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1.
Am J Transplant ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38428639

RESUMO

In living-donor liver transplantation, biliary complications including bile leaks and biliary anastomotic strictures remain significant challenges, with incidences varying across different centers. This multicentric retrospective study (2016-2020) included 3633 adult patients from 18 centers and aimed to identify risk factors for these biliary complications and their impact on patient survival. Incidences of bile leaks and biliary strictures were 11.4% and 20.6%, respectively. Key risk factors for bile leaks included multiple bile duct anastomoses (odds ratio, [OR] 1.8), Roux-en-Y hepaticojejunostomy (OR, 1.4), and a history of major abdominal surgery (OR, 1.4). For biliary anastomotic strictures, risk factors were ABO incompatibility (OR, 1.4), blood loss >1 L (OR, 1.4), and previous abdominal surgery (OR, 1.7). Patients experiencing biliary complications had extended hospital stays, increased incidence of major complications, and higher comprehensive complication index scores. The impact on graft survival became evident after accounting for immortal time bias using time-dependent covariate survival analysis. Bile leaks and biliary anastomotic strictures were associated with adjusted hazard ratios of 1.7 and 1.8 for graft survival, respectively. The study underscores the importance of minimizing these risks through careful donor selection and preoperative planning, as biliary complications significantly affect graft survival, despite the availability of effective treatments.

2.
Surg Endosc ; 38(4): 2116-2123, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38438678

RESUMO

BACKGROUND: Recently, the outcomes of surgical treatment for advanced hepatocellular carcinoma (HCC) have improved. However, despite the technical advancements in laparoscopic liver resection (LLR), it is still not recommended as the standard treatment for HCC with portal vein tumor thrombosis (PVTT) because of the poor oncological outcomes. This study aims to compare the clinical outcomes of open liver resection (OLR) and LLR in patients with HCC with PVTT. METHODS: A total of 86 patients with PVTT confirmed in the pathological report between January 2014 and December 2018, were enrolled. Short-term, postoperative, and long-term outcomes, including recurrence-free survival and overall survival rates, were evaluated. RESULTS: No difference between the two groups, except for age, was detected. The median age in the laparoscopic group was significantly higher than that in the open group. Regarding the pathological features, the maximal tumor size was significantly larger in the OLR; other pathological factors did not differ. There was no significant difference between overall survival (OS) and recurrence-free survival (RFS). Vp3 PVTT (hazards ratio [HR] 6.1, 95% confidence interval [CI] 1.9-18.5), Edmondson grade IV (HR 4.7, 95% CI 1.7-12.9, p = 0.003), and intrahepatic metastasis (HR 3.9, 95% CI 2.1-7.2, p < 0.001) remained the unique independent predictors of recurrence-free survival according to a multivariate Cox proportional hazard regression analysis. CONCLUSIONS: Laparoscopic liver resection for the management of HCC with PVTT provides the same short- and long-term results as those of the open approach.


Assuntos
Carcinoma Hepatocelular , Laparoscopia , Neoplasias Hepáticas , Trombose Venosa , Humanos , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/cirurgia , Veia Porta/cirurgia , Veia Porta/patologia , Estudos Retrospectivos , Trombose Venosa/etiologia , Trombose Venosa/cirurgia , Hepatectomia , Resultado do Tratamento
3.
Ann Surg ; 278(5): 798-806, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37477016

