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1.
Proc Natl Acad Sci U S A ; 118(8)2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33602823

RESUMO

Many cancers evade immune rejection by suppressing major histocompatibility class I (MHC-I) antigen processing and presentation (AgPP). Such cancers do not respond to immune checkpoint inhibitor therapies (ICIT) such as PD-1/PD-L1 [PD-(L)1] blockade. Certain chemotherapeutic drugs augment tumor control by PD-(L)1 inhibitors through potentiation of T-cell priming but whether and how chemotherapy enhances MHC-I-dependent cancer cell recognition by cytotoxic T cells (CTLs) is not entirely clear. We now show that the lysine acetyl transferases p300/CREB binding protein (CBP) control MHC-I AgPPM expression and neoantigen amounts in human cancers. Moreover, we found that two distinct DNA damaging drugs, the platinoid oxaliplatin and the topoisomerase inhibitor mitoxantrone, strongly up-regulate MHC-I AgPP in a manner dependent on activation of nuclear factor kappa B (NF-κB), p300/CBP, and other transcription factors, but independently of autocrine IFNγ signaling. Accordingly, NF-κB and p300 ablations prevent chemotherapy-induced MHC-I AgPP and abrogate rejection of low MHC-I-expressing tumors by reinvigorated CD8+ CTLs. Drugs like oxaliplatin and mitoxantrone may be used to overcome resistance to PD-(L)1 inhibitors in tumors that had "epigenetically down-regulated," but had not permanently lost MHC-I AgPP activity.

2.
Sensors (Basel) ; 20(23)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266108

RESUMO

In visual tracking, the tracking model must be updated online, which often leads to undesired inclusion of corrupted training samples, and hence inducing tracking failure. We present a locality preserving correlation filter (LPCF) integrating a novel and generic decontamination approach, which mitigates the model drift problem. Our decontamination approach maintains the local neighborhood feature points structures of the bounding box center. This proposed tracking-result validation approach models not only the spatial neighborhood relationship but also the topological structures of the bounding box center. Additionally, a closed-form solution to our approach is derived, which makes the tracking-result validation process could be accomplished in only milliseconds. Moreover, a dimensionality reduction strategy is introduced to improve the real-time performance of our translation estimation component. Comprehensive experiments are performed on OTB-2015, LASOT, TrackingNet. The experimental results show that our decontamination approach remarkably improves the overall performance by 6.2%, 12.6%, and 3%, meanwhile, our complete algorithm improves the baseline by 27.8%, 34.8%, and 15%. Finally, our tracker achieves the best performance among most existing decontamination trackers under the real-time requirement.

3.
Opt Express ; 28(21): 30675-30685, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33115063

RESUMO

We propose a switchable broadband and wide-angular terahertz asymmetric transmission based on a spiral metasurface composed of metal and VO2 hybrid structures. Results show that asymmetric transmission reaching up to 15% can be switched on or off for circularly polarized terahertz waves when the phase of VO2 transits from the insulting state to the conducting state or reversely. Strikingly, we find that relatively high asymmetric transmission above 10% can be maintained over a broad bandwidth of 2.6-4.0 THz and also over a large incident angular range of 0°-45°. We further discover that as the incident angle increases, the dominant chirality of the proposed metasurface with VO2 in the conducting state can shift from intrinsic to extrinsic chirality. We expect this work will advance the engineering of switchable chiral metasurfaces and promote terahertz applications.

4.
Phys Chem Chem Phys ; 22(37): 21428-21435, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32944724

RESUMO

Tunable optical properties play an important role in the high performance of optoelectronic applications based on two-dimensional (2D) transition metal carbide and nitride (MXene) materials. Herein, the optical properties of functionalized MXene monolayers Sc2CT2 (T = O and OH) are investigated by strain engineering. The strain-dependent linear optical properties of Sc2CT2 possess broadband optical response due to the geometry and orbital overlap effect. The peaks from the second-order nonlinear coefficient elements d (d15, d16, and d31) at around half the band-gap exhibit a redshift for Sc2CO2 (blueshift for Sc2C(OH)2) with the increase of strain. The strain-dependent d reveals that Sc2CO2 with -1268 pm V-1 %-1 has a larger photoelastic coefficient than that of Sc2C(OH)2 with -574 pm V-1 %-1 at 1% strain. Meanwhile, the photoelastic tensors can not only be increased but also reduced with the increase of strain due to the dispersion relation. Moreover, the azimuthal angle-dependent second harmonic generation (SHG) from strained Sc2CT2 monolayers depends highly on the strained states and the pumping photon energy. The results pave the way for the tunable, broadband, and anisotropic applications of nonlinear optoelectronic devices based on MXenes based on strain engineering.

