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1.
Med Sci Monit ; 24: 1366-1372, 2018 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-29508843

RESUMO

BACKGROUND Cardiac device infection (CDI) is a serious complication of cardiovascular implantable electronic device (CIED) implantations. Many risk factors have been identified, but several are still uncertain. This study aimed to identify and evaluate the risk factors. Moreover, an infection control protocol (ICP) was carried out, and its efficacy in reducing CDIs was investigated. MATERIAL AND METHODS A total of 1259 patients who received permanent pacemaker (PPM) implantations were enrolled in this study in a 3-year period in a high-volume center and low-volume centers in the central area of Shaanxi Province, China. Follow-up data of all enrolled patients were collected. The risk factors for CDIs were identified and analyzed. The ICP was adopted in the low-volume centers. Data, including CDI rates, medical costs, and microbiology, were collected and compared. RESULTS Male gender, diabetes, CKD, operation duration, PPM replacement, and low center volume were identified as the risk factors for CDIs. Furthermore, CDI rates in low-volume centers were significantly higher than in high-volume centers. The adoption of an ICP dramatically reduced CDI rates in low-volume centers without significant increases in medical costs. CONCLUSIONS ICPs were easily carried out, effective, and economical in controlling CDIs in low-volume centers, which was identified as a risk factor of CDIs.


Assuntos
Desfibriladores Implantáveis/efeitos adversos , Controle de Infecções/métodos , Marca-Passo Artificial/efeitos adversos , Idoso , China , Feminino , Cardiopatias , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/microbiologia , Fatores de Risco
2.
Nano Lett ; 16(2): 877-82, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26789719

RESUMO

We describe the controlled growth of planar InAsSb nanowires (NWs) on differently oriented Si substrates without any foreign catalysts. Interestingly, the planar InAsSb NWs grew along four criss-crossed ⟨110⟩ directions on an [100]-oriented substrate, two ⟨100⟩ directions plus four ⟨111⟩ directions on an [110]-oriented substrate, and six equivalent ⟨112⟩ directions on an [111]-oriented substrate, which correspond to the projections of ⟨111⟩ family crystal directions on the substrate planes. High-resolution transmission electron microscopy (HRTEM) reveals that the NWs experienced a transition from out-of-plane to in-plane growth at the early growth stage but still occurred on the {111} plane, which has the lowest surface energy among all the surfaces. Furthermore, the NWs exhibit a pure zinc-blende crystal structure without any defects. A growth model is presented to explain growth of the NWs. In addition, conductive atomic force microscopy shows that electrically rectifying p-n junctions form naturally between the planar InAsSb NWs and the p-type Si substrates. The results presented here could open up a new route way to fabricate highly integrated III-V nanodevices.

3.
Nanotechnology ; 27(27): 275601, 2016 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-27232079

RESUMO

We report the growth of InAs/GaSb core-shell heterostructure nanowires with smooth sidewalls on Si substrates using metal-organic chemical vapor deposition with no assistance from foreign catalysts. Sb adatoms were observed to strongly influence the morphology of the GaSb shell. In particular, Ga droplets form on the nanowire tips when a relatively low TMSb flow rate is used, whereas the droplets are missing and the radial growth of the GaSb is enhanced due to a reduction in the diffusion length of the Ga adatoms when the TMSb flow rate is increased. Moreover, transmission electron microscopy measurements revealed that the GaSb shell coherently grew on the InAs core. The results obtained here show that the InAs/GaSb core-shell nanowires grown using the Si platform have strong potential in the fabrication of future nanometer-scale devices and in the study of fundamental quantum physics.

4.
Nat Commun ; 15(1): 1773, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413622

RESUMO

Ultra-compact spectrometers are becoming increasingly popular for their promising applications in biomedical analysis, environmental monitoring, and food safety. In this work, we report a single-pixel-photodetector spectrometer with a spectral range from 480 nm to 820 nm, based on the AlGaAs/GaAs p-graded-n junction with a voltage-tunable optical response. To reconstruct the optical spectrum, we propose a tailored method called Neural Spectral Fields (NSF) that leverages the unique wavelength and bias-dependent responsivity matrix. Our spectrometer achieves a high spectral wavelength accuracy of up to 0.30 nm and a spectral resolution of up to 10 nm. Additionally, we demonstrate the high spectral imaging performance of the device. The compatibility of our demonstration with the standard III-V process greatly accelerates the commercialization of miniaturized spectrometers.

