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1.
Invest Ophthalmol Vis Sci ; 64(15): 34, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38133502

RESUMO

Purpose: To evaluate the influencing factors of parapapillary ßBM and γ zones incidence in young adolescents and to explore their associations with axial length progression. Methods: In this prospective cohort study, 976 seventh-grade students from nine secondary schools in Beijing, China, were enrolled and followed up 1 year later. Parapapillary ßBM zone was defined as retinal pigment epithelium loss while Bruch's membrane was present. Parapapillary γ zone was defined as the absence of retinal pigment epithelium and Bruch's membrane. Logistic regression model was used to analyze the influencing factors of ßBM and γ zone incidence. A linear mixed model was used to analyze the associations between parapapillary zones and axial elongation. Results: Of the 976 participants, 139 (14.2%) had only ßBM zone, 398 (40.8%) had only γ zone, and 171 (17.5%) had both. At follow-up, the incidence of ßBM zone was 11.5% (76/659), and the incidence of γ zone was 9.7% (39/404). Optic disc tilt, thinner subfoveal choroid, and longer axial length at baseline showed a higher risk of γ zone incidence. The absence of γ zone at baseline showed a faster axial length progression. When the baseline axial length was 25 mm or longer, the ßBM zone was also related to the axial elongation. Conclusions: The γ zone was associated with axial length progression, and the ßBM zone was also associated with the axial length progression when the axial length exceeded 25 mm, which was consistent with the notion that excessive axial length growth not only is the extension of the eyeball but also has its own pathologic changes.


Assuntos
Disco Óptico , Humanos , Adolescente , Disco Óptico/patologia , Tomografia de Coerência Óptica/métodos , Estudos Prospectivos , Comprimento Axial do Olho/patologia , Corioide
2.
Animals (Basel) ; 13(22)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38003063

RESUMO

(1) Background: Two-dimensional shear wave elastography (2D-SWE) is a non-invasive method widely used in human medicine to assess the extent of liver fibrosis but only rarely applied to veterinary medicine. This study aimed to measure liver stiffness in healthy dogs and investigate the factors that impacted 2D-SWE measurement. (2) Methods: In total, 55 healthy dogs were enrolled and subjected to 2D-SWE measurements before and after anesthesia administration. Post-anesthesia 2D-SWE measurements and computerized tomography (CT) scans were obtained. (3) Results: The liver stiffness range in healthy dogs was 3.96 ± 0.53 kPa. In a stratified analysis based on confounding factors, liver stiffness was influenced by measurement site and anesthesia, but not by sex. No correlation was observed between liver stiffness and weight or liver CT attenuation. (4) Conclusions: 2D-SWE is feasible for liver stiffness measurement in dogs. Anesthesia and measurement site are sources of variability. Therefore, these factors should be considered while recording 2D-SWE measurements. Our data on liver stiffness in healthy dogs can serve as the basis for future studies on 2D-SWE to assess pathological conditions in dogs.

3.
Sensors (Basel) ; 23(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37571476

RESUMO

Finding ways to enable seamless communication between deaf and able-bodied individuals has been a challenging and pressing issue. This paper proposes a solution to this problem by designing a low-cost data glove that utilizes multiple inertial sensors with the purpose of achieving efficient and accurate sign language recognition. In this study, four machine learning models-decision tree (DT), support vector machine (SVM), K-nearest neighbor method (KNN), and random forest (RF)-were employed to recognize 20 different types of dynamic sign language data used by deaf individuals. Additionally, a proposed attention-based mechanism of long and short-term memory neural networks (Attention-BiLSTM) was utilized in the process. Furthermore, this study verifies the impact of the number and position of data glove nodes on the accuracy of recognizing complex dynamic sign language. Finally, the proposed method is compared with existing state-of-the-art algorithms using nine public datasets. The results indicate that both the Attention-BiLSTM and RF algorithms have the highest performance in recognizing the twenty dynamic sign language gestures, with an accuracy of 98.85% and 97.58%, respectively. This provides evidence for the feasibility of our proposed data glove and recognition methods. This study may serve as a valuable reference for the development of wearable sign language recognition devices and promote easier communication between deaf and able-bodied individuals.


