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1.
BMC Cancer ; 24(1): 874, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039481

RESUMO

BACKGROUND: For patients with rectal cancer, the utilization of temporary ileostomy (TI) has proven effective in minimizing the occurrence of severe complications post-surgery, such as anastomotic leaks; however, some patients are unable to reverse in time or even develop a permanent stoma (PS). We aimed to determine the preoperative predictors associated with TS failure and develop and validate appropriate predictive models to improve patients' quality of life. METHODS: This research included 403 patients with rectal cancer who underwent temporary ileostomies between January 2017 and December 2021. All patients were randomly divided into either the developmental (70%) or validation (30%) group. The independent risk factors for PS were determined using univariate and multivariate logistic regression analyses. Subsequently, a nomogram was constructed, and the prediction probability was estimated by calculating the area under the curve (AUC) using receiver operating characteristic (ROC) analysis. A calibration plot was used to evaluate the nomogram calibration. RESULTS: Of the 403 enrolled patients, 282 were randomized into the developmental group, 121 into the validation group, and 58 (14.39%) had a PS. The development group consisted of 282 patients, of whom 39 (13.81%) had a PS. The validation group consisted of 121 patients, of whom, 19 (15.70%) had a PS; 37 related factors were analyzed in the study. Multivariate logistic regression analysis demonstrated significant associations between the occurrence of PS and various factors in this patient cohort, including tumor location (OR = 6.631, P = 0.005), tumor markers (OR = 2.309, P = 0.035), American Society of Anesthesiologists (ASA) score (OR = 4.784, P = 0.004), T4 stage (OR = 2.880, P = 0.036), lymph node metastasis (OR = 4.566, P = 0.001), and distant metastasis (OR = 4.478, P = 0.036). Furthermore, a preoperative nomogram was constructed based on these data and subsequently validated in an independent validation group. CONCLUSION: We identified six independent preoperative risk factors associated with PS following rectal cancer resection and developed a validated nomogram with an area under the ROC curve of 0.7758, which can assist surgeons in formulating better surgical options, such as colostomy, for patients at high risk of PS.


Assuntos
Ileostomia , Nomogramas , Neoplasias Retais , Humanos , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Feminino , Masculino , Ileostomia/efeitos adversos , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Estomas Cirúrgicos/efeitos adversos , Qualidade de Vida , Curva ROC , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Adulto
2.
Surg Endosc ; 38(7): 3531-3546, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38816619

RESUMO

BACKGROUND: Central pancreatectomy is a surgical procedure for benign and low-grade malignant tumors which located in the neck and proximal body of the pancreas that facilitates the preservation of pancreatic endocrine and exocrine functions but has a high morbidity rate, especially postoperative pancreatic fistula (POPF). The aim of this systematic review and meta-analysis was to evaluate the safety and effectiveness between minimally invasive central pancreatectomy (MICP) and open central pancreatectomy (OCP) basing on perioperative outcomes. METHODS: An extensive literature search to compare MICP and OCP was conducted from October 2003 to October 2023 on PubMed, Medline, Embase, Web of Science, and the Cochrane Library. Fixed-effect models or random effects were selected based on heterogeneity, and pooled odds ratios (ORs) or mean differences (MDs) with 95% confidence intervals (CIs) were calculated. RESULTS: A total of 10 studies with a total of 510 patients were included. There was no significant difference in POPF between MICP and OCP (OR = 0.95; 95% CI [0.64, 1.43]; P = 0.82), whereas intraoperative blood loss (MD = - 125.13; 95% CI [- 194.77, -55.49]; P < 0.001) and length of hospital stay (MD = - 2.86; 95% CI [- 5.00, - 0.72]; P = 0.009) were in favor of MICP compared to OCP, and there was a strong trend toward a lower intraoperative transfusion rate in MICP than in OCP (MD = 0.34; 95% CI [0.11, 1.00]; P = 0.05). There was no significant difference in other outcomes between the two groups. CONCLUSION: MICP was as safe and effective as OCP and had less intraoperative blood loss and a shorter length of hospital stay. However, further studies are needed to confirm the results.


