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51.
OBJECTIVE: The aim of this study was to explore the relevance of placental monoamine oxidase at the subcellular level in the etiology of the hyperserotonomic state in preeclampsia-eclampsia. STUDY DESIGN: The study was conducted on placentas from 20 normal pregnant women and 25 women with varied severity of preeclampsia-eclampsia. Placental serotonin and subcellular monoamine oxidase activity were determined. Histochemical localization of monoamine oxidase was done in placental sections and cell isolates. RESULTS: Placental serotonin increases with severity (rsystolic 0.84, rdiastolic 0.83) and monoamine oxidase decreases (rsystolic 0.86, rdiastolic 0.79). Placental monoamine oxidase showed marked changes in preeclampsia-eclampsia. Histochemical localization of monoamine oxidase showed diffused low activity evenly throughout the cytoplasm and nucleus of the syncytiotrophoblastic cells in preeclampsia-eclampsia; in contrast, normal placenta showed high activity in the cytoplasm without any activity in the nucleus of syncytiotrophoblastic cells. Detection of monoamine oxidase activity in nuclei of the placenta in preeclampsia-eclampsia is a novel finding. Monoamine oxidase activity at the subcellular level further strengthens this observation. A severity-dependent decrease was present in the nuclei of placentas with preeclampsia-eclampsia. The use of specific substrates and inhibitors revealed the presence of monoamine oxidase in mitochondria and nucleus. CONCLUSION: The study delineates an impaired catabolism of placental serotonin in preeclampsia-eclampsia. The novel appearance of monoamine oxidase in nuclei in proximity to its normal site and low activity resulting in a hyperserotonomic state may lead to preeclampsia-eclampsia. (Am J Obstet Gynecol 1996;175:1543-50.)  相似文献   
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The effects of morphine (10 mg/kg), nalorphine (1 and 10 mg/kg), and naloxone (1 mg/kg) were studied on the neocortical release of acetylcholine (ACh) in midpontine pretrigeminal transected rats. Morphine and, to a lesser extent, nalorphine decreased ACh release. Naloxone was ineffective alone but antagonized the action of morphine.Predoctoral fellow with scholarships from Laval University and Province of Quebec, Canada.This research was supported in part by USPHS grant MH-11846.  相似文献   
54.
BACKGROUND: One-year results of a randomized, double-blinded trial of Thymoglobulin versus Atgam for induction therapy in renal transplantation revealed that Thymoglobulin was associated with higher event-free survival (94% vs. 63%), less acute rejection (4% vs. 25%), and better graft survival. This article compares the safety and efficacy of Thymoglobulin versus Atgam induction through 5 years. METHODS: Review and analysis of clinic records and electronic databases. RESULTS: At 5 years, event-free survival (73% vs. 33%, P<0.001), graft survival (77% vs. 55%, P=0.047), and freedom from rejection (92% vs. 66%, P=0.007) were higher with Thymoglobulin versus Atgam. No additional cytomegalovirus (CMV) disease occurred after the first year with Thymoglobulin or Atgam (13% vs. 33%, P=0.056). There were two cases of posttransplant lymphoproliferative disorder (PTLD) with the Atgam arm and none with Thymoglobulin. Thymoglobulin was associated with profound lymphopenia at 2 years after transplantation. CONCLUSIONS: Thymoglobulin was associated with higher event-free survival, graft survival, and freedom from rejection without increased PTLD or CMV disease at 5 years compared with Atgam. The prolonged and profound lymphopenia may contribute to the long-term results associated with Thymoglobulin.  相似文献   
55.
