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71.
Background: During labor, ephedrine is widely used to prevent or to treat maternal arterial hypotension and restore uterine perfusion pressure to avoid intrapartum fetal asphyxia. However, the effects of ephedrine on uterine blood flow have not been studied during uterine contractions. The purpose of the study was to assess the effects of ephedrine on uterine artery velocities and resistance index using the Doppler technique during the active phase of labor.

Methods: Ten normotensive, healthy parturients with uncomplicated pregnancies at term received intravenous ephedrine during labor to increase mean arterial pressure up to a maximum of 20% above their baseline pressure. Peak systolic and end-diastolic Doppler flow velocities and resistance indices were measured in the uterine artery before and immediately after administration of bolus intravenous ephedrine and after ephedrine washout. Umbilical and fetal middle cerebral arterial resistance indices and fetal heart rate were also calculated.

Results: After ephedrine administration, mean arterial pressure increased by 17 +/- 4%. End-diastolic flow velocity in the uterine artery at peak amplitude of uterine contraction was restored to 74% of the value observed in the absence of contraction. The systolic velocity was totally restored, and the uterine resistance index was significantly decreased, compared with the values in the absence of contraction. Between uterine contractions, ephedrine induced similar but less marked effects. Fetal hemodynamic parameters were not altered by ephedrine administration.  相似文献   

72.
Objective: The aim of this paper is to study clinical characteristics, surgical treatment and outcome of patients with solitary fibrous tumor of the pleura operated in our institutions in a 20-year period. Methods: Clinical records of all patients operated for solitary fibrous tumors of the pleura between 1981 and 2000 were reviewed retrospectively. Tumors were classified as malignant in the presence of at least one of the following criteria: (1) high mitotic activity; (2) high cellularity with crowding and overlapping of nuclei; (3) presence of necrosis; (4) pleomorphism; otherwise they were considered as benign. Results: Sixty patients (mean age 55 years) were operated in this period. None had asbestos exposure. Symptoms were present in 31 cases. Surgical approaches included thoracotomy (n=53), video-assisted thoracoscopy (n=6), and median sternotomy (n=1). Tumors originated from visceral pleura in 48 cases, from parietal, mediastinal or diaphragmatic pleura in seven, two and three cases, respectively; their mean diameter was 8.5 cm. Tumors could be resected with their implantation basis in 49 patients. In the remaining 11, extended resections were performed, including lung parenchyma (lobectomy, n=4, pneumonectomy, n=2), osteomuscular chest wall structures (n=2), diaphragm (n=2), and pericardium (n=1). Two postoperative deaths (due to myocardial infarction and pulmonary embolism, respectively) occurred. Tumors were pathologically benign in 38 cases and malignant in 22 cases. Mean follow-up was 88 months. Resection was complete in all the patients with benign tumors and no recurrence occurred. Resection was considered as complete in 21/22 malignant tumors. Local recurrence was observed in two cases. Both could be successfully managed by iterative exeresis (no extended resection had been initially performed). Metastatic disease (responsible for patient's death) was observed following the only incomplete resection. Actuarial 5- and 10-year survival rates were 97% for benign tumors and 89% for malignant ones. Conclusions: Surgical resection provided cure in all the patients with benign tumors. As insufficiency of exeresis is associated with all recurrences in malignant tumors, completeness of resection is in our experience the best prognostic factor in these forms.  相似文献   
73.
BACKGROUND: The sensitive cross-match (XM) techniques that have been introduced for clinical transplantation can detect anti-donor immune reactivity despite a negative standard National Institute of Health (NIH) cross-match. One of them uses anti-kappa human light chain globulins (AHG). But there is some discussion about the clinical consequences of a positive AHG-XM in the historical sera that became negative in the sera collected just before the transplantation (pretransplant sera). This study was intended to assess the risk of kidney graft failure associated with a positive historic but negative pretransplant AHG-XM in allosensitized patients having a negative historic NIH-XM. METHODS: This retrospective study includes 90 consecutive renal transplants in immunized patients performed at one center between 1985 and 1991. All of the patients had negative historical and pretransplant standard NIH lymphocytotoxic cross-matches and received the same immunosuppressive regimen. The AHG-XMs were done retrospectively using peak historic and sera collected on the day of the transplantation. RESULTS: The AHG cross-match (AHG-XM) was positive in 17 patients, although the standard NIH cross-match was negative. Fourteen of them had a positive historical but negative pretransplant AHG-XM. The actuarial graft survival in this group of 14 patients was 100% at 1 year and 78% at 9 years compared with 90 and 67%, respectively, in patients with negative historical AHG-XM. In addition, the number of rejection episodes per patient as well as renal function at 1, 2, and 5 years were similar in the two groups. IgG anti-donor HLA class I accounted for the XM positivity in 12 of the 14 patients; most rapidly lost all antibody reactivity by NIH technique in an average time of 8 months before the transplantation. In conclusion, this study suggests that transplant patients having a negative historic NIH-XM but a positive historic AHG-XM may not be at high risk of graft failure especially if there is a well-documented sera history showing a marked decrease in PRA level before transplantation and a negative pretransplant AHG-XM.  相似文献   
74.