Assuntos
Pancreatectomia , Neoplasias Pancreáticas , Complicações Pós-Operatórias , Humanos , Pancreatectomia/métodos , Pancreatectomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Neoplasias Pancreáticas/cirurgia , Fístula Pancreática/etiologia , Fístula Pancreática/prevenção & controle , Fístula Pancreática/epidemiologia , Tempo de Internação/estatística & dados numéricos , Resultado do Tratamento , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Laparoscopia/métodos
3.
World J Surg Oncol ; 22(1): 94, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38610000

RESUMO

BACKGROUND: Temporary ileostomy (TI) has proven effective in reducing the severity of anastomotic leakage after rectal cancer surgery; however, some ileostomies fail to reverse over time, leading to conversion into a permanent stoma (PS). In this study, we aimed to investigate the preoperative risk factors and cumulative incidence of TI non-closure after sphincter-preserving surgery for rectal cancer. MATERIALS AND METHODS: We conducted a meta-analysis after searching the Embase, Web of Science, PubMed, and MEDLINE databases from their inception until November 2023. We collected all published studies on the risk factors related to TI non-closure after sphincter-preserving surgery for rectal cancer. RESULTS: A total of 1610 studies were retrieved, and 13 studies were included for meta-analysis, comprising 3026 patients. The results of the meta-analysis showed that the identified risk factors included older age (p = 0.03), especially > 65 years of age (p = 0.03), male sex (p = 0.009), American Society of Anesthesiologists score ≥ 3 (p = 0.004), comorbidity (p = 0.001), and distant metastasis (p < 0.001). Body mass index, preoperative hemoglobin, preoperative albumin, preoperative carcinoma embryonic antigen, tumor location, neoadjuvant chemoradiotherapy, smoking, history of abdominal surgery, and open surgery did not significantly change the risk of TI non-closure. CONCLUSION: We identified five preoperative risk factors for TI non-closure after sphincter-preserving surgery for rectal cancer. This information enables surgeons to identify high-risk groups before surgery, inform patients about the possibility of PS in advance, and consider performing protective colostomy or Hartmann surgery.


Assuntos
Neoplasias Retais , Estomas Cirúrgicos , Humanos , Masculino , Ileostomia/efeitos adversos , Incidência , Fatores de Risco , Neoplasias Retais/cirurgia
4.
J Dairy Sci ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39004137

RESUMO

The lack of fat in yogurt can lead to alterations in taste and whey separation, reducing consumer acceptance. In this study, the feasibility of enhancing the quality of skim milk yogurt through a combination of transglutaminase (TG) and protein-glutaminase (PG) was investigated. The combination of TG and PG resulted in simultaneous cross-linking and deamidated of casein micelles, with PG deamidation taking priority over TG cross-linking, leading to higher solubility and lower turbidity of milk proteins compared with TG alone. When 0.06 U/mL TG and 0.03 U/mL PG were added, firmness and viscosity indexes significantly increased by 38.26 and 78.59%, respectively as compared with the control. Microscopic images revealed increased cross-linking with casein and filling of cavities by smaller sub-micelles in the combination of TG and PG treatment. Furthermore, the combination of TG and PG resolved issues of rough taste and whey separation, leading to improved overall liking. This study highlights the benefits of using both enzymes in dairy production and has important implication for future research.

5.
Sensors (Basel) ; 24(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39001101

RESUMO

With the development of technology, people's demand for pressure sensors with high sensitivity and a wide working range is increasing. An effective way to achieve this goal is simulating human skin. Herein, we propose a facile, low-cost, and reproducible method for preparing a skin-like multi-layer flexible pressure sensor (MFPS) device with high sensitivity (5.51 kPa-1 from 0 to 30 kPa) and wide working pressure range (0-200 kPa) by assembling carbonized fabrics and micro-wrinkle-structured Ag@rGO electrodes layer by layer. In addition, the highly imitated skin structure also provides the device with an extremely short response time (60/90 ms) and stable durability (over 3000 cycles). Importantly, we integrated multiple sensor devices into gloves to monitor finger movements and behaviors. In summary, the skin-like MFPS device has significant potential for real-time monitoring of human activities in the field of flexible wearable electronics and human-machine interaction.


