OBJECTIVETo investigate the effects of metoprolol on electrophysiology of ischemic and anoxic myocardium in diabetic rats.

METHODSForty Sprague-Dawley (SD) rats were divided into 4 groups: diabetes group; diabetes and ablation of left sympathetic nerve group; diabetes and metoprolol group and sham group. The diabetes model was induced by intraperitoneal injection of streptozotocin (STZ, 60 mg/kg). The ventricular diastolic effective threshold (DET), effective refractive period (ERP), and Ventricular fibrillation threshold (VFT) were measured. The serum concentration of nerve growth factor (NGF) was measured.

RESULTSMetoprolol increased DET of ischemic and anoxic myocardium in diabetic rats. The ablation of the left sympathetic nerve increased VFT of diabetic rats. VFT in metoprolo group was significantly increased compared to diabetes group after ischemia. The concentrations of NGF in diabetic group and metoprolol group were higher than those in sham group. There were no difference in NGF levels between ablation of left sympathetic nerve group and sham group.

CONCLUSIONThe remodeling of sympathetic nerve affects the electrophysiology of ischemic myocardium of diabetic rats. Metoprolol can increase the VFT and decrease the excitation threshold of the ischemic myocardium in diabetic rats.

Animals ; Diabetes Mellitus, Experimental ; physiopathology ; Heart ; drug effects ; physiopathology ; Male ; Metoprolol ; pharmacology ; Myocardial Ischemia ; physiopathology ; Nerve Growth Factor ; blood ; Rats ; Rats, Sprague-Dawley ; Sympathectomy

OBJECTIVETo study the cytotoxicity induced by chrysotile asbestos (CA), rock wool (RW) and wollastonite (WS).

METHODSV79 cells were divided into 4 groups. i.e. CA group, WS group, RW group and control group (200 microl PBS). The exposure concentration of dusts was 100 mg/L, The cell viability was detected by MTT and lactate dehydrogenase (LDH) activity assays. The technique of scanning electron microscopy was used to examine the change of V79 cells.

RESULTSSiO2 was main constituent for 3 kinds of dusts. In MTT assay, the cell viability of RW and WS groups was 64.8% and 65.7%, respectively, which were significantly higher than that (54.5%) of CA group (P < 0.01). In LDH assay, the LDH activity of RW and WS groups [(15.7 +/- 50.9), (12.3 +/- 3.7) U/L, respectively] was significantly lower than that [(20.2 +/- 0.9) U/L] of CA group (P < 0.05). In scanning electron microscopy examination, it was found that the two ends of V79 cells in CA group contained a great deal of fibers remaining bodies, but the V79 cell appearance in RW and WS groups was normal.

CONCLUSIONThe cytotoxicity induced by RW and WS is significantly lower than that induced by CA for V79 cell.

Animals ; Asbestos, Serpentine ; toxicity ; Calcium Compounds ; toxicity ; Cell Line ; drug effects ; Cricetinae ; Cytotoxins ; toxicity ; Lactate Dehydrogenases ; metabolism ; Mineral Fibers ; toxicity ; Silicates ; toxicity

