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1.
Int J Ophthalmol ; 17(3): 435-443, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721521

RESUMO

AIM: To investigate the underlying mechanism of dry environment (autumn dryness) affecting the lacrimal glands in rats. METHODS: Twenty Sprague-Dawley rats were randomly divided into two groups. The rats were fed in specific pathogen free environment as the control group (n=10), and the rats fed in dry environment as the dryness group (n=10). After 24d, lacrimal glands were collected from the rats. The tissues morphology was observed by hematoxylin-eosin (HE) staining. Tandem mass tags (TMT) quantitative proteomics analysis technology was used to screen the differential expressed proteins of lacrimal glands between the two groups, then bioinformatics analysis was performed. Further, the immunohistochemical (IHC) method was used to verify the target proteins. RESULTS: In dryness group, the lacrimal glands lobule atrophied, the glandular cavities enlarged, the sparse nuclear distribution and scattered inflammatory infiltration between the acinus were observed. The proteomics exhibited that a total of 195 up-regulated and 236 down-regulated differential expressed proteins screened from the lacrimal glands of rats. It was indicated that the biological processes (BP) of differential expressed proteins mainly included cell processes and single BP. The cellular compositions of differential expressed proteins mainly located in cells, organelles. The molecular functions of differential expressed proteins mainly included binding, catalytic activity. Moreover, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that the differential expressed proteins mainly involved lysosome, complement and coagulation cascade, and ribosome pathway. The IHC result verified that the up-regulated expression proteins of Protein S100A9 (S100A9), Annexin A1 (Anxa1), and Clusterin (Clu) in lacrimal glands of rats in dryness group were higher than control group. CONCLUSION: The up-regulated expression proteins of S100A9, Anxa1, and Clu may be the potential mechanisms of dry eye symptoms caused by dry environment. This study provides clues of dry environments causing eye-related diseases for further studies.

2.
PLoS Pathog ; 18(8): e1010718, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35951530

RESUMO

Viruses are ubiquitous intracellular genetic parasites that heavily rely on the infected cell to complete their replication life cycle. This dependency on the host machinery forces viruses to modulate a variety of cellular processes including cell survival and cell death. Viruses are known to activate and block almost all types of programmed cell death (PCD) known so far. Modulating PCD in infected hosts has a variety of direct and indirect effects on viral pathogenesis and antiviral immunity. The mechanisms leading to apoptosis following virus infection is widely studied, but several modalities of PCD, including necroptosis, pyroptosis, ferroptosis, and paraptosis, are relatively understudied. In this review, we cover the mechanisms by which viruses activate and inhibit PCDs and suggest perspectives on how these affect viral pathogenesis and immunity.


Assuntos
Viroses , Vírus , Apoptose , Morte Celular , Humanos , Piroptose , Vírus/metabolismo
3.
Anal Chim Acta ; 1183: 338973, 2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34627508

RESUMO

In this study, the application of carbon dots (CDs) modified NaYF4:Yb, Er nanoparticles (UCNPs@CDs) as the fluorescent nanoprobe for simultaneous detection of Fe2+ and Fe3+ was investigated. Fe3+ quantification (5-80 µmol L-1) was achieved, as a result of Fe3+ induced fluorescence quenching of UCNPs@CDs at 434 nm (under the 336 nm excitation). The chelate (Fe2+-phen) formed by Fe2+ and 1,10-phenanthroline had a broad absorption centered at 510 nm, due to inner filter effect (IFE), Fe2+ quantification (4-120 µmol L-1) was achieved as a result of (Fe2+-phen) induced fluorescence quenching of UCNPs@CDs at 545 nm (under the 980 nm excitation). The resultant UCNPs@CDs probe, with excellent anti-interference capability, favorable fluorescence stability, and convincing performance in real sample analysis, showed promising application in simultaneous detection of Fe2+ and Fe3+.


