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Gallstone disease, cholecysto- and choledocho-lithiasis, is one of the most common digestive diseases. Most patients with symptomatic cholecystolithiasis are recommended to undergo cholecystectomy to alleviate their symptoms like abdominal pain and jaundice. Approximately 10–20% of patients who undergo cholecystectomy for gallstones have choledocholithiasis. Nowadays, endoscopic and/or laparoscopic approaches are widely accepted as the treatment for patients with gallstone. Patients with cholecystolithiasis are usually treated by laparoscopic cholecystectomy, whereas patients with choledocholithiasis are done by endoscopic sphincterotomy (EST) or laparoscopic common bile duct exploration (LCBDE). Additionally, some cases are treated by biliary reconstruction such as biliary enteric anastomosis. In this chapter, currently available laparoscopic approaches as a minimally invasive surgery are introduced and discussed on the basis of pathogenesis of the gallstone.

Highlights • The article represents an extremely rare case of the combination of choledochocele and extra-hepatic bile duct duplication. • The combination of choledochocele and bile duct duplication might escalate the pancreatitis and cholangitis progression. • The pathogenesis in relation to pancreaticobiliary maljunction is discussed., Background Combination of choledochocele and extra-hepatic duct duplication is an extremely rare congenital abnormality. Case presentation The patient was an 81-year-old Japanese man. He visited the emergency room for severe abdominal colic pain. He was diagnosed with severe pancreatitis with cholelithiasis and treated conservatively by percutaneous trans-hepatic gallbladder drainage (PTGBD) for 4 months. Thereafter, he was transferred to our institute and cholangiography was performed via the PTGBD tube, revealing cholecysto- and choledocho-lithiasis. The cystic-duct joined the right hepatic duct with extra-hepatic bile duct duplication and the terminal bile duct flowed into the cystic papilla of Vater. The main pancreatic duct also joined into the cystic papilla. These observations confirmed choledochocele with extra-hepatic bile duct duplication. Surgical exploration was performed, and hepatico-jejunostomy with hepatic-ductplasty and cholecystectomy with choledocholithotomy were carried out. He was discharged and his course was uneventful. Conclusion A very rare combined case of choledochocele with bile duct duplication, which would escalate the pancreatitis and cholangitis, was successfully treated. Their pathogeneses in relation to pancreaticobiliary maljunction is discussed.

Background: Tumor vascular micro-environment has an important role in tumor progression and metastasis. The objective of this study was to assess the significance of metastatic hepatic tumor vascular micro-environment in relation to the response to the systemic 5-FU-based chemotherapy (FOLFOX or FOLFIRI).Methods: A total of 48 consecutive colorectal cancer (CRC) patients with hepatic metastasis were retrospectively reviewed, and factors, such as metastatic tumor vascular micro-environment, chemotherapy response, and hepatic resection, were analyzed. Tumor angiogenesis was microscopically evaluated by microvessel density (MVD) in sections stained immunochemically with CD34 in patients with hepatic resection. The angiogenesis in tumor micro-environment in association with ring enhancement (RE) on computed tomography (CT) was also examined.Results: Microscopic examination revealed that peripheral RE on CT of the metastatic tumor is associated with tumor angiogenesis by MVD. The overall response rate after 6 courses of first-line chemotherapy for the liver metastasis with RE on CT was 64% (23/36), whereas the response rate without RE was 25% (3/12), which was significantly different, although the survival rate of patients with RE-positive or without RE-negative tumors was not different.Conclusion: The peripheral RE on CT of the metastatic hepatic tumor was associated with the angiogenesis in tumor micro-environment and higher chemotherapy response.

