Biomedical subjects
Publications and source records attributed to A Krishna.
Acute Budd-Chiari syndrome caused by compression of the inferior vena cava by a space-occupying lesion in the liver is rare in children. We report a case where the compression was due to a large staphylococcal abscess in the right lobe of the liver. A high index of suspicion in such a case ensures early intervention and saves life.
Both hCG and PMSG treatments given either individually or sequentially between September and early February failed to induce ovulation in S. heathi, though they produced high degree of ovarian stimulation. The treatments induced ovarian enlargement, intense hyperaemia, marked changes in interstitial cells (ICs) and development of several antral follicles and varying degrees of abnormality in oocyte of most of the antral follicles. The percentage of abnormal oocytes in the ovary following hCG or PMSG treatment was dose-dependent.
The present investigation reports light and electron microscopical aspects of the main olfactory epithelium (MOE) of the insectivorous bat Scotophilus heathi. Serial frontal sections of the nose and associated structures reveal: 1) that the MOE is located on most of the ethmoturbinals and on the proximal upper portion of the nasal septum; and 2) that the vomeronasal organ is absent in this species. The ultrastructure of the MOE of Scotophilus heathi is similar to that observed in other vertebrates. Moreover, we did not observe significant morphological differences between the MOE of male and female animals. Nevertheless, the supra-nuclear region of the supporting cells of males and females shows a different amount and distribution of "lysosome-like" cell organelles at the two times of the year investigated.
Ovaries from hamsters on each day of the oestrous cycle at 09.00 h were observed for the number of mast cells, the pattern of mast cell degranulation, histamine concentration and blood flow. On day 4 (pro-oestrus), ovaries were also observed at 9.00, 15.00 and 21.00 h. Mast cell degranulation was evaluated by 3 criteria: (1) no degranulation = less than 5 granules dispersed from the cell; (2) moderate degranulation = 5 or more granules dispersed but less than 15, and (3) extensive degranulation = 15 or more granules released. Blood flow was determined using radio-active microspheres in anaesthetized animals. Mast cells were observed in fat pad (beyond 2 mm of the bursal mesothelium), bursa (within 2 mm of the bursal mesothelium), hilum and near ovarian blood vessels (these 4 regions are collectively called the ovarian complex). The distribution of ovarian mast cells was not uniform. Most mast cells were near ovarian blood vessels (42.2%) and in the fat pad (37.2%). A moderate number of cells were in the bursal wall (20%) and only a few cells were observed in the hilum (0.64%). Mast cell number remained unchanged on days 1-4 of the cycle in each ovarian compartment. However, summation of the number of mast cells in the entire ovarian complex revealed a significant decline in number at 15.00 h on pro-oestrus. Alterations in mast cell degranulation were primarily restricted to 2 periods of the cycle (pro-oestrus and di-oestrus). An increase in moderate but not extensive degranulation was observed in only the fat pad and bursa on day 2 when compared with day 1 values. In most ovarian compartments on pro-oestrus, degranulation was higher than on any other day of the cycle. At 15.00 h on pro-oestrus, extensive degranulation in bursa, fat pad and blood vessel regions (but not hilum) coincided with an increase in ovarian histamine and decline in number of mast cells; ovarian blood flow also increased at the time but remained unchanged the remainder of the cycle.(ABSTRACT TRUNCATED AT 250 WORDS)
In the absence of functional renal tissue on the right side, differentiating between a liver tumor and a renal tumor, both clinically and on routine imaging, is difficult. This clinical dilemma is highlighted here in a case report of a 2 year old girl with hepatoblastoma occurring in association with multicystic kidney. To our knowledge no other such case has been reported so far.
Mast cells, endothelial cells, basophils and platelets are potential sources of histamine in the ovary. Little is known about the role of the latter three cell types in ovarian function. Several studies have revealed changes in the number and degranulation (release of histamine) of mast cells in the ovary during the cycle. Mast cells degranulate on pro-oestrus in the rodent ovary, and mast cells numbers increase in the theca externa of the dominant follicle in the bovine ovary. In rodents, mast cells are limited to the ovarian hilum and are not observed in follicles, corpora lutea and interstitium; this contrasts with larger species such as man, cows and monkeys where mast cells are observed throughout the ovary. Evidence is accumulating that mast cell degranulation in the ovary may be regulated by neuronal input. Neurones have been shown to have close morphological relationships with mast cells in the ovary. Histamine participates in regulating capillary permeability and blood flow in the ovary. These actions are induced by injections of LH, yet the mechanism by which LH induces mast cell degranulation is unknown. Histamine stimulates ovarian contractility, ovulation and follicular progesterone secretion in vitro. Whether these actions of histamine occur in vivo are currently unknown. This review gives a chronological description of the discoveries of the effects of histamine on ovarian function and makes suggestions for future research in this area.
