Biomedical subjects

Y Yang

Publications and source records attributed to Y Yang.

At least 811 records · Page 45Linked to original sources

PubMed1998

Preparation and characterization of monoclonal antibody against recombinant human tissue factor pathway inhibitor.

OBJECTIVE: To prepare and identify monoclonal antibody (McAb) against recombinant human tissue factor pathway inhibitor (rhTFPI) and to use it for measurement of TFPI by ELISA, and to evaluate the effects of the McAb on dilute prothrombin time (PT) and activated partial thromboplastin time (APTT). METHODS: After intrasplenic immunization of Balb/c mouse with TFPI, hybridoma technique was used to raise monoclonal antibody against rhTFPI. The McAb was well-characterized and labelled with horseradish peroxidase (HRP) by using assay of TFPI in ELISA. Furthermore, the McAb was added to normal and factor IX deficient plasma for observation of dilute PT and APTT. RESULTS: Two hybridomas (4F4, 4F8) secreting McAb against TFPI were established. The Ig class and subclass of the McAb purified from 4F8 was IgG1. Immunoblotting results indicated that the McAb4F8 only recognized a single band of TFPI with molecular weight of 34.8 KD. The results of Sandwich enzyme-linked immunosorbent assay (ELISA) by using the HRP labelled McAb4F8 showed that the mean of TFPI in normal human plasma is 103.2 +/- 11.5 micrograms/L. The McAb 4F8 was also proved to shorten markedly dilute prothrombin time of factor IX deficient plasma and normal plasma. CONCLUSIONS: We established two hybridomas cell lines (4F4, 4F8) and obtained the McAb4F8 against TFPI and reported the levels of TFPI in healthy adult human plasma by Sandwich ELISA with HRP labelled McAb4F8 in Chinese.

Animals↗

PubMed1998

Experimental study on distribution of serotypes and antimicrobial patterns of group B streptococcus strains.

OBJECTIVE: To obtain information on the distribution of serotypes and antimicrobial agent susceptibilities to group B streptococcus (GBS) strains isolated in Beijing area from 1991 to 1996. METHODS: Bacterial isolates of GBS were obtained from vaginal and cervical tract of pregnant and nonpregnant women in Beijing Tian Tan Hospital by culture. A total of 76 GBS strains were identified finally by coagglutination. Serotyping was determined by Standard Lancefield method. Susceptibility to test agents was assessed by determining the minimal inhibitory concentrations (MICs) with agar dilution method that was established by the National Committee for Clinical Laboratory Standards (NCCLS). RESULTS: Seven serotypes were identified among 76 GBS strains isolates. Types II (33%), III (23%) and I a (16%) were the predominant serotypes in pregnant and nonpregnant women. MICs of penicillin G and ampicillin were < or = 0.06 microgram/ml. MICs of cephazolin, cefuroxime and cefoperozone were 0.003 microgram/ml-0.06 microgram/ml. MICs of erythromycin were 0.003 microgram/ml-0.03 microgram/ml. MICs of gentamycin were 1 microgram/ml-32 micrograms/ml. MICs of amikacin were 4 micrograms/ml- > or = 64 micrograms/ml, nearly 12.8% and 40.4% of the strains were resistant to gentamycin and amikacin, respectively. CONCLUSIONS: Our study provides useful epidemiologic data for preparation of GBS type-specific vaccines which can prevent GBS infections and antimicrobial agents susceptibility patterns in China. Routine reports on GBS susceptibilities by clinical laboratories and continuous surveillance for changes in the susceptibility are of considerable clinical importance.

Adult↗

PubMed1998

Myospasm of internal anal sphincter in children.

OBJECTIVE: To introduce a common but not well-recognized acute abdominal disease in children. METHODS: Thirty-eight children with spasm of the internal anal sphincter were reviewed. RESULTS: The main symptom was the sudden onset of continuous pain in the lower abdomen with paroxysmal exacerbation. The typical sign was the dilation of the sigmoid colon with tenderness aggravated by pressure. Plain X-ray films showed dilation of the sigmoid colon and rectum. The symptoms could be relieved by digital rectal examination or a glycerin suppository. CONCLUSIONS: It is the temporary achalasia of the internal anal sphincter that causes acute abdominal pain.

