Gastrointestinal tract cancers: Genetics, heritability and germ line mutations.

Gastrointestinal (GI) tract cancers that arise due to genetic mutations affect a large number of individuals worldwide. Even though many of the GI tract cancers arise sporadically, few of these GI tract cancers harboring a hereditary predisposition are now recognized and well characterized. These include Cowden syndrome, MUTYH-associated polyposis, hereditary pancreatic cancer, Lynch syndrome, Peutz-Jeghers syndrome, familial adenomatous polyposis (FAP), attenuated FAP, serrated polyposis syndrome, and hereditary gastric cancer. Molecular characterization of the genes that are involved in these syndromes was useful in the development of genetic testing for diagnosis and also facilitated understanding of the genetic basis of GI cancers. Current knowledge on the genetics of GI cancers with emphasis on heritability and germ line mutations forms the basis of the present review.

Application of catheter and guidewire transmission technology in the reconstruction of gastroduodenal malignant stricture.

BACKGROUND: Gastroduodenal obstruction is a preterminal event in patients with advanced and recurrent malignancies of the stomach, pancreas, and duodenum. It severely limits the quality of life in affected patients due to constant vomiting and associated malnutrition. Gastroduodenal stent placement is a very safe and effective method in patients with unresectable malignant tumors. METHODS: Thirty-six patients with malignant gastroduodenal stenosis accompanied by gastrointestinal obstruction which was not traversable with a gastroscope were included in the study. Under X-ray monitoring, the catheter was inserted through the stenosis advancing with loach guidewire, which was later replaced by a stiff guidewire. A tri-lumen gastrojejunal catheter was then introduced using the stiff guidewire through the stenosis to perform gastrointestinal decompression and provide intestinal nutrition. In some patients, an intestinal stent was placed at the site of the stenosis. RESULTS: Intubation was successful in 35 patients out of 36. A total of 12 intestinal stents were successfully placed, including two at the pylorus, six at the site of gastrointestinal anastomosis, and four at the descending horizontal part of the duodenum. CONCLUSIONS: Establishing enteral nutrition via intubation using guidewire and catheter delivery technology is a simple, effective and safe strategy for patients with gastroscopic inaccessible malignant gastroduodenal stenosis, and it is recommended in hospital practice.

Laparoscopic Versus Open Adhesiolysis for Small Bowel Obstruction: A Single-Center Retrospective Case-Control Study.

AIM: This study is to investigate the short-term outcomes of small bowel obstruction (SBO) patients undergoing laparoscopic versus open adhesiolysis. PATIENTS AND METHODS: A total of 202 patients with SBO were enrolled in this study. The patients underwent either laparoscopic (n=101) or open adhesiolysis (n=101). The primary end point was 30-day overall complications and secondary outcomes included major complications such as superficial and deep wound infections, mortality, postoperative length of stay, and operative time. RESULTS: There was no statistically significant difference in the demographic parameters between laparoscopic and open adhesiolysis populations. The mean operative time for laparoscopic adhesiolysis was significantly less than open adhesiolysis (70±34.2 vs. 101±50.2, P=0.01). Statistically significant differences in flatus day (3.5±1.2 vs. 4.5±1.8, P=0.035) and postoperative hospital stay (6.4±2.1 vs. 7.2±2.9, P=0.041) were identified in favor of laparoscopic group, whereas the medical expenses for both groups were not different (31012.0±3412.9 vs. 30029.0±3100.9, P>0.05). The overall complications for open and laparoscopic group were 19.8% and 9.9%, respectively (P=0.048). The important factors that led to a significantly lower overall complications rate in laparoscopic group might result from the lower wound (9.9% vs. 2.0%, P=0.017) and infectious (10.9% vs. 3.0%, P=0.027) complications. CONCLUSIONS: The laparoscopic approach for SBO is feasible because of its fewer complications and hospital stay.

Highly Efficient Nondoped Organic Light Emitting Diodes Based on Thermally Activated Delayed Fluorescence Emitter with Quantum-Well Structure.

Highly efficiency nondoped thermally activated delayed fluorescence (TADF) organic light emitting diodes (OLEDs) with multiquantum wells structure were demonstrated. By using an emitting layer with seven quantum wells, the nondoped TADF OLEDs exhibit high efficiency with EQE of 22.6%, a current efficiency of 69 cd/A, and a power efficiency of 50 lm/W, which are higher than those of the conventional doped OLED and among the best of the TADF OLEDs. The high performance of the devices can be ascribed to effective confinement of the charges and excitons in the emission layer by the quantum well structure. The emission layer with multiquantum well structure is demonstrated to be cost effective for highly efficient nondoped TADF OLEDs and holds great potential for organic electronics.

Radiophotographically Controlled Nasointestinal Intubation to Treat Recurrent Postoperative Adhesive Ileus.

This study describes clinical experience and curative effect of radiophotographically controlled nasointestinal intubation in the treatment of small intestine arrangement in recurrent postoperative adhesive ileus. A 300-cm-long nasointestinal tube was installed into the jejunum through the nasal cavity under radiophotographic observation in 25 patients with recurrent postoperative adhesive ileus. The tube was advanced into the ileum by enterokinesia to relieve adhesive ileus and conduct small bowel arrangement. Duration of tube installation was 13 ± 11 min (range of 9-36 min). The success rate was 88 %. In 3 patients, assistance by a gastroscope was required. Twenty-one out of 25 patients were cured, making the cure rate of 84 %. The time for intestinal arrangement was 18.5 ± 3 days. The patients were followed up for 6 months to 2 years; there was 1 case of recurrence, while other patients recovered smoothly with no recurrence. A non-surgical nasointestinal intubation under radiophotography is a simple, safe, and effective management with few complications and beneficial outcome in recurrent postoperative adhesive ileus.