Assuntos
Língua de Sinais , Dispositivos Eletrônicos Vestíveis , Humanos , Fala , Algoritmos , Audição
4.
Cell Death Dis ; 14(4): 269, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37059730

RESUMO

Hypoxia contributes to the initiation and progression of glioblastoma by regulating a cohort of genes called hypoxia-regulated genes (HRGs) which form a complex molecular interacting network (HRG-MINW). Transcription factors (TFs) often play central roles for MINW. The key TFs for hypoxia induced reactions were explored using proteomic analysis to identify a set of hypoxia-regulated proteins (HRPs) in GBM cells. Next, systematic TF analysis identified CEBPD as a top TF that regulates the greatest number of HRPs and HRGs. Clinical sample and public database analysis revealed that CEBPD is significantly up-regulated in GBM, high levels of CEBPD predict poor prognosis. In addition, CEBPD is highly expressed in hypoxic condition both in GBM tissue and cell lines. For molecular mechanisms, HIF1α and HIF2α can activate the CEBPD promotor. In vitro and in vivo experiments demonstrated that CEBPD knockdown impaired the invasion and growth capacity of GBM cells, especially in hypoxia condition. Next, proteomic analysis identified that CEBPD target proteins are mainly involved in the EGFR/PI3K pathway and extracellular matrix (ECM) functions. WB assays revealed that CEBPD significantly positively regulated EGFR/PI3K pathway. Chromatin immunoprecipitation (ChIP) qPCR/Seq analysis and Luciferase reporter assay demonstrated that CEBPD binds and activates the promotor of a key ECM protein FN1 (fibronectin). In addition, the interactions of FN1 and its integrin receptors are necessary for CEBPD-induced EGFR/PI3K activation by promoting EGFR phosphorylation. Furthermore, GBM sample analysis in the database corroborated that CEBPD is positively correlated with the pathway activities of EGFR/PI3K and HIF1α, especially in highly hypoxic samples. At last, HRPs are also enriched in ECM proteins, indicating that ECM activities are important components of hypoxia induced responses in GBM. In conclusion, CEPBD plays important regulatory roles in the GBM HRG-MINW as a key TF, which activates the EGFR/PI3K pathway through ECM, especially FN1, mediated EGFR phosphorylation.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/genética , Glioblastoma/metabolismo , Transdução de Sinais , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fatores de Transcrição , Proteômica , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Hipóxia/genética , Hipóxia/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Matriz Extracelular/metabolismo , Proteína delta de Ligação ao Facilitador CCAAT/metabolismo
5.
Accid Anal Prev ; 146: 105730, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32835953

RESUMO

How crashes translate into physical injuries remains controversial. Previous studies recommended a predictor, Delta-V, to describe the crash consequences in terms of mass and impact speed of vehicles in crashes. This study adopts a new factor, energy loss-based vehicular injury severity (ELVIS), to explain the effects of the energy absorption of two vehicles in a collision. This calibrated variable, which is fitted with regression-based and machine learning models, is compared with the widely-used Delta-V predictor. A multivariate ordered logistic regression with multiple classes is then estimated. The results align with the observation that heavy vehicles are more likely to have inherent protection and rigid structures, especially in the side direction, and so suffer less impact.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Escala de Gravidade do Ferimento , Veículos Automotores/classificação , Ferimentos e Lesões/etiologia , Humanos , Modelos Logísticos , Aprendizado de Máquina , Ferimentos e Lesões/epidemiologia
6.
Sci Total Environ ; 662: 530-536, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30699373

RESUMO

Heating processes for the removal of electronic components from waste printed circuit boards (WPCBs) is an important step in the chain of electronic waste recycling, and toxic fumes are generated during the de-soldering process, causing environmental pollution and posing health risks for the workers. This study is aimed to characterize emission and deposition fluxes of respirable particulate matter (PM), and assess exposure of workers to particle-bound polybrominated diphenyl ethers (PBDEs). An electrical low-pressure impactor was used to measure the real-time PM concentrations inside and outside the hood during the WPCBs de-soldering process. The results show that PM mass concentration inside the hood (204 mg/m3) was significantly higher than outside the hood (9.4 mg/m3), representing 95.4% PM removal by the hood. According to the International Commission on Radiological Protection model, the total deposition fluxes of PM in head airways region, tracheobronchial region, and alveolar region were determined as 1930, 74.0, and 123 µg/h, respectively. The deposition flux for coarse particles (2.5-10 µm) in the head airways was the largest (1830 µg/h), accounting for 86.1% of total PM deposited in respiratory system. The ∑8PBDEs concentration in PM10 inside the WPCBs de-soldering workshop was 20,300 pg/m3, and the ∑8PBDEs inhalation exposure for the worker was 1.46 ng/kg/day. This study improves understanding of PM emission mechanisms and provides fundamental data for health assessments during WPCBs de-soldering process.

