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1.
PLoS One ; 19(3): e0297593, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38547258

RESUMO

The traditional supply-side-driven e-commerce modes provide consumers with massive amounts of structured information about goods and services. Due to the lack of a tailor-made ability to describe, explain, and accurately understand unstructured service demands, existing technologies and service modes still struggle to fully explore, articulate, and meet the personalized, high-quality, and urgent service demands of the disadvantaged groups in e-commerce. This paper innovatively proposes the concept of "integrated services on demand" and develops its C2B2C2B2C-based "Qbnb" e-commerce mode, operation mechanism and intermediary platform architecture. After conducting exploratory operation training, it demonstrates that the Qbnb mode can effectively achieve centralized allocation of idle social surplus service capacity to cater to the needs of disadvantaged groups in e-commerce. Compared to the traditional e-commerce service mode, Qbnb will significantly expand service demand and capacity, achieve higher service efficiency, and create a broader service consumption market, resulting in many more job opportunities.


Assuntos
Comércio , Eficiência , Tecnologia
2.
Disaster Med Public Health Prep ; 17: e502, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37800399

RESUMO

OBJECTIVE: Major epidemics have had a huge impact on the manufacturing industry. This study aimed to explore knowledge innovation in the field of emergency manufacturing during pandemics with a systematic quantitative analysis. METHODS: Based on the Web of Science (WOS) Core Collection, the bibliometric method and the CiteSpace tool were used. RESULTS: A total of 286 literature were obtained from the WOS database. During coronavirus disease (COVID-19), there was a surge in the number of publications. A new field of research on pandemic-triggered emergency manufacturing is gradually forming with accumulated research output. The analysis of the document co-citation showed how the research on pandemic situations and viruses brought emergency manufacturing into the research scope of scholars, and what attempts were made by the original scholars. Pandemic-triggered research hotspots and research trends in the post-pandemic era mainly boiled down to 3 aspects: technological innovation, material innovation, and management innovation in the field of emergency manufacturing. CONCLUSIONS: COVID-19 strengthened academic exchange and cooperation and promotes knowledge output in this field. This study provides an in-depth perspective for emergency manufacturing research and helps researchers realize the panorama of this field and establish future research directions.


Assuntos
COVID-19 , Infecções por Coronavirus , Coronavirus , Humanos , Pandemias , Bibliometria , COVID-19/epidemiologia
3.
Z Gesundh Wiss ; : 1-12, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36844446

RESUMO

Aim: Nonpharmaceutical interventions (NPIs) are important strategies to utilize in reducing the negative systemic impact pandemic disasters have on human health. However, early on in the pandemic, the lack of prior knowledge and the rapidly changing nature of pandemics make it challenging to construct effective epidemiological models that can be used for anti-contagion decision-making. Subject and methods: Based on the parallel control and management theory (PCM) and epidemiological models, we developed a Parallel Evolution and Control Framework for Epidemics (PECFE), which can optimize epidemiological models according to the dynamic information during the evolution of pandemics. Results: The cross-application between PCM and epidemiological models enabled us to successfully construct an anti-contagion decision-making model for the early stages of COVID-19 in Wuhan, China. Using the model, we estimated the effects of gathering bans, intra-city traffic blockades, emergency hospitals, and disinfection, forecasted pandemic trends under different NPIs strategies, and analyzed specific strategies to prevent pandemic rebounds. Conclusion: The successful simulation and forecasting of the pandemic showed that the PECFE could be effective in constructing decision models during pandemic outbreaks, which is crucial for emergency management where every second counts. Supplementary Information: The online version contains supplementary material available at 10.1007/s10389-023-01843-2.

4.
World J Clin Cases ; 10(14): 4601-4607, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35663067

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infections in the population are mostly subclinical, inapparent, or latent. However, it is rare in brain tissue. Most reported CMV encephalitis cases were patients with immunodeficiency. The diagnosis and detection rate of CMV encephalitis in patients with normal immune function needs to be further improved. CASE SUMMARY: An 86-year-old male was admitted due to a sudden onset of unconsciousness for 3 h. The patient developed status epilepticus and was relieved after antiepileptic treatment. Encephalitis was considered due to the high signals of diffusion-weighted imaging sequences in the right central region by magnetic resonance imaging. Metagenomic next-generation sequencing (mNGS) of blood and cerebrospinal fluid revealed CMV, with unique reads number being 614 and 1, respectively. Simultaneous quantitative PCR results showed CMV positive in blood samples and negative in cerebrospinal fluid samples. The patient was finally diagnosed as CMV encephalitis with status epilepticus. After the antiviral, hormonal, and γ-globulin pulse therapy, the patient's condition improved, and he was finally discharged. CONCLUSION: mNGS could be a reliable approach for the diagnosis of CMV encephalitis, with high efficiency, sensitivity, and specificity.

