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1.
Micromachines (Basel) ; 15(6)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38930694

RESUMO

In this article, a silicon carbide (SiC) asymmetric MOSFET with a step trench (AST-MOS) is proposed and investigated. The AST-MOS features a step trench with an extra electron current path on one side, thereby increasing the channel density of the device. A thick oxide layer is also employed at the bottom of the step trench, which is used as a new voltage-withstanding region. Furthermore, the ratio of the gate-to-drain capacitance (Cgd) to the gate-to-source capacitance (Cgs) is significantly reduced in the AST-MOS. As a result, the AST-MOS compared with the double-trench MOSFET (DT-MOS) and deep double-trench MOSFET (DDT-MOS), is demonstrated to have an increase of 200 V and 50 V in the breakdown voltage (BV), decreases of 21.8% and 10% in the specific on-resistance (Ron,sp), a reduction of about 1 V in the induced crosstalk voltage, and lower switching loss. Additionally, the trade-off between the resistance of the JFET region (RJFET) and the electric field in the gate oxide (Eox) is studied for a step trench and a deep trench. The improved performances suggest that a step trench is a competitive option in advanced device design.

2.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474286

RESUMO

Glioblastoma multiforme (GBM) is the most common and malignant type of primary brain tumor in adults. Despite important advances in understanding the molecular pathogenesis and biology of this tumor in the past decade, the prognosis for GBM patients remains poor. GBM is characterized by aggressive biological behavior and high degrees of inter-tumor and intra-tumor heterogeneity. Increased understanding of the molecular and cellular heterogeneity of GBM may not only help more accurately define specific subgroups for precise diagnosis but also lay the groundwork for the successful implementation of targeted therapy. Herein, we systematically review the key achievements in the understanding of GBM molecular pathogenesis, mechanisms, and biomarkers in the past decade. We discuss the advances in the molecular pathology of GBM, including genetics, epigenetics, transcriptomics, and signaling pathways. We also review the molecular biomarkers that have potential clinical roles. Finally, new strategies, current challenges, and future directions for discovering new biomarkers and therapeutic targets for GBM will be discussed.

3.
Micromachines (Basel) ; 15(2)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38398982

RESUMO

A SiC double-trench MOSFET embedded with a lower-barrier diode and an L-shaped gate-source in the gate trench, showing improved reverse conduction and an improved switching performance, was proposed and studied with 2-D simulations. Compared with a double-trench MOSFET (DT-MOS) and a DT-MOS with a channel-MOS diode (DTC-MOS), the proposed MOS showed a lower voltage drop (VF) at IS = 100 A/cm2, which can prevent bipolar degradation at the same blocking voltage (BV) and decrease the maximum oxide electric field (Emox). Additionally, the gate-drain capacitance (Cgd) and gate-drain charge (Qgd) of the proposed MOSFET decreased significantly because the source extended to the bottom of the gate, and the overlap between the gate electrode and drain electrode decreased. Although the proposed MOS had a greater Ron,sp than the DT-MOS and DTC-MOS, it had a lower switching loss and greater advantages for high-frequency applications.

4.
Phys Chem Chem Phys ; 25(35): 23746-23752, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37615166

RESUMO

The electronic structure and magnetic properties of Li(ZnMn)As with antisite defects have been investigated by using first-principles calculations within the Perdew-Burke-Ernzerhof generalized gradient approximation. The cation antisite defect induced by Zn substitution for As was considered. Mn-3d, As-4p, Zn-4s, and Zn-4p were involved in the formation of d-sp hybrid orbitals, which enhanced the non-localized properties of Mn-3d electrons and provided a channel of Mn(↑)-As(↓)-ZnAs(↓)-Mn(↑) for indirect exchange of electrons between the magnetic ions. The antisite defect of Zn-substituted As belonged to the acceptor doping, rendering the compound p-type characteristics. The existence of the extra free hole carriers regulated the magnetic ordering transition. The ferromagnetic coupling between the Mn magnetic dopants was more favorable in the system with an antisite defect. In this paper, a novel type of dilute magnetic semiconductor with controllable carriers was designed and the mechanism of ferromagnetic coupling was revealed, which provided a theoretical reference for the subsequent studies.

