New mesomelic dysplasia with absent fibulae and triangular tibiae.

We report on two unrelated, sporadic cases of a mesomelic dysplasia characterized by absence of fibulae and severely hypoplastic, triangular-shaped tibiae. Moderate mesomelic shortness was present in the upper limbs with proximal widening of the ulnae. There was also axial skeletal involvement in both cases, characterized radiographically by an abnormal pelvis and marked bilateral glenoid hypoplasia. These cases appear to represent a new form of mesomelic dysplasia distinct from those previously delineated.

Fetal imaging in the skeletal dysplasias.

Second-trimester diagnosis of fetal skeletal dysplasia is becoming increasingly common. By careful examination of the fetus for skeletal mineralization, shape and size of long bones and cranium, and abnormalities of other organ systems, a definitive diagnosis can often be achieved by ultrasound. Fetal radiography is very helpful in giving more information about bone shape and mineralization as well as in confirming the diagnosis. Subsequent obstetric management should be dictated by the natural history of the disease, the parents' wishes, and the gestational age at diagnosis. Because many of these disorders have a high recurrence risk, genetic counseling and follow-up are an important part of the management of these patients.

Anti-vascular endothelial cell antibodies in severe preeclampsia.

There is mounting evidence to suggest that vascular endothelial cell injury plays an important role in the pathogenesis of preeclampsia. In this study an enzyme-linked immunoassay was used to demonstrate increased binding of immunoglobulins G and M to human umbilical vein endothelial cells by sera from women with severe preeclampsia as compared with normal pregnant control women. Fifty percent of women with preeclampsia versus 15.4% of control women had either immunoglobulin G or immunoglobulin M binding. In addition, immunofluorescent staining of normal renal cortical tissue with preeclamptic sera showed increased binding of immunoglobulin G to arterioles in patients with anti-vascular endothelial cell antibodies. These antibodies were not directed at HLA antigens and did not cross react with platelets. Interferon-gamma stimulation did not increase immunoglobulin binding. Antibodies to antigens expressed on vascular endothelial cells may be important in mediating the endothelial damage seen in preeclampsia.

Anti-vascular endothelial cell antibodies in patients with IgA nephropathy: frequency and clinical significance.

This study examined the frequency of anti-vascular endothelial cell (VEC) antibodies (Ab) in 72 patients with IgA nephropathy (IgAN), and their possible relationship to clinical and histological parameters of the disease. An enzyme immunoassay was developed to measure the binding of sera to endothelial cells grown to a confluent monolayer. Thirty-two percent of IgAN patients had serum anti-VEC activity as compared to 4% of controls (P = 0.004) and 9% of patients with other primary glomerulonephritis (P = 0.017). This was shown to be due to anti-HLA class I Abs in 6 of the 23 IgAN patients, and in the 1 control positive for anti-VEC activity. Hence 17 IgAN patients had anti-VEC Abs, predominantly of the IgA subclass. Stimulation of the endothelial cells with interferon-gamma and interleukin 1 did not increase the binding of these Abs. There was no correlation with circulating immune complex (IC) levels, and removal of ICs in positive sera by ultracentrifugation did not decrease anti-VEC binding. Significant correlations were found between anti-VEC Abs and proteinuria greater than 1 g/day (P = 0.044), as well as IgA anti-VEC Abs and C3 or IgA deposition in renal arterioles (P = 0.048). These IgA Abs may be an important marker of pathogenetic activity in IgAN.

Ovine fetal urine contribution to amniotic and allantoic compartments.

The ovine pregnancy has been extensively studied as a model for amniotic fluid metabolism potentially serving as a model for human oligohydramnios. However, it is recognized that the ovine pregnancy contains an allantoic fluid compartment not present in human pregnancies at term. Earlier studies in sheep suggested that the fetal urine contribution to allantoic fluid diminished at term, but without an explanation for maintenance of the significant volume of the allantoic cavity. In the present study we examined the relative fetal urine excretion of 3H-inulin into the allantoic and amniotic cavities in the near-term ovine pregnancy. Amniotic and allantoic volumes, as determined by technetium-labelled dextran and chromium-tagged erythrocyte dilution, were similar although there were significant differences in composition. The allantoic fluid compartment received an equal or greater proportion of fetal urine than did the amniotic fluid during the study period. These results indicate the importance of the allantoic fluid volume and composition in the study of ovine fluid dynamics.

Menopausal status associated with increased inhibition of blood coagulation.

Postmenopausal women receiving estrogen replacement therapy (ERT) are not as prone to inappropriate venous and arterial thrombosis as are younger women taking oral contraceptives. To establish whether menopausal status per se has any effect on the coagulation-fibrinolytic system normal premenopausal women (mean age 29 years) were compared with younger (mean age 23) and older (mean age 51) surgically menopausal women and a group of naturally postmenopausal women (mean age 53). The results show that in postmenopausal women, irrespective of age or type, the shift is away from clot formatiuon and toward clot inhibition and fibrinolysis as determined by static in vitro analysis. This was characterized by statistically significant increases in antithrombin III antigen, alpha 1-antitrypsin antigen, and plasminogen activity. These changes may help to explain in part why ERT does not appear to cause increased thrombosis in older women.