Assuntos
Fibra de Algodão , Pressão , Dispositivos Eletrônicos Vestíveis , Humanos , Fibra de Algodão/análise , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Eletrodos , Pele , Têxteis , Atividades Humanas
6.
HPB (Oxford) ; 26(4): 476-485, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38195309

RESUMO

BACKGROUND: The aim of this study was to investigate whether pedicled ligament flaps (PLF) covering around the hepatic and gastroduodenal artery stump can provide better clinical outcomes in pancreatoduodenectomy (PD). METHODS: We conducted a comprehensive search of databases (inception to January 2023) to identify studies comparing PD with or without PLF covering the skeletonized arteries. The perioperative and postoperative outcomes were compared. Pooled odds ratios (ORs) with 95 % confidence intervals (CIs) were calculated using fixed-effects models. RESULTS: Ten studies were included in the qualitative synthesis. Six studies with 3538 patients met the inclusion criteria for the meta-analysis. Patients in the PLF group had a significantly lower rate of PPH from the hepatic artery or gastroduodenal artery stump (H/G PPH) (OR: 0.41; 95 % CI, 0.22-0.75; P < 0.01) and overall PPH (OR: 0.65; 95 % CI, 0.46-0.93; P = 0.02). There were no significant differences between the two groups in terms of morbidity, grade B/C postoperative pancreatic fistula (B/C POPF), delayed gastric emptying (DGE), reoperation, or mortality. CONCLUSION: Prophylactic pedicled ligament flaps covering around the skeletonized arteries significantly reduced overall PPH and H/G PPH, and it seemed to have no obvious influence on other complications.

7.
Oncologist ; 28(7): e575-e584, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35930304

RESUMO

BACKGROUND: Systemic chemotherapy is the primary treatment in patients with locally advanced or metastatic pancreatic ductal adenocarcinoma (PDAC). More effective treatment options are highly awaited. The aim of this study was to evaluate the toxicity and feasibility of gemcitabine/nab-paclitaxel/S-1 (GAS) chemotherapy on a 21-day cycle in patients with locally advanced or metastatic PDAC, determine the dose-limiting toxicity (DLT) and the maximum tolerated dose (MTD) of S-1 in this regimen, and explore preliminary efficacy. METHODS: Eligible patients with locally advanced or metastatic PDAC received GAS chemotherapy on a 21-day cycle. Fixed-dose nab-paclitaxel (125 mg/m2) and gemcitabine (1000 mg/m2) were given intravenously on days 1 and 8. Different doses of S-1 were given orally twice daily from day 1 to day 14 in a 3+3 dose escalation design. According to patients` body surface area, the dose-escalation design was as follows: patients with a body surface area of 1.25-1.5 m2 received S-1 40 mg/day initially and the dose was increased to 60 mg or 80 mg. Patients with a body surface area of more than 1.5 m2 received S-1 60 mg/day initially and the dose was increased to 80 mg or 100 mg. The primary endpoints were to evaluate the toxicity and determine the DLT and MTD of S-1. The secondary endpoint was to evaluate efficacy, including best objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). adverse events (AEs) were evaluated according to the NCI-CTCAE 5.0. Tumor response was assessed using the RECIST 1.1. RESULTS: A total of 21 eligible patients were included. Due to the infrequence of patients with a body surface area of 1.25-1.5 m2, only 2 patients were included in cohort of S-1 40 mg. The dose-escalation for patients in this group failed to be enrolled completely. For patients with a body surface area of more than 1.5 m2, 3 DLTs in 7 patients were detected at cohort of S-1 100 mg (grade 3 thrombocytopenia with hemorrhage, grade 3 rash, and grade 3 mucositis/stomatitis). S-1 80 mg/day (body surface area: >1.5 m2) was considered to be the MTD in GAS chemotherapy on a 21-day cycle. No grade 4 AEs or treatment-related deaths were observed. The most commonly occurring hematologic AE of any grade was anemia (38.1%). The most frequent nonhematologic AEs of any grade were peripheral neuropathy (38.1%), dyspepsia (23.8%), constipation (23.8%), and alopecia (23.8%). Response assessment showed that the best ORR was 36.8% (7 of 19 patients) and the DCR was 94.7% (18 of 19 patients). The median PFS was 5.3 (95% CI, 4.6 to 6.0) months and the median OS was 10.3 (95% CI, 8.1 to 12.5) months. CONCLUSION: GAS chemotherapy (21-day cycle) with nab-paclitaxel 125 mg/m2, gemcitabine 1000 mg/m2, and S-1 80 mg/day (body surface area: >1.5 m2) was found to have acceptable toxicity and significant clinical control in patients with locally advanced or metastatic PDAC. We conclude that further trials with this combination are warranted. (Trial Identifier: ChiCTR1900027833 [chictr.org]).


