Objective To investigate the occurrence of p16 gene methylation in the population chronically exposed to arsenic in Inner Mongolia,and to study the molecular mechanisms of carcinogenesis associated with arsenic exposure.Methods The study group was composed of 40 cases of typical arseniasis selected from the epidemic area,and the two control groups consisting respectively of 40 non-arseniasis cases selected from the same epidemic area,and 40 healthy persons enrolled from non-epidemic area.Methylation of p16 gene in the blood specimens were analyzed for all the subjects with MS-PCR techniques,and statistical analysis was performed using chi square test.Results The positive rates of p16 hypermethylation in blood specimens were 65.0%,47.5% and 20.0% respectively in study group and two control groups,and the rate of hypermethylation increased with the increase in arsenic exposure with drinking water in epidemic areas.The positive rate of p16 hypermethylation showed significant differences(P

Objective To investigate the effect of rosiglitazone (ROS),a peroxisome poliferator- activated receptor (PPAR)?ligand,combined with all-trans retinoic acid (ATRA) on anti-angiogenesis of transplanted gastric cancer in nude mice,and to explore the mechanism of anti-angiogenesis prelimina- rily.Methods The model of xenograft tumor in nude mice were established by inoculating human gastric cancer cells line MGC803 (lower differentiated) into the back of nude mice subcutaneously.The cancer- bearing nude mice were divided randomly into 5 groups:group 1 (n=6) with no treatment;ROS treat- ment (group 2,n=6),ROS combined ATRA treatment including:low dose treatment (group 3,n= 6),moderate dose treatment (group 4,n=6) and high dose treatment (group 5,n=6).After treated for forty days,the volume change of tumor and tumor inhibition rates were observed.The expression of CD34,vascular endothelial growth factor (VEGF) in grafts were detected by immunohistochemical and calculated the difference of MVD.The mRNA expression levels of VEGF,HIF-l?were detected by RT- PCR assay accordingly.Results①The volume of tumor was significantly decreased in ROS treatment group compared with group 1 (P＜0.01).The tumor inhibition rates of group 2 were similar to group 3 (P＞0.05).With the increasing of the dose of ROS the tumor inhibition rates were increased.They were dose-dependent in specified dose-range.②ROS could inhibit angiogenesis of xenograft tumor and depress expression of mRNA of VEGF and HIF-l?.When ROS combined with ATRA,the increasing of dose of ROS,inhibiting angiogenesis of tumor and depressing expression of mRNA of VEGF and HIF-l?were found (P＜0.05).Conclusion ROS (25 mg?kg?2 d~(-1)) can inhibit the growth of tumor,and ROS combined with ATRA can further inhibit the growth of tumor,which may be through the path of PTEN by inhibiting the angiogenesis of tumor

The author introduces the basic concepts of microsatellite and population genetics and its characteristics, expounds the application of these theories for population genetic structure and genetic diversity, gene flow and evolutionary significant unit ESU division research. This paper discuss its applicationin study of genetic causes, origin of cultivation, different regional origins of geoherbs, aiming at providing a new theory and method for geoherbs.
Drugs, Chinese Herbal ; Evolution, Molecular ; Genetic Markers ; genetics ; Genetic Techniques ; Geography ; Microsatellite Repeats ; genetics

OBJECTIVETo explore the expression of p-p38 MAPK protein and the number of astrocytes expressing p-p38 MAPK in CA1 hippocampus in rats during the induction of brain ischemic tolerance induced by intermittent hypobaric hypoxia (IH) preconditioning.

METHODSThirty healthy adult male Wistar rats were randomly divided into 6 groups (n = 5 in each group): sham 0 min group, IH + sham 0 min group, sham 7 d group, IH + sham 7 d group, Ischemia (Is) 7 d group, and IH + Is 7 d group. Neuropathological evaluation was performed by thionine staining in CA1 hippocampus in rats. The expression of p-p38 MAPK in CA1 hippocampus was observed by immunohistochemical staining. And the number of astrocytes expressing p-p38 MAPK was observed by immunofluorescent double labeling.

RESULTSThe results showed that IH preconditioning induced brain ischemic tolerance successfully. At the same time, IH preconditioning obviously up-regulated the expression of p-p38 MAPK protein in CA1 hippocampus, and also increased the number of astrocytes expressing p-p38 MAPK.

CONCLUSIONIt might be concluded that IH preconditioning induced brain ischemic tolerance by up-regulating the expression of p-p38 MAPK protein in pyramidal neurones and astrocytes.

Animals ; Astrocytes ; enzymology ; pathology ; Brain Ischemia ; enzymology ; pathology ; Disease Models, Animal ; Hippocampus ; enzymology ; Hypoxia ; Ischemic Preconditioning ; methods ; Male ; Phosphorylation ; Pressure ; Rats ; Rats, Wistar ; p38 Mitogen-Activated Protein Kinases ; metabolism

Adult ; Bone Neoplasms ; Ear Canal ; Ear Neoplasms ; Female ; Humans ; Osteochondroma

ObjectiveTo observe the effects of mild hypothermia on post-resuscitation myocardial dysfunction in rabbits in order to elucidate the underlying mechanism of hypothermia.Methods After setting up rabbit model of cardiopulmonary resuscitation,20 rabbits were randomly ( random number)divided into two groups,namely normothermic resuscitation group (group A,n =10 ) and post-ROSC hypothermia group ( group B,n =10).In the group A,animals wore treated with standard CPR after cardiac arrest.In post-ROSC hypothermia group,the body temperature of animals was cooled to 32 ～ 34°C after successful ROSC.The left ventricular end-diastolic pressure (LVEDP),left ventricular pressure rise and fall rates ( ± dp/dtmax,serum concentrations of heart-type fatty acid-binding protein (H-FABP) and 8-isoprostaglandin F2a (8-iso-PGF2a) and Cyclooxygenase-2 (COX-2) were observed. Results Compared with the A group,the B group had significantly better hemodynamics,and lower serum H-FABP,8-isoPGF2a and COX-2 levels in the early stage of post-resuscitation ( both P ＜ 0.05 ).ConclusionsMild hypothermia attenuated post-resuscitation myocardial dysfunction during the early period of postresuscitation.The cryoprotective effect on myooardium is likely associated with the reduction of 8-iso-PGF2a and COX-2.

