Chronic fetal hypoxia increases activin A concentrations in the late-pregnant sheep.

OBJECTIVE: To determine whether activin A concentrations are altered in chronic fetal hypoxemia and intrauterine fetal growth restriction (IUGR). DESIGN: In vivo animal experimental model. SETTING: Department of Physiology, Monash University. POPULATION: Chronically catherised fetal sheep in late pregnancy. METHODS: Chronic fetal hypoxia and IUGR were experimentally induced by single umbilical artery ligation (SUAL) in catheterised fetal sheep. Maternal and fetal blood samples and amniotic fluid (AF) samples were collected during surgery and thereafter on alternate days, until the time of delivery for analyte measurement. Fetal blood gas parameters were measured daily. MAIN OUTCOME MEASURES: Plasma and AF was used to analyse activin A, prostaglandin E2 (PGE2) and cortisol and fetal blood gas analysis was undertaken in whole blood. RESULTS: SUAL produced asymmetric IUGR and non-acidaemic chronic fetal hypoxia and resulted in preterm labour (129 [3] days). AF activin A concentrations were 10-fold higher in the SUAL group than in controls whereas levels in the fetal and maternal circulations were similar between groups. CONCLUSIONS: SUAL-induced IUGR and fetal hypoxaemia increases AF activin A. This may be an important adaptive or protective response to IUGR.

Pseudosaccharin amine derivatives: synthesis and elastase inhibitory activity.

Pseudosaccharin amines were synthesized from saccharin either by the reaction of pseudosaccharin chloride with amines, or via thiosaccharin which was treated with amines yielding thiosaccharinates, and their reaction with glacial acetic acid. This route gave lower yields than the first way. The synthesis of alkyl [(1,1-dioxo-benzo[d]isothiazol-3-yl)amino]alkanoates as possible Human Leukocyte Elastase (HLE) inhibitors was realized by the reaction between amino acid esters and pseudosaccharin chloride. Hydrolysis of the esters was possible under aqueous basic conditions. Selected compounds were screened for elastase inhibitory activity. Compounds 4k and 4m were found to be reversible inhibitors of HLE with Ki values of 45 microM and 60 microM.

Physiological and regulatory roles of activin A in late pregnancy.

Unexplained fetal death in utero in late pregnancy represents an increasing proportion of perinatal deaths. It has been assumed that critical hypoxia is the likely mechanism underlying these losses, but the lack of a physiological marker has hampered both confirmation and prediction which could lead to timely intervention. In this paper, we report studies on hypoxia that we have performed in chronically cannulated late pregnant sheep, complemented by parallel investigations undertaken in human pregnancies. Our initial studies were directed towards determining activin secretion in the fetus and mother during late gestation, and immediately after fetal surgery using a sheep model. This led us to propose that there may be a relationship between hypoxia and activin A, follistatin and prostaglandin (PG) release from the feto-placental unit. Subsequent studies have been directed towards examining this potential relationship in sheep and in humans with compromised pregnancies. As a result of these studies, we have identified a potential mechanism by which activin A may be involved in regulating the response of the fetus to hypoxic insult. Activin A and follistatin concentrations increased in late gestation in ovine maternal plasma and in fetal fluids. Feto-placental hypoxemia or maternal isocapnic hypoxemia, leading to fetal hypoxia, were specific triggers for an acute increase in fetal activin A and follistatin concentrations during late gestation. The source and secretion of activin A, follistatin, and the associated release of PGE(2,) from within the feto-placental unit varied according to the site of the insult. The concomitant secretion of activin A and PGE(2) into the fetal circulation and amniotic fluid during reduced uterine blood flow provides an insight into the physiological regulatory mechanisms that might be involved. Changes observed in maternal activin A concentrations in mid and late gestation in the human may also be associated with fetal compromise. In human pregnancies, elevated activin A concentrations were observed in maternal plasma in mid and late gestation, in association with severe pre-eclampsia and with severe fetal growth restriction, compared to those observed in pregnancies with constitutionally small, healthy fetuses. Activin A was also elevated in maternal and arterial cord plasma in women at term during labour and immediately prior to undergoing emergency Caesarean section for failure to progress. These findings offer exciting new possibilities to gain insights into the mechanisms that underlie the maintenance of fetal wellbeing and provide a rationale for the potential that activin A may prove to be a useful clinical marker of fetal distress.