5.
World J Clin Cases ; 11(3): 692-699, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36793647

RESUMO

BACKGROUND: Hemangioblastoma typically occurs in the cerebellum, spinal cord, and central nervous system. However, in rare cases, it could occur in the retina or optic nerve. The prevalence of retinal hemangioblastoma is 1 in 73080, and it occurs either alone or as the manifestation of von Hippel Lindau (VHL) disease. Here, we reported a rare case with the imaging features of retinal hemangioblastoma without VHL syndrome, along with the relevant literature review. CASE SUMMARY: A 53-year-old man had progressive swelling, pain and blurred vision in the left eye without obvious inducement for 15 d. Ultrasonography revealed a possible optic nerve head melanoma. Computed tomography (CT) showed punctate calcification on the posterior wall of the left eye ring and small patchy soft tissue density in the posterior part of the eyeball. Magnetic resonance imaging showed slightly hyperintense signal on T1-weighted images and slightly hypointense-to-isointense signal on T2-weighted images at the medial and posterior edges of the left eyeball, a significant enhancement was observed in the contrast-enhanced scans. Positron emission tomography/CT fusion images showed that the glucose metabolism of the lesion was normal. Pathology was consistent with hemangioblastoma. CONCLUSION: Early identification of retinal hemangioblastoma based on imaging features is of great value for its personalized treatment.

6.
Opt Lett ; 37(19): 4071-3, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23027282

RESUMO

We demonstrate high-brightness 1.3 µm tapered lasers with high temperature stability by using p-doped InAs/GaAs quantum dots (QDs) as the active region. It is found that the beam quality factor M(2) for the devices is almost unchanged as the light power and temperature increase. The almost constant M(2) results from the p-doped QD active region.


Assuntos
Arsenicais/química , Gálio/química , Índio/química , Lasers , Pontos Quânticos , Temperatura
7.
Opt Lett ; 37(8): 1298-300, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22513665

RESUMO

The carrier induced refractive index change and linewidth enhancement factor α due to ground-state (GS) and excited-state (ES) transitions have been compared by measuring the optical gain spectra from an InAs/GaAs quantum dot (QD) laser structure. It is shown that the ES transition exhibits a reduced α-factor compared to the value due to the GS transition. This result can be explained by the α-factor due to the ES transition having a smaller increase from the non-resonant carriers in the combined state of the wetting layer and InGaAs strain reducing layer than the α-factor increase due to the GS transition, since the relaxation time for carriers from the combined state of the wetting layer and InGaAs strain reducing layer to the ES is shorter than to the GS. The result reported here shows another advantage of using ES QD lasers for optical communication, in addition to their higher modulation speed.

8.
Front Oncol ; 12: 824509, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35530350

RESUMO

Objective: We aimed to establish an MRI radiomics model and a Delta radiomics model to predict tumor retraction after induction chemotherapy (IC) combined with concurrent chemoradiotherapy (CCRT) for primary nasopharyngeal carcinoma (NPC) in non-endemic areas and to validate its efficacy. Methods: A total of 272 patients (155 in the training set, 66 in the internal validation set, and 51 in the external validation set) with biopsy pathologically confirmed primary NPC who were screened for pretreatment MRI were retrospectively collected. The NPC tumor was delineated as a region of interest in the two sequenced images of MRI before treatment and after IC, followed by radiomics feature extraction. With the use of maximum relevance minimum redundancy (mRMR) and least absolute shrinkage and selection operator (LASSO) algorithms, logistic regression was performed to establish pretreatment MRI radiomics and pre- and post-IC Delta radiomics models. The optimal Youden's index was taken; the receiver operating characteristic (ROC) curve, calibration curve, and decision curve were drawn to evaluate the predictive efficacy of different models. Results: Seven optimal feature subsets were selected from the pretreatment MRI radiomics model, and twelve optimal subsets were selected from the Delta radiomics model. The area under the ROC curve, accuracy, sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of the MRI radiomics model were 0.865, 0.827, 0.837, 0.813, 0.776, and 0.865, respectively; the corresponding indicators of the Delta radiomics model were 0.941, 0.883, 0.793, 0.968, 0.833, and 0.958, respectively. Conclusion: The pretreatment MRI radiomics model and pre- and post-IC Delta radiomics models could predict the IC-CCRT response of NPC in non-epidemic areas.