RESUMO

OBJECTIVE: To define benchmark values for adult-to-adult living-donor liver transplantation (LDLT). BACKGROUND: LDLT utilizes living-donor hemiliver grafts to expand the donor pool and reduce waitlist mortality. Although references have been established for donor hepatectomy, no such information exists for recipients to enable conclusive quality and comparative assessments. METHODS: Patients undergoing LDLT were analyzed in 15 high-volume centers (≥10 cases/year) from 3 continents over 5 years (2016-2020), with a minimum follow-up of 1 year. Benchmark criteria included a Model for End-stage Liver Disease ≤20, no portal vein thrombosis, no previous major abdominal surgery, no renal replacement therapy, no acute liver failure, and no intensive care unit admission. Benchmark cutoffs were derived from the 75th percentile of all centers' medians. RESULTS: Of 3636 patients, 1864 (51%) qualified as benchmark cases. Benchmark cutoffs, including posttransplant dialysis (≤4%), primary nonfunction (≤0.9%), nonanastomotic strictures (≤0.2%), graft loss (≤7.7%), and redo-liver transplantation (LT) (≤3.6%), at 1-year were below the deceased donor LT benchmarks. Bile leak (≤12.4%), hepatic artery thrombosis (≤5.1%), and Comprehensive Complication Index (CCI ® ) (≤56) were above the deceased donor LT benchmarks, whereas mortality (≤9.1%) was comparable. The right hemiliver graft, compared with the left, was associated with a lower CCI ® score (34 vs 21, P < 0.001). Preservation of the middle hepatic vein with the right hemiliver graft had no impact neither on the recipient nor on the donor outcome. Asian centers outperformed other centers with CCI ® score (21 vs 47, P < 0.001), graft loss (3.0% vs 6.5%, P = 0.002), and redo-LT rates (1.0% vs 2.5%, P = 0.029). In contrast, non-benchmark low-volume centers displayed inferior outcomes, such as bile leak (15.2%), hepatic artery thrombosis (15.2%), or redo-LT (6.5%). CONCLUSIONS: Benchmark LDLT offers a valuable alternative to reduce waitlist mortality. Exchange of expertise, public awareness, and centralization policy are, however, mandatory to achieve benchmark outcomes worldwide.


Assuntos
Doença Hepática Terminal , Hepatopatias , Transplante de Fígado , Trombose , Adulto , Humanos , Doadores Vivos , Benchmarking , Doença Hepática Terminal/cirurgia , Resultado do Tratamento , Estudos Retrospectivos , Índice de Gravidade de Doença , Hepatopatias/complicações , Sobrevivência de Enxerto
4.
Small ; 19(18): e2206428, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36732849

RESUMO

Self-assembly process represents one of the most powerful and efficient methods for designing functional nanomaterials. For generating optimal functional materials, understanding the pathway complexity during self-assembly is essential, which involves the aggregation of molecules into thermodynamically or kinetically favored pathways. Herein, a functional perylene diimide (PDI) derivative by introducing diacetylene (DA) chains (PDI-DA) is designed. Temperature control pathway complexity with the evolution of distinct morphology for the kinetic and thermodynamic product of PDI-DA is investigated in detail. A facile strategy of UV-induced polymerization is adopted to trap and capture metastable kinetic intermediates to understand the self-assembly mechanism. PDI-DA showed two kinetic intermediates having the morphology of nanosheets and nanoparticles before transforming into the thermodynamic product having fibrous morphology. Spectroscopic studies revealed the existence of distinct H- and J-aggregates for kinetic and thermodynamic products respectively. The polymerized fibrous PDI-DA displayed reversible switching between J-aggregate and H-aggregate.

5.
Org Biomol Chem ; 21(31): 6302-6306, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37490038

RESUMO

A new triggered self-assembly method, which utilizes retro Diels-Alder (rDA)-promoted self-assembly of a macrocyclic diacetylene, was developed. The steric bulk present in a Diels-Alder (DA) adduct was released by a thermally promoted rDA reaction, resulting in the generation of a linear diacetylene that readily self-assembles to form a supramolecular polymer. The maleimide-containing blue-colored polydiacetylene, which was generated by UV irradiation, was utilized as a thiol specific colorimetric sensor.

