The effects of intermittent hypobaric hypoxia on myocardial ischemia/reperfusion injury and ZFP580 expression / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To elucidate whether ZFP580 is involved in the cardioprotective effects of intermittent hypobaric hypoxia (IHH) against myocardial ischemia/reperfusion (I/R) injury.</p><p><b>METHODS</b>Thirty two male Wistar rats were randomly divided into 2 groups (n = 16): normoxia control group and IHH preconditioning group. Rats in IHH group were exposed in a hypobaric chamber (equivalent to an altitude of 5 000 m) for a 6 h period each day for 42 d. Plasma was collected and lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) were measured after 2 h of myocardial I/R injury. ZFP580 protein expression in myocardial tissue was assayed by Western blot. Other 8 rats in each group were used to evaluate I/R-induced cardiac infarction by TTC staining. Lentivirus-mediated gene transfection was performed in H9c2 cells 72 h prior to simulated ischemia/reperfusion (SI/R) exposure. The degree of cell apoptosis was determined by annexin V/7-AAD staining and flow cytometry analysis.</p><p><b>RESULTS</b>Compared with normoxia control group, adaptation to IHH attenuated infarct size and plasma leakage of LDH and CK-MB. In addition, ZFP580 expression in the myocardium was up-regulated by IHH. The results of gene transfection showed that ZFP580 overexpression significantly inhibited cells apoptosis induced by SI/R.</p><p><b>CONCLUSION</b>Our findings demonstrate that the cardioprotective effect of IHH against I/R injury is mediated via ZFP580, a novel transcription factor, with anti-apoptotic roles in myocardial cells.</p>

Establishment of heat acclimatization model in rabbits and its pathophysiological characteristics / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To establish an effective and stable rabbit heat acclimatization model for the experiment of heat acclimatization mechanisms.</p><p><b>METHODS</b>Sixteen healthy male rabbits were divided into heat acclimatization group and control group randomly (n = 8). Heat acclimatization (HA) group was kept in simulation chamber with dry bulb temperature of (36 +/- 1) degrees C, wet bulb temperature of (29 +/- 0.5) degrees C, black-bulb temperature of (40 +/- 1.0) degrees C, 100 min/day for 21 days. Control group was kept in the room with temperature of 20 degrees C and relative humidity < 60% during 20 days, then removed into simulation chamber on day 21 to estimate and monitor the rectal temperature together with the heat acclimatization group. Venous blood of control and heat acclimatization group before and after heat exposure on the 1st day, 11th day and 21st day were collected to detect levels of tumor necrosis factor-alpha (TNF-alpha), interleukin 6 (IL-6) and heat shock protein 70 (HSP70) by ELISA analysis.</p><p><b>RESULTS</b>(1) Rectal temperature: There was no significant change in control group during 21 days. In heat acclimatization group, it increased (2.07 +/- 0.43) degrees C after the 1st exposure, and increased (1.78 +/- 0.37) degrees C after the 11th exposure, the range of increasing decreased (0.29 +/- 0.09) degrees C. After the 21st exposure, it increased (1.52 +/- 0.29) degrees C, which was (0.55 +/- 0.14) degrees C lower than that of the 1st (P < 0.05),and (0.53 +/- 0.14) degrees C lower to that of the control group under 1st heat stress (P < 0.05); (2) The level of TNF-alpha after the 1st exposure increased significantly (P < 0.05), but didn't raise along with the exposure times. And fell back to the original level after the 11th and 21st exposure. Compared with control group, the level of IL-6 increased after the 1st, 11th and 21st exposure (P < 0.05), and maintained highly after the 11th and 21st exposure. Compared with the control group, the level of HSP70 increased dramatically with the heat exposure times. Significant increasing of (HSP70) could be detected after the 11th and 21st exposure (P < 0.05), but there was no difference to that of the 1st exposure.</p><p><b>CONCLUSION</b>Prolonged or repeated exposure to heat stressful environmental conditions can reduce the physiological strain, improve heat tolerance, elicits heat acclimatization.</p>

Four-week simulated weightlessness increases the expression of atrial natriuretic peptide in the myocardium / 生理学报

