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The selenides of platinum-group metals (PGMs) are emerging as promising catalysts for diverse electrochemical reactions. To date, most studies have focused on single metal or bimetallic systems, whereas the preparation of a high-entropy (HE) selenide consisting of five or more PGM elements holds the promise to further enhance catalytic performance by introducing abundant active sites with various local coordination environments and electronic structures. Herein, we report for the first time the synthesis of PGM-based HE-Selenide (HE-Se) nanoparticles with a unique amorphous structure. The atomic metal-Se coordination and the presence of short-range order were thoroughly revealed. It is further shown that the amorphous HE-Se can be facilely transformed into a single-phase crystalline HE-Se with a cubic structure by thermal annealing. Catalytically, the amorphous HE-Se showed better acidic hydrogen evolution activity over monometallic PGM-based selenides and the crystalline counterpart, demonstrating the advantages of high-entropy configuration and amorphous structure. Our findings may pave the way toward the synthesis and property exploration of amorphous PGM-based selenides with tunable compositions., (© 2024 Wiley-VCH GmbH.)

A urachal remnant is a disorder resulting from a disturbance in the closure process of the urachus. A 55-year-old man was referred to our hospital for treatment of gallstones. The computed tomography scan revealed a cystic mass in the lower abdomen connecting to the urinary bladder. The preoperative diagnosis was a urachal cyst. Simultaneous laparoscopic cholecystectomy, mass resection, and urachectomy were performed. The mass on the cranial side of the urinary bladder was located on the median umbilical ligament. Both were resected and removed, along with the umbilicus. The postoperative course was uneventful. The histopathological diagnosis was urachal mucinous cystadenoma. There is no sign of a recurrence. A complete resection without damage is especially important for mucinous tumors of the urachal remnant because the injury to the tumor may lead to the development of pseudomyxoma peritonei. Only seven cases of mucinous cystadenoma of the urachal remnant were reported in English literature, and only one of these was treated with laparoscopic surgery. In our case, complete resection was possible by taking advantage of the magnifying effect of laparoscopic surgery. Furthermore, we are able to provide very clear intraoperative images and specimen photographs, which we believe will be useful for readers. Laparoscopic surgery will be beneficial when treating similar cases in the future. However, it should be kept in mind that a safe resection requires careful and meticulous technique., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Mizuta et al.)

The demand for powder X-ray diffraction analysis continues to increase in a variety of scientific fields, as the excellent beam quality of high-brightness synchrotron light sources enables the acquisition of high-quality measurement data with high intensity and angular resolution. Synchrotron powder diffraction has enabled the rapid measurement of many samples and various in situ/operando experiments in nonambient sample environments. To meet the demands for even higher throughput measurements using high-energy X-rays at SPring-8, a high-throughput and high-resolution powder diffraction system has been developed. This system is combined with six sets of two-dimensional (2D) CdTe detectors for high-energy X-rays, and various automation systems, including a system for automatic switching among large sample environmental equipment, have been developed in the third experimental hutch of the insertion device beamline BL13XU at SPring-8. In this diffractometer system, high-brilliance and high-energy X-rays ranging from 16 to 72 keV are available. The powder diffraction data measured under ambient and various nonambient conditions can be analysed using Rietveld refinement and the pair distribution function. Using the 2D CdTe detectors with variable sample-to-detector distance, three types of scan modes have been established: standard, single-step and high-resolution. A major feature is the ability to measure a whole powder pattern with millisecond resolution. Equally important, this system can measure powder diffraction data with high Q exceeding 30 Å -1 within several tens of seconds. This capability is expected to contribute significantly to new research avenues using machine learning and artificial intelligence by utilizing the large amount of data obtained from high-throughput measurements., (open access.)

A 50-year-old male was referred to our hospital for the further evaluation and treatment of abdominal pain. He was diagnosed with complicated appendicitis using computed tomography. After conservative treatment, he underwent an interval appendectomy. A histopathological examination revealed a goblet cell carcinoid(GCC)of the appendix with subserosal invasion. He underwent laparoscopic ileocecal resection with D3 lymph node dissection. Histopathological findings showed neither residual tumor nor lymph node metastasis. The patients is currently followed as an outpatient without recurrence. Here we report our experience with GCC, a rare disease.