Combined xylazine and ketamine as an analgesic regimen in sheep.

OBJECTIVE: To determine whether low dose xylazine with ketamine reduces the concentrations of cortisol and prolactin in sheep postoperatively and to characterise the effects of the drugs on behaviour during recovery. DESIGN: Analysis of variance was used to compare the effects of anaesthesia, surgery and combined ketamine/xylazine treatment on the plasma cortisol and prolactin concentrations and on behavioural variables in pregnant ewes subjected to abdominal surgery. PROCEDURE: Twelve ewes were randomly assigned to receive either ketamine/xylazine or placebo in association with anaesthesia and surgery. Both groups of ewes underwent anaesthesia alone followed a week later by anaesthesia with laparotomy and hysterotomy. Plasma cortisol and prolactin concentrations were assayed during these procedures and for 5 days afterwards. Behavioural observations were made remotely during recovery from anaesthesia and anaesthesia plus surgery. RESULTS: The concentrations of cortisol in the plasma of pregnant ewes undergoing surgery were increased by preoperative handling and the onset of thiopentone/halothane anaesthesia, with a further increase during surgery (P = 0.033). Cortisol concentrations decreased over the first four postoperative hours (P = 0.029) and were normal by 24 h. The drug treatment did not affect the immediate responses of ewes to anaesthesia or surgery, although treated ewes had lower cortisol concentrations than saline-treated controls over the first five postoperative days (P = 0.018). Prolactin concentrations increased in response to anaesthesia (P = 0.047), but were not affected by surgery or the drug treatment. Drug-treated ewes had prolonged sleeping time after surgery (P = 0.002), but they took no longer to stand than saline-treated controls and required fewer attempts to stand successfully (P = 0.025). CONCLUSION: At the doses used, ketamine and xylazine did not mitigate the immediate endocrine consequences of surgery but the behavioural data provide a basis for further investigations that may lead to improvements in analgesic treatments.

Late aneurysm formation in a femoro-popliteal polytetrafluoroethylene graft.

Since improvement in the material, true aneurysms and pseudoaneurysm formations have become relatively rare complications after femoro-popliteal reconstruction with polytetrafluoroethylene (PTFE) grafts. We report a case of late graft rupture and pseudoaneurysm formation within the straight femoral part of a femoro-popliteal bypass with reinforced (PTFE-wrapped) Gore-Tex graft. The rupture occurred 7 years after implantation without history of direct traumatization. Intraoperatively the whole bypass showed macro- and microscopically visible deterioration of the wall with almost complete disruption at the site of the aneurysm. The graft had to be replaced completely. In conclusion, we recommend continuous long-term follow-up of these patients preferably with duplex ultrasonography.

Prostaglandin E2 acts via the hypothalamus to stimulate ACTH secretion in the fetal sheep.

Prostaglandin (PG) E2 is secreted into the fetal circulation during late gestation in the sheep. Exogenous infusion of PGE2 is associated with robust increases in the circulating concentrations of ACTH and cortisol and it has therefore been proposed that endogenous PGE2 modulates the activity of the fetal HPA axis, which is the primary determinant of parturition and essential for the maturation of vital organ systems. The sites of action of PGE2 within the HPA axis have not been clearly established. We have compared the effects of PGE2 infusion on ACTH and cortisol concentrations in intact fetuses and in those whose pituitaries were surgically disconnected from hypothalamic control (hypothalamo-pituitary disconnected; HPD fetuses operated at 111-113 days gestational age). The effect of advancing gestational age on these responses was investigated by infusing PGE2 at 121, 131, 141 and 148 days of gestation. The functional integrity of the pituitary corticotrophs was tested by injecting CRH (1 microgram) into intact and HPD fetuses at day 125. This test was repeated for the HPD fetuses at 160 days. The responsiveness of the adrenal glands was also tested by injecting 2.5 micrograms/kg synthetic ACTH1-24 (Synacthen) into both groups of fetuses at day 135, with the HPD group retested at day 155. PGE2 infusion was associated with a robust increase (P < 0.001) in plasma immunoreactive (ir) ACTH in intact fetuses at all gestational ages while HPD fetuses did not respond, except at day 148 when the response was small. Similarly, cortisol concentrations were increased (P < 0.001) during PGE2 infusion in intact fetuses but not in HPD fetuses, except for a minor increase at 148 days. The response of irACTH to exogenous CRH was similar in intact and HPD fetuses at 125 days and this response was maintained in HPD fetuses at day 160. The cortisol response of intact fetuses to ACTH1-24 exceeded that of HPD fetuses at day 135 and, in HPD fetuses, this response was unchanged when they were retested at 155 days, indicating that their adrenal responsiveness did not wane with time. We conclude that the effects of PGE2 on the fetal HPA axis are exerted predominantly or exclusively at a level above the pituitary gland.