Abdominal Pain↗

PubMed1998

[Expression of thrombopoietin related genes in patients with idiopathic thrombocytopenic purpura].

OBJECTIVE: To explore the expression of thrombopoietin (Tpo) and its receptor c-mpl in bone marrow from patients with idiopathic thrombocytopenic purpura(ITP). METHODS: Non-radioactive in situ hybridization was used to detect tpo, c-mpl mRNA. Immune cytochemistry was used to detect MPL on megakaryocyte. RESULTS: The expression of tpo, c-mpl mRNA in bone marrow and MPL on megakaryocyte in patients with ITP was increased. CONCLUSION: c-mpl mRNA was regulated at transcriptional level. A negative feedback loop was involved in the regulation of megakaryopoiesis in bone marrow. MPL may be involved in the regulation of circulating Tpo.

Bone Marrow Cells↗

PubMed1998

[Determination of Ondansetron in injection by high performance capillary zone electrophoresis].

Ondansetron is a kind of drug which is used for the treatment of nausea and vomiting induced by cytotoxic chemotherapy and radiotherapy. In this paper, a method to determine Ondansetron in injection by high performance capillary zone electrophoresis is discussed. The injection was directly introduced into the capillary employing 40 mmol/L phosphate at pH 4.03 as buffer. The capillary used was 75 microns in i.d. and 47 cm in length. UV detection was set at 254 nm. The calibration curve showed good linearity. The recovery of Ondansetron ranged from 95%-98% with a coefficient of variation of 1.05%(n = 4). This method is simple, rapid and reliable.

Antiemetics↗

PubMed1998

[Detection and identification of the DNA between Mycobacterium tuberculosis and Mycobacterium nontuberculosis by triplex polymerase chain reaction technique].

OBJECTIVE: To improve the specificity and sensitivity of polymerase chain reaction (PCR) technique for detecting and identification of DNA of M. tuberculosis and M. nontuberculosis. METHOD: Three pairs of oligonucleotide primer were used in triplex-PCR. A 383 bp DNA fragment encoding part of the 65,000 mycobacterial surface antigen, a 123 bp fragment corresponding to a specific M. tuberculosis complex sequence which was the insertion sequence 6110 (IS 6110) and a 268 bp fragment for human beta-globin were amplified by triplex-PCR respectively. RESULT: The sensitivity of the triplex-PCR-electrophoresis for the DNA of mycobacterium was 0.6 pg. The specific bands of 383 bp and 123 bp among the amplified DNA from M. hominis, M. bovis, BCG and M. simiae were present in the agarose gel. By contrast, only a band of 383 bp was found among the M. nontuberculosis which contained M. avium, M. chelonae, M. scrofulaceum, M. xenopi, M. kansasii, M. intracellulare and M. smegmatis. Compared with the standard strains, there was an additional 268 bp band in simulated clinical samples infected by Mycobacterium. The above 3 specific bands were found neither in other 15 bacterial species tested nor in Mycoplasma pneumoniae. 182 clinical samples were examined by culture, smear and triplex-PCR. 72 nontuberculous clinical samples were all negative. In 110 tuberculosis clinical samples, the positive rates were 2.7%, 13.6% and 32.7%, respectively. CONCLUSION: The triplex-PCR possesses a high specificity and sensitivity. This method could detect and identify the DNA of M. tuberculosis and M. nontuberculosis except M. simiae. It is a valuable tool for early diagnosis and differentiation for infection of M. tuberculosis and M. nontuberculosis.

Adolescent↗

PubMed1998

[Clinical study of CPD4-PDT for the prevention of postoperative recurrence in infiltrative bladder cancer].

OBJECTIVE: To assess the efficacy of chlorophyll derivative (CPD4)-Photodynamic therapy (PDT) in preventing postoperative recurrence of the infiltrative cancer of the urinary bladder. METHODS: Thirty-two patients were treated with CPD4-PDT postoperationally to prevent the recurrence of cancer, all of which being followed up. RESULTS: The recurrence rate was 42.1% in T2 tumors and 69.2% in T3 tumors (P < 0.05), and the survival period without tumor has been 19.8 +/- 14.8 months in T2 tumors, and 22.67 +/- 19.72 months in T3 tumors (P > 0.05). There was very significant difference in recurrent rate between grade I and grade II, III patients (0 and 66.7%, P < 0.001). CONCLUSION: CPD4-PDT is a safe and effective measure to prevent the recurrence in infiltrative bladder cancer after operation.

