Biomedical subjects

H Song

Publications and source records attributed to H Song.

At least 127 records · Page 7Linked to original sources

PubMed1999

[Clinical observation on therapeutical effect of prepared rhubarb in treating pregnancy induced hypertension].

OBJECTIVE: To study the effect of prepared rhubarb in treating patients with pregnancy induced hypertension (PIH) and its therapeutic mechanisms. METHODS: Prepared rhubarb and nifedipine were given to the study group, while the nifedipine was given to the control group alone. The blood lipid, renal function, blood coagulation, fibrinolysis and immunological parameters were monitored. RESULTS: In the study group, (1) Levels of triglycerides (TG) and low density lipoprotein-cholesterol (LDL-C) decreased and high density lipoprotein-cholesterol (HDL-C) level increased significantly; (2) Plasma level of fibronectin (FN) and plasminogen activator inhibitor (PAI) lowered significantly, plasma antithrombin (AT-III) level unchanged; (3) Serum beta 2 microglobulin (beta 2-MG) level and urinary level of N-acetyl-beta-D-glucosaminidase (NAG) and interleukin-6 (IL-6) decreased significantly; (4) CD8 of blood increased, CD4/CD8 and circulating immune complex (CIC) of blood reduced obviously. All of the above-mentioned parameters in the study group were significantly different from that of the control group. CONCLUSION: The prepared rhubarb could reduce the vascular endothelial cell's damage significantly and alter the immune balance, which is effective in treating the PIH.

Adult↗

PubMed1999

[Effect of alum on intestinal microecological balance in mice].

OBJECTIVE: To observe the degree of microecological imbalance induced by alum in normal intestine of mice, and the bacterial adherence activity in the intestine of the mice administered orally with alum. METHODS: The mice were medicated orally with alum of small and large doses (0.25 g/kg and 1 g/kg) for 8 weeks, then 5 weeks after stopping administration of alum, microflora analysis and bacterial adherence to intestinal mucosal epithelial cells were carried out respectively. RESULTS: Eight weeks after administration with alum, the counts of Bifidobacteria and Lactobacilli decreased significantly, but the numbers of pathogenetic E. Coli increased significantly. The adherence rate of Bifidobacteria to the enterocytes of mice reduced markedly, but E. Coli was on the contrary of Bifidobacteria. Five weeks after the ceasing of medication, the intestinal flora were balanced, the adherence rate of both strains as mentioned above recovered to normal level. CONCLUSION: The imbalance of intestinal flora of mice administered with alum for a long time were only the transient change of bacterial counts. The imbalance of intestinal flora and the adherence rate of bacteria regained normal status five weeks after cancelling action factor.

Alum Compounds↗

PubMed1999

[Histology and physiological function of dogs after extirpation of bronchi].

OBJECTIVE: To investigate the effect of extirpation of bronchi on histology and physiological function. METHODS: 21 dogs were divided in to two groups: control (3) and experimental (18). After bronchi extirpation one week, two weeks, one month, three months, six months, and twelve months, we used specimens to test the pulmonary surfactant (PS) and to observe the morphological changes. RESULTS: After the operation, the residual lung nearby the operative area had traumatic changes. Around the aforementioned area, the structure of lung was normal. Specially after six months, the lung returned to good status. We found that two weeks after operation, the contents of PS increased remarkably (P < 0.05). After one month the parameter returned to normal (P > 0.05). CONCLUSIONS: The residual lung after bronchi extirpation had ventilation and air-exchange functions. The lung function was preserved directly.

Animals↗

PubMed1999

[Studies on gel electrophoresis of soluble protein and two kinds of isodynamic enzyme in hongqu from different producing areas].

OBJECTIVE: To investigate the consanguinity between 12 strains of Monascus(MS 01-12) separated and purified from different samples of Hongqu collected from 12 areas in China and the variant strain of Monascus(MS 18) mutated from M. purpureus. METHOD: Gel electrophoresis of soluble protein, esterase and superoxide dismutase(SOD) was used to study the consanguinity between strains MS 01-12 and the variant strain MS 18. RESULTS: The electrochromatophoreses of soluble protein, esterase and SOD in the 12 strains (MS 01-12) are identical, but in the variant strain MS 18 are remarkably different. The results are consistent with those of morphological studies. CONCLUSION: Strains MS 01-12 are the identical species M. purpureus, but strain MS 18 is different from strains of MS 01-12, or a variant of M. purpureus.