5.
ACS Appl Mater Interfaces ; 12(42): 48161-48169, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-32990422

RESUMO

The surface-charge region of bulk and monolayer MoSe2 is analyzed directly by terahertz (THz) surface emission spectroscopy in a nondestructive way. Both surface nonlinear optical polarization and surface field-induced photocurrent contribute to the THz radiation in both bulk and monolayer MoSe2. The first THz emission mechanism is due to the surface optical rectification and the second one is due to the photogenerated carriers accelerated by the surface depletion field. The THz radiation contribution from the surface optical rectification is basically the same for both bulk and monolayer MoSe2 because of the same symmetry at the surface. However, the contribution from the surface field-induced photocurrent is ∼94.2% in bulk MoSe2 and it goes down to 74.5% in monolayer MoSe2. This is due to the larger surface depletion field in bulk MoSe2 (∼2.54 × 107 V/m) compared with that in monolayer MoSe2 (∼5.42 × 105 V/m), as such THz emission from the bulk is approximately four times larger than that from monolayer MoSe2. This work not only proves the clear THz radiation mechanism from MoSe2 crystals but also affords a THz technology for the surface characterization of two-dimensional materials.

6.
Nat Biomed Eng ; 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958897

RESUMO

The clinical applicability of porcine xenotransplantation-a long-investigated alternative to the scarce availability of human organs for patients with organ failure-is limited by molecular incompatibilities between the immune systems of pigs and humans as well as by the risk of transmitting porcine endogenous retroviruses (PERVs). We recently showed the production of pigs with genomically inactivated PERVs. Here, using a combination of CRISPR-Cas9 and transposon technologies, we show that pigs with all PERVs inactivated can also be genetically engineered to eliminate three xenoantigens and to express nine human transgenes that enhance the pigs' immunological compatibility and blood-coagulation compatibility with humans. The engineered pigs exhibit normal physiology, fertility and germline transmission of the 13 genes and 42 alleles edited. Using in vitro assays, we show that cells from the engineered pigs are resistant to human humoral rejection, cell-mediated damage and pathogenesis associated with dysregulated coagulation. The extensive genome engineering of pigs for greater compatibility with the human immune system may eventually enable safe and effective porcine xenotransplantation.

7.
Cancer Lett ; 492: 185-196, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32758616

RESUMO

Breast cancer is the most common cancer among women worldwide, with 70% being estrogen receptor-positive (ER+). Although ER-targeted treatment is effective in treating ER + breast cancer, chemoresistance and metastasis still prevail. Outcome-predictable biomarkers can help improve patient prognosis. Through the analysis of the Array Express database, The Cancer Genome Atlas-Breast Cancer datasets, and breast tumor tissue array results, we found that cytochrome c oxidase subunit 5a (COX5A) was related to poor prognosis of ER + breast cancer. Further studies revealed that COX5A was positively associated with metastasis and chemoresistance in ER + breast cancer. In vitro experiments showed that knockdown of COX5A was accompanied by a decrease in ERα expression, cell cycle arrest, and epithelial-mesenchymal transition blockade, resulting in an inhibition of proliferation and invasion. Knockdown of COX5A enhanced the chemosensitivity of breast cancer cells by decreasing adenosine triphosphate and increasing reactive oxygen species levels. We report that miR-204 can target and inhibit the expression of COX5A, thus, reversing the functions of COX5A in ER + breast cancer cells. We found that COX5A may serve as a prognostic biomarker in ER + breast cancer.

8.
Cureus ; 12(6): e8925, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32642389

RESUMO

To date, the etiology of preeclampsia (PE) has not been clarified and the specific treatment is lacking; hence, early prediction and prevention are very important. Thus, a large number of biomarkers that may be associated with PE have been identified based on proteomics to provide a reference for the prediction of PE and for the understanding of the pathological mechanisms of this disease. This article briefly summarizes the application of proteomics in PE and the potential protein biomarkers to provide a reference for other researchers.