The object of this paper is to clarify the feasibility and safety of robot-assisted laparoscopic cholecystectomy. Acute or chronic cholecystitis is the most common disease in patients, caused by cholecystolithiasis. Minimally invasive laparoscopic surgery is often performed for treatment of cholelithiasis. We performed robot-assisted laparoscopic cholecystectomy for the treatment of 5 patients with cholecystolithiasis. The patient underwent laparoscopic cholecystectomy using the ViKY Endo-Control System (ViKY, EndoControl, Grenoble, France). The robot-controlled laparoscopic holder was placed at the right axilla. The laparoscopic operation was performed via conventional 4-port access using the ViKY system with voice activation. All patients were treated successfully by this robot-assisted laparoscopic procedure, without any complications. Mean docking time using the ViKY was 16 minutes, mean resection time of the gallbladder was 62.2 minutes, operative time was 94.6 minutes, and the mean amount of the blood loss was minimal. Our initial experience demonstrated that robot-assisted laparoscopy was feasible and safe in patients with cholecystolithiasis, providing patient advantages. We also discuss the advantages and disadvantages of robot-assisted laparoscopic surgery.

Transparent glass fiber composites were prepared with a refractive-index-adjustable thermoplastic blend. The opacity of a polymer blend is affected by the phase separation and crystallization properties. Polyamide 6 (PA6)/poly (m-xylene adipamide) (MXD6) blends are intrinsically miscible and transparent in the molten state; further, crystallization is suppressed by polymer chain disordering induced by in-situ transamidation. Thus, the transparency of the molten state was maintained after a sufficient period of melt-mixing. The refractive index was adjusted to that of the glass fiber reinforcement by altering the PA6/MXD6 blend ratio. Injection-molded glass fiber composites of PA6/MXD6 had good transparency and mechanical properties.

Choledochoduodenostomy (CDD) was very useful alternatives for treatment for patients with common bile duct (CBD) stones, especially recurrent stones, giant stones with choledochal dilatation, and difficult or failed cases by endoscopic treatment. Furthermore, CDD was also applied to biliary bypass by malignant obstruction. In these days, minimal invasive laparoscopic approach is adapted in these disorders. We have conducted to perform a laparoscopic CDD for biliary alleviation for patients with endoscopic management of difficult CBD stone with choledochal dilatation. A side-to-side CDD was created intra-corporeally using water-tight running absorbable suture by handmade 4-0 monofilament with double side needles, starting from the right side of choledochus, and continued along posterior wall until the left side of the choledochus followed by anterior-wall anastomosis as the same manner. Five patients were treated successfully by this laparoscopic procedure and remained well without bile leakage and reflux cholangitis for the short-term follow-up. The median operative time and intracorporeally anastomosis time were 182 (167 - 209) min and 33 (30 - 38) min, respectively. Median blood loss was 32 (little-90) ml, median hospital stay was 7 (5 - 14) days, and median follow-up time was 18 months. Although this series was relatively small, this laparoscopic technique is feasible and safe for biliary alleviation, especially for endoscopic management of difficult or failed CBD stones, and would also potentially adapt to biliary bypass by malignant obstruction.

There is an increasing demand for highly thermally conductive and electrically insulating polymer materials for next-generation electronic devices, power systems, and communication equipment. Boron nitride nanosheets (BNNSs) are insulating materials with extremely high thermal conductivity. However, BNNSs suffer from the lack of facile and low-cost methods for producing large volumes of BNNSs, and extremely low through-plane thermal conductivities of BNNS/polymer composites as compared to the in-plane thermal conductivities. Herein, highly soluble, noncovalently functionalized boron nitride nanosheets (NF-BNNSs) with chlorosulfonic acid (CSA) were prepared by extremely facile and low-cost direct exfoliation of hexagonal boron nitrides (h-BNs), and acted as excellent nanofillers for dramatically improving both in- and through-plane thermal conductivities of insulating polymers. CSA is a cheap and versatile superacid with a large production volume. CSA showed strong physical adsorption on h-BN surfaces, giving few-layered NF-BNNSs in high yields (up to ∼25%). The crystallinity of the NF-BNNS was perfectly maintained even after CSA treatment. The physical adsorption of CSAs imparted high solubility for BNNSs in various organic solvents, yielding NF-BNNS uniformly dispersed-thermoplastic polymer composite films through a simple wet-process using predispersed NF-BNNS solutions. Random dispersion of NF-BNNSs in thermoplastic polymer films dramatically enhanced both the in- and through-plane thermal conductivities (10 W m

A series of copolycarbonates were prepared by transesterification polymerization of isosorbide, bisphenol A and diphenylcarbonate with several catalysts. When N,N-dimethylaminopyridine was used as a catalyst, the highest molecular weight copolymers were obtained. Based on the storage and tensile moduli, the polymers exhibited a higher strength than that of the bisphenol A-based polycarbonate. Based on these properties, these copolymers exhibit the potential for use as high-performance polymeric materials.