A 56-year-old woman. She was underwent a lower gastrointestinal endoscopy for bloody stool, and type 2 advanced rectal cancer was found. In CT scan, although distant metastasis is not found, the tumor has been expanded to the dorsal side. So, infiltration into the sacrum was suspected. For the risk of bleeding and residual tumor in circumferential resection surface, it was decided to perform pre-operative adjuvant chemotherapy. Because RAS gene has no mutation, the regimen chose CAPOX plus cetuximab. Although skin damage and cytopenia were observed, there was no appearance of adverse events that were intolerant, and 4 courses were performed. Although scar stenosis was observed in the endoscope after 4 courses, tumor size decreased. Even in CT, the wall thickening was significantly reduced, and progress to the tumor dorsal side was also reduced, so laparoscopic lower anterior resection was performed. During surgery, the tumor dorsal side sacral infiltration was suspected, although observed a sclerotic change, it is relatively easily peelable, it was possible to safely complete the laparoscopic operation. Even after the operation, the course was good, and it was discharged from the hospital lightly on the 12th day after the operation. In pathological diagnosis, medium-differentiated adenocarcinoma, T3, N0, histological therapeutic effect of chemotherapy was grade 2. Cetuximab combination regimen was considered to be an effective option.

Porous sorbents are materials that are used for various applications, including storage and separation. Typically, the uptake of a single gas by a sorbent decreases with temperature, but the relative affinity for two similar gases does not change. However, in this study, we report a rare example of "crossover sorption," in which the uptake capacity and apparent affinity for two similar gases reverse at different temperatures. We synthesized two soft porous coordination polymers (PCPs), [Zn 2 (L1)(L2) 2 ] n (PCP-1) and [Zn 2 (L1)(L3) 2 ] n (PCP-2) (L1= 1,4-bis(4-pyridyl)benzene, L2=5-methyl-1,3-di(4-carboxyphenyl)benzene, and L3=5-methoxy-1,3-di(4-carboxyphenyl)benzene). These PCPs exhibits structural changes upon gas sorption and show the crossover sorption for both C 2 H 2 /CO 2 and C 2 H 6 /C 2 H 4 , in which the apparent affinity reverse with temperature. We used in situ gas-loading single-crystal X-ray diffraction (SCXRD) analysis to reveal the guest inclusion structures of PCP-1 for C 2 H 2 , CO 2 , C 2 H 6 , and C 2 H 4 gases at various temperatures. Interestingly, we observed three-step single-crystal to single-crystal (sc-sc) transformations with the different loading phases under these gases, providing insight into guest binding positions, nature of host-guest or guest-guest interactions, and their phase transformations upon exposure to these gases. Combining with theoretical investigation, we have fully elucidated the crossover sorption in the flexible coordination networks, which involves a reversal of apparent affinity and uptake of similar gases at different temperatures. We discovered that this behaviour can be explained by the delicate balance between guest binding and host-guest and guest-guest interactions., (© 2023 Wiley-VCH GmbH.)

Developing artificial porous systems with high molecular recognition performance is critical but very challenging to achieve selective uptake of a particular component from a mixture of many similar species, regardless of the size and affinity of these competing species. A porous platform that integrates multiple recognition mechanisms working cooperatively for highly efficient guest identification is desired. Here, we designed a flexible porous coordination polymer (PCP) and realised a corrugated channel system that cooperatively responds to only target gas molecules by taking advantage of its stereochemical shape, location of binding sites, and structural softness. The binding sites and structural deformation act synergistically, exhibiting exclusive discrimination gating (EDG) effect for selective gate-opening adsorption of CO 2 over nine similar gas molecules, including N 2 , CH 4 , CO, O 2 , H 2 , Ar, C 2 H 6 , and even higher-affinity gases such as C 2 H 2 and C 2 H 4 . Combining in-situ crystallographic experiments with theoretical studies, it is clear that this unparalleled ability to decipher the CO 2 molecule is achieved through the coordination of framework dynamics, guest diffusion, and interaction energetics. Furthermore, the gas co-adsorption and breakthrough separation performance render the obtained PCP an efficient adsorbent for CO 2 capture from various gas mixtures., (© 2023. The Author(s).)