Objective To observe protective effects on rat serum cardiac enzymes and the antioxidant capacity of selenium and vitamin E.Methods According to body weight and 2 × 2 factorial design,eighty male Wistas rats were randomly divided into four groups:low selenium and low vitamin E group(feed containing 23.42％ of the low selenium yeast,excluding vitamin E),low selenium and adequate vitamin E group (feed containing 23.42％ of the low selenium yeast and vitamin E 160 mg/kg),adequate selenium and low vitamin E group(feed containing 46.84％ of the low selenium yeast and sodium seleni 0.25 mg/L in water,excluding vitamin E),adequate selenium and adequate vitamin E group(feed containing 46.84％ of the low selenium yeast,vitamin E 160 mg/kg and sodium selenite 0.25 mg/L in water),20 rats every group.Rats were feed with synthetic feed,and given intraperitoneal anesthesia after 26 weeks of feeding.Blood was collected to observe the impact of selenium and vitamin E on rat cardiac enzymes and myocardial antioxidant capacity and their interactions.Serum creatine kinase (CK) was measured using the continuous monitoring method,creatine kinase isozymes (CK-MB) and lactate dehydrogenase(LDH ) using the immune suppression method,the whole blood GSH-Px assay using the dithiobis nitrohenzoic acid(DTNB) method,serum superoxide dismutase(SOD) using the xanthine oxidase method,total antioxidant capacity (T-AOC) using the complex colorimetry method,the content of propylene glycol (MDA) using the thiobarbituric acid colorimetric method,and reactive oxygen species(ROS) using the colorimetric method.Results Group differences of serum CK,CK-MB,LDH,whole blood GSH-Px activity,serum T-AOC vitality,MDA and ROS content were statistically significant(F=9.797,17.041,48.399,3.744,224.900,49.384,5.045,all P＜ 0.05).Compared with the two low selenium groups and one adequate selenium group,the vitalities of CK,CK-MB,LDH and the contents of MDA[(1577.75 ± 451.87),(1239.15 ± 344.99),(884.25 ± 133.84)U/L,(5.688 ±1.169) × 103 nmol/L; (1474.21 ± 398.38),(1014.84 ± 215.40),(523.00 ± 98.05)U/L,(4.035 ± 0.487 ) × 103 nmol/L and (1180.10 ± 245.51),(948.75 ± 173.68),(676.70 ± 193.63)U/L,(3.406 ± 0.146) × 103 nmol/L]increased significantly in adequate selenium and adequate vitamin E group[( 1056.80 ± 250.98),(721.70 ±129.98),(404.65 ± 72.49)U/L,(3.010 ± 1.270) × 103 nmol/L,all P ＜ 0.05) ].The activity of GSH-Px was obviously increased in the two adequate selenium groups[ (96.611 ± 8.238) × 103,(103.024 ± 8.217) × 103 U/L,all P ＜ 0.05],compared with the two low selenium groups[ (60.356 ± 8.179) × 103,(63.117 ± 8.281) × 103 U/L].Selenium affected the activities of CK,CK-MB and LDH(F =27.09,31.58,29.66,all P＜ 0.01 ),and vitamin E affected the activities of CK-MB and LDH(F=18.9,11.2.all P＜ 0.01 ),but both selenium and vitamin E had no interactions on the activities of CK,CK-MB and LDH (F=0.02,0.001,2.22,all P＞0.05).Selenium affected the activity of GSH-Px and the content of MDA(F=6.74,95.68,all P＜ 0.05),vitamin E affected the activity of T-AOC,the contents of MDA and ROS(F=6.42,36.73,8.43,all P＜0.05),but selenium and vitamin E had interactions only on the content of MDA(F =13.82,P＜ 0.05).Conclusions Long-term selenium or vitamin E deficiency,can reduce the body's antioxidant capacity,leading to the occurrence of myocardial injury.Selenium and vitamin E can improve the body's oxidation capacity,playing a role in myocardial protection.