6.
Transpl Infect Dis ; 25(4): e14070, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37254966

RESUMO

BACKGROUND: Cytomegalovirus (CMV) is a frequent infectious complication following solid organ transplantation (SOT). Considering significant differences in healthcare systems, a systematic review was conducted to describe the epidemiology, management, and burden of CMV post-SOT in selected countries outside of Europe and North America. METHODS: MEDLINE, Embase, and Cochrane databases were searched for observational studies in SOT recipients across 15 countries in the regions of Asia, Pacific, and Latin America (search period: January 1, 2011 to September 17, 2021). Outcomes included incidence of CMV infection/disease, recurrence, risk factors, CMV-related mortality, treatment patterns and guidelines, refractory and/or resistant CMV, patient-reported outcomes, and economic burden. RESULTS: Of 2708 studies identified, 49 were eligible (n = 43/49; 87.8% in adults; n = 34/49, 69.4% in kidney recipients). Across studies, selection of CMV preventive strategy was based on CMV serostatus. Overall, rates of CMV infection (within 1 year) and CMV disease post-SOT were respectively, 10.3%-63.2% (9 studies) and 0%-19.0% (17 studies). Recurrence occurred in 35.4%-41.0% cases (3 studies) and up to 5.3% recipients died of CMV-associated causes (11 studies). Conventional treatments for CMV infection/disease included ganciclovir (GCV) or valganciclovir. Up to 4.4% patients were resistant to treatment (3 studies); no studies reported on refractory CMV. Treatment-related adverse events with GCV included neutropenia (2%-29%), anemia (13%-48%), leukopenia (11%-37%), and thrombocytopenia (13%-24%). Data on economic burden were scarce. CONCLUSION: Outside of North America and Europe, rates of CMV infection/disease post-SOT are highly variable and CMV recurrence is frequent. CMV resistance and treatment-associated adverse events, including myelosuppression, highlight unmet needs with conventional therapy.


Assuntos
Infecções por Citomegalovirus , Leucopenia , Transplante de Órgãos , Adulto , Humanos , Citomegalovirus , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/epidemiologia , Europa (Continente)/epidemiologia , América do Norte/epidemiologia , Ganciclovir , Transplante de Órgãos/efeitos adversos
7.
World J Surg ; 47(6): 1540-1546, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36723663

RESUMO

BACKGROUND: Transfusion of allogeneic blood products can have adverse effects and profoundly influence postoperative liver transplantation outcomes, including graft survival. To minimize allogeneic red blood cell (RBC) transfusion, salvaged blood can be used during liver transplantation. The aim of this study was to determine the contribution of salvaged blood to allogeneic RBC transfusion in living donor liver transplantation (LDLT) recipients. METHODS: Data of 311 adult-to-adult LDLT recipients between January 2015 and April 2019 were analyzed. The primary outcome was a change in requirement for allogeneic RBCs due to the use of salvaged blood. Additionally, predictors of intraoperative allogeneic RBC transfusion were investigated. RESULTS: One hundred fifty-three (49.2%) recipients required allogeneic RBC transfusion. If recipients did not receive salvaged blood, 253 (81.4%) recipients would have needed allogeneic RBC transfusion. The total volume of salvaged blood transfused into recipients during surgery was 269,165 mL, which corresponded to 993 units of allogeneic RBCs and accounted for 76.1% of total RBC transfusion volume. Multivariate analysis showed that male recipients, model for end-stage liver disease score, preoperative hemoglobin level, and volume of salvaged blood used during surgery were independent predictors of the need for intraoperative allogenic RBC transfusion. CONCLUSIONS: Intraoperative use of salvaged blood significantly reduced allogeneic RBC transfusion in LDLT recipients. It can help transplant teams manage transfusion of allogeneic RBCs during liver transplantation.


Assuntos
Doença Hepática Terminal , Transplante de Fígado , Adulto , Humanos , Masculino , Transfusão de Eritrócitos/efeitos adversos , Doadores Vivos , Índice de Gravidade de Doença
8.
J Korean Med Sci ; 38(35): e277, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667582

RESUMO

Living liver donors (LLDs) are screened for transmissible diseases including cancer. We investigated the actual cancer incidence of LLDs compared with a matched healthy control group from the general Korean population using data from the Korean National Health Insurance Services (NHIS). A total of 12,372 LLDs who donated a liver graft between 2002 and 2018 were registered in the Korean Network for Organ Sharing. They were compared to a matched healthy control group selected from the Korean NHIS. Cancer diagnosis was identified in 175 LLDs (1.4%) and 1,014 controls (0.8%). Compared to the healthy control group, the incidence rate ratio of liver and thyroid cancer in the LLD group were significantly higher at 18.30 and 1.39, respectively. The incidences of 11 other specified cancers were not different between the two groups. The present study suggests that LLD after donor hepatectomy may require medical surveillance, especially for liver cancer.


