Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 172
Filtrar
1.
J Cancer Res Ther ; 18(2): 560-566, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35645128

RESUMO

Objective: To investigate the influencing factors of transcatheter arterial chemoembolization (TACE) on patients with hepatocellular carcinoma (HCC) for tumor response (complete and partial response, CR + PR). Methods: This research conducted a retrospective study of the hospital charts of patients treated with TACE successfully renewed from October 2014 to December 2015 at Sun Yat-sen University Cancer Center (Guangzhou, China). Univariate analysis (Chi-square test and repeated-measures ANOVA) selected nine influential tumor response factors from 22 core factors. The nine variables were included in a forward multiple logistic regression model predicting patients treated with TACE to achieve tumor response. Overall survival was calculated using the Kaplan-Meier method. Results: Data of 277 of 282 patients were included in the analysis. Nine variables were analyzed by univariate analysis and independently associated with tumor response (tumor capsule integrity, nausea and vomiting, microwave ablation, liver dysfunction, the absolute value of lymphocyte (LYM), alpha-fetoprotein, and gamma-glutamyl transpeptidase (GGT). By multivariate analysis, GGT (odds ratio [OR] =0.996), liver dysfunction (OR = 0.395), combined with microwave ablation (OR = 0.503), and tumor capsule integrity (OR = 1.894) were the significant predictors of the tumor response group compared with the standard deviation group (P < 0.05). Conclusions: This study suggests that TACE combined with ablation on patients with complete tumor capsules may have a better prognosis in tumor response and OS; additionally, liver dysfunction and nausea and vomiting were the independent predictors of tumor response.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Humanos , Neoplasias Hepáticas/terapia , Estudos Retrospectivos , Resultado do Tratamento
2.
Nanomaterials (Basel) ; 12(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35564232

RESUMO

Aqueous CdTe quantum dots solar cells have been successfully fabricated by the blade coating method on the magnesium zinc oxide (Zn1-xMgxO or ZMO) window layer. Compared with the ZMO mono-window layer, the ZMO/CdS bi-window layer can decrease the interface recombination effectively due to the lower lattice mismatch and fast interdiffusion between CdS and CdTe. Moreover, the high temperature annealing of the CdTe quantum dots absorbed layer passivates the grain boundary of the CdTe crystalline via the replacement reaction of tellurium with sulfur. Finally, the conversion efficiency of our aqueous CdTe quantum dots solar device is improved from 3.21% to 8.06% with the introduction of the CdS interlayer and high temperature CdCl2 annealing. Our aqueous CdTe quantum dots solar devices show a large open circuit voltage and fill factor which are comparable with the conventional devices that are fabricated with organic CdTe quantum dots. We believe that it is the spike-like conduction band alignment between the ZMO and CdTe absorbed layer that reduces the majority carrier concentration, leading to the decrease in interface recombination probability.

3.
Front Psychol ; 13: 860902, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35592176

RESUMO

Background: Nurses can experience psychological trauma after adverse nursing events, making it likely for them to become second victims (SVs). This negatively impacts patient safety and nurses' development. This study aims to understand the status of psychological trauma and recovery of nurses as SVs in domestic China and examine the influencing mechanism of cognitive rumination during their recovery from psychological damage. Methods: This was a cross-sectional survey. An online questionnaire was completed by 233 nurses from across China. Data were collected using Chinese versions of the Second Victim Experience and Support Evaluation Scale, the Incident-related Rumination Meditation Questionnaire, and the post-traumatic growth (PTG) Rating Scale. Descriptive statistics, correlation, and regression, as well as mediation analysis, were used for different analyses in this study. Results: Participants experienced apparent psychological traumas (4.65 ± 0.5583) with a certain degree of PTG (76.18 ± 16.0040); they reported a strong need for psychological support (95.7%). Psychological trauma was positively and negatively correlated with rumination and PTG (r = 0.465, p < 0.001; r = -0.155, p < 0.05) respectively. Both psychologically impaired experience and rumination had significant predictive effects on participants' PTG (both, p < 0.001). Nurses' active rumination significantly mediated their psychological recovery from trauma to PTG (p < 0.05), but the effect of invasive rumination was not significant (p > 0.05). Limitation: The specific manifestations of the mechanism of invasive rumination are not clarified in this study. Conclusion: The present study investigated the psychological trauma of SV nurses as well as their support needs, and explored the role of cognitive rumination in the psychological repair and PTG of SV nurses. Results showed that SV nurses' active rumination on adverse nursing events could promote their recovery from psychological trauma, but invasive rumination could not. This study provides a trauma-informed approach to care at the clinical level for nurses who experience psychological trauma caused by adverse events.