Ovaries were obtained from golden hamsters during proestrus and immersion-fixed for the immunocytochemical localization of albumin by the peroxidase-antiperoxidase method. Another group of ovaries were obtained from immature perfusion-fixed animals which had been stimulated for 48 or 96 h by gonadotrophins. Perfusion-fixed tissues were processed for the ultrastructural albumin localization using the protein A-gold technique. At the light microscopical level, albumin positive cells were seen more often in the corona radiata and the inner layer of the granulosa, but seldom in the outer layer. Thecal and interstitial gland cells revealed albumin reactivity as did the intra- and extravascular spaces. Using the electron microscope, enriched gold grains signalizing a positive albumin response were detected over lipid droplets of granulosal, thecal and luteal cells. Though labeled coated vesicles were absent, the following functional significance is proposed for this study: precursors of steroidogenesis or steroids may be transferred as ligands of albumin into or within the cell after a receptor-mediated uptake of the albumin ligand complex.
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A rare case of pulmonary blastoma in a neonate is reported. Only one other neonate has been documented in the available English literature. The treatment consisted of surgical excision only.
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The number of mast cells per microscopic field at 450X (0.123 mm2) was determined in the bovine ovary on Days 4, 10, and 19 of the cycle (Day 0 = estrus). Mast cells were observed in the theca externa of follicles, the external capsule of the corpus luteum, and in the stromal and hilar regions of the ovary. The stromal and hilar regions exhibited the highest number of mast cells (per field = 7.51-10.15) compared with the follicular and luteal compartments (2.65-3.70 mast cells/field). Most interestingly, on Day 19 a significant increase in the number of mast cells was observed in the theca externa of the dominant follicle (10.4 mast cells/field) compared with nondominant healthy follicles on Days 4 and 10 (2-3/field). After ovulation, the number of mast cells surrounding the corpus luteum on Day 4 was significantly lower than 19 values in the dominant follicle; this was further diminished on Day 10 of the cycle. These results indicate that the increase in mast cells associated with the dominant follicle on Day 19 may be related to its development and the decline in mast cells related to ovulation.
The present study describes the acute changes in steroids and human chorionic gonadotrophin (hCG) and FSH binding of preantral follicles induced by the gonadotrophin surges on the day of pro-oestrus. Preantral follicles were isolated by microdissection before (09.00-10.00 h), during (15.00-16.00 h) and after (21.00-22.00 h) the LH surge on pro-oestrus. Follicles at each time-period were pooled and steroid concentrations and gonadotrophin receptors determined. Before the LH surge, concentrations of progesterone and androstenedione were 40.8 +/- 6.1 (S.E.M.) and 10.7 +/- 3.9 fmol/follicle respectively. At the peak of the LH surge, progesterone and androstenedione concentrations in preantral follicles increased to 848 +/- 186 and 129 +/- 33 fmol/follicle respectively. Immediately after the LH surge, progesterone increased to 1238 +/- 97 fmol/follicle whereas androstenedione declined to 13.3 +/- 2.1 fmol/follicle. Oestradiol was less than 6 fmol/follicle throughout these periods. Binding of hCG and FSH to preantral follicles increased after the surge (hCG, 56 +/- 2.6 c.p.m./follicle; FSH, 29.8 +/- 4.0 c.p.m./follicle) when compared with values obtained before the surge (hCG, 15.8 +/- 4.0 c.p.m./follicle; FSH, 14.1 +/- 1.9 c.p.m./follicle). Also, hCG binding increased significantly (P less than 0.05) from 09.00 to 21.00 h (56 +/- 2.6 c.p.m./follicle). In order to ascertain which follicular compartments were affected by the LH and FSH surges on pro-oestrus, granulosa cells and thecae from preantral follicles were isolated and steroid concentrations and LH and FSH binding measured.(ABSTRACT TRUNCATED AT 250 WORDS)
In-vivo changes in steroidogenesis in preantral hamster follicles following exposure to the LH surge could be mimicked by stimulation with exogenous LH in vitro. Luteinizing hormone given only during the first hour (media were changed every hour) of a 6-h incubation promptly increased the concentration of androstenedione and adenosine 3':5'-monophosphate (cAMP) in the media and this was followed by a gradual decline to less than 20% of the peak value; progesterone in media was not detectable with a single LH stimulation. However, LH given every hour increased progesterone and cAMP concentrations in the media throughout the period of incubation, but the transient increase and subsequent decline in androstenedione was still observed. The decline in androstenedione release by preantral follicles was apparently due to a lack of steroid precursor and not to either inhibition of hydroxyl-lyase or lack of LH or cAMP stimulation. Exogenous dibutyryl cAMP (dbcAMP) and 8-Br-cAMP mimicked the effects of LH on the pattern of follicular androstenedione release into the media; however, dbcAMP and 8-Br-cAMP did not increase concentrations of progesterone in vitro. In preantral follicles, LH stimulated cAMP release into the media and apparently inhibited phosphodiesterase activity, since methyl isobutylxanthine (MIX) did not potentiate the effect of LH on cAMP. Follicle-stimulating hormone also increased androstenedione and cAMP in the media of the preantral follicles in a manner similar to that of LH, except that between 4 and 6 h of incubation the release of androstenedione and cAMP was less than that produced by stimulation with LH.(ABSTRACT TRUNCATED AT 250 WORDS)
On each day of the estrous cycle hCG binding to follicle increased from 09.00 to 21.00 h; then hCG binding was static until 09.00 h of the next day. FSH binding did not exhibit rhythmicity. This pattern of hCG binding may be related to the pulsing of LH on each cycle day.