Biomedical subjects

J Ma

Publications and source records attributed to J Ma.

At least 217 records · Page 12Linked to original sources

PubMed2000

Clinical and analytical evaluation of an enzyme immunoassay for myelin basic protein in cerebrospinal fluid.

BACKGROUND: RIA of myelin basic protein (MBP) in cerebrospinal fluid (CSF) is commonly used as a biochemical marker of demyelination in patients with multiple sclerosis (MS). Our aim was to develop a sufficiently sensitive ELISA for MBP and evaluate it clinically in patients with MS. METHODS: The ELISA used anti-bovine MBP antibody coated on plates and biotinylated anti-MBP antibody. The bound antibody complex was quantified with streptavidin-horseradish peroxidase. MBP was determined in CSF from 84 MS patients and 55 patients with other neurological diseases. RESULTS: The respective within- and between-assay CVs were 4.7% and 7.2% at 200 ng/L, and 6. 3% and 8.8% at 2000 ng/L. The detection limit was 30 ng/L. Most of the MS patients with acute exacerbations had markedly increased MBP in the CSF. Longitudinal studies of six MS patients with recurrent exacerbation confirmed this observation. MBP concentrations from 78 MS patients, as tested with our ELISA, correlated well with those obtained by RIA (r = 0.9; P: <0.01), but the detection limit of the ELISA was much lower than that of the RIA. CONCLUSIONS: This convenient ELISA with higher sensitivity than the existing assays is a suitable routine assay that provides a diagnostic indicator of myelin breakdown in the central nervous system; moreover, it is an excellent indicator of MS disease activity.

Adolescent↗

PubMed2000

[An experimental study on arsenic trioxide-selectively induced human hepatocarcinoma cell lines apoptosis and its related genes].

OBJECTIVE: To study the possible apoptosis-inducing effect of arsenic trioxide on human hepatocarcinoma (HCC) cells, and its molecular mechanisms. METHODS: Arsenic trioxide action on the cell growth, apoptosis, periodicity and the expression of related genes in two human hepatocarcinoma cell lines QGY-7701 and QGY-7703, and normal humanhepatic cell line L-02 in vitro was observed by MTT assay, acridine orange (AO) /ethidiumbromide (EB) fluorescent staining, electron microscopy detection, DNA gel electrophoresis, flow cytometry, TUNEL assay and immunohistochemical staining. RESULTS: Arsenic trioxide could strongly inhibit the growth of human hepatocarcinoma cells QGY-7701 and QGY-7703 with the cell cycle arrested on S phase, and induce the apoptosis of the cells with bcl-2 gene expression down-regulated and bax and Fas gene expression up-regulated. But arsenic trioxide had no obvious effect on the normal hepatic cells. CONCLUSION: Arsenic trioxide has significant selective apoptosis-inducing effect on the human hepatocarcinoma cells, which is regulated by several genes. The results provide the credible experimental basis for clinically treating HCC with arsenic trioxide.

Antineoplastic Agents↗

PubMed2000

[Study on hepatitis B virus infection status in placentas of hepatitis B surface antigen positive pregnant women during middle and late period of pregnancy].

OBJECTIVE: To investigate Hepatitis B Virus (HBV) infection status in placentas of Hepatitis B Surface Antigen (HBsAg) positive pregnant women during middle and late period of pregnancy. METHODS: One hundred and sixty-seven placentas from HBsAg positive pregnant women were collected, including 158 term placentas and 9 aborted second-trimester placentas. HBsAg and hepatitis B core antibody (HBcAg) in placental cytotypes were detected by immunohistochemistry. RESULTS: Of the 158 term placentas, HBV infection rates in decidual cells (DC), trophoblastic cells (TC), villous mesenchymal cells (VMC) and villous capillary endothelial cells (VCEC) were 66.46% (105/158), 58.23% (92/158), 27.22% (43/158) and 12.66% (20/158), respectively. The HBV infection rates gradually decreased from maternal side to fetal side of placentas. Both HBsAg and HBcAg were mainly located in the cytoplasm of infected cells. The positive cells were mostly in focal distribution. One out of 9 aborted second-trimester placentas was infected. CONCLUSIONS: HBV infection was found in different cells of term placentas. The positive rates for HBsAg and HBcAg in placentas were gradually decreased from maternal side to fetal side. The positive rate was low in aborted second-trimester placentas.