Surface modification of a layered polysilane consisting of two-dimensional crystalline silicon layers was investigated using n-alkylamines, α,ω-diaminoalkanes, and ω-aminocarboxylic acids. All products of the reactions with n-butyl- to n-hexadecylamines were dispersed as nanosheets in chloroform and exhibited the same blue light emission and photoluminescence spectra when exposed to UV light. After removal of the solvent, these products formed regularly stacked structures with an interlayer distance that increased in proportion to the alkyl length. The structure consists of bilayered alkyl chains with a tilt angle of ca. 47°. When the layered polysilane was reacted with α,ω-diaminoalkanes, the products were not dispersed in chloroform, because the silicon layers were covalently bonded by the diamines. The interlayer distances for these products also increased in proportion to the alkyl length. The layered polysilane was also successfully reacted with 12-aminododecanoic acid in pyridine or other polar solv...

[Background]The treatment of colorectal cancer (CRC) with metastasis is now widely accepted to be systemic chemotherapy of 5-FU base chemotherapy (FOLFOX or FOLFILI) in combination with molecular antibody. The objective of this study was to determine the significance of tumor angiogenesis in metastatic hepatic tumors in relation to the response of systemic chemotherapy. [Methods]A total of 48 consecutive CRC patients with hepatic metastasis who had been treated with or without hepatic resection were retrospectively reviewed, and factors, such as metastatic tumor angiogenesis and chemotherapy response, were analyzed. Tumor angiogenesis in association with ring-enhancement (RE) on computed tomography (CT) was also microscopically evaluated by microvessel counting (MVD) in sections stained immunochemically with CD34. [Results]The overall response rate after 6 courses of first-line chemotherapy for the liver metastasis with RE on CT was 64% (23/36), whereas the response rate without RE was 25% (3/12), which was significantly different. The survival rate of patients with or without liver resection of all RE-positive tumors was not different, but the survival rate of patients with liver resection was longer than that of patients without liver resection for all RE-negative tumors. Microscopic examination revealed that peripheral RE on CT of the metastatic tumor was associated with tumor angiogenesis by MVD. [Conclusions]The peripheral RE on CT of the metastatic hepatic tumor was associated with tumor angiogenesis and may predict chemotherapy response. A combination of liver resection with chemotherapy improves the survival of patients who have multiple hepatic metastasis. Citation Format: Hirotaka Okamoto, Shugo Shiba, Hiroshi Iino, Makoto Sudoh, Hiroyuki Wakana, Suguru Maruyama, Kenji Kawashima, Toshio Fukasawa, Daisuke Ichikawa, Hideki Fujii. Correlation of tumor angiogenesis with peripheral ring-enhancement on CT: Its predictive value of chemotherapy responses of colorectal metastatic hepatic tumor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1224.

e14505 Background: The treatment of colorectal cancer (CRC) with metastasis is now widely accepted to be systemic chemotherapy of 5-FU base chemotherapy (FOLFOX or FOLFILI) in combination with molecular antibody. The objective of this study was to determine the significance of tumor angiogenesis in metastatic hepatic tumors in relation to the response of systemic chemotherapy. Methods: A total of 48 consecutive CRC patients with hepatic metastasis who had been treated with or without hepatic resection were retrospectively reviewed, and factors, such as metastatic tumor angiogenesis and chemotherapy response, were analyzed. Tumor angiogenesis in association with ring-enhancement (RE) on computed tomography (CT) was also microscopically evaluated by microvessel counting (MVD) in sections stained immunochemically with CD34. Results: The overall response rate after 6 courses of first-line chemotherapy for the liver metastasis with RE on CT was 64% (23/36), whereas the response rate without RE was 25% (3/12), which was significantly different. The survival rate of patients with or without liver resection of all RE-positive tumors was not different, but the survival rate of patients with liver resection was longer than that of patients without liver resection for all RE-negative tumors. Microscopic examination revealed that peripheral RE on CT of the metastatic tumor was associated with tumor angiogenesis by MVD. Conclusions: The peripheral RE on CT of the metastatic hepatic tumor was associated with tumor angiogenesis and may predict chemotherapy response. A combination of liver resection with chemotherapy improves the survival of patients who have multiple hepatic metastasis.

