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1.
BackgroundAlthough there are robust data about the pathophysiology and prognostic implications of left ventricular (LV) systolic dysfunction in patients with acquired heart disease, similar prognostic data about LV systolic dysfunction are sparse in the tetralogy of Fallot (TOF) population. The purpose of this study was to perform a meta-analysis of all studies that assessed the relationship between LV ejection fraction (LVEF) and cardiovascular adverse events (CAEs) defined as death, aborted sudden death, or sustained ventricular tachycardia.MethodsWe used random-effects models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).ResultsOf the 1,809 citations, 7 studies with 2,854 patients (age 28 ± 4 years) were included. During 5.6 ± 3.4 years' follow-up, there were 82 deaths, 17 aborted sudden cardiac deaths, and 56 sustained ventricular tachycardia events. Overall, CAEs occurred in 5.1% (144 patients). As a continuous variable, LVEF was a predictor of CAE (HR 1.29, 95% CI, 1.09-1.53, P = 0.001) per 5% decrease in LVEF. Similarly, LVEF < 40% was also a predictor of CAE (HR 3.22, 95% CI, 2.16-4.80, P < 0.001).ConclusionsLV systolic dysfunction was an independent predictor of CAE, and we observed a 30% increase in the risk of CAE for every 5% decrease in LVEF, and a 3-fold increase in the risk of CAE in patients with LVEF <40% compared with other patients. These findings underscore the importance of incorporating LV systolic function in clinical risk stratification of patients with TOF and the need to explore new treatment options to address this problem.  相似文献   
2.
We reviewed the clinical findings in 10 patients with lysyl hydroxylase deficiency (Ehlers-Danlos syndrome type VI) and report here the range of clinical severity in these patients. The distinctive feature common to all patients was muscle hypotonia with joint laxity in the newborn period, and moderate to severe kyphoscoliosis either was present or developed in almost all patients. Most patients also had some degree of skin abnormality observed in other types of Ehlers-Danlos syndrome: bruisability, abnormal scarring, and soft, distensible skin. These patients also are at risk for potentially catastrophic arterial rupture.  相似文献   
3.
The pathophysiology of akathisia still remains controversial. Iron deficiency was proposed to be an important factor in the development of akathisia. In the present study, it was aimed to compare levels of serum iron and linked variables in chronic akathisic (n=30), and non-akathisic patients (n=30) with schizophrenia and healthy controls (n=30) because of the controversy in the association of iron and akathisia. The Barnes Akathisia Scale for akathisia and Simpson-Angus Rating Scale for extrapyramidal side effects were used. Serum iron and linked variables and hematological profile of the patients and control subjects were determined. Serum iron levels were significantly lower both in akathisic and non-akathisic groups compared to the control group (P<0.001). Moreover, akathisic patients had significantly lower iron levels than non-akathisic patients (P<0.05). Total iron binding capacity was significantly higher in patients with akathisia compared to the control group (P<0.01). Although non-akathisic patients had a mild increase in total iron binding capacity, it was not statistically significant compared to the control group (P>0.05). Ferritin levels were determined to be significantly lower in both groups compared to the control group (P<0.01). In addition, there was a significant difference in ferritin levels between the patients with and without akathisia (P<0.05). In conclusion, our results support the hypothesis that an association between akathisia and iron metabolism exists.  相似文献   
4.