Assuntos
Adenocarcinoma , Gencitabina , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Paclitaxel , Adenocarcinoma/patologia , Neoplasias Pancreáticas
8.
Opt Lett ; 48(24): 6368-6371, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099750

RESUMO

In this Letter, we present an experimental demonstration of downstream signaling in a 16 × 50 Gbit/s coherent passive optical network (CPON) using the code and space division multiplexing (CDM-SDM) approach. We realize optical SDM through the utilization of a 4-core weakly coupled multicore fiber (WC-MCF), enhancing the total available optical launch power at the optical line terminal (OLT). This enhancement significantly improves the power budget for CPONs that connect with a large number of optical network units (ONUs). At the second stage of the CPON, four CDM-assigned ONUs are connected to individual cores of the WC-MCF, thereby supporting the connectivity of up to 16 ONUs. Through experiments, we have noted substantial disparities in the downstream signaling performance among individual CDM-assigned ONUs, particularly as the capacity is increased to 800 Gbit/s. To address this issue, we have employed an innovative approach by leveraging space-time coding techniques to manipulate the CDM tributaries, to achieve a balanced reception performance for all ONUs within the CPON. We believe that the proposed CDM-SDM CPON scheme, complemented by the advanced DSP flow chart, holds significant promise for future PON systems characterized by substantial capacity and extensive connectivity.

9.
Biomacromolecules ; 24(2): 977-990, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36703538

RESUMO

Although photodynamic therapy (PDT) has become an attractive strategy for cancer treatment, its clinical application still suffers from some limitations, including insufficient delivery of photosensitizers, hypoxic tumor environment, and the development of PDT resistance. To address these limitations, a new class of mitochondria-targeting and fluorinated polymer with aggregation-induced emission characteristics was fabricated to sensitize PDT and co-deliver chemotherapeutic drugs. The amphiphilic fluoropolymer was able to efficiently carry oxygen and SN-38 (the active metabolite of irinotecan) and self-assemble into multifunctional micellar nanoparticles (SN-38-TTCF@O2 NPs). Upon internalization into tumor cells, these NPs could successfully escape lysosomes, selectively target mitochondria, efficiently produce reactive oxygen species (ROS) under light irradiation, and release drugs in response to ROS. In the HCT116 tumor xenograft model, they preferentially accumulated in tumor tissue and significantly alleviated tumor hypoxia, resulting in synergistic chemo-PDT efficacy without distinct toxicity. Furthermore, the nanoscale chemo-PDT induced immunogenic cell death, promoted the recruitment and activation of cytotoxic T lymphocytes, and ultimately augmented the anti-tumor efficacy of anti-PD-1 antibody in the murine CT26 tumor model. These results may provide novel insights into the development of efficient chemo-PDT nanomedicine to improve the outcome of immunotherapy.


Assuntos
Nanopartículas , Fotoquimioterapia , Humanos , Camundongos , Animais , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Irinotecano , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/farmacologia , Imunoterapia , Mitocôndrias/metabolismo
10.
Langenbecks Arch Surg ; 408(1): 40, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36652008