5.
Nonlinear Dyn ; 111(11): 10677-10692, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152860

RESUMO

In the classical infectious disease compartment model, the parameters are fixed. In reality, the probability of virus transmission in the process of disease transmission depends on the concentration of virus in the environment, and the concentration depends on the proportion of patients in the environment. Therefore, the probability of virus transmission changes with time. Then how to fit the parameters and get the trend of the parameters changing with time is the key to predict the disease course with the model. In this paper, based on the US COVID-19 epidemic statistics during calibration period, the parameters such as infection rate and recovery rate are fitted by using the linear regression algorithm of machine science, and the laws of these parameters changing with time are obtained. Then a SIR model with time delay and vaccination is proposed, and the optimal control strategy of epidemic situation is analyzed by using the optimal control theory and Pontryagin maximum principle, which proves the effectiveness of the control strategy in restraining the transmission of COVID-19. The numerical simulation results show that the time-varying law of the number of active cases obtained by our model basically conforms to the real changing law of the US COVID-19 epidemic statistics during calibration period. In addition, we have predicted the changes in the number of active cases in the COVID-19 epidemic in the USA over time in the future beyond the calibration cycle, and the predicted results are more in line with the actual epidemic data.

6.
Eur Radiol ; 33(4): 2386-2398, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36454259

RESUMO

OBJECTIVES: To predict kidney fibrosis in patients with chronic kidney disease using radiomics of two-dimensional ultrasound (B-mode) and Sound Touch Elastography (STE) images in combination with clinical features. METHODS: The Mindray Resona 7 ultrasonic diagnostic apparatus with SC5-1U convex array probe (bandwidth frequency of 1-5 MHz) was used to perform two-dimensional ultrasound and STE software. The severity of cortical tubulointerstitial fibrosis was divided into three grades: mild interstitial fibrosis and tubular atrophy (IFTA), fibrotic area < 25%; moderate IFTA, fibrotic area 26-50%; and severe IFTA, fibrotic area > 50%. After extracting radiomics from B-mode and STE images in these patients, we analyzed two classification schemes: mild versus moderate-to-severe IFTA, and mild-to-moderate versus severe IFTA. A nomogram was constructed based on multiple logistic regression analyses, combining clinical and radiomics. The performance of the nomogram for differentiation was evaluated using receiver operating characteristic (ROC), calibration, and decision curves. RESULTS: A total of 150 patients undergoing kidney biopsy were enrolled (mild IFTA: n = 74; moderate IFTA: n = 33; severe IFTA: n = 43) and randomized into training (n = 105) and validation cohorts (n = 45). To differentiate between mild and moderate-to-severe IFTA, a nomogram incorporating STE radiomics, albumin, and estimated glomerular filtration (eGFR) rate achieved an area under the ROC curve (AUC) of 0.91 (95% confidence interval [CI]: 0.85-0.97) and 0.85 (95% CI: 0.77-0.98) in the training and validation cohorts, respectively. Between mild-to-moderate and severe IFTA, the nomogram incorporating B-mode and STE radiomics features, age, and eGFR achieved an AUC of 0.93 (95% CI: 0.89-0.98) and 0.83 (95% CI: 0.70-0.95) in the training and validation cohorts, respectively. Finally, we performed a decision curve analysis and found that the nomogram using both radiomics and clinical features exhibited better predictability than any other model (DeLong test, p < 0.05 for the training and validation cohorts). CONCLUSION: A nomogram based on two-dimensional ultrasound and STE radiomics and clinical features served as a non-invasive tool capable of differentiating kidney fibrosis of different severities. KEY POINTS: • Radiomics calculated based on the ultrasound imaging may be used to predict the severities of kidney fibrosis. • Radiomics may be used to identify clinical features associated with the progression of tubulointerstitial fibrosis in patients with CKD. • Non-invasive ultrasound imaging-based radiomics method with accuracy aids in detecting renal fibrosis with different IFTA severities.