We report a case of typical fibrolamellar hepatocellular carcinoma (FL-HCC) in a 16-year-old Japanese boy. This is very rare malignancy in Japan. The patient was referred for investigation of a large hepatic tumor and the results of tests for hepatitis B virus surface antigen and hepatitis C virus antibody were negative. Liver function test results and serum alpha-fetoprotein (AFP) levels were normal; however, the prothrombin induced by vitamin K absence/antagonist II was elevated. Computed tomography (CT) showed a large lobulated heterogeneously enhanced tumor in the posterior section of the liver. We diagnosed FL-HCC and performed posterior sectionectomy of the liver. The resected specimen contained a light brown and green tumor with a central fibrous scar, 10.0 cm in diameter. Microscopic and electron microscopic examinations revealed the typical features of FL-HCC. Immunohistochemically, the tumor cells were positive for cytokeratin (CK) 7, but negative for CK19 and AFP. The patient was alive without recurrence 48 months after surgery. Following this case report, we summarize the clinical features of the Japanese cases documented in the literature.

A single incisional laparoscopic surgery (SILS) approach is increasingly being used, taking advantage of the minimally invasive technique. The aim of this study was to evaluate the feasibility and the validation of SILS procedure for small bowel obstruction (SBO). Sixteen consecutive patients with SBO who underwent SILS release of ileus between April 2010 and March 2015 were compared with the conventional multiport laparoscopic treatment group of 16 patients matched for age, gender, and surgical procedure. Laparoscopic treatment was completed in a total of 14 patients in SILS group and 13 in multiport laparoscopic group. Two cases and 3 cases were converted to multiport laparoscopic surgery or open surgery. Eight patients with nonscar and nonadhesive ileus, such as internal hernia, obturator hernia, gallstone ileus, and intestinal invagination, were treated successfully in the laparoscopic procedure. There was no mortality in either of the groups. The mean procedural time was 105 minutes in the SILS group and 116 minutes in the multiport laparoscopic group. The mean amount of blood loss was not statistically different in either of groups (15 ml vs. 23 ml). Patients resumed oral intake after a mean of 2 days in the SILS and 3 days in the multiport groups with the statistically difference. The length of hospital stay was shorter in the SILS group (5 days vs. 7 days) with no statistically difference. Perioperative morbidity was seen in 2 patients in the SILS group and 3 patients in the multiport group. SILS approach has superior and/or similar perioperative outcomes to multiport approach for SBO. SILS release of ileus as an ultra-minimal invasion technique is feasible, effective, and offers benefits with cosmesis in simple adhesive or scar-less nonadhesive ileus patients.

Polycarbonates were synthesized by transesterification polymerization of isosorbide, bisphenol A, and diphenyl carbonate in the presence of n-BuSn(O)OH as the catalyst. The polymers were prepared by varying the ratio of the two monomers. The polymers exhibited good thermal stability, rigidity, and strength. The storage moduli for the polymers were 2.6 to 3.2 GPa at 25°C and increased with increasing isosorbide content. The dynamic mechanical analysis indicated that the storage moduli (E′) of the polymers are constant to higher temperatures than that of bisphenol A polycarbonate. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Alkyl-modified crystalline silicon nanosheets 2 were synthesized and maintained the crystal structure of a Si(111) plane, in which the dangling silicon bond is stabilized by capping with the alkyl group. 2 was characterized using UV-vis, Fourier transform-infrared, and X-ray photoelectron spectroscopies; X-ray diffraction; and X-ray absorption near edge structure analysis. A model structure is proposed that has a periodicity through the nanosheet surface.