1. It has been demonstrated previously that conversion of big endothelin-1 (bET-1) to endothelin-1 (ET-1) is inhibited in vitro and in vivo by phosphoramidon. In addition, ET-1 binding sites and mRNA have been shown within the brain. Here we expand upon our previous observation that rat brain contains phosphoramidon-inhibitable endothelin converting enzyme (ECE) and show that this activity is not uniformly distributed throughout the brain. 2. ECE activity was detected by a bioassay which depended upon the 10,000 fold difference in potency between bET-1 and ET-1 as stimulants of guanosine 3':5'-cyclic monophosphate (cyclic GMP) accumulation in kidney epithelial (PK1) cells of the pig. Data were confirmed by specific enzyme-linked immunosorbent assay (ELISA) employing antibody directed against ET-1/3(17-21). 3. Following homogenization of the whole brain and ultracentrifugation the 100,000 g pellet contained greater than 4 times more ECE activity than the cytosol. Washing of the pellet with KCl (1 M) and extraction with the detergent CHAPS (20 mM) revealed a phosphoramidon-inhibitable ECE within the residual particulate fraction (nominally classified as the cytoskeletal fraction). Phosphoramidon (IC50, approx. 5 microM) or EDTA inhibited the conversion of bET-1 to ET-1 by the cytoskeletal fraction of rat brain by more than 60%.2+ 4. Following dissection of rat brain into olfactory bulb, cerebral cortex, striatum, hippocampus, cerebellum, midbrain (including thalamus), hypothalamus and medulla oblongata (including pons) the greatest ECE was detected in the hypothalamus and medulla oblongata.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
Whether the motility characteristics of hyperactivated spermatozoa were determined by stable changes at the axonemal level and whether the presence of cytosolic factors was required for the expression of these changes was investigated. Different degrees of sperm hyperactivation were produced in Percoll-washed spermatozoa after incubation for 1 hour to 3 hours at 37 degrees C in Ham's F-10 supplemented with human blood plasma or fetal cord serum. Decomplemented fetal cord serum induced the highest percentage of hyperactivation (19 +/- 3%), followed by human plasma (13 +/- 2%). Fetal cord serum that was not decomplemented did not induce a level of hyperactivation (1.7 +/- 0.2%) significantly different from control levels (0.9 +/- 0.2%). Dialyzed fetal cord serum induced intermediate levels of hyperactivation (6 +/- 1%). The motility characteristics of demembranated sperm models of hyperactivated spermatozoa induced by decomplemented fetal cord serum and nonhyperactivated spermatozoa were compared by videomicroscopy and computer-assisted digital image analysis. After demembranation with Triton X-100 and reactivation of motility by Mg. adenosine triphosphate (Mg.ATP), hyperactivated and nonhyperactivated spermatozoa showed similar motility characteristics. However, hyperactivated spermatozoa that were demembranated and reactivated in cytosolic extracts from hyperactivated spermatozoa had significantly higher (P less than 0.05) linear velocity (33 +/- 4 mu/sec) and lower linearity (0.23 +/- 0.04) than control spermatozoa that were demembranated and reactivated in control cytosolic extracts (velocity = 24 +/- 1 mu/sec; linearity = 0.32 +/- 0.02). The data suggest that the expression of hyperactivated motility requires interdependent changes at the axonemal and cytosolic levels.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
6.
Between 1971 and 1988, we examined 116 eyes of 58 patients with Gronblad-Strandberg syndrome in private practice and in the Retinal Department of the Eye Clinic, Faculty of Medicine, Ankara University. There was initial macular involvement in 79% of cases with angioid streaks. The most frequently encountered lesion, found in 53% of the cases, was choroidal neovascularization. Macular involvement had become bilateral in 80% of the cases after 12.5 months median follow up. Thirteen of the 50 eyes with choroidal neovascularization were treated by argon or red krypton laser photocoagulation. Vision decreased during follow-up in 15% of the 13 eyes treated whereas it decreased in 32% of the 69 eyes unsuitable for laser treatment.  相似文献   
7.
Pregnancy in acromegaly is a rather rare event since the fertility is reduced in acromegalic women. Besides, metabolic complications of acromegaly are harmful to both mother and fetus. Little is known about the outcome of pregnancy in acromegalic women. Here, we report seven cases of pregnancy out of 48 acromegalic women followed for 16 years. At diagnosis, five patients had macroadenoma, one patient had microadenoma and the size of the tumor was not documented in one patient. In one patient, acromegaly was initially diagnosed during pregnancy at 29 weeks. When she was 33 weeks, she developed pituitary apoplexy and had an emergency transsphenoidal resection of her macroadenoma during which she also had a cesarian section and delivered a healthy baby girl. In the remaining six patients, pregnancy occurred 6 to 64.5 months after the adenoma resection. Three patients received radiotherapy before getting pregnant. In three patients, pregnancy occurred during bromocriptine treatment and the drug was withdrawn. In one patient, pregnancy occurred during chronic octreotide treatment and therapeutic abortion was performed. In another patient, therapeutic abortion was performed because of uncontrolled disease. In the remaining four patients, there were neither worsening of symptoms nor tumor growth. All four patients gave birth to full-term healthy infants. Out of our seven patients, two developed gestational diabetes mellitus which was controlled with diet. None of the patients had coronary artery disease, hypertension or dyslipidemia. These cases show that pregnancy might be uneventful in acromegalic women when the disease is controlled with prior surgery and radiotherapy.  相似文献   
8.