Esterases↗

PubMed1999

[Studies on pharmacognostic identification and quality control standards for hongqu].

OBJECTIVE: To develop effective methods for quality control of the traditional Chinese drug Hongqu. METHOD: TLC and microscopic identification were performed. HPLC was used to determine the content of lovastatin. RESULT: A lot of hyphae and spores in Hongqu were observed under microscope. The spot of lovastatin was found on the TLC chromatogram. The standard curve of lovastatin by HPLC was linera in the range of 5 micrograms/ml-100 micrograms/ml. The average recovery of lovastatin was 96.4%, RSD 3.68%, n = 5. CONCLUSION: The methods are simple, sensitive and accurate. These studies provide the scientific basis for quality evaluation and quality control of Hongqu.

Chromatography, High Pressure Liquid↗

PubMed1999

[A study on soil suitability for growth of rhizome of Curcuma longa L].

OBJECTIVE: To seek for the type of soil that influences favorably the yield and quality of Curcuma longa. METHOD: Field contrast control experiment, correlation analysis, path analysis and cluster analysis were used. RESULT: The rhizome yield and quality of Curcuma longa. varied greatly with the types of soil texture. There are clear correlations among the soil factors, as well as between the soil factors and the rhizome yield and quality of the plant. A regression equation of the rhizome yield and soil factors has been built up. CONCLUSION: The soil suitable for growing Curcuma longa. can be classified into three types according to the results of correlation analysis and cluster analysis.

Curcuma↗

PubMed1999

[A study on fresh rhizome simulation model and its application to comprehensive agronomic measures for good quality and high yield of Curcuma longa L].

OBJECTIVE: To work out standardized cultivating measures for Curcuma longa according to the analysis of fresh rhizome simulation model. METHOD: Second order orthogonal rotative regression design. RESULT: The fresh rhizome simulation model was built up, and 5 main measures that affect fresh rhizome yield were analyzed by the mathematical model of five unknowns second order orthogonal rotative regression. Sowing time, plant population and potassium play an important role in raising the fresh rhizome yield. Sowing time is clearly interrelated with plant population, and plant population is clearly interrelated with the fertilizer used Sufficient N and K are necessary for raising the yield. There is a clear interrelation among the fertilizer factors. CONCLUSION: Optimal farming measures: sowing time March 1-17, and plant population-110,000 to 115,000 mother rhizomes per hm2. The optimal fertilizer requirements have also been formulated.

Computer Simulation↗

PubMed1998

Decoupling of nucleotide- and microtubule-binding sites in a kinesin mutant.

Molecular motors require ATP to move along microtubules or actin filaments. To understand how molecular motors function, it is crucial to know how binding of the motor to its filamentous track stimulates the hydrolysis of ATP by the motor, enabling it to move along the filament. A mechanism for the enhanced ATP hydrolysis has not been elucidated, but it is generally accepted that conformational changes in the motor proteins occur when they bind to microtubules or actin filaments, facilitating the release of ADP. Here we report that a mutation in the motor domain of the microtubule motor proteins Kar3 and Ncd uncouples nucleotide- and microtubule-binding by the proteins, preventing activation of the motor ATPase by microtubules. Unlike the wild-type motors, the mutants bind tightly to both ADP and microtubules, indicating that interactions between the nucleotide- and microtubule-binding sites are blocked. The region of the motor that includes the mutated amino acid could transmit or undergo a conformational change required to convert the motor ATPase into a microtubule-stimulated state.

Adenosine Diphosphate↗

PubMed1998

The antifungal drug clotrimazole.

The structure of the title compound, 1-[(2-chlorophenyl)diphenylmethyl]-1H-imidazole, C22H17ClN2, has been determined. The molecular conformation showed a weathercock-type structure and the three phenyl rings are almost perpendicular to the imidazole ring. The distances between the centres of the three phenyl rings and the centre of the imidazole ring are in the range 4.52-4.54 A.

Antifungal Agents↗

PubMed1998

Mutational analysis of the transforming growth factor beta receptor type II gene in human ovarian carcinoma.