Assuntos
Transplante de Fígado , Neoplasias da Glândula Tireoide , Humanos , Incidência , Hepatectomia , Fígado
9.
J Korean Med Sci ; 38(16): e121, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37096307

RESUMO

BACKGROUND: Liver transplant (LT) recipients were considered a vulnerable population during the coronavirus disease 2019 (COVID-19) pandemic. The clinical efficacy of the COVID-19 vaccine is unknown in immunocompromised patients. The purpose of this study was to provide evidence of antibody responses after COVID-19 vaccination in LT recipients. METHODS: This study enrolled 46 patients who underwent LT at Samsung Medical Center (Seoul, Korea) before implementation of the one-dose vaccine in Korea. Those who completed the two-dose COVID-19 vaccine between August 2021 and September 2021 were included and followed through December 2021. Semiquantitative anti-spike serologic testing was performed using the Roche Elecsys anti-SARS-CoV-2 S enzyme immunoassay (Roche Diagnostics, Rotkereuz, Switzerland) with a positive cutoff of at least 0.8 U/mL. RESULTS: Among all 46 participants, 40 (87%) demonstrated an antibody response after the second dose of a COVID-19 vaccine, while six (13%) had no antibody response after the second dose. Upon univariate analysis, patients with higher antibody titer had longer years since LT (2.3 ± 2.8 vs. 9.4 ± 5.0, P < 0.001). A lower median tacrolimus (TAC) level before vaccination and after the second dose of COVID-19 vaccine indicated a significantly higher antibody response (2.3 [1.6-3.2] vs. 7.0 [3.7-7.8], P = 0.006, 2.5 [1.6-3.3] vs. 5.7 [4.2-7.2], P = 0.003). Period between 2nd vaccination and serologic testing was significantly higher in the antibody-response group compared to the no-antibody-response group (30.2 ± 24.0 vs. 65.9 ± 35.0, P = 0.012). A multivariate analysis of antibody responses revealed TAC level before vaccination as a statistically significant factor. CONCLUSION: A higher TAC level before vaccination resulted in less effective vaccination in LT patients. Booster vaccinations are required, especially for patients in the early stage after LT who have compromised immune function.


Assuntos
COVID-19 , Transplante de Fígado , Humanos , Vacinas contra COVID-19 , Vacinação , Imunização Secundária , Anticorpos , Tacrolimo , Anticorpos Antivirais , Transplantados
10.
Sensors (Basel) ; 23(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36850804

RESUMO

Human-machine interfaces (HMI) refer to the physical interaction between a user and rehabilitation robots. A persisting excessive load leads to soft tissue damage, such as pressure ulcers. Therefore, it is necessary to define a comfortable binding part for a rehabilitation robot with the subject in a standing posture. The purpose of this study was to quantify the comfort at the binding parts of the standing rehabilitation robot. In Experiment 1, cuff pressures of 10-40 kPa were applied to the thigh, shank, and knee of standing subjects, and the interface pressure and pain scale were obtained. In Experiment 2, cuff pressures of 10-20 kPa were applied to the thigh, and the tissue oxygen saturation and the skin temperature were measured. Questionnaire responses regarding comfort during compression were obtained from the subjects using the visual analog scale and the Likert scale. The greatest pain was perceived in the thigh. The musculoskeletal configuration affected the pressure distribution. The interface pressure distribution by the binding part showed higher pressure at the intermuscular septum. Tissue oxygen saturation (StO2) increased to 111.9 ± 6.7% when a cuff pressure of 10 kPa was applied and decreased to 92.2 ± 16.9% for a cuff pressure of 20 kPa. A skin temperature variation greater than 0.2 °C occurred in the compressed leg. These findings would help evaluate and improve the comfort of rehabilitation robots.


Assuntos
Robótica , Humanos , Posição Ortostática , Coxa da Perna , Postura , Dor
11.
J Am Chem Soc ; 144(39): 17889-17896, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36126329

RESUMO

High-resolution structures are crucial for understanding the functional properties of nanomaterials. We applied single-particle cryo-electron microscopy (cryo-EM), a method traditionally used for structure determination of biological macromolecules, to obtain high-resolution structures of synthetic non-biological filaments formed by photopolymerization of macrocyclic diacetylene (MDA) amphiphilic monomers. Tomographic analysis showed that the MDA monomers self-assemble into hollow nanotubes upon dispersion in water. Single-particle analysis revealed tubes consisting of six pairs of covalently bonded filaments held together by hydrophobic interactions, where each filament is composed of macrocyclic rings stacked in parallel "chair" conformations. The hollow MDA nanotube structures we found may account for the efficient scavenging of amphiphilic pollutants in water and subsequent photodegradation of the guest species.