4.
Front Aging Neurosci ; 14: 904085, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35615596

RESUMO

We aimed to develop and validate an objective and easy-to-use model for identifying patients with spontaneous intracerebral hemorrhage (ICH) who have a poor 90-day prognosis. This three-center retrospective study included a large cohort of 1,122 patients with ICH who presented within 6 h of symptom onset [training cohort, n = 835; internal validation cohort, n = 201; external validation cohort (center 2 and 3), n = 86]. We collected the patients' baseline clinical, radiological, and laboratory data as well as the 90-day functional outcomes. Independent risk factors for prognosis were identified through univariate analysis and multivariate logistic regression analysis. A nomogram was developed to visualize the model results while a calibration curve was used to verify whether the predictive performance was satisfactorily consistent with the ideal curve. Finally, we used decision curves to assess the clinical utility of the model. At 90 days, 714 (63.6%) patients had a poor prognosis. Factors associated with prognosis included age, midline shift, intraventricular hemorrhage (IVH), subarachnoid hemorrhage (SAH), hypodensities, ICH volume, perihematomal edema (PHE) volume, temperature, systolic blood pressure, Glasgow Coma Scale (GCS) score, white blood cell (WBC), neutrophil, and neutrophil-lymphocyte ratio (NLR) (p < 0.05). Moreover, age, ICH volume, and GCS were identified as independent risk factors for prognosis. For identifying patients with poor prognosis, the model showed an area under the receiver operating characteristic curve of 0.874, 0.822, and 0.868 in the training cohort, internal validation, and external validation cohorts, respectively. The calibration curve revealed that the nomogram showed satisfactory calibration in the training and validation cohorts. Decision curve analysis showed the clinical utility of the nomogram. Taken together, the nomogram developed in this study could facilitate the individualized outcome prediction in patients with ICH.

5.
Front Microbiol ; 13: 830741, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464922

RESUMO

Background: The existence of hepatic cancer stem cells (CSCs) contributes to chemotherapy resistance and cancer recurrence after treatment or surgery. However, very little is known about the hepatitis B virus (HBV) replication and its relationship with the stemness of hepatocellular carcinoma (HCC) in HBV-related HCC patients. Methods: We collected tumor tissues (T), matched adjacent non-tumor tissues (NT), and distal non-tumor tissues (FNT) from 55 HCC patients for analysis. Results: We found HBV DNA levels were higher in T samples than NT and FNT samples, but HBV pgRNA and total RNA expressed lower in T samples. HBV pgRNA and total RNA correlate to HBV DNA among the T, NT, and FNT samples. Further evidence for HBV replication in T samples was provided by HBV S, reverse transcriptase, and X genes sequencing, showing that HBV sequences and genotypes differed between T and matched NT and FNT samples. HBV pgRNA and total RNA showed more frequent significant correlations with CSC markers in NT samples in HBsAg-positive patients. The markers CD133 and OCT4 expressed higher in FNT samples, and HBV replication marker of pgRNA levels was significantly positively correlated to these two markers only in FNT samples. The detection of pgRNA and OCT4 in FNT was correlated to the recurrence of HCC in the resection of HCC patients. Analysis of HBV receptor, sodium taurocholate co-transporting polypeptide (NTCP), showed that NTCP was correlated negatively to CSC markers in T samples, except for the CD44. Conclusion: HBV replication may present in HCC with a weak transcriptomic signature. Moreover, the expression level of HBV pgRNA in distal non-tumor tissues is a sensitive marker for HBV replication and prognosis, which is associated with CSC-related markers especially with OCT4 in distal non-tumor tissues and recurrence of HCC in HBV-related HCC patients.

