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Silver nanowires (Ag NWs) have received considerable attention for flexible transparent conductive films (TCFs) since they provide a relatively low sheet resistance at a high transmittance. However, the diffuse light scattering, haze, has been regarded as a hurdle to achieve clarity of films. Here we revisit the Mie scattering theory to calculate the extinction and scattering coefficients of Ag NWs which were employed to estimate haze of TCFs. The theory predicted a decrease in haze with a decrease in Ag NW diameter which was supported by experimental investigations carried out using Ag NWs with 5 different diameters (17.6, 19.9, 22.5, 24.3, and 29.6 nm). Overall, excellent properties of TCFs (haze = 0.21%-1.8%, transmittance = 95.33%-98.45%, sheet resistance = 20.87-81.76 Ω sq -1 ) were obtained. Ag NWs with a diameter of 17.6 nm provided minimum haze values at equivalent sheet resistances (e.g., haze = 0.21%, transmittance = 98.45%, sheet resistance = 77.36 Ω sq -1 ) compared with ones with lager diameters and the controls in literatures. This work investigated the interdependence between haze and NW diameter and might provide a design guide for flexible Ag NW TCFs.

Background: Single-Site(®) port plus one conventional robotic port, a reduced-port robotic surgery (RPRS) for left-sided colorectal cancer, can enable lymphovascular dissection using the Endowrist(®) function; this allows safe rectal transection through an additional port and maintains the cosmetic advantage of single-incision laparoscopic surgery., Methods: Between August 2014 and December 2014, the study group included 11 patients who underwent a RPRS for left-sided colon cancer., Results: There was one (9.1%) case of descending colon cancer, six (54.5%) cases of sigmoid colon cancer, and four (36.4%) cases of rectosigmoid colon cancer. The mean total operation time and docking time were 289±77 and 17±7 min. The mean times to soft diet and possible length of stay were 5.6±0.8 and 7.4±0.7 days. The mean total number of lymph nodes harvested was 18.7±7.9. The mean proximal and distal resection margins were 7.8±4.7 and 4.7±2.4 cm., Conclusions: Reduced-port robotic surgery for left-sided colon cancer using the Single-Site(®) system appears to be feasible and safe using the new robotic single-access platform. Copyright © 2015 John Wiley & Sons, Ltd., (Copyright © 2015 John Wiley & Sons, Ltd.)

Purpose: In some patients more than 70 years of age with obstructive colorectal cancer, their concerns about the postoperative complications lead them to refuse surgery after the insertion of a stent. This study aimed to compare the postoperative outcomes between obstructive colorectal cancer patients aged less than 70 years and those aged 70 years and more who underwent surgery after the insertion of a colonoscopic stent., Methods: Patients with obstructive colorectal cancer who underwent surgery after the insertion of a colonoscopic stent between March 2004 and March 2014 were reviewed retrospectively by using medical records. The patients were divided into two groups: 22 patients were aged less than 70 years (group A) and 30 patients were aged more than 70 years (group B)., Results: Although no significant difference in comorbidity was noted between the two groups, the American Society of Anesthesiologists (ASA) score was higher in group B. There was no significant difference in cancer location, stage, or the time from the insertion of the stent to operation. The perioperative results including operation time, blood loss, and length of stay were not significantly different between the groups. The postoperative complications were also not significantly different., Conclusion: The surgical outcomes of elderly patients were similar to those of younger patients, despite higher ASA scores. These results indicate that surgery can be performed safely in elderly patients with obstructive colorectal cancer after the insertion of a stent.

Most ingested foreign bodies pass through the gastrointestinal tract without any incident. However, foreign bodies lodged in the appendix can cause an inflammatory reaction with or without perforation. Here, we present a case of a 54-year-old woman with perforated appendicitis who consumed wild game containing a shot pellet. Five months before admission, she had eaten the meat of a pheasant that had been shot with a shotgun. Abdominal computed tomography confirmed the diagnosis of perforated appendicitis with abscess due to a foreign body. Subsequently, a laparoscopic appendectomy was performed. Follow-up radiographs obtained after the surgery did not identify the foreign body. Histolopathologic examination confirmed appendiceal perforation with focal inflammation secondary to a foreign body.

Bowel perforation caused by a peritoneal dialysis (PD) catheter is an uncommon complication. It occurs mostly at the time of insertion of a catheter. Delayed perforation of the bowel by a PD catheter can also occur, but is even more uncommon. The ideal management of perforation of the colon by a PD catheter remains to be established because of its very low incidence. Definite surgery is the usual treatment. Here, we report on a 50-year-old male patient who presented with severe watery diarrhea owing to delayed rectal perforation caused by a PD catheter. A computed tomography scan revealed that the catheter tip was inside the lumen of the rectum. This was further confirmed by colonoscopy after bowel preparation. The PD catheter was removed via the original abdominal incision and the rectal perforation was closed using 3 endoscopic clips. The patient made an uneventful recovery.

Purpose: Clostridium difficile (C. difficile)-associated colitis, a known complication of colon and rectal surgery, can increase perioperative morbidity and mortality, leading to increased hospital stay and costs. Several contributing factors, including advanced age, mechanical bowel preparation, and antibiotics, have been implicated in this condition. The purpose of this study was to determine the clinical features of and factors responsible for C. difficile-associated colitis after colorectal cancer surgery., Methods: The medical records of patients who had undergone elective resection for colorectal cancer from January 2008 to April 2010 were reviewed. Cases that involved procedures such as transanal excision, stoma creation, or emergency operation were excluded from the analysis., Results: Resection with primary anastomosis was performed in 219 patients with colorectal cancer. The rate of postoperative C. difficile-associated colitis was 6.8% in the entire study population. Preoperative metallic stent insertion (P = 0.017) and aged sixty and older (≥ 60, P = 0.025) were identified as risk factors for postoperative C. difficile-associated colitis. There were no significant differences in variables such as preoperative oral non-absorbable antibiotics, site of operation, operation procedure, and duration of prophylactic antibiotics., Conclusion: Among the potential causative factors of postoperative C. difficile-associated colitis, preoperative metallic stent insertion and aged sixty and older were identified as risk factors on the basis of our data. Strategies to prevent C. difficile infection should be carried out in patients who have undergone preoperative insertion of a metallic stent and are aged sixty and older years.