Assuntos
Carbono , Nanopartículas , Íons , Ferro , Espectrometria de Fluorescência
4.
Oncol Rep ; 43(5): 1479-1490, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32323804

RESUMO

Glioblastoma (GBM) is the most prevalent and lethal primary intrinsic brain cancer. The disease is essentially incurable, with glioblastomas characterized by resistance to both chemotherapy and radiotherapy, as well as by rapid tumor progression, all of which are mainly ascribed to glioma stem­like cells (GSLCs). In the present study, an improved model that is more similar to clinical GBM was constructed. Twenty clinical glioma samples were collected to obtain primary low­grade tumor cells. The cells were either maintained in serum­free medium as primary glioma­based cells (PGBCs) or cultured in the same medium with CHIR99021 as GSLCs. Then, the molecular and ultrastructural differences between the two cell groups were determined. Furthermore, the proliferation and migration of the GSLCs were examined and the potential mechanisms were investigated. Finally, temozolomide resistance in vitro and in the mouse model was assessed to study the properties of the induced GSLCs. The primary low­grade tumor cells extracted from surgical samples were enriched with GSLC properties, with high expression levels of CD133 and Nestin in 100 nM CHIR99021. The GSLCs exhibited high proliferation and migration. Furthermore, the expression of the PI3K/AKT signaling pathway and that of related genes and proteins were significantly enhanced by CHIR99021. The animal study also revealed high levels of STAT3, mTOR, NF­κB, and VEGF in the GSLC­transplanted mice. CHIR99021 could stably enhance GSLC properties in patient­derived glioma samples. It may provide a useful model for further study, helping to understand the pathogenesis of therapeutic resistance and to screen drug candidates.


Assuntos
Antígeno AC133/metabolismo , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Células-Tronco Neoplásicas/patologia , Nestina/metabolismo , Piridinas/efeitos adversos , Pirimidinas/efeitos adversos , Animais , Neoplasias Encefálicas/metabolismo , Técnicas de Cultura de Células , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Masculino , Camundongos , Gradação de Tumores , Transplante de Neoplasias , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/transplante , Piridinas/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Regulação para Cima
5.
J Cardiovasc Electrophysiol ; 29(10): 1436-1443, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30016000

RESUMO

INTRODUCTION: Deficiency of testosterone was associated with the susceptibility of atrial fibrillation (AF). Angiotensin-II (AngII) receptor antagonists were shown to reduce AF by improving atrial electrical remodeling. This study investigated the effects and mechanism of valsartan, an AngII receptor antagonist, on the susceptibility to AF with testosterone deficiency. METHODS AND RESULTS: Five-week-old male ICR mice were castrated and valsartan was administered orally (50 mg/kg/d). High-frequency electrical stimulation method was used to induce atrial arrhythmia. Patch-clamp technique was used for recording action potential duration (APD), transient outward potassium current ( I to ), sustained outward potassium current ( I ksus ), and late sodium current ( I Na-L ). Optical mapping technique was used to examine atrial conduction velocity (CV). The expression of connexin40 (Cx40) and Cx43 were detected by Western blot analysis. The occurrence rate of AF was significantly increased in castrated mice and APDs measured at 50% and 90% repolarization were markedly prolonged in castrated mice than controls, which were alleviated by the administration of valsartan. Valsartan suppressed the increase of INa-L and rescued the reduction of Ito and Iksus in castrated mice. The left atrial CV in castrated mice was decreased and the expression of Cx43 reduced than controls, which were restored after valsartan treatment. CONCLUSIONS: Valsartan reduced the susceptibility of AF in castrated mice, which may be related to the inhibition of action potential prolongation and improvement of atrial conduction impairment. This study indicates that valsartan may represent a useful agent for the prevention of AF pathogenesis in elderly male patients.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Antiarrítmicos/farmacologia , Fibrilação Atrial/prevenção & controle , Sistema de Condução Cardíaco/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Orquiectomia , Valsartana/farmacologia , Animais , Fibrilação Atrial/etiologia , Fibrilação Atrial/metabolismo , Fibrilação Atrial/fisiopatologia , Estimulação Cardíaca Artificial , Células Cultivadas , Conexina 43/metabolismo , Modelos Animais de Doenças , Sistema de Condução Cardíaco/metabolismo , Sistema de Condução Cardíaco/fisiopatologia , Masculino , Camundongos Endogâmicos ICR , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Potássio/metabolismo , Sódio/metabolismo , Testosterona/deficiência , Fatores de Tempo
6.
Sci Rep ; 8(1): 5107, 2018 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-29572513

