PubMed Health⌕ Search

Biomedical subjects

B L Sheppard

Publications and source records attributed to B L Sheppard.

At least 37 records · Page 2Linked to original sources
PubMed1987

Endometrial morphological changes in IUD users: a review.

The introduction of an intrauterine device into the uterine cavity induces a foreign body reaction in the surrounding endometrium which is characterized by the infiltration of polymorphonuclear leucocytes and macrophages into the endometrial stroma and subsequently through the surface epithelium. Leucocyte migration is greater with copper IUDs than with inert IUDs. Ulceration of the surface epithelium, haemorrhage of erythrocytes and microthrombosis of stomach capillaries occur in the functional endometrium in contact with inert and copper IUDs. In endometrium adjacent to, but not in contact with, the IUD gaps appear in the endothelial lining of small blood vessels without a haemostatic response. The most striking response in endometrium exposed to progesterone-releasing IUDs is the occurrence of dilated, thin-walled vesicles, associated with a thinning of the surface epithelium and a decidual reaction in the stroma. A uniform suppression of the endometrium in progesterone IUD users is always found after six months of treatment, whereas the insertion of IUDs releasing 20-30 micrograms levonorgestrel induce a profound uniform suppression of the functional endometrium throughout the uterus after only four weeks.

Endometrium↗
PubMed1987

The fibrinolytic enzyme system in normal menstruation and excessive uterine bleeding and the effect of tranexamic acid.

The fibrinolytic enzyme system of menstrual and peripheral blood was studied in three groups of women: Group 1, 20 subjects (mean age 37.2 years) with normal menstrual loss; Group 2, 20 patients (mean age 39 years) with dysfunctional uterine bleeding studied before treatment, and Group 3, during treatment with a fibrinolytic inhibitor, tranexamic acid (AMCA) (1 g 8-hourly). The fibrinolytic activity (plasminogen activator and plasmin) of menstrual blood was significantly higher than that of peripheral blood in the three groups (p less than 0.001). Both plasminogen activator and plasmin were higher in the menstrual blood of patients with menorrhagia (Group 2) compared with the control subjects (Group 1) (p less than 0.001 and p less than 0.1 respectively). Treatment with AMCA significantly reduced both plasminogen activator (p less than 0.01) and plasmin (p less than 0.05) in the menstrual blood of patients with menorrhagia (Group 3). No significant differences in fibrinolytic activity were found in peripheral blood between Groups 1 and 2; however, both plasminogen activator and plasmin were significantly lower (p less than 0.01) in Group 3 than in Group 2. Plasmin activity was also significantly lower (p less than 0.05) in Group 3 compared to Group 1. These findings confirm the presence of increased fibrinolytic activity in the uterus in excessive (dysfunctional) bleeding.

Administration, Oral↗
PubMed1986

The placental bed biopsy: review from three European centers.

This review derives from extensive experience with the placental bed biopsy technique in three centers over the last 30 years. A placental bed biopsy, usually taken at cesarean section, must include basal decidua and subjacent myometrium from the central zone of the placental site. Attention is drawn specifically to the sampling errors and to the pitfalls in morphologic interpretation of tissues, both maternal and fetal, that are continuously changing throughout the course of pregnancy. The features of the normal placental bed and of vascular lesions in pathologic pregnancies are briefly reviewed. Extension and elaboration of the technique and its more widespread use could contribute to the elucidation of many of the unresolved problems in human pregnancy.

Abortion, Spontaneous↗
PubMed1986

A morphometric study of the effect of oral norethisterone or levonorgestrel on endometrial blood vessels.

A morphometric study was undertaken to quantitate vessel numbers in uterine biopsies from a control group of patients, patients with dysfunctional uterine bleeding and patients taking low dose norethisterone or levonorgestrel. Vessels were counted at the endometrial/myometrial junction and in the functional endometrium just below the surface epithelium. The number of arteries at the endometrial/myometrial junction was found to be decreased in patients taking norethisterone and levonorgestrel. An increase was found in the total number of veins and in the number of dilated veins in the functional endometrium of the progestogen-treated specimens. Dilated veins were frequently found close to the endometrial surface and it is possible that they may be the major cause of the irregular bleeding associated with low dose oral progestogens.

Administration, Oral↗
PubMed1984

The pathology of dysfunctional uterine bleeding.

The mechanism of dysfunctional uterine bleeding remains unknown. Recent studies suggest that the majority of cases of dysfunctional uterine bleeding are due to local endometrial, or myometrial, dysfunction. Changes in the pattern of production of prostaglandins PGE2, PGF2 alpha, prostacyclin and thromboxane and increased fibrinolytic activity in the endometrium have been implicated in this disorder. Successful treatment of excessive menstrual bleeding with the prostaglandin synthetase inhibitor mefenamic acid and the fibrinolytic inhibitors epsilon amino caproic acid and tranexamic acid further substantiates the role of prostaglandins and fibrinolysis in pathological menstruation. The relationship between uterine mast cells, heparin-like activity and menstrual bleeding still needs to be elucidated. Further studies are required to improve our understanding of the pathogenesis of dysfunctional uterine bleeding, so that advances can be made in a specific treatment to restore normal menstrual function.

Blood Platelets↗
PubMed1983

The effects of intrauterine contraceptive devices on the ultrastructure of the endometrium in relation to bleeding complications.

