Latest Issue
Volume 0 ， Issue 4 ， 2003
- Abstract：Objective.To study the change of taurine transport,and taurine transporter（TAUT）and cysteine sulfinate decarboxylase（CSD）mRNA contents in hypertension and hypertensive cardiomegaly.Methods.Taurine content was determined with a amino acid analyser.Taurine uptakes were deter-mined by（ 3 H）-taurine incubation.The content of TAUT and CSD mRNA levels were measured by com-petitive quantitative RT-PCR in myocardial and vascular tissues of L-N ω -nitro-arginine（L-NNA）-in-duced hypertensive rats.Results.After the treatment of rats with L-NNA for28days,myocardial and vascular taurine con-tents decreased by11%and15%（P<0.05）,respectively,and plasma taurine level increased by13%（P<0.05）.Myocardial and vascular Vmax of taurine uptake reduced by30%and19%（P<0.05）,respec-tively.Their Km of taurine uptake increased by36%and17%（P<0.05）.Myocardial and vascular TAUT mRNA content decreased by22%and19%（P<0.05）,respectively,but CSD mRNA content increased by22%（P<0.05）and30%（P<0.01）,respectively.Conclusions.This study suggests that there is a decreased taurine content in myocardial and vascu-lar tissues of L-NNA-induced hypertension rats.The decreased taurine content may result from the de-creased number of TAUT on the cell membrane mainly due to the down-regulation of TAUT gene and TAUT affinity caused by hypertension and hypertensive cardiomegaly.Keywords：L-N ω -nitro-arginine;taurine transporter;cysteine sulfinate decarboxylase6|14|0Updated：2024-04-10
- Abstract：Objective.To study the exact effects and characteristics of a constitutively active myosin light chain kinase fragment （MLCKF）on Ca 2+ -CaM dependent phosphorylation of myosin light chains（CDPM）of smooth muscle.Methods.Proteolysis of myosin light chain kinase（MLCK）by trypsin was used to obtain the con-stitutively active fragment of MLCK;Western blot was applied to demonstrate the homogeneity of typsin-digested MLCK fragments and intact MLCK.The phosphorylation of myosin light chains was detected us-ing SDS-PAGE and Scoin Image Software,and myosin Mg 2+ -ATPase activities were measured using spec-trophotometry to observe the characteristics of MLCKF in phosphorylating myosin light chains and stimu-lating myosin Mg 2+ -ATPase activities compared with intact MLCK.Results.Our assay demonstrated that MLCKF had a specific activity on CDPM.We also found that the extent of CDPM by MLCKF was greater than that by intact MLCK at different concentrations,differ-ent incubation time and different incubation temperatures.CDPM by MLCKF was also less influenced by the change of ionic strength of KCl than CDPM by intact MLCK.Mg 2+ -ATPase activities of phosphorylat-ed myosin light chains by MLCKF were higher than those by MLCK at different concentrations and dif-ferent reaction time.These differences were statistically significant （ P<0.01, P<0.05）.Conclusion.MLCKF not only possessed a specific activity on CDPM but also was more efficient than MLCK in phosphorylating myosin light chains and stimulating myosin Mg 2+ -ATPase activities.Our results suggested that MLCKF possibly plays a certain role in smooth muscle contraction-relaxation cycle.Keywords：proteolysis;MLCKF;phosphorylation;Mg 2+ -ATPase activity4|54|4Updated：2024-04-10
- Abstract：Objectives.To observe if lysophosphatidic acid（LPA）can influence nuclear nucleoside triphos-phatase（NTPase）activity of isolated hepatocyte from rat,and to investigate the possible mechanisms by which LPA affects the NTPase.Method.Isolated and cultured hepatocytes from rat liver were exposed to LPA（1×10 -9 ,1×10 -8 and5×10 -8 mol/L）with or without inhibitors of protein kinase C（PKC）and mitogen activating protein kinase kinase（MAPKK）,and the NTPase activity on nuclear envelope was assayed using ATP and GTP as substrate,respectively.Results.Nuclear NTPase activity of rat hepatocytes was potently stimulated by incubation of hepato-cytes with LPA in concentration?and time ?dependent manners.In hepatocytes incubated with LPA,nu-clear NTPase activity was significantly higher than that of the control（P<0.01）.In hepatocytes preincu-bated with PKC inhibitor H-7or MAPKK inhibitor PD98059,LPA-stimulated activation of nuclear NT-Pase was obviously attenuated.In addition,direct incubation of isolated hepatic nuclei with LPA had no effect on nuclear NTPase activity.Conclusion.LPA is involved in modulating nuclear NTPase activity in hepatocytes.The stimulating effect of LPA on the nuclear NTPase is mediated at least partly by PKC and MAPK-dependent pathway.Keywords：lysophoshatidic acid;nucleoside triphosphatase;hepatocyte4|15|0Updated：2024-04-10