9.
Adv Healthc Mater ; 9(16): e2000536, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32597571

RESUMO

Targeting areas of inflammation offers potential therapeutic and diagnostic benefits by maximizing drug and imaging marker on-target effects while minimizing systemic exposure that can be associated with adverse side effects. This strategy is particularly beneficial in the management of inflammatory bowel disease (IBD). Here an inflammation-targeting (IT) approach based on heparin-coated human serum albumin nanoparticles (HEP-HSA NPs) that utilize the increased intestinal permeability and changes in electrostatic interaction at the site of intestinal inflammation is described. Using small-molecule and biologic drugs as a model for drug combination, the HEP-HSA NPs demonstrate the capacity to load both drugs simultaneously; the dual-drug loaded HEP-HSA NPs exhibit a higher anti-inflammatory effect than both of the single-drug loaded NPs in vitro and selectively bind to inflamed intestine after enema administration in vivo in a murine model of colitis. Importantly, analyses of the physicochemical characteristics and targeting capacities of these NPs indicate that HEP coating modulates NP binding to the inflamed intestine, providing a foundation for future IT-NP formulation development.

10.
Int J Mol Sci ; 21(10)2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32429319

RESUMO

Sugar allocation is based on the source-to-sink and intracellular transport between different organelles, and sugar transporters are usually involved in these processes. Tonoplast sugar transporters (TST) are responsible for transporting sugar into vacuoles; however, the role of TSTs in root growth and the response to abiotic stress is poorly studied. Here, RNA analysis and promoter-ß-glucuronidase staining revealed that a melon TST1 gene (CmTST1) is highly expressed in the roots. The sugar feeding experiment results showed that the expression of CmTST1 in the roots was induced by a relatively high level of sucrose (6%), glucose (3%), and fructose (3%). The ectopic overexpression of CmTST1 in Arabidopsis improved the root and shoot growth of seedlings under high exogenous sugar stress. Furthermore, the ectopic expression of CmTST1 promoted the expression of plasma membrane-located sugar transporters. We proposed that CmTST1 plays a key role in importing sugar transport into the vacuoles of roots in response to metabolic demands to maintain cytosolic sugar homeostasis.

11.
Appl Opt ; 59(12): 3686-3691, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32400491

RESUMO

Chirality has received wide attention due to its promising applications in biopharmaceuticals, chemical detection, and polarized optoelectronic devices. Herein, metamaterials with layered Tai Chi patterns are proposed to get strong and tunable chirality. Based on the surface current distribution analysis, a coupling model considering both the magnetic and electric dipoles in the upper and bottom metallic structures is proposed to understand the circular dichroism. Accordingly, both an external chiral modulation by changing the incident angle and an internal chiral modulation by changing the twist angle are achieved. Incident-angle-dependent circular dichroism modulation exhibits a range of 0.44-0.62 and the twist-angle-dependent modulation range is ${-}{0.6 - 0.42}$-0.6-0.42, where the negative value means the polarity of the circular dichroism can also be tuned. This work deepens the understanding of angular-dependent chirality in metamaterials and expands the potential for terahertz polarization optoelectronic applications.

12.
Lab Invest ; 100(8): 1030-1041, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32238906

RESUMO

Talin and vinculin, both actin-cytoskeleton-related proteins, have been documented to participate in establishing bacterial infections, respectively, as the adapter protein to mediate cytoskeleton-driven dynamics of the plasma membrane. However, little is known regarding the potential role of the talin-vinculin complex during spotted fever group rickettsial and Ebola virus infections, two dreadful infectious diseases in humans. Many functional properties of proteins are determined by their participation in protein-protein complexes, in a temporal and/or spatial manner. To resolve the limitation of application in using mouse primary antibodies on archival, multiple formalin-fixed mouse tissue samples, which were collected from experiments requiring high biocontainment, we developed a practical strategic proximity ligation assay (PLA) capable of employing one primary antibody raised in mouse to probe talin-vinculin spatial proximal complex in mouse tissue. We observed an increase of talin-vinculin spatial proximities in the livers of spotted fever Rickettsia australis or Ebola virus-infected mice when compared with mock mice. Furthermore, using EPAC1-knockout mice, we found that deletion of EPAC1 could suppress the formation of spatial proximal complex of talin-vinculin in rickettsial infections. In addition, we observed increased colocalization between spatial proximity of talin-vinculin and filamentous actin-specific phalloidin staining in single survival mouse from an ordinarily lethal dose of rickettsial or Ebola virus infection. These findings may help to delineate a fresh insight into the mechanisms underlying liver specific pathogenesis during infection with spotted fever rickettsia or Ebola virus in the mouse model.