Adult↗

PubMed1998

[Application of VNTR D17S30 locus polymorphism in the paternity test].

A sensitive and rapid PCR-based technique was adopted to genotype the VNTR D17S30 locus. It was confirmed through the genetic analysis of 20 normal families that the inheritance of D17S30 locus coincides with Mendelian law as simple co-dominant. Retrospective analysis of 100 paternity cases demonstrated that D17S30 locus could be used in forensic paternity test in our country. The exclusion probability estimated from allele frequencies of D17S30 locus (74.04%) does not differ significantly from the observed rate of exclusion (80.00%) in these cases. In all excluded paternity cases there are two in which the exclusion evidence is solely provided by the D17S30 locus.

Chromosomes, Human, Pair 17↗

PubMed1998

[The effect of antioxidant sodium ferulate on human lymphocytes apoptosis induced by H2O2].

OBJECTIVE: Sodium ferulate is a potent antioxidant purified from ferula assafoetida L. The effect of sodium ferulate on apoptosis of human lymphocytes induced by H2O2 in vitro was studied. METHODS: Apoptosis was detected by light and electron microscopic, DNA electrophoresis and Flow cytometric cell cycle analysis. mitochondrial function was detected by MTT method. BCL-2 and Bax expression was detected by confocal laser scanning microscope. RESULTS: The morphological and biochemical changes characteristic of apoptosis were partially restored after treatment with sodium ferulate, Immunofluorescence assay showed a decrease in BCL-2 and an increase in Bax oncogene proteins in lymphocytes treated with H2O2 and an improvement of cell apoptosis was found after sodium ferulate treatment. CONCLUSION: Oxidative stress can induce apoptosis in lymphocytes, and this induction can be partly prevented by sodium ferulate.

Apoptosis↗

PubMed1998

[Experimental study on treatment of viral myocarditis in mice by integrated traditional Chinese and Western Medicine].

OBJECTIVE: To clarify the effects of Astragalus Membranaceus (AM) combined with taurine and/or coenzyme Q10(CoQ10) on coxsackievirus B3 (CVB3) murine myocarditis. METHODS: Viral myocarditis model was created by intraperitoneal inoculation with CVB3 solution and were treated by saline, AM, taurine, CoQ10, AM + taurine, AM + CoQ10, AM + taurine + CoQ10, respectively. The mortality, ECG, CVB3-RNA in myocardium and myocardial histopathologic changes were observed. RESULTS: AM combined with taurine and CoQ10 could significantly reduce the mortality of the mice and the incidence of abnormal ECG at acute stage. CVB3-RNA was significantly reduced in AM treated group, especially in AM + taurine group. No anti-virus effect was found in CoQ10 group. All drugs could lighten myocardial histopathologic changes and the effect could be enhanced by combined treatment. CONCLUSIONS: AM, taurine and CoQ10 have some curative effects on CVB3 murine myocarditis, AM combined with taurine and CoQ10 is the best.

Animals↗

PubMed1998

[Comparing the bronchodilating effects of ipratropium bromide and theophylline].

OBJECTIVE: To compare the bronchodilating effects of ipratropium bromide and theophylline in chronic obstructive pulmonary disease(COPD). METHOD: In 26 patients, mean peak forced expiratory volume in 1 second(FEV1) were measured at the time before and 30 minute, 1, 2, 3, 4, 5, 6 hours after the drugs were administered in a double-blind, placebo-controlled crossover method. RESULT: The mean peak of FEV1, increased over baseline were 34% and 19% respectively, for ipratropium bromide and theophylline (P < 0.01), and the reaching duration were 1-2 hours and 2-3 hours, the proportion of patients attaining at least a 15% (P < 0.01) increase in the FEV1, responders were 19% and 50% (P < 0.01) respectively, for ipratropium bromide and theophylline. The average FEV1, increased during the 6-hours observation period were 18% for ipratropium bromide and 8% for theophylline (P < 0.01). The mean duration of FEV1 > 15% was 3.6 and 1.6 hours respectively. CONCLUSION: Ipratropium bromide nebulized is a more potent bronchodilator than the oral theophylline in patients with chronic airflow obstruction.