ObjectiveTo explore the effect of selenium,protein and vitamin E deficiency on mRNA expression of rat cardiac selenoprotein,and their relation with myocardial injury.MethodsForty male Wistar rats were randomly divided into 4 groups:low selenium low protein low vitamin E group(group A),low selenium low protein adequate vitamin E group(group B),adequate selenium adequate protein low vitamin E group(group C),and adequate selenium adequate protein adequate vitamin E group (group D),10 rats in each group.The activity of whole blood glùtathione peroxidase(GSH-Px ) was measured using dithiobis nitrobenzoic acid (DTNB) at the end of sixth month experiment.The levels of mRNA expression of glutathione peroxidase 1(Gpx1),phospholipid hydroperoxide glutathione peroxidase 4(Gpx4),thioredoxin reductase(TrxR),selenoprotein P(Se-P) and selenoprotein W(Se-W) were determined by real-time fluorescence quantitative PCR at the end of sixth month.Histopathological changes of myocardial injury were observed with light microscope.ResultsThe activity of GSH-Px was (44.6 ± 3.1 ),(45.5 ± 1.6),(86.6 ± 2.2),(85.6 ± 1.2)U/L,respectively,in the above four groups at the end of sixth month,and the difference was statistically significant(F =100.7,P ＜ 0.01 ) ; the activity of GSH-Px of groups C and D was higher than that of groups A,B(all P ＜ 0.05).mRNA expression of myocardial tissue of the four groups was as follows,Gpx1(0.099 ± 0.312,0.054 ± 0.007,0.386 ± 0.067,0.340 ± 0.085),Gpx4(1.005 ± 0.089,0.810 ± 0.229,0.895 ± 0.084,0.922 ± 0.399),and Se-W(0.188 ± 0.080,0.119 ± 0.069,0.574 ± 0.167,0.570 ± 0.383),and the difference was statistically significant(F =112.1,3.76,22.8,all P ＜ 0.05) ; the mRNA levels of Gpx1,Se-W of groups C,D were significantly higher than that of groups A,B(all P ＜ 0.05).The mRNA expression of Gpx4 of group A was higher than that of group C(P ＜ 0.05).The mRNA expression of TrxR(0.130 ± 0.037,0.127 ± 0.038,0.134 ± 0.021,0.120 ± 0.014) and Se-P(0.446 ± 0.155,0.413 ± 0.152,0.385 ± 0.041,0.408 ±0.208 ) was not statistically different among the four groups (F =0.91,1.75,all P ＞ 0.05).Pathological changes of myocardial tissue were mainly as foci of coagulative necrosis.The necrosis detection rate of the four groups was 8/10,4/9,2/10,and 1/10,respectively,and the difference was significant statistically(Fisher exact test,P =0.0067).ConclusionsLong-term selenium,protein and vitamin E deficiency will reduce body antioxidant capacity and lead to myocardial injury.The mRNA levels of Gpx1 and Se-W and selenium level are closely related.The mRNA levels of Gpx4,TrxR and Se-P remain relatively stable.

OBJECTIVETo investigate the protective effect of manganese superoxide dismutase (MnSOD) gene transfer to small intestinal epithelial cells from radiation injury.

METHODSHerpes simplex virus (HSV) vector containing both the human MnSOD and GFP genes was introduced into mouse small intestine. Expression of MnSOD by the intestinal villi was confirmed by nested RT-PCR, immunofluorescence and enzyme activity assay. Mice were then given various doses of irradiation over the abdomen. The height of intestinal villi was measured on histopathology sections by SZ-PT optical system before irradiation, 24 h and 72 h post-irradiation. All comparisons were performed by one-way analysis of variance using the SPSS statistical software to analyze the significance between groups.

RESULTSNested RT-PCR, immunofluorescence and enzyme activity assay of MnSOD demonstrated overexpression and increased activity of MnSOD in the inoculated intestine of mice. Control (sham inoculated) irradiated mice showed decreased villi height by 40.1%-59.3% on day 1 and 44.2%-65.1% on day 3 (7.5-15 Gy). Treatment of mice with HSV-MnSOD prior to radiation led to statistically significant radioprotection of the small bowel with mean villi height decreased by only 3.1%-12.4% on day 1 and 6.3%-29.1% on day 3.

CONCLUSIONThe results demonstrate that overexpression of human MnSOD via a replication defective herpes simplex viral vector is an effective method to protect the small intestine from damage caused by ionizing radiation.