Incorporating strong electron donor functionality into flexible coordination networks is intriguing for sorption applications due to a built-in mechanism for electron-withdrawing guests. Here we report a 2D flexible porous coordination network, [Ni 2 (4,4'-bipyridine)(VTTF) 2 ]n(1) (where H 2 VTTF = 2,2'-[1,2-bis(4-benzoic acid)-1,2ethanediylidene]bis-1,3-benzodithiole), which exhibits large structural deformation from the as-synthesized or open phase (1α) into the closed phase (1β) after guest removal, as demonstrated by X-ray and electron diffraction. Interestingly, upon exposure to electron-withdrawing species, 1β reversibly undergoes guest accommodation transitions; 1α⊃O 2 (90 K) and 1α⊃N 2 O (185 K). Moreover, the 1β phase showed exclusive O 2 sorption over other gases (N 2 , Ar, and CO) at 120 K. The phase transformations between the 1α and 1β phases under these gases were carefully investigated by in-situ X-ray diffraction, in-situ spectroscopic studies, and DFT calculations, validating that the unusual sorption was attributed to the combination of flexible frameworks and VTTF (electron-donor) that induces strong interactions with electron-withdrawing species., (© 2023. The Author(s).)

Xylene isomers are crucial chemical intermediates in great demand worldwide; the almost identical physicochemical properties render their current separation approach energy consuming. In this study, we utilized the soft porous coordination polymer (PCP)'s isomer-specific structural transformation, realizing o -xylene (oX) recognition/separation from the binary and ternary isomer mixtures. This PCP has a flexible structure that contains flexible aromatic pendant groups, which both work as recognition sites and induce structural flexibility of the global framework. The PCP exhibits guest-triggered "breathing"-type structural changes, which are accompanied by the rearrangement of the intraframework π-π interaction. By rebuilding π-π stacking with isomer species, the PCP discriminated oX from the other isomers by its specific guest-loading configuration and separated oX from the isomer mixture via selective adsorption. The xylene-selective property of the PCP is dependent on the solvent; in diluted hexane solution, the PCP favors p -xylene (pX) uptake. The separation results combined with crystallographic analyses revealed the effect of the isomer selectivity of the PCP on xylene isomer separation via structural transition and demonstrated its potential as a versatile selective adsorptive medium for challenging separations.

Two-dimensional (2D) π-conjugated conductive metal-organic frameworks ( c MOFs, 2DπcMOF) with modulated channel sizes and a broad conductivity range have been reported in the last decade. In contrast, the corresponding comparative studies on their effects on chemiresistive sensing performances, which measure the resistive response toward external chemical stimuli, have not yet been reported. In this work, we sought to explore the structure-performance relationships of honeycomb-like 2D π-conjugated c MOF chemiresistive gas sensors with channel sizes less than 2 nm (the mass transport issue) and broad conductivity in the range from ∼10 -8 S cm -1 to 1 S cm -1 (the charge transport issue). As a result, we found that the c MOF with a lower conductivity facilitates the much more sensitive response toward the charge transfer of the adsorbed gases (relative increases in resistance: R = 63.5% toward 100 ppm of NH 3 for the as prepared Cu-THQ sensor with the conductivity of ∼10 -8 S cm -1 ). Interestingly, the cMOF with a medium channel size (Cu-THHP-THQ) exhibited the fastest response speed in sensing, although it contains H 2 en 2+ as neutralizing counterions in the channels. From the evaluation of the pore size distribution, it is found that the overall porosity (meso- & micro-pores) of c MOFs, rather than the pore size of the honeycomb structure, would determine their sensing speed. When comparing the performance of two different morphologies of nanorods (NRs) and nanosheets (NSs), NRs showed a slower response and extended recovery time, which can be ascribed to the slower gas diffusion in the more extended 1D channel. Altogether, our results demonstrate the first systematic studies on the effect of various structural parameters on the chemiresistive sensor performance of c MOFs.

