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Background

Zenker’s diverticulum (ZD) may be treated with a variety of endoscopic or open surgical techniques; the choice of treatment depends partly on the size of the diverticulum. The purpose of this study was to correlate ZD measurements obtained preoperatively and during surgery.

Methods

From March 2006 to November 2008, 20 consecutive patients (19 males; median age 64.5 (range 37–88) years) with dysphagia secondary to ZD were enrolled for this study. All patients had preoperative barium radiography of the pharynx and esophagus, and diagnostic endoscopy. Ten patients underwent transoral stapling diverticulostomy and ten had open surgery. The depth of the ZD was measured on radiographic views, at endoscopy and during surgery, focusing on the distance from the top of the septum to the bottom of the pouch. The ZD dimensions obtained radiologically and endoscopically were compared with those found during surgery. Correlations and agreements between measurements were assessed using Pearson’s correlation coefficients and method-comparison analysis, respectively.

Results

The median depth of the ZD was 2.9?cm (mean 2.95?±?1.12?cm; range 1.5–6?cm), 3.0?cm (mean 3.24?±?1.27?cm; range 1.7–6.8?cm), and 3.0?cm (mean 2.99?±?1.01?cm; range 1.5–6?cm) when measured during surgery, radiology, and endoscopy, respectively. The correlation and agreement between the radiographic and surgical ZD measurements were good, whereas those between the endoscopic and surgical measurements were poor.

Conclusions

These findings confirm that preoperative barium radiography is mandatory in order to choose the most appropriate surgical treatment for ZD.  相似文献   
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Preeclampsia is a disorder of hypertension and proteinuria that affects 6 - 8% of normal pregnancies. Recent research has revealed many molecular mechanisms that may contribute to systemic endothelial dysfunction, glomerular capillary endotheliosis, dysregulation of the glomerular filtration apparatus, and podocyte loss. An ischemic placenta elaborates soluble FMS-like tyrosine kinase 1 (sFlt-1), a soluble receptor for vascular endothelial growth factor (VEGF). A variety of mediators, including nitric oxide, Angiotensin II receptor autoantibodies (AT1AA), and endothelin-1 may serve to maintain placental ischemia and systemic endothelial dysfunction. Endothelin-1 and decreased vascular endothelial growth factor may adversely affect overall expression and distribution of podocyte foot process proteins, leading to proteinuria. Podocyte derangements may lead to podocyte apoptosis and loss, as evidenced by the detection of live podocytes and podocyte products in the urine of preeclamptic women. In this review, we explore recent research elucidating the interactions of placenta, endothelium, and podocyte leading to the clinical syndrome of preeclampsia.  相似文献   
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Neuronal nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels widely expressed throughout the mammalian brain, including bulbar and spinal motor neurons. They are involved in neuroprotection and in control of release of many neurotransmitters, including glutamate. Previous data raised the hypothesis that rare variants in the region coding the intracellular loop subunits of nAChRs might represent one of several genetic risk factors for SALS. The aim of present study was to replicate the study in an independent cohort of ALS patients. We analysed 718 sporadic ALS patients from five Italian ALS centres and 1300 ethnically matched controls. We focused primarily on CHRNA4, encoding α4 subunit, since most mutations were previously detected in this gene. We observed a significant association between CHRNA4 mutations and ALS (OR 2.91; 95% CI 1.4080-6.0453; p =?0.0056). Most mutations detected in patients were not present in the dbSNP134 and in 3500 ethnically matched control chromosomes and affected evolutionary conserved amino acid residues. In conclusion, the present data confirm that CHRNA4 variants are overrepresented in SALS strengthening the hypothesis can they act as predisposing genetic factors for SALS.  相似文献   
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