Assuntos
Técnicas de Imagem por Elasticidade , Insuficiência Renal Crônica , Humanos , Ultrassonografia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/diagnóstico por imagem , Calibragem , Nomogramas , Fibrose , Estudos Retrospectivos
7.
Langmuir ; 38(33): 10192-10201, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35959936

RESUMO

For vapor condensation, the control of heterogeneous nucleation and spatial distribution of nuclei are crucial for regulating droplet dynamics and improving condensation efficiency. However, due to the complex characteristics of multicomponent, multiphase, and multiscale, the underlying mechanism of mixed vapor condensation remains unclear, especially at the nucleation stage. In this paper, we focus on the enrichment effects of non-uniform wettability surfaces by molecular dynamics simulation, which could intensify the droplet nucleation and growth processes in a water-air mixed system. The results clarify the inhibitory effect of non-condensable gas on droplet nucleation and prove that only 1% of non-condensable gas could reduce one half of the condensation performance from a molecular perspective. Furthermore, non-uniform surfaces are designed to promote the efficient enrichment of vapor molecules on nucleation sites, and the synergistic effect of hydrophilic and hydrophobic regions is proposed. In addition, the non-uniform wettability surfaces are characterized by varying the proportion and dispersion of hydrophilic regions. The results reveal that an optimal proportion of hydrophilic region (R = 5/6) could furnish the non-uniform surface with the best transfer performance. Moreover, the enhancement of condensation performance can also be achieved through the dispersed arrangement of hydrophilic regions. The results provide guidance for the optimized design of functionalized surfaces with enhanced mixed vapor condensation.

8.
Int Heart J ; 63(3): 591-601, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35650159

RESUMO

Circular RNAs (circRNAs) act as important regulators in myocardial infarction (MI). This study aimed to explore the regulatory mechanism of circRNA solute carrier family 8 member A1 antisense RNA 1 (circSLC8A1) in hypoxia-induced myocardial injury.Exosomes were isolated by ultracentrifugation and identified by microscopic observation or protein detection. Protein levels were examined by Western blot. CircSLC8A1, microRNA-214-5p (miR-214-5p), and TEA domain transcription factor 1 (TEAD1) levels were determined via quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability and apoptosis were analyzed by 3-(4,5-dimethylthiazol-2-y1)-2,5-diphenyl tetrazolium bromide (MTT) and flow cytometry, respectively. Inflammatory cytokines were measured using enzyme-linked immunosorbent assay (ELISA). Oxidative stress was assessed by reactive oxygen species (ROS) production, malondialdehyde (MDA) level, and superoxide dismutase (SOD) activity through the corresponding detection kits. Target analysis was performed by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay, and pull-down assay.Exosomes released circSLC8A1 from hypoxic cardiomyocytes. Exosomal circSLC8A1 exacerbated hypoxia-induced repression of cell viability but promotion of cell apoptosis, inflammation, and oxidative stress. Knockdown of circSLC8A1 ameliorated hypoxia-mediated cell injury. CircSLC8A1 directly targeted miR-214-5p and miR-214-5p downregulation reverted the effects of si-circSLC8A1 on hypoxia-treated cardiomyocytes. TEAD1 was a target of miR-214-5p and circSLC8A1 upregulated TEAD1 level via targeting miR-214-5p. In addition, miR-214-5p inhibited hypoxia-caused cell injury by downregulating the expression of TEAD1.These results suggested that circSLC8A1 aggravated cell damages in hypoxia-treated cardiomyocytes by the regulation of TEAD1 via sponging miR-214-5p.