Adult↗

PubMed2000

[Molecular cytogenetic study of bladder transitional cell carcinoma by FISH].

OBJECTIVE: To study the molecular cytogenetic alterations of transitional cell carcinoma of the urinary bladder with exfoliated cells. METHODS: Fluorescence in situ hybridization (FISH) was performed using centromeric probes of chromosome 7, 9, 11 and 17 to examine chromosome aberration of exfoliated cells in 34 urine samples and 30 bladder washings from patients with transitional cell urinary bladder carcinoma. RESULTS: (1) The frequency of numerical aberration of chromosome 7, 9, 11, 17 was 23.5%, 38.2%, 14.7% and 11.8% in urine and 30.0%, 50.0%, 26.7% and 16.7% in bladder washing, respectively. Loss of chromosome 9 was the most common finding, but it was not correlated with pathological grade of cancer and stage of the disease. Abnormality of chromosome 7 was however associated with the clinical stage. (2) The positive rate of examination by cytology and FISH was 29.4% and 55.9% in urine, 27.6% and 73.7% in bladder washing, respectively. When the results of cytology and FISH were combined, the positive rate increased to 67.6% and 80.0% for urine and bladder washing, respectively. CONCLUSION: A number of chromosome aberrations is detected in transitional cell carcinoma of the urinary bladder by FISH technique which provides a basis for further understanding of its molecular pathogenesis and clinical applications.

Adult↗

PubMed2000

[Experimental study on effect of bushen yijing recipe in delaying senility of bone and brain of aged male rats].

OBJECTIVE: To evaluate the effect of Bushen Yijing recipe (BSYJR) in delaying senility of bone and brain of aged male rats and infer its mechanism in delaying systemic senility. METHODS: Forty male SD rats, 24 months old were randomly divided into 4 groups, the baseline control group, the aged control group (30 months old), the BSYJR high dose group and the BSYJR low dose group. The latter two groups received BSYJR treatment from 24 months old to 30 months old. Bone indexes (bone density of the proximal, middle and distal segments of left femur and break bending load of right femur) and brain indexes (binding capacity of M receptor and cholinesterase activity of brain) were measured after responding treatment. RESULTS: In bone, BSYJR could not only increase the bone mineral density in various segments of femur, but also raise the bending break load of femur dose-effect dependently. In brain, BSYJR could both up-regulate the binding capacity of M receptor and inhibit the activity of cholinesterase. CONCLUSION: BSYJR could delay the senility of bone and brain in male rats, inferring that it might regulate integrally the abnormality of aging in Kidney Asthenia and Essence Deficiency through mediation of nerve-endocrine-immunity network.

Aging↗

PubMed2000

[Combined five tumor markers in detecting primary hepatic carcinoma].

OBJECTIVE: To increase the detection rate of primary hepatic carcinoma (PHC) and to diagnose PHC earlier. METHODS: AFP was combined with r-glutamyle transpeptidase (r-GT), alpha-fucosidase (AFU), tumor necrosis factor-alpha (TNF-alpha) and DR-70. RESULTS: The positive detection rate of PHC negative AFP with combined four markers was 9.4%. The total positive detection rate of PHC with combined five tumor markers reached 98.0% which was significantly higher than that with AFP (P < 0.01). CONCLUSIONS: The positive detection rate of PHC can be increased by combined five tumor markers. It is helpful in diagnosing PHC earlier and can differentiate PHC from liver cirrhosis.

Biomarkers, Tumor↗

PubMed2000

[Annular constriction of popliteal vein for treating severe venous insufficiency].