RESUMO

PURPOSE: Laparoscopic central pancreatectomy (LCP) has been implemented in pancreatic surgery; however, open surgery is still the predominant approach for central pancreatectomy (CP). Our objective was to compare LCP with open CP (OCP). METHODS: Data were collected from patients with tumours located in the pancreatic neck and proximal body who underwent CP in the Department of Pancreatic Surgery West China Hospital from January 1, 2010, to June 30, 2019. A comparison between the LCP and OCP groups was performed. RESULTS: Fifteen patients underwent CP via the laparoscopic approach, and 96 patients underwent CP via the open approach. Using 1:2 propensity score matching (PSM), 12 patients in the LCP group were matched to 21 in the OCP group. Regarding safety, postoperative pancreatic fistula (POPF) was not significantly different between the two groups (13.3% vs. 12.5%, P = 1.000), even with PSM (16.7% vs. 14.3%, P = 1.000). However, regarding effectiveness, the operative time in the OCP group was significantly shorter than that in the LCP group before (307.0 ± 92.3 ml vs. 220.6 ± 63.6 ml, P < 0.000) and after (300.3 ± 90.2 ml vs. 212.7 ± 44.4 ml, P = 0.002) PSM. Regarding length of stay (LOS), there was no difference between the two groups before (13.1 ± 13.7 days vs. 12.7 ± 10.1 days, P = 0.376) and after PSM (14.4 ± 15.1 days vs. 14.5 ± 16.2 days, P = 0.985). The length of the resected pancreas was shorter in the OCP group than in the LCP group before PSM (50.0 ± 13.2 mm vs. 41.1 ± 11.1 mm, P = 0.043). However, there was no difference between the two groups after PSM (47.9 ± 12.5 mm vs. 37.9 ± 10.4 mm, P = 0.084). Moreover, the other variables showed no difference between the two groups before and after PSM. CONCLUSION: LCP can demonstrate similar safety and effectiveness to OCP, even in the early stages of the learning curve.


Assuntos
Laparoscopia , Neoplasias Pancreáticas , Humanos , Pancreatectomia , Estudos Retrospectivos , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/patologia , Pontuação de Propensão , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Tempo de Internação , Resultado do Tratamento
11.
Opt Lett ; 47(22): 5813-5816, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37219110

RESUMO

An exact modal decomposition method plays an important role in revealing the modal characteristics of a few-mode fiber, and it is widely used in various applications ranging from imaging to telecommunications. Here, ptychography technology is successfully used to achieve modal decomposition of a few-mode fiber. In our method, the complex amplitude information of the test fiber can be recovered by ptychography, and then the amplitude weight of each eigenmode and the relative phase between different eigenmodes can be easily calculated by modal orthogonal projection operations. In addition, we also propose a simple and effective method to realize coordinate alignment. Numerical simulations and optical experiments validate the reliability and feasibility of the approach.

12.
Langenbecks Arch Surg ; 407(2): 835-844, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35178596

RESUMO

PURPOSE: Duodenal gastrointestinal stromal tumors (GISTs) are rare mesenchymal tumors of the gastrointestinal tract. For localized or potentially resectable GISTs, surgery is the first choice. But the important and complex anatomical structure adjacent to the duodenum makes surgical management for duodenal GISTs challenging and few comprehensive surgical strategies have been described. This study aims to provide new comprehensive surgical strategies for duodenal GISTs by summarizing the surgical approaches and outcomes of duodenal GISTs in different locations in our center in the past 11 years. METHODS: Information from patients who underwent surgical resection for duodenal GISTs at our facility during the past 11 years was retrospectively analyzed. RESULTS: Ninety-two patients have received surgical procedures in the facility. Twenty-three, 31, 3, and 35 patients underwent wedge resection, segmental resection, pancreatic head-preserving duodenectomy, and pancreaticoduodenectomy, respectively. The mean operative times were 212.6 (150-270), 260 (180-370), 323 (300-350), and 354.9 (290-490) min; the mean blood loss was 226.1 (100-400), 303.2 (100-600), 500 (400-600), and 582.9 (200-1300) ml, respectively. R0 margins were obtained in 21, 29, 3, and 32 patients, respectively. CONCLUSIONS: For duodenal GISTs without invasion of the ampulla of Vater or the pancreatic head, a limited resection (such as wedge resection, segmental resection, or pancreatic head-preserving duodenectomy) is feasible. For duodenal GISTs with an invasion of the ampulla of Vater or the pancreatic head, a pancreaticoduodenectomy is still necessary.