7.
The Journal of Practical Medicine ; (24): 3074-3077, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-661362

RESUMO

Objective To evaluated the relationship of ambulatory pulse pressure and severity intracranial arterial stenosis. Methods 165 ischemic stroke patients with intracranial arterial stenosis were selected as stenosis group. And 142 patients with no obvious intracranial arterial stenosis were selected as control group. All patients were given ambulatory blood pressure monitoring. 24 h average systolic pressure ,diastolic pressure and ambulatory pulse pressure were measured. Results Ambulatory pulse pressure of stenosis group[(73.02 ± 10.86)mmHg]was significantly higher than that of control group[(59.63±12.96)mmHg,P<0.01]. Ambulatory pulse pressure of mod-erated stenosis group[(69.73±9.3)mmHg,P < 0.05]was significantly higher than that of control group[(59.63± 12.96)mmHg,P<0.01]. Ambulatory pulse pressure of severe stenosis group[(77.36±7.94)mmHg]was signifi-cantly higher than that of moderate stenosis group[(69.73±9.3)mmHg,P < 0.05]. The level of ambulatory pulse pressure was independent risk factors of intracranial arterial stenosis(OR value:1.092). Conclusions Ambulatory pulse pressure is significantly related to the severity of intracranial arterial stenosis and is an independent risk factor for intracranial arterial stenosis.

8.
The Journal of Practical Medicine ; (24): 3074-3077, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-658443

RESUMO

Objective To evaluated the relationship of ambulatory pulse pressure and severity intracranial arterial stenosis. Methods 165 ischemic stroke patients with intracranial arterial stenosis were selected as stenosis group. And 142 patients with no obvious intracranial arterial stenosis were selected as control group. All patients were given ambulatory blood pressure monitoring. 24 h average systolic pressure ,diastolic pressure and ambulatory pulse pressure were measured. Results Ambulatory pulse pressure of stenosis group[(73.02 ± 10.86)mmHg]was significantly higher than that of control group[(59.63±12.96)mmHg,P<0.01]. Ambulatory pulse pressure of mod-erated stenosis group[(69.73±9.3)mmHg,P < 0.05]was significantly higher than that of control group[(59.63± 12.96)mmHg,P<0.01]. Ambulatory pulse pressure of severe stenosis group[(77.36±7.94)mmHg]was signifi-cantly higher than that of moderate stenosis group[(69.73±9.3)mmHg,P < 0.05]. The level of ambulatory pulse pressure was independent risk factors of intracranial arterial stenosis(OR value:1.092). Conclusions Ambulatory pulse pressure is significantly related to the severity of intracranial arterial stenosis and is an independent risk factor for intracranial arterial stenosis.

9.
Zhonghua Yan Ke Za Zhi ; 45(12): 1105-10, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20193434

RESUMO

OBJECTIVE: To determine the effects of Heparin II (Hep II) domain on cultured human trabecular meshwork (HTM) cells. METHODS: HTM cells were cultured and treated with Hep II domain for 18 and 24 h. The morphological changes in HTM cells were assessed by light and electron microscopy. Changes in cell morphology and the organization of actin cytoskeleton, Vinculin, beta-Catenin were assessed by using immunofluorescence. RESULTS: Treatment of Hep II domains resulted in morphological changes from 10 to 24 h. In light microscopy, cells rounded up, retracted and detached from each other. In high performance liquid chromatography, Hep II domains-treated cells showed that actin fibre bundles were highly concentrated at the periphery of the cells with few actin filaments left in this area; decreased vinculin staining was observed toward the cell periphery; decreased beta-Catenin staining was also observed around the cell sub-membrane. Transmission electron microscopy showed expended intercellular space. After 24 h, changes of HTM cells were recovered. CONCLUSIONS: Hep II domains reversibly blocks actin cytoskeleton and cell-junction of HTM cells. Disorganization of actin cytoskeleton and cell-junction in trabecular meshwork through signal transduction may be a useful strategy for the decrease of intraocular pressure.


Assuntos
Fibronectinas/farmacologia , Heparina/farmacologia , Malha Trabecular/citologia , Malha Trabecular/efeitos dos fármacos , Actinas/metabolismo , Técnicas de Cultura de Células , Células Cultivadas , Humanos , Junções Intercelulares/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia
10.
Anal Chem ; 79(5): 1825-32, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17263513