A case of invasive ductal carcinoma of an ectopic pancreas in the stomach in a 74-year-old woman is presented. A 4.0 cm gastric submucosal tumor (SMT) was resected surgically. Histologically, the tumor showed cystic tissue consisting of an ectopic pancreas with foci of a moderately differentiated tubular adenocarcinoma. In this tumor, small pancreatic tissues, acini, Langerhans islets, and ductular cells were detected in the gastric SMT. The patient has experienced long-term survival. The incidence of pancreatic cancer of an ectopic pancreas is rare, and the etiology of this disease is discussed in the literature.

Introduction Laparoscopy for small bowel obstruction (SBO) has increasingly been performed for the advantages minimally invasive surgery provides. However, its benefit remains unclear. Methods From January 2004 to July 2011, we enrolled 28 consecutive patients who underwent a laparoscopic operation for SBO, secondary to postoperative adhesions. We compared the results of SBO patients treated laparoscopically with those of 25 patients who underwent conventional open laparotomy in a retrospective matched-pair analysis. Results Laparoscopic treatment was completed in 25 patients (89%), including 17 laparoscopic-assisted cases. The mean procedural time was 112 minutes in the laparoscopic group and 79 minutes in the open group (P

Hemosuccus pancreaticus is an unusual cause of gastrointestinal bleeding that occurs as a complication of chronic or acute pancreatitis. We report a case of extremely acute-onset hemosuccus pancreaticus occurring in a patient with chronic pancreatitis over a long-term follow-up after a Puestow procedure (side-to-side pancreaticojejunostomy). The patient was admitted to our hospital due to severe anemia and tarry stools indicative of gastrointestinal bleeding. Emergent endoscopy, including gastrointestinal fiberscopy and colon fiberscopy, showed no abnormal findings. Abdominal contrast-enhanced computed tomography and hemorrhagic scintigraphy did not detect a hemorrhagic lesion. Although interventional radiology was considered for diagnosis and treatment, conservative therapy seemed sufficient to affect hemostasis. Two weeks later, however, acute intestinal bleeding with hemodynamic shock occurred, and exploration was performed without delay. Intraoperative endoscopy through an incision of the reconstructed jejunal loop in the close proximal end revealed a site of active bleeding from the side-to-side anastomotic pancreatic duct. Following a longitudinal incision of the jejunal loop, a bleeding point was sutured and ligated on direct inspection. The patient showed a good postoperative course.

Silicon nanomaterials and nanostructures exhibit different properties from those of bulk silicon materials based on quantum confinement effects. They are expected to lead to the development of new applications of silicon, in addition to wide use in semiconductor devices. Aside from industrial interest, intriguing issues of academic interest still remain with respect to the origins of their characteristic properties. Zero- and one-dimensional crystalline silicon nanomaterials have been synthesized, to date, by using many methods and there has been rapid progress in size control and modification procedures. However, there have been only a few examples of silicon nanomaterials with atomic-order thickness akin to carbon nanomaterials, such as two-dimensional silicon nanosheets. Moreover, mass production of silicon nanomaterials with relatively low cost is not easily achievable, due to the typically severe conditions required for fabrication, such as high temperature and ultralow pressure. Recently, we have developed a soft synthetic method for silicon nanosheets with chemical surface modification in a solution process. This review provides methods for the synthesis and modification of silicon nanosheets and other silicon nanomaterials with examples of their potential applications.

A nylon 6-clay hybrid (nanocomposite, NCH) was developed by Toyota CRDL group. In the NCH, the silicate layers of clay mineral are dispersed on a nanometer level and are strongly interacted with the matrix, and then significant improvements in the mechanical properties of the material or the discovery of unexpected new properties were realized. Polypropylene (PP) is the most widely used polymer, and then an appearance of a PP–clay nanocomposite has been desired for a long time. As a PP does not include any polar groups in its backbone, it was thought that the homogeneous dispersion of the silicate layers would not be realized. But we have developed successfully PP–clay nanocomposite using organoclay and modified PP. That is, organophilic clay, PP oligomer carrying polar groups and PP were melt-blended. This is a direct polymer intercalation process for preparing polymer nanocomposites by melt compounding, a useful process from an industrial standpoint. We have also developed successfully other polyolefin polymers (polyethylene), polyolefin rubbers (ethylene–propylene elastomer, ethylene–propylene diene monomer) and nanocomposites by this direct polymer intercalation process or by techniques based on direct polymer intercalation process. These prepared polyolefin nanocomposites exhibit superior mechanical, thermal and gas barrier properties. Polyolefins (polypropylene (PP), polyethylene and so on) and polyolefin rubbers (ethylene propylene diene monomer, ethylene propylene elastomer and so on) are the most widely used polymers. Therefore, a development of a polyolefin and polyolefin rubber–clay nanocomposite has been desired for a long time. As these polyolefin polymers do not include any polar groups in its backbone, it was thought that the homogeneous dispersion of the silicate layers would not be realized. But we have successfully developed these polymer–clay nanocomposites by using various methods.

