Biomedical subjects
Publications and source records attributed to Y Zhou.
The antioxidative effect of more than 50 ethanol extracts of Chinese drugs were studied on the air oxidation of linoleic acid. Several ethanol extracts such as Glycyrrhiza uralensis, Magnolia officinalis and Zingiber officinale etc., were found having stronger antioxidative effect.
Erythropoietin (EPO) is a glycoprotein hormone secreted by human kidney cells. Human EPO was induced from human embryo kidney cells, isolated and purified from medium by biochemical method in our laboratory. The hypoproliferative anemia in chronic renal failure (CRF) has been assumed to be the result of decreased EPO production by the damaged kidney and of the shortening of the survival of erythrocytes. In this study, CRF anemia was formed 9 weeks after the removal of five-sixths of the renal mass of rats. These anemic rats were divided into 6 groups: treated with different dosages of EPO or physiological saline. The results indicate that EPO has apparent effects on anemia in rats with CRF. It may stimulate erythropoiesis and improve the anemia state of rats with CRF. Hematological parameters (RBC, Hb, PLT, Ht and Rt) may be reverted to normal levels (P less than 0.001). The level of BUN and Cr were significantly decreased. The optimum dose of EPO was 1000 U/kg. All these results show that injection of EPO has therapeutic effect on anemia in rats with CRF. EPO showed no effect on normal rats.
The protoplast fusion between Candida guilliermondii S208 (Arg-) and Saccharomyces cerevisiae 314 was induced by three pulses (18kV/cm, 10 microseconds duration) applied at an interval of 1 s with the model GH-401 Electric Induced Gene Transfer/Cell Fusion System. The frequency of appearance of prototrophic hybrids was 3.6 x 10(-3). Stable fusion products were obtained after continual subculture over 20 times on selected and unselected media. Comparative studies showed that the fusion products were real hybrids of both parents. Two fustants, F-106 and F-308, could ferment both D-xylose and cellobiose to ethanol. The ethanol production of F-106 in the media containing 2% D-xylose or 2% cellobiose were 3.1g/l and 1.05g/l, respectively. The ethanol production of F-308 in the above media were 0.2g/l and 2.8g/l, respectively.
From December of 1986 through February of 1990, digital subtraction angiography was performed on 156 patients, and specific diagnoses of congenital heart disease were made on the basis of information gathered by this imaging technique, supplemented by the physical examination. No other imaging techniques were used, for this was a prospective study designed to determine the accuracy of digital subtraction angiography alone in the diagnosis of congenital heart disease. When 80 of these 156 patients underwent subsequent operation, 75 were shown to have been diagnosed correctly, for an accuracy rate of 93.75%. Two patients died, for a mortality rate of 2.5%. The diagnostic value of digital subtraction angiography is discussed, as well as the compensative management of its artifacts.
The shedan chuangbei oral liquid in low sucrose content by adding stevioside not only reduces the cost of preparation but has better stability in quality and clarity. Qualitative analysis, TLC and determination of alkaloids all show correspondence in composition between the original drug and the new preparation.
Opiates modulate a variety of immune responses by peripheral blood mononuclear cells (PBMC). In the present study, we investigated the effect of morphine on the release of several cytokines upon stimulation with mitogens. An interleukin (IL)-4-dependent HT-2 cell proliferation assay was used to quantify transforming growth factor-beta (TGF-beta). IL-6 and tumor necrosis factor-alpha (TNF-alpha) were measured by enzyme-linked immunosorbent assays. Morphine (1 pM and 10 nM) alone did not significantly modulate the release of TGF-beta, IL-6 or TNF-alpha. Upon stimulation with lipopolysaccharide and phytohemagglutinin, PBMC released more (P less than .01) TGF-beta, IL-6 and TNF-alpha than unstimulated PBMC. Exposure of PBMC to morphine (1 pM) for 24 hr substantially amplified (P less than .05) the release of TGF-beta in the following 24 hr incubation period. Morphine did not alter the release of immunodetectable IL-6 or TNF-alpha from stimulated cells. The amplifying effect of morphine on the release of TGF-beta was mediated through a naloxone-sensitive mechanism. Given the fact that TGF-beta has a potent immunosuppressive effect, morphine-potentiated release of TGF-beta from PBMC may be involved in the immunomodulatory activity ascribed to morphine.