RESUMO

The internal energy of neutral gas-phase organic and biomolecules, evaporated by means of laser-induced acoustic desorption (LIAD) into a Fourier transform ion cyclotron resonance mass spectrometer, was investigated through several experimental approaches. The desorbed molecules were demonstrated not to undergo degradation during the desorption process by collecting LIAD-evaporated molecules and subjecting them to analysis by electrospray ionization/quadrupole ion trap mass spectrometry. Previously established gas-phase basicity values were remeasured for LIAD-evaporated organic molecules and biomolecules with the use of the bracketing method. No endothermic reactions were observed. The remeasured basicity values are in close agreement with the values reported in the literature. The amount of internal energy deposited during LIAD is concluded to be less than a few kilocalories per mole. Chemical ionization with a series of proton-transfer reagents was employed to obtain a breakdown curve for a protonated dipeptide, Val-Pro, evaporated by LIAD. Comparison of this breakdown curve with a previously published analogous curve obtained by using substrate-assisted laser desorption (SALD) to evaporate the peptide suggests that the molecules evaporated via LIAD have a similar internal energy as those evaporated via SALD.


Assuntos
Ciclotrons , Lasers , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Termodinâmica , Acústica , Adenina/química , Análise de Fourier , Oligonucleotídeos/química , Volatilização
11.
J Am Chem Soc ; 127(37): 12758-9, 2005 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-16159243

RESUMO

Laser-induced acoustic desorption combined with mass spectrometry has been used to demonstrate that phenyl radicals can attack dinucleoside phosphates at both the sugar and base moieties, that purine bases are more susceptible to the attack than pyrimidine bases, and that the more electrophilic the radical, the more efficient the damage to dinucleoside phosphates.


Assuntos
Derivados de Benzeno/química , Fosfatos de Dinucleosídeos/química , Nucleotídeos de Purina/química , Purinas/química , Derivados de Benzeno/síntese química , Derivados de Benzeno/efeitos da radiação , Fosfatos de Dinucleosídeos/síntese química , Fosfatos de Dinucleosídeos/efeitos da radiação , Radicais Livres/química , Lasers , Espectrometria de Massas , Estrutura Molecular , Nucleotídeos de Purina/efeitos da radiação , Purinas/efeitos da radiação
12.
Eur J Pharmacol ; 472(3): 179-87, 2003 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-12871752

RESUMO

We have recently observed that increasing central noradrenergic transmission and sympathomimetic activity is involved with the complex hemodynamic effects during tolerance to nitroglycerin. The present study was to examine the release of nitric oxide (NO) in the posterior hypothalamus during tolerance to depressor responses to nitroglycerin and determine if, during the tolerance, endogenous NO synthesis is induced in the posterior hypothalamus. A microdialysis probe was implanted in the posterior hypothalamus and perfusion fluid was pumped through the probe at 2 microl/min in conscious rats. Tolerance to nitroglycerin was produced by three intravenous (i.v.) injections of 1.3 mg nitroglycerin each within 40 min compared to the same administrations of low dose of the drug, sodium nitroprusside and papaverine. Dialysate samples were collected 1 h before and 1 h each after injections for 8 h. Concentrations of nitrite (NO(2)(-)), nitrate (NO(3)(-)), and total nitrite plus nitrate (NO(x)(-)) were quantified in the samples by using chemiluminescence. The dose-response curve for arterial depressor induced by intravenous injection of the challenge doses of nitroglycerin was markedly shifted to the right at the first hour after nitroglycerin tolerance, lasted 3 to 5 h and reversed at 7 h. The dialysate NO(3)(-) and NO(x)(-) concentrations in the posterior hypothalamus were significantly increased at the first hour following nitroglycerin tolerance but were not altered by low dose of the drug, sodium nitroprusside, and papaverine. Nitroglycerin tolerance predominantly caused an increase in NO(3)(-) release in the posterior hypothalamus with no or small amount of changes in dialysate NO(2)(-) and the response was partially inhibited by pretreatment with N(G)-Propyl-L-arginine (NPLA) (1.0 mg/kg, i.p.), an inhibitor of neuronal NO synthesis. The increase of NO release in the posterior hypothalamus occurred at the first hour, lasted 2 to 3 h and reversed at 5 to 6 h during nitroglycerin tolerance. The results show that systemically administered high dose of nitroglycerin increases NO release in the posterior hypothalamus which matches the time interval of tolerance to arterial depressor response to the drug. Data suggest that there is an enhanced endogenous NO synthesis in the posterior hypothalamus which may affect central sympathetic functions during nitroglycerin tolerance.


Assuntos
Hipotálamo Posterior/efeitos dos fármacos , Hipotálamo Posterior/metabolismo , Óxido Nítrico/biossíntese , Nitroglicerina/farmacologia , Animais , Relação Dose-Resposta a Droga , Tolerância a Medicamentos/fisiologia , Masculino , Óxido Nítrico/metabolismo , Ratos , Ratos Sprague-Dawley
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