In the present study, we evaluated a series of sporadic ovarian carcinomas for mutations within the entire coding region of TbetaR-II. Using reverse transcription-PCR and "Cold" single-strand conformational polymorphism analysis, 6 of 24 samples (25%) were found to contain code-altering mutations in TbetaR-II: (a) four mutations resulting in amino acid substitutions in the highly conserved serine/threonine kinase domain; (b) one mutation resulting in a conservative amino acid change in the transmembrane domain; and (c) a 1-bp insertion in the polyadenylic acid microsatellite region resulting in a reading frameshift. In addition, six cases (25%) exhibited a common bp substitution (C-->T at nucleotide 1322) in both tumor and patient-matched normal tissues. This is the first report of such TbetaR-II mutations in primary human ovarian carcinomas. Immunohistochemical analysis demonstrated a loss of expression of TbetaR-II in 5 of 22 available tumors (23%; 4 of which also had mutations in the coding region) and decreased expression of TbetaR-II in 10 of 22 available tumors (44%; 1 of which had a mutation in the coding region). Thus, the loss or decreased expression of TbetaR-II seems to be a common event in sporadic ovarian carcinomas, and mutational inactivation, due to either frameshift mutations in the polyadenylic acid microsatellite region or point mutations in conserved functional domains, is one mechanism by which this occurs.

Adult↗

PubMed1998

Mutation analysis using the restriction site mutation (RSM) assay.

The restriction site mutation (RSM) assay (see Steingrimsdottir et al. [H. Steingrimsdottir, D. Beare, J. Cole, J.F.M. Leal, T. Kostic, J. Lopez-Barea, G. Dorado, A.R. Lehmann, Development of new molecular procedures for the detection of genetic alteration in man, Mutat. Res. 353 (1996) pp. 109-121] for a review) has been developed as a genotypic mutation detection system capable of identifying mutations occurring in restriction enzyme sites of genomic DNA. Here we will report the steps taken to overcome some of the initial problems of the assay, namely the lack of quantitative data and limited sensitivity, the aim being to achieve a methodology suitable for the study of low dose chemical exposures. Quantitative data was achieved in the RSM assay by the inclusion of an internal standard molecule in the PCR amplification stage, thus allowing the calculation of both spontaneous and induced mutation frequencies. The sensitivity of the assay was increased through the discovery that intron sequences of genomic DNA accumulated more mutations in vivo compared to the exons, presumably due to differential selective pressure within genes [G.J.S. Jenkins, I.deG. Mitchell, J.M. Parry, Enhanced restriction site mutation (RSM) analysis of 1, 2-dimethylhydrazine-induced mutations, using endogenous p53 intron sequences, Mutagenesis 12 (1997) pp. 117-123]. This increased sensitivity was examined by applying the RSM assay to analyse the persistence of N-ethyl-N-nitrosourea (ENU)-induced mutations in mice testes. Germ line mutations were sought in testes DNA 3, 10 and 100 days after ENU treatment. Mutations were detected in exons and especially intron regions, the intron mutations were more persistent, still being detected 100 days post-chemical treatment. Assignment of these mutations as ENU induced was complicated in some cases where the spontaneous mutation level was high. This theme of mutation persistence was further investigated by studying the presence of 4-nitroquinoline-1-oxide (4-NQO)-induced DNA mutations in vitro. This study also analysed the relationship between DNA adduct formation and DNA mutation induction by the concurrent RSM analysis and 32P post-labelling analysis of 4-NQO treated human fibroblasts. The results demonstrated that early DNA mutations detected 4 days post-treatment by the RSM assay were probably ex vivo mutations induced by Taq polymerase misincorporation of 4-NQO adducted DNA, due to the maximum levels of 4-NQO adducts being present at this time point. A later mutational peak, after the adduct level had declined, was assumed to be due to DNA sequence changes produced in the fibroblasts by the in vivo processing of DNA adducts.

4-Nitroquinoline-1-oxide↗

PubMed1998

Conversion of neuronal growth cone responses from repulsion to attraction by cyclic nucleotides.

Nerve growth is regulated by attractive and repulsive factors in the nervous system. Microscopic gradients of Collapsin-1/Semaphorin III/D (Sema III) and myelin-associated glycoprotein trigger repulsive turning responses by growth cones of cultured Xenopus spinal neurons; the repulsion can be converted to attraction by pharmacological activation of the guanosine 3',5'-monophosphate (cGMP) and adenosine 3',5'-monophosphate signaling pathways, respectively. Sema III also causes the collapse of cultured rat sensory growth cones, which can be inhibited by activation of the cGMP pathway. Thus cyclic nucleotides can regulate growth cone behaviors and may be targets for designing treatments to alleviate the inhibition of nerve regeneration by repulsive factors.

