLUSION</b>SAC has protective effect against myocardial ischemia/reperfusion injury on rats. The possible mechanism is that SAC be transported into the cell through alanine-serine-cysteine-transporter 1 (ASCT-1) improves SOD activity and reduces the level of ROS.</p>

Expression and function of autophagy after ischemia/reperfusion in rats hippocampus neuron / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To explore the expression of autophagy after ischemia/reperfusion and its possible function in rats hippocampus neurons.</p><p><b>METHODS</b>After 2 hours oxygen-glucose deprivation and different periods time of reperfusion (OGD/R) treatment in primary hippocampal neurons, neuron viability was evaluated by MTT assay, specific structure of autophagosome and specific protein of autophagy microtubule-associated protein 1 light chain 3 B (LC3B) were detected by transmission electron microscope and immunofluorescence respectively. The inhibitor of autophagy 3-Methyladenine (3-MA) was also used to exam the viability of neurons.</p><p><b>RESULTS</b>Treatment by OGD/R markedly reduced neuronal viability. Compared to the control group, autophagy existed in different time periods after OGD/R shown both in transmission electron microscope and immunofluorescence. Application of 3-MA significantly reduced neuronal viability.</p><p><b>CONCLUSION</b>Oxygen-glucose deprivation can activate autophagy in rat hippocampus neurons, which may resist the injury during ischemia/reperfusion.</p>

Luteolin reduces cardiac dysfunctions in streptozotocin-induced diabetic rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effects of luteolin (Chinese Traditional Medicine) on cardiac functions and mitochondrial oxidative stress in streptozotocin (STZ)-induced diabetic rats.</p><p><b>METHODS</b>Male SD rats were randomly divided into a normal control group, a luteolin control group, a diabetic group, and diabetic groups orally administered with a low dose (10 mg/(kg x d)) or a high dose of luteolin (100 mg/ (kg x d)) for eight weeks. The body weight, blood glucose, cardiac functions, left ventricular weight, myocardial collagen and reactive oxygen species (ROS) levels were assayed. The cardiac mitochondrial ROS level, superoxide dismutase (SOD) activity and the mitochondrial swelling were measured.</p><p><b>RESULTS</b>Treatment with luteolin had no effect on the blood glucose but reduced the losing of body weight in diabetic rats. High dose of luteolin markedly reduced the ratio of ventricular weight and body weight, increased the left ventricular develop pressure, and decreased the left ventricular end diastolic pressure in diabetic rats. The myocardial levels of ROS and collagen, the cardiac mitochondrial ROS level, and the mitochondrial swelling in diabetic rats were all markedly reduced by high dose of luteolin. Furthermore, high dose of luteolin significantly increased the mitochondrial SOD activity in diabetic rat hearts.</p><p><b>CONCLUSION</b>Treatment with luteolin for 8 weeks markedly improves the cardiac function, which may be related to reducing mitochondrial oxidative stress and mitochondrial swelling in diabetic rats.</p>

Study of the effects of Auricularia auricular polysaccharide on local ischemia/reperfusion injury in rat / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the influence of Auricularia Auricular polysaccharide (APP) on acute cerebral injury induced by ischemia/reperfusion in rats and its underlying mechanism.</p><p><b>METHODS</b>Adult male SD rats were intragastrically pretreated with AAP at a low (50 mg/kg) or high (100 mg/kg) dose once a day for 20 days before operation. Rats intraperitoneally injected with ginkgo biloba extract (EGb671) were taken as positive control. Focal ischemia was achieved by middle cerebral artery occlusion (MCAO) on the right side for 60 min. After 24 hrs of reperfusion, the nerve function defects were recorded by Longa's score and the brain infarct sizes were measured by 2,3,5-Triphenyl-tetrazolium-chlor (TTC) staining. Apoptotic neurons were detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining after 48 h of reperfusion. The levels of oxidative stress was determined via the mitochondria-generated reactive oxygen species (ROS).</p><p><b>RESULTS</b>AAP treatment decreased Longa's score, brain infarct size, apoptotic neurons and mitochondria-generated ROS in a dose-dependent manner. AAP at 100 mg/kg gave a better performance compared with EGb671 on all parameters examined.</p><p><b>CONCLUSION</b>AAP treatment protected rat brain from focal ischemia/reperfusion injury by its anti-oxidative effect and worked better than EGb671.</p>

Inhibitory effect of VPA on multiple myeloma U266 cell proliferation and regulation of histone acetylation / 中国实验血液学杂志