Assuntos
Citoesqueleto de Actina/metabolismo , Membrana Celular/metabolismo , Doença pelo Vírus Ebola/metabolismo , Fígado/metabolismo , Talina/metabolismo , Vinculina/metabolismo , Animais , Células Cultivadas , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Fígado/microbiologia , Fígado/virologia , Camundongos Knockout , Ligação Proteica , Rickettsia/fisiologia , Rickettsiose do Grupo da Febre Maculosa/metabolismo , Rickettsiose do Grupo da Febre Maculosa/microbiologia , Talina/química , Vinculina/química
13.
Phys Chem Chem Phys ; 22(7): 3849-3854, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32022047

RESUMO

Zeolitic imidazolate frameworks (ZIFs) represent a novel class of porous crystalline materials that have demonstrated potential as light harvesting materials for solar energy conversion. In order to facilitate their application in solar energy conversion, it is necessary to expand their absorption further into the realm of the solar spectrum. In this work, we report the incorporation of semiconductor cadmium sulfide nanowires (CdS NWs) into ZIF-67 (CdS@ZIF-67), where a broader region of the solar spectrum can be absorbed by CdS NWs and relayed to ZIF-67 through an energy transfer (EnT) process. Using steady-state emission and time resolved emission and absorption spectroscopy, we show that efficient EnT can occur from CdS NWs to ZIF-67 by selective excitation of CdS NWs. The EnT time is ∼729.9 ps, which corresponds to 71.2% EnT efficiency.

14.
J Vis Exp ; (151)2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31545316

RESUMO

This article presents a general experimental protocol for programmable one-pot oligosaccharide synthesis and demonstrates how to use Auto-CHO software for generating potential synthetic solutions. The programmable one-pot oligosaccharide synthesis approach is designed to empower fast oligosaccharide synthesis of large amounts using thioglycoside building blocks (BBLs) with the appropriate sequential order of relative reactivity values (RRVs). Auto-CHO is a cross-platform software with a graphical user interface that provides possible synthetic solutions for programmable one-pot oligosaccharide synthesis by searching a BBL library (containing about 150 validated and >50,000 virtual BBLs) with accurately predicted RRVs by support vector regression. The algorithm for hierarchical one-pot synthesis has been implemented in Auto-CHO and uses fragments generated by one-pot reactions as new BBLs. In addition, Auto-CHO allows users to give feedback for virtual BBLs to keep valuable ones for further use. One-pot synthesis of stage-specific embryonic antigen 4 (SSEA-4), which is a pluripotent human embryonic stem cell marker, is demonstrated in this work.


Assuntos
Oligossacarídeos/síntese química , Antígenos Embrionários Estágio-Específicos/química , Glicosilação , Humanos , Software
15.
Lab Invest ; 99(11): 1650-1660, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31253864

RESUMO

Understanding bacterial adhesion is challenging and critical to our understanding of the initial stages of the pathogenesis of endovascular bacterial infections. The vascular endothelial cell (EC) is the main target of Rickettsia, an obligately intracellular bacterium that causes serious systemic disease in humans and animals. But the mechanism(s) underlying bacterial adherence to ECs under shear stress from flowing blood prior to activation are unknown for any bacteria. Although host surface annexin a2 (ANXA2) has been identified to participate in efficient bacterial invasion of epithelial cells, direct evidence is lacking in the field of bacterial infections of ECs. In the present study, we employ a novel, anatomically based, in vivo quantitative bacterial-adhesion-to-vascular-EC system, combined with atomic force microscopy (AFM), to examine the role of endothelial luminal surface ANXA2 during rickettsial adherence to ECs. We also examined whether ANXA2 antibody affected binding of Staphylococcus aureus to ECs. We found that deletion of ANXA2 impeded rickettsial attachment to the ECs in vitro and blocked rickettsial adherence to the blood vessel luminal surface in vivo. The AFM studies established that EC surface ANXA2 acts as an adherence receptor for rickettsiae, and that rickettsial adhesin OmpB is the associated bacterial ligand. Furthermore, pretreatment of ECs with anti-ANXA2 antibody reduced EC surface-associated S. aureus. We conclude that the endothelial surface ANXA2 plays an important role in initiating pathogen-host interactions, ultimately leading to bacterial anchoring on the vascular luminal surface.