Objective To explore the imaging features of bone marrow edema(BME)and soft tissue edema(STE)caused by bone tumors and tumor-like lesions.Methods Ninety nine patients with bone tumors and tumor-like lesions which were proved by surgical pathology were reviewed.The patients were divided into benign and malignant groups.Evaluation parameters included the size and signal intensity of BME and STE,the features of enhancement,the bone sclerosis and its relation with BME,and joint effusion,et al.The data of two groups were analyzed by X2 test.Results There were 40 patients in benign group and 59 patients belonged to malignant group.BME and STE demonstrated low signal on T1-weighted images and high signal on fat-suppressed T2-weighted images.Some BMEs demonstrated low signal on T2weighted images,which corresponded to sclerosis on X-ray film and(or)CT.Both BME and STE demonstrated uniform enhancement.There were statistically significant differences between benign and malignant groups including the frequency of BME.sclerosis.the median of the size of the BME and STE (P<0.05),which were 57.5%(23/40),25.0%(10/40),2.7 cm,1.3 cm,and 32.2%(19/59).3.4%(2/59),1.6 cm,1.7 cm respectively.No significant differences between the frequency of STE,joint effusion in 2 groups(P>0.05).Conclusions Both benign bone tumors and tumor-like lesions and malignant bone tumors can be accompanied by BME and STE.The size of BME in the benign bone tumors and tumor-like lesions is bigger than those in malignant ones,and the size of STE in malignant bone tumors is bigger than benign ones.

Objective To evaluate the effect of propofol on noise-induced hearing loss in guinea pigs.Methods Forty-eight healthy adult male guinea pigs,aged 3 months,weighing 400-500 g,were randomly divided into 4 groups (n =12 each) using a random number table:control grotup (C group),propofol group (P group),noise-induced hearing loss group (N group),and propofol + noise-induced hearing loss group (P + N group).A loading dose of propofol 5 mg/kg was infused intravenously over 5 min,followed by infusion at 20 mg· kg-1 · h-1 for 115 min in P and P + N groups,while the equal volume of normal saline was given in N group.N and P+ N groups were exposed to the noise of 4 kHz center frequency and 118-122 dB sound pressure level for 120 min.Distortion product otoacoustic emission (DPOAE) was measured before noise exposure (T1) and at 1 h after the end of noise exposure (T2) and the amplitudes were recorded at the frequencies of 2,4,6 and 8 kHz.After the second measurement of DPOAE,all the animals were sacrificed and organs of Corti were harvested for determination of cochlear 8-isoprostaglandin F(2alpha) (8-iso-PGF2α) content (by ELISA assay) and out hair cell (OHC) count.The rate of OHC lesions was calculated.Results The DPOAE amplitude was significantly lower at frequencies of 4,6 and 8 kHz at T2 than at T1 in N and P + N groups (P ＜ 0.05).Compared with C group,the DPOAE amplitude was significantly decreased at frequencies of 4,6 and 8 kHz at T2,while the cochlear 8-isoPGF2α content and rate of OHC lesions were increased in N and P + N groups (P ＜ 0.05).Compared with N group,the DPOAE amplitude was significantly increased at frequencies of 4,6 and 8 kHz at T2,while the cochlear 8-iso-PGF2α content and rate of OHC lesion were decreased in P + N group (P ＜ 0.05).Conclusion Propofol can reduce noise-induced hearing loss in guinea pigs possibility through decreasing oxidative stress response-induced damage to cochlear OHCs.

Objective To explore the clinical diagnosis and treatment of cyclic vomiting syndrome in children.Methods Thirty children proved with cyclic vomiting syndrome admitted from January,1998 to January,2003 were analyzed retrospectively.Results Cyclic vomiting syndrome was most likely to occur in 3-12 years old.The male to female ratio was 3∶2.The clinical manifestations were recurrent vomiting.Twenty-one cases had inducements,while 9 cases had not inducements.It was safe and efficient that curing cyclic vomiting syndrome with cyprohetadine and amitriptyline.Conclusions If these children with cyclic vomiting syndrome are inefficient to treatment,excluding metabolizable diseases,gastrointestinal,neurological diseases,they may be diagnosed cyclic vomiting syndrome,and cured with cyprohetadine and amitriptyline.

Objective To observe the effect and security of lovasatin treating hyperlipidemia in children with steroid resistance nephrotic syndrome(SRNS).Methods Thirty-seven children with SRNS were administered lovasatin with normal liver function before lipid-lowing treatment.The changes of plasma lipids [total cholesterol(TC),trigly ceride(TG)] and lipoprotins [low density lipoprotein(LDL),very low density lipoprotein(VLDL),high density lipoprotein(HDL)],albumin(Alb),serum creatinine(Scr),aminotransferase(ALT),24 hours of urinary protein and drug side-effects were observated for 4 weeks.All children treated with regular glucocorticoids therapy for 2 months still presented with urinary protein significant positive.Results There were decreasing of plasma lipids and lipoproteins after 2 weeks of lovasatin treatment,especially for TG,24 hours of urinary protein(Pa