Assuntos
MicroRNAs , Miócitos Cardíacos , RNA Circular , Fatores de Transcrição de Domínio TEA , Hipóxia Celular , Regulação para Baixo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Miócitos Cardíacos/patologia , RNA Circular/genética , Trocador de Sódio e Cálcio , Fatores de Transcrição de Domínio TEA/genética
9.
ACS Omega ; 6(43): 28912-28922, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34746583

RESUMO

In the process of industrial crystallization, it is always difficult to balance the secondary nucleation rate and metastable zone width (MSZW). Herein, we report an experimental and numerical study for the cooling crystallization of paracetamol in an oscillatory flow crystallizer (OFC), finding the optimal operating conditions for balancing the secondary nucleation rate and MSZW. The results show that the MSZW decreases with the increase of oscillation Reynolds number (Re o). Compared to the traditional stirring system, the OFC has an MSZW three times larger than that of the stirring system under a similar power density of consumption. With the numerical simulation, the OFC can produce a stable space environment and instantaneous strong disturbance, which is conducive to the crystallization process. Above all, a high Re o is favorable to produce a sufficient nucleation rate, which may inevitably constrict the MSZW to a certain degree. Then, the optimization strategy of the operating parameter (Re o) in the OFC is proposed.

10.
Nano Lett ; 21(17): 7411-7418, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34176267

RESUMO

Water collection by dew condensation emerges as a sustainable solution to water scarcity. However, the transient condensation process that involves droplet nucleation, growth, and transport imposes conflicting requirements on surface properties. It is challenging to satisfy all benefits for different condensation stages simultaneously. By mimicking the structures and functions of moss Rhacocarpus, here, we report the attainment of dropwise condensation for efficient water collection even on a hydrophilic surface gated by a liquid suction mechanism. The Rhacocarpus-inspired porous surface (RIPS), which possesses a three-level wettability gradient, facilitates a rapid, directional, and persistent droplet suction. Such suction condensation enables a low nucleation barrier, frequent surface refreshing, and well-defined maximum droplet shedding radius simultaneously. Thus, a maximum ∼160% enhancement in water collection performance compared to the hydrophobic surface is achieved. Our work provides new insights and a design route for developing engineered materials for a wide range of water-harvesting and phase-change heat-transfer applications.


Assuntos
Água , Interações Hidrofóbicas e Hidrofílicas , Sucção , Propriedades de Superfície , Molhabilidade
11.
Pancreatology ; 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33933371

RESUMO

PURPOSE: The purpose of the multi-institutional retrospective study was to evaluate whether intraoperative radiotherapy (IORT) has advantages in the treatment of patients with locally advanced pancreatic cancer (LAPC) compared with concurrent chemoradiotherapy (CCRT). PATIENTS AND METHODS: A total of 103 patients with LAPC whom was treated with IORT (Arm A; n = 50) or CCRT (Arm B; n = 53) from 2015.6 to 2016.7 were retrospectively identified. Data on feasibility, toxicity, and overall survival (OS) were evaluated. RESULTS: Most factors of the two cohorts were similar. The severe adverse events (grade 3 and 4) patients in Arm B were higher than patients in Arm A (34% vs 0%). Disease progression was noted in 38 patients (76%) in Arm A and 37 patients (69.8%) in Arm B. The median survival of patients in Arm A and B were 15.3 months (95% CI, 13.0-17.6 months) and 13.8 months (95% CI, 11.0-16.6 months), respectively. The 1-year survival rate were 66.3% in Arm A (95% CI, 52.3%-80.2%) and 60.9% in Arm B (95% CI, 46.4%-75.4%). There was no significant difference in OS between patients treated with IORT and with CCRT (p = 0.458). CONCLUSION: Our results demonstrated that patients with LAPC treated with IORT showed fewer adverse events, less treatment time, and high feasibility compared to CCRT. Although, IORT has no advantages in survival and tumor control compared with CCRT.