RESUMO

Graphene-based optoelectronic devices have attracted much attention due to their broadband photon responsivity and fast response time. However, the performance of such graphene-based photodetectors is greatly limited by weak light absorption and low responsivity induced by the gapless nature of graphene. Here, we achieved a high responsivity above 103 AW-1 for Ultraviolet (UV) light in a hybrid structure based phototransistor, which consists of CVD-grown monolayer graphene and ZnSe/ZnS core/shell quantum dots. The photodetectors exhibit a selective photo responsivity for the UV light with the wavelength of 405 nm, confirming the main light absorption from QDs. The photo-generated charges have been found to transfer from QDs to graphene channel, leading to a gate-tunable photo responsivity with the maximum value obtained at V G about 15V. A recirculate 100 times behavior with a good stability of 21 days is demonstrated for our devices and another flexible graphene/QDs based photoconductors have been found to be functional after 1000 bending cycles. Such UV photodetectors based on graphene decorated with cadmium-free ZnSe/ZnS quantum dots offer a new way to build environmental friendly optoelectronics.

7.
Sci Rep ; 7(1): 6751, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28754899

RESUMO

Single-walled carbon nanotubes (SWCNTs) offer great potential for field-effect transistors and integrated circuit applications due to their extraordinary electrical properties. To date, as-made SWCNT transistors are usually p-type in air, and it still remains challenging for realizing n-type devices. Herein, we present efficient and reversible electron doping of semiconductor-enriched single-walled carbon nanotubes (s-SWCNTs) by firstly utilizing decamethylcobaltocene (DMC) deposited by a simple spin-coating process at room temperature as an electron donor. A n-type transistor behavior with high on current, large I on /I off ratio and excellent uniformity is obtained by surface charge transfer from the electron donor DMC to acceptor s-SWCNTs, which is further corroborated by the Raman spectra and the ab initio simulation results. The DMC dopant molecules could be reversibly removed by immersion in N, N-Dimethylformamide solvent, indicating its reversibility and providing another way to control the carrier concentration effectively as well as selective removal of surface dopants on demand. Furthermore, the n-type behaviors including threshold voltage, on current, field-effect mobility, contact resistances, etc. are well controllable by adjusting the surface doping concentration. This work paves the way to explore and obtain high-performance n-type nanotubes for future complementary CMOS circuit and system applications.

8.
World Neurosurg ; 103: 484-492, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28427981

RESUMO

OBJECTIVES: Recently, we reported a tendency toward spontaneous hemorrhage in both the preoperative and postoperative periods in patients with intracranial epidermoid cyst (EC). According to our experience, this tendency for spontaneous hemorrhage was partly caused by the pathologic blood vessels adjacent to the EC. This study was designed to testify this hypothesis. METHODS: Twenty-three removable pericystic or intracystic blood vessels from 17 patients with EC were collected during surgery and were then examined by transmission electron microscopy. The microvascular structure in gliomas was chosen as the control. RESULTS: Under electron microscopy, variant pathologic changes of vessels were found in all patients with EC. In the tunicae intima, we found vacuolization, apoptosis, necrosis, and intralumenal protrusion of endothelial cells, as well as swollen basement and highly flexed and discontinued elastic plate. In the tunicae media, vacuolization and swollen mitochondria were found in muscular cells. In the tunicae adventitia, extravascular erythrocytes, edema or apoptosis of pericytes, collagen predominance, and inflammatory cell infiltration and destruction were found. Neuron denature and necrosis were found in the peripheral brain tissue. In the microvascular structure of 5 glioma specimens, we found enlargement and hyperplasia of endothelial cells, swollen basement membrane, swollen pericytes, and astrocytic hyperplasia and neuron denature in adjacent brain tissues. CONCLUSIONS: Our findings provide strong evidence for the hypothesis that intracystic or pericystic vascular degeneration or destruction accounts for the spontaneous hemorrhage tendency before and after surgical resection of ECs.


Assuntos
Vasos Sanguíneos/ultraestrutura , Neoplasias Encefálicas/irrigação sanguínea , Células Endoteliais/ultraestrutura , Cisto Epidérmico/irrigação sanguínea , Glioma/irrigação sanguínea , Miócitos de Músculo Liso/ultraestrutura , Pericitos/ultraestrutura , Adolescente , Adulto , Túnica Adventícia/ultraestrutura , Apoptose , Astrócitos/ultraestrutura , Membrana Basal/ultraestrutura , Encefalopatias/cirurgia , Neoplasias Encefálicas/ultraestrutura , Colágeno/ultraestrutura , Endotélio Vascular/ultraestrutura , Cisto Epidérmico/cirurgia , Feminino , Glioma/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Músculo Liso Vascular/ultraestrutura , Necrose , Procedimentos Neurocirúrgicos , Hemorragia Pós-Operatória , Túnica Íntima/ultraestrutura , Vacúolos/ultraestrutura , Adulto Jovem
9.
Chin Med J (Engl) ; 130(8): 936-942, 2017 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-28397723