Layered polysilane (Si 6 H 6 ) has a graphite-like structure with higher capacity than crystalline silicon. The rate of increase of the thickness of a layered polysilane electrode after 10 charge–discharge cycles was smaller than that for a Si powder electrode, although the layered polysilane electrode has higher capacity. The structural changes of electrochemically lithiated and delithiated layered polysilane at room temperature were studied using scanning electron microscopy, X-ray diffraction and Raman spectroscopy. Layered polysilane became amorphous by insertion of lithium to 0 V, whereas insertion of lithium into crystalline silicon produces Li 15 Si 4. Layered polysilane maintained an amorphous state during lithium insertion and deinsertion, whereas silicon changed between Li 15 Si 4 and amorphous Li x Si, which explains the smaller volume change of a layered polysilane electrode compared with a Si powder electrode.

The present study reports a case involving a 17-year-old man who was brought to the emergency department of our hospital with severe upper abdominal pain following a blow received in a rugby game. Emergency computed tomography (CT) revealed severe pancreatic neck injury, and the patient was subsequently given conservative treatment in the High Care Unit. Forty-eight hours later, follow-up enhanced CT revealed that the pancreas was clearly lacerated and the amount of peripancreatic fluid was increasing; furthermore, serum amylase and elastase levels were elevated. Endoscopic retrograde pancreatography revealed that contrast medium in the main pancreatic duct (MPD) had leaked to the parenchyma, indicating an MPD injury. To prevent traumatic pancreatitis from worsening, a stent was inserted endoscopically to a site distal to the injured portion of the MPD. Thereafter, the patient's condition dramatically improved, and his serum amylase levels returned to normal. CT revealed that the apparent pancreatic edema and peripheral fluid were also decreased. During a short-term follow-up period of 6 months, removal of the stent was uneventfully carried out and the patient did not develop any exocrine or endocrine insufficiency. We suggest that, in some cases, endoscopic management of traumatic pancreatic duct disruption is feasible and effective.

Two- and three-component polyurethanes containing 1,4:3,6-dianhydro-D-sorbitol (isosorbide) derived from glucose were synthesized using n-BuSn(=O)OH·H 2 O as a catalyst, and the thermal properties (T g , T d ) of the polymers were investigated by differential scanning calorimetry and thermogravimetric analysis. We carried out molds for polyurethanes, the molds of polyurethanes were obtained. The dynamic mechanical analyzes showed that the storage modulus values of the three-component polymers were constant to a higher temperature than those of the two-component polymers. The storage moduli (E'), loss moduli (E"), and values of tan δ for the polymers were obtained. The rigidity of three-component polymers was increased by the introduction of bisphenol A and diphenylmethane group to two-component polymer.

Effects of the addition of PDLA on the crystallization behavior of PLLA was investigated by means of differential scanning calorimetry, wide-angle X-ray diffraction, melt rheology, and polarized optical microscopy. Nonisothermal and isothermal crystallization behavior of PLLA including low (l-PDLA) and high molecular weight PDLA (h-PDLA) were studied. PLLA/PDLA asymmetric blends form stereocomplex (SC) crystal and stay unmelted at 200 °C in the PLLA melt. Nonisothermal crystallization measurement from 200 °C showed monotonous rise in the crystallization temperature for PLLA/h-PDLA blend, while peculiar concentration dependence was observed for PLLA/l-PDLA blends. The acceleration effect was more pronounced in PLLA/h-PDLA, although the crystallinity of SC was lower than PLLA/l-PDLA blends, which implies the importance of higher order structure of SC for the crystallization of PLLA. From isothermal crystallization kinetics measurements, the acceleration effect in PLLA/h- and l-PDLA blends was found to enhan...

