Biomedical subjects
X L Zhou
Publications and source records attributed to X L Zhou.
[A study of paeonol injection on immune functions in rats].
Paeonol is the main effective component of the traditional Chinese medicine, Paeonia suffroticosa. Paeonol has some therapeutic effects in resisting many species of bacteria and fungi. But the mechanism of such effects is still unclear. We used low dosage of paeonol injection (10-15 mg/kg) to observe its effect on the functions of the immune system of the Wistar's rats. The methods include peripheral blood ANAE+ lymphocytes (PBAL), leucocyte migrating inhibition factors (LMIF), specific rosette forming cells (SRFC) of spleen, and bacteria phagocytosis of polymorphonuclear neutrophil (BPP). The results showed that paeonol could enhance specific cellular immunity by raising the percentage of the PBAL (P < 0.01) and the release of LMIF (P < 0.01). Paeonol could also increase the BPP (P < 0.01). On the other hand, although it could increase the percentage of SRFC of the spleen, such an effect showed no significant difference (P > 0.1). These enhancing effects of the specific cellular immunity and the nonspecific phagocytosis functions of the immune system might be one of the mechanisms of the antibacterial effects of paeonol. The possible modulating activity of paeonol may develop a new applied field in clinical practice.
[Clinical analysis of the relation between maternal body weight and high risk factors during pregnancy and delivery].
The incidence of pregnancy induced hypertension (PIH), prolonged pregnancy, prolonged labor, macrosomia and the rate of operative delivery were analysed in 76 overweight women and in 436 women with normal body weight admitted at the same period to the hospital. The results showed that the occurrence of risk factors mentioned above was significantly higher in the overweight group, particularly in those with excessive weight gain during pregnancy than that of normal weight group (P < 0.001-0.05). To reduce high risk pregnancy, operative delivery, perinatal mortality and morbidity in overweight women especially associated with excessive weight gain during pregnancy the importance of perinatal care with nutritional advice is evident.
A mechanosensitive ion channel in Schizosaccharomyces pombe.
Protoplast protuberances (blebs) of Schizosaccharomyces pombe were examined using the patch-clamp technique. In addition to several voltage-gated ion channels, we encountered the activities of a mechanosensitive ion channel with a conductance of 180 pS. Microscopic currents of one or two units were observed in some excised patches and ensemble currents of several tens of units were observed in all blebs examined in whole-bleb configuration. This channel opens at pressures of cm Hg applied to whole blebs and it passes cations, including Ca2+. It is inactivated by membrane depolarizations and blocked by Gd3+. We discuss the possible functions of such a channel, including its activation upon cell cycle dependent cytoskeletal reorganizations.
A mechanosensitive channel in whole cells and in membrane patches of the fungus Uromyces.
Bean leaf stomata provide a topographical signal that induces germlings of the phytopathogen Uromyces appendiculatus to develop specialized infection structures. Protoplasts from germ tubes of this fungus, when examined with patch-clamp electrodes, displayed the activities of a 600-picosiemen mechanosensitive ion channel. This channel passes a variety of cations, including Ca2+, and is blocked by Gd3+ at 50 micromolar. This channel could transduce the membrane stress induced by the leaf topography into an influx of ions, including Ca2+, that may trigger differentiation.
[Application of liposuction and its clinical significance].
300 liposuction patients involving 444 anatomical areas are reported in this paper. The clinical significance of the applied anatomy and the comparison between groups are analyzed. 1. The distribution of the liposuction areas. 2. The distribution of blood vessels in the abdominal wall, buttocks and thighs and its relation to the volume of fat removed as well as blood loss. The blood vessels are so abundant in the abdominal wall that the blood loss is larger than that in the buttocks and thighs in the operation. According to the anatomical characteristics of distribution of the blood vessels, the authors pointed out a few "relatively forbidden areas". In group 2 we intentionally avoided doing liposuction in these areas. The results showed that the blood loss was less than that in group 1 and that the volume of fat removed could obviously be increased. 3. The characteristics of liposuction in severe obesity or in patients over 90kg body weight: The aspirate volume is big; the blood versus fat ratio is low. So it is possible to increase the aspirate volume. The elasticity of skin of the abdominal wall is very high. It is not necessary to remove skin in very obese patients with abdominal dermatochalasis.
A Monte Carlo investigation of the dosimetric properties of monoenergetic neutron beams for neutron capture therapy.