- Abstract：Objective.To evaluate the clinical utility of a new non-invasive enzyme immunoassay（EIA）for the diagnosis of Helicobacter pylori（H.pylori）infection.Methods.Stool specimens of63patients were collected and tested by using a commercial kit for detecting Helicobacter pylori stool antigen（HpSA）,of which61patients also underwent 13 C-Urea breath test（ 13 C-UBT）.The tissue samples of31patients were obtained endoscopically and were examined with histologic technique（Warthin-Starry silver stain）.Regarded 13 C-UBT as a golden standard,HpSA test and histologic techniques were evaluated.Using this method,we also investigated the positive rate of H.pylori infection in children in Beijing.Results.The sensitivity and specificity of HpSA test were94.7%and95.1%respectively;the posi-tive and negative predictive values were97.3%and91.7%respectively;and the accuracy was95.1%.The results showed the prevalence of H.pylori infection was26.0%in children（3～18years）of district of Xicheng in Beijing.After treatment ,HpSA seems to disappear rapidly（3～5days）from the feces.Conclusion.The detection of HpSA in stool samples by HpSA test is a rapid noninvasive test for detecting H.pylori infection,and has both high sensitivity and high specificity.It is suitable for screening and diagnosis of H.pylori infection,monitoring the treatment efficacy in routine in all hospitals.Keywords：Helicobacter pylori;enzyme immunoassay4|10|0Updated：2024-04-10
- Abstract：Objective.To investigate the distribution frequency of parathyroid hormone（PTH）gene polymorphism in healthy adults from Bejing area and to explore the association of PTH genotypes with bone mineral density（BMD）.Methods.PTH gene polymorphism was detected in270subjects by polymerase chain reaction（PCR）and PCR /restriction fragment length polymorphism（PCR /RFLP）.The digestion products of restriction enzyme Bst B1were separated on1%agarose gels.PTH genotypes were confirmed by DNA sequences analysis.BMD was measured by dual-energy X-ray absorptiometry（DEXA,DPX -L ,Lunar）.Results.Genotype frequencies of BB,Bb,bb were73.7%,25.9%and0.4%respectively in Beijing adults（P<0.01）,67.1%,32.2%and0.7%in postmenopausal women,which was different from Japanese wom-en.We statistically compared bone mineral density at the lumbar2-4and proximal femur between BB and Bb genotypes.No obvious association was found between the BMD and PTH genotypes in Beijing women（P>0.05）.Conclusion.PTH gene polymorphism is not associated with BMD in Chinese women.The further research to explore the genetic risk factors of osteoporosis should be committed.Keywords：parathyroid hormone;gene polymorphism;bone mineral density4|14|1Updated：2024-04-10
- Abstract：Purpose.To evaluate the diagnosis and treatment of adrenal incidentalomas.Methods.One hundred and twenty-six patients with incidentalomas were analyzed,among them98underwent operation.Results.Eighty-eight of the adrenal incidentalomas were discovered by ultrasound.Of all the types of adrenal incidentalomas,52（41.3%）of them were adenomas;43（34.1%）were hypersecretory adrenal tumors,including29pheochromocytomas,9primary aldosteronisms ,1adrenogenitol syndrome combined with adrenal adenoma ,2Cushing’s syndrome combined with adenomas and2Cushing’s syndrome com-bined with nodular hyperplasias.All nonhypersecretory adrenal adenomas were under6cm,and all a-drenal carcinomas were above6cm.Conclusions.To search for hypersecretory adrenal tumors and to detect malignant adrenal tumors are quite essential in the process of diagnosing adrenal incidentalomas.For nonhypersecretory adrenal adeno-mas,the size of tumor is the most important index in determining whether the tumor is benign or malig-nant and whether the tumor needs to be treated with operation.Keywords：adrenal incidentaloma;diagnosis;treatment4|18|0Updated：2024-04-10