Effects of the crystallization temperature on the crystal structure and its melting behavior of poly (l-lactic acid) (PLLA) have been investigated by means of wide-angle (WAXS) and small-angle (SAXS) X-ray scattering, optical microscopy, and differential scanning calorimetory (DSC). PLLA was found to crystallize as the α form when the crystallization temperature Tc was higher than 120 °C, while significant change in lattice parameters was seen for Tc's below 120 °C. The ratio of the a- and b-axis lengths begins to decrease with Tc below 120 °C and is 31/2 below 90 °C, which suggests a new crystalline form with hexagonal packing, namely, the α‘ form. The possible reason for α‘ formation is discussed. High-temperature WAXS and SAXS measurements showed that α‘ crystal transforms into ordered a form during heating. The transition takes place at 150 °C without a decrease in scattering intensity and without heating rate dependence. The mechanism for the transition is discussed.

Boron nitride nanosheets (BNNSs) with micron-sized edges were prepared in high yields by direct exfoliation of bulk hexagonal boron nitrides using ionic liquids (ILs). The ILs strongly attached onto BNNS surfaces, and dramatically enhanced the exfoliation, giving highly concentrated BNNS dispersions (∼1.9 mg mL(-1)) and yields reaching ∼50%.

Polylactide (PLA)/N,N-ethylenebis(12-hydroxystearamide) mixture was prepared by using melt extrusion. The detailed crystallization kinetics and morphology of neat PLA and a mixture were studied by using polarized optical microscopy, light scattering, differential scanning calorimetry, and wide-angle X-ray diffraction analyses. The overall crystallization rate and spherulitic texture of PLA were strongly influenced in presence of the organic additive. The overall crystallization rate of matrix PLA increased with addition of WX1. These behaviors indicated that WX1 crystallites, which crystallized at the very early stage of PLA crystallization act as a nucleating agent for PLA crystallization.

Ethylene propylene rubber–clay nanocomposites (EPR–CNs) were prepared by melt-compounding maleic anhydride modified EPR (EPR-MA) with organophilic clay, and their properties were examined. Silicate layers of organophilic clay were found to exfoliate and homogeneously disperse into the nanometer level in the nanocomposites by transmission electron microscopy observation. EPR–CNs exhibited higher tensile moduli compared to EPR-MA and composites containing conventional fillers such as carbon black, talc. The storage moduli of EPR–CNs were also higher than those of EPR-MA and the conventional composites. Creep resistances of EPR–CNs were much improved compared for EPR-MA. Degree of swelling in hexadecane was remarkably restricted. Improvement of these properties is caused because dispersed silicate layers have much large interface with the EPR matrix and are thought to strongly restrain the EPR polymer chains. Nanocomposite technology using small amount of silicate layers is useful to improve properties of thermoplastic elastomer. Various kinds of thermoplastic elastomers are expected to be produced by loading of silicate layers with or without conventional fillers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 758–764, 2004

Small-cell carcinoma of the gallbladder is a very rare tumor. In this report, we describe a patient with small-cell carcinoma combined with adenocarcinoma in the gallbladder. The patient was a 70-year-old man, who clinically manifested systemic lymphadenopathy. An incisional biopsy of Virchow's lymph node revealed small-cell carcinoma. Abdominal computed tomography (CT) showed massive multiple paraaortic lymph node swelling and a round mass in the gallbladder, although chest CT did not show any abnormal masses in the lung. After two courses of chemotherapy (PVP therapy; cisplatin [CDDP], 80 mg/m(2), day 1, intravenous injection; and etoposide [VP-16], 50 mg/m(2), every day, per oral intake; given every 3 weeks) were performed, the systemic lymphadenopathy had completely diminished and only the gallbladder tumor remained on clinical examinations. Endoscopic retrograde cholangiopancreatography (ERCP) revealed nodular tumors in the gallbladder fundus. Cholecystectomy with partial resection of the liver was performed. Pathological examination revealed small-cell carcinoma combined with adenocarcinoma of the gallbladder. We discuss the characteristics and the treatment of this rare tumor.