Assuntos
Anexina A2/fisiologia , Aderência Bacteriana/fisiologia , Células Endoteliais/microbiologia , Células Endoteliais/fisiologia , Animais , Anexina A2/deficiência , Anexina A2/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/fisiologia , Fenômenos Biomecânicos , Modelos Animais de Doenças , Interações entre Hospedeiro e Microrganismos/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia de Força Atômica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Rickettsia/patogenicidade , Rickettsia/fisiologia , Infecções por Rickettsia/microbiologia , Staphylococcus aureus/patogenicidade , Staphylococcus aureus/fisiologia
16.
BMJ Open ; 9(4): e026527, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015272

RESUMO

OBJECTIVES: Our aim was to assess the release level of heparin-binding protein (HBP) in sepsis and septic shock under the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). DESIGN: Prospective cohort study. SETTING: A general teaching hospital in China. PARTICIPANTS: Adult infected patients with suspected sepsis and people who underwent physical examination were included. According to the health status and severity of illness, the research subjects were divided into healthy, local infection, sepsis non-shock and septic shock under Sepsis-3 definitions. MAIN OUTCOME MEASURES: Plasma levels of HBP, procalcitonin (PCT), C reactive protein (CRP) and complete blood count were detected in all subjects. Single-factor analysis of variance was used to compare the biomarker levels of multiple groups. A receiver operating characteristic (ROC) curve was used to assess the diagnostic capacity of each marker. RESULTS: HBP levels were significantly higher in patients with sepsis non-shock than in those with local infections (median 49.7ng/mL vs 11.8 ng/mL, p<0.01) at enrolment. Moreover, HBP levels in patients with septic shock were significantly higher than in patients with sepsis without shock (median 153.8ng/mL vs 49.7 ng/mL, p<0.01). The area under the ROC curve (AUC) of HBP (cut-off ≥28.1 ng/mL) was 0.893 for sepsis which was higher than those of PCT (0.856) for a cut-off ≥2.05 ng/mL and of CRP (0.699) for a cut-off ≥151.9 mg/L. Moreover, AUC of HBP (cut-off ≥103.5 ng/mL) was 0.760 for septic shock which was higher than the ROC curve of sequential [sepsis-related] organ failure assessment (SOFA) Score (0.656) for a cut-off ≥5.5. However, there was no significant difference between 28-d survivors (n=56) and 28-d non-survivors (n=37) with sepsis in terms of HBP value (p=0.182). CONCLUSIONS: A high level of HBP in plasma is associated with sepsis, which might be a useful diagnostic marker in patients with suspected sepsis.


Assuntos
Peptídeos Catiônicos Antimicrobianos/sangue , Proteína C-Reativa/análise , Pró-Calcitonina/sangue , Sepse/sangue , Sepse/diagnóstico , Choque Séptico/sangue , Choque Séptico/diagnóstico , Idoso , Proteínas Sanguíneas , China , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
17.
Mol Microbiol ; 111(6): 1529-1543, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30838726

RESUMO

Bacterial antibiotic resistance, a global health threat, is caused by plasmid transfer or genetic mutations. Quinolones are important antibiotics, partially because they are fully synthetic and resistance genes are unlikely to exist in nature; nonetheless, quinolone resistance proteins have been identified. The mechanism by which plasmid-borne quinolone resistance proteins promotes the selection of quinolone-resistant mutants is unclear. Here, we show that QnrB increases the bacterial mutation rate. Transcriptomic and genome sequencing analyses showed that QnrB promoted gene abundance near the origin of replication (oriC). In addition, the QnrB expression level correlated with the replication origin to terminus (oriC/ter) ratio, indicating QnrB-induced DNA replication stress. Our results also show that QnrB is a DnaA-binding protein that may act as an activator of DNA replication initiation. Interaction of QnrB with DnaA promoted the formation of the DnaA-oriC open complex, which leads to DNA replication over-initiation. Our data indicate that plasmid-borne QnrB increases bacterial mutation rates and that genetic changes can alleviate the fitness cost imposed by transmitted plasmids. Derivative mutations may impair antibiotic efficacy and threaten the value of antibiotic treatments. Enhanced understanding of how bacteria adapt to the antibiotic environment will lead to new therapeutic strategies for antibiotic-resistant infections.