9.
J Nanosci Nanotechnol ; 11(11): 9345-56, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22413215

RESUMO

Self-assembled In(Ga)As/GaAs quantum dots (QDs), known as "artificial atoms" for their fully quantized electronic states, show unique physical properties and new prospects for applications. Based on the QDs, an increasing number of leading laboratories on the world engage in developing novel optoelectronic devices with special advantages over existing devices. This paper reviews the current research developments in self-assembled QD devices in China, covering QD lasers and inter sub-level QD photodetectors. QD devices in China are undergoing a rapid advance and have achieved the world's best results in terms of certain characteristics.

10.
Pathol Oncol Res ; 24(4): 853-860, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28887636

RESUMO

To investigate the repression of miR-184 on Stanniocalcin-2 (STC2) and how this axis affects the propagation, invasiveness and migration ability of glioblastoma cells. RT-PCR was employed to determine the miR-184 and STC2 mRNA expression both in tissues and cells. Western blot was employed to determine the protein expression levels. The cells were transfected via lipofection. MTT, colony formation, invasion and scratch healing assays were conducted to study the propagation, invasiveness and migratory ability of glioblastoma cells, respectively. The dual luciferase reporter gene assay was conducted to determine whether miR-184 could directly bind to STC2 mRNA 3'UTR. MiR-184 was under-expressed whereas STC2 was over-expressed in glioblastoma tissues and cell line. The up-regulation of miR-184 significantly suppressed the propagation, migratory ability and invasion of glioblastoma cells, whereas the over-expression of STC2 restored this effect. MiR-184 was confirmed to directly target STC2. MiR-184 could retard the propagation, invasiveness and migratory ability of glioblastoma cells by suppressing STC2.


Assuntos
Neoplasias Encefálicas/patologia , Regulação Neoplásica da Expressão Gênica/genética , Glioblastoma/patologia , Glicoproteínas/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , MicroRNAs/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Glioblastoma/metabolismo , Glioblastoma/mortalidade , Glicoproteínas/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , MicroRNAs/genética , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Taxa de Sobrevida
11.
Biosci Rep ; 37(3)2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28336765

RESUMO

The present study intended to investigate the biological effects of miR-330-5p on glioblastoma (GBM) cell proliferation and invasiveness by targeting integrin α5 (ITGA5). The expressions of miR-330-5p and ITGA5 mRNA in GBM cell lines (U87, U251, and U373) and normal brain glial cell line (HEB) were detected using RT-qPCR. Protein expression of ITGA5 was examined using Western blot. The present study used MTT assay, colony formation assay, Transwell assay, wound healing assay, and flow cytometry analysis in order to determine the biological functions of GBM cells (including cell proliferation, invasion, migration, apoptosis, and cell cycle). The present study applied dual-luciferase reporter gene assay to identify the target relationship between miR-330-5p and ITGA5. miR-330-5p was low-expressed in GBM cell lines while ITGA5 was high-expressed compared with HEB. miR-330-5p could directly target ITGA5 as well as suppress its expression in GBM cells. Up-regulation of miR-330-5p and down-regulation of ITGA5 both have an inhibitory effect on cell proliferation, invasion, and migration. Meanwhile, they could also promote GBM cell apoptosis. miR-330-5p could suppress proliferation and invasion of GBM cells through targeting ITGA5.


Assuntos
Neoplasias Encefálicas/patologia , Genes Supressores de Tumor , Glioblastoma/patologia , Integrina alfa5/metabolismo , MicroRNAs/metabolismo , Apoptose , Neoplasias Encefálicas/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Humanos , Integrina alfa5/genética , MicroRNAs/genética , Invasividade Neoplásica , Regulação para Cima
12.
Eur J Pharmacol ; 627(1-3): 124-30, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-19913012