Adult↗

PubMed1998

[Changes of T-SOD activity and MDA, GSH contents in blood of guinea pigs after exposure to narrow-band noise].

In order to evaluate the changes of lipid peroxide response induced by free radical after intense noise exposure, levels of T-SOD and MDA in serum and GSH in blood of guinea pigs were determined. Sixty male adult guinea pigs were used. The narrow band noise was centered at 1000Hz with 100Hz band width 126 dB SPL. It was found: 1) SOD activity in serum increased after 5d exposure (P > 0.05), but decreased after 10d exposure (P > 0. 05); 2) contents of MDA in serum increased (P < 0.05) and contents of GSH in blood decreased with increase of exposure time (P < 0.01). It shows that the lipid peroxide response induced by free radicals increased after intense noise exposure and it is possible to use free radical scavengers and/or antioxidant in prevention and treatment of noise induced damage.

Animals↗

PubMed1998

[Ileocolonic pouch with appendix in situ through umbilicus as a continent conduit].

OBJECTIVE: To try to use appendix in situ without any special treatment as a conduit of the continent cutaneous ileocolonic reservoir. METHODS: An isolated ileocolonic segment, about 20 cm of terminal ileum and 20 cm of ascending colon, was detubularized by antimensenteric splitting and a pouch was completed by side-to-side anastomosis of the colon and the ileum loop. Both ureters were implanted into two separate submucosal tunnels of 3 cm long into the colon wall of the pouch. The appendix after tail was amputated was passed through the umbilicus hole with which the base of the cecum was sutured. RESULTS: As a conduit of the pouch, the appendix had a good continent ability when 8 patients were followed up for 10 to 30 months after operation. It was easy and convenient for the patients to make self-catheterization. The mean capacities of the pouch were 500-700 ml and then the pressures were 20-45 cm H2O while it was filled. There were no definite complications such as urine leakage, stoma stenosis, ureter reflux, and hydroureteronephrosis. CONCLUSION: The operation of the ileocolonic pouch with the appendix as a continent umbilical stoma is simple and easy to perform and has such advantages as good continent, convenient self-catheterization and provides a quality life for the patients undergoing total cystectomy.

Adult↗

PubMed1998

Comparative effects of losartan and captopril on ventricular remodeling and function after myocardial infarction in the rat.

OBJECTIVE: To determine the effects of losartan and captopril treatment on ventricular remodeling and function after myocardial infarction in rats. METHODS: Thirty-two rats with MI induced by coronary ligation after seven days were divided into four groups randomly and treated with captopril(2 g.liter-1, group A), losartan(10 mg.kg-1.d-1, group B), losartan(30 mg.kg-1.d-1, group C) and placebo (no drug, group D) for six weeks, respectively. Sham-operated rats(group E) served as controls. Echocardiography was performed at 1 and 7 weeks after MI, respectively. RESULTS: Compared with the results before treatment, both LV end-diastolic internal diameter and volume decreased significantly and the thickened posterior wall was reversed in group A, B and C; the peak early filling velocity decreased whereas the peak velocity was increased in these three groups. There are no significant difference among the three treated groups. However, LV end-diastolic internal diameter and the E/A were still increased, whereas the thickness of anterior wall and the peak velocity of LV outflow were decreased in group A, B, and C after treatment comparing with group E. CONCLUSION: Both angiotensin converting enzyme inhibitor and angiotensin II receptor antagonist can prevent the ventricular remodeling and improve the ventricular function.

Angiotensin Receptor Antagonists↗

PubMed1998

[Thoracoscopic lung reduction surgery for emphysema].