Assuntos
Poluentes Ambientais , Nanotubos , Microscopia Crioeletrônica/métodos , Polímero Poliacetilênico , Água
12.
Sensors (Basel) ; 22(16)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36015868

RESUMO

Workers at construction sites are prone to fall-from-height (FFH) accidents. The severity of injury can be represented by the acceleration peak value. In the study, a risk prediction against FFH was made using IMU sensor data for accident prevention at construction sites. Fifteen general working movements (NF: non-fall), five low-hazard-fall movements, (LF), and five high-hazard-FFH movements (HF) were performed by twenty male subjects and a dummy. An IMU sensor was attached to the T7 position of the subject to measure the three-axis acceleration and angular velocity. The peak acceleration value, calculated from the IMU data, was 4 g or less in general work movements and 9 g or more in FFHs. Regression analysis was performed by applying various deep learning models, including 1D-CNN, 2D-CNN, LSTM, and Conv-LSTM, to the risk prediction, and then comparing them in terms of their mean absolute error (MAE) and mean squared error (MSE). The FFH risk level was estimated based on the predicted peak acceleration. The Conv-LSTM model trained by MAE showed the smallest error (MAE: 1.36 g), and the classification with the predicted peak acceleration showed the best accuracy (97.6%). This study successfully predicted the FFH risk levels and could be helpful to reduce fatal injuries at construction sites.


Assuntos
Aprendizado Profundo , Aceleração , Prevenção de Acidentes , Humanos , Masculino , Movimento
13.
Sensors (Basel) ; 22(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36298335

RESUMO

sEMG-based gesture recognition is useful for human-computer interactions, especially for technology supporting rehabilitation training and the control of electric prostheses. However, high variability in the sEMG signals of untrained users degrades the performance of gesture recognition algorithms. In this study, the hand posture recognition algorithm and radar plot-based visual feedback training were developed using multichannel sEMG sensors. Ten healthy adults and one bilateral forearm amputee participated by repeating twelve hand postures ten times. The visual feedback training was performed for two days and five days in healthy adults and a forearm amputee, respectively. Artificial neural network classifiers were trained with two types of feature vectors: a single feature vector and a combination of feature vectors. The classification accuracy of the forearm amputee increased significantly after three days of hand posture training. These results indicate that the visual feedback training efficiently improved the performance of sEMG-based hand posture recognition by reducing variability in the sEMG signal. Furthermore, a bilateral forearm amputee was able to participate in the rehabilitation training by using a radar plot, and the radar plot-based visual feedback training would help the amputees to control various electric prostheses.


Assuntos
Amputados , Membros Artificiais , Adulto , Humanos , Antebraço , Eletromiografia/métodos , Retroalimentação Sensorial , Mãos , Gestos , Algoritmos , Postura
14.
Angew Chem Int Ed Engl ; 61(43): e202211465, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36045485

RESUMO

Creation of new two-dimensional (2D) architectures has attracted significant attention in the field of self-assembly for structural diversity and new functionalization. Although numerous 2D polymer nanosheets have been reported, 2D nanosheets with tubular channels have been unexplored. Herein, we describe a new strategy for the fabrication of stimulus-responsive conjugated polymer 2D nanosheets with hollow cavities. Amphiphilic macrocyclic diacetylenes self-assembled in an aqueous solution in a columnar manner to afford bilayered 2D nanosheets with intrinsically tubular nanochannels. UV-induced polymerization resulted in the generation of blue-colored tubular conjugated polydiacetylene 2D nanosheets. Immobilization of gold nanoparticles, fluorescence labeling with FRET phenomenon and colorimetric DNA sensing were demonstrated with these new 2D nanosheets. In addition, the free NH2 containing polymerized 2D nanosheet was utilized for conductivity behavior and grafting on graphene oxide (GO).