Assuntos
Replicação do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Taxa de Mutação , DNA Bacteriano/metabolismo , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Perfilação da Expressão Gênica , Aptidão Genética , Mutação , Plasmídeos/genética , Quinolonas/farmacologia , Origem de Replicação , Sequenciamento Completo do Genoma
18.
Life Sci ; 221: 1-12, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30738042

RESUMO

Plasmin-mediated fibrinolysis at the surface of vascular endothelial cells (SVEC) plays a key role in maintaining vascular hemostasis, in which the cAMP pathway participates. After externalization to the SVEC, annexin A2 (ANXA2) serves as a platform for conversion of plasminogen to plasmin. Here we describe a regulatory role of the exchange protein directly activated by cAMP (EPAC) in ANXA2 externalization and vascular fibrinolysis. Knockout of EPAC1 in mice results in a decreased ANXA2 expression on the SVEC associated with increased fibrin deposition and fibrinolytic dysfunction. Reduced levels of EPAC1 are also found in endocardial tissues beneath atrial mural thrombi in patients. Notably, administration of recombinant ANXA2 ameliorates fibrinolytic dysfunction in the EPAC1-null mice. Mechanistically, EPAC1 regulates the SVEC plasminogen conversion depended on ANXA2. EPAC1 promotes tyrosine-23 phosphorylation of ANXA2, a prerequisite for its recruitment to the SVEC. Our data thus reveal a novel regulatory role for EPAC1 in vascular fibrinolysis.


Assuntos
Anexina A2/metabolismo , Fibrinólise/fisiologia , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Animais , Membrana Celular , AMP Cíclico/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/fisiologia , Endotélio Vascular , Fibrinolisina/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Homeostase , Humanos , Camundongos , Camundongos Knockout , Fosforilação , Plasminogênio/metabolismo , Proteólise
19.
Nanotechnology ; 30(19): 195705, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30699402

RESUMO

Broadband terahertz (THz) impedance matching is important for both spectral resolution improvement and THz anti-radar technology. Herein, graphene-silicon hybrid structure has been proposed for active broadband THz wave impedance matching with optical tunability. The main transmission pulse measured in the time domain indicates a modulation depth as high as 92.7% totally from the graphene-silicon interface. The interface reflection from the graphene-silicon junction implies that an impedance matching condition can be actively achieved by optical doping. To reveal the mechanism, we propose a graphene-silicon heterojunction model, which gives a full consideration of both the THz conductivity of graphene and the loss in doped junction layer. The theory fits well with the experimental results. This work proves active THz wave manipulation by junction effect and paves the way for active anti-reflection coating for THz components.

20.
Am Surg ; 85(12): 1376-1380, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31908221

RESUMO

Clinically relevant pancreatic fistula (CR-POPF), after distal pancreatectomy (DP), remains a clinical challenge. Prior studies investigating the relationship between BMI and CR-POPF have yielded conflicting results. We hypothesized that BMI is associated with CR-POPF in patients having DP for pancreatic ductal adenocarcinoma (PDAC). Patients who underwent DP for PDAC at a single institution from 2006 to 2018 were retrospectively reviewed. A CR-POPF was defined as International Study Group of Pancreatic Surgery (ISGPS) grade B or C fistula. Uni- and multivariable logistic regression analysis assessed factors associated with CR-POPF after DP. Seventy-eight patients met the inclusion criteria, 51 per cent were female, 51 per cent were white, and the average age was 59 ± 15 years. The median BMI was 26 (IQR 24-29). Of all, 19 per cent (n = 15) of patients had a CR-POPF. With a mean follow-up of 2.8 ± 2.5 years, the presence of a CR-POPF was not associated with survival (P = 0.17). On univariable logistic regression, older age was associated with a decreased risk of CR-POPF (odds ratio (OR) = 0.95, P = 0.015). Increasing BMI was associated with an increased risk of CR-POPF (OR = 1.1, P = 0.044). On multivariate analysis, after controlling for multiple factors, BMI (OR = 1.12, P = 0.035) was the only factor associated with the development of a CR-POPF, whereas older age (OR = 0.94, P < 0.001) was slightly protective. Increasing BMI is associated with an increased risk of CR-POPF after DP for PDAC. These findings should be considered during preoperative counseling. Efforts to diminish the risk of CR-POPF should be focused on patients with higher BMI.


Assuntos
Adenocarcinoma/cirurgia , Obesidade/complicações , Pancreatectomia/efeitos adversos , Fístula Pancreática/etiologia , Neoplasias Pancreáticas/cirurgia , Índice de Massa Corporal , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
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