12.
Med Ultrason ; 23(1): 29-35, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33621272

RESUMO

AIM: The study retrospectively analysed the accuracy of preoperative contrast-enhanced ultrasound (CEUS) in differenti-ating stage Ta-T1 or low-grade bladder cancer (BC) from stage T2 or high-grade bladder cancer. MATERIAL AND METHODS: We systematically searched the literature indexed in PubMed, Embase, and the Cochrane Library for original diagnostic articles of bladder cancer. The diagnostic accuracy of CEUS was compared with cystoscopy and/or transurethral resection of bladder tumors (TURBT). The bivariate logistic regression model was used for data pooling, couple forest plot, diagnostic odds ratio (DOR) and summary receiver operating characteristic (SROC). RESULTS: Five studies met the selection criteria; the overall number of reported bladder cancers patients were 436. The pooled-sensitivity (P-SEN), pooled-specificity (P-SPE), pooled-positive likelihood ratio (PLR+), pooled-negative likelihood ratio (PLR-), DOR, and area under the SROC curve were 94.0% (95%CI: 85%-98%), 90% (95%CI: 83%-95%), 9.5 (95%CI: 5.1-17.6), 0.06 (95%CI: 0.02-0.17), 147 (95%CI: 35-612) and 97% (95% CI: 95%-98%) respectively. CONCLUSION: CEUS reaches a high efficiency in discriminating Ta-T1 or low-grade bladder cancer from stage T2 or high-grade bladder cancer. It can be a promising method in patients to distinguish T staging and grading of bladder cancer because of its high sensitivity, specificity and diagnostic accuracy.


Assuntos
Neoplasias da Bexiga Urinária , Humanos , Estadiamento de Neoplasias , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia , Neoplasias da Bexiga Urinária/diagnóstico por imagem
13.
Langmuir ; 37(5): 1779-1787, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33502854

RESUMO

The coalescence-induced droplet jumping on superhydrophobic surfaces is fundamentally significant from an academic or practical viewpoint. However, approaches to enhance droplet jumping velocity are very limited. In this work, the effect of structural parameters of the triangular prism on droplet jumping is studied systematically. The results indicate that droplet jumping velocity can be greatly increased by exploiting structure effects, which is a promising reinforcement method. When the height and apex angle of the triangular prism are fixed, the droplet jumping velocity increases with the length of the triangular prism until a plateau is reached. The ratio of translational kinetic energy to released surface energy during droplet jumping is determined by the apex angle and the height of the triangular prism, which is more effective with a smaller apex angle and a larger height. The results are supposed to provide guidelines for optimization of superhydrophobic surfaces.

14.
Langmuir ; 37(2): 774-784, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33382946

RESUMO

Controlling vapor nucleation on micro-/nanostructured surfaces is critical to achieving exciting droplet dynamics and condensation enhancement. However, the underlying mechanism of nucleation phenomena remains unclear because of its nature of nanoscale and transience, especially for the complex-structured surfaces. Manipulating vapor nucleation via the rational surface design of micro-/nanostructures is extremely challenging. Here, we fabricate hierarchical surfaces comprising tapered nanowire bunches and crisscross microgrooves. Nanosteps are formed around the top of the nanowire bunches, where the nanowires all around agglomerate densely because of surface tension. The theoretical analysis and molecular dynamics simulation show that nanostep morphologies that are around the top of the nanowire bunches can enable a lower energy barrier and a higher nucleation capability than those of the sparsely packed nanowires at the center and bottom of the nanowire bunches. Vapor condensation experiments demonstrate that the nucleation preferentially occurs around the top of the nanowire bunches. The results provide guidelines to design micro-/nanostructures for promoting vapor nucleation and droplet removal in condensation.

