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Purpose

The pentose phosphate pathway (PPP) has been shown to play an important role in the metabolism of cancer cells. The transketolase-like 1 gene (TKTL1) encodes an enzyme representing an essential component of this pathway. Its expression has been demonstrated to correlate with stage and outcome in various tumors. The aim of the present study was to assess expression patterns and the prognostic role of TKTL1 in muscle-invasive bladder cancer (MIBC).

Patients and methods

The expression of TKTL1 was assessed in a tissue microarray consisting of histopathologically benign and malign tissue of 112 patients who underwent radical cystectomy due to MIBC. Cytoplasmatic and nuclear expression were assessed by immunohistochemistry and compared separately with clinicopathologic parameters and outcome.

Results

Cytoplasmatic expression of TKTL1 was exclusively present in tumor tissue. In contrast, the proportion of nuclei positive for TKTL1 was higher in histopathologically benign tissue compared with malign tissue. No correlation was observed between cytoplasmatic or nuclear TKTL1 expression and tumor stage, grade or the presence of metastases. Patients with lymph node involvement showed a decreased frequency of cytoplasmatic expression compared with node-negative patients (p = 0.01). However, no further correlation was observed between the expression of TKTL1 and clinical outcome of patients.

Conclusions

The present study shows that the cytoplasmatic expression of TKTL1 is specific for MIBC tissue compared with histopathologically benign urothelium. This specific expression is present in a subgroup of MIBC potentially identifying patients with activated PPP suitable for a targeted inhibition of sugar metabolism. In contrast to other malignancies, TKTL1 shows no prognostic significance in MIBC.

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One of the aims of laparoscopic surgery is to improve upon the results obtained by open surgery. This clearly appears to have been achieved in bariatric surgery. Two-dimensional (2-D) systems have been used to date, though new 3-dimensional (3-D) technologies have been introduced in an attempt to improve surgeon vision and thus increase the safety of the surgical techniques. Sixty obese patients underwent sleeve gastrectomy using a device equipped with 3-D optics allowing surgery to be viewed by the surgeon in 3 dimensions by using a specific monitor and wearing appropriate glasses. The mean patient age was 48.1 years. The mean weight was 114 kg (range, 92–172), with a mean body mass index (BMI) of 44 ± 5.21 kg/m2. All surgeries were performed using the 3-D system, with a mean surgical time of 71 ± 49.6 minutes and a mean hospital stay of 3.0 ± 1.2 days. Only 1 intraoperative complication was recorded: retroperitoneal bleeding on insertion of the optical trocar. Over a mean follow-up period of 12 months, the mean body weight of the patients was 88 kg (range, 71–121), with a BMI of 30.56 ± 3.98 kg/m2 and a percentage excess weight loss of 68.14% ± 7.89%. There was clear improvement of both the blood pressure and glucose levels. Three-dimensional sleeve gastrectomy is safe, viable, and fully reproducible compared with 2-D surgery, improving visualization of the surgical field, safety, and surgeon convenience. Randomized studies involving larger patient samples are needed for the comparison of results.Key words: 3-D laparoscopy, Bariatric surgery, Metabolic surgeryIn recent years, laparoscopic surgery has become clearly indicated in bariatric and metabolic surgery. This surgical technique has made it possible to reduce morbidity and mortality in comparison with conventional open surgery, and to shorten hospital stay. In addition to the usual 5-trocar technique, laparoscopic surgery has also produced satisfactory results with the single-port approach, which is regarded as less invasive and affords equivalent outcomes and improved aesthetic results.More recently, the possibility of using three-dimensional (3-D) surgery has been considered. The film Avatar (James Cameron, 2006) represented a starting point for a number of multinational medical engineering companies who launched projects that now allow us to use 3-D laparoscopic systems. This new technology offers the perception of depth, which was not previously available.Sleeve gastrectomy is one of the surgical techniques presently used to treat obesity. It was initially regarded as first-step surgery in patients with a high body mass index (BMI), before performing biliopancreatic diversion. Sleeve gastrectomy is currently considered to be a restrictive technique that can be used as a sole option in morbid obesity, even when accompanied by diabetes mellitus, as contemplated by the International Sleeve Gastrectomy Expert Panel Consensus of 2011.Three-dimensional laparoscopic sleeve gastrectomy requires 5 ports, like the two-dimensional (2-D) laparoscopic technique, and one of them must be enlarged to extract the sectioned stomach. However, 3-D visualization is very useful in all the surgical steps, as it improves spatial orientation and can increase the safety of the surgical technique.The present study analyzes the results of 3-D laparoscopic sleeve gastrectomy after a short 1-year follow-up period, with a view to evaluating its safety and feasibility in patients with severe or morbid obesity and type 2 diabetes.  相似文献   
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Journal of Neurology - Little is known about metabolic changes in progressive supranuclear palsy. Goals of the present study are to: (1) investigate whether early progressive supranuclear palsy is...  相似文献   
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Neurological Sciences - Autoimmune autonomic ganglionopathy is a rare, immune-mediated disorder associated with anti-ganglionic α3-subunit nicotinic acetylcholine receptor (anti-α3gAChR)...  相似文献   
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Neurological Sciences - Alzheimer’s disease (AD) diagnosis can be hindered by amyloid biomarkers discordances. We aim to interpret discordances between amyloid positron emission tomography...  相似文献   
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Neurological Sciences - Mini-Mental State Examination (MMSE) is one of the most used tests for the screening of global cognition in patients with neurological and medical disorders. Norms for the...  相似文献   
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