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1.
Anal Chem ; 96(18): 7073-7081, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38663374

RESUMO

A spatial-potential-color-resolved bipolar electrode electrochemiluminescence biosensor (BPE-ECL) using a CuMoOx electrocatalyst was constructed for the simultaneous detection and imaging of tetracycline (TET) and lincomycin (LIN). HOF-101 emitted peacock blue light under positive potential scanning, and CdSe quantum dots (QDs) emitted green light under negative potential scanning. CuMoOx could catalyze the electrochemical reduction of H2O2 to greatly increase the Faradic current of BPE and realize the ECL signal amplification. In channel 1, CuMoOx-Aptamer II (TET) probes were introduced into the BPE hole (left groove A) by the dual aptamer sandwich method of TET. During positive potential scanning, the polarity of BPE (left groove A) was negative, resulting in the electrochemical reduction of H2O2 catalyzed by CuMoOx, and the ECL signal of HOF-101 was enhanced for detecting TET. In channel 2, CuMoOx-Aptamer (LIN) probes were adsorbed on the MXene of the driving electrode (DVE) hole (left groove B) by hydrogen-bonding and metal-chelating interactions. LIN bound with its aptamers, causing CuMoOx to fall off. During negative potential scanning, the polarity of DVE (left groove B) was negative and the Faradic current decreased. The ECL signal of CdSe QDs was reduced for detecting LIN. Furthermore, a portable mobile phone imaging platform was built for the colorimetric (CL) detection of TET and LIN. Thus, the multiple mode-resolved detection of TET and LIN could be realized simultaneously with only one potential scan, which greatly improved detection accuracy and efficiency. This study opened a new technology of BPE-ECL sensor application and is expected to shine in microchips and point-of-care testing (POCT).


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Eletrodos , Lincomicina , Medições Luminescentes , Tetraciclina , Tetraciclina/análise , Tetraciclina/química , Técnicas Biossensoriais/métodos , Lincomicina/análise , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Catálise , Pontos Quânticos/química , Compostos de Cádmio/química , Aptâmeros de Nucleotídeos/química , Compostos de Selênio/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Antibacterianos/análise , Antibacterianos/química
2.
Eur J Clin Invest ; 54(3): e14130, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38071416

RESUMO

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is a multifaceted syndrome with a complex aetiology commonly associated with comorbidities such as diabetes mellitus, obesity, hypertension and renal disease. Various diseases induce systemic, chronic and low-grade inflammation; microvascular dysfunction; metabolic stress; tissue ischemia; and fibrosis, leading to HFpEF. An effective treatment for HFpEF is lacking, largely owing to its pathophysiological heterogeneity. Recent studies have revealed that microRNAs (miRNAs) play crucial roles in regulating the pathogenesis of HFpEF and its comorbidities. METHODS: This narrative review included original articles and reviews published over the past 20 years found through 'PubMed' and 'Web of Science'. The search terms included "HFpEF," "MicroRNAs," "comorbidities," "Microvascular Dysfunction (MVD)," "inflammation," "pathophysiology," "endothelial dysfunction," "energy metabolism abnormalities" "cardiac fibrosis" and "treatment." RESULTS: Inflammation, MVD, abnormal energy metabolism, myocardial hypertrophy and myocardial fibrosis are important pathophysiological mechanisms underlying HFpEF. As gene expression regulators, miRNAs may contribute to the pathophysiology of HFpEF and are expected to serve in the stratification of patients with HFpEF and as prognostic indicators for monitoring treatment responses. CONCLUSIONS: A customized strategy based on miRNAs has emerged as an effective treatment for HFpEF. In this review, we discuss recent research surrounding miRNAs and HFpEF and propose potential miRNA targets for the pathophysiology of HFpEF and its comorbidities. Although current research concerning miRNAs and their therapeutic potential is in its early stages, miRNA-based diagnostics and therapeutics hold great promise in the future.


Assuntos
Insuficiência Cardíaca , MicroRNAs , Humanos , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Volume Sistólico/fisiologia , Inflamação , Fibrose
3.
Appl Opt ; 63(12): 3162-3167, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856461

RESUMO

The paper proposes a spot positioning method based on a four-quadrant detector for the limited computing power and memory of spaceborne laser communication, in which the adaptive interpolation segmentation (AIS) algorithm is used to fit the theoretical position curve. The algorithm uses linear operations though the fitting process and the simulated result indicates that it has higher positioning accuracy in the center area of the quadrant detector. A spot receiving and positioning system was built for experimentation and the final location of the spot was calculated. The positioning error is analyzed to evaluate the performance of the whole system. It is shown that the positioning accuracy is highest in the stable communication area of the system. In result, the scheme achieves high accuracy with simple operations, which is more suitable for spaceborne laser communication systems to release more performance for communication.