Randomized clinical trial of antithymocyte globulin induction in renal transplantation comparing a fixed daily dose with dose adjustment according to T cell monitoring.

Antithymocyte globulin (ATG) has been used successfully for induction therapy as well as for treatment of established allograft rejection. However, this therapy has often been associated with problems of overimmunosuppression and increased costs. In a randomized clinical trial, we compared the immunosuppressive benefits, complication rates, and treatment costs when ATG is given as a fixed daily dose or when the dose is adjusted daily according to its biologic effects on T cells. Forty-five recipients of cadaver renal allografts were randomized into two groups. In group 1 (n = 23), ATG (ATGAM) was administered in variable doses to maintain the absolute number of peripheral CD3 T cells at 50-100/microliters. In group 2 (n = 22), ATG was given at a fixed dose of 15 mg/kg/day. All patients received azathioprine and prednisone. ATG was discontinued at 7-14 days when cyclosporine was introduced. In both groups, CD2, CD3, CD4, CD8, and CD19 cells were measured by flow cytometry and the levels of cytokines IL-1 beta, IL-2R, ICAM-1, IL-6, IL-7, and levels of cytokines IL-1 beta, IL-2R, ICAM-1, IL-6, IL-7, and levels of cytokines IL-1 beta, IL-2R, ICAM-1, IL-6, Il-7, and IL-10 were measured by ELISA. In group 2, the levels of all T cell subsets were profoundly suppressed. In group 1, the number of CD3 and other T cells was maintained at about 100 cells/microliters, while the CD19 T cells remained unsuppressed. Cytokine levels were greatly suppressed in group 2 compared with group 1, except for IL-10 levels, which remained elevated in the latter group. Patient survival, graft function, and the incidence of acute and recurrent rejections were similar in the two groups. Bone marrow suppression and infective complications were greater in group 2 than in group 1. The mean daily dose and the total quantity of ATG used in group 1 were significantly smaller than in group 2, resulting in a savings of $2,398.00 per patient per treatment. It is concluded that monitoring of ATG by its biologic effects on T cells is a rational and safe method of regulating the dose of this important agent; in this way, it is possible to reduce the total amount of the drug given to patients with consequent reduction in undesirable complications as well as in the cost of treatment without loss of immunosuppressive benefits.

Hot-knife conization of the cervix: clinical and pathologic findings from a study introducing a new technique.

OBJECTIVE: To introduce an alternative method for conization of the cervix using a Teflon-coated hot knife and to evaluate thermal distortion, adequacy of excision, operating time, blood loss, and short- and long-term effects of this method. METHODS: Between 1987-1993, 88 patients underwent cervical conization using a Teflon-coated hot knife at temperatures ranging from 110-130C. Histopathologic slides were reviewed simultaneously by two pathologists, who assessed thermal distortion, adequacy of excision, and interpretability of the surgical margins. Clinical information was obtained prospectively, including operating time, blood loss, and depth and volume of the excised cone. In addition, data were accumulated retrospectively from 40 randomly selected patients who underwent cold-knife conization between 1985-1990. Short- and long-term data were assessed for healing and scarring and the adequacy of postoperative Papanicolaou smears in the hot-knife patients. RESULTS: Thermal injury was minimal, with 300 mu or less in 83 patients (92%) and 350-600 mu in four patients. One patient had thermal distortion of 1500 mu. All slides were interpreted adequately. Blood loss was mild to moderate in 84 of 88 patients (95%) in the hot-knife group and in 34 of 40 patients (85%) in the cold-knife group. No patient in the hot-knife group needed blood transfusion or hospitalization. Operating time was reduced by as much as 67% when the hot knife was used. Thirteen percent of the hot-knife patients developed stenosis of the external os. No patient in the hot-knife group developed recurrence within 2 years of surgery. CONCLUSION: Using a Teflon-coated hot knife for conization of the cervix produces adequate surgical margins and reduces blood loss and operating time over that with cold-knife conization. Long-term follow-up reveals no increase in cervical stenosis and demonstrates adequate cytologic smears in the hot-knife patients.

