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41.
Dissecting aneurysms of coronary arteries are a rare finding and have never been reported in a cardiac allograft. We found two spontaneous dissecting aneurysms on the middle third of both the left anterior descending and the right coronary arteries in a female cardiac transplantation recipient. She died 43 days after cardiac transplantation after developing human cytomegalovirus pneumonia and pancreatitis. Dissecting coronary aneurysms, microfoci of subendocardial coagulative necrosis, and area of subepicardial dystrophic calcifications were discovered at necropsy examination.  相似文献   
42.
The biodegradability of solution-cast films of poly(D (–)-3-hydroxybutyrate) (PHB) blended with the melt-compatible component atactic poly(epichlorohydrin) (aPECH) was investigated. A bacterium which produced extracellular enzymes that degraded PHB even when blended with aPECH was isolated, and tentatively designated as Aureobacterium saperdae. The growth rate of A. saperdae decreased with increasing aPECH content in the blend, up to films containing 60 wt.-% aPECH, at which composition growth was completely inhibited. The decrease in the bacterial growth rate could be due to the dilution of PHB molecules on the blend film surface caused by the presence of aPECH molecules. At the stationary phase of bacterial growth the percentage of weight loss of blend films decreased with increasing aPECH fraction, which was probably due to the lower accessibility of PHB when blended with aPECH. During the bacterial growth only PHB was metabolized, whereas neither degradation nor abiotic release of aPECH was detected for blend films.  相似文献   
43.
Islet autoimmunity precedes type 1 diabetes onset. We previously found that islet autoimmunity rarely starts before 6 months of age but reaches its highest incidence already at ∼1 year of age. We now examine whether homeostatic expansion and immune competence changes seen in a maturating immune system may account for this marked variation in islet autoimmunity risk in the first year of life. We found naïve proinsulin- and GAD65-responsive T cells in cord blood (CB) of healthy newborns, with highest responses observed in children with type 1 diabetes-susceptible HLA-DRB1/DQB1 genotypes. Homeostatic expansion characteristics with increased IL-7 concentrations and enhanced T-cell responsiveness to IL-7 were observed throughout the first year of life. However, the ability of antigen-presenting cells to activate naïve T cells was compromised at birth, and CB monocytes had low surface expression of CD40 and HLA class II. In contrast, antigen presentation and expression of these molecules had reached competent adult levels by the high incidence age of 8 months. We propose that temporal changes in islet autoimmunity seroconversion in infants are a consequence of the changing balance between homeostatic drive and antigen presentation competence. These findings are relevant for early prevention of type 1 diabetes.Type 1 diabetes is an autoimmune disease resulting from the destruction of insulin-producing pancreatic islet β-cells. The disease is associated with the presence of autoantibodies and antigen-experienced T cells against islet autoantigens (1). Autoreactive T cells can be identified in patients with type 1 diabetes and nondiabetic control subjects (2). Patients have naïve and memory autoantigen-responsive CD4+ and CD8+ T cells, whereas autoreactive T cells identified in control subjects appear to be confined to the naïve T-cell compartment (3).The presence of autoimmunity against islet antigens is detected by measuring autoantibodies in the blood and it is assumed that seroconversion to islet autoantibody positivity is accompanied by activation of islet autoreactive T cells. Seroconversion is rare prior to 6 months of age but rapidly reaches a peak incidence at ∼1 year of age in genetically susceptible children (4,5). We postulated that a switch from relative protection to susceptibility to islet autoimmunity may be driven by physiological changes in immune competence and homeostatic mechanisms in the first years of life. T cells at birth are mostly naïve, thereby requiring strong signals through the T-cell receptor and costimulation for priming. On the other hand, neonates have active homeostatic mechanisms, including a high cell cycle rate and an increased serum IL-7 concentration favoring clonal expansion (68). Here, we compare responsiveness and immune competence of circulating T cells and antigen-presenting cells (APCs) during periods of relative protection (birth) and susceptibility (8 months) to islet autoimmunity. Both periods are characterized by the presence of autoantigen-responsive naïve T cells and T cells that are highly sensitive to homeostatic expansion mechanisms. However, the activation of naïve T cells is compromised at birth and appears fully competent at 8 months of age. We predict, therefore, that the combination of an HLA genotype–determined islet autoreactive naïve T-cell population, homeostatic expansion mechanisms, and immune competence provides a highly favorable environment for islet autoimmunity and, in part, determines the high incidence of seroconversion observed at ∼1 year of age. This has implications for early prevention of islet autoimmunity.  相似文献   
44.