One of the major circulatory changes that occur in human during space flight and simulated weightlessness is a cerebral redistribution of body fluids, which is accompanied by an increase of blood volume in the upper body. Therefore, atrial myocardium should increase the secretion of atrial natriuretic peptide (ANP), but the researches lack common conclusion until now. The present study was to investigate the expression level of ANP in simulated weightlessness rats, and to confirm the changes of ANP by observing the associated proteins of soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs). The tail-suspended rat model was used to simulate weightlessness. Western blots were carried out to examine the expression levels of ANP and SNARE proteins in atrial and left ventricular myocardium. The results showed that ANP expression in atrial myocardium showed an increase in 4-week tail-suspended rats (SUS) compared with that in the synchronous control rats (CON). We only detected a trace amount of ANP in the left ventricular myocardium of the CON, but found an enhanced expression of ANP in left ventricular myocardium of the SUS. Expression of VAMP-1/2 (vesicle associated SNARE) increased significantly in both atrial and left ventricular myocardium in the SUS compared with that in the CON. There was no difference of the expression of syntaxin-4 (target compartment associated SNARE) between the CON and SUS, but the expression of SNAP-23 showed an increase in atrial myocardium of the SUS compared with that in the CON. Synip and Munc-18c as regulators of SNAREs did not show significant difference between the CON and SUS. These results suggest that the expression of ANP shows an increase in atrial and left ventricular myocardium of 4-week tail-suspended rats. Enhanced expression of VAMP-1/2 associated with ANP vesicles confirms the increased expression of ANP in atrial and left ventricular myocardium.

The association between polymorphism of transforming growth factor-β1 and radiochemotherapy response and survival in esophageal squamous cell carcinoma patients / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluate the association between polymorphism of transforming growth factor-β1 (TGF-β1)-509C/T and radiochemotherapy response and survival in esophageal squamous cell carcinoma (ESCC) patients.</p><p><b>METHODS</b>The genotype of TGF-β1-509C/T was detected by polymerase chain reaction-based restriction fragment length polymorphism assay (PCR-RFLP) in 230 ESCC patients receiving radiotherapy alone or in combination with chemotherapy. Unconditional multivariate logistic regression analysis was done to estimate adjusted odds ratios (ORs) along with the corresponding 95% confidence intervals (CIs) for the polymorphism and radiochemotherapy response. The associations between overall survival time or hazard ratio (HR) of ESCC patients and genetic variation or the clinical data were estimated by applying univariate and multivariate Cox-regression analyses.</p><p><b>RESULTS</b>Among 208 patients with upper gastrointestinal contrast assessment, 87 cases were susceptible to radiochemotherapy treatment and the TGF-β1-509CC, CT and TT genotype patients were 17 (19.5%), 48 (55.2%) and 22 (25.3%), respectively. Among the patients who were insensitive to radiochemotherapy treatment (n = 121), the TGF-β1-509CC, CT and TT genotype patients were 39 (32.2%), 54 (44.6%) and 28 (23.2%), respectively. Compared with TGF-β1-509CC genotype, the CT and TT genotype carriers had a significantly better treatment response (adjusted OR = 2.07, 95%CI, 1.05 - 4.09, P = 0.036). The median survival time of CC genotype patients was 17.0 (95%CI, 12.0 - 23.0) months, CT genotype patients was 22.0 (95%CI, 16.0 - 33.0) months and TT genotype patients was 25.0 (95%CI, 15.0 - 41.0) months. Compared to CC genotype patients, the survival time difference of CT and TT group was close to the statistical break point (P = 0.063). Our data showed that the subjects with CT or TT genotype had an decreased HR respectively as compared with those with CC genotype (CT, adjusted HR = 0.81, 95%CI, 0.52 - 1.24; TT, adjusted HR = 0.86, 95%CI, 0.65 - 1.12), but the difference was not statistically significant (P > 0.05). However, tumor location, clinical stage and radiochemotherapy response affected the overall survival time of the patient significantly (adjusted HR = 1.28, 95%CI: 1.01 - 1.61, P = 0.040; 1.49, 95%CI, 1.17 - 1.88, P = 0.001; 1.55, 95%CI, 1.06 - 2.26, P = 0.023, respectively).</p><p><b>CONCLUSION</b>These results suggest that TGF-β1-509C/T polymorphisms were associated with radiochemotherapy for esophageal squamous cell carcinoma which might be genetic markers for prediction of the radiochemotherapy response in ESCC patients.</p>