RESUMO

BACKGROUND: Thyrotropin-secreting pituitary adenomas (TSHomas) are a rare cause of hyperthyroidism. Somatostatin (SST) analogs work by interacting with somatostatin receptors (SSTRs). This study aimed to evaluate short-term preoperative octreotide (OCT) use in TSHoma patients and to investigate SSTR2 and SSTR5 expression and observe structural changes in tumor tissue. METHODS: We reviewed records and samples from eight TSHoma patients treated between July 2012 and July 2015. We tested immunohistochemically for SSTR2/5 expression and examined TSHoma cells for morphological changes. Signed rank sum test was used to compare the efficacy of short-term preoperative OCT treatment. RESULTS: OCT treatment (median time: 7.9 days, range: 3-16 days; median total dose: 1.8 mg, range: 0.9-4.2 mg) led to significant decrease in all patients' thyroid hormone levels (FT3 [nmol/L]: 8.33 [7.02, 12.29] to 4.67 [3.52, 5.37] [P = 0.008]; FT4 [pmol/L]: 25.36 [21.34, 28.99] to 16.66 [14.88, 21.49] [P = 0.016]; and TSH [µU/ml]: 5.80 [4.37, 6.78] to 0.57 [0.19, 1.24] [P = 0.008]). All the eight tumor specimens expressed high SSTR2 protein levels; 5/8 expressed high SSTR5, but 3/8 that expressed low SSTR5 presented a significantly higher TSH suppression rate (P = 0.036). Electron microscopy showed subcellular level impairments, including clumped nuclear chromatin and reduced cytoplasmic volume. Golgi complexes were observed in the OCT-treated TSHoma specimens. CONCLUSIONS: OCT can control hormone levels and damage the ultrastructure of tumor cells and organelles. Short-term response to OCT may be related to SSTR5 expression. Preoperative SST analog treatment for TSHoma could be considered as a combination therapy.


Assuntos
Octreotida/uso terapêutico , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/metabolismo , Receptores de Somatostatina/metabolismo , Tireotropina/metabolismo , Adulto , Feminino , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade
10.
Heart Rhythm ; 14(7): 1073-1080, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28185917

RESUMO

BACKGROUND: The incidence of atrial fibrillation (AF) is correlated with decreased levels of testosterone in elderly men. Late sodium current may exert a role in AF pathogenesis. OBJECTIVE: The purpose of this study was to explore the effect of testosterone deficiency on AF susceptibility and the therapeutic effect of late sodium current inhibitors in mice. METHODS: Male ICR mice (5 weeks old) were castrated to establish a testosterone deficiency model. One month after castration, dihydrotestosterone 5 mg/kg was administered subcutaneously for 2 months. Serum total testosterone level was assessed by enzyme-linked immunosorbent assay. High-frequency electrical stimulation was used to induce atrial arrhythmias. Whole-cell patch-clamp technique was used to for single-cell electrophysiologic study. RESULTS: Serum dihydrotestosterone levels of castration mice declined significantly but recovered with administration of exogenous dihydrotestosterone. In comparison with sham mice, the number of AF episodes significantly increased by 13.5-fold, AF rate increased by 3.75-fold, and AF duration prolonged in castrated mice. Dihydrotestosterone administration alleviated the occurrence of AF. Action potential duration at both 50% and 90% repolarization were markedly increased in castrated mice compared to sham controls. The late sodium current was enhanced in castrated male mice. These alterations were alleviated by treatment with dihydrotestosterone. Systemic application of the INa-L inhibitors ranolazine, eleclazine, and GS967 inhibited the occurrence of AF in castrated mice. CONCLUSION: Testosterone deficiency contributed to the increased late sodium current, prolonged action potential repolarization, and increased susceptibility to AF. Blocking of late sodium current is beneficial against the occurrence of AF in castrated mice.