5.
Brain Lang ; 219: 104961, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33965686

RESUMO

Previous studies have shown that reading experience reshapes speech processing. The orthography can be implemented in the brain by restructuring the phonological representations or being co-activated during spoken word recognition. This study utilized event-related functional magnetic resonance imaging and functional connectivity analysis to examine the neural mechanism underlying two types of orthographic effects in the Chinese auditory semantic category task, namely phonology-to-orthography consistency (POC) and homophone density (HD). We found that the POC effects originated from the speech network, suggesting that sublexical orthographic information could change the organization of preexisting phonological representations when learning to read. Meanwhile, the HD effects were localized to the left fusiform and lingual gyrus, suggesting that lexical orthographic knowledge may be activated online during spoken word recognition. These results demonstrated the different natures and neural mechanisms for the POC and HD effects on Chinese spoken word recognition.


Assuntos
Percepção da Fala , China , Humanos , Idioma , Fonética , Leitura , Semântica , Fala
6.
J Phys Chem Lett ; 11(18): 7624-7629, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32820925

RESUMO

The realization of high-performance optoelectronic devices requires excellent charge-transporting layers and efficient carrier recombination. Herein, we synthesized cesium tungsten bronze (Cs0.32WO3) nanocrystals and utilized them as the hole-transporting material to fabricate all-inorganic perovskite light-emitting diodes (PeLEDs). Due to the excellent carrier balance characteristics via comparison between the hole-only device and electron-only device, the all-inorganic PeLEDs with CsPbBr3 as the light-emitting layer present the maximum current efficiency of 31.51 cd/A and external quantum efficiency (EQE) of 8.48%, which are self-evidently enhanced compared with the PEDOT:PSS (14.78 cd/A, 4.03%) and WO3 (24.75 cd/A, 6.18%) based devices. Considering the remarkably improved device performance, the proposed HTL of Cs0.32WO3 is promising, acting as a favorable building block for high-efficiency light-emitting devices.

7.
Eur J Oper Res ; 287(3): 1131-1148, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-32834432

RESUMO

Governments face difficulties in policy making in many areas such as health, food safety, and large-scale projects where public perceptions can be misplaced. For example, the adoption of the MMR vaccine has been opposed due to the publicity indicating an erroneous link between the vaccine and autism. This research proposes the "Parallel Evolution and Response Decision Framework for Public Sentiments" as a real-time decision-making method to simulate and control the public sentiment evolution mechanisms. This framework is based on the theories of Parallel Control and Management (PCM) and System Dynamics (SD) and includes four iterative steps: namely, SD modelling, simulating, optimizing, and controlling. A concrete case of an anti-nuclear mass incident that sparked public sentiment in China is introduced as a study sample to test the effectiveness of the proposed method. In addition, the results indicate the effects by adjusting the key control variables of response strategies. These variables include response time, response capacity, and transparency of the government regarding public sentiment. Furthermore, the advantages and disadvantages of the proposed method will be analyzed to determine how it can be used by policy makers in predicting public opinion and offering effective response strategies.

9.
Front Physiol ; 9: 1224, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30233401

RESUMO

The body temperatures of teleost species fluctuate following changes in the aquatic environment. As such, decreased water temperature lowers the rates of biochemical reactions and affects many physiological processes, including active transport-dependent ion absorption. Previous studies have focused on the impacts of low temperature on the plasma ion concentrations or membrane transporters in fishes. However, very few in vivo or organism-level studies have been performed to more thoroughly elucidate the process of acclimation to low temperatures. In the present study, we compared the strategies for cold acclimation between stenothermic tilapia and eurythermic goldfish. Whole-body calcium content was more prominently diminished in tilapia than in goldfish after long-term cold exposure. This difference can be attributed to alterations in the transportation parameters for Ca2+ influx, i.e., maximum velocity (Vmax ) and binding affinity (1/Km ). There was also a significant difference in the regulation of Ca2+ efflux between the two fishes. Transcript levels for Ca2+ related transporters, including the Na+/Ca2+ exchanger and epithelial Ca2+ channel, were similarly regulated in both fishes. However, upregulation of plasma membrane Ca2+ATPase expression was more pronounced in goldfish than in tilapia. In addition, enhanced Na+/K+-ATPase abundance, which provides the major driving force for ion absorption, was only detected in tilapia, while upregulated Na+/K+-ATPase activity was only detected in goldfish. Based on the results of the present study, we have found that goldfish and tilapia differentially regulate gill epithelial plasma membrane Ca2+-ATPase (PMCA) expression and Na+/K+-ATPase activity in response to cold environments. These regulatory differences are potentially linked to more effective regulation of Ca2+ influx kinetics and better maintenance of whole body calcium content in goldfish than in tilapia.