Solitary congenital self-healing reticulohistiocytosis.

Congenital self-healing reticulohistiocytosis (CSHR) was first described in 1973 by Hashimoto and Pritzker. Since then, both multiple and solitary forms have been described. We report a further case of solitary congenital self-healing reticulohistiocytosis. CSHR is a rare disorder which frequently presents a diagnostic dilemma in the newborn. Nodular forms of systemic Langerhans cell histiocytosis may present in a manner similar to CSHR. Because their differentiation on histopathological grounds is impossible, physical examination, laboratory investigations, and follow-up are necessary to ensure a lack of systemic involvement. Although previously thought to represent a rare variant of CSHR, solitary lesions of CSHR account for almost 25% of reported cases. A review of the literature relating to solitary CSHR, and a consideration of the differential diagnosis of a solitary congenital nodule, are also presented.

Sarcomatoid collecting duct carcinoma: a clinicopathologic and immunohistochemical study of five cases.

Sarcomatoid renal cell carcinoma is a well-known entity, but sarcomatoid collecting duct carcinoma has not been reported. We recently encountered five cases. The patients were men whose ages ranged from 59 to 82 years (mean age, 68 years). All presented with gross hematuria and three had abdominal fullness. Tumor size ranged from 6 to 9 cm in greatest dimension. The Fuhrman's nuclear grade of the carcinomatous components was 3 in three cases and 4 in two. The sarcomatoid areas were composed of pleomorphic spindle cells forming a malignant fibrous histiocytomatous pattern in four cases and a fibrosarcomatous pattern in one. The immunohistochemical findings in the carcinomatous and sarcomatoid components were identical. Wide-spectrum anti-cytokeratin cocktail, epithelial membrane antigen, and vimentin antibodies demonstrated immunoreactivity, while Leu-M1 did not react in all five cases. Three of the five tumors were positive for Ulex europaeus agglutinin I lectin. One sarcomatoid carcinoma reacted with monoclonal antibody to high molecular weight keratins, and all five tumors reacted with a monoclonal antibody to low molecular weight keratins. Two patients died at 5 months and 13 months after diagnosis, two are alive with metastatic disease at 1 and 14 months, and one is alive with no evidence of disease at 36 months.

Adenomyoepithelioma of the breast. A spectrum of biologic behavior.

Adenomyoepitheliomas of the breast have been considered to have limited metastatic potential; axillary node metastasis has been reported, but there has been no report of distant metastasis. We report six cases, including two malignant adenomyoepitheliomas, one of which metastasized to the lung and brain. Patient age ranged from 26 to 63 years (mean 46). Primary tumors were solitary and measured 0.9-3.5 cm (mean 1.7). Five of six tumors presented as palpable masses. Two patients treated by local resection have no evidence of disease at 5 and 18 months' follow-up. Two patients treated by local resection had recurrences, one at 48 the other at 60 months. The fifth patient had a spindle-cell type adenomyoepithelioma diagnosed as malignant because of high mitotic rate and cytologic atypicality of the myoepithelial component. This patient was treated by mastectomy and has no evidence of disease at 18 months. The sixth patient, initially treated by local excision, had six local recurrences over 52 months treated by reexcisions, mastectomies, and radiation. A lung metastasis was resected at 54 months and brain metastases were identified at 60 months with death occurring at 64 months. Both malignant adenomyoepitheliomas had high mitotic rates [11-14/10 high-power fields (HPF)] diffusely throughout the tumors and foci of cytologically malignant cells. The malignant adenomyoepithelioma that metastasized had an infiltrative growth pattern that increased with successive local recurrences. The four other tumors had only isolated areas of mitotic activity (maximum 1-9/10 HPF) and minimal cytologic atypia. Immunohistochemistry performed on five of six cases confirmed dual epithelial/myoepithelial cell populations in all tumors examined, including the metastasis. Electron microscopic examination of the malignant adenomyoepithelioma that metastasized also confirmed dual epithelial/myoepithelial cell populations in a local recurrence and the lung metastasis. We conclude that there is a spectrum of behavior for breast adenomyoepitheliomas with potential for local recurrence and, rarely, distant metastasis.