Assuntos
Envelhecimento/metabolismo , Fibrilação Atrial , Di-Hidrotestosterona/farmacologia , Orquiectomia/efeitos adversos , Bloqueadores dos Canais de Sódio/farmacologia , Testosterona , Potenciais de Ação/fisiologia , Androgênios/farmacologia , Animais , Fibrilação Atrial/etiologia , Fibrilação Atrial/metabolismo , Fibrilação Atrial/terapia , Masculino , Camundongos , Modelos Animais , Canais de Sódio/metabolismo , Testosterona/deficiência , Testosterona/metabolismo , Resultado do Tratamento
11.
ACS Appl Mater Interfaces ; 8(45): 31289-31294, 2016 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-27781430

RESUMO

A flexible photodetector based on the bulk heterojunction of an organometallic halide perovskites CH3NH3PbI3 and an organic dye Rhodamine B (RhB) has been fabricated via a solution casting process. It showed a high responsivity (Rmax = 43.6 mA/W) to visible lights, short response time (tr ≈ 60 ms, td ≈ 40 ms), high on-off ratio (Ion/Ioff ≈ 287) and satisfactory stability because of its Schottky barrier structure and the dye enhanced light absorption.

12.
CNS Neurosci Ther ; 22(10): 824-35, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27390192

RESUMO

BACKGROUND: Edaravone is widely used for treating ischemic stroke, but it is not still confirmed in intracerebral hemorrhage (ICH) as an ideal medication targeting the brain parenchyma. We aimed to investigate the neuroprotective effects of stereotactic administration of edaravone (SI) into the brain parenchyma. METHODS: Intracerebral hemorrhage rat models were established by infusion of collagenase into the caudate nucleus. Neural functional recovery was assessed using modified neurological severity scores (mNSS). A comparative study of therapeutic effects between SI and intraperitoneal injection of edaravone (IP) involved in cerebral edema, blood-brain barrier (BBB) permeability, hematoma absorption, inflammatory response and neuronal apoptosis. RESULTS: Compared with IP, the mNSS was significantly (P < 0.05) improved by SI; cerebral edema and BBB permeability were dramatically ameliorated (P < 0.05); IL-4 and IL-10 levels increased, but IL-1ß and TNF-α levels significantly decreased; neuron apoptosis decreased markedly (P < 0.05); and caspase-3 and Bax expression significantly dropped, but Bcl-2 increased in SI group (P < 0.05). CONCLUSION: SI markedly improved neurological deficits in ICH rat models via antiinflammatory and antiapoptosis mechanisms and promoted M2-type microglia differentiation. SI was effective in rats with collagenase-induced ICH.


Assuntos
Antipirina/análogos & derivados , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/tratamento farmacológico , Colagenases/toxicidade , Sequestradores de Radicais Livres/administração & dosagem , Animais , Antipirina/administração & dosagem , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiopatologia , Edema Encefálico/tratamento farmacológico , Edema Encefálico/etiologia , Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico por imagem , Citocinas/metabolismo , Modelos Animais de Doenças , Edaravone , Imageamento por Ressonância Magnética , Masculino , Microglia/metabolismo , Microglia/patologia , Proteínas do Tecido Nervoso/metabolismo , Ratos , Ratos Sprague-Dawley , Técnicas Estereotáxicas , Fatores de Tempo , Resultado do Tratamento
13.
Sci Rep ; 6: 23010, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26972749

RESUMO

Interleukin 6 (IL-6) has been shown to be an important regulator of cardiac interstitial fibrosis. In this study, we explored the role of interleukin-6 in the development of diabetic cardiomyopathy and the underlying mechanisms. Cardiac function of IL-6 knockout mice was significantly improved and interstitial fibrosis was apparently alleviated in comparison with wildtype (WT) diabetic mice induced by streptozotocin (STZ). Treatment with IL-6 significantly promoted the proliferation and collagen production of cultured cardiac fibroblasts (CFs). High glucose treatment increased collagen production, which were mitigated in CFs from IL-6 KO mice. Moreover, IL-6 knockout alleviated the up-regulation of TGFß1 in diabetic hearts of mice and cultured CFs treated with high glucose or IL-6. Furthermore, the expression of miR-29 reduced upon IL-6 treatment, while increased in IL-6 KO hearts. Overexpression of miR-29 blocked the pro-fibrotic effects of IL-6 on cultured CFs. In summary, deletion of IL-6 is able to mitigate myocardial fibrosis and improve cardiac function of diabetic mice. The mechanism involves the regulation of IL-6 on TGFß1 and miR-29 pathway. This study indicates the therapeutic potential of IL-6 suppression on diabetic cardiomyopathy disease associated with fibrosis.