6.
Insect Sci ; 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35276754

RESUMO

Secretory phospholipase A2s (sPLA2s) are found in a wide range of organisms from bacteria to higher plants and animals and are involved in varied and cellular processes. However, roles of these enzymes in microbial pathogens remain unclear. Here, an sPLA2 (BbPLA2) was characterized in the filamentous insect pathogenic fungus, Beauveria bassiana. BbPLA2 was exclusively expressed in insect hemolymph-derived cells (hyphal bodies), and its expression was induced by insect-derived nutrients and lipids, and nutrient starvation. High levels of secretion of BbPLA2 were observed as well as its distribution in hyphal body lipid drops (LDs). Overexpression of BbPLA2 increased the ability of B. bassiana to utilize insect-derived nutrients and lipids, and promoted LD accumulation, indicating functions for BbPLA2 in mediating LD homeostasis and assimilation of insect-derived lipids. Strains overexpressing BbPLA2 showed moderately increased virulence, including more efficient penetration of the insect cuticle and evasion of host immune responses as compared to the wild type strain. In addition, B. bassiana-activated host immune genes were downregulated in the BbPLA2 overexpression strain, but upregulated by infections with a ΔBbPLA2 strain. These data demonstrate that BbPLA2 contributes to LD homeostasis, assimilation of insect-derived lipids, and repression of host immune responses.

7.
Neurosurg Rev ; 45(3): 2449-2456, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35303202

RESUMO

This study aimed to investigate the value of apparent diffusion coefficient (ADC) histogram analysis in differentiating intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC) from atypical meningioma (ATM). Retrospective analyzed the clinical, magnetic resonance imaging, and pathological data of 20 and 25 patients with SFT/HPC and ATM, respectively. Histogram analysis was performed on the axial ADC images using MaZda software, and nine histogram parameters were obtained, including mean, variance, skewness, kurtosis, and the 1st (ADC1), 10th (ADC10), 50th (ADC50), 90th (ADC90), and 99th (ADC99) percentile ADC. Differences in ADC histogram parameters between SFT/HPC and ATM were compared by an independent t test or Mann-Whitney U test, while the statistically significant histogram parameters were further analyzed by drawing receiver operating characteristic (ROC) curves to evaluate the differential diagnostic performance. Among the nine ADC histogram parameters we extracted, the mean, ADC1, ADC10, ADC50, and ADC90 in the SFT/HPC group were greater than those of ATM, and significant differences were observed (all P < 0.05). ROC analysis showed that the ADC1 generated the highest area under the curve (AUC) value of 0.920 in distinguishing the two tumors, when using 91.00 as the optimal threshold. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value in distinguishing between SFT/HPC and ATM were 84.00%, 85.00%, 84.44%, 87.50%, and 81.00%, respectively. ADC histogram analysis can be a reliable tool to differentiate between SFT/HPC and ATM, with the ADC1 being the most promising potential parameter.


Assuntos
Hemangiopericitoma , Neoplasias Meníngeas , Meningioma , Tumores Fibrosos Solitários , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética/métodos , Hemangiopericitoma/diagnóstico por imagem , Hemangiopericitoma/cirurgia , Humanos , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Curva ROC , Estudos Retrospectivos , Tumores Fibrosos Solitários/diagnóstico por imagem , Tumores Fibrosos Solitários/cirurgia
9.
Opt Express ; 30(1): 377-388, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-35201215