Animals↗

PubMed1998

Biochemical separations by continuous-bed chromatography.

Innovations in column-packing media for biomolecule purification have progressed from large spherical, porous polysaccharide beads to advanced polymeric supports. Continuous-bed technology is a radical new technology for chromatography based on the polymerization of advanced monomers and ionomers directly in the chromatographic column. The polymer chains form aggregates which coalesce into a dense, homogeneous network of interconnected nodules consisting of microparticles with an average diameter of 3000 A. The voids or channels between the nodules are large enough to permit a high hydrodynamic flow. Due to the high cross-linking of the polymer matrix, the surface of each nodule is nonporous yet the polymeric microparticles provide a very large surface area for high binding capacity. This paper will demonstrate the properties and advantages of using a continuous bed support for high resolution biomolecule separations at high flow-rates without sacrificing capacity.

Animals↗

PubMed1998

OCI-5/GPC3, a glypican encoded by a gene that is mutated in the Simpson-Golabi-Behmel overgrowth syndrome, induces apoptosis in a cell line-specific manner.

OCI-5/GPC3 is a member of the glypican family. Glypicans are heparan sulfate proteoglycans that are bound to the cell surface through a glycosyl-phosphatidylinositol anchor. It has recently been shown that the OCI-5/GPC3 gene is mutated in patients with the Simpson-Golabi-Behmel Syndrome (SGBS), an X-linked disorder characterized by pre- and postnatal overgrowth and various visceral and skeletal dysmorphisms. Some of these dysmorphisms could be the result of deficient growth inhibition or apoptosis in certain cell types during development. Here we present evidence indicating that OCI-5/GPC3 induces apoptosis in cell lines derived from mesothelioma (II14) and breast cancer (MCF-7). This induction, however, is cell line specific since it is not observed in NIH 3T3 fibroblasts or HT-29 colorectal tumor cells. We also show that the apoptosis-inducing activity in II14 and MCF-7 cells requires the anchoring of OCI-5/GPC3 to the cell membrane. The glycosaminoglycan chains, on the other hand, are not required. MCF-7 cells can be rescued from OCI-5/GPC3-induced cell death by insulin-like growth factor 2. This factor has been implicated in Beckwith-Wiedemann, an overgrowth syndrome that has many similarities with SGBS. The discovery that OCI-5/GPC3 is able to induce apoptosis in a cell line- specific manner provides an insight into the mechanism that, at least in part, is responsible for the phenotype of SGBS patients.

3T3 Cells↗

PubMed1998

X-ray crystal structure of the yeast Kar3 motor domain complexed with Mg.ADP to 2.3 A resolution.

The kinesin family of motor proteins, which contain a conserved motor domain of approximately 350 amino acids, generate movement against microtubules. Over 90 members of this family have been identified, including motors that move toward the minus or plus end of microtubules. The Kar3 protein from Saccharomyces cerevisiae is a minus end-directed kinesin family member that is involved in both nuclear fusion, or karyogamy, and mitosis. The Kar3 protein is 729 residues in length with the motor domain located in the C-terminal 347 residues. Recently, the three-dimensional structures of two kinesin family members have been reported. These structures include the motor domains of the plus end-directed kinesin heavy chain [Kull, F. J., et al. (1996) Nature 380, 550-555] and the minus end-directed Ncd [Sablin, E. P., et al. (1996) Nature 380, 555-559]. We now report the structure of the Kar3 protein complexed with Mg.ADP obtained from crystallographic data to 2.3 A. The structure is similar to those of the earlier kinesin family members, but shows differences as well, most notably in the length of helix alpha 4, a helix which is believed to be involved in conformational changes during the hydrolysis cycle.

Adenosine Diphosphate↗

PubMed1998

Acetylcholinesterase enhances neurite growth and synapse development through alternative contributions of its hydrolytic capacity, core protein, and variable C termini.