- Abstract：Objective.To identify a subset of breast cancer patients in whom metastatic disease is confined on-ly to the sentinel lymph node（SLN）.Methods.Sentinel lymph node biopsy is performed with the injecetion of Tc99m-SC,and a gamma probe.Sentinel node biopsy was compared with standard axillary dissection for its ability to reflect the fi-nal pathological status of the axillary nodes.The factors associated with non-SLN metastases were as-sessed in the univariate and multivariate analysis.Result.We successfully identified91out of95patients for SLN（95.8%）.The accuracy of sentinel lymph node to predict the axillary lymph node status was93.4%.Clinical tumor size and tumor grade were proved to be the independent predictive factors for non-SLN metastases by logistic regression model.Conclusion.In most cases,the gamma probe guided method is technically feasible for detecting sentinel nodes,accurately predicting the axillary lymph node status.A subset of the patients identified who have a low risk of non-SLN metastases may not require axillary lymph node dissection.Keywords：breast cancer;sentinel lymph node biopsy;non-sentinel lymph node4|25|0Updated：2024-04-10
- Abstract：Objective.To investigate PTEN expression and loss of heterozygosity（LOH）of its epigenetic microsatel-lites in gastric carcinoma and explore their roles in tumorigenesis and progression of gastric carcinoma.Methods.LOH of epigenetic microsatellites of PTEN（D10S541,D10S583and D10S1687）was exam-ined in advanced gastric carcinomas（n=56）by PCR-SSCP.The mRNA and protein expressions of PTEN gene were evaluated in normal mucosa（n=56）,early（n=11）and advanced carcinomas（n=56）of the stomach using RT?PCR and immunohistochemoistry respectively.PTEN mRNA and protein expressions were compared with clinicopathological staging and lymph node metastasis of tumors.The relationship be-tween PTEN mRNA expression and LOH of microsatellites was discussed,as well as relationship between PTEN mRNA and protein expression.Results.LOH of D10S541,D10S583and D10S1687was found in28.6%（16/56）of advanced gas-tric carcinomas.The positive rates of PTEN expression were80.4%（45/56）,45.5%（5/11）and32.1%（18/56）in normal gastric mucosa,early and advanced gastric carcinomas at mRNA level,while78.6%（44/56）,36.4%（4/11）and28.6%（16/56）at protein level.PTEN mRNA and protein were less fre-quently expressed in early and advanced gastric carcinomas than normal gastric mucosa（P<0.05）.There was negative correlation between PTEN mRNA expression and LOH of microsatellites（P<0.05）.PTEN protein expression paralleled to its mRNA expression（P<0.05）.The PTEN mRNA and protein expres-sions were negatively correlated with lymph node metastasis of advanced gastric carcinomas（P<0.05）.Conclusion.Down?regulated expression of PTEN and frequent LOH of its epigenetic microsatellites might play an important role in gastric carcinogenesis.Reduced PTEN mRNA expression was closely as-sociated with LOH of its epigenetic microsatellites.Altered expression of PTEN might contribute to lymph node metastasis of gastric carcinoma by decreasing cell adhesion and apoptosis,increasing angiogenesis and cell mobility.Keywords：PTEN gene;microsatellite instability;LOH;stomach neoplasms4|23|0Updated：2024-04-10
- Abstract：Object.To study the clinical manifestations,diagnostic methods,surgical management ,and prognosis of various neurogenic mediastinal tumors.Method.One hundred and ten cases of neurogenic tumors of mediastinum were reviewed and retro-spectively analyzed.Results.Operative or hospitalization death happened in2cases,complications occurred in8cases,mostly were Horner’s syndrome or recurrent nerve paralysis.During the follow?up,there were2recur-rences in102benign tumors,and4cases of neurofibrosarcoma or malignant neurilemmoma died within3years postoperatively.Conclusion.Most mediastinal neurogenic tumors are benign.It is enough to establish diagnosis by chest X?ray and CT scan.There are different features in the clinical manifestations,diagnosing methods,and surgical management for the dumbbell tumors.Minimal invasive surgery and video?assisted thora-coscopy surgery（VATS）have a special value in treatment of the selected neurogenic mediastinal tumors.Benign neurogenic tumors rarely recur after complete resection,whereas malignant neurogenic tumors have poor prognosis.Keywords：neurogenic mediastinal tumors;neurilemmoma;neurofibroma4|7|0Updated：2024-04-10