10.
ACS Appl Mater Interfaces ; 9(42): 37031-37040, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-28959880

RESUMO

Bernal- and rhombohedral-stacked trilayer graphene (B- and r-TLG) on nickel (Ni) and iridium (Ir) films acting as bottom electrodes (BEs) of silver electrochemical metallization cells (Ag-EMCs) have been investigated in this study. Prior to the fabrication of the EMC devices, Raman mapping and atomic force microscopy are applied to identify the B- and r-TLG sheets, with the latter revealing a significant D peak and a rough surface for the Ir film. The Ag-EMCs with the stacked BE of r-TLG on the Ir film show a conductive mechanism of Schottky emission at the positive top electrode bias for both high- and low-resistance states that can be examined by the resistance change with the device area and are modulated by pulse bias operation. Thus, an effective electron barrier height of 0.262 eV at the r-TLG and Ir interface is obtained because of the conspicuous energy gap of r-TLG on the Ir film and the van der Waals (vdW) gap between the r-TLG and Ir contact metal. With the use of Ni instead of Ir contact metal, the Ag-EMCs with TLG BE demonstrate +0.3 V/-0.75 V operation voltages, more than 104 s data retention at 115 °C and 250 times endurance testing, making the TLG sheets suitable for low-power nonvolatile memory applications on flexible substrates.

11.
Brain Lang ; 157-158: 51-62, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27174851

RESUMO

Studies of alphabetic language have shown that orthographic knowledge influences phonological processing during spoken word recognition. This study utilized the Event-Related Potentials (ERPs) to differentiate two types of phonology-to-orthography (P-to-O) mapping consistencies in Chinese, namely homophone density and orthographic consistency. The ERP data revealed an orthographic consistency effect in the frontal-centrally distributed N400, and a homophone density effect in central-posteriorly distributed late positive component (LPC). Further source analyses using the standardized low-resolution electromagnetic tomography (sLORETA) demonstrated that the orthographic effect was not only localized in the frontal and temporal-parietal regions for phonological processing, but also in the posterior visual cortex for orthographic processing, while the homophone density effect was found in middle temporal gyrus for lexical-semantic selection, and in the temporal-occipital junction for orthographic processing. These results suggest that orthographic information not only shapes the nature of phonological representations, but may also be activated during on-line spoken word recognition.


Assuntos
Compreensão/fisiologia , Percepção da Fala/fisiologia , Fala , Adolescente , Adulto , Povo Asiático/psicologia , Córtex Cerebral/fisiologia , China , Potenciais Evocados , Feminino , Humanos , Masculino , Fonética , Semântica , Adulto Jovem
12.
Artigo em Inglês | MEDLINE | ID: mdl-23533502

RESUMO

Pomegranates are widely consumed either as fresh fruit or in beverage form as juice and wine. Ellagic acid possesses potent antioxidative properties; it is known to be an effective phytotherapeutic agent with antimutagenic and anticarcinogenic qualities. Ellagic acid (20 to 80 µ M) exhibited a potent activity in inhibiting platelet aggregation stimulated by collagen; however, it did not inhibit platelet aggregation stimulated by thrombin, arachidonic acid, or U46619. Treatment with ellagic acid (50 and 80 µ M) significantly inhibited platelet activation stimulated by collagen; this alteration was accompanied by the inhibition of relative [Ca(2+)] i mobilization, and the phosphorylation of phospholipase C (PLC) γ 2, protein kinase C (PKC), mitogen-activated protein kinases (MAPKs), and Akt, as well as hydroxyl radical (OH(●)) formation. In addition, ellagic acid also inhibited p38 MAPK and Akt phosphorylation stimulated by hydrogen peroxide. By contrast, ellagic acid did not significantly affect PKC activation and platelet aggregation stimulated by PDBu. This study is the first to show that, in addition to being considered a possible agent for preventing tumor growth, ellagic acid possesses potent antiplatelet properties. It appears to initially inhibit the PLCγ2-PKC cascade and/or hydroxyl radical formation, followed by decreased phosphorylation of MAPKs and Akt, ultimately inhibiting platelet aggregation.