Accumulated indirect evidence suggests nerve growth-promoting activities for acetylcholinesterase (AChE). To determine unequivocally whether such activities exist, whether they are related to the capacities of this enzyme to hydrolyze acetylcholine and enhance synapse development, and whether they are associated with alternative splicing variants of AChEmRNA, we used four recombinant human AChEDNA vectors. When Xenopus laevis embryos were injected with a vector expressing the synapse-characteristic human AChE-E6, which contains the exon 6-encoded C terminus, cultured spinal neurons expressing this enzyme grew threefold faster than co-cultured control neurons. Similar enhancement occurred in neurons expressing an insertion-inactivated human AChE-E6-IN protein, containing the same C terminus, and displaying indistinguishable immunochemical and electrophoretic migration properties from AChE-E6, but incapable of hydrolyzing acetylcholine. In contrast, the nonsynaptic secretory human AChE-I4, which contains the pseudointron 4-derived C terminus, did not affect neurite growth. Moreover, no growth promotion occurred in neurons expressing the catalytically active C-terminally truncated human AChE-E4, demonstrating a dominant role for the E6-derived C terminus in neurite extension. Also, AChE-E6 was the only active enzyme variant to be associated with Xenopus membranes. However, postsynaptic length measurements demonstrated that both AChE-E6 and AChE-E4 enhanced the development of neuromuscular junctions in vivo, unlike the catalytically inert AChE-E6-IN and the nonsynaptic AChE-I4. These findings demonstrate an evolutionarily conserved synaptogenic activity for AChE that depends on its hydrolytic capacity but not on its membrane association. Moreover, this synaptogenic effect differs from the growth-promoting activity of AChE, which is unrelated to its hydrolytic capacity yet depends on its exon 6-mediated membrane association.

Acetylcholinesterase↗

PubMed1998

Clinical and echocardiographic outcomes of aortic intramural hemorrhage compared with acute aortic dissection.

Aortic intramural hemorrhage (IMH), which presents clinical manifestations identical to those of acute aortic dissection, is different from aortic dissection in terms of the absence of intimal tear and communication of blood flow between the true and false lumen. This study was conducted for the purpose of diagnosing IMH by transesophageal echocardiography (TEE) prospectively and comparing the clinical and echocardiographic outcome of IMH with aortic dissection. Between August 1991 and November 1996, 27 IMHs and 73 acute aortic dissections were diagnosed using TEE in 202 consecutive patients with suspected aortic dissections. The TEE diagnoses of IMH and aortic dissection were initially compared with computed tomography and magnetic resonance imaging and later confirmed by operative findings (n = 37) or follow-up changes (n = 12). In the 49 patients whose diagnosis was confirmed by operation or follow-up changes, the sensitivity and specificity of TEE for the diagnosis of IMH were 27 of 27 (100%) and 20 of 22 (91%), respectively. There were 11 deaths in 73 patients (15%) from acute aortic dissection and 1 death in 27 patients (4%) from IMH during a follow-up of 1.7+/-1.5 years (p = NS). Stanford classification and types of treatment were not related to death in both groups. Complications developed less often in patients with IMH (3 of 27) than in those with acute aortic dissection (24 of 73), and no death occurred in patients with uncomplicated IMH who were medically treated. A follow-up imaging study of 12 IMH patients showed complete resolution in 8, regression in 3, and progression in 1 patient. TEE is accurate in the diagnosis of IMH and IMH has a lower incidence of complications than aortic dissection because of the absence of intimal tear and communication of blood flow in the false lumen.

Acute Disease↗

PubMed1998

Localization of two forms of phospholipase C-beta1, a and b, in C6Bu-1 cells.

Phospholipase C-beta1 (PLC-beta1), one of the PLC-beta isozymes, exists as two immunologically distinguishable polypeptides of 150 (PLC-beta1a) and 140 kDa (PLC-beta1b) which are encoded in two distinct transcripts and generated by alternative splicing of a single gene. In this study, the subcellular localization of the two phospholipases C-beta1 proteins was examined in rat C6Bu-1 glioma cells using immunological techniques. Immunoblot analysis revealed that the two forms of PLC-beta1 were detectable in both cytosolic and nuclear fractions. PLC-beta1a appeared to be located preferentially in the cytosol, whereas PLC-beta1b was found predominantly in the nuclei of C6Bu-1 cells. Immunocytochemical experiments confirmed the differential localization of the two PLC-beta1 species in C6Bu-1 cells. These results suggest that the two PLC-beta1 proteins may have different physiological roles in the cell.

Alternative Splicing↗