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31.

Background

N-Acetylglucosaminyltransferase V (GnT-V), an enzyme that catalyzes the β1-6 branching of N-acetylglucosamine on asparagine-linked oligosaccharides of cellular proteins, enhances the malignant behaviors of carcinoma cells in experimental models. The aim of this study was to determine clinical significance of GnT-V expression in human pT2 gallbladder carcinoma with simple in vitro experiments.

Methods

Ninety patients with pT2 gallbladder carcinoma were included for this study. The in vitro and in vivo biological effects of GnT-V were investigated using gallbladder carcinoma cells with variable GnT-V expression levels induced by a small interfering RNA.

Results

Of the 90 cases, 57 showed positive staining and the remaining 33 demonstrated negative staining, the subcellular localization in the 57 cases was classified into the granular-type in 31 cases and the diffuse-type in 26 cases. In 76 cases with curative resection, postsurgical survival was significantly poorer in those showing positive staining than in those showing negative staining (P = 0.028). In all of the 76 cases, postsurgical recurrence was significantly more frequent in those showing diffuse-type localization than in those showing negative staining. Experimental analyses demonstrated that the down-regulation of GnT-V expression in gallbladder carcinoma cells induced suppression of cell growth in vitro. The expression levels of GnT-V in the cells were highly correlated with the rapid in vivo growth coupled with the enhanced angiogenesis, and the tendency to form liver metastasis.

Conclusions

GnT-V expression in the subserosal layer of pT2 gallbladder carcinoma is correlated with the aggressiveness of the disease.  相似文献   
32.

Background

Although several population-based studies have shown higher hospital volume (HV) to be associated with better outcomes in acute pancreatitis, they failed to adjust for disease severity and did not take into account the potentially non-linear relationship between HV and outcomes. Using a Japanese nationwide administrative database, this study aimed to evaluate the volume–outcome relationship in acute pancreatitis by means of statistical methods that permitted such considerations.

Methods

In-hospital mortality, length of stay, and total costs for patients with acute pancreatitis were analyzed using multivariate regression models fitted with generalized estimating equations. Adjustment for severity was based on the Japanese Severity Scoring System and other patient characteristics. We used restricted cubic spline functions to examine the potential non-linear relationships between HV and outcomes.

Results

In all, 17,415 eligible patients with acute pancreatitis were identified from 1,032 hospitals between 1 July 2010 and 30 September 2011. The in-hospital mortality rate was 2.6 %, and the median total costs were US $7,740 (interquartile range, 5,150–11,920). The overall and non-linear volume–outcome relationships were not significant either for in-hospital mortality or total costs. The median length of stay was 14 days (interquartile range, 10–22), and high HV was positively associated with shorter hospitalization (overall, P < 0.001; non-linear, P = 0.194).

Conclusions

Despite the shorter hospitalization with higher HV, no inverse volume–outcome relationship was evident for acute pancreatitis. Further evidence is required to justify the volume-based selective referral of acute pancreatitis patients.  相似文献   
33.
34.
An optical sensor with the ability to detect and determine water over a wide concentration range is highly desirable in the laboratory and industry. Here the sensitivity and spectral responses of an intramolecular charge transfer-type colorimetric and fluorescence sensor with β-carboline structure are tuned and improved significantly over various water contents in the organic solvent by fusion with an electron-donating juloidine structure and complexation with boron trifluoride (BF3). The sensors, ET-1 and ET-1-BF3, developed in this study can respond differently depending on water content. ET-1-BF3 releases BF3 to generate ET-1 by addition of a trace amount of water, and ET-1 forms hydrogen bonds with one water molecule in low water contents and a hydrogen-bonded proton transfer complex with several water molecules in high water contents, accompanying gradual color and fluorescence changes. This work shows a promising approach to the sensitive detection and precise determination of water over the whole concentration range using a simple and practical method with optical sensors.