OBJECTIVE

The response of ventromedial hypothalamic (VMH) glucose-inhibited neurons to decreased glucose is impaired under conditions where the counterregulatory response (CRR) to hypoglycemia is impaired (e.g., recurrent hypoglycemia). This suggests a role for glucose-inhibited neurons in the CRR. We recently showed that decreased glucose increases nitric oxide (NO) production in cultured VMH glucose-inhibited neurons. These in vitro data led us to hypothesize that NO release from VMH glucose-inhibited neurons is critical for the CRR.

RESEARCH DESIGN AND METHODS

The CRR was evaluated in rats and mice in response to acute insulin-induced hypoglycemia and hypoglycemic clamps after modulation of brain NO signaling. The glucose sensitivity of ventromedial nucleus glucose-inhibited neurons was also assessed.

RESULTS

Hypoglycemia increased hypothalamic constitutive NO synthase (NOS) activity and neuronal NOS (nNOS) but not endothelial NOS (eNOS) phosphorylation in rats. Intracerebroventricular and VMH injection of the nonselective NOS inhibitor NG-monomethyl-l-arginine (l-NMMA) slowed the recovery to euglycemia after hypoglycemia. VMH l-NMMA injection also increased the glucose infusion rate (GIR) and decreased epinephrine secretion during hyperinsulinemic/hypoglycemic clamp in rats. The GIR required to maintain the hypoglycemic plateau was higher in nNOS knockout than wild-type or eNOS knockout mice. Finally, VMH glucose-inhibited neurons were virtually absent in nNOS knockout mice.