Assuntos
Nanopartículas Metálicas , Polímeros Responsivos a Estímulos , Ouro , Polímeros/química , Colorimetria
15.
Sensors (Basel) ; 21(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34300378

RESUMO

In this study, algorithms to detect post-falls were evaluated using the cross-dataset according to feature vectors (time-series and discrete data), classifiers (ANN and SVM), and four different processing conditions (normalization, equalization, increase in the number of training data, and additional training with external data). Three-axis acceleration and angular velocity data were obtained from 30 healthy male subjects by attaching an IMU to the middle of the left and right anterior superior iliac spines (ASIS). Internal and external tests were performed using our lab dataset and SisFall public dataset, respectively. The results showed that ANN and SVM were suitable for the time-series and discrete data, respectively. The classification performance generally decreased, and thus, specific feature vectors from the raw data were necessary when untrained motions were tested using a public dataset. Normalization made SVM and ANN more and less effective, respectively. Equalization increased the sensitivity, even though it did not improve the overall performance. The increase in the number of training data also improved the classification performance. Machine learning was vulnerable to untrained motions, and data of various movements were needed for the training.


Assuntos
Acidentes por Quedas , Redes Neurais de Computação , Algoritmos , Humanos , Aprendizado de Máquina , Masculino , Máquina de Vetores de Suporte
16.
Sensors (Basel) ; 21(22)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34833756

RESUMO

Surface electromyography (sEMG)-based gesture recognition systems provide the intuitive and accurate recognition of various gestures in human-computer interaction. In this study, an sEMG-based hand posture recognition algorithm was developed, considering three main problems: electrode shift, feature vectors, and posture groups. The sEMG signal was measured using an armband sensor with the electrode shift. An artificial neural network classifier was trained using 21 feature vectors for seven different posture groups. The inter-session and inter-feature Pearson correlation coefficients (PCCs) were calculated. The results indicate that the classification performance improved with the number of training sessions of the electrode shift. The number of sessions necessary for efficient training was four, and the feature vectors with a high inter-session PCC (r > 0.7) exhibited high classification accuracy. Similarities between postures in a posture group decreased the classification accuracy. Our results indicate that the classification accuracy could be improved with the addition of more electrode shift training sessions and that the PCC is useful for selecting the feature vector. Furthermore, hand posture selection was as important as feature vector selection. These findings will help in optimizing the sEMG-based pattern recognition algorithm more easily and quickly.


Assuntos
Gestos , Mãos , Algoritmos , Eletrodos , Eletromiografia , Humanos , Postura , Processamento de Sinais Assistido por Computador
17.
Langmuir ; 36(46): 13971-13980, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33175557

RESUMO

Supramolecular gels originating from the hierarchical self-assembly of low molecular weight organic molecules is a strongly emerging field of advanced material research for the fabrication of soft functional materials. Herein, a novel supramolecular gel was fabricated through the protonation-triggered unidirectional self-assembly of pyridine-attached macrocyclic diacetylene (PyMCDA). Basic nitrogen of a pyridine ring with a strong affinity toward proton transforms the neutral PyMCDA into gelator in its protonated pyridinium salt form (PyMCDA-H+), which further evolves to nano-fibrillar networks to yield a supramolecular gel. Under the irradiation of UV light, the white color gel turned to a robust covalently cross-linked blue-phase PDA gel. Interestingly, polymeric PyMCPDA-H+ gel exhibits a naked-eye detectable reversible blue-red colorimetric response for alternating acid/base (H2SO4/NH4OH) and colorimetric sensitivity toward selected anions: CH3COO-, CN-, HCOO-, and CH3CH2COO-. It is with the hope that this work point toward the utility and versatility of macrocyclic PDAs for constructing chromogenic supramolecular gels for their possible use in sensing systems.