An intramolecular charge transfer-type optical sensor fused with a juloidine structure and complexed with boron trifluoride can detect and determine water over a wide concentration range.  相似文献   
35.
Cholangiocarcinoma (CC) of the biliary tract occasionally presents a predominant intraductal papillary growth in the bile ducts, called as biliary tract carcinoma (BTC) of papillary growth (PG) and intrahepatic CC (ICC) of intraductal growth (IG) type. Recently, intraductal papillary neoplasm of bile duct (IPNB) has been proposed as a pre-invasive biliary neoplasm. This study was performed to characterize pathologically BTC of PG type and ICC of IG type with respect to IPNB. It was found that 126 of such 154 CCs (81.8%) fulfilled the criteria of IPNB, while the remaining 28 cases showed different histologies, such as tubular adenocarcinoma and carcinosarcoma. These IPNBs occurred in old aged patients with a male predominance, and the left lobe was rather frequently affected in the liver. A majority of these cases were high grade IPNB (43 cases) and invasive IPNB (77 cases), while low grade IPNB was rare (6 cases). Pancreatobiliary type was predominant (48 cases) followed by gastric (30 cases), intestinal (29 cases) and oncocytic (19 cases) types. Mucus hypersecretion was found in 45 cases, and this was frequent in IPNB at the intrahepatic large bile duct and hilar bile ducts but rare at the extrahepatic bile ducts. Interestingly, 36 cases of high grade and invasive IPNBs contained foci of moderately differentiated adenocacinoma within the intraductal papillary tumor. In conclusion, a majority of ICC of IG type and BTC of PG type could be regarded as a IPNB lineage, and clinically detectable IPNBs were already a malignant papillary lesion.  相似文献   
36.
In the management of patients with craniosynostosis, it is important to understand growth curve of the normal cranium. Although three-dimensional (3D) computed tomography (CT) images taken in thin slices are easily available nowadays, data on the growth curves of intracranial volume (ICV), cranial length, cranial width, and cranial height in the normal cranium are mainly based on older studies using radiography, and there are insufficient reports using CT images especially taken in thin slices. The purpose of this study was to establish growth curves in the normal cranium of Japanese children using thin-slice images. Cranial images of 106 subjects (57 males, 49 females; aged 0–83 months) without significant cranial abnormalities were retrospectively analyzed. Using thin-slice CT images, the ICV and two-dimensional parameters such as cranial length, cranial width, and cranial height were measured by iPlan, followed by generating growth curves and calculating cephalic index (CI). ICV calculated from thin-slice CT images was compared with that obtained by substituting two-dimensional parameters into Mackinnon formula. The ICV growth curves for males and females were similar in shape. As with the ICV, the two-dimensional parameters increased most rapidly in the first year after birth. There was no significant difference in CI between the sexes or among any age groups. ICV calculated from thin-slice 3D CT images was 60% of that obtained from Mackinnon formula. These data will enable us to compare these specific measurements in craniosynostosis patients directly with those of normal children, which will hopefully help in managing these patients.  相似文献   
37.
38.
Couinaud described three fundamental approaches at the hepatic hilus in liver surgery. The Glissonean pedicle approach at the hepatic hilus is one of these procedures and provides anatomical hepatectomy for hepatocellular carcinoma (HCC). The Glissonean pedicle approach was introduced by Couinaud and Takasaki in the early 1980s. The key of the Glissonean pedicle approach is clamping the pedicle first, secondly confirming the territory, which includes the HCC, and finally dissecting the liver parenchyma. This procedure prevents intrahepatic metastasis of HCC, which spreads along the portal vein and improves the overall survival after surgery. Another key feature is that we do not have to consider any variations of the vascular elements in the hepatoduodenal ligament under the hilar plate. This procedure allows an approach to the tertiary branches, which feed a smaller anatomical area than Couinaud's segment. We refer to this area as a cone unit of the liver. The procedure is also available in laparoscopic hepatectomy and provides new knowledge of the surgical anatomy, especially for small anatomical liver resection in the cirrhotic liver.  相似文献   
39.
Endoscopic placement of a self‐expandable metal stent (SEMS) has become a mainstream treatment to relieve non‐resectable distal malignant biliary obstructions—its longer patency and cost‐effectiveness were demonstrated in comparison with plastic biliary stents in several randomized controlled trials. Despite advances in ERCP devices and SEMSs themselves to enable safe and effective biliary drainage via a SEMS, several significant aspects of the endoscopic placement of SEMS must be considered; otherwise, SEMS‐related complications and early SEMS dysfunction may occur. Also, SEMS dysfunction, including occlusion and migration, occurs at a certain frequency in the long term, and appropriate reintervention is necessary to preserve the quality of life of the patient. Here, we present tips for endoscopic transpapillary SEMS placement for distal malignant biliary obstruction and reintervention for SEMS dysfunction.  相似文献   
40.

Background

Reconstruction of the extensor mechanism after resection of the proximal tibia is challenging, and several surgical procedures are available. The purpose of this study was to determine the outcome of the fibular transposition technique for reconstruction of the extensor mechanism of the knee after proximal tibial resection.

Methods

We retrospectively reviewed five consecutive patients who underwent resection of the proximal tibia with prosthetic reconstruction and reconstruction of the extensor using fibular transposition between 1997 and 2011. There were two female and three male patients with a mean age of 50 years (range, 27 to 76 years). A follow-up evaluation included both passive and active range of motion, extensor lag, the MSTS score and complications.

Results

Patients were followed up for 93 months (range, 44 to 160 months). The mean extensor lag and active flexion were four degrees (range, 0 to 10°) and 103° (range, 85 to 110°), respectively. The mean MSTS score was 80% (range, 73 to 90%). All patients were able to ambulate without crutches at the latest follow-up.

Conclusions

The utilization of the fibular transposition technique is a simple, reliable, and successful procedure for extensor reconstruction after proximal tibial resection.  相似文献   
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