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OBJECTIVE: Intrauterine growth restriction (IUGR) is characterized by decreased placental perfusion. Low oxygen has been shown to increase soluble fms-like tyrosine kinase 1 (sFlt-1) expression in the human placenta. The objective of this study was to examine sFlt-1 expression in different types of IUGR pregnancies, including early-onset severe cases characterized by abnormal umbilical and uterine artery Doppler and discordant IUGR twins in which the normal cotwin represents the optimal control because both placentas share the same uterine environment. PATIENTS: Placentas from four subgroups were collected: early severe IUGR with umbilical artery absent end diastolic flow (n = 19), small for gestational age with normal uterine and umbilical artery Doppler (n = 11), severely growth-restricted dichorionic and monochorionic twins with abnormal umbilical artery Doppler (n = 9), preeclamptic twins (n = 3), and age-matched normal singletons (n = 19) and twin controls (n = 8). RESULTS: Expression of sFlt-1 mRNA and protein was significantly increased in IUGR placentas compared with small for gestational age and normal control placentas. sFlt-1 expression levels were also significantly greater in the small IUGR twin placentas from discordant twin pregnancies compared with the normal cotwin. In preeclamptic twins, sFlt-1 expression was increased in only one of the two placentas. CONCLUSIONS: Our results demonstrate that sFlt-1 expression is increased in severe IUGR placentas with abnormal umbilical artery Doppler of singletons and also in discordant IUGR twins. Reduced placental perfusion may contribute to the increased expression of sFlt-1 in IUGR pregnancies. Our data are compatible with differential sFlt-1 expression in placentas from discordant twins.  相似文献   
33.

Introduction

Dentofacial deformity refers to deviations from normal facial proportions and dental relationships that are severe enough to be handicapping. These anomalies involve many aspects of patient’s life and are sometimes also associated with a reduction of pharyngeal air space. Through orthognathic surgery it is possible to treat dentofacial deformities: this kind of surgery has several effects on skeletal structures and it has changes, as it is demonstrated by many studies, also on the upper airways. The orthognathic surgeries commonly used to correct this deformity are the mandibular setback and the maxillary advancement procedures. This study aims to evaluate the effects of maxillary and mandibular surgery on pharyngeal airway dimensions in skeletal class III malocclusions.

Materials and methods

This study considers 76 patients, treated between 2007 and 2013 by maxillary advancement (11 patients), maxillary advancement and mandibular setback (39 patients), maxillary advancement, mandibular setback and genioplasty reduction (26 patients). Cranial latero-lateral radiography was used to compare oropharyngeal airway morphologies before and 1 year after surgery.

Conclusion

The surgeon should consider bimaxillary surgery rather than mandibular setback surgery to correct a class III deformity to prevent the development of obstructive sleep apnea syndrome; in fact, bimaxillary surgery might have less effect on reduction of the pharyngeal airway than mandibular setback surgery only.  相似文献   
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One-hundred patients were included to evaluate the role of cerebral computed tomography (CT) to improve patient selection in asymptomatic internal carotid stenosis. Symptomatic patients were assigned to group A, asymptomatic patients to group B. A cerebral CT pattern A was observed in groups A and B in 60% and 20%, respectively (P < .0001). Between A and B groups, type 6 plaques were found, respectively, in 26.7% and 7.5% of patients (P = .01); a type 5 in 51.7% and 45% (P = .32) of patients; and a type 4 in 21.7% and 47.5% of patients, respectively (P = .006). Within B group, the association of CT pattern A and histological plaque level 4, 5, and 6 was, respectively, 25% (P = .15), 50% (P = .53), and 25% (P = .16). In group B, a 7-fold risk increase in CT pattern A was found in patients with level 6 plaque. In asymptomatic patients with high-risk plaque, a basal cerebral CT scan can be used as diagnostic tool to improve patient selection for intervention.  相似文献   
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36.

Purpose

Although hormones play fundamental roles in prostate growth, their clinical significance is not completely clear. Aims of present study were to assess whether testosterone and serum sex hormone levels are predictors of benign prostatic hyperplasia (BPH) or prostate cancer (PC) and to verify whether prostate cancer is associated with low testosterone levels, and to test association between testosterone levels and known prognostic factors in prostate cancer.

Methods

In 206 consecutive patients with benign prostatic hyperplasia or prostate cancer testosterone, follicle-stimulating hormone, luteinizing hormone and prolactin levels were tested and correlated with disease. In patients with prostate cancer, hormone levels were also correlated with known prognostic factors. Predictive value was assessed for age, prostate-specific antigen (PSA), PSA ratio, PSA density, prostate volume and serum sex hormone levels using multiple logistic regression analysis and receiver operating characteristic curves.

Results

Considering sex hormones, only testosterone levels were significantly lower in patients with prostate cancer than those with BPH; testosterone levels appear to be independent predictor of prostate cancer, enhancing predictive accuracy for BPH and PC. Testosterone levels do not seem to be associated with known clinical prognostic factors.

Conclusions

This study supports experimental findings that testosterone levels are predictor of prostate cancer and that prostate cancer is frequently associated with low testosterone levels. In the diagnostic work-up for prostate cancer, adding testosterone determination to PSA test may improve predictive accuracy.  相似文献   
37.
Respiratory chain disorders (RCDs) have been included in the differential diagnosis of adult-onset leukodystrophies. Here, we first report a 32-year-old female with an atypical, adult-onset, non-syndromic RCD due to a mitochondrial DNA deletion and manifesting as complicated ataxia. A ‘leukodystrophic’ pattern was found on brain MRI, but it was neither isolated nor predominant because of the presence of overt basal ganglia and infratentorial lesions, which led us to the proper diagnosis. Subsequently, we evaluated our series of patients with RCDs in order to verify whether a ‘leukodystrophic’ pattern with little or no involvement of deep grey structures and brainstem may be found in adult-onset RCDs, as reported in children. Among 52 patients with adult-onset RCDs, no case with a ‘leukodystrophic’ pattern was found, apart from three cases with a classical phenotype of mitochondrial neurogastrointestinal encephalopathy. In addition, no case of RCDs was found among six cases of adult-onset leukodystrophy of unknown origin and at least one feature suggestive of mitochondrial disease. The review of the literature was in agreement with these findings. Thus, we provide evidence that, unlike in children, RCDs should not be included in the differential diagnosis of adult-onset leukodystrophies, except when there are additional MRI findings or clinical features which unequivocally point towards a mitochondrial disorder.  相似文献   
38.
Journal of Neurology - Spinocerebellar ataxia type 14 (SCA14) is a dominantly inherited neurological disorder characterized by slowly progressive cerebellar ataxia. SCA14 is caused by mutations in...  相似文献   
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