Critical timing of bladder embryogenesis in an adriamycin-exposed rat fetal model: a clue to the origin of the bladder

BACKGROUND/PURPOSE: Administration of Adriamycin (ADR) in utero to pregnant rats (vaginal plug, day 0) on gestational days (GD) 6 to 9 resulted in the offspring having a cluster of malformations, including absence of bladder in 100% of cases. This study aimed to determine the critical timing of the embryological window in bladder development in this animal model. METHODS: Timed-pregnant rats were divided randomly and injected intraperitoneally with ADR at 2 mg/kg on GD 6 to 9; GD 7 to 10; GD 8 to 11; GD 9 to 12; GD 6,8, and 9 (missing GD 7); and GD 6, 7, and 9 (missing GD 8). The control group received saline. Fetuses were harvested near term on GD 21 and dissected under a dissecting microscope and examined for gross anorectal and urogenital anomalies. RESULTS: Administration of ADR on GD 6 to 9 (n = 63); GD 7 to 10 (n = 42); and GD 6, 7, and 9 (n = 35) resulted in 100%, 83%, and 77% bladder agenesis respectively, in contrast with 53% and 26% on GD 8 to 11 (n = 36) and GD 6, 8, and 9 (n = 49), respectively. The control (n = 52) and the GD 9 to 12 (n = 27) groups all had normal bladder development. The proportion of other urogenital and anorectal anomalies mirror that of bladder agenesis. CONCLUSION: The results showed GD 7 to be the critical embryological timing in which bladder development can be affected by ADR, possibly by targeting the gene that is expressed in the embryonic bladder during this narrow time interval.     

Altered biochemical responses by rat Sertoli cells and peritubular cells cultured under simulated diabetic conditions

Summary The purpose of the present study was to determine whether the secretion of androgen-binding protein and lactate by 16-day-old rat Sertoli cells is altered when these cells are cultured in simulated diabetic conditions. Incorporation of ³H-uridine into RNA by peritubular cells cultured in simulated diabetic conditions was also studied. The cells were exposed to various concentrations of glucose, -hydroxybutyrate, sodium bicarbonate (to alter the pH of the medium), mannitol (to influence the osmolarity of the medium), or a combination of these compounds. All of the metabolic parameters when tested alone or in combination were capable of increasing lactate secretion by Sertoli cells above control values. Basal secretion of androgen-binding protein, however, was not influenced by any individual component or when all components were tested together. FSH-stimulated levels of androgen-binding protein secretion was depressed only when the Sertoli cells were exposed to all the components simultaneously. Incorporation of uridine by peritubular cells was decreased by exposing the cells to butyrate or mannitol, while no effect was observed with glucose treatment. These results indicate that Sertoli cell and peritubular cell function can be directly altered by several specific metabolic parameters associated with diabetes.     

Characteristics of mitochondria isolated by rate zonal centrifugation from normal liver and Novikoff hepatomas

Mitochondria were isolated from whole homogenates of normal liver and Novikoff hepatomas using reorienting rate zonal centrifugation on sucrose gradients. The activities of several mitochondrial-specific enzymes and ultrastructure were compared in the two tissues. Our results indicate that cytochrome oxidase, lipoamide dehydrogenase, malate dehydrogenase, and succinate dehydrogenase activities are all higher in liver homogenates than in Novikoff hepatoma homogenates. Mitochondrial hexokinase, however, is much greater in the hepatoma than in liver. The activity of these enzymes in isolated mitochondria displayed a much different pattern. Both cytochrome oxidase and succinate dehydrogenase activities were higher in hepatoma mitochondria than in liver mitochondria. Lipoamide dehydrogenase and malate dehydrogenase, conversely, were higher in liver mitochondria. Hexokinase was found to be virtually absent in liver mitochondria but plentiful in hepatoma mitochondria. Ultrastructural studies have shown that the hepatoma mitochondria are much smaller in size, which results in a decreased rate of migration into the gradient. These studies have also shown that normal liver consists of predominantly "condensed" forms of mitochondria, whereas hepatoma contained a majority of "twisted" species. Experiments using 1% bovine serum albumin in the homogenization procedures and in the gradient have confirmed earlier observations that bovine serum albumin is essential for optimal isolation of neoplastic mitochondria.     

Is the retractile testis a normal,physiological variant or an anomaly that requires active treatment?