RESUMO

Bidirectional nanoprinting, has received significant attention in image display and on-chip integration, due to its superior advantages. By manipulating the amplitude in a narrow- or broad-band wavelength range of forward and backward incident light, different spatially varied intensities or color distributions can be generated on the structure plane. However, the current scheme cannot fully decouple the bidirectional light intensity due to the limitation of design degree of freedom, and it would hinder the development of asymmetric photonic devices. In this paper, we propose and demonstrate bidirectional nanoprinting based on an all-dielectric bilayer metasurface, which can independently control the intensity of forward and backward incident light, resulting in two different continuous grayscale meta-image displaying in the visible region. This asymmetric but still bidirectional optical response is introduced by stacking two layers of nanostructures with different functionality in space, in which the first- and second-layer nanostructures act as a half-wave plate and a polarizer, respectively. Interestingly, these bidirectional nanoprinting metasurfaces have flexible working modes and may bring great convenience for practical applications. Specifically, two different meta-images generated by a bidirectional nanoprinting metasurface can be displayed not only on two sides of the metasurface (working mode in transmission or reflection), but on the same side due to the forward transmitted light and backward reflected light also having asymmetric optical properties. Similar phenomena also exist for forward reflected light and backward transmitted light. Our work extremely expands the design freedom for metasurface devices and may play a significant role in the field of optical display, information multiplexing, etc.

10.
Clin Neuroradiol ; 32(1): 269-276, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35029726

RESUMO

PURPOSE: To explore the value of an apparent diffusion coefficient (ADC) histogram in predicting the Ki-67 proliferation index in pituitary macroadenomas. MATERIAL AND METHODS: This retrospective study analyzed the pathological and imaging data of 102 patients with pathologically confirmed pituitary macroadenoma. Immunohistochemistry staining was used to assess Ki-67 expression in tumor tissue samples, and a high Ki-67 labeling index was defined as 3%. The ADC images of the maximum slice of tumors were selected and the region of interest (ROI) of each slice was delineated using the MaZda software (version 4.7, Technical University of Lodz, Institute of Electronics, Lódz, Poland) and analyzed by ADC histogram. Histogram characteristic parameters were compared between the high Ki-67 group (n = 42) and the low Ki-67 group (n = 60). The important parameters were further analyzed by receiver operating characteristic (ROC). RESULTS: The mean value, and the 1st, 10th, 50th, 90th, and 99th percentiles were found to be negatively correlated with Ki-67 expression (all P < 0.05), with correlation coefficients of -0.292, -0.352, -0.344, -0.289, -0.253 and -0.267, respectively. The mean ADC and the 1st, 10th, 50th, 90th, and 99th quantiles extracted from the histogram were significantly lower in the high Ki-67 group than in the low Ki-67 group (all P < 0.05). The area under the ROC curve was 0.699-0.720; however, there were no significant between-group differences in variance, skewness and kurtosis (all P > 0.05). CONCLUSION: An ADC histogram can be a reliable tool to predict the Ki-67 proliferation status in patients with pituitary macroadenomas.


Assuntos
Imagem de Difusão por Ressonância Magnética , Antígeno Ki-67/metabolismo , Neoplasias Hipofisárias , Imagem de Difusão por Ressonância Magnética/métodos , Humanos , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Curva ROC , Estudos Retrospectivos
11.
Neurosurg Rev ; 45(2): 1625-1633, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34761325

RESUMO

This study evaluated the value of the apparent diffusion coefficient (ADC) in distinguishing grade II and III intracranial solitary fibrous tumors/hemangiopericytomas and explored the correlation between ADC and Ki-67. The preoperative MRIs of 37 patients treated for solitary fibrous tumor/hemangiopericytoma (grade II, n = 15 and grade III, n = 22) in our hospital from 2011 to October 2020 were retrospectively analyzed. We compared the difference between the minimum, average, maximum, and relative ADCs based on tumor grade and examined the correlation between ADC and Ki-67. Receiver operating characteristic curve analysis was used to analyze the diagnostic efficiency of the ADC. There were significant differences in the average, minimum, and relative ADCs between grade II and III patients. The optimal cutoff value for the relative ADC value to differentiate grade II and III tumors was 0.998, which yielded an area under the curve of 0.879. The Ki-67 proliferation indexes of grade II and III tumors were significantly different, and the average (r = - 0.427), minimum (r = - 0.356), and relative (r = - 0.529) ADCs were significantly negatively correlated with the Ki-67 proliferation index. ADC can be used to differentiate grade II and III intracranial solitary fibrous tumors/hemangiopericytomas. Our results can be used to formulate a personalized surgical treatment plan before surgery.