13.
Opt Express ; 21(24): 30065-73, 2013 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-24514556

RESUMO

This paper demonstrates that quantum-confined Stark effect (QCSE) within the multiple quantum wells (MQWs) can be suppressed by the growths of InGaN-based light-emitting diodes (LEDs) on the nano-sized patterned c-plane sapphire substrates (PCSSs) with reducing the space. The efficiency droop is also determined by QCSE. As verified by the experimentally measured data and the ray-tracing simulation results, the suppressed efficiency droop for the InGaN-based LED having the nano-sized PCSS with a smaller space of 200 nm can be acquired due to the weaker function of the QCSE within the MQWs as a result of the smaller polarization fields coming from the lower compressive strain in the corresponding epitaxial layers.

14.
Haematologica ; 98(5): 793-801, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23065519

RESUMO

Thrombin activates platelets mainly through protease-activated receptor (PAR)1 and PAR4. However, downstream platelet signaling between PAR1 and PAR4 is not yet well understood. This study investigated the relationship between nSMase/ceramide and the NF-κB signaling pathway in PARs-mediated human platelet activation. The LC-MS/MS, aggregometry, flow cytometry, immunoprecipitation, and mesenteric microvessels of mice were used in this study. Human platelets stimulated by thrombin, 3-OMS (a neutral sphingomyelinase [nSMase] inhibitor) and Bay11-7082 (an NF-κB inhibitor) significantly inhibited platelet activation such as P-selectin expression. Thrombin also activated IκB kinase (IKK)ß and IκBα phosphorylation; such phosphorylation was inhibited by 3-OMS and SB203580 (a p38 MAPK inhibitor). Moreover, 3-OMS abolished platelet aggregation, IKKß, and p38 MAPK phosphorylation stimulated by PAR4-AP (a PAR4 agonist) but not by PAR1-AP (a PAR1 agonist). Immunoprecipitation revealed that nSMase was directly associated with PAR4 but not PAR1 in resting platelets. In human platelets, C24:0-ceramide is the predominant form of ceramides in the LC/MS-MS assay; C24:0-ceramide increases after stimulation by thrombin or PAR4-AP, but not after stimulation by PAR1-AP. We also found that C2-ceramide (a cell-permeable ceramide analog) activated p38 MAPK and IKKß phosphorylation in platelets and markedly shortened the occlusion time of platelet plug formation in vivo. This study demonstrated that thrombin activated nSMase by binding to PAR4, but not to PAR1, to increase the C24:0-ceramide level, followed by the activation of p38 MAPK-NF-κB signaling. Our results showed a novel physiological significance of PAR4-nSMase/ceramide-p38 MAPK-NF-κB cascade in platelet activation.


Assuntos
Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Ceramidas/metabolismo , NF-kappa B/metabolismo , Receptores de Trombina/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Trombina/farmacologia , Humanos , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária , Ligação Proteica , Transdução de Sinais/efeitos dos fármacos , Esfingosina/análogos & derivados , Esfingosina/farmacologia , Espectrometria de Massas em Tandem , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
J Nutr Biochem ; 24(6): 1086-95, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23246160