The effects of inert (Lippes Loop D and Dalkon Shields) and medicated (copper 7, copper T, and Progestasert) intrauterine contraceptive devices (IUDs) on the ultrastructure of the endometrium were studied in intact human uteri. The most striking morphologic changes induced by the inert and copper-bearing devices were erosion of the surface epithelium and extensive microthrombosis in stromal capillaries of the endometrium in contact with the device. These abnormalities were associated with extravascular thrombi, erythrocytes, and fibrin deposition in the adjacent stroma. Capillary microthrombosis and leukocyte infiltration into the uterine cavity were most extensive around the active part of the copper-bearing devices. With the Progestasert erosion of surface epithelium was rarely seen, but the intact epithelial lining had fewer ciliated cells with flattened and shortened cilia. Large dilated venules were a common finding below the surface epithelium adjacent to the active part of the Progestasert; capillary microthrombosis was found only below the inert arms of the Progestasert. The vascular response of the endometrium to IUDs appears, therefore, to be directly related to the type and proximity of the device. The morphologic changes induced in both surface epithelium and the microvasculature of the endometrium are the likely explanation of the uterine bleeding problems associated with IUDs but are probably intrinsic to the mode of action of the IUD in interfering with implantation.

Adult↗
PubMed1983

An ultrastructural study of menstrual blood in normal menstruation and dysfunctional uterine bleeding.

Menstrual fluid was obtained from the uterine cavity and vagina in 20 women within the first 48 h of menstruation. Ten of the women had normal menstrual cycles and blood loss and ten were patients with dysfunctional uterine bleeding. The menstrual samples were examined by electron microscopy for the presence of fibrin and platelets and nearly all were found to contain both fibrin and aggregating platelets. By a simple quantitative system no differences in fibrin and platelet content were found between samples collected from the uterine cavity or the vagina. Likewise no difference was found in the morphology of fibrin and platelets between women with normal menstrual loss and patients with dysfunctional uterine bleeding.

Blood Platelets↗
PubMed1982

The effect of the progesterone-releasing intrauterine device on uterine endometrium and fallopian tube epithelium.

A scanning and transmission electron microscopy study was undertaken of the effect of the progesterone releasing intrauterine device (Progestasert, Alza Corporation, USA) on the uterine endometrium and fallopian tube epithelium. Small erosions of surface epithelium and microthrombosis of stromal capillaries were found in the endometrium below the inert part of the device. A reduction of ciliated cells and shortened cilia were seen in the endometrium below the active part of the device and large dilated venules were present in the underlying stroma. Fallopian tubes from IUD patients contained fewer ciliated cells than those of the controls. The morphological changes described are likely to be major factors responsible for the irregular bleeding which occurs with Progestasert IUDs and the possible increase in tubal pregnancy.

Endometrium↗
PubMed1981

An ultrastructural study of utero-placental spiral arteries in hypertensive and normotensive pregnancy and fetal growth retardation.

Uteroplacental spiral arteries in placental bed biopsies and placentas form 80 pregnancies were studied by light and electron microscopy; of these 30 were complicated by fatal growth retardation(less than 10th centile) and 45 by hypertension during pregnancy. The physiological changes of the spiral arteries and the vascular pathology present in hypertensive pregnancy and fetal growth retardation were investigated. In normotensive pregnancies complicated by fetal growth retardation, the physiological changes of pregnancy frequently did not extend beyond the decidual segments of the utero-placental arteries. In pregnancies complicated by pre-eclampsia, the physiological changes of pregnancy were not always restricted to the decidual segments of the utero-placental arteries. Atheromatous-like lesions of similar morphology were found in spiral arteries from both normotensive and hypertensive pregnancies complicated by fetal growth retardation. No arteriopathy was found which was specific for pre-eclampsia.

Arteries↗
PubMed1980

The response of endometrial blood vessels to intrauterine contraceptive devices: an electron microscopic study.

The ultrastructure of the vascular supply of the endometrium in uteri containing inert and copper bearing intrauterine contraceptive devices (IUCDs) has been compared with that in uteri removed at comparable stages of the menstrual cycle for dysfunctional uterine bleeding. In the endometrium from all uteri containing inert and copper IUCDs, stromal capillaries below the devices showed extensive microthrombosis with platelet and fibrin aggregations filling gaps in the endothelial linings of the vessels. Considerable stromal haemorrhage and erosion of surface epithelium was associated with this vascular pathology. In the uteri removed for dysfunctional bleeding, microthrombosis was a rare occurrence. In the stromal vessels of the endometrium not in contact with the devices, the surface epithelium was usually intact and the underlying stromal capillaries often showed breaks in the endothelial lining but without a haemostatic plug. Leucocyte migration into the stroma was more evident in association with the copper IUCDs than the other devices. The ultrastructural changes in the microvasculature of the endometrium associated with IUCDs did not appear to be related to a stage of the menstrual cycle. The extent and type of microvascular changes appeared to be related to the proximity and surface area of the IUCD and to the presence or absence of copper in the device.

Adult↗
PubMed1980

Scanning and transmission electron microscopy of material adherent to intrauterine contraceptive devices.

The material adherent to intrauterine contraceptive devices (IUCDs) has been studied by transmission and by scanning microscopy coupled with X-ray microprobe analysis. Inert (Lippes Loop D, Saf-T-Coil and Dalkon shield) and medicated (Copper 7 and Progestasert) IUCDs were removed for examination from uteri immediately after hysterectomy. The cellular material identified on the surface of all inert IUCDs consisted mainly of macrophages with some polymorphonuclear leucocytes, erythrocytes, a few platelets and fibrin fibres. Polymorphonuclear leucocytes were the principle cells on the copper devices. Larger numbers of cells were evident on the inert arms than on the active part of the Progestasert device. All the devices examined exhibited varying amounts of surface calcium deposition. The IUCDs which had been in utero for longer periods showed the greatest amount of calcium deposition. Although a less rapid calcium deposition appeared to occur on the Progestasert device, this deposition may influence the release of medications from IUCDs which are retained in utero for longer periods than one year.

Calcium↗