Clinical Outcomes of Secondary Duodenal Self-Expandable Metallic Stenting for Duodenal Stent Dysfunction in Patients with Malignant Duodenal Obstruction: A Retrospective Multicenter Study.

Background/Aims: Malignant duodenal obstruction has become more common with the development of palliative therapies.The outcomes of endoscopic ultrasound-guided gastrojejunostomy (EUS-GJ) are comparable to those of surgical gastrojejunostomy or duodenal stenting. However, EUS-GJ is technically challenging. Duodenal self-expandable metallic stent (SEMS) placement is popular; however, obstructions are common. Duodenal SEMS obstruction can be managed with the insertion of a second SEMS in a stent-in-stent manner. Therefore, we aimed to analyze the clinical outcomes of secondary duodenal SEMS placement in patients with malignant duodenal obstruction. Methods: We retrospectively analyzed the data of patients who underwent secondary duodenal stent insertion for duodenal stent dysfunction between January 2016 and December 2021. The primary outcome was stent patency. The secondary outcomes were clinical success, factors associated with dysfunction, patient survival, and adverse events. Results: A total of 109 patients were included. The mean age was 64.4±11.2 years, and 63 patients (57.8%) were male. Ninety-two patients (84.4%) had pancreaticobiliary cancer. Clinical success was achieved in 94 cases (86.2%). Twenty-three patients experienced stent dysfunction with 231 days of median stent patency (95% confidence interval [CI], 169 to not available). After a multivariable Cox hazard analysis of stent patency, the Eastern Cooperative Oncology Group performance status (hazard ratio [HR], 2.13; 95% CI, 1.20 to 3.81; p=0.010) and the first stent patency ≥6 months (HR, 0.33; 95% CI, 0.11 to 0.95; p=0.050) remained significant associated factors. Adverse events occurred in five patients (4.6%). Conclusions: Secondary duodenal stent insertion is a viable option for first duodenal stent obstruction. Further comparative studies involving surgery or EUS-GJ for obstructed duodenal stents are warranted.

Long-term outcomes of fully covered self-expandable metal stents for refractory biliary strictures after living donor liver transplantation: a retrospective study at a tertiary center.

BACKGROUND AND AIMS: Endoscopic multiple plastic stents are an established first-line treatment for anastomotic biliary stricture (ABS) management after liver transplantation (LT). Fully covered self-expandable metallic stents (FCSEMSs) have recently been used with favorable outcomes, but long-term treatment outcomes remain an issue for ABS. We evaluated the long-term outcomes of FCSEMS for the management of refractory ABS after LT. METHODS: We reviewed the prospectively collected and maintained endoscopic retrograde cholangiography database at Asan Medical Center to retrieve consecutive post-LT ABS cases that underwent an endoscopic FCSEMS placement between August 2009 and August 2019 after MPS placement failure. RESULTS: A total of 34 patients were enrolled in this study. Technical success had been achieved in all subjects (100%). The median stent placement duration was 3.1 months (IQR 2.7-6.1). Stricture resolution was achieved in 26 patients (clinical success 76.5%, 95% confidence interval 62-91). Early adverse events developed in 3 patients (8.8%), including distal stent migration. Late adverse events occurred in 9 patients (26.5%), including cholangitis (n = 7, 20.6%) and asymptomatic distal stent migration (n = 2, 5.9%). The median follow-up period was 57.9 months (IQR 51.9-64.3). Stricture recurrence occurred in 3 of 26 patients who achieved clinical success (11.5%). CONCLUSIONS: FCSEMS placement appears to be an effective and advisable intervention for refractory ABS as it can provide persistent stricture improvement over the long-term.

Fiber-based quantum-dot pulse oximetry for wearable health monitoring with high wavelength selectivity and photoplethysmogram sensitivity.

Increasing demand for real-time healthcare monitoring is leading to advances in thin and flexible optoelectronic device-based wearable pulse oximetry. Most previous studies have used OLEDs for this purpose, but did not consider the side effects of broad full-width half-maximum (FWHM) characteristics and single substrates. In this study, we performed SpO2 measurement using a fiber-based quantum-dot pulse oximetry (FQPO) system capable of mass production with a transferable encapsulation technique, and a narrow FWHM of about 30 nm. Based on analyses we determined that uniform angular narrow FWHM-based light sources are important for accurate SpO2 measurements through multi-layer structures and human skin tissues. The FQPO was shown to have improved photoplethysmogram (PPG) signal sensitivity with no waveguide-mode noise signal, as is typically generated when using a single substrate (30-50%). We successfully demonstrate improved SpO2 measurement accuracy as well as all-in-one clothing-type pulse oximetry with FQPO.

High-Performance and Reliable White Organic Light-Emitting Fibers for Truly Wearable Textile Displays.