Unicornuate uterus with a rudimentary horn is the rarest congenital anatomic anomaly of the female genital system, causing many obstetrical and gynecologic complications. The frequency of this pathology is approximately 1/100 000. A rudimentary horn usually develops following insufficient development of mullerian ducts. These patients present with dysmenorrhea, dyspareunia, and chronic pelvic pain because of endometriosis and rarely with acute abdominal symptoms following distention and torsion of the noncommunicating rudimentary horn. The case of a patient referred for acute abdomen after distention of a noncommunicating rudimentary horn is presented herein.  相似文献   
9.
A novel form of particulate guanylate cyclase tightly coupled by cytoskeletal components to receptors for heat-stable enterotoxin (ST) produced by Escherichia coli can be found in membranes from rat intestinal mucosa. Intestinal particulate guanylate cyclase was resistant to solubilization with detergent alone, with only 30% of the total enzyme activity being extracted with Lubrol-PX. Under similar conditions, 70% of this enzyme was solubilized from rat lung membranes. The addition of high concentrations of sodium chloride to the extraction buffer resulted in greater solubilization of particulate guanylate cyclase from intestinal membranes. Although extraction of intestinal membranes with detergent and salt resulted in greater solubilization of guanylate cyclase, a small fraction of the enzyme activity remained associated with the particulate fraction. This activity was completely resistant to solubilization with a variety of detergents and chaotropes. Particulate guanylate cyclase and the ST receptor solubilized by detergent retained their abilities to produce cyclic GMP and bind ST, respectively. However, ST failed to activate particulate guanylate cyclase in detergent extracts. In contrast, guanylate cyclase resistant to solubilization remained functional and coupled to the ST receptor since enzyme activation by ST was unaffected by various extraction procedures. The possibility that the ST receptor and particulate guanylate cyclase were the same molecule was explored. ST binding and cyclic GMP production were separated by affinity chromatography on GTP-agarose. Similarly, guanylate cyclase migrated as a 300,000-dalton protein, while the ST receptor migrated as a 240,000-dalton protein on gel filtration chromatography. Also, thiol-reactive agents such as cystamine and N-ethylmaleimide inhibited guanylate cyclase activation by ST, with no effect on receptor binding of ST. These data suggest that guanylate cyclase and the ST receptor are independent proteins coupled by cytoskeletal components in membranes of intestinal mucosa.  相似文献   
10.
We examined the pattern of tuberculosis (TB) transmission (i.e., reactivation versus recent transmission) and the impact of human immunodeficiency virus (HIV) infection in Harare, Zimbabwe. Consecutive adult smear-positive pulmonary TB patients presenting to an urban hospital in Harare were enrolled. A detailed epidemiological questionnaire was completed, and tests for HIV type 1 and CD4 cell counts were performed for each patient. Molecular fingerprinting of the genomic DNA recovered from cultures of sputum was performed by two molecular typing methods: spacer oligonucleotide typing (spoligotyping) and analysis of variable number of tandem DNA repeats (VNTRs). A cluster was defined as isolates from two or more patients that shared the same spoligotype pattern or the same VNTR pattern, or both. DNA suitable for typing was recovered from 224 patients. The prevalence of HIV infection was 79%. Of 187 patient isolates (78.6%) typed by both spoligotyping and analysis of VNTRs, 147 were identified as part of a cluster by both methods. By spoligotyping alone, 84.1% of patient isolates were grouped into 20 clusters. The cluster size was generally <8 patient isolates, although three large clusters comprised 68, 25, and 23 patient isolates. A total of 89.4% of the patient isolates grouped into 12 clusters defined by analysis of VNTRs, with 2 large clusters consisting of 127 and 13 patient isolates, respectively. Thirty-six percent of patient isolates with a shared spoligotype and 17% with a shared VNTR pattern were geographically linked within Harare, but they were not linked on the basis of the patient's home district. In a multivariate analysis, there were no independent predictors of clustering, including HIV infection status. Comparison with the International Spoligotype database (Pasteur Institute, Pointe a Pitre, Guadeloupe) demonstrated that our three largest spoligotype clusters are well recognized and ubiquitous in Africa. In this epidemiologically well characterized urban population with a high prevalence of HIV infection, we identified a very high level of strain clustering, indicating substantial ongoing recent TB transmission. Geographic linkage could be detected in a proportion of these clusters. A small group of actively circulating strains accounted for most of the cases of TB transmission.  相似文献   
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