Multicentric papillary-cystic neoplasm of the pancreas.

Two distinct papillary-cystic neoplasms were found in the pancreas of a young black woman. She presented to the hospital in her first trimester of pregnancy with the chief complaint of sharp right upper quadrant abdominal pain that radiated to the right shoulder. This was associated with jaundice, vomiting, and pruritus. On examination, a large, nontender, midepigastric abdominal mass was palpated. Serum liver enzyme levels were moderately to markedly elevated. An abdominal computed tomographic scan revealed a 9-cm solid and cystic mass located within the head of the pancreas with associated marked bile duct dilatation. A total pancreatectomy was performed. Gross examination of the specimen revealed two separate well-circumscribed tumors of unequal size. The larger one was found within the head of the pancreas and contained multiple hemorrhagic, cystic cavities. The smaller one, located within the tail, consisted primarily of solid tissue. Microscopic examination of both lesions revealed papillary-cystic neoplasms. To our knowledge, this is the first report of two synchronous papillary-cystic tumors of the pancreas and the first reported demonstration of the potential of this tumor for multicentricity.

Primary osteosarcoma of the lung. Report of two cases and review of the literature.

Two cases of primary osteosarcoma of the lung are presented. In one case, the radiologic, clinical, and cytologic findings led to a preoperative diagnosis of undifferentiated carcinoma of the lung. In the second case, a lung nodule was discovered during postchemotherapy follow-up in a patient with lymphoma. Fine needle aspiration in the second case showed lymphoma, and further chemotherapy was instituted; however, persistent growth of the nodule prompted a resection. Microscopic examination of the resected tumors in both cases revealed histologic features of high-grade osteosarcoma. Flow cytometric analyses of the primary tumors showed abnormal hyperdiploid deoxyribonucleic acid populations in accordance with those seen in high-grade malignant neoplasms. Immunohistochemical studies supported a mesenchymal origin for these tumors. These tumors shared clinical features with other reported cases of primary osteosarcoma of the lung such as large size at diagnosis, occurrence in older individuals, and aggressive behavior.

Interstitial cystitis treated with intravesical doxorubicin.

Three patients with interstitial cystitis diagnosed on the basis of clinical symptoms, classic endoscopic findings, and a typical histologic picture were treated with intravesical doxorubicin. All 3 patients showed remarkable improvement, as manifested by complete clearance of irritative bladder symptoms and healing of ulceration. Doxorubicin therefore may be the breakthrough drug for interstitial cystitis.

Identification of cryptosporidium in paraffin-embedded tissue sections with the use of a monoclonal antibody.

Recently a monoclonal antibody has been developed against the oocyst form of Cryptosporidium species for use in detecting the organism in fecal material. The authors undertook this study to determine if this antibody could be used in identifying Cryptosporidium species in paraffin-embedded tissue sections. Three biopsies showing Cryptosporidiosis as diagnosed by characteristic appearance by light and electron microscopy were selected from the surgical pathology files at the authors' institution. Paraffin sections were examined with the use of both an indirect immunofluorescence and an avidin-biotin-peroxidase technique. In all the cases, prominent staining of oocysts was seen; however, intracellular trophozoites did not react with the antibody. The authors conclude that this antibody can be used to identify Cryptosporidium species oocysts in tissue sections and that the antibody appears to be specific for the oocyst form only.