Assuntos
Hemangiopericitoma , Tumores Fibrosos Solitários , Proliferação de Células , Imagem de Difusão por Ressonância Magnética/métodos , Hemangiopericitoma/diagnóstico por imagem , Hemangiopericitoma/cirurgia , Humanos , Antígeno Ki-67 , Estudos Retrospectivos , Tumores Fibrosos Solitários/diagnóstico por imagem , Tumores Fibrosos Solitários/cirurgia
12.
Neurosci Lett ; 770: 136397, 2022 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-34915100

RESUMO

Amyloid ß-peptide (Aß) is the driven force of Alzheimer's disease (AD), and reducing Aß production could be a potential therapeutic strategy for AD. sAPPα appears to have the ability to specifically inhibit ß-cleavage of APP without inhibiting BACE1 completely, direct administration of sAPPα may not be clinically applicable due to the low permeability of blood-brain barrier (BBB). In this study, we investigated the neuroprotective effects of a short peptide generated from sAPPα, which could specifically bind to BACE1 at the BACE1-APP action site. We found that this peptide significantly reduced Aß production both in vivo and in vitro, thus further attenuated Aß deposition, Tau hyperphosphorylation, neuroinflammation et al. and rescued behavioral deficits. Therefore, this short peptide may hold promise for the treatment of AD due to its neuroprotective effects, low molecular weight to cross BBB, and less safety concerns. The anti-neurodegenerative capacity of sAPPα may not result solely from direct inhibition of BACE1.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Inibidores de Proteases/uso terapêutico , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Peptídeos beta-Amiloides/química , Animais , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Sítios de Ligação , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Inibidores de Proteases/farmacologia , Ligação Proteica , Proteólise/efeitos dos fármacos
13.
iScience ; 24(12): 103510, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34917896

RESUMO

In metasurface-based ultra-compact image display, color-nanoprints, gray-imaging elements, and binary-pattern-imaging elements are three different types of nanoprints, implemented with different mechanisms of light manipulation. Here, we show the three functional elements can be integrated together to form a "three-in-one" nanoprint with negligible crosstalk, merely with a single-cell nanostructured design approach. Specifically, by decoupling spectrum and polarization-assisted intensity manipulations of incident light, the proposed metasurface appears as a dual-color nanoprint under a broadband unpolarized light source illumination, while simultaneously displaying an independent continuous gray image and another binary-pattern in an orthogonal-polarization optical setup with different polarization controls. Our approach can increase the system integration and security of metasurfaces, which can be of interest to many advanced applications such as data storage, optical information encoding, high-end optical anti-counterfeiting, and optical information hiding.