Light-emitting fibers have been intensively developed for the realization of textile displays and various lighting applications, as promising free-form electronics with outstanding interconnectivity. These advances in the fiber displays have been made possible by the successful implementation of the core technologies of conventional displays, including high optoelectronic performance and essential elements, in the fiber form-factor. However, although white organic light-emitting diodes (WOLEDs), as a fundamental core technology of displays, are essential for realizing full-color displays and solid-state lighting, fiber-based WOLEDs are still challenging due to structural issues and the lack of approaches to implementing WOLEDs on fiber. Herein, the first fiber WOLED is reported, exhibiting high optoelectronic performance and a reliable color index, comparable to those of conventional planar WOLEDs. As key features, it is found that WOLEDs can be successfully introduced on a cylindrical fiber using a dip-coatable single white-emission layer based on simulation and optimization of the white spectra. Furthermore, to ensure durability from usage, the fiber WOLED is encapsulated by an Al2 O3 /elastomer bilayer, showing stable operation under repetitive bending and pressure, and in water. This pioneering work is believed to provide building blocks for realizing complete textile display technologies by complementing the lack of the core technology.

Synthesis of α,ß-unsaturated ketones through nickel-catalysed aldehyde-free hydroacylation of alkynes.

α,ß-Unsaturated ketones are common feedstocks for the synthesis of fine chemicals, pharmaceuticals, and natural products. Transition metal-catalysed hydroacylation reactions of alkynes using aldehydes have been recognised as an atom-economical route to access α,ß-unsaturated ketones through chemoselective aldehydic C-H activation. However, the previously reported hydroacylation reactions using rhodium, cobalt, or ruthenium catalysts require chelating moiety-bearing aldehydes to prevent decarbonylation of acyl-metal-hydride complexes. Herein, we report a nickel-catalysed anti-Markovnikov selective coupling process to afford non-tethered E-enones from terminal alkynes and S-2-pyridyl thioesters in the presence of zinc metal as a reducing agent. Utilization of a readily available thioester as an acylating agent and water as a proton donor enables the mechanistically distinctive and aldehyde-free hydroacylation of terminal alkynes. This non-chelation-controlled approach features mild reaction conditions, high step economy, and excellent regio- and stereoselectivity.

Recent Progress of Fiber Shaped Lighting Devices for Smart Display Applications-A Fibertronic Perspective.

Advances in material science and nanotechnology have fostered the miniaturization of devices. Over the past two decades, the form-factor of these devices has evolved from 3D rigid, volumetric devices through 2D film-based flexible electronics, finally to 1D fiber electronics (fibertronics). In this regard, fibertronic strategies toward wearable applications (e.g., electronic textiles (e-textiles)) have attracted considerable attention thanks to their capability to impart various functions into textiles with retaining textiles' intrinsic properties as well as imperceptible irritation by foreign matters. In recent years, extensive research has been carried out to develop various functional devices in the fiber form. Among various features, lighting and display features are the highly desirable functions in wearable electronics. This article discusses the recent progress of materials, architectural designs, and new fabrication technologies of fiber-shaped lighting devices and the current challenges corresponding to each device's operating mechanism. Moreover, opportunities and applications that the revolutionary convergence between the state-of-the-art fibertronic technology and age-long textile industry will bring in the future are also discussed.

Modulation of Growth Kinetics of Vacuum-Deposited CsPbBr3 Films for Efficient Light-Emitting Diodes.

Because of its excellent optical properties and good stability, all-inorganic halide perovskite CsPbX3 (X = I, Br, Cl) has been attracting interest for use in light-emitting diodes (LEDs). One challenge is improving the efficacy of the spatial confinement of excitons for higher luminescence efficiency. Here, we present a simple yet very effective strategy to form fine-grain-structured CsPbBr3 polycrystalline films prepared by thermal co-evaporation. The strategy involves controlling growth kinetics by adjusting the deposition rate, which, along with growth temperature, determines the nucleation rate and therefore the eventual grain structure. A correlation between deposition rate and average grain size was noted except for a very large deposition rate when there were large hillocks, which we attributed to the peculiar growth behavior of PbBr2 films. The growth conditions that produced a nanoscale grain structure and textured orientations without large hillocks also resulted in the highest luminescence efficiency as we anticipated. With the optimized CsPbBr3 light emitters, we demonstrate a green-light-emitting (at 524 nm) LED with a maximum current efficiency of 1.07 cd/A and an extremely narrow electroluminescence spectrum of 18 nm, a result that highlights the potential of vacuum-processed CsPbBr3 films for high-efficiency LEDs.

Is Reconstruction Preserving the First Ray or First Two Rays Better Than Full Transmetatarsal Amputation in Diabetic Foot?

