Structure of the corpus luteum in the ovulatory polycystic ovary.

BACKGROUND: Women with polycystic ovaries (PCO) have a wide spectrum of presentation from anovulation and amenorrhoea to apparently regular, ovulatory menstrual cycles. We have recently reported a subtle defect in steroidogenic function in the luteal phase in the latter and an increase in the number of degenerating corpora lutea (CL) were observed in ovulatory PCO (ovPCO) during dissection. The possibility was therefore investigated of differences in structure or degeneration in CL formed during ovulatory cycles in women with PCO. METHODS: This study compared the histology of the CL in ovPCO with that in the normal ovary. Corpora lutea were collected from nine normal ovaries (days 1-27 of the cycle) and from 13 women with ovPCO (days 5-38). RESULTS: Variations in the degree of regression, both in relation to onset of menses and between different areas within individual CL, were recorded in both groups. During development and regression no obvious differences were observed between either group apart from an apparent increase in luteal haemorrhage, which was more common and more extensive in CL from PCO. CONCLUSIONS: The findings suggest that possible luteal phase abnormalities of steroid secretion in women with ovulatory PCO are not associated with obvious morphological defects in the CL, however it is possible that the persistence of luteal structures seen in PCO was a consequence of increased luteal haemorrhage.     

Phenotypic characterization of regulatory CD4+CD25+ T cells in rats

CD25 has become widely used as a marker for a subset of regulatory CD4(+) T cells present in the thymus and periphery of mice, rats and humans. However, CD25 is also expressed on conventionally activated T cells that are not regulatory and not all peripheral regulatory T cells express CD25. The identification of a stable and unique marker for regulatory T cells would therefore be valuable. This study provides a detailed account of the phenotype of CD4(+)CD25(+) regulatory T cells in rats. In the thymus, CD4(+)CD8(-)CD25(+) cells were found to have a more mature phenotype than the corresponding CD4(+)CD8(-)CD25(-) cells with respect to expression of Thy1 (CD90), CD53 and CD44, suggesting that CD25 expression, and perhaps commitment to regulatory function, might be a late event in thymocyte development. CD4(+)CD25(+) cells in both the thymus and periphery were found to have enriched and heterogeneous expression of activation markers such as OX40 (CD134) and OX48 (an antibody determined in this study to be specific for CD86). CD4(+)CD25(+) T cells were also found to have enriched expression of CD80, at both the mRNA and protein level. However, functional studies in vitro and in vivo showed that neither OX40 or CD86 were useful markers for the further subdivision of regulatory T cells. Our studies indicate that, at present, CD25 remains the most useful marker to enrich for regulatory CD4(+) T cells in rats and no further subdivision of the regulatory component of CD4(+)CD25(-)CD45RC(low) T cells has yet been achieved.     

Red degeneration of a leiomyoma masquerading as retained products of conception

BACKGROUND: The incidence of leiomyomas in pregnancy is approximately 1%. Their presence has been linked to spontaneous abortion, premature labor, soft tissue dystocia, uterine inertia, fetopelvic disproportion, malposition of the fetus, retention of the placenta, and postpartum hemorrhage. CASE: This case report documents a seldom-described event of a submucous leiomyoma masquerading as retained products of conception. The patient presented 4 weeks postpartum with complaints of urinary retention and heavy bleeding with cramping. Examination revealed a large mass resembling placental tissue filling the vaginal vault. The necrotic mass was removed with blunt and sharp dissection. The final pathology report revealed a degenerating leiomyoma. CONCLUSION: Complicating factors associated with this fibroid included a history of spontaneous abortion and preterm labor, as well as fetal malpresentation and carneous degeneration of the leiomyoma. Gestational myomas, although rare, can have an unusual appearance that may be misinterpreted.     