OBJECTIVE: To study the mechanism and therapeutic effects of annular constriction for severe venous insufficiency of legs. METHODS: Annular constriction of popliteal vein was performed by Gore-Tex vascular graft in 82 patients. Among them, 78 patients had deep venous valve insufficiency of legs (III, IV degree), 2 postphlebitic syndrome, and 2 valve absence of deep vein. Under normal respiration and breath holding, venous pressure was measured at the proximal and distal part from the constricting site. RESULTS: Great difference was noted in the venous pressure between the proximal and distal part from the constricting site. The pressure was (9.4 +/- 4.5) mm Hg, (41.2 +/- 28.1) mm Hg at calm and (32.4 +/- 16.2) mm Hg, (41.2 +/- 28.1)mm Hg at breath holding (P < 0.01). Symptoms disappeared or released after operation. Ulcer healed in all patients. Venous pressure decreased by over 60%. Pressure recovery time was over 22 seconds. There was no reflux distal to the constricting site. Deep venous angiography and color Doppler showed an effect similar to venous valve. CONCLUSION: Annular constriction is effective in treating severe venous insufficiency of legs.

Constriction↗

PubMed2000

[Microcirculation of thoraco-acromial flaps: monitoring and clinical application].

OBJECTIVE: To monitor the microcirculation of thoraco-acromial flaps. METHODS: The microcirculation in 12 thoraco-acromial flaps was monitored continuously by laser Doppler flowmetry (LDF). RESULTS: The microcirculatory changes in thoraco-acromial flaps were divided into two phases: rapid rising (2 - 4 days after operation) and plateaurising (4 - 7 days after operation). PU values were 7.4 +/- 2.0, 7.6 +/- 2.3 and 7.3 +/- 1.6. CONCLUSIONS: In division of the thoraco-acromial flaps within the plateau, the value (PU) returned to or exceeded 50% of that before application of the tourniquet. All flaps survived. The time of division was decreased to 6 - 8 after operation days.

Adolescent↗

PubMed2000

[Simultaneous nasal reconstruction and facial defect repair using expanded forehead flap].

OBJECTIVE: To improve the method for the repair of facial defect using expanded forehead flap. METHODS: 10 patients were treated with the expanded forehead flap for total nose reconstruction and repair of facial defects. The expanded flap was divided two parts: the supratrochlear vessels for nasal reconstruction and the frontal branch of the superficial temporal vessels for facial defects. The periorbital or zygomatic area, the upper or lower lip. The defect of the forehead donor site was directly closed. RESULTS: Nasal reconstruction and repair of facial defects were satisfactory in all patients. CONCLUSION: Nasal reconstruction and simultaneous repair of facial defects extend the scope of use of expanded forehead flap.

Adolescent↗

PubMed2000

[Primary study on immunologic effect of live attenuated hepatitis A vaccine (H2 strain) after booster dose].

OBJECTIVE: To study the immunologic effect of live attenuated hepatitis A vaccine (H(2) Strain, 10(7.0)TCID(50)) after booster and to compare with the results of 1 dose live attenuated hepatitis A vaccine (H(2) Strain, 10(7.0)TCID(50)). METHODS: 42 susceptibles with negative anti - HAV were selected in Zhengding, Hebei province. Each subject received 3 doses live attenuated hepatitis A vaccine at 0, 2, 6 months and was bled at 1, 2, 6, 7, 9, 12 months after vaccination. RESULTS: The seroconversion rate at 1 month after the first dose was 81.4% and reached 100% after the second dose. GMT arrived the peak 2,739 mIU/ml at one month after the third dose, before stared declining. The seroconversion rate kept 100% at 12 months after the first dose, but GMT decreased to 979 mIU/ml. CONCLUSION: The first dose worked as the base of boostering. A booster dose of live attenuated hepatitis A vaccine could induce secondary immune response well. The immunologic effect after booster dose could match the effect with inactivated vaccine and was better than the results of 1 dose live attenuated hepatitis A vaccine. The program seemed to be useful to the protective effect and the immuno - persistence.

Child↗

PubMed2000

[Preliminary study on relationship between antibody against heat stress protein 70 and hypertension].