Assuntos
Cardiomiopatias Diabéticas/genética , Interleucina-6/genética , MicroRNAs/genética , Miocárdio/metabolismo , Transdução de Sinais/genética , Fator de Crescimento Transformador beta1/genética , Animais , Animais Recém-Nascidos , Western Blotting , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Cultivadas , Cardiomiopatias Diabéticas/induzido quimicamente , Cardiomiopatias Diabéticas/diagnóstico por imagem , Ecocardiografia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibrose/genética , Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Coração/fisiopatologia , Interleucina-6/sangue , Interleucina-6/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocárdio/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estreptozocina , Fator de Crescimento Transformador beta1/metabolismo
14.
Sci Rep ; 6: 23090, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26980284

RESUMO

Double-gated field effect transistors have been fabricated using the SWCNT networks as channel layer and the organic ferroelectric P(VDF-TrFE) film spin-coated as top gate insulators. Standard photolithography process has been adopted to achieve the patterning of organic P(VDF-TrFE) films and top-gate electrodes, which is compatible with conventional CMOS process technology. An effective way for modulating the threshold voltage in the channel of P(VDF-TrFE) top-gate transistors under polarization has been reported. The introduction of functional P(VDF-TrFE) gate dielectric also provides us an alternative method to suppress the initial hysteresis of SWCNT networks and obtain a controllable ferroelectric hysteresis behavior. Applied bottom gate voltage has been found to be another effective way to highly control the threshold voltage of the networked SWCNTs based FETs by electrostatic doping effect.

15.
Chin Med J (Engl) ; 128(2): 186-90, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25591560

RESUMO

BACKGROUND: Contrast-enhanced ultrasound is a dynamic and continuous modality providing real-time view of vascularization and flow distribution patterns of different organs and tumors. In order to evaluate the diagnostic significance of intraoperative contrast-enhanced ultrasound in assessing the resection degree of brain glioma by transmission electron microscopic (TEM) examination, it is important to have specific knowledge about contrast-enhanced ultrasound. Methods : Ultrasound contrast was applied in operations of 120 cases of brain glioma, to evaluate the degree of tumor resection. Biopsy tissues were obtained the suspicious residual tumors surrounding the tumor cavity. The sensitivity and specificity of the residual tumors were determined by the intraoperative ultrasound contrast according to TEM examination results. RESULTS: There were 44 cases of low-grade gliomas and 76 cases of high-grade gliomas. Three hundred and sixty biopsy tissues were obtained. The sensitivity of intraoperative ultrasound contrast in diagnosing the residual tumor was 62.2%, while the specificity degree of it was 92.8%. The consistency coefficient of the ultrasound contrast diagnosis and TEM examination results was 0.584 (Kappa = 0.584), which was between 0.4 and 0.6, therefore it was of medium consistency. Conclusions : Intraoperative ultrasound contrast was of a high sensitivity and specificity in evaluating the excision degree of tumor. The consistency of the residual tumor rate detected, respectively, by ultrasound contrast and TEM examination was of medium consistency. The application of intraoperative ultrasound contrast can improve the resection rate of brain glioma.


Assuntos
Glioma/diagnóstico , Adulto , Idoso , Meios de Contraste , Feminino , Glioma/diagnóstico por imagem , Glioma/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Ultrassonografia , Adulto Jovem
16.
J Neurosurg ; 121 Suppl: 179-87, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25434951