Brain metastasis treated with Cyberknife / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cyberknife can greatly raise the fractional dose of stereotactic radiosurgery, thus improving its clinical efficacy. We retrospectively analyzed clinical outcomes of brain metastasis treated with Cyberknife.</p><p><b>METHODS</b>We analyzed 40 cases of brain metastases treated with Cyberknife in the Tianjin Cancer Hospital from August 1, 2006 to August 1, 2007, for a total of 68 lesions with maximal diameter of 0.4 - 7.5 cm (average 1.88 cm). Total hypofractional radiated dosage was 18 - 36 Gy (5 - 25 Gy/F, 1 - 5 F) by Cyberknife. We evaluated the remission rate of clinical symptoms, correlation factors to new foci, 3-month local control rates, and 3-month and 1-year survival rates. All patients were followed up for more than 14 months.</p><p><b>RESULTS</b>After 1 week, clinical remission was 90.0% (36/40). After 3 months, the local control rate and therapeutic effective rate were 77.9% (53/68) and 94.1% (64/68), respectively, as observed by cranium augmentation CT or MRI. The three-month, six-month and 1-year survival rates were 97.5% (39/40), 82.5% (33/40) and 67.5% (27/40), respectively. Fourteen patients had neopathy outside the original lesion after 3 months. Neopathy was not correlated with age, whole-brain radiotherapy, number of original lesions, maximum diameter of the original lesion, therapeutic dose per fraction, therapeutic frequency or total therapeutic dose.</p><p><b>CONCLUSIONS</b>Cyberknife got perfect clinical outcomes by higher dosage per fraction. It is an appropriate and valid treatment shortcut for brain metastasis.</p>

Practice and Exploration of the Teaching Methods of Self-designed Experiment in Pathophysiology / 中华医学教育探索杂志

The self-designed experimental teaching method is introduced in detail in this paper,including the preparative work before class,discussion of experimental designing proposal,and accomplishment of specific experiment and so on.The teaching method innovations on pathophysiology experiment are very helpful to cultivate the students' ability to solve practical problem and lay the foundation to cultivate talented medical science personal.

Application of Case Discussion in Pathophysiological Teaching / 中华医学教育探索杂志

Case discussion is an effective approach,which combines basic theory with clinical medicine.It can evoke students' interest and cultivate their creative thinking capacity.Moreover,it can improve teachers' general ability in teaching pathophysiolo- gy.In this article,we discuss the application of case discussion in pathophysiology teaching.

Analysis of lecithin-cholesterol acyltransferase cDNA and protein sequence from tree shrew / 中国医学科学院学报

<p><b>OBJECTIVE</b>To acquire cDNA sequence of lecithin-cholesterol acyltransferase (LCAT) from tree shrew and analyze the sequence structure.</p><p><b>METHODS</b>The first strand cDNA was acquired by reverse transcription using mRNA from tree shrew liver as template. By the method of SMART RACE PCR, tree shrew LCAT cDNA was acquired and deduced its amino acids sequence. The sequence and structure of tree shrew LCAT cDNA and amino acid were analyzed and predicted by the molecular software.</p><p><b>RESULTS</b>Tree shrew LCAT cDNA is composed of 1,340 bp, including 2 bp 5' untranslated region (5' UTR), 1,320 bp open reading frame (ORF) which encodes protein precursor of 440 amino acids (24 amino acids signal peptide and 416 amino acids mature peptide), and 18 bp 3' untranslated region (3'UTR). The stop codon is TAA and there is a poly (A) signal sequence AATAAA and a 25 bp poly (A) tail. Tree shrew LCAT cDNA sequence has been accepted by GenBank as a new gene, accession number AF272861 and its homology with human and baboon was 90% and 89%, respectively.</p><p><b>CONCLUSION</b>The sequence of LCAT cDNA in tree shrew has high identity with that of human and other experimental animal species.</p>