Immunolocalization of 3β-hydroxysteroid dehydrogenase in human adrenal cortex and in its disorders

Immunohistochemical localization of 3β-hydroxysteroid dehydrogenase/Δ^5→4-isomerase (3β-HSD), which converts Δ⁵-3β-hydroxysteroids to Δ⁴-3-ketosteroids, was performed in the human adrenal gland and in its disorders by employing a specific antibody raised against the enzyme purified from human placenta. Immunoreactivity of 3β-HSD was present in all three cortical zones of the adrenal glands obtained at autopsy, while in surgically removed adrenal glands, immunoreactivity was dominant in the zona fasciculata (ZF), with faint immunoreactivity in the zona glomerulosa (ZG) and the zona reticularis (ZR). Intracortical localization of 3β-HSD in the adrenal glands obtained at autopsy may represent an adrenal adaptation to antemortem stress, with shifting of adrenal pregnenolone- a substrate of 3β-HSD - as well as steroid 17α-hydroxylase from adrenal androgen synthesis to glucocorticoid synthesis. In adrenocortical hyperplasia, marked immunoreactivity was observed in the ZG and outer ZF in adrenal glands with idiopathic hyperaldosteronism and in the ZF and ZR, especially in cortical micronodules, in the adrenal glands associated with Cushing’s disease. In aldosteronoma and Cushing’s adenoma, immunoreactivity of the enzyme was much more intense in large clear tumor cells than in small compact tumor cells. Immunolocalization of 3β-HSD can yield important information toward an understanding of adrenal steroid metabolism in both physiological and pathological processes.     

The early phase of experimental acute renal failure

Experiments were conducted to establish whether diminished solute reabsorption in the loop of Henle during acute renal failure could explain the loss of urinary concentration and participate in generating a tubuloglomerular feedback-mediated reduction in filtration rate. The electrolyte content of the fluid in the ascending limb of the loop of Henle was determined in situ by monitoring its electrical conductivity after propulsion into the distal tubule with a sudden burst perfusion. The value of the minimum electrolyte concentration decreased exponentially with increasing equilibration time, reaching a steady-state value equivalent to 27±9 mM NaCl in normal kidneys, 34±15 mM in mercuric chloride kidneys and 53±22 mM following ischaemia. A mathematical model was derived to describe the process of sodium chloride dilution from which it was possible to calculate both the permeability and transport velocity of the cortical thick ascending limb. In the normal kidney, the transport velocity was calculated to be 4.65±0.92 ·10^–5 cm/s, a value not significantly different from that of the mercuric chloride or ischaemic kidneys, and the estimated permeability was 1.13±0.52·10^–5 cm/s, not different from that of the mercuric chloride kidneys but significantly lower than that calculated for the ischaemic kidneys. It is concluded that for the more severely damaged ischaemic model, the loss of urinary concentrating ability was accompanied by a reduction in diluting ability of the ascending limb of the short loop of Henle, which appears to be due, at least in part, to an elevation of the passive permeability to sodium chloride in this segment.     

Noradrenaline and neophobia

Lesions of the ascending noradrenergic bundles using the selective neurotoxin 6-hydroxydopamine increased neophobia to a number of novel tastes in rats. These lesions also increased some, but not all, measures of neophobia in novel environments. The results are discussed with reference to a recent hypothesis which suggests that the noradrenergic projections of the locus coeruleus mediate some aspects of fear and anxiety. Contrary to the prediction of this hypothesis, the noradrenergic lesions significantly increased rather than decreased neophobia. While these results point to an involvement of ascending noradrenergic systems in fear, at present the nature of this involvement cannot be specified in detail.     

The bone marrow in disseminated Mycobacterium avium-intracellulare infection

Thirteen cases of disseminated Mycobacterium avium-intracellulare (MAI), representing a total of 27 bone marrow specimens, were studied. The patients ranged from 25 to 46 years of age and included ten immunocompromised and three immunocompetent hosts. Peripheral blood findings included anemia in all patients, leukopenia in 73%, thrombocytopenia in 45%, and pancytopenia in 45%. Fourteen of the specimens (52%) showed granulomas ranging from small, subtle lymphohistiocytic aggregates to larger lymphohistiocytic lesions and clusters of epithelioid histiocytes; almost half of these lesions were missed initially. Rare acid-fast bacilli were seen in only one case, but 53% grew MAI on culture. In one case of the acquired immunodeficiency syndrome, culture was positive in the absence of inflammation or AFB on staining. These findings are not significantly different from those reported in disseminated Mycobacterium tuberculosis infection.