CONCLUSIONS

We conclude that VMH NO production is necessary for glucose sensing in glucose-inhibited neurons and full generation of the CRR to hypoglycemia. These data suggest that potentiating NO signaling may improve the defective CRR resulting from recurrent hypoglycemia in patients using intensive insulin therapy.Intensive insulin therapy significantly reduces the onset and progression of hyperglycemia-related complications in patients with type 1 and advanced type 2 diabetes. However, intensive insulin therapy also causes a clinically adverse effect: hypoglycemia (1). Powerful neuroendocrine and autonomic counterregulatory mechanisms protect the brain from hypoglycemia (2,3). These protective mechanisms, known as the counterregulatory response (CRR) to hypoglycemia, involve the release of hormones (e.g., glucagon, epinephrine) that restore euglycemia by stimulating hepatic glucose production and inhibiting peripheral glucose uptake (3). Although the physiology of the CRR is well understood, the underlying cellular mechanisms by which the brain senses hypoglycemia and initiates the CRR remain elusive.During hypoglycemia, central and peripheral glucose sensors detect declining glucose levels (4). In the brain, the ventromedial hypothalamus, which includes the arcuate nucleus and the ventromedial nucleus (VMN), is important in the initiation of the CRR (57). This region contains specialized glucose-sensing neurons (GSNs). Ventromedial hypothalamic (VMH) GSN electrical activity is regulated by physiologically relevant changes in extracellular glucose levels (811). Glucose-excited neurons decrease, whereas glucose-inhibited neurons increase, their input resistance, membrane potential, and action potential frequency when extracellular glucose is reduced (10). Many studies suggest that VMH glucose-inhibited neurons play a critical role in the control of the CRR (4). For example, the response of VMH glucose-inhibited neurons to decreased glucose is impaired under conditions where the CRR is impaired (e.g., recurrent hypoglycemia) (12,13).Nitric oxide (NO) is a gaseous messenger produced by NO synthase (NOS). Two classes of NOS have been identified in the brain: the inducible NOS (iNOS) and the constitutive NOS, which includes the neuronal NOS (nNOS) and endothelial NOS (eNOS) isoforms (14). Hypothalamic NO is involved in the regulation of food intake and glucose homeostasis (1518). In support of this, we have recently shown that VMH glucose-inhibited neurons produce NO via nNOS in response to decreased extracellular glucose levels (19,20). Therefore, in this study, we test the hypothesis that NO production by VMH glucose-inhibited neurons is necessary for the CRR to hypoglycemia. We tested this hypothesis using a combination of in vivo and in vitro techniques in wild-type rats and mice as well as in transgenic nNOS and eNOS knockout mice.  相似文献   
75.
The objective of this study was to identify clinical and demographic factors associated with incontinence-related quality of life (QoL) in 655 women with stress urinary incontinence who elected surgical treatment. The following factors were examined for their association with QoL as measured with the Incontinence Impact Questionnaire (IIQ): number of incontinence (UI) episodes/day; self-reported type of UI symptoms (stress and urge); sexual function as measured by the Prolapse/Urinary Incontinence Sexual Questionnaire; symptom bother as measured by the Urogenital Distress Inventory; as well as other clinical and sociodemographic factors. A stepwise least-squares regression analysis was used to identify factors significantly associated with QoL. Lower QoL was related to the greater frequency of stress UI symptoms, increasing severity, greater symptom bother, prior UI surgery or treatment, and sexual dysfunction (if sexually active). Health and sociodemographic factors associated with lower incontinence-related QoL included current tobacco use, younger age, lower socioeconomic status, and Hispanic ethnicity. Supported by cooperative agreements from the National Institute of Diabetes and Digestive and Kidney Diseases, with additional support from the National Institute of Child Health and Human Development and the Office of Research on Women’s Health, National Institutes of Health.  相似文献   
76.
Lysosome-associated membrane protein-2 deficiency (LAMP-2 deficiency), or Danon disease, is a rare X-linked lysosomal disease characterized by cardiomyopathy, vacuolar myopathy, and mental retardation. Less than 20 families with mutations of the Lamp-2 gene have been reported. We describe a family from Sardinia with eight affected patients (4 females and 4 males) and a novel mutation in exon 2 of the Lamp-2 gene (c.102_103delAG). Females developed isolated cardiomyopathy in adulthood, whereas males presented with cardiomyopathy, myopathy, and mental retardation before the age of 20 years. Cardiomyopathy was lethal in three females in their 40s and in three males before the age 20 years. One patient was successfully treated by heart transplantation with more than 5-year follow-up. This study demonstrates that Danon disease is a frequently fatal condition that is potentially treatable with heart transplantation.  相似文献   
77.
BACKGROUND: Although we have shown in three out of five patients with Huntington's disease that motor and cognitive improvements 2 years after intracerebral fetal neural grafts are correlated with recovery of brain metabolic activity in grafted striatal areas and connected regions of the cerebral cortex, neural grafts are not known to have protective effects on the host brain per se. We undertook long-term follow-up of previously reported patients with the disease to ascertain the nature and extent of any secondary decline after grafting. METHODS: Five patients with Huntington's disease from our pilot study were assessed annually with the unified Huntington's disease rating scale, neuropsychological tests, and MRI, for up to 6 years after neural grafting. Resting cerebral activity was recorded at 2 and 6 years. FINDINGS: Clinical improvement plateaued after 2 years and then faded off variably 4-6 years after surgery. Dystonia deteriorated consistently, whereas chorea did not. Cognitive performance remained stable on non-timed tests, whereas progression of motor disability was shown by deterioration on timed tests. Hypometabolism also affected the brain heterogeneously, sparing the benefits in the frontal cortex and at the precise location of the grafts, but showing a progressive deterioration in other areas. Two patients who had no benefit from grafting at 2 years continued to decline in the same way as non-grafted patients. INTERPRETATION: Neuronal transplantation in Huntington's disease provides a period of several years of improvement and stability, but not a permanent cure for the disease. Improvement of the surgical procedure and in patient selection could improve the therapeutic value, but neuroprotective treatment seems to be unavoidable in the disease.  相似文献   
78.