15.
Langmuir ; 33(25): 6258-6268, 2017 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-28562053

RESUMO

The coalescence-induced droplet jumping on superhydrophobic surfaces (SHSs) has attracted considerable attention over the past several years. Most of the studies on droplet jumping mainly focus on two-droplet coalescence events whereas the coalescence of three or more droplets is actually more frequent and still remains poorly understood. In this work, a 3D lattice Boltzmann simulation is carried out to investigate the effect of initial droplet arrangements on the coalescence-induced jumping of three equally sized droplets. Depending on the initial position of droplets on the surface, the droplet coalescence behaviors can be generally classified into two types: one is that all droplets coalesce together instantaneously (concentrated configuration), and the other is that the initial coalesced droplet sweeps up the third droplet in its moving path (spaced configuration). The critical Ohnesorge number, Oh, for the transition of inertial-capillary-dominated coalescence to inertially limited-viscous coalescence is found to be 0.10 for droplet coalescence on SHSs with a contact angle of 160°. The jumping droplet velocity for concentrated multidroplet coalescence at Oh ⩽ 0.10 still follows the inertial-capillary scaling with an increased prefactor, which indicates a viable jumping droplet velocity enhancement scheme. However, the droplet jumping velocity is drastically reduced for the spaced configuration compared to that for the aforementioned concentrated configuration. Because Oh exceeds 0.10, the effects of initial droplet arrangements on multidroplet jumping become weaker as viscosity plays a key role in the merging process. This work will provide effective guidelines for the design of functional SHSs with enhanced droplet jumping for a wide range of industrial applications.

16.
Sci Rep ; 7(1): 987, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28428638

RESUMO

Condensation is a common physical process which widely exists in natural phenomena and thermal energy systems. In a condensation process, cluster is considered as the important bridge between vapor body and condensates. However, limited by the minimum imaging dimension of traditional measurements, early experimental studies about initial stages of condensation process are not sufficient. This paper provides a powerful optical platform for the study of dynamic clusters process. Based on the Rayleigh law, optical experiments were firstly introduced to investigate the clusters spatial distribution close to and far from condensation surface. The results show that clusters are mainly generated in the vicinity of the condensation surface within the thickness of 200 µm. When they move away from the condensation surface, clusters progressively vanish and they have a life cycle of a fraction of a millisecond. Though scattering intensity is proportional to the 6th power of cluster radius r and cluster number density N c theoretically, the scattering intensity does not increase sharply with the increase of subcooling degree from the experimental results, so we can infer that the cluster number density plays a dominate role in this process and the effect of cluster radius almost can be ignored.Zhong Lan and Di Wang contributed equally to this work.

17.
ACS Appl Mater Interfaces ; 9(15): 13770-13777, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28362085

RESUMO

Nanostructured superhydrophobic surfaces have been actively explored to promote favorable droplet dynamics for a wide range of technological applications. However, the tendency of condensed droplets to form as pinned states greatly limits their applicability in enhancing condensation heat transfer efficiency. Despite recent progresses, the understanding of physical mechanisms governing the wetting transition of condensed droplets is still lacking. In this work, a nanostructured superhydrophobic surface with tapered nanogaps is fabricated to demonstrate the coordination of surface wetting property, topography, and the condensing condition on the wetting state and dynamic behavior of condensed droplets. Combining the environmental scanning electron microscopy and optical visualization methods, we systematically show the morphology of nucleated droplets in nanostructures and the droplet dynamic evolution throughout the growth stages, which provides the direct evidence of condensing condition-induced droplet wetting transition. When the surface subcooling is smaller than 0.3 K, the droplets formed as the Cassie-Baxter state, followed by coalescence-induced droplet jumping. With the increase of surface subcooling up to 0.6 K, however, droplet formation occurs randomly inside nanogaps, resulting in the loss of superhydrophobicity. These new observations along with the new insights about the coordination of surface properties and condensing conditions on droplet wetting transition are useful for guiding the development of novel surfaces for improving droplet removal and phase-change heat transfer.