A Monte Carlo simulation study has been carried out to investigate the suitability of neutron beams of various energies for therapeutic efficacy in boron neutron capture therapy. The dosimetric properties of unidirectional, monoenergetic neutron beams of varying diameters in two different phantoms (a right-circular cylinder and an ellipsoid) made of brain-equivalent material were examined. The source diameter was varied from 0.0 to 20.0 cm; neutron energies ranged from 0.025 eV up to 800 keV, the maximum neutron energy generated by a tandem cascade accelerator using 2.5-MeV protons in a 7Li(p,n)7Be reaction. Such a device is currently under investigation for use as a neutron source for boron neutron capture therapy. The simulation studies indicate that the maximum effective treatment depth (advantage depth) in the brain is 10.0 cm and is obtainable with a 10-keV neutron beam. A useful range of energies, defined as those neutron energies capable of effectively treating to a depth of 7 cm in brain tissue, is found to be 4.0 eV to 40.0 keV. Beam size is shown not to affect advantage depth as long as the entire phantom volume is used in determining this depth. Dose distribution in directions parallel to and perpendicular to the beam direction are shown to illustrate this phenomenon graphically as well as to illustrate the differences in advantage depth and advantage ratio and the contribution of individual dose components to tumor dose caused by the geometric differences in phantom shape.
Yeast K1 killer toxin forms ion channels in sensitive yeast spheroplasts and in artificial liposomes.
The patch-clamp technique was used to examine the plasma membranes of sensitive yeast spheroplasts exposed to partially purified killer toxin preparations. Asolectin liposomes in which the toxin was incorporated were also examined. Excised inside-out patches from these preparations often revealed at 118 pS conductance appearing in pairs. The current through this conductance flickered rapidly among three states: dwelling mostly at the unit-open state, less frequently at the two-unit-open state, and more rarely at the closed state. Membrane voltages from -80 to 80 mV had little influence on the opening probability. The current reversed near the equilibrium potential of K+ in asymmetric KCl solutions and also reversed near O mV at symmetric NaCl vs. KCl solutions. The two levels of the conductance were likely due to the toxin protein, as treatment of spheroplasts or liposomes with extracellular protein preparations from isogenic yeasts deleted for the toxin gene gave no such conductance levels. These results show that in vivo the killer-toxin fraction can form a cation channel that seldom closes regardless of membrane voltage. We suggest that this channel causes the death of sensitive yeast cells.
[Comparative study on protein components of ouabain resistant mutant and wild cells of Chinese hamster V79 cell line by two-dimensional gel electrophoresis].
In the sense of gene expression, the primary and direct change in mutant cells should be involved in the protein component. Two-dimensional polyacrylamide gel electrophoresis has been used to compare the protein components of ouabain resistant mutant cells (ouaR) and sensitive wild type cells (ouaS) of chinese hamster lung cell line V79. The procedure is based on O'Farrell's method and we have made some modifications. In order to make the study reliable, we took twenty polypeptide spots as a reference marker. These marker spots could always be reproduced in a series of parallel experiments with both mutant and wild cells. In addition, these markers covered different small areas, representing different isoelectric point (pI) and molecular weight (MW) on the electrophoretogram. With reference to these marker spots, some polypeptide spots showed variations in their position, size and density. It is notable that the changes appeared in the small area 4 (pI/MW:5.0/28-30kd) and the small area (pI/MW:6.3/39kd) is highly reproducible and significant, so that these changes might be specific to ouabain resistant mutant of V79 cells. Since the level of genetic polymorphism of mammalian cells on two-dimensional gel electrophoresis is quite low, these specific changes might reflect the differences in gene structure and expression. This primary study should enhance the usefulness of two-dimensional gel electrophoresis for mutagenesis research with cultured mammalian somatic cells.
A mechanosensitive ion channel in the yeast plasma membrane.
Mechanosensitive ion channels use mechanical energy to gate the dissipation of electrochemical gradients across cell membranes. This function is fundamental to physiological processes such as hearing and touch. In electrophysiological studies of ion channels in the plasma membrane of the yeast Saccharomyces cerevisiae, channels were observed that were activated by, and adapted to, stretching of the membrane. Adaptation of channel activity to mechanical stimuli was voltage-dependent. Because these mechanosensitive channels pass both cations and anions, they may play a role in turgor regulation in this walled organism.
[Purification of HMGs and HP1 from Beijing duck and their effects on nuclei transcription activity in vitro].
Explore the source record for details and available documents.
[Single ion channel recording of biomembranes and some new advances in the study of calcium channels].
Explore the source record for details and available documents.
[Seven years' follow-up observation on the treatment of schistosomiasis with pyquiton].
Explore the source record for details and available documents.
[An evaluation of simultaneous blepharoplasty and correction of saddle nose].
Explore the source record for details and available documents.
[Delayed addition of some Chinese herb drugs in making decoctions].
Explore the source record for details and available documents.
[Treatment of severe twisting deformity of the burned hand].
Explore the source record for details and available documents.
[Anti-inflammatory effect of Bacillus subtilis neutral protease].
Explore the source record for details and available documents.
[Comparative study on various dose schedules of praziquantel in the treatment of schistosomiasis japonica].
Explore the source record for details and available documents.