The expression of melanoma antigen gene (MAGE), coding for tumor antigens recognized by cytotoxic T cell, is highly specific to cancer cells, but their use in the detection of a few cancer cells by reverse transcription-polymerase chain reaction (RT-PCR) has been limited by the low frequency of expression of individual MAGE genes. In order to increase MAGE detection rate in RT-PCR assay, here, we designed multiple MAGEs recognizing primers (MMRPs) that can bind to the sequences of cDNA of MAGE-1, -2, -3, -4a, -4b, -5a, -5b and-6 (MAGE 1-6) together. The nested RT-PCR assay using MMRPs, MAGE 1-6 assay, detected MAGE messages of 1 to 5 SNU484 cells in a background of 10(7) SNU638 cells. MAGE detection rate of MAGE 1-6 assay in cancers was higher than that of nested RT-PCR that detects single MAGE gene expression. The expressions of MAGE genes was detected by MAGE 1-6 assay in 70.4% (19/27) of head and neck cancer tissues, 91.7% (11/12) of breast cancer tissues, 75% (9/12) of lung cancer tissues. However, they were not detected in 18 benign lesions and 20 normal head and neck tissues and 30 blood samples from healthy donor. In conclusions, MAGE 1-6 assay can detect any cancer cells that express at least one of eight MAGE subtype genes, and this method may be very useful for the diagnosis of MAGE-expressing cancers.

CD44 is a cell adhesion molecule with numerous isoforms created by mRNA alternative splicing. Expression of CD44 variants has been suggested to play a potential role in tumor progression and metastasis. We designed primers CD44V, CD44V6/7, CD44R1 and CD44V6-10 to analyze and compare the roles of each CD44 variants. Expressions of CD44 variants were investigated in normal colonic mucosa, the lymph nodes which was histopathologically free of cancer cell, and cancer tissues of 44 human colorectal cancer patients by RT-PCR method. The expression of CD44V was observed in 28 out of 39 (71.8%) tumors and 7 out of 11 (63.6%) N1 normal regional lymph nodes, and CD44V6/7 was observed in 28 out of 39 (71.8%) tumors and 9 out of 11 (81.8%) N1 normal regional lymph nodes. The expressions of CD44V and CD44V6/7 were most frequently observed compared with any other CD44 variants. In normal colonic mucosa, the expression of CD44 variants are low but in cancer tissue and its regional lymph node, the expression of CD44V and CD44V6/7 were significantly higher and more frequent than any other CD44 variants (p<0.05). These results suggest that CD44V and CD44V6/7 can be a molecular marker for colorectal cancer and its micrometastasis to the regional normal lymph node.

Peutz-Jeghers syndrome is an autosomal dominant inherited disorder characterized by hamartomatous polyps in the small bowel and mucocutaneous pigmentation. Patients with Peutz-Jeghers syndrome often present as surgical emergencies with complications of the polyps, such as intussusception, bowel obstruction, and bleeding. Recently an increased risk of malignancies has also been reported. This study was initiated to determine the clinical features of Peutz-Jeghers syndrome in Korean patients, with special attention to the development of malignancies. Thirty patients with Peutz-Jeghers syndrome were investigated; their median age was 23.5 years, and symptoms appeared at a median age of 12.5 years. Family history was positive in one-half of cases, and mucocutaneous pigmentation was observed in almost all patients (93%). The jejunoileum was the most frequent site of the polyps, and there were generally 10-100 polyps. Multiple laparotomies were performed in a substantial portion of the patients, due mainly to polyp-induced bowel obstruction, and the surgical interventions were begun at a relatively young age (average 21.4 years). Four cases of small-bowel cancer and one case of breast cancer were detected in probands, at a relatively young age (mean 36 years). Cancers of the small bowel, stomach, colon, breast and cervix were diagnosed in the first relatives of the probands. Close follow-up from an early age should thus be performed in patients with Peutz-Jeghers syndrome as they are at high risk of surgical emergency and development of malignancy.

CD44 is a glycoprotein expressed in a wide variety of cell types. Recently expression of some alternatively-spliced variants of CD44 transcripts (CD44v) has been suggested to play a potential role in tumor metastasis and the detection of CD44v containing exon 6 to 11 may be helpful for the diagnosis of cancers. Expressions of CD44v containing exon 6 to 11 were investigated in 20 human colorectal cancer samples, peripheral blood leukocytes isolated from colorectal cancer patients, and 4 colorectal cancer cell lines using reverse transcription-polymerase chain reaction and Southern blot analysis. The standard form of CD44 transcripts was expressed in all samples tested. CD44v containing exon 6 to 11 was expressed in 18 cases of colorectal cancers (sensitivity = 90%), 3 out of 4 cell lines, and one normal tissue (specificity = 95%). These results suggest that the expression of CD44v containing exon 6 to 11 can be regarded as tumor specific and that this marker may be helpful for the early diagnosis of colon cancers, if specimens from the early stage are available.