RESUMO

The aim of this study was to examine the involvement of 5-HT and 5-HT(2A) receptors in neuropathic pain and their possible cellular mechanism. To evaluate a potential therapy the 5-HT(2A) receptor antagonist ketanserin was administered topically or subcutaneously in rats with L5 nerve ligation. Unilateral spinal nerve ligation induced hypersensitivity to thermal and mechanical stimuli in the ipsilateral hindpaw and an increase in calcitonin gene-related peptide (CGRP) immunoreactivity (CGRP-IR) in small and medium diameter neurons in dorsal root ganglia (DRG) at L4 and L6, but not at L5. Topical application of ketanserin (3%) delivered in a mixture of gelatin, glycerol and kaolin onto skin over the hindpaw produced significant elevation of nociceptive threshold in the paw. Daily injection of ketanserin inhibited the thermal hyperalgesia in a dose dependent manner (0.1 and 0.3mg/kg, s.c.). The inhibition occurred at 1-3 days after the injection started and persisted for at least 2 weeks without decline. Injection of ketanserin (0.3mg/kg) also suppressed tactile allodynia. Moreover, ketanserin (0.3mg/kg) reversed the increase in CGRP-IR expression in L4 and L6 DRG neurons. These results support the hypothesis that adaptive change in CGRP expression that occurred in the DRG adjacent to the DRG containing injured neurons underlies the nerve ligation-induced hypersensitivity. This study suggests that 5-HT and 5-HT(2A) receptors contribute to the maintenance of neuropathic pain by up-regulating the expression of CGRP-IR, and that topical and systemic administrations of ketanserin are promising therapies for relieving neuropathic pain without tolerance.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Ketanserina/administração & dosagem , Ketanserina/farmacologia , Dor/tratamento farmacológico , Percepção/efeitos dos fármacos , Nervos Espinhais/cirurgia , Administração Tópica , Animais , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Gânglios Espinais/patologia , Hiperalgesia/etiologia , Hiperalgesia/metabolismo , Hiperalgesia/psicologia , Injeções Subcutâneas , Ketanserina/uso terapêutico , Ligadura , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Dor/etiologia , Dor/metabolismo , Dor/psicologia , Ratos , Ratos Sprague-Dawley , Receptores de Serotonina/metabolismo , Serotonina/metabolismo , Antagonistas da Serotonina/administração & dosagem , Antagonistas da Serotonina/farmacologia , Antagonistas da Serotonina/uso terapêutico , Nervos Espinhais/efeitos dos fármacos
13.
Pain ; 124(1-2): 27-33, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16647209

RESUMO

We investigated effects of topical application of ketanserin, a 5-HT2A receptor antagonist, on hyperalgesia and edema in the arthritic rat, a chronic pain model with inflammation. Unilateral, but not bilateral, arthritis was induced with intra-articular injection of a mixture of kaolin and carrageenan in one side, as indicated by the shortened paw withdrawal latency and an increase in the circumference of the knee joint. Topical application of ketanserin onto skin over the arthritic joint delivered in a mixture of gelatin, glycerol and kaolin produced dose-dependent attenuation of nociceptive and inflammatory effects resulting from intra-articularly injected kaolin/carrageenan. One and 3% ketanserin produced significant or even complete anti-hyperalgesia, as well as a remarkable anti-inflammatory effect (50-70% reduction of edema) while 0.3% ketanserin and placebo failed to produce any effect. Moreover, the effects of ketanserin were maintained for 13 days without decline. In contrast, 3% ketanserin applied to skin of the knee joint on the non-inflamed side for 2 weeks did not alter nociceptive thresholds of the paw and the size of the knee joint in both the inflamed and non-inflamed limbs. These results indicate that 5-HT2A receptors in the periphery play a significant role in the maintenance and/or development of inflammatory pain. The present study suggests that topical ketanserin is a promising direction for potential clinical exploration to relieve established hyperalgesia and inflammation in arthritis without adverse effects and tolerance.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Experimental/fisiopatologia , Hiperalgesia/tratamento farmacológico , Inflamação/tratamento farmacológico , Ketanserina/administração & dosagem , Antagonistas da Serotonina/administração & dosagem , Administração Tópica , Análise de Variância , Animais , Artrite Experimental/induzido quimicamente , Comportamento Animal , Carragenina , Hiperalgesia/etiologia , Inflamação/etiologia , Caulim , Extremidade Inferior/patologia , Masculino , Medição da Dor/métodos , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos
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