This study was aimed to investigate the effects of sodium valproate (VPA) on the proliferation and regulation of histone acetylation of multiple myeloma cell line U266. U266 cells were treated with VPA. Cell proliferation was determined by CCK-8 assay, and cell cycle were analyzed by flow cytometry (FCM). The expression level of HDAC1 mRNA was detected by RT-PCR, and the protein levels of HDAC1 and histone H3, H4 acetylation was detected by Western blot. The results showed that the VPA inhibited the proliferation of U266 cells in concentration-and time-dependent manners.After exposure to different concentrations of VPA for 48 hours, the proportion of G(0)/G(1) cells increased, while the proportion of S phase cells decreased. The cell cycle was arrested obviously in G(0)/G(1) phase (p < 0.05). The expression of HDAC1 mRNA was inhibited, and the protein level of HDAC1 was down-regulated, while the histone H3/H4 acetylation was up-regulated in U266 cells. It is concluded that the VPA can inhibit cell proliferation of U266 and induce G(0)/G(1) phase arrest. The increase of histone H3/H4 acetylation resulting from inhibiting HDAC1 by VPA might be considered as a possible mechanism.

Partial endothelium-dependent vasorelaxation of crocetin and its mechanism / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the vasorelaxation effect of crocetin (CCT) and its mechanism.</p><p><b>METHODS</b>Isolated aortic rings from Sprague-Dawley rats were mounted in the organ bath system. The tension of the aorta was recorded.</p><p><b>RESULT</b>CCT significantly provoked concentration-dependent relaxation in both endothelium-intact and-denuded aortic rings pre-constricted by phenylephrine (10⁻⁵ mol/L), and the vasorelaxation in endothelium-intact aortic rings was stronger than that in endothelium-denuded ones. CCT had no significant effects on aortic rings pre-constricted with KCl (6 × 10⁻² mol/L). Pretreatment with eith L-NAME (10⁻⁴ mol/L), an inhibitor of nitric oxide synthase (NOS), or indomethacin (10⁻⁵ mol/L), an inhibitor of cyclooxygenase, for 30 min significantly attenuated the relaxation of endothelium-intact aortic rings induced by CCT. Besides, both tetraethylammonium (a Ca²(+)-activated K(+) channel inhibitor, 5 × 10⁻³ mol/L) and 4-aminopyridine (a voltage-sensitive K(+) channel inhibitor, 10⁻³ mol/L), but not the ATP-sensitive K(+) channel inhibitor glibenclamide (3 × 10⁻⁶ mol/L), significantly attenuated CCT-induced relaxation in endothelium-denuded aortic rings.</p><p><b>CONCLUSION</b>CCT had partial endothelium-dependent relaxation in rat aortas, which may be mediated by activating the endothelial NOS-NO and cyclooxygenase-prostacyclin pathways. The endothelium-independent relaxation in rat aortas induced by CCT may be mediated by Ca²(+)-activated K(+) channels and voltage-sensitive K(+) channels.</p>

Electrophysiological effect of atorvastatin on isolated rat hearts injured by ischemia/reperfusion / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the myocardial electrophysiological effect and its underlying mechanisms of atorvastatin (Ator) on isolated rat hearts injured by ischemia/reperfusion (I/R).</p><p><b>METHODS</b>Isolated SD rat hearts were mounted on Langendorff system, and a local I/R was induced by ligation (30 min) and release (15 min) of the left anterior descending artery. During the reperfusion period, the effect of Ator on diastolic excitation threshold (DET), effective refractory period (ERP) and ventricular fibrillation threshold (VFT) on rat heart were measured.</p><p><b>RESULT</b>Compared with the control group, medium concentration of Ator prolonged the ERP in normal rat hearts; low, medium and high concentration of Ator significantly inhibited the decrease of DET, ERP and VFT induced by I/R. However, pretreatment with L-NAME cancelled these cardiac electrophysiological effects of Ator.</p><p><b>CONCLUSION</b>Ator reduced electrophysiological alteration induced by I/R in isolated rat hearts, which may be mediated by activating nitric oxide pathway to enhance the myocardial electrophysiological stability.</p>

Investigation on the mechanisms of p15INK4B gene demethylation by valproate in Molt-4 cells / 中华血液学杂志