Animals ; Epithelial Cells ; metabolism ; Genetic Therapy ; Genetic Vectors ; Intestine, Small ; metabolism ; Mice ; Radiation Injuries, Experimental ; prevention & control ; Simplexvirus ; genetics ; Superoxide Dismutase ; genetics ; Transfection

Objective：The aim of this study was to evaluate radiation induced temporomandibular joint damage in the patients with nasopharyngeal carcinoma, and its correlative factors were analyzed. Methods： From November 7, 1966 to July 2, 1999, 352 patients with nasopharyngeal carcinoma received radical conventional radiotherapy were eligible for this analysis. The total dose of the temporomandibular joint were 51.90－ 78.89 gray and the overall treatment time were 35－ 141 days. The endpoint was the distance between two dens incisivus medialis (DDIM). The relationship between total doses and temporomandibular joint lesion was illustrated with curve estimation. Multivariate analysis with Logistic Regress was performed to evaluate the significance of prognostic variables on temporomandibular joint lesion. Results： The patient of DDIM60.00－ 70.00 gray, and >70.00－ 78.89 gray were 46.4％ , 53.5％ , and 62.3％ , respectively (P=0.050); and in the patients who insisted in opening mouths practice or not were 51.6％ and 61.7％ respectively (P=0.028); and in patients at age of 18－ 42 and 43－ 71 were 54.1％ and 62.7％ respectively(P=0.040). They were all significant prognostic factors for radiation induced temporomandibular joint lesion. Conclusion： Radiation induced temporomandibular joint lesion in radiation treated NPC patients was serious. The total dose of temporomandibular joint, opening mouths practice and age are three significant prognostic factors.

OBJECTIVETo analyze the clinical outcome of 934 primary nasopharyngeal carcinoma treated with conventional external beam radiotherapy alone.

METHODS34 patients were treated from Jan. 1, 1999 to Dec. 31, 1999. The radiation fields were delineated according to the CT/MRI imaging findings on disease extent. Two lateral opposing isocentric portals with customized blockings were used for the nasopharynx and upper neck. The dose delivered to tumor in the nasopharynx was 68-70 Gy/2 Gy fraction/7 weeks. The doses delivered to the neck was 60-70 Gy/6-7 weeks for patients with positive lymph nodes and 50 Gy/5 weeks for the patients with negative lymph node.

RESULTSThe 1-, 2-, 3- and 4-year overall survival rate (OS) was 89.5%, 81.9%, 78.1% and 75.7%, and metastasis-free survival rate (MFS) was 84.0%, 77.2%, 74.4% and 72.0%, respectively. The 1-, 2-, 3- and 4-year disease-free survival rate (DFS) was 80.8%, 73.1%, 68.5% and 65.1%, and the relapse-free survival rate (RFS) was 95.5%, 92.7%, 90.3% and 87.3%, respectively. The overall failure rate was 30.9% (289/934). At the end of the radiotherapeutic course, the percentage of residual disease was 14.6%. The 4-year loco-regional recurrence and distant metastasis rates after radiotherapy were 7.2% and 9.2% with a median time of 19.3 months and 12.8 months.

CONCLUSIONIt may be helpful to improve radiotherapy curative effect when the target is individually designed through improving irradiation technique according to CT/MRI findings and by shortening the overall course time, enhancing irradiation dose and strictly implementing QA/QC measures.

Adolescent ; Adult ; Aged ; Carcinoma, Squamous Cell ; diagnostic imaging ; radiotherapy ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Nasopharyngeal Neoplasms ; diagnostic imaging ; radiotherapy ; Radiotherapy Dosage ; Retrospective Studies ; Survival Analysis ; Tomography, X-Ray Computed ; Treatment Outcome