BACKGROUND: The benefits of total transmetatarsal amputation over higher level amputation are well known. However, there are no studies evaluating the effects of first ray- or first two ray-sparing transmetatarsal amputation with flap coverage. The authors evaluated this approach with regard to functional outcome and to identify long-term complications. METHODS: Retrospective data of 59 patients were evaluated according to their surgical method. Complete transmetatarsal amputation with free flap reconstruction was designated as the transmetatarsal amputation group with 27 patients and first ray- or first two ray-preserving transmetatarsal amputation with free flap reconstruction was designated as the ray group, with 32 patients. Demographics, flap outcomes, additional procedures after initial healing, and functional outcomes were measured and evaluated. RESULTS: There was no statistically significant difference in demographic distribution and flap outcomes in either group, except for poor blood glucose control in the ray group. Additional procedures after initial healing showed no statistical difference, but the tendency of minor procedures was higher in the ray group. The maximum achieved ambulatory function was significantly better in the ray group, with an ambulatory function score of 4.4 compared with 3.7 in the transmetatarsal amputation group (p = 0.012). CONCLUSIONS: The preservation of the first ray or first two rays with free flap reconstruction may functionally benefit the patients despite the higher tendency toward minor procedures after initial healing. Furthermore, the progressive deformity of the preserved first and second toes will inevitably occur, requiring patients to undergo further surgery. Further studies are warranted to evaluate this approach. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Weavable and Highly Efficient Organic Light-Emitting Fibers for Wearable Electronics: A Scalable, Low-Temperature Process.

Fiber-based wearable displays, one of the most desirable requisites of electronic textiles (e-textiles), have emerged as a technology for their capability to revolutionize textile and fashion industries in collaboration with the state-of-the-art electronics. Nonetheless, challenges remain for the fibertronic approaches, because fiber-based light-emitting devices suffer from much lower performance than those fabricated on planar substrates. Here, we report weavable and highly efficient fiber-based organic light-emitting diodes (fiber OLEDs) based on a simple, cost-effective and low-temperature solution process. The values obtained for the fiber OLEDs, including efficiency and lifetime, are similar to that of conventional glass-based counterparts, which means that these state-of-the-art, highly efficient solution processed planar OLEDs can be applied to cylindrical shaped fibers without a reduction in performance. The fiber OLEDs withstand tensile strain up to 4.3% at a radius of 3.5 mm and are verified to be weavable into textiles and knitted clothes by hand-weaving demonstrations. Furthermore, to ensure the scalability of the proposed scheme fiber OLEDs with several diameters of 300, 220, 120, and 90 µm, thinner than a human hair, are demonstrated successfully. We believe that this approach, suitable for cost-effective reel-to-reel production, can realize low-cost commercially feasible fiber-based wearable displays in the future.

Highly Flexible and Efficient Fabric-Based Organic Light-Emitting Devices for Clothing-Shaped Wearable Displays.

Recently, the role of clothing has evolved from merely body protection, maintaining the body temperature, and fashion, to advanced functions such as various types of information delivery, communication, and even augmented reality. With a wireless internet connection, the integration of circuits and sensors, and a portable power supply, clothes become a novel electronic device. Currently, the information display is the most intuitive interface using visualized communication methods and the simultaneous concurrent processing of inputs and outputs between a wearer and functional clothes. The important aspect in this case is to maintain the characteristic softness of the fabrics even when electronic devices are added to the flexible clothes. Silicone-based light-emitting diode (LED) jackets, shirts, and stage costumes have started to appear, but the intrinsic stiffness of inorganic semiconductors causes wearers to feel discomfort; thus, it is difficult to use such devices for everyday purposes. To address this problem, a method of fabricating a thin and flexible emitting fabric utilizing organic light-emitting diodes (OLEDs) was developed in this work. Its flexibility was evaluated, and an analysis of its mechanical bending characteristics and tests of its long-term reliability were carried out.

A New Approach for Reconstruction of Diabetic Foot Wounds Using the Angiosome and Supermicrosurgery Concept.