OBJECTIVE: To study the surgical treatment of emphysema. METHOD: Five patients with severe diffused pulmonary emphysema underwent surgical bilateral lung volume reduction by video-assisted thoracoscopy. All patients were male and their age ranged from 60 to 71 years (mean 64.3 years). Before surgery, 5 patients required supplement oxygen with exertion and one oxygen supplement at rest. Preoperative and postoperative assessments included standard pulmonary function studies, chest CT scan and quantitative nuclear lung perfusion and ventilation scan. Wedge resection was performed were in 3 patients, simple plication in 1, and combined wedge resection and plication in 1. There were no early or late mortality and no requirement for immediate postoperative ventilatory assistance. RESULT: Follow-up ranged from 10 to 12 months. After surgery the mean forced expiratory volume in 1 second (FEV(1)) was significantly increased from 0.46 L to 1.13 L (P < 0.001) and the mean forced vital capacity (FVC) was markedly improved from 1.74 L to 2.93 L (P < 0.001). Pulmonary compliance was significantly improved and resistance of airway decreased (P < 0.001). The mean distance during 6-min walk test increased from 10 m to 400 m in 4 patients. CONCLUSION: Thoracoscopic bilateral lung volume reduction is an effective and safe technique for patients with severe emphysema. It can relieve dyspnea and improve in excise tolerance and quality of life.

Aged↗

PubMed1998

[Clinical application of 2 mm micro-thoracoscopic surgery].

OBJECTIVE: To determine the clinical safety and efficacy of micro-thoracoscopic surgery. METHOD: From July 1996 to July 1997, video-assisted thoracoscopic surgery was performed in 47 patients by using 2 mm microthoracoscope. There were 36 males and 11 females. Their age ranged from 40 to 75 years with a mean age of 56.7 years. Surgical procedures included bullectomy (16 patients), wedge resection (3), lung cancer staging (4), lobectomy (2), exploration (15), and resection of mediastinal tumor (2), esophagectomy (1) and repair of pneumothorax (4). Local anesthesia was employed in 18 patients and general anesthesia with double lumen endotracheal tube in 29. RESULT: There were no operative mortality and postoperative complications. CONCLUSION: 2 mm micro-thoracoscopic surgery could be used in the management of a variety of thoracic conditions. It may be of significant value for diagnostic and therapeutic purposes, but the further study for this new technique is required to determine its safety and efficacy.

Adult↗

PubMed1998

[Diagnostic value of serum creatine kinase MB in patients with cardiac damage after electric injuries].

OBJECTIVE: To investigate the incidence of cardiac damage and the diagnostic value of serum myocardial enzyme following electric injuries. METHOD: 32 patients with electrical contact injuries were evaluated by serial electrocardiograms (ECG), creatine kinase (CK) and creatine kinase MB isoenzyme (CK-MB) determinations. The patients were divided into two groups according to the ECG. RESULT: 17 patients showed abnormal ECG (Group A), and 15 normal ECG (Group B). Positive correlations were noted between CK, CK-MB and the size of electric burns. The difference of serum CK-MB and 1.1% of total CK (CK-MB in skeletal muscle) was defined as CK-MB difference. CK, CK-MB, CK-MB/total CK ratio and the CK-MB difference were significantly higher in group A than in group B (all P < 0.05). The CK-MB difference of 88% (15/17) patients in group A was more than 25 U/L, whereas that was 6.7% (1/15) in group B (P < 0.01). Six patients with CK-MB difference greater than 100 U/L had obvious cardiac damage. CONCLUSION: Cardiac damage is a common complication of electric injuries. The cardiac damage could be estimated by serum CK-MB, particularly by the CK-MB difference. The CK-MB difference might be a useful indicator for evaluating the severity of the cardiac damage.

Adolescent↗

PubMed1998

[Malakoplakia of the prostate].

OBJECTIVE: To study the diagnosis and treatment of prostatic malakoplakia. METHOD: Two cases of malakoplakia were reported, and the cases and articles were reviewed. RESULT: The disease is an inflammation of the prostate, and lower immunocompetence is concomitance. The patients had symptoms of dysuria and urethralgia. The tubercle could be found. Pathological section revealed malakoplakia cells and Michaelis-Gutman inclusion bodies. Many patients were performed radical prostatectomy because of misdiagnosis. CONCLUSION: Biopsy of the prostate and antibiotics should be used clinically.

Humans↗