Objective To dynamically analyze the evolutionary process of cerebral edema absorption and the level of local iron in rats with intra-cerebral hematoma by high-field strength 7 Tesla MRI and explore the characteristics and mechanism of secondary injury after intra-cerebral hematoma.Methods Sixteen adult SD rats (about 150 g) were randomly divided into experimental group (n=10) and control group (n=6).Rat models in the experimental group were established by performing injection of 50 μL their own venous blood into their right caudate nucleus accurately. Rats in the control group were used normal saline,instead.After that,head MRI (T2 and T2-star scans) was performed 1,2,3,7 and 14 d after the injection; their imaging features were compared. Results Nine rats in the experimental group survived and 1 died after the operation; in the early days (within 3 d), the T2 weighing imaging showed that the time of relaxation surrounding the hematoma was longer than that in control group,suggesting that the zone of the edema surrounding the hematoma became more clearly.In the early days (within 3 d),T2-weighted imaging was clear,and the time of relaxation surrounding the hematoma increased rapidly,steadily improved 3 d after the operation and reached its peak level 7 dafter the operation; the damage area absorption decreased steadily but turned widening 3 d later and reached the peak 7 d later.T2-star value reached the peak rapidly 3 d after the operation,and then,moderated the downturn.The rats in the control group showed no obvious signal changes under MRI,except those with needle tract injury. Conclusion Secondary injury after intra-cerebral hemorrhage shows a rapidly injury progress in the short terrn at first,and then,has intensify again after a stable period; the local iron diffusion trend is synchronized to the secondary injury,suggesting that iron may play a key role in the mechanism of secondary brain edema.

OBJECTIVES: To detect the genotype of ABO blood group by SNaPshot technology. METHODS: DNA were extracted from the peripheral blood samples with known blood groups （obtained by serology） of 107 unrelated individuals in Yunnan. Six SNP loci of the 261th, 297th, 681th, 703th, 802th, and 803th nucleotide positions were detected by SNaPshot Multiplex kit, and relevant genetics parameters were calculated. RESULTS: In 107 blood samples, the allele frequencies of types A, B, O^A, and O^G were 0.355 1, 0.168 2, 0.230 0 and 0.247 6, respectively, while that of types A^G and cis AB were not detected. The genotyping results of ABO blood group were consistent with that of serologic testing. CONCLUSIONS SNaPshot technology can be adapted for genotyping of ABO blood group.
ABO Blood-Group System/genetics* ; Alleles ; Asian People/genetics* ; China ; DNA ; Ethnicity ; Gene Frequency ; Genotype ; Humans ; Polymerase Chain Reaction/methods* ; Polymorphism, Restriction Fragment Length

Objective The aim of this study was to demonstrate the immunogenicity and safety of diphtheria, tetanus, pertussis (acellular, component) , poliomyelitis (inactivated) vaccine (adsorbed) and Haemophilus influenzae type b conjugate vaccine (DTaP-IPV//PRP-T) combined vaccine compared with commercially available DTaP (diphtheria, tetanus and pertussis), Haemophilus influenzae type b (Hib), tetanus conjugate and IPV monovalent vaccine. Methods Subjects were randomly divided into three groups, Group A and Group B were DTaP-IPV//PRP-T combined vaccine (PENTAXIMTM) vaccinated at 2,3,4 months of age or 3,4, 5 months of age respectively; Group C was commercially available DTaP. Hib tetanus conjugate (Act-HIBTM) and IPV (IMOVAX PolioTM) vaccines vaccinated at 3,4, 5 months of age. All groups received booster dose at 18 to 20 months of age, with antibody titers tested. Non-inferiority analysis was demonstrated in terms of seroprotection / seroconversion rates between Group A, Group B respectively and Group C. Safety information was collected after each vaccination to assess the safety of investigational vaccines. Results The non-inferiority of DTaP-IPV//PRP-T combined vaccine vaccinated at 2,3,4 or 3,4, 5 months of age versus DTaP, Hib tetanus conjugate and IPV vaccine was demonstrated for all vaccine antigens in both primary and booster phases in terms of seroprotection/seroconversion rates. DTaP-IPV//PRP-T combined vaccine was well tolerated. The rate of solicited/unsoliciated severe adverse reactions was very low and similar to the control vaccines. Conclusion DTaP-IPV//PRP-T combined vaccine was highly immunogenic with good safety profile in Chinese infants, which was comparable to the commercially available control vaccines.