Objective To investigate the distribution of free Ca 2+ and characterization of Ca 2+ channel in the cultured 11～15 week human embryonic retina. Methods The cells from 11～15 week embryonic retina were dissociated enzymatically and cultured on coated cover slides. Three weeks later, Fluo3, a Ca 2+ indicator, was added in Ca 2+ containing or no Ca 2+ Hepes buffer and incubated with retinal cells for 30 min, meanwhile with or without verapamil, perdipine, or dexamethasone adding. Ca 2+ staining and Ca 2+ transit before and after 10 ?mol/L or 50 ?mol/L KCl stimulation was observed and recorded using Zeiss LM510 confocal laser scanning microscopy. Results In response to K + exposure, a rapid rise of free Ca 2+ in cytoplasma and nuclei of neuron and glial cell was observed, but was repressed with the treatment of verapamil, perdipine, or dexamethasone. The obvious Ca 2+ influx from cytoplasma into nuclei was observed even in the absence of external Ca 2+ . Conclusion L type Ca 2+ channel was expressed and functionally matured in the cultured early stage human embryonic retina.

The diameters and projection area of the articular surfaces, contributed to the formation of the sacroiliac joint, were determined on 50 sets of pelvic bones with image analysing apparatus.By drawing a line connecting the most anterior point of the prominence to the deepest point of the posterior incisure, the articular surface may be divided into a superior and an inferior portions. The inferior portion was larger than the superior portion. Each portion of the articular surface on the ilium is slightly larger than that on the sacrum.In order to explore the relationship between the form of the articular surface and its function in transmitting the gravity of the human body, the stress of the neighbouring area near the anterior margin of the articular surface was determined. Moreover, the bony architecture on the cross section passing through the articular surface was observed. It suggests that the strain in the neighbouring area was in linear equation with the gravity loaded on the spinal column. The strongest stress was determined at the anterior margin of the anterior prominence and the thickness of the cortex lying on the relevant bones appears most obvious at the same sites. These results further improve that the bony architecture was consistent with the strain in bearing the body weight. Besides, the form of the articular surface was also adapted to its function.

The human venous valve of the brachial,femoral and long saphenous veins wereexamined with light,transmission and scanning electron microscopy.The observationshows that the venous valve is composed of three functional layers covered withendothelium on both surfaces.A loosely structured layer is located underlying theendothelium.A network mainly containing randomly oriented elastic fibers was foundnear the side towards the lumen.To the side towards the venous wall,there is adense layer composed of eircumferentially and transversly oriented collagen bundles.Some smooth muscle cells extend from the wall of the vein to the base of thevenous valve.The elastic fibers and smooth muscle cells together with the collagenfibers contribute to the mechanical load-bearing performance of the valve and to thepassive closing and openning mechanism.In addition,the smooth muscle cells mightplay an active role in the normal functioning of the valve.The scanning and transmission electron microscopy of venous valve showdifferent arrangement of the endothelium.On the surface of the valve next to the wallof the vein,the endothelial cells are transversely arranged,while on the othersurface over which the current of blood flows,the cells are longitudinally arrangedin the direction of the current.These accord with the role of fluid mechanics.12 normal venous valves were tested by universal testing instrument (Instrontype 1122).The mean value of the maximum tension of the valve is 1 N.Theaverage value of the tensile ultimate strength is 10N/mm~2.

OBJECTIVETo study the influence of Ureaplasma urealyticum (Uu) infection on the sperm-egg binding associated molecule, sulfogalactosylglycerolipid (SGG).

METHODSEpididymal sperm was collected from adult mice. The sperm suspension was randomly divided into 4 groups: Uu group (coincubated with Uu suspension), medium group (coincubated with Uu medium), normal group and PRS group. The indirect immunofluorescence technique was used to localize SGG on the sperm membrane and to observe the influence of Uu on SGG.

RESULTSIn the epididymal sperm, SGG was localized to the head plasma membrane overlaying the acrosomal region. The SGG-positive rate of the sperm coincubated with Uu medium was 82.0%, while that of the sperm coincubated with Uu suspension was reduced to 39.0% (P = 0.001).

CONCLUSIONUu can adhere to the sperm surface. SGG might be a membrane receptor on the sperm surface for Uu infection of the mammalian male genital tract. The blockage of SGG by Uu might be one of the molecular mechanisms correlative to male infertility induced by Uu infection.

Animals ; Cell Membrane ; metabolism ; Galactolipids ; biosynthesis ; Infertility, Male ; etiology ; Male ; Mice ; Mice, Inbred BALB C ; Random Allocation ; Sperm-Ovum Interactions ; physiology ; Spermatozoa ; metabolism ; Ureaplasma Infections ; complications ; metabolism ; Ureaplasma urealyticum