Conventional teaching states that the retractile testis is a normal, physiological variant that descends spontaneously by puberty and requires no active treatment. Critical review of the literature, however, suggests that this complacent view may be inappropriate. Substantial overlap exists between the three seemingly separate entities of the late descending, the ascending and the retractile testes. This overlapping group probably accounts for the recently observed increased incidence of orchidopexies. Retractile testes that spend most of the time in an extrascrotal position are subject to the same adverse effects of higher temperatures as true undescended testes, regardless of whether they can be manipulated into the scrotum; what matters is where they actually reside most of the time. The evidence suggests that such retractile testes suffer similar pathological changes to true undescended testes if left to await spontaneous descent. Evidence is presented to support a radical, novel proposal that the retractile testis is a variant of the spectrum of pathological maldescended testes and requires active treatment. A new strategy is proposed for the management of this common pathology. Correspondence to: D. W. Goh     

Radical Resection of Periampullary Tumors in the Elderly: Evaluation of Long-term Results

Increasingly, patients of advanced age are coming for evaluation of periampullary tumors. Although several studies have demonstrated the safety of resecting periampullary tumors in older patients, few long-term survival data have been reported. Between 1983 and 1992 various periampullary masses were resected in 70 patients over age 65 (range 65–87 years). Total pancreatectomy was performed in 11 patients, and 59 patients underwent pancreaticoduodenectomy. The mean duration of hospitalization was 17 ± 15 days. Major complications occurred in 27 patients (39%), and operative mortality rate was 8.5%. Overall median survival was 24 months; and 5-year survival was 25%. Perioperative outcome was compared in patients aged 65 to 74 years and in patients ≥75 years old. The older age group required longer periods in the surgical intensive care unit postoperatively, but the long-term survival was similar in the two age groups. Radical resection with the intent to cure periampullary tumors is safe in selected patients of advanced age, and long-term survival is in the range of expected survival for younger patients with the same tumors.     

Fusion of childhood inguinal hernia induced by HGF and CGRP via an epithelial transition

BACKGROUND/PURPOSE: Recent evidence has suggested that calcitonin gene-related peptide (CGRP), which is released from the genitofemoral nerve, may trigger fusion of the patent processus vaginalis in children with inguinal hernia. The purpose of this study was to determine whether CGRP triggers the release of mesenchymal factors leading to subsequent fusion of the processus vaginalis. METHODS: The response of cultured epithelial cells derived from the patent processus vaginalis was analysed by a novel in vitro culture system. Epithelial cells lining fresh hernial sacs (removed at inguinal herniotomy) were detached enzymatically and cultured for 72 hours on Micropore filters, in the presence of either 100 ng/mL hepatocyte growth factor (HGF), 7.4 x 10(-6) mol/L CGRP (amino acids 1 to 37), 7.4 x 10(-6) mol/L CGRP (8 to 37) antagonist, 10% fetal calf serum (FCS), or serum-free medium (SFM) alone. Transformation from an epithelial cell morphology to motile mesenchymal fibroblast-like cells was assessed by an average migration score (AMS), ranging from 0 with no sign of migration, to 3 with greater than 75% of cells migrating. Confocal microscopy was used to record changes in expression of epithelial (cytokeratin) and mesenchymal (vimentin) markers, as well as actin. Beta-catenin also was examined because it is part of the molecular complex that links cadherins to actin resulting in cell-cell adhesion. RESULTS: Epithelial and mesenchymal markers underwent either down-regulation or up-regulation as epithelial cell sheets broke apart and individual cells commenced migration. The AMS after 72 hours of culture was 0.22 with SFM (control); with FCS the score was 1.4 (P < .01). The AMS score with CGRP (1 to 37) was 0.55 (P = .165) and with its analogue, CGRP (8 to 37), which is a competitive inhibitor, 0.67 (P = .309). Neither was significant. HGF caused a significant increase in the AMS to 1.56 (P = .01). CONCLUSION: Both HGF and FCS (which contains various undefined peptides and growth factors) produced transformation of hernial sac epithelial cells, whereas CGRP and its inactive analogue did not. CGRP receptors are localised to mesenchymal fibroblasts within the processus vaginalis connective tissue, suggesting that CGRP could act indirectly via HGF, which, in turn, promotes fusion of the processus vaginalis. In the future, a nonsurgical treatment of inguinal herniae in children might be possible by the local administration of agents which promote fusion.     

Rectal mucosal biopsy compared with laparoscopic seromuscular biopsy in the diagnosis of intestinal neuronal dysplasia in children with slow-transit constipation

BACKGROUND/PURPOSE: Intestinal neuronal dysplasia (IND) as a cause for severe chronic constipation remains controversial. The aim of this study is to examine the correlation between a deficiency of substance P (SP) immunoreactive nerve fibers in the colon and enzyme histochemistry of rectal biopsies in children with slow-transit constipation. METHODS: Fifty children with intractable constipation have been assessed by rectal biopsies examined with histochemical staining for lactate dehydrogenase, and 32 children among those 50 have been studied by laparoscopic seromuscular biopsy of the colon labelled with antibodies to SP using immunofluorescence methods. RESULTS: Four children have evidence of IND. Fifteen children, including all 4 IND cases, showed a deficiency of SP immunoreactivity. There is a significant correlation between giant ganglia and SP deficiency (P <.01). CONCLUSION: This study is attempting to propose that a deficiency of SP immunoreactivity in colonic circular muscle nerves may be used as a histologic marker for slow-transit constipation and that IND may be a small subset of patients with SP deficiency.