RESUMO

OBJECT: The goal of this study was to assess the clinical and pathological features of benign brain tumors that had been treated with Gamma Knife surgery (GKS) followed by resection. METHODS: In this retrospective chart review, the authors identified 61 patients with intracranial benign tumors who had undergone neurosurgical intervention after GKS. Of these 61 patients, 27 were male and 34 were female; mean age was 49.1 years (range 19-73 years). There were 24 meningiomas, 18 schwannomas, 14 pituitary adenomas, 3 hemangioblastomas, and 2 craniopharyngiomas. The interval between GKS and craniotomy was 2-168 months, with a median of 24 months; for 7 patients, the interval was 10 years or longer. For 21 patients, a craniotomy was performed before and after GKS; in 9 patients, pathological specimens were obtained before and after GKS. A total of 29 patients underwent GKS at the Beijing Tiantan Hospital. All specimens obtained by surgical intervention underwent histopathological examination. RESULTS: Most patients underwent craniotomy because of tumor recurrence and/or exacerbation of clinical signs and symptoms. Neuroimaging analyses indicated tumor growth in 42 patients, hydrocephalus in 10 patients with vestibular schwannoma, cystic formation with mass effect in 7 patients, and tumor hemorrhage in 13 patients, of whom 10 had pituitary adenoma. Pathological examination demonstrated that, regardless of the type of tumor, GKS mainly induced coagulative necrosis of tumor parenchyma and stroma with some apoptosis and, ultimately, scar formation. In addition, irradiation induced vasculature stenosis and occlusion and tumor degeneration as a result of reduced blood supply. GKS-induced vasculature reaction was rarely observed in patients with pituitary adenoma. Pathological analysis of tumor specimens obtained before and after GKS did not indicate increased tumor proliferation after GKS. CONCLUSIONS: Radiosurgery is effective for intracranial benign tumors of small size and deep location and for tumor recurrence after surgical intervention; it is not effective for intracranial tumors with symptomatic mass effect. The radiobiological effects of stereotactic radiosurgery on the benign tumors are mainly caused by cellular and vascular mechanisms. Among the patients in this study, high-dose irradiation did not increase tumor proliferation. GKS can induce primary and secondary effects in tumors, which could last more than 10 years, thereby warranting long-term follow-up after GKS.


Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Radiocirurgia/métodos , Adenoma/patologia , Adenoma/cirurgia , Adolescente , Adulto , Idoso , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/cirurgia , Craniofaringioma/patologia , Craniofaringioma/cirurgia , Feminino , Seguimentos , Hemangioblastoma/patologia , Hemangioblastoma/cirurgia , Humanos , Masculino , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/patologia , Meningioma/cirurgia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Neurilemoma/patologia , Neurilemoma/cirurgia , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos , Adulto Jovem
17.
Neurosurg Rev ; 36(4): 533-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23765214

RESUMO

Despite being widely accepted as an important cause of spontaneous intracranial hemorrhage (ICH), cerebral amyloid angiopathy (CAA) has seldom been studied in the Chinese population. The current study aims to investigate the incidence and features of CAA in surgically treated ICH patients in China. From May 2006 to April 2011, 974 patients admitted to 71 hospitals throughout China for acute spontaneous ICH were studied. Craniotomy for hematoma evacuation was performed. Brain tissue from the superficial side of the suspected residual hematoma cavity, as well as from the cortex and subcortex, was obtained. Congo Red stain and ß-amyloid immunohistochemistry were used for the diagnosis. Each case was assigned a pathological severity score. Of the 974 involved patients, 37.7% were identified with CAA of different degrees. CAA had positive correlation with age and was independent of sex. Most patients had mild CAA with only the superficial vessels involved in lobes instead of the basal ganglia; the patients ≥65 years had more severe pathological score of CAA than those <65 years and had more lobes and cerebellum involved than the latter. More than one third of the surgically treated Chinese ICH patients may have CAA of different degrees.


Assuntos
Angiopatia Amiloide Cerebral/epidemiologia , Hemorragias Intracranianas/epidemiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Peptídeos beta-Amiloides/metabolismo , Povo Asiático , Autopsia , Encéfalo/patologia , Angiopatia Amiloide Cerebral/complicações , China/epidemiologia , Feminino , Humanos , Imuno-Histoquímica , Hemorragias Intracranianas/complicações , Hemorragias Intracranianas/cirurgia , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Estudos Prospectivos , Tomografia Computadorizada por Raios X
18.
Chin Med J (Engl) ; 126(4): 603-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23422175

RESUMO

BACKGROUND: Cerebral amyloid angiopathy (CAA) is one of the main causes of spontaneous intracranial hemorrhage (ICH). No established link is available between pathological scores of CAA and its outcome. This study aimed to identify the correlations between pathological severity and poor postoperative outcome in the Chinese population. METHODS: Between May 2006 and April 2011, 367 consecutive patients who underwent surgery for CAA-related ICH in 71 hospitals throughout the mainland of China were enrolled in this study. Twelve months after surgery, we evaluated these patients' outcomes according to the modified Rankin Scale (mRS) and statistically correlated risk factors (demographics, medical history, pathological results, and surgical details) that are associated with a favorable (mRS < 3) and poor (mRS ≥ 3) outcome groups. RESULTS: Risk factors for poor postoperative outcome in 367 patients with CAA-related ICH included advanced age (OR 1.034, 95%CI 1.001 - 1.067, P = 0.042), CAA pathology severity (OR 2.074, 95%CI 7.140 - 16.25, P < 0.001), lobar hematoma (OR 0.225, 95%CI 0.104 - 0.486, P < 0.001), presence of intraventricular hemorrhage (OR 0.478, 95%CI 0.229 - 1.001, P = 0.050), and/or subarachnoid hemorrhage (OR 2.629, 95%CI, 1.051 - 6.577, P = 0.039). CONCLUSIONS: Poor postoperative outcome of patients with CAA-related ICH was more related to the severe pathological manifestation instead of other factors. Prior ischemia may present an early stage of CAA.