<p><b>OBJECTIVE</b>To study the antitumour effects of sodium valproate (VPA) on the proliferation, differentiation and cell cycle of Molt-4 cell and to investigate its demethylation mechanisms.</p><p><b>METHODS</b>After Molt-4 cells trated with VPA at different concentrations, cell viability and growth curve were assessed by MTT assay. Cell cycle changes were analyzed by flow cytometry. The expression level of p15, DNA methyltransferase 1 (DNMT-1), DNMT3A and 3B mRNA were detected by RT-PCR and the methylation level was detected by hn-MSPCR.</p><p><b>RESULTS</b>VPA significantly inhibited the proliferation of Molt-4 cells. After 48 h culture with 5.0 mmol/L VPA, the percentages of Molt-4 cells in G(0)/G(1) phase was (66.87 ± 3.31)% and in S phase was (8.47 ± 2.56)%, while in control group, the cells in G(0)/G(1) phase increased and in S phase decreased significantly. The p15 gene in Molt-4 cells failed to express due to its hypermethylation. The expression level of p15 gene mRNA increased significantly after exposure to VPA for 48 h. As compared with control group, the expression of DNMT-1 was down-regulated in a dose-dependent manner. The expression level of DNMT3B decreased at 10.0 mmol/L concentration.</p><p><b>CONCLUSION</b>VPA has a demethylation effect on p15 INK4B gene by inhibiting the DNMT-1 and DNMT3B gene activities to recover p15 gene activity, which arrests Molt-4 cell in G(0)/G(1) phase.</p>

Myocardial protective effect of acetylcholine against ischemia/reperfusion injury and its underlying mechanism / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To determine whether the caidioprotection of acetylcholine (ACh) against ischeniia/reperftision (I/R) injury is re-kited to mitochondrial permeability transition pore (MEW) and mitochondrial AW-sensitive potassium channel (mitoK(ATP)).</p><p><b>METHODS</b>Male Sprague-Dawley rats were used for Langendorif isolated bean perkision. The hearts were subjected to global ischemia for 30 mm followed by 120 rein of reperfusion and the left ventricular hemodynaniic parameters were measured. Formazan, a product of 2,3, 5-triphenyl-tetrazolium chloride (TTC), which is proportional to myocardial viability, was measured at 490 nm, and the level of lactate dehydrogenase (LDH) in the coronary effluent was measured to evaluate the cardiac injury.</p><p><b>RESULTS</b>The pretreatment with ACh (0.1 mol/L, 5 mm) before I/R markedly increased myocardial formazan content, reduced LDH release, improved the recovery of the left veritficular developed pressure, +/- dP/dtmax, and rate pressure product (left ventricular developed pressure multiplied by hean rate) and attenuated the decrease of coronary flow during reperfusion. The opener of MPTP, atiractyloside (20 mmoL/L) or the inhibitor of mitoK(ATP), 5-hydroxydecanoate (100 micromol/L) abolisbed the beneficial effect of ACh.</p><p><b>CONCLUSION</b>In the isolated rat bean, ACh protects myocardium against ischemia/reperfusion injury via inhibiting the opening of MPTP and increasing the opening of mitoKATP in heart.</p>

Auricularia auricular polysaccharide protects myocardium against ischemia/reperfusion injury / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To determine whether auricularia auricular polysaccharide (AAP) protects heart against ischemia/reperfusion (1/ R) injury and its underlying mechanisms.</p><p><b>METHODS</b>Male Sprague-Dawley rats, pretreated with AAP (50, 100, 200 mg/(kg x d), gastric perfusion) for 4 weeks, were used for Langendorff isolated heart perfusion. The hearts were subjected to global ischemia for 30 min followed by 120 min of reperfusion and the left ventricular hemodynamic parameters were measured. Formazan, a product of 2, 3, 5-triphenyl-tetrazolium chloride (TTC), which is proportional to myocardial viability, was measured at 490 nm, and the level of lactate dehydrogenase (LDH) in the coronary effluent was measured to evaluate the cardiac injury. The cardiac malondialdehyde (MDA), a product of lipid peroxidation, and superoxide dismutase (SOD) activity were determined after myocardial I/R.</p><p><b>RESULTS</b>The pretreatment with AAP at 50, 100, 200/(kg d) for 4 weeks before I/R increased myocardial formazan content, reduced LDH release, improved the recovery of the left ventficular developed pressure, maximal rise rate of left ventricular pressure, and rate pressure product (left ventricular developed pressure multiplied by heart rate) attenuated the decrease of coronary flow during reperfusion. The cardiac protective effect of high dose AAP was more potent than that of compound radix salviae miltiorrhizae (CRSM, 4 ml/(kg x d), gastric perfusion for 4 weeks). Pretreatment with AAP (100 mg/(kg x d)) markedly inhibited the increase of MDA level and the decrease of SOD activity induced by I/R in myocardium.</p><p><b>CONCLUSION</b>The findings indicate that in the isolated rat heart, AAP protects myocardium against ischemia/reperfusion injury via enhancing the activity of SOD and reducing lipid peroxidation in heart.</p>