RESUMO

Sulforaphane is a naturally occurring isothiocyanate, which can be found in cruciferous vegetables such as broccoli and cabbage. Sulforaphane was found to have very potent inhibitory effects on tumor growth through regulation of diverse mechanisms. However, no data are available concerning the effects of sulforaphane on platelet activation and its relative issues. Activation of platelets caused by arterial thrombosis is relevant to a variety of cardiovascular diseases. Hence, the aim of this study was to examine the in vivo antithrombotic effects of sulforaphane and its possible mechanisms in platelet activation. Sulforaphane (0.125 and 0.25 mg/kg) was effective in reducing the mortality of ADP-induced acute pulmonary thromboembolism in mice. Other in vivo studies also revealed that sulforaphane (0.25 mg/kg) significantly prolonged platelet plug formation in mice. In addition, sulforaphane (15-75 µM) exhibited more-potent activity of inhibiting platelet aggregation stimulated by collagen. Sulforaphane inhibited platelet activation accompanied by inhibiting relative Ca(2+) mobilization; phosphorylation of phospholipase C (PLC)γ2, protein kinase C (PKC), mitogen-activated protein kinases (MAPKs) and Akt; and hydroxyl radical (OH(●)) formation. Sulforaphane markedly increased cyclic (c)AMP, but not cyclic (c)GMP levels, and stimulated vasodilator-stimulated phosphoprotein (VASP) phosphorylation. SQ22536, an inhibitor of adenylate cyclase, but not ODQ (1H-[1,2,4]Oxadiazolo[4,3-a]quinoxal in-1-one), an inhibitor of guanylate cyclase, obviously reversed the sulforaphane-mediated effects on platelet aggregation; PKC activation, p38 MAPK, Akt and VASP phosphorylation; and OH(●) formation. Furthermore, a PI3-kinase inhibitor (LY294002) and a p38 MAPK inhibitor (SB203580) both significantly diminished PKC activation and p38 MAPK and Akt phosphorylation; in contrast, a PKC inhibitor (RO318220) did not diminish p38 MAPK or Akt phosphorylation stimulated by collagen. This study demonstrates for the first time that in addition to it originally being considered as an agent for prevention of tumor growth, sulforaphane possesses potent antiplatelet activity which may initially activate adenylate cyclase/cAMP, followed by inhibiting intracellular signals (such as the PI3-kinase/Akt and PLCγ2-PKC-p47 cascades) and ultimately inhibiting platelet activation. Therefore, this novel role of sulforaphane may represent a high therapeutic potential for treatment or prevention of cardiovascular diseases.


Assuntos
Adenilil Ciclases/metabolismo , Plaquetas/enzimologia , Fibrinolíticos/farmacologia , Isotiocianatos/farmacologia , Difosfato de Adenosina/metabolismo , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Células Cultivadas , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Ativação Enzimática , Humanos , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Fosfolipase C gama/metabolismo , Ativação Plaquetária/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Sulfóxidos
16.
Head Neck ; 35(2): E49-51, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22422483

RESUMO

BACKGROUND: Free tissue reconstruction after ablation of head and neck malignancy often requires extensive cervical manipulation, which may exacerbate preexisting cervical spondylosis and result in progression to cervical myelopathy. We present a rare case of postoperative quadriplegia caused by cervical spondylotic myelopathy after head and neck reconstruction. METHODS AND RESULTS: A 63-year-old man without a history of cervical spondylosis underwent resection of a gingivo-buccal squamous cell carcinoma with immediate reconstruction with free fibula osteocutaneous flap. On postoperative day 4, the patient was found to have quadriplegia. MRI demonstrated severe cervical myelopathy. Decompressive laminectomy was performed. The patient underwent an extensive rehabilitation program but only realized moderate improvement. CONCLUSION: Cervical spondylotic myelopathy is a rare but disastrous complication of head and neck surgery. We hypothesize that it is potentially avoidable with heightened awareness of this disease entity, preoperative identification of patients at risk, and prophylactic interventions


Assuntos
Esvaziamento Cervical/efeitos adversos , Procedimentos de Cirurgia Plástica/efeitos adversos , Quadriplegia/cirurgia , Doenças da Medula Espinal/diagnóstico , Espondilose/cirurgia , Retalhos Cirúrgicos/efeitos adversos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Descompressão Cirúrgica/métodos , Descompressão Cirúrgica/reabilitação , Seguimentos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Esvaziamento Cervical/métodos , Quadriplegia/etiologia , Doenças Raras , Procedimentos de Cirurgia Plástica/métodos , Medição de Risco , Doenças da Medula Espinal/cirurgia , Espondilose/diagnóstico , Resultado do Tratamento
17.
Plast Reconstr Surg ; 130(1): 64-72, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22743874