Background  

Incidental gallbladder cancer (GBC) is frequently discovered on the specimen when cholecystectomy for a benign disease is performed. The objective of the present study was to assess the management of incidental GBC patients in a French registry.  相似文献   
79.
Exogenous lipoid pneumonia: HRCT, MR, and pathologic findings   总被引:3,自引:0,他引:3  
The objective of this study was to describe high-resolution CT (HRCT) and MR findings of exogenous lipoid pneumonia and to correlate them with pathologic findings. A retrospective review of the medical records of our institution revealed seven patients with a diagnosis of lipoid pneumonia based on clinical data, chest films, bronchoalveolar lavage, and follow-up. Both HRCT and MR imaging were reviewed by two readers. Pathologic examination of the resected specimen or surgical biopsies were also reviewed in the four available cases. The HRCT findings were pulmonary consolidations (n = 6) with fatty (n = 3) or unspecific but low attenuation values (n = 3), areas of ground-glass opacities (n = 5), septal lines, and centrilobular interstitial thickening (n = 5). In five of the seven cases, a crazy-paving pattern of various spread was also present, either isolated (n = 1) or surrounding a pulmonary consolidation. In two cases traction bronchiectasis and cystic changes consistent with fibrosis were seen. At MR imaging (n = 2) a pulmonary consolidation of high signal intensity on T1-weighted image consistent with lipid content was present in one case. Pathologic examination (n = 4) showed the coexistence of lobules with lesions of various ages, sometimes in contiguous lobules, within the same patient. Recent lesions were those with alveolar fill-in by spumous macrophages and almost normal alveolar walls and septae. In more advanced lesions, lobules were filled in with larger vacuoles often surrounded by inflammatory infiltrates of alveolar walls, bronchiolar walls, and septa. The oldest lesions were characterized by fibrosis and parenchymal distortion around large lipid-containing vacuoles. The HRCT findings reflect pathologic findings in exogenous lipoid pneumonia. Although non-specific, consolidation areas of low attenuation values and crazy-paving pattern are frequently associated in exogenous lipoid pneumonia and are indicative of the diagnosis. Received: 24 July 1998; Revision received: 30 December 1998; Accepted: 1 February 1999  相似文献   
80.
BACKGROUND: The true relevance of allosensitization in patients benefiting from left ventricular assist device (LVAD) as bridge to transplant (BTT) is still debated. Available registry data referred to numerous devices precluding LVAD-specific analysis. Therefore, we studied all patients with Novacor LVAD prior to transplantation. METHODS: From 1985 to 2006, 37 Novacor LVADs were implanted as BTT, with 30 patients surviving to transplantation (81%). Post-LVAD sensitization was determined for anti-HLA-class I and class II IgGs. Study endpoints were overall survival and/or graft loss, > or =3A cellular rejection and chronic allograft vasculopathy (CAV). The results from LVAD patients were compared to non-LVAD primary heart transplant recipients (n=318). RESULTS: After LVAD insertion, 5 out of 27 patients available for analysis developed anti-HLA antibodies (18.5%). The mean anti-HLA titer after Novacor LVAD implantation was 14% [SD 31]. Actuarial 5- and 10-year patient/graft survival for LVAD and non-LVAD transplant recipients were 73% and 55%, and 70% and 55%, respectively (p=NS). Overall prevalence of rejection > or =3A was 23.3 % (LVAD group) and 18.9% (non-LVAD group) (p=NS). At follow-up, the respective incidence of CAV was 8% (LVAD group) and 32.4% (non-LVAD group) (p<0.01). However, mean follow-up was significantly different for LVAD and non-LVAD patients, 46 vs 90 months (p<0.001). CONCLUSION: In this study, allosensitization occurred infrequently after Novacor LVAD implantation. Secondly, analysis of outcome variables shows that Novacor-LVAD BTT patients can anticipate similar survival to non-LVAD patients, thus minimizing the impact of allosensitization after LVAD implantation.  相似文献   
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