18.
Sci Rep ; 6: 18836, 2016 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-26743167

RESUMO

The behavior of droplets trapped in geometric structures is essential to droplet manipulation applications such as for droplet transport. Here we show that directional droplet movement can be realized by a V-shaped groove with the movement direction controlled by adjusting the surface wettability of the groove inner wall and the cross sectional angle of the groove. Experiments and analyses show that a droplet in a superhydrophobic groove translates from the immersed state to the suspended state as the cross sectional angle of the groove decreases and the suspended droplet departs from the groove bottom as the droplet volume increases. We also demonstrate that this simple grooved structure can be used to separate a water-oil mixture and generate droplets with the desired sizes. The structural effect actuated droplet movements provide a controllable droplet transport method which can be used in a wide range of droplet manipulation applications.

19.
World J Gastroenterol ; 21(24): 7604-7, 2015 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-26140011

RESUMO

Pancreatic tumors, with peri-pancreatic main vascular invasion, especially the superior mesenteric vein (SMV) or the portal vein, are very common. In some cases, vascular resection and reconstruction are required for complete resection of pancreatic tumors. However, the optimum surgical method for venous management is controversial. Resection of the SMV without reconstruction during surgery for pancreatic tumors is rarely reported. Here we present the case of a 58-year-old woman with a giant pancreatic mucinous cystadenoma adhering to the SMV, who underwent an en bloc tumor resection, including the main trunk of the SMV and the spleen. No venous reconstruction was performed during surgery. No ischemic changes occurred in the bowel. The presence of several well-developed collateral vessels was shown by 3-dimensional computed tomography examination. The patient had an uneventful postoperative period and was discharged. This case indicated that the main trunk of the SMV can be resected without venous reconstruction if adequate collateralization has formed.


Assuntos
Cistadenoma Mucinoso/cirurgia , Veias Mesentéricas/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Carga Tumoral , Circulação Colateral , Cistadenoma Mucinoso/patologia , Feminino , Humanos , Veias Mesentéricas/diagnóstico por imagem , Veias Mesentéricas/patologia , Veias Mesentéricas/fisiopatologia , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Pancreáticas/patologia , Circulação Esplâncnica , Esplenectomia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
20.
World J Gastroenterol ; 21(14): 4255-60, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25892876

RESUMO

AIM: To investigate the prognostic value of metastatic lymph node ratio (MLNR) in extrahepatic cholangiocarcinoma (ECC) patients undergoing radical resection. METHODS: Seventy-eight patients with ECC were enrolled. Associations between various clinicopathologic factors and prognosis were investigated by Kaplan-Meier analyses. The Cox proportional-hazards model was used for multivariate survival analysis. RESULTS: The overall three- and five-year survival rates were 47.26% and 23.99%, respectively. MLNR of 0, 0-0.2, 0.2-0.5, and > 0.5 corresponded to five-year survival rates of 28.59%, 21.60%, 18.84%, and 10.03%, respectively. Univariate analysis showed that degree of tumor differentiation, lymph node metastasis, MLNR, tumor-node-metastasis (TNM) stage, and margin status were closely associated with postoperative survival in ECC patients (P < 0.05). Multivariate analysis showed that MLNR and TNM stage were independent prognostic factors after pancreaticoduodenectomy (HR = 2.13, 95%CI: 1.45-3.11; P < 0.01; and HR = 1.97, 95%CI: 1.17-3.31; P = 0.01, respectively). The median survival time for MLNR > 0.5, 0.2-0.5, 0-0.2, and 0 was 15 mo, 24 mo, 23 mo, and 35.5 mo, respectively. There were statistical differences in survival time between patients with different MLNR (χ(2) = 15.38; P < 0.01). CONCLUSION: MLNR is an independent prognostic factor for ECC patients after radical resection and is useful for predicting postoperative survival.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/secundário , Linfonodos/patologia , Adulto , Idoso , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/cirurgia , Diferenciação Celular , Distribuição de Qui-Quadrado , Colangiocarcinoma/mortalidade , Colangiocarcinoma/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Excisão de Linfonodo , Linfonodos/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Pancreaticoduodenectomia , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
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