RESUMO

BACKGROUND: Composite tissue allotransplantation holds promise in reconstructive surgery, but its application is limited by the need for long-term immunosuppression. The objective of this study was to investigate the feasibility of low-dose cyclosporine and vascularized bone allotransplantation in prolonging the survival of vascularized adipose tissue allograft. METHODS: In the adipose tissue allograft model, adipose tissue allografts based on superficial epigastric vessels from Lewis-Brown-Norway rats were allotransplanted into Lewis rats. In the adipose tissue and bone marrow allograft model, combined vascularized bone marrow and adipose tissues were allografted from Brown Norway rats into Lewis rats. The graft survival, the onset and progression of rejection, and the effects of cyclosporine at different dosages and treatment durations were recorded. A rejection grading system was created based on gross observation and was correlated with histologic examinations. RESULTS: Even at a low dose of 2 mg/kg/day, cyclosporine continued to provide effective allograft protection. Tolerance was not observed in either model. Adipose tissue survival after discontinuation of cyclosporine was independent of treatment duration. The inclusion of vascularized bone to the adipose tissue allograft provided an additional protective effect. This effect was synergistic with concomitant use of immunosuppressant. CONCLUSIONS: Adipose tissue allotransplantation is a potential reconstructive option that requires only minimal use of immunosuppressants. Its survival can be further prolonged with simultaneous bone marrow allotransplantation.


Assuntos
Tecido Adiposo/transplante , Transplante de Medula Óssea/métodos , Medula Óssea/irrigação sanguínea , Ciclosporina/administração & dosagem , Sobrevivência de Enxerto/fisiologia , Transplante de Pele/métodos , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Imunossupressores/administração & dosagem , Masculino , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Transplante Homólogo
18.
Microsurgery ; 32(4): 314-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22451230

RESUMO

A pedicle flap with distal segment compromise is classically managed by allowing tissue demarcation, debridement of non-viable tissue, and local tissue manipulation to achieve wound closure. When aggressive debridement leaves insufficient tissue for defect coverage, the original flap is often discarded. We present a case of distal necrosis of a pedicle internal mammary artery perforator flap for cheek reconstruction. The flap, which was rendered too small after debridement for defect coverage in its pedicle form, was converted to a free flap. The technical details of such conversion and potential feasibility of applying this conversion to other compromised pedicle flaps are discussed. We hypothesized that the principle of "free-ization" can be applied effectively for salvage of other failing pedicle flaps with axial blood supply.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Retalhos de Tecido Biológico/irrigação sanguínea , Artéria Torácica Interna/cirurgia , Neoplasias Bucais/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Falha de Tratamento
20.
Eur J Pharmacol ; 649(1-3): 140-9, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20883689

RESUMO

Arterial thromboses are mostly composed of platelets adherent to ruptured endothelial surfaces. Platelets are anucleated cells; therefore, they represent an excellent and unique model to selectively investigate the signaling pathways mediating the nongenomic effects of estrogen. The aim of this study was to examine the signal transduction pathways of 17ß-estradiol in preventing platelet activation. In this study, 17ß-estradiol (5~10 µM) exhibited more-potent activity of inhibiting platelet aggregation stimulated by collagen than other agonists (i.e., thrombin). 17ß-Estradiol-inhibited collagen-stimulated platelet activation accompanied by [Ca(2+)]i mobilization, thromboxane A2 (TxA2) formation, and phospholipase C (PLC)γ2, protein kinase C (PKC), and p38 mitogen-activated protein kinase (MAPK) phosphorylation. 17ß-Estradiol markedly increased cyclic AMP and cyclic GMP levels, nitric oxide (NO) release, vasodilator-stimulated phosphoprotein (VASP) phosphorylation, and endothelial nitric oxide synthase (eNOS) expression. SQ 22536, an inhibitor of adenylate cyclase, markedly reversed the 17ß-estradiol-mediated effects (i.e., platelet aggregation, and PLCγ2, VASP, and eNOS phosphorylation). Furthermore, ICI 182,780, a pure estrogen receptor antagonist, also reversed the 17ß-estradiol-mediated effects on platelet aggregation and eNOS activation. In conclusion, the most important findings of this study demonstrate for the first time that the inhibitory effect of 17ß-estradiol in platelet activation involves activation of the cyclic AMP-eNOS/NO-cyclic GMP pathway, resulting in inhibition of PLCγ2 and p38 MAPK activation, which may lower the incidence of cardiovascular events in postmenopausal women.


Assuntos
AMP Cíclico/metabolismo , Estradiol/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Transdução de Sinais/efeitos dos fármacos , Inibidores de Adenilil Ciclases , Adulto , Doenças Cardiovasculares/prevenção & controle , Colágeno/antagonistas & inibidores , Colágeno/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Antagonistas de Estrogênios/farmacologia , Feminino , Humanos , Masculino , Óxido Nítrico/metabolismo , Concentração Osmolar , Adulto Jovem
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