Introduction  The aim of the present analysis was to study the safety and efficacy associated with reanimation in facial nerve palsy by the endoscopically assisted multiple muscle transposition and lifts (EMTL). Patients and Methods  The study sample included all patients who had undergone a facial reanimation by EMTL procedure from September 2015 to May 2019. The patients were analyzed retrospectively, with more than 1 year of follow-up, and were evaluated in terms of functional-aesthetic results and postoperative complications. The outcome was evaluated with the Sunnybrook scale. Results  Fourteen patients were included in the present study. They were all inveterate palsies with minimum 4 years from the initial injury. The preoperative Sunnybrook score ranged from 0 to 5 and the postoperative ranged from 30 to 65. Spontaneous smile achievement was obtained in 10 patients and only mild restoration in one patient. The scar and static correction were satisfactory in all patients. Eye protection was improved in all cases with some form of active blinking in six cases. Conclusion  This study showed that facial palsy correction with EMTL procedure offers a promising alternative treatment for patients with facial palsy not suitable for microsurgical muscle transposition.  相似文献   
45.
Cardiomyopathy is a frequent complication in propionic acidemia. It is mostly rapidly fatal and independent of the metabolic control or medical intervention. Here, we present the reversal of a severe cardiomyopathy after liver transplantation in a patient with propionic acidemia and the long‐term stability after ten years. Liver transplantation in patients with propionic acidemia may be considered a valid and long‐lasting treatment when cardiomyopathy is progressive and unresponsive to medical therapy.  相似文献   
46.
Growth hormone (GH) secretagogues are synthetic molecules with neuroendocrine but also cardiovascular activities mediated by specific GH secretagogue-receptors. The acute administration of hexarelin, a peptidyl GH secretagogue, increases left ventricular ejection fraction in normal subjects and even in patients with severe GH deficiency. We evaluated cardiac performances in patients with coronary artery disease after acute administration of hexarelin (2.0 microg/kg, i.v.) compared to that in patients given with GH-releasing hormone (GHRH; 2.0 microg/kg, i.v.), recombinant human (rh)-GH (10.0 microg/kg, i.v.) or placebo. Cardiac performance was studied in 24 male patients (age [mean +/- S.E.M.]: 59.5 +/- 1.1 years; body mass index: 24.6 +/- 0.9 kg/m(2); left ventricular ejection fraction: 57.2 +/- 1.4%) with coronary artery disease undergoing by-pass surgery during general anesthesia. Left ventricular ejection fraction, left ventricular end diastolic volume, cardiac index and cardiac output were evaluated by intraoperative omniplane transoesophageal echocardiography while wedge pressure, central venous pressure, mean arterial pressure and systemic vascular resistance index were evaluated by systemic and pulmonary arterial catheterization. RhGH, GHRH and placebo did not exert any hemodynamic effect while hexarelin induced a prompt (after +10 min) increase in left ventricular ejection fraction (P < 0.001), cardiac index (P < 0.001) and cardiac output (P < 0.001) lasting up to +90 min without any variation in left ventricular end diastolic volume. Accordingly, hexarelin induced a reduction of wedge pressure (P < 0.01). These changes occurred in the presence of increased mean arterial pressure (P < 0.05) and transient decrease of central venous pressure (P < 0.05 at +30 min only) but no change in systemic vascular resistance index. Heart rate after hexarelin was similar to that after placebo. Hexarelin induced a slight increase in GH levels which was similar to that after GHRH but far lower (P < 0.01) than that after rhGH. Thus, in patients with coronary artery disease undergoing by-pass surgery, the acute administration of hexarelin clearly improves cardiac performance without any relevant variation in systemic vascular resistance. The cardiotropic effect of hexarelin is not shared by GHRH or by rhGH, indicating that it is not mediated by the increase in circulating GH levels but more likely reflects activation of specific cardiovascular GH secretagogue receptors.  相似文献   
47.
The principal criterion for resectability of pancreatic carcinoma is the assessment of vascular involvement. In a prospective evaluation the ability of Spiral CT Angiography (CTA) to detect vascular involvement in 50 patients with pancreatic carcinoma, was proved; DSA was performed later in all patients. In 20 patients, without vascular involvement, a complete concordance was obtained. Of 30 patients with vascular involvement, there was complete concordance between CTA and angiography in 22 patients and discordance in 8 patients. CTA was superior in 2 cases with periadventitial infiltration and in 5 patients with splenoportal confluence thrombosis. DSA was superior in 1 case with infiltration of the superior mesenteric vein. After surgical evaluation, sensitivity of CTA and DSA was 97% and 77%, respectively, and the negative predictive values were 95% and 74%. As compared to DSA, CTA is more rapid and less invasive and can be considered the modality of choice for preoperative work-up of pancreatic neoplasm.  相似文献   
48.