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The principle of an optical molecular sensor using ion-exchanged buried planar waveguides in glass has been demonstrated. We have shown both theoretically and experimentally that the intensity of the peak evanescent fluorescence can be increased by several orders of magnitude with the use of an index-matching material. The method of differential measurement has been used to improve the differentiation between specific and non-specific binding. We used h-IgG (human immunoglobulin G) as the immobilized antibody on the surface of the waveguide and protein A-FITC (fluorescein isothiocyanate) as the fluorescently labelled antigen or anti-antibody to be detected, and have shown that a concentration of protein A as low as 24 nM can easily be detected.
There is a shift in buffer pH routinely encountered during electrophoresis. If one is running glyoxylated RNA on agarose gels, this pH shift can have potentially detrimental effects on experimental objectives if the shift is allowed to proceed unabated; this is due to the fact that the RNA will deglyoxylate if the pH is allowed to rise above 8.0. In order to counteract the shift, the buffer may be continuously recirculated or totally replaced at predetermined intervals. Because constant recirculation may be technically bothersome to achieve and because repeated total buffer replacement may require large amounts of highly purified water, we have studied (a) the time course of the pH change encountered during the electrophoretic process and (b) whether or not simple manual mixing of the buffer system at specific intervals was sufficient to maintain pH within acceptable bounds. We found that, under the given conditions, the cathode pH had nearly reached 8.0 at 25 min and had soared to 10.5 at 40 min. We further found that manual mixing at 20-min intervals not only prevented the cathode pH from rising above 7.8, but also restored the buffer to its initial pH.
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Roots, root cortices and root corks from 6 species of Boraginaceae are used as zicao in commercial crude drugs. This paper reports the determination of naphthaquinone pigments (such as total pigments, beta, beta-dimethylacryshikonin, acetylshikonin and shikonin) in 12 samples of 6 plants. The quality of various drugs was evaluated by determining the contents of the above principles.
A new chiral derivatizing reagent (s)-alpha-methoxybenzyl isocyanate (MIB) was prepared from (s)-(+)-mandelic acid with a practical method, and its ability of liquid chromatographic resolution for drug enantiomers by pre-column chiral derivatization was evaluated with racemic amphetamine and mexiletine as well as phenylpropanol. The operation is simple and rapid. Separation is good for the amine isomers, but poor for alcohols and extensive work remains to be done. The solution of derivatization was directly injected into the chromatograph. Conventional silica gel column was used with light petroleum as the mobile phase.
By recombinant DNA technology, the N-terminal of the beta-protein encoding region of plasmid pUB110 is fused with the structure gene of alpha-amylase from Bacillus licheniformis. This gene fusion is called beta Amy. It is able to transcribe and translate in phase. Protein fusion can be secreted into the medium mediated by beta-signal peptide. The efficiency of secretion is about 10% of the synthesized pre-alpha-amylase. By comparing the secretion capacities and analysing the restriction sites on beta-Amy genes and the molecular weights of the mature alpha-amylase secreted by B. subtilis harbouring different plasmids, it is indicated in vivo that the recognition and cleavage sequence for signal peptidase I of B. subtilis is Ala-Ala-Ala Ala. The results also indicate that the secretion of the alpha-amylase in B. subtilis is in accordance with the post-translational transportation mode.
In this paper, hemodynamic changes of 254 subjects were observed by using impedance cardiogram in a double-blind control method. The subjects were divided into 5 groups: heart-asthenia syndrome (98 cases), lung-asthenia syndrome (23 cases), spleen-asthenia syndrome (23 cases), kidney-asthenia syndrome (10 cases) and normal group (100 cases). The results showed that hemodynamic abnormalities occurred in the patients with heart-asthenia syndrome only, the changed regularities were that deficiency of both vital energy and Yin greater than deficiency of heart-Yang greater than deficiency of heart-energy greater than deficiency of heart-Yin. When stroke volume (SV), cardiac output (CO), cardiac index (CI), stroke volume index (SVI), heather index (HI), vascular compliance (C) and ejection fraction (EF) were decreased and total peripheral resistance (TPR) and systolic time interval (STI) were increased, the signs and heart-asthenia syndrome could be found in clinical practice. In conclusion, the above parameters had certain diagnostic value for heart-asthenia syndrome and could be subjective quantitative indices for evaluating effects of treating the heart-asthenia syndrome.