BACKGROUND: Major vessels in the diabetic foot are often calcified and inadequate for use as recipient vessels. Thus, a supermicrosurgery technique using small branches or perforators from other collateral vessels with an adequate pulse may be an alternative method. This study evaluated outcome using the supermicrosurgery concept and the risk factors involved. METHODS: Ninety-five cases of diabetic foot reconstruction were reviewed; the average patient age was 57 years; average follow-up was 43.5 months. Débridement was performed according to the angiosome concept, and reconstruction was performed with perforator flaps using the supermicrosurgery approach. Correlation between total flap loss and 16 preoperative risk factors (age, sex, diabetes mellitus type, smoking, immunosuppression, flap size, hemoglobin A1c, ankle-brachial index, preoperative transcutaneous partial pressure of oxygen, C-reactive protein, computed tomographic angiography, amputation history, peripheral artery disease, American Society of Anesthesiologists physical status, osteomyelitis, and chronic renal failure) were analyzed. RESULTS: Of 95 cases, nine cases of total loss and 12 of minor complication were noted. Among the risk factors, the odds for failure after peripheral artery disease was 10.99 (p = 0.035), and that associated with a history of amputation was 9.44 (0.0006). Other factors had no correlation with flap loss, including cases with no or one major vessel. Flap survival rate was 90.5 percent, and the overall limb salvage rate was 93.7 percent. CONCLUSIONS: Despite the high risk of failure related to peripheral artery disease and history of amputation, the supermicrosurgery approach using a recipient vessel with good pulsation regardless of the source can achieve limb salvage. This approach extends the possibility for reconstruction in patients with severe ischemic diabetic foot. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Diabetic foot reconstruction using free flaps increases 5-year-survival rate.

The purpose of this study was to evaluate the outcome of the diabetic foot reconstructed with free flaps and analyse the preoperative risk factors. This study reviews 121 cases of reconstructed diabetic foot in 113 patients over 9 years (average follow-up of 53.2 months). Patients' age ranged from 26 to 78 years (average, 54.6 years). Free flaps used were anterolateral thigh (ALT, 90), superficial circumflex iliac artery perforator (SCIP, 20), anteromedial thigh (AMT, 5), upper medial thigh (UMT, 3), and other perforator free flaps (3). Correlation between the surgical outcome and preoperative risk factors were analysed using logistic regression model. Total loss was seen in 10 cases and 111 free-tissue transfers were successful (flap survival rate of 91.7%). During follow-up, limb was eventually lost in 17 patients and overall limb salvage rate was 84.9% and the 5-year survival was 86.8%. Correlation between flap loss and 14 preoperative risk factors (computed tomography (CT) angiogram showing intact numbers of major vessels, history of previous angioplasty, peripheral arterial disease (PAD), heart problem, chronic renal failure (CRF), American Society of Anaesthesiologists (ASA) physical status classification system, smoking, body mass index (BMI), HBA1c, lymphocyte count, ankle-brachial index (ABI), osteomyelitis, C-reactive protein (CRP) level and whether taking immunosuppressive agents) were analysed. Significant odds ratio were seen in patients who underwent lower extremity angioplasties (odds ratio: 17.590, p<0.001), with PAD (odds ratio: 10.212, p=0.032) and taking immunosuppressive agents after kidney transplantation (odds ratio: 4.857, p<0.041). Diabetic foot reconstruction using free flaps has a high chance for success and significantly increases the 5-year survival rate. Risk factors such as PAD, history of angioplasties in the extremity and using immunosuppressive agents after transplant may increase the chance for flap loss.

Conditional ambiguity of one-dimensional crystal structures determined from a minimum of diffraction intensity data.

When the number of intensities greatly exceeds the number of unknown atomic coordinates, the problem of obtaining a crystal structure from the intensities is overdetermined and, for a sufficiently small structure, a chemically meaningful solution can be found by direct methods. A difficulty in determining a structure has been historically attributed to the non-uniqueness of such a structure owing to multiple, or homometric, structures that yield the same set of intensities. The number of homometric structures has not been rigorously analyzed owing to the complexity of this problem. By using the method of elementary symmetric polynomials with a new origin definition, one-dimensional crystal structures of a small number of identical atoms (N < 5), determined from a minimum (N - 1) of the lowest-resolution intensities, are enumerated. It is demonstrated that such a structure is unique for N ≤ 3. Interestingly, for N = 4, the structure can be determined either uniquely or twofold ambiguously, depending on the intensity values. These results suggest that, even for larger structures, a minimum set of (or not many more) accurately measured intensities can yield a unique structure.

Distribution of lengths of the normal femur and tibia in Korean children from three to sixteen years of age.

To develop a standard growth curve of the lower extremity in Korean children from 3 to 16 yr of age, the lengths from a total of 2087 normal long bone segments (582 femurs and 645 tibias in boys, and 417 femurs and 443 tibias in girls) were measured. Children were grouped by years of bone age, which was determined by using the Korean specific bone age standard; TW2-20 method. The growth spurt occurred in girls from eight to eleven years by bone age, and in boys from eleven to thirteen years. The mean tibial length relative to the mean femoral length was 0.78 in boys and 0.79 in girls. The overall growth pattern was similar to that observed in American children in the 1960s. Korean children and adolescents appear to have a different tempo of skeletal maturation during pubertal growth from that of English and American children and adolescents. The Korean standard growth curve and the Korean bone age chart allow determination of the presence of any existent growth abnormalities and prediction of future remaining growth in lower extremities. These normative growth standards can be used for leg-length equalization purposes in children with anisomelia.