Background: Plexiform schwannoma is one of the least common variants of schwannoma, accounting for only 5% of all schwannoma cases. It generally occurs in the skin and subcutaneous tissues and is uncommon in deep soft tissue or viscera. We present an extremely rare case of plexiform schwannoma arising from the peripancreatic plexus., Case Presentation: A 29-year-old man presented with hyperglycemia detected during a medical checkup. He was diagnosed with type 1 diabetes based on the clinical findings and laboratory tests. During the diagnostic process for diabetes, a 2.5 cm mass was incidentally detected in the pancreas by abdominal ultrasound. Contrast-enhanced computed tomography revealed a mass that was gradually enhanced at the body and tail of the pancreas. Magnetic resonance imaging revealed low signal intensity of the mass on T1-weighted images and high signal intensity on T2-weighted and diffusion-weighted images. Magnetic resonance cholangiopancreatography showed no abnormal findings in the main pancreatic duct. Endoscopic ultrasonography (EUS) showed a lobulated, low-echoic mass with a clear boundary. EUS-guided fine needle biopsy was performed, and spindle-shaped cells that were diffusely immunopositive for S-100 and negative for c-kit and desmin were detected, resulting in a diagnosis of a neurogenic tumor arising from the pancreas or the peripancreatic nerve plexus. The patient underwent laparoscopic spleen-preserving distal pancreatectomy. Although the tumor was connected to the splenic plexus, the splenic artery could be divided along its adventitial plane. Macroscopic findings of the excised tumor consisted of multiple yellowish-white nodules, and its histopathological features were consistent with plexiform schwannoma. There was no pancreatic tissue on the dorsal surface of the tumor, which suggested that the tumor arose from the peripancreatic nerve plexus., Conclusions: The findings documented herein can aid in the differential diagnosis of peripancreatic schwannoma and in planning appropriate treatment., (© 2021. The Author(s).)

A 61-year-old man was examined for cervical pain and CT showed a 9 cm tumor to the third part of the duodenum and proximal jejunum. CT /MRI showed that the tumor was separated from the pancreas body. We scheduled a laparoscopic partial resection of the intestine with a suspected diagnosis of GIST of the intestine. The tumor was adhered to both the proximal jejunum and uncinate process of the pancreas. Therefore, we converted to an open surgery and resected part of the pancreas, duodenum, and proximal jejunum including the tumor. Histopathological examination showed the tumor capsule included the tissue of the pancreas and that the border between the intestine and the tumor was clear, suggesting that the origin of the tumor was the pancreas. We diagnosed the patient as having a grade 2 pancreatic neuroendocrine tumor based on the tumor growth pattern and immunohistochemistry findings. We examined the preoperative CT images retrospectively and found that the tumor had adhered to the uncinate process of the pancreas, which extends over the left side of the superior mesenteric artery. When GIST close to the proximal jejunum is suspected, the possibility of pancreatic neuroendocrine tumor should be considered.

A 73-year-old man visited our hospital with the chief complaints of anorexia and weight loss. Computed tomography showed a 5 cm tumor(diameter)in the sigmoid mesocolon. We performed laparoscopic Hartmann operation; however, because of sacral invasion of tumor, curative surgery was difficult. Therefore, the tumor was excised together with the sigmoid colon. Histopathological examination of the tumor confirmed the diagnosis of epithelioid sarcoma. Postoperatively, the patient received heavy-particle radiotherapy at another facility as treatment for the residual tumor. The size of the residual tumor decreased 6 months after the surgery. Up until 1 year after surgery, the patient's condition has remained stable without any disease progression. Epithelioid sarcoma is a rare soft-tissue tumor and often leads to a poor prognosis. We present a case of epithelioid sarcoma occurring in the sigmoid mesocolon.