Polyethylene-clay hybrids have been prepared successfully by melt compounding with maleic anhydride grafted polyethylene (MA-g-PE), organophilic clay and polyethylene. In these polyethylene-clay hybrids, the silicate layers of the clay were exfoliated and dispersed to the monolayers. The hybrids exhibit higher tensile yield strengths and tensile moduli than those of polyethylene matrices and those of polyethylene-inorganic clay composites. When the 5-wt% clays were loaded, the tensile yield strength and the tensile modulus of the hybrid were, respectively, 1.4 and 1.8 times higher than those of the polyethylene/MA-g-PE mixture. The gas permeability of that clay hybrid decreased 30% compared with polyethylene/MA-g-PE mixture.

We report a novel compounding process using Na–montmorillonite water slurry for preparing novel nylon 6/Na–montmorillonite nanocomposites. In this compounding process, the Na–montmorillonite slurry was blended with melting nylon 6 using an extruder, followed by removing the water. The Na–montmorillonite silicate layers were found to be exfoliated and dispersed homogeneously at nanometer level in the nanocomposites with an electron transmission microscope. The exfoliated Na–montmorillonite silicate layers were fixed in the nylon 6 matrix almost as they were in water. The nylon 6/Na–montmorillonite nanocomposites, loaded with only 1.6 wt% clay silicate layers, exhibited high strength, high modulus, high heat distortion temperature and low gas permeability compared to neat nylon 6. The properties of the nylon 6/Na–montmorillonite nanocomposites were nearly equal to those of conventional nylon 6/clay nanocomposites prepared by dry-compounding nylon 6 and organophilic clay ion-exchanged with alkylammonium ions.

Single-incisional laparoscopic surgery (SILS) has emerged as an attempt to further enhance the cosmetic benefits and reduce the morbidity of minimally invasive surgery. We present an approach of SILS adhesiolysis to adhesive strangulated ileus. A 70-year-old female patient, who had undergone laparoscopic low anterior resection 6 years before, underwent SILS adhesiolysis to a midline surgical incision wound adhesion site. The surgery was performed with only a 2.5-cm left-side transrectus incision using the SILS port. Laparoscopy revealed intestinal torsion and congestion with adhesion of the ileum to the previous surgical incision wound. SILS adhesiolysis was successfully carried out. The patient was discharged 4 days after surgery. SILS adhesiolysis is a feasible and efficient procedure in certain cases.

Polypropylene (PP)/clay nanocomposites (PPCNs) were autoclave-foamed in a batch process. Foaming was performed using supercritical CO 2 at 10 MPa, within the temperature range from 130.6°C to 143.4°C, i.e., below the melting temperature of either PPCNs or maleic anhydride-modified PP (PP-MA) matrix without clay. The foamed PP-MA and PPCN2 (prepared at 130.6°C and containing 2 wt% clay) show closed cell structures with pentagonal and/or hexagonal faces, while foams of PPCN4 and PPCN7.5 (prepared at 143.4°C, 4 and 7.5 wt% clay) had spherical cells. Scanning electron microscopy confirmed that foamed PPCNs had high cell density of 10 7 -10 8 cells/mL, cell sizes in the range of 30-120 μm, cell wall thicknesses of 5-15 μm, and low densities of 0.05-0.3 g/mL. Interestingly, transmission electron microscopic observations of the PPCNs' cell structure showed biaxial flow-induced alignment of clay particles along the cell boundary. In this paper, the correlation between foam structure and rheological properties of the PPCNs is also discussed.

Material recycling technology for automotive tire rubber waste was developed by the continuous devulcanization method. The deodorization during the recycling process has become possible by the newly developed method. The devulcanized rubber obtained by these methods from tire rubber waste, generated from both the manufacturing products and scrap tires, shows excellent mechanical properties applicable to the new tire rubber compounds in engineering practice. Furthermore, it was confirmed by actual road tests that a test truck tire containing 10 wt % of the devulcanized rubber in the tread might exhibit tread wear behavior almost equal to that for the standard type with the new rubber compound.