The authors report a rare case of renal failure secondary to abdominal cyst in a newborn girl. The clinical presentation was one of a largely distended abdomen coupled with anuria. The histopathologic and clinical findings suggest mesenteric cyst causing renal failure by mass effect.  相似文献   
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Seventeen children with congenital generalized lipodystrophy or Berardinelli-Seip Congenital Lipodystrophy (BSCL) from 12 consanguineous sibships were observed in Oman. All children had widespread absence of adipose tissue from infancy together with apparent muscle hypertrophy and hepatomegaly. They did not appear to represent a single homogenous entity, and it was possible to subclassify the cases into two distinct groups. In the first group of seven cases, the features were similar to other published cases with acanthosis nigricans, raised insulin levels, and insulin resistance. In this group, there was an association between the degree of acanthosis nigricans and the severity of the disorder. Molecular analysis of these cases showed homozygosity at the BSCL2 locus on chromosome 11q13 in four of the seven cases. In the second group of ten cases, there were striking abnormalities in both skeletal and nonskeletal muscle. Reduced exercise tolerance and percussion myoxedema were observed in skeletal muscle, while infantile hypertrophic pyloric stenosis, prominent veins (phlebomegaly), disturbance of cardiac rhythm, and cardiomyopathy were observed in nonskeletal muscle. There was evidence against homozygosity in some cases for the known loci for BSCL, and this group may represent a new clinical syndrome with lipodystrophy at a different genetic location.  相似文献   
58.
PURPOSE: To report childhood infection with Baylisascaris procyonis (raccoon round worm) manifesting as diffuse unilateral subacute neuroretinitis (DUSN) and choroidal infiltrates in association with neurologic disease (neural larva migrans).METHOD: Observational case series, one with eye manifestations of DUSN, the other with choroidal infiltrates, both with severe neurologic degeneration. RESULTS: Indirect immunofluorescence assays on serum and cerebrospinal fluid were positive for B. procyonis in one and serially positive and increasing in the other. Both children had a history of pica and raccoon exposure. CONCLUSIONS: Baylisascaris procyonis infection is associated with two cases of severe neurologic degeneration with ocular lesions: DUSN and choroidal infiltrates. Although B. procyonis is known to cause DUSN, these cases indicate that concomitant ocular migration may accompany neural larva migrans. These are the third and forth cases in the US literature of neural larva migrans due to B. procyonis with eye findings.  相似文献   
59.
We report the MRI features in a series of four patients with primary angiitis of the central nervous system (PACNS). Based on MRI features, clinical presentation, paraclinical investigations and laboratory tests, including cerebrospinal fluid (CSF) analysis, various differentials were considered. In two patients with MRI findings of cortical, subcortical and deep white matter lesions, lack of mass effect, focal areas of bleed and heterogeneous parenchymal, leptomeningeal or pial enhancement and a normal magnetic resonance angiography, a differential diagnosis of primary angiitis of the CNS was also considered. In all patients, an open brain biopsy was advised to establish a definitive diagnosis of PACNS. Here, we briefly discuss the MRI features, correlation with clinical presentation and paraclinical parameters for the diagnosis of this entity. We also briefly review the literature.  相似文献   
60.
We present our experience in the endoscopic management of upper aerodigestive tract lesions caused by caustic agents. Between 1985 and 2000, 112 patients with upper airway and digestive tract lesions due to caustic agents were treated at the Airways Endoscopic Surgery Unit of Padua Hospital: 44 were male and 68 were female, and the median age was 42.6 years. A retrospective statistical analysis of our case series was made to evaluate the factors that most influenced the severity of injuries and the outcome of treatment. All of the patients underwent videoendoscopic assessment. In 79 cases, the patients came under our observation in the acute phase, whereas 33 presented a picture of chronic lesions. Acute lesions were classified into 3 grades. All acute grade 1 lesions healed spontaneously. In the 32 patients with grade 2 lesions, endoscopic treatment based on removal of necrotic tissue, dilations, and cleansing of abnormal fibrin adhesions resolved the disease in 30 cases (94%). Nine patients (43%) with acute grade 3 lesions developed severe chronic lesions that required subsequent treatments. Rigid endoscopy with diode laser-assisted radial lysis was performed in 32 patients with chronic cicatricial lesions and was successful in 30 cases (94%). We reiterate the need for a standardized multidisciplinary protocol for treating lesions caused by caustic agents and emphasize the essential role of airway and digestive canal videoendoscopy in the diagnosis and treatment of both the acute lesions and chronic cicatricial sequelae.  相似文献   
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