Assuntos
Ampola Hepatopancreática , Neoplasias Duodenais , Tumores do Estroma Gastrointestinal , Ampola Hepatopancreática/patologia , Ampola Hepatopancreática/cirurgia , Neoplasias Duodenais/patologia , Neoplasias Duodenais/cirurgia , Duodeno/cirurgia , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Pancreaticoduodenectomia , Estudos Retrospectivos
13.
Langenbecks Arch Surg ; 407(1): 313-319, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34537854

RESUMO

BACKGROUND: Although preoperative splenic artery embolism (SAE) has been widely used for splenomegaly, the efficiency and safety of preoperative SAE in patients with sinistral portal hypertension (SPH) is unknown. METHODS: We designed a retrospective cohort of SPH patients who received preoperative SAE in our hospital (February 2018 to September 2020) and compared to those who received splenectomy only, in terms of intraoperative and postoperative outcomes. RESULTS: In all, 59 patients (18 patients received preoperative SAE) were analyzed. The median age was 44.7 years. Preoperative SAE reduced the intraoperative blood loss (637.0 vs. 420.3 ml, P = 0.041) and operation time (174.0 vs. 141.5 min, P = 0.012). The incidence of complications including postoperative pancreatic fistula (POPF), bleeding, and thromboembolism was comparable. Multivariate analysis showed that SAE was a protective factor for intraoperative blood loss and operation time, while prior pancreatic pseudocyst/abscess was a risk factor. CONCLUSIONS: Preoperative SAE could reduce intraoperative blood loss and operation time in SPH patients without increasing the incidence of complications compared to splenectomy only.


Assuntos
Embolia , Embolização Terapêutica , Hipertensão Portal , Adulto , Humanos , Hipertensão Portal/complicações , Hipertensão Portal/cirurgia , Estudos Retrospectivos , Esplenectomia/efeitos adversos , Artéria Esplênica/cirurgia
14.
Opt Lett ; 46(19): 4908-4911, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598231

RESUMO

We demonstrate direct bandwidth measurement of 11-cm-long multimode polymer waveguides based on an optical sampling technique for the first time, to our knowledge. The pulse shape can be recovered after transmission due to the advantages such as high bandwidth and high refresh rate of optical sampling technology. A reduction in averaged bandwidth (bandwidth-length product) from 241 GHz (27 GHz·m) to 180 GHz (20 GHz·m) of straight waveguides is observed when using mode scramblers to fully stimulate the higher-order modes. The effects such as bending and crossing structure of the waveguides on the bandwidth are also investigated. The proposed method is effective for measuring the bandwidth and dispersion of meter- and centimeter-long waveguides, fibers, and optical devices.

15.
Opt Express ; 28(22): 33254-33262, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33114993

RESUMO

In this work, a silicon-integrated edge coupler supporting dual-mode fiber-to-chip coupling was designed and fabricated on 220-nm-thick SOI wafer with standard CMOS-compatible fabrication process. The proposed low-complexity structure consists of a multimode interference and triple-tip inverse taper. Both LP01 and LP11 modes in the few mode fiber (FMF) can be stimulated simultaneously by the edge coupler from TE0 and TE1 modes in silicon waveguide. Such a design is compatible with broadband wavelength division multiplexing and can be scaled up to 4-polarization-mode coupling as well. Using the proposed edge coupler, 2×100-Gbps/lambda PAM4 multimode interface through dual-mode fiber was demonstrated successfully.

16.
BMC Plant Biol ; 19(1): 473, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694537

RESUMO

BACKGROUND: Soil salinization and alkalization are among the major agricultural threats that affect crop productivity worldwide, which are increasing day by day with an alarming rate. In recent years, several halophytes have been investigated for their utilization in soil remediation and to decipher the mechanism of salt-tolerance in these high salt tolerant genetic repositories. Suaeda salsa is an annual halophytic herb in the family Amaranthaceae, displaying high salt and alkali-resistance and having nutritive value. However, the fundamental biological characteristics of this valuable plant remain to be elucidated until today. RESULTS: In this study, we observed the morphology and development of Suaeda salsa, including seed morphology, seed germination, plant morphology, and flower development. Using microscopy, we observed the male and female gametophyte developments of Suaeda salsa. Also, chromosome behaviour during the meiosis of male gametophyte was studied. Eventually, the genome size of Suaeda salsa was estimated through flow cytometry using Arabidopsis as reference. CONCLUSIONS: Our findings suggest that the male and female gametophyte developments of Suaeda salsa are similar to those of the model plant Arabidopsis, and the diploid Suaeda salsa contains nine pairs of chromosomes. The findings also indicate that the haploid genome of Suaeda salsa is approximately 437.5 MB. The observations and results discussed in this study will provide an insight into future research on Suaeda salsa.