The aim of this study was to extend our previous observations on the soy modulation of biochemical parameters in 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumors, by simultaneously investigating the expression of estrogen receptor-alpha (ERalpha), estrogen receptor-beta (ERbeta), progesterone receptor (PR), apoptosis, neu, and markers of cell proliferation, such as proliferating cell nuclear antigen (PCNA) by immunohistochemistry. The percentage of ERalpha positive tumors was 65.8% in masses from control animals, and significantly dropped to 36.8% in tumors from soy treated rats (P=0.010). The percentage of ERbeta positive tumors was 70.3% in masses from control animals vs. 50.0% in tumors from soy exposed animals (P=0.066). Moreover, the percentage of cases which were both ERalpha and ERbeta positive was significantly lower (17.6%) in soy treated than in control animals (51.3%) (P=0.006). The percentage of PR positive tumors was 34.2% in control animals vs. 2.6% in tumors from soy treated rats (P=0.0006). There were no statistically significant differences in the percentage of tumors positively stained for neu, apoptosis, or PCNA, in control vs. soy treated rats. However, when analyzing the reciprocal correlation among the different biochemical parameters we showed that, in treated animals, the majority of ERalpha positive tumors (91.7%) were also PCNA positive (P=0.036). The median percentage of PCNA positivity was significantly higher in ERalpha positive than in ERalpha negative tumors (25 vs. 5%) (P=0.0031). Moreover, an association was found between PCNA and neu status since all neu positive tumors were also PCNA positive (P=0.011).  相似文献   
49.
BACKGROUND: The aim of the Pandora project is to collect epidemiological information, check diagnostic and therapeutic pathways, and assess outcomes in a large hypertensive population. This report presents the results on patients enrolled in the study between 1997-1999. METHODS: Twenty-one general practitioners working in the Ravenna Local Health Service took part in the study. They were supplied with IBM compatible PCs and were trained to enter the patient's data (age, gender, familiarity for cardiovascular diseases, smoking, hospitalisations for cardiovascular disorders, diabetes, blood pressure, total cholesterolemia, creatininemia, antihypertensive therapy) on So.Ge.Pa. software. Cardiovascular risk factors were assessed according to the WHO - ISH joint committee recommendations. RESULTS: 2,608 treated hypertensive patients were enrolled, 65% of whom showed inadequate blood pressure control. The prevalence of inadequate BP control was higher in patients on multiple-drug antihypertensive therapy compared with those on monotherapy (71.9% vs. 47.9%), in older than in younger patients (70.7% vs. 56.1%) and in patients with three cardiovascular risk factors, or diabetes, or affected target organs, compared to those with two or less risk factors (72.4% vs. 63.3%), (p < 0.001 for all). 63.6% of patients were at risk for age, 36.6% for family history of cardiovascular diseases and 31.7% for severe hypercholesterolemia. CONCLUSIONS: BP control was inadequate in a large percentage of patients, but it was particularly unsatisfactory in the elderly and in patients with high cardiovascular risk. A cluster of cardiovascular risk factors was found in both adequately and inadequately controlled hypertensive patients.  相似文献   
50.
Epithelial abnormalities in cystic ovarian endometriosis.   总被引:6,自引:0,他引:6  
OBJECTIVE: To evaluate the prevalence of epithelial abnormalities in cystic ovarian endometriosis. METHODS: In this observational study, the specimens of 388 consecutive patients undergoing a surgical procedure whose final diagnosis included cystic ovarian endometriosis were histopathologically reviewed. The prevalence and patient characteristics of cases featuring epithelial metaplasia, hyperplasia, atypia, and endometrioid carcinoma arising in endometriosis were analyzed. RESULTS: The epithelial lining was evaluable in 339 cases. Left-sided cysts were significantly more common than right-sided ones (P < 0.0001). The observed prevalence was 12.1% for metaplasia, 9.4% for hyperplasia, 5.9% for atypia, and 4.1% for endometrioid carcinoma arising in endometriosis. Complex hyperplasia, but not simple hyperplasia or metaplasia, was significantly more common in cases with associated endometrioid carcinoma than in all other cases (P < 0.00001). A statistically significant trend for increasing age from normal epithelium to carcinoma was observed (P < 0.001). CONCLUSIONS: Epithelial abnormalities are a common finding in cystic ovarian endometriosis. Despite their clinical significance being still debated, complex hyperplasia and atypia can be associated with malignant transformation of endometriosis. Their observation in a surgical specimen, particularly in older patients, should indicate a careful examination of the entire lining of the cyst and a strict follow-up of the patient.  相似文献   
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