Highly Efficient Orange and Red Phosphorescent Organic Light-Emitting Diodes with Low Roll-Off of Efficiency using a Novel Thermally Activated Delayed Fluorescence Material as Host.

MTXSFCz with thermally activated delayed fluorescence is synthesized. Orange and red phosphorescent organic light-emitting diodes (PHOLEDs) with low efficiency roll-off exhibit external quantum efficiencies (EQE) up to 11.8% and 15.6%. The efficient upconversion from triplet to singlet of the host reduces the triplet density and thus affords a low efficiency roll-off of PHOLEDs.

Ocular albinism type 1-induced melanoma cell migration is mediated through the RAS/RAF/MEK/ERK signaling pathway.

Malignant melanoma has the highest risk of mortality among all types of skin cancer due to its highly metastatic potential. The ocular albinism type 1 (OA1) protein is a pigment cell­specific glycoprotein, which shares significant structural and functional features with G protein­coupled receptors. However, the role of OA1 in melanoma has yet to be elucidated. The present study aimed to investigate whether OA1 is involved in melanoma cell migration. OA1 was found to stimulate cell migration in a dose­dependent manner in cultured human melanoma cells. Furthermore, knockdown of OA1 using small interfering RNA was observed to significantly inhibit melanoma cell migration. In addition, the mechanism underlying OA1­induced melanoma cell migration was investigated. Stimulation of the RAS/RAF/mitogen activated protein kinase kinase (MEK)/extracellular signal­regulated kinase (ERK) pathway using growth factors enhanced OA1 expression and melanoma cell migration, whereas inhibition of this pathway using U0126 was observed to markedly decrease OA1 expression and the number of migrated cells. These findings indicate that OA1 is involved in melanoma cell migration and that OA1­induced melanoma cell migration is mediated through the RAS/RAF/MEK/ERK signaling pathway. Therefore, OA1 may serve as a novel therapeutic target for melanoma.

Isolation and structural characterization of a polysaccharide LRP4-A from Lycium ruthenicum Murr.

A complex polysaccharide, termed LRP4-A, was isolated from the fruit of Lycium ruthenicum Murr. and its structure was characterized. The crude polysaccharide LRP was obtained from the fruit of L. ruthenicum Murr. using hot water extraction followed by ethanol precipitation. The water-soluble polysaccharide LRP4-A was purified from LRP by anion-exchange chromatography and gel filtration chromatography. Its molecular weight was 1.05×10(5) Da. Monosaccharide composition analysis revealed that LRP4-A mainly consisted of rhamnose, arabinose, glucose, and galactose in the molar ratio of 1:7.6:0.5:8.6, with a trace of xylose. Structure of the polysaccharide LRP4-A was characterized using a series of analytical techniques, including methylation analysis, partial acid hydrolysis, IR, NMR, and ESI-MS. LRP4-A was identified to be a highly branching polysaccharide with a backbone of ß-(1→6)-linked galactose partially substituted at O-3 position. The branches were composed of (1→3)-linked-Gal, (1→3)-linked-Ara, (1→5)-linked-Ara, and (1→2,4)-linked-Rha. Arabinose, galactose, and glucose were located at the termini of the branches.

Isolation and structural characterization of the polysaccharide LRGP1 from Lycium ruthenicum.

A novel water-soluble glycoconjugate, designated as Lycium ruthenicum glycoconjugate polysaccharide 1 (LRGP1), was isolated from the fruits of Lycium ruthenicum Murr. The crude polysaccharide was obtained by hot water extraction and purified by ion-exchange and gelfiltration chromatography. Its molecular weight was 56.2 kDa determined by HPGPC (high performance gel permeation chromatography). Monosaccharide composition analysis revealed that it was composed of rhamnose, arabinose, xylose, mannose, glucose, and galactose in a molar ratio of 0.65:10.71:0.33:0.67:1:10.41. The existence of O-type carbohydrate-peptide linkage in LRGP1 was demonstrated by ß-elimination reaction. On the basis of monosaccharide composition, partial acid hydrolysis, methylation analysis and ESI-MS analysis, LRGP1 was characterized as a branched polysaccharide rich in arabinose and galactose with a backbone composed of (1→3)-linked Gal. The branches were composed of (1→5)-linked Ara, (1→2)-linked Ara, (1→6)-linked Gal, (1→3)-linked Gal, (1→4)-linked Gal and (1→2,4)-linked Rha. Arabinose, xylose, mannose, and glucose were located at the terminal of the branches.

Structural characterization of an arabinogalactan-protein from the fruits of Lycium ruthenicum.

A water-soluble arabinogalactan-protein (AGP), designated LRGP3, was isolated from the fruits of Lycium ruthenicum Murr. Its average molecular weight was 75.6 kDa. Monosaccharide composition analysis revealed that it was composed of rhamnose, arabinose, and galactose in a molar ratio of 1.0:14.9:10.4. Protein accounted for 1.7% of the AGP and was rich in hydroxyproline. On the basis of monosaccharide composition, partial acid hydrolysis, methylation analysis, ESI-MS, and NMR spectroscopy, LRGP3 was characterized as a highly branched polysaccharide with a backbone of (1→3)-linked ß-D-galactopyranosyl residues, many of which were substituted at the O-6 position by galactosyl or arabinosyl groups. The branches were composed of (1→5)-linked arabinose, (1→2)-linked arabinose, (1→6)-linked galactose, (1→3)-linked galactose, and (1→2,4)-linked rhamnose, and the major nonreducing termini were α-L-arabinofuranosyl residues.