14.
Acta Radiol ; : 2841851211066757, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34923852

RESUMO

BACKGROUND: Preoperative prediction of postoperative tumor progression of intracranial grade II-III hemangiopericytoma is the basis for clinical treatment decisions. PURPOSE: To use preoperative magnetic resonance imaging (MRI) semantic features for predicting postoperative tumor progression in patients with intracranial grade II-III solitary fibrous tumor/hemangiopericytoma (SFT/HPC). MATERIAL AND METHODS: We retrospectively analyzed the preoperative MRI data of 42 patients with intracranial grade II-III SFT/HPC, as confirmed by surgical resection and pathology in our hospital from October 2010 to October 2017, who were followed up for evaluation of recurrence, metastasis, or death. We applied strict inclusion and exclusion criteria and finally included 37 patients. The follow-up time was in the range of 8-120 months (mean = 57.1 months). RESULTS: Single-factor survival analysis revealed that tumor grade (log-rank, P = 0.024), broad-based tumor attachment to the dura mater (log-rank, P = 0.009), a blurred tumor-brain interface (log-rank, P = 0.008), skull invasion (log-rank, P = 0.002), and the absence of postoperative radiotherapy (log-rank, P = 0.006) predicted postoperative intracranial SFT/HPC progression. Multivariate survival analysis revealed that tumor grade (P = 0.009; hazard ratio [HR] = 11.42; 95% confidence interval [CI] = 1.832-71.150), skull invasion (P = 0.014; HR = 5.72; 95% CI = 1.421-22.984), and the absence of postoperative radiotherapy (P = 0.001; HR = 0.05; 95% CI = 0.008-0.315) were independent predictors of postoperative intracranial SFT/HPC progression. CONCLUSION: Broad-based tumor attachment to the dura mater, skull invasion, and blurring of the tumor-brain interface can predict postoperative intracranial SFT/HPC progression.

15.
BMJ Open ; 11(12): e049869, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34921074

RESUMO

OBJECTIVES: To investigate the airway management equipment and clinical practice in emergency department wards in China, and to explore the factors that influenced the nurses' airway management practice. DESIGN: Cross-sectional study. SETTING: A nationwide survey covering the seven administrative regions of China (North China, Northeast China, East China, Central China, South China, Southwest China and Northwest China). PARTICIPANTS: The nurses had to be registered nurses who worked in adult emergency department wards of the selected hospitals. MEASURES: An online survey was designed, piloted and distributed to the members of the Emergency Medicine Committee of the Chinese Nursing Association, and the nurses from the members' hospitals were invited to participate. The questionnaire was used to determine nurses' clinical practice scores of airway management in emergency wards. RESULTS: Finally, we collected 995 valid questionnaires from 31 provinces and 143 districts in China. Among them, 361 (36.28%) nurses responded that their departments used open suction system (OSS) in clinical work, the major barrier for closed suction system (CSS) reported by 630 respondents (63.32%) was cost. Significant differences in all three scores were found in age, nursing experience years, technical title, airway management training experience and nursing specialist (all p<0.05). Correlations were found among airway management attitude, practice of sputum aspiration and practice of ventilator care bundles (r=0.655, r=0.543 and r=0.763, all p<0.001). CONCLUSIONS: Chinese emergency department managers need to identify better methods for assessing equipment availability in OSS. CSS can be a choice when costs, status of the individual patient and severity of disease are comprehensively considered. Emergency department nurses' scores of airway management practice were affected by demographic and job-related characteristics; regular training should be encouraged, and equipment and resources should be guaranteed to improve airway management quality and optimise patient outcomes.


Assuntos
Serviço Hospitalar de Emergência , Recursos Humanos de Enfermagem no Hospital , Adulto , Manuseio das Vias Aéreas , China , Estudos Transversais , Hospitais , Humanos , Inquéritos e Questionários
16.
Nanomaterials (Basel) ; 11(8)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34443863

RESUMO

Electromagnetically induced transparency (EIT) based on dielectric metamaterials has attracted attentions in recent years because of its functional manipulation of electromagnetic waves and high refractive index sensitivity, such as high transmission, sharp phase change, and large group delay, etc. In this paper, an active controlled EIT effect based on a graphene-dielectric hybrid metamaterial is proposed in the near infrared region. By changing the Fermi level of the top-covered graphene, a dynamic EIT effect with a high quality factor (Q-factor) is realized, which exhibits a tunable, slow, light performance with a maximum group index of 2500. Another intriguing characteristic of the EIT effect is its high refractive index sensitivity. In the graphene-covered metamaterial, the refractive index sensitivity is simulated as high as 411 nm/RIU and the figure-of-merit (FOM) is up to 159, which outperforms the metastructure without graphene. Therefore, the proposed graphene-covered dielectric metamaterial presents an active EIT effect in the near infrared region, which highlights its great application potential in deep optical switching, tunable slow light devices, and sensitive refractive index sensors, etc.