4.
BMC Geriatr ; 24(1): 420, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734596

RESUMO

BACKGROUND: Sarcopenia and cognitive impairment have been linked in prior research, and both are linked to an increased risk of mortality in the general population. Muscle mass is a key factor in the diagnosis of sarcopenia. The relationship between low muscle mass and cognitive function in the aged population, and their combined impact on the risk of death in older adults, is currently unknown. This study aimed to explore the correlation between low muscle mass and cognitive function in the older population, and the relationship between the two and mortality in older people. METHODS: Data were from the National Health and Nutrition Examination Survey 1999-2002. A total of 2540 older adults aged 60 and older with body composition measures were included. Specifically, 17-21 years of follow-up were conducted on every participant. Low muscle mass was defined using the Foundation for the National Institute of Health and the Asian Working Group for Sarcopenia definitions: appendicular lean mass (ALM) (< 19.75 kg for males; <15.02 kg for females); or ALM divided by body mass index (BMI) (ALM: BMI, < 0.789 for males; <0.512 for females); or appendicular skeletal muscle mass index (ASMI) (< 7.0 kg/m2 for males; <5.4 kg/m2 for females). Cognitive functioning was assessed by the Digit Symbol Substitution Test (DSST). The follow-up period was calculated from the NHANES interview date to the date of death or censoring (December 31, 2019). RESULTS: We identified 2540 subjects. The mean age was 70.43 years (43.3% male). Age-related declines in DSST scores were observed. People with low muscle mass showed lower DSST scores than people with normal muscle mass across all age groups, especially in the group with low muscle mass characterized by ALM: BMI (60-69 years: p < 0.001; 70-79 years: p < 0.001; 80 + years: p = 0.009). Low muscle mass was significantly associated with lower DSST scores after adjusting for covariates (ALM: 43.56 ± 18.36 vs. 47.56 ± 17.44, p < 0.001; ALM: BMI: 39.88 ± 17.51 vs. 47.70 ± 17.51, p < 0.001; ASMI: 41.07 ± 17.89 vs. 47.42 ± 17.55, p < 0.001). At a mean long-term follow-up of 157.8 months, those with low muscle mass were associated with higher all-cause mortality (ALM: OR 1.460, 95% CI 1.456-1.463; ALM: BMI: OR 1.452, 95% CI 1.448-1.457); ASMI: OR 3.075, 95% CI 3.063-3.088). In the ALM: BMI and ASMI-defined low muscle mass groups, participants with low muscle mass and lower DSST scores were more likely to incur all-cause mortality ( ALM: BMI: OR 0.972, 95% CI 0.972-0.972; ASMI: OR 0.957, 95% CI 0.956-0.957). CONCLUSIONS: Low muscle mass and cognitive function impairment are significantly correlated in the older population. Additionally, low muscle mass and low DSST score, alone or in combination, could be risk factors for mortality in older adults.


Assuntos
Cognição , Inquéritos Nutricionais , Sarcopenia , Humanos , Masculino , Feminino , Sarcopenia/epidemiologia , Sarcopenia/mortalidade , Idoso , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Cognição/fisiologia , Idoso de 80 Anos ou mais , Músculo Esquelético/patologia , Mortalidade/tendências , Disfunção Cognitiva/epidemiologia , Composição Corporal/fisiologia , Índice de Massa Corporal , Seguimentos
5.
BMC Geriatr ; 24(1): 460, 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38797829

RESUMO

BACKGROUND: The aging global population is experiencing escalating challenges related to cognitive deficits and dementia. This study explored the interplay between pulmonary function, physical activity, and cognitive function in older U.S. adults to identify modifiable risk factors for cognitive decline. METHODS: Utilizing NHANES 2011-2012 data, we conducted a cross-sectional analysis of 729 participants aged ≥ 60 years. Cognitive function, peak expiratory flow (PEF), and physical activity were assessed. Weighted logistic regression and mediation analyses were employed to examine associations. RESULTS: The sample size was 729 (weighted mean [SD] age, 67.1 [5.3] years; 53.6% female participants). Preliminary correlation analysis indicated a positive correlation between the global cognitive score and physical activity (ß = 0.16; p < 0.001), recreational activity (ß = 0.22; p