OBJECTIVE: To preliminarily explore the relationship between main antibody against heat stress protein 70 (anti-HSP70) and hypertension. METHODS: Serum anti-HSP70 was determined with Western blotting technique in hypertensive and normotensive groups. Logistic regression model was used to analyze the relationship between anti-HSP70 and hypertension. RESULTS: It was found that level of antibody against the main heat shock protein 70 was significantly higher in patients with hypertension (based on criteria of 160/95 mm Hg, 1 mm Hg = 0.133 kPa) than in controls, after adjustment for the generally recognized risk factors for hypertension (such as age, sex, length of employment, body mass index, job, et al.). There still was stronger association between anti-HSP70 and hypertension (based on criteria of 140/90 mm Hg), but its strength of association was weaker than the former. CONCLUSIONS: Anti-HSP70 may potentially serve as a serum biomarker to assess hypertension, or anti-HSP70 itself may be involved in the development of hypertension.

Autoantibodies↗

PubMed2000

[Clinicopathologic study of angiogenesis in human hepatocellular carcinoma].

OBJECTIVE: To study clinicopathologic significance of microvessel density (MVD) and the expression of vascular endothelial growth factor (VEGF) in human hepato-cellular carcinoma (HCC). METHODS: 30 HCC cases with neighboring noncancerous tissues, 10 liver cirrhosis cases, 5 mild chronic hepatitis cases and 4 normal liver tissue samples were stained with CD34, VEGF by immunohistochemistry method. Quantitation of sinusoid-like vessels and semi-quantitation of VEGF expression were performed and analyzed in conjunction with the clinico-pathological features of HCC. RESULTS: All HCC tissues showed diffuse CD34 expression and its site of distribution was somewhat corresponding to the original structure of sinusoid-like pattern, while CD34 was negative in the "sinusoid" regions of normal and chronic liver disease. Both MVD and VEGF were correlated to portal vein invasion of HCC, MVD was also correlated to the tumor size. The MVD of tumor less than 2 cm in diameter was significantly lower than that of tumors with a diameter of 2 similar 5 cm. The positive rate of VEGF in HCC was 83.3%. The expression of VEGF was also remarkable in the neighboring noncancerous tissues in which inflammatory cell infiltration was apparent. CONCLUSIONS: MVD and expression of VEGF were remarkably increased in HCC. Both were correlated with portal vein invasion. VEGF derived from tumor cells and noncancerous tissues may be associated with the angiogenesis of HCC.

Adult↗

PubMed2000

[Apoptosis of human gastric cancer cell line MGC-803 induced by glycyrrhiza uralensis extract].

OBJECTIVE: To study the apoptosis in human gastric cancer cell MGC-803 induced by the extract of glycyrrhiza uralensis Fisch. METHODS: Apoptosis was detected by laser scanning confocal microscope, agarose gel electrophoresis and flow cytometry. The p53 gene expression was analyzed by double immunolabelling and immunohistochemistry technique. RESULTS: Chromatin condensation of different phases of apoptotic cells were observed by laser scanning confocal microscope, the percentage of apoptosis determined by flow cytometry was time- and dose-dependent, agarose gel electrophoresis of DNA exhibited obvious "ladder" in the cells treated with higher concentration of the extract of glycyrrhiza uralensis. The p53 gene expression was unchanged after treatment. CONCLUSION: Glycyrrhiza can induce human gastric cancer cell line MGC-803 to apoptosis by p53-independent pathway and can be used as a potential, natural apoptosis-inducing agent for gastric cancer therapy.

Apoptosis↗

PubMed2000

[Determination of furostanol saponins in Bulbus Allii Macroste].

OBJECTIVE: To establish an Ehrlich reaction-colorimetry method for determining furostanol saponins in Bulbus Allii Macroste. METHOD: Based on the coloration reaction between furostanol saponins and p-dimethylaminobenzaldehyde, the UV detection wavelength used was 515 nm, and the optimum conditions were selected on homogeneous design principle. RESULT: The standard curve of macrostemonoside G was linear in the concentration range of 0.1975-0.9880 mg.ml-1. The average recovery was 97.7% (RSD = 3.65%). CONCLUSION: The method is rapid, accurate and easy to operate.