17.
Dis Model Mech ; 14(9)2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34437681

RESUMO

Aging is a multifaceted process regulated by multiple cellular pathways, including the proteostasis network. Pharmacological or genetic enhancement of the intracellular proteostasis network extends lifespan and prevents age-related diseases. However, how proteostasis is regulated in different tissues throughout the aging process remains unclear. Here, we show that Drosophila homologs of Cubilin- and Amnionless (dCubilin and dAMN, respectively)-mediated protein reabsorption (CAMPR) from hemolymph insect blood by nephrocytes modulate longevity through regulating proteostasis in muscle and brain tissues. We find that overexpression of dAMN receptor in nephrocytes extends lifespan, whereas nephrocyte-specific dCubilin or dAMN RNAi knockdown shortens lifespan. We also show that CAMPR in nephrocytes regulates proteostasis in hemolymph and improves healthspan. In addition, we show that enhanced CAMPR in nephrocytes slows down the aging process in muscle and brain by maintaining the proteostasis network in these tissues. Altogether, our work has revealed an inter-organ communication network across nephrocytes and muscle/neuronal tissue that is essential for maintaining proteostasis, and to delay senescence in these organs. These findings provide insight into the role of renal protein reabsorption in the aging process via this tele-proteostasis network.


Assuntos
Proteínas de Drosophila , Drosophila , Envelhecimento/metabolismo , Animais , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Longevidade , Proteostase
18.
Abdom Radiol (NY) ; 46(11): 5190-5200, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34415412

RESUMO

OBJECTIVE: Oesophageal variceal bleeding (OVB) is a fatal complication of cirrhosis and/or portal hypertension. We aimed to develop a non-invasive prediction model for the risk of OVB using dual-energy computed tomography (CT). METHODS: 317 oesophageal varices (OV) patients with hepatitis B virus-related cirrhosis were retrospectively assessed from January 2018 to December 2018. All patients underwent dual-energy CT scans within 14 days before endoscopy. 222 of 317 patients (174 OVB-negative patients and 48 OVB-positive patients) were included in the training cohort and 95 patients (74 OVB-negative patients and 21 OVB-positive patients) were included in the validation cohort chronologically. A model with the selected conventional CT features and a model with the conventional CT and dual-energy CT features were developed. The prediction accuracy was evaluated using the receiver operating characteristic (ROC) curve. The accuracy and reproducibility of the models for OVB risk prediction of cirrhosis were validated by the validation cohort. The areas under the curve (AUC) of the two models were compared with Delong test. RESULTS: Diameter of oesophageal vein (OV(mm)), diameter of splenic vein (SPV(mm)), ascites (AS), iodine concentration in short gastric vein (SGV(HU)), iodine concentration in spleen (SP(HU)) were independent predictors of OVB risk (P < 0.05). Then, we developed a model with the selected conventional CT features [OV(mm), SPV(mm), AS] and a model with the conventional CT and dual-energy CT features [OV(mm), SPV(mm), AS, SGV(HU), SP(HU)]. The AUCs of the model built with the conventional CT and dual-energy CT features were higher than the model built only with the conventional CT features in the training (0.839 vs 0.809) and validation cohorts (0.798 vs 0.738). CONCLUSION: The non-invasive prediction model developed with the conventional CT and dual-energy CT features may have added value in noninvasively predicting OVB than the model built only with the conventional CT features and may have significant clinical implications on early prevention and treatment of OVB. ADVANCES IN KNOWLEDGE: Combination of dual-energy CT with conventional CT may have added value for non-invasive prediction of OVB compared to conventional CT.