Assuntos
Amaranthaceae/genética , Cromossomos de Plantas , Genoma de Planta , Plantas Tolerantes a Sal/genética , Amaranthaceae/anatomia & histologia , Flores/anatomia & histologia , Tamanho do Genoma , Células Germinativas Vegetais/crescimento & desenvolvimento , Tolerância ao Sal/genética , Plantas Tolerantes a Sal/anatomia & histologia
17.
Opt Express ; 27(11): 15433-15443, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31163740

RESUMO

We propose a novel multimode fiber (MMF) with a 30 µm-core and fluorine-doped cladding for both high-speed short wavelength division multiplexing (SWDM) and coarse wavelength division multiplexing (CWDM) transmission. By optimizing the core size, the mode field diameter (MFD) mismatch between the proposed fiber and both the standard single-mode fiber (SMF) and MMF is minimized, which enables the quasi-single mode operation in the CWDM window and a compromised coupling loss with standard MMFs and SMFs. By adopting a fluorine-doped silica cladding, the bandwidth dependence on wavelength of the proposed fiber is minimized, which indicates that the modal bandwidth performance at the longer wavelength can be effectively improved without compromising modal bandwidth at 850 nm. The error-free 100 Gb/s (4×25.78 Gb/s) multimode transmission over 250 meter-long fiber is achieved using a commercially available VCSEL-based SWDM transceiver. The applicable distance can be extended to 300 meters when a biterror rate just below the forward error correction (FEC) threshold of 5×10 -5 is acceptable. Besides, the 100 Gb/s error-free single-mode transmission over 10 km-long fiber was also demonstrated with a commercially available directly modulatedlaser (DML)-based CWDM transceiver. The results imply that the proposed MMF may be useful for large-scale data center applications.

18.
Exp Cell Res ; 361(2): 316-323, 2017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-29111166

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) displays a highly aggressive malignancy and is considered to be an incurable and rapidly lethal disease. MicroRNAs (miRNAs) are small non-coding RNAs of approximately nucleotides that regulate several aspects of tumors pathogenesis, including migration, invasion, metastasis and epithelial-mesenchymal transition. We have found that miR-107 was significantly high expression in PDAC tissues and cells. High miR-107 expression is associated with poor clinicopathological parameters and prognosis in PDAC patients. Deregulated expression of miR-107 in PDAC cells (AsPC-1 and Panc-1) is sufficient to reduce cell migration and invasion, and to induce upregulation of epithelial markers (ß-catenin, ZO-1 and E-cadherin) and a decrease of mesenchymal marker expression (ZEB-1 and vimentin). We also found that the caveolin-1, PTEN and p-Akt expression are modulated by miR-107 in PDAC cells. Moreover, our study clearly demonstrated that deregulated expression of miR-107 inhibited cell migration and invasion and EMT by up-regulation of caveolin-1 and PTEN, and inhibition of PI3K/Akt signaling in PDAC cells. Our study suggested that miR­107 expression might both be a useful indicator of the metastatic potential and provided a new potential therapeutic target in PDAC.


Assuntos
Carcinoma Ductal Pancreático/genética , Caveolina 1/genética , MicroRNAs/genética , PTEN Fosfo-Hidrolase/genética , Neoplasias Pancreáticas/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Idoso , Antígenos CD , Caderinas/genética , Caderinas/metabolismo , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Caveolina 1/metabolismo , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Vimentina/genética , Vimentina/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
19.
Biochim Biophys Acta Mol Basis Dis ; 1863(2): 354-364, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27838489