18.
Surg Endosc ; 34(12): 5312-5319, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31834512

RESUMO

BACKGROUND: Anastomotic complications such as leaks, bleeding, and stricture remain the most serious complications of surgery for gastric cancer. No perfect method exists for an accurate and reliable prevention of these complications. This study investigated the safety and efficacy of post-anastomotic intraoperative endoscopy (PAIOE) for avoidance of early anastomotic complications during gastrectomy in gastric cancer. METHODS: This retrospective case-control study enrolled patients from a tertiary care, academic medical center. Routine PAIOE was performed on 319 patients undergoing gastrectomy for gastric cancer between 2015 and 2016. As controls, without PAIOE 270 patients from 2013 to 2014 were used for comparison. Early anastomotic complications and outcomes after PAIOE were determined. RESULTS: Although there were no differences between the PAIOE and non-PAIOE group in terms of overall complication rates (20.1% vs 26.7%; P > 0.05), there were fewer complications related to anastomosis (3.4% vs 8.9%; P < 0.01) in the PAIOE group. The PAIOE group had rates of 2.5% for anastomotic leakage, 0.9% for intra-luminal bleeding, and 0% for anastomotic stenosis, while the non-PAIOE group exhibited rates of 5.6%, 2.6%, and 0.7%, respectively. Thirty-one abnormalities were detected in 26 PAIOE patients (9.71%) (20 venous bleeding, 7 mucosal tearing, 2 air leaks, 1 arterial bleeding, and 1 anastomotic stricture). All abnormalities were corrected by proper interventions (13 reinforced additional suture, 13 endoscopic hemostasis, and 2 re-anastomosis). There were no morbidities associated with PAIOE. CONCLUSIONS: PAIOE appears to be a safe and reliable procedure to evaluate the stability of gastrointestinal anastomosis for gastric cancer patients. Further data collection and a well-designed prospective study are needed to confirm the validity of PAIOE.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Endoscopia Gastrointestinal/métodos , Gastrectomia/efeitos adversos , Neoplasias Gástricas/cirurgia , Anastomose Cirúrgica/métodos , Estudos de Casos e Controles , Feminino , Gastrectomia/métodos , Humanos , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias Gástricas/patologia
19.
Sensors (Basel) ; 20(18)2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32962282

RESUMO

Many safety accidents can occur in industrial sites. Among them, falls from heights (FFHs) are the most frequent accidents and have the highest fatality rate. Therefore, some existing studies have developed personal wearable airbags to mitigate the damage caused by FFHs. To utilize these airbags effectively, it is essential to detect FFHs before collision with the floor. In this study, an inertial measurement unit (IMU) sensor attached to the seventh thoracic vertebrae (T7) was used to develop an FFH detection algorithm. The vertical angle and vertical velocity were calculated using the inertial data obtained from the IMU sensor. Forty young and healthy males were recruited to perform non-FFH and FFH motions. In addition, experiments using a human mannequin and dynamics simulations were performed to obtain FFH data at heights above 2 m. The developed algorithm achieved 100% FFH detection accuracy and provided sufficient lead time such that the airbags could be inflated completely before collision with the floor.


Assuntos
Acidentes por Quedas , Algoritmos , Movimento (Física) , Saúde Ocupacional , Acidentes por Quedas/prevenção & controle , Humanos , Masculino , Manequins
20.
Sensors (Basel) ; 20(5)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32111090

RESUMO

Fall-related injury is a common cause of mortality among the elderly. Hip fractures are especially dangerous and can even be fatal. In this study, a threshold-based preimpact fall detection algorithm was developed for wearable airbags that minimize the impact of falls on the user's body. Acceleration sum vector magnitude (SVM), angular velocity SVM, and vertical angle, calculated using inertial data captured from an inertial measurement unit were used to develop the algorithm. To calculate the vertical angle accurately, a complementary filter with a proportional integral controller was used to minimize integration errors and the effect of external impacts. In total, 30 healthy young men were recruited to simulate 6 types of falls and 14 activities of daily life. The developed algorithm achieved 100% sensitivity, 97.54% specificity, 98.33% accuracy, and an average lead time (i.e., the time between the fall detection and the collision) of 280.25 ± 10.29 ms with our experimental data, whereas it achieved 96.1% sensitivity, 90.5% specificity, and 92.4% accuracy with the SisFall public dataset. This paper demonstrates that the algorithm achieved a high accuracy using our experimental data, which included some highly dynamic motions that had not been tested previously.


Assuntos
Acidentes por Quedas , Algoritmos , Dispositivos Eletrônicos Vestíveis , Acelerometria , Atividades Cotidianas , Air Bags , Humanos , Masculino , Movimento (Física) , Máquina de Vetores de Suporte , Fatores de Tempo , Adulto Jovem
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