Background: The influence of chronic kidney disease (CKD) on the outcome of gastric cancer surgery has rarely been reported., Methods: Retrospectively collected clinicopathological data on patients who underwent elective gastrectomy between January 2007 and December 2014 were analyzed (n = 500). The patients were divided into 2 groups based on the preoperative estimated glomerular filtration rate (eGFR): a non-CKD group (eGFR ≥60 ml/min/1.73 m2, n = 392) and a CKD group (eGFR <60 ml/min/1.73 m2, n = 108). Short- and long-term results of the surgery were compared., Results: There was no significant difference between the 2 groups in terms of the overall morbidity rate (p = 0.215), and in any kind of postoperative complication, including infectious and cardiovascular complications. Additionally, there was no significant difference in the morbidity rate irrespective of the type of gastrectomy and the extent of lymph node dissection. The 3-year relapse-free survival rates in the non-CKD and CKD groups were 92.1 and 92.0%, respectively, in stage I disease (p = 0.640), 81.4 and 73.7%, respectively, in stage II disease (p = 0.825), and 35.9 and 31.9%, respectively, in stage III disease (p = 0.784)., Conclusion: CKD did not affect the short- and long-term outcomes in patients after gastric cancer surgery., (© 2016 S. Karger AG, Basel.)

Background: The present study assessed conservative management of acute cholecystitis (AC) with a focus on percutaneous transhepatic gallbladder aspiration (PTGBA)., Methods: Consecutive 275 patients with AC who underwent PTGBA were reviewed. Patients aged ≥80 years and/or with American Society of Anesthesiologists score III to IV and/or performance status 3 to 4 were defined as high risk. Patients were classified according to duration from symptom onset to first PTGBA: within 3 days (early PTGBA) or over 3 days (late PTGBA). They were also classified according to duration from first PTGBA to surgery: within 30 days (early surgery) or over 30 days (late surgery)., Results: A total of 263 patients (95.6%) showed recovery after PTGBA. There were no significant differences in operating time, blood loss, operating procedure, conversion rate to open surgery, postoperative complications, or postoperative hospital stay between the early and late PTGBA groups or between the early and late surgery groups. No significant complications associated with PTGBA or surgery were observed, including in those at high risk., Conclusions: Percutaneous transhepatic gallbladder aspiration can be a useful alternative for most patients with AC, including those at high risk. Elective cholecystectomy can be performed safely regardless of the timing of PTGBA or surgery., (© 2016 Japanese Society of Hepato-Biliary-Pancreatic Surgery.)

A 69-year-old man with a malignant tumor of the stomach underwent distal gastrectomy with partial resection of the abdominal wall, transverse colon, and lateral segment of the liver. Based on a detailed pathological examination of the resected specimen, a diagnosis of undifferentiated gastric cancer was established. Six months after the operation, during postoperative adjuvant chemotherapy with S-1, diagnostic imaging, including CT and positron emission tomography (PET), revealed a portal vein tumor thrombus and diffusely spreading metastases in the posterior segment of the liver. Despite chemotherapy with S-1/CDDP, the metastatic tumors continued to grow rapidly. The patient died 10 months after the operation. On autopsy, the portal vein tumor thrombus was observed to be composed of undifferentiated cancer cells invading into the liver parenchyma through hepatic sinusoids, with the metastatic tumors replacing 60% or more of the entire liver.

Introduction: The inferior mesenteric artery is usually divided during the resection of sigmoid colon cancers. However, this sometimes results in an insufficient blood supply to the anastomosis, leading to anastomotic leakage. We conducted a retrospective analysis to determine the feasibility and potential benefits of preserving the superior rectal artery (SRA)., Methods: Fifty-seven patients underwent SRA-preserving sigmoidectomy with D2 or D3 lymph node dissection (group A) between June 2008 and May 2012. These patients were compared with 35 patients who underwent sigmoidectomy without preservation of the SRA (group B) during the same period., Results: The amount of blood loss, the number of harvested lymph nodes, and the postoperative morbidity rate did not differ significantly between the groups. There were no cases of anastomotic leakage in group A and there was one in group B, but this difference was not significant. The 3-year relapse-free survival rates also did not differ significantly between the two groups, irrespective of lymph node status., Conclusion: Sigmoidectomy with SRA preservation can be performed without compromising the quality of lymph node dissection and relapse-free survival. No advantage of preserving the SRA could be demonstrated, but it is noteworthy that no anastomotic leakage was noted among the 57 patients in group A., (© 2014 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd.)