Allium↗

PubMed2000

[Experimental studies on rabbit facial nerve regeneration in chitin tubes containing nerve growth factor].

OBJECTIVE: To evaluate the nerve regeneration after implantation of chitin tubes containing nerve growth factor(NGF) in the rabbit facial nerve. METHODS: Bilateral 8 mm defect of superior buccal divisions of the facial nerves were made in 16 New Zealand rabbits. Chitin tubes containing NGF were implanted into the gaps, and autologous nerves were implanted into the right gaps as control. The nerve regeneration was evaluated with electrophysiological and ultrastructural examination after 8 and 16 weeks of operation. RESULTS: Chitin tubes containing NGF successfully induced the nerve regeneration, regularly arranged myelinated and unmyelinated axons could be observed across the 8 mm gaps, and the myelin sheath was thick with clear lamellar structure at 8 weeks after operation, The regenerated nerve fibers increased and were more mature at 16 weeks after operation. There were no significant difference in electrical impulse conduction velocity through the neural regeneration between the experimental and control sides (P > 0.05). CONCLUSION: Chitin tubes containing NGF can provide optimal conditions for regeneration of rabbit facial nerve.

Animals↗

PubMed2000

[The development of a 64-channel epicardial potential mapping system].

A 64-channel epicardial potential mapping system was developed in order to study the mechanics of arrhythmia such as atrial fibrillation and ventricular fibrillation, and instruct the procedure of detecting and eliminating abnormal rhythm in experiment or clinic. The system was consist of electrode, amplifier, A/D card, computer and output device. The system's software include signal acquisition module, signal preprocessing module, character-point detecting module, isochrone-map construction module, output display and print module. The system could be used to detect the activation path of atrial fibrillation and ventricular fibrillation.

Algorithms↗

PubMed2000

[Ventricular wave identification in epicardial mapping system using wavelet transform].

A novel method for the identification of ventricular wave based on wavelet transform is presented. First, "Multi-Scale Intersectional Search" is adopted for analysis of wavelet transform coefficients on some different scales, then adaptive detection is used on this basis. The results of practice show that it has a discrimination of 94.5%, and is obviously superior to any routime method.

Algorithms↗

PubMed2000

Changes in myocardial contractility and contractile proteins after four weeks of simulated [correction of simulate] weightlessness in rats.

The interaction between the gravitational field, the position of the body, and the functional characteristics of the blood vessels determines the distribution of intravascular volume. In turn, this distribution determines cardiac pump function. One of the most profound circulatory changes that occurs in man during exposure to weightlessness is a cephalad redistribution of fluid caused by the lack of hydrostatic pressure in this microgravitative environment. The cephalad redistribution of fluid results in a loss of blood volume and then induces a decrease in preload. Recently, a decrease in sensitivity of arteriole to catecholamine has reported in rats of simulated weightlessness. This change in arteriole may reduce afterload. As a result, cardiovascular system may be shifted to a hypokinetic state during weightlessness condition for long-term. Echocardiographic data from astronauts during space flight showed an increase in heart rate, a 12 % decrease in stroke volume, and a 16 % decrease in left end diastolic volume. Electron-microscopic studies have shown changes in cardiac morphology in rats after exposure to microgravity for 7-12.5 days. After the COSMOS 2044 flight for 14 days, the light-microscopic studies have shown an atrophy of papillary muscles in rats left cardiac ventricle. It is not clear whether the function of atrophic myocardium is impaired. The data in three aspects as mentioned above suggest that weightlessness or simulated weightlessness may decrease the myocardial function. However, definite changes in cardiac performance have been hard to prove due to many limits. This studies were to answer two questions: Is the myocardial contractility depressed in rats subjected to simulated weightlessness for four weeks? What are the underlying mechanisms of the changing contractility?

Animals↗