Assuntos
Varizes Esofágicas e Gástricas , Hepatite B , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemorragia Gastrointestinal/etiologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
19.
Front Microbiol ; 12: 687785, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305848

RESUMO

Genetic variability has significant impacts on biological characteristics and pathogenicity of hepatitis B virus (HBV), in which the N-terminal sequence of the presurface 1 (preS1) region of HBV large surface protein (LHBs) displays genotype (GT) dependent genetic heterogeneity. However, the influence of this heterogeneity on its biological roles is largely unknown. By analyzing 6560 full-length genome sequences of GTA-GTH downloaded from HBVdb database, the preS1 N-terminal sequences were divided into four representative types, namely C-type (representative of GTA, GTB, and GTC), H-type (GTF and GTH), E-type (GTE and GTG), and D-type (GTD), respectively. We artificially substituted the preS1 N-termini of GTC and GTD plasmids or viral strains with each sequence of the four representative types. The roles of preS1 N-terminus on HBV replication, secretion and infectivity were investigated using HepG2 or HepG2-NTCP cells. In the transfection experiments, the results showed that the extracellular HBsAg levels and HBsAg secretion coefficients in D- and E-type strains were significantly higher than those in C- and H-type strains. D-type strain produced more extracellular HBV DNA than C-type strain. We further observed that D-, H-, and E-type strains increased the levels of intracellular replicative HBV DNAs, comparing with C-type strain. In the infection experiments, the levels of extracellular HBeAg, intracellular HBV total RNA and pgRNA/preC mRNA in D- and E-type strains were markedly higher than C and H-type ones. Our data suggest that the preS1 N-termini affect HBV replication, secretion and infectivity in a genotype dependent manner. The C- and H-type strains prefer to attenuate HBsAg secretion, while the strains of D- and E-type promoted infectivity. The existence and function of the intergenotypic shift of preS1 in naturally occurring recombination requires further investigation, as the data we acquired are mostly related to recombinant preS1 region between N-terminus of preS1 from genotypes A-H and the remaining preS1 portion of GTC or GTD.

20.
Eur J Neurosci ; 54(3): 4827-4837, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34132424

RESUMO

Disturbance in calcium (Ca2+ ) homeostasis has been involved in a variety of neuropathological conditions including Parkinson's disease (PD). The Ca2+ channel, transient receptor potential channel 1 (TRPC1), plays a protective role in regulating entry of Ca2+ activated by store depletion of Ca2+ in endoplasmic reticulum (ER). We have showed that thioredoxin-1 (Trx-1) plays a role in suppressing ER stress in PD. However, whether Trx-1 regulates TRPC1 expression in PD is still unknown. In the present study, we demonstrated that treatment of 1-methyl-4-phenylpyridinum ion (MPP+ ) significantly reduced the expression of TRPC1 in PC12 cells, which was restored by Trx-1 overexpression, and further decreased significantly by Trx-1 siRNA. Moreover, we found that Ca2+ entered into the cells was decreased by MPP+ in PC 12 cells, which was restored by Trx-1 overexpression, and further decreased by Trx-1 siRNA. MPP+ significantly increased calcium-dependent cysteine protease calpain1 expression in PC12 cells, which was suppressed by Trx-1 overexpression. Calpain1 expression was increased by Trx-1 siRNA or SKF96365, an inhibitor of TRPC1. Moreover, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) decreased TRPC1 expression in the substantia nigra pars compacta region (SNpc), which was restored in mice overexpressing Trx-1, and further decreased in mice of knockdown Trx-1. Inversely, the expression of calpain1 was increased by MPTP, which was suppressed in mice overexpressing Trx-1, and further increased in mice of knockdown Trx-1. In conclusion, Trx-1 regulates the Ca2+ entry through regulating TRPC1 expression after treatment of MPP+ /MPTP.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Doença de Parkinson , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Cálcio , Modelos Animais de Doenças , Homeostase , Camundongos , Camundongos Endogâmicos C57BL , Células PC12 , Ratos , Tiorredoxinas/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...