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- Abstract：Objective.In this study,we investigated the hypothesis that tumor necrosis factor（TNF）α-308gene polymorphism might be of the genetic predisposition to asthma and asthma phenotypes.Methods.TNFα-308gene polymorphism was genotyped in221random unrelated Northern Chinese population（comprising125asthmatics and96healthy controls）and52individuals from12asthmatic families with Han ethnic by using polymerase chain reaction（PCR）-restriction fragment length polymor-phism（RFLP）.Methacholine（Mch）broncho-challenge test,bronchial reversibility test and lung function were underwent in all asthmatics.Results.TNFα-3082homozygosity was present at a significantly higher frequency in asthmatics than that in controls（20.8%vs11.4%,P<0.05,OR2.259）,the TNF allele2was also higher in asthmatics compared with controls（0.42vs0.33,P<0.01）.TNFα-3082homozygosity was an weak independent risk factor for asthma etiology（OR0.226,P<0.05）.Moreover,patients carrying TNFα-3082homozy-gosity had less responsive to inhaledβ 2 -agonist in20minutes than patients carrying other two genotypes（24.1%vs29.5%vs38.8%,P<0.05）.Linkage analysis didn’t support that TNFαgene was linked to asthma （Likelihood of odds,LOD<1）based on familial data.Conclusion These results suggest that TNFα-3082homozygosity may be of a component contribut-ing to the genetic predisposition to asthma ,and airway responsiveness toβ2 -agonist.Keywords：tumor necrosis factor;asthma;genetic4|23|0Updated：2024-04-10
- Abstract：Objective.To introduce the properties of Chinese type A botulinum toxin（CBTXA,made by Lanzhou Institute of Biological Products）,and its long?term effect for focal dystonia and hemifacial spasm.Method.The purity and recovery of crude and crystalline toxin were tested.Long?term data from305patients with hemifacial spasm（HFS）,blepharospasm（BS）and cervical dystonia（CD）were evalu-ated and subgroups of patients received CBTXA injections between1994and2000in at least six sepa-rate treatment sessions,with follow up for2～8years.The therapeutic results of the last session CBTXA injections were analyzed in comparison with the first session.Result.CBTXA purity was high[（2.55～2.60）×10 7 LD50/mgPr ,A260/A280≤0.55,high molecular substance accounted for99.2%of total proteins].Long term treatment with CBTXA in patients with focal dystonia and HFS was not associated with any decline in benefit,and efficacy may improve slightly with repeat treatments.CBTXA is an excellent long-term treatment of HFS,BS and CD.Conclusion.We conclude that Chinese type A botulinum toxin is of botulinum toxin therapy quality standard according to results obtained from the basic study and long?term clinical applications.The re?injection of CBTXA significantly improves the quality of life of most patients and is a safe,effective and comparatively economical treatment for patients with focal dystonia and HFS.Keywords：botulinum toxin type A;focal dystonia;hemifacial spasm5|29|8Updated：2024-04-10
- Abstract：Objective.To investigate the protective effects of melatonin（MT ）on cardiomyocytes against the ox-idative injury induced by H 2 O 2 .Methods.Ventricular myocytes were isolated from neonatal rats and cultured for3～5days.Cells were divided into4groups:control group,H 2 O 2 （100μmol/L H 2 O 2 ）group,MT group（100μmol/L MT ）and MT preconditioning group（100μmol/L MT+100μmol/L H 2 O 2 ）.The fluorescent probe,DCFH?DA,was used to detect intracellular levels of reactive oxygen species（ROS）and another fluorescent probe,Fluo-3?AM,was used to detect[Ca 2+ ] i by using a laser scanning confocal microscopy（LSCM）.The malondi-aldehyde（MDA）content in cardiomyocytes was determined by measuring thiobarbituric acid?reactive sub-stances to monitor lipid peroxidation.The activity of cytoplasmic enzyme lactate dehydrogenase（LDH）that was released into the culture media was assayed to indicate alternation in the integrity of the cellular membrane.Trypan blue exclusion was used to detect the cell viability.Results.Compared with the control group,intracellular ROS,[Ca 2+ ] i ,MDA content ,LDH leakage and cell death were significantly elevated when cells were treated by100μmol/L H 2 O 2 for60minutes（P<0.01）.However,those changes were significantly attenuated in MT preconditioning group.Conclusion.MT has very good antioxidant effect and can protect the cardiomyocytes against H 2 O 2 -in-duced injury.Keywords：melatonin;cardiomyocyte;oxidative injury4|16|0Updated：2024-04-10
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