Assuntos
Angiopatia Amiloide Cerebral/patologia , Hemorragias Intracranianas/patologia , Idoso , Angiopatia Amiloide Cerebral/fisiopatologia , China , Feminino , Humanos , Hemorragias Intracranianas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco
19.
Chin Med J (Engl) ; 125(6): 1104-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22613538

RESUMO

BACKGROUND: Biofilms have given new insights to the understanding of pathogenesis of chronic rhinosinusitis (CRS). However, the link between biofilms formation and local inflammatory response remains poorly defined in CRS with nasal polys. The aim of this study was to determine the potential association of the presence of biofilms in the nasal mucosal tissues with clinical features in Chinese patients, which had CRS with nasal polyps (CRSwNP). METHODS: A total of 19 patients with CRSwNP and 12 patients with non-CRS were subjected to endoscopic surgery and their nasal mucosal tissue specimens were examined histologically and by scanning electron microscopy (SEM). Their demographic and clinical features were recorded. RESULTS: Thirteen (68.4%) out of the 19 specimens from patients with CRSwNP, but none from control patients, were positive for biofilms that displayed typical characteristics of bacterial and fugal structures. The presence of biofilms in the nasal mucosal tissues was associated with significantly greater values of purulent nasal discharge and preoperative Lund-Kennedy scores, higher levels of serum total IgE and percentages of subjects with endoscopic surgery (ESS) history in patients with CRSwNP, and more severe inflammation in the nasal mucosal tissues of patients with CRSwNP. CONCLUSION: Our study demonstrated the presence of biofilms in the nasal mucosal tissues of many patients, contributing to the understanding of the pathogenic process of CRSwNP in Chinese patients.


Assuntos
Biofilmes , Pólipos Nasais/etiologia , Rinite/etiologia , Sinusite/etiologia , Adolescente , Adulto , Doença Crônica , Feminino , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Mucosa Nasal/patologia , Pólipos Nasais/microbiologia , Pólipos Nasais/patologia , Rinite/microbiologia , Rinite/patologia , Sinusite/microbiologia , Sinusite/patologia
20.
Zhonghua Yi Xue Za Zhi ; 90(15): 1016-9, 2010 Apr 20.
Artigo em Chinês | MEDLINE | ID: mdl-20646517

RESUMO

OBJECTIVE: To get the general situation of the cerebral amyloid angiopathy (CAA) incidence in spontaneous intracranial hemorrhage (SICH) patients receiving surgical treatment in Chinese people. METHODS: During the period May 2008 and March 2009, 105 patients admitted to 30 hospitals throughout China for acute SICH were studied, including 68 male and 37 female mean aged (55 +/- 13). The patients were suffered from SICH proved by computed tomography scan (CT). Emergent craniotomies for hemorrhage evacuation were performed for these patients within 72 h after hemorrhage onset and brain tissue of the cortex was also obtained meanwhile. A further histological study, Congo red stained and Abeta immunochemistry included was followed to verify the existence of CAA. RESULT: Fifteen out of the 105 cases is identified as CAA positive, and the total ratio is 14.29%. As to age groups, about 20.83% (5/24) of the cases of the 40-49 years old group have been diagnosed as CAA, 17.14% (6/35) of the 50-59 years old group, 4.17% (1/24) of the 60-69 group, and for those older than 70 years, the ratio is 8.00% (2/25). CONCLUSION: We come to the conclusion that 14.29% of the surgically treated SICH events might be closely related to CAA.


Assuntos
Angiopatia Amiloide Cerebral/complicações , Hemorragias Intracranianas/etiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Angiopatia Amiloide Cerebral/cirurgia , Feminino , Humanos , Hemorragias Intracranianas/cirurgia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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