RESUMO

High-mobility group box 1 (HMGB1) translocation and release, which is involved in several tissue types of ischemia-reperfusion injuries, activate innate immunity by inducing proinflammatory cytokine production through its interaction with toll-like receptors (TLRs). Our objective was to determine the role of HMGB1 and the degree of activation of TLR-related signal transduction pathways in hypoxia/reoxygenation (H/R)-induced proinflammatory cytokine production and intra-islet graft inflammation. After islets are exposed to hypoxia-reoxygenation for 24h, TLR2/4 expression and TLR-mediated signaling was up-regulated in islets, and HMGB1 was translocated from the nucleus to the cytoplasm and released to the extracellular space. With H/R exposure, proinflammatory cytokine production (IL-1ß and TNF-α) and islet injury were significantly increased, and these effects depend on TLR2/4 signaling pathways. Exogenous HMGB1 also induces islet inflammation and increases the phosphorylation of STAT3, p38 and IκBα in wild-type islets. TLR2 deficiency in TLR2-KO islets resulted in the inhibition of IL-1ß production and STAT3/p38 phosphorylation after HMGB1 exposure. TLR4 deficiency in TLR4-KO islets resulted in the inhibition of TNF-α production and IκBα phosphorylation after HMGB1 exposure. Pre-incubation of the STAT3, p38, or NF-κB inhibitors significantly inhibited HMGB1-induced IL-1ß or TNF-α production in islets, but the effect of HMGB1 or H/R-induced islet injury was not counteracted by a separate treatment of the STAT3 inhibitor, p38 inhibitor, or NF-κB inhibitors. HMGB1 inhibition by ethyl pyruvate or blockade by neutralizing antibodies significantly decreased the phosphorylation of STAT3, p38 and IκBα, the production of IL-1ß and TNF-α, and the islet injury in wild-type islets after exposure to H/R and significantly improved early islet graft failure. Thus, our results suggest that HMGB1 released from H/R induced islets works in an autocrine manner to up-regulate STAT or p38 and augment IL-1ß production via TLR2, and up-regulate NF-κB and augment TNF-α production via TLR4 in intra-islet, which are associated with H/R-induced islet injury and early graft failure.


Assuntos
Citocinas/imunologia , Proteína HMGB1/imunologia , Inflamação/etiologia , Transplante das Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/imunologia , Traumatismo por Reperfusão/complicações , Receptores Toll-Like/imunologia , Animais , Hipóxia Celular , Sobrevivência de Enxerto , Inflamação/imunologia , Inflamação/patologia , Ilhotas Pancreáticas/patologia , Transplante das Ilhotas Pancreáticas/patologia , Camundongos Endogâmicos C57BL , Transporte Proteico , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/patologia , Transdução de Sinais , Fator de Necrose Tumoral alfa/imunologia
20.
J Surg Res ; 194(1): 194-201, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25454973

RESUMO

BACKGROUND: Historically, hilar bile duct resection (HBDR) has been regarded as the choice of treatment for Bismuth types I and II hilar cholangiocarcinoma (HCCA). The present study aimed to evaluate the advantages of major liver resection (MLR) in the treatment of patients with Bismuth types I and II HCCA when compared with HBDR. MATERIALS AND METHODS: Between January 2005 and September 2012, in total, 52 patients with Bismuth types I and II HCCA who underwent HBDR alone or MLR were included for retrospective analysis. The intraoperative outcomes, postoperative complications, and oncological outcomes including recurrence and overall or disease-free survival rate were compared. RESULTS: The MLR group had significantly higher curative resection rates compared with the HBDR group (95% versus 62.5%, P = 0.021) and lower tumor recurrence (28% versus 63%, P = 0.049), albeit with longer operating time (395.5 ± 112.7 versus 270.9 ± 98.8, P < 0.001), and higher blood transfusion requirements (70% versus 16%, P < 0.001). MLR resulted in significantly higher overall postoperative morbidity (70% versus 34.4%, P = 0.012), compared with HBDR alone. When restricted to R0 resections for all the procedures, MLR significantly increased the overall postoperative survival rate compared with the HBDR group (P = 0.016); the overall survival rate at 1, 3 y was 68.4% and 60.8% for MLR group and 59.6% and 21.9% for HBDR group, respectively. Also, the disease-free survival rate was significantly higher in patients who underwent MLR, as compared with those who underwent HBDR (53.2% versus 0% at 3 y, P = 0.005). CONCLUSIONS: Our study has shown that MLR results in higher curative resections, fewer recurrences, and increased postoperative survival rate for Bismuth types I and II HCCA as compared with HBDR alone. However, there is a need for well-designed, multicenter studies to be undertaken to better inform a decision on the standard treatment for Bismuth types I and II HCCA.


Assuntos
Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/cirurgia , Hepatectomia , Idoso , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Taxa de Sobrevida
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