Prognostic indicators in centroblastic-centrocytic lymphoma.

The prognostic importance of ploidy and proliferative index (%S + G2) assessed by flow cytometry, mitotic and centroblast counts, and histological growth pattern were evaluated in biopsy specimens taken before treatment from 60 cases of centroblastic-centrocytic non-Hodgkin's lymphoma. Cases with a high proliferative index (greater than or equal to 18%) or DNA aneuploidy showed significantly poorer survival than those with a low proliferative index (less than 18%). A high mitotic count was also associated with a poor prognosis. On multiple regression analysis the flow cytometric assessments and mitotic counts were significant predictors of survival. Assessments of proliferative activity clearly have prognostic potential in centroblastic-centrocytic lymphoma and may permit more accurate characterisation of individual tumours.     

Role of chemotaxis in the association of motile bacteria with intestinal mucosa: in vitro studies.

Various Sephadex G-15 fractions of pepsin-digested mucosal extract inhibited the in vitro association of cholera vibrios with mucosal slices. Inhibitory activity paralleled the taxin activity of the fractions for these bacteria. This supports the theory that inhibition of mucosal association by pepsin-digested mucosal scrapings was due to the blocking of taxin receptors on the bacterial surface. Nonchemotactic mutants were significantly less efficient than the chemotactic parent or revertant strains in associating with mucosal slices in vitro. Control experiments in which filter paper disks replaced the mucosal slices showed a comparable extent of association of chemotactic and nonchemotactic vibrios with this material. Histological studies indicated that vibrios associated predominantly with the mucus gel of the intestinal slices rather than with the mucosal epithelium or the serosal surface. Intestinal slices attracted chemotactic vibrios even after prolonged washing, suggesting continuous production of the taxin by the tissue. Inert polystyrene particles 1.1 micrometers in diameter penetrated the mucus gel of intestinal slices very poorly, but nevertheless could be detected in low numbers in the deep intervillous spaces within 15 min. In contrast, chemotactic vibrios reached the deep intervillous spaces in significantly higher numbers, whereas motile, non-chemotactic vibrios reacted like the inert particles. It is concluded that mucus gel represents a partial barrier to the penetration of particles of bacterial size and that this barrier can be invaded efficiently by motile bacteria, but only when their locomotion is guided by chemotactic stimuli.     

The use of linked DNA polymorphisms for genotype prediction in families with Duchenne muscular dystrophy.

Two DNA restriction fragment length polymorphisms show genetic linkage to the Duchenne muscular dystrophy locus on the short arm of the X chromosome. Examples are given of families in which these polymorphisms can be used in the prediction of genotype for this disorder.     

Changes in the heparin neutralising activity of platelet poor plasma after immunisation.

Acute myocardial disease, which may be associated with abnormal platelet activity, has been reported after routine immunisation. Thirty-two army apprentices undergoing immunisation were studied for changes in the heparin neutralising activity (HNA) of platelet poor plasma. HNA increased after immunisation. This increase in HNA may represent an increase in platelet activation but may also relate to changes in acute phase proteins. These changes were not observed in elderly subjects undergoing immunisation with influenza vaccine.     

Expression of superoxide dismutase and xanthine oxidase in myometrium, fetal membranes and placenta during normal human pregnancy and parturition

Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.      

Hydrosalpinges adversely affect markers of endometrial receptivity

While in-vitro fertilization (IVF) was initially developed in women with tubal factor infertility, recent clinical studies have suggested that the presence of hydrosalpinges lowers implantation and pregnancy rates. We postulated that these hydrosalpinges cause impaired endometrial receptivity. A total of 103 women with hydrosalpinges were prospectively evaluated, and compared with 55 infertile and 44 fertile controls. All women had endometrial biopsies during the window of implantation, analysed by conventional histological criteria, and also stained for three integrin markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha vbeta3). Women with hydrosalpinges (cases) expressed significantly less of the alpha vbeta3 integrin compared with controls. There was no difference in expression of alpha1beta1 or alpha4beta1 among groups. A significantly greater number of cases had out of phase histology and missing alpha vbeta3 (type I defects) and absent integrin expression despite normal histological maturation (type II) defects, compared with controls. Of 20 women with impaired endometrial receptivity who were also biopsied after hydrosalpinx surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven percent of type I and 57% of type II defects were corrected postoperatively. Using markers of endometrial receptivity, this study demonstrates that inflammatory hydrosalpinges have an adverse effect on endometrial receptivity, which in some cases may be overcome by surgical treatment of the hydrosalpinx.      

大鼠视皮质胼胝体轴突的生后发育和形态──生物素结合的葡聚糖胺顺行示踪法研究

采用生物素结合的葡聚糖胺顺行示踪法研究了大鼠视皮质主要胼胝体投射区即１７／１８ａ交界区胼胝体轴突的生后发育和形态。在生后５天时，此交界区胼胝体轴突从白质向灰质Ⅰ层垂直生长，在灰质内仅有极少量的侧支抽芽。至生后１３天时，皮质Ⅰ层最先出现致密的由胼胝体轴突终支组成的终末丛。到生后１７天时，类似的终末丛也见于皮质Ⅱ／Ⅲ，Ⅴ和Ⅵ层，这种分布型式与成年大鼠者相似。以上结果表明，绝大部分胼胝体轴突首先生长到达Ⅰ层并先在Ⅰ层发出终支，然后再在其它皮质层发出侧支及终支，因而提示皮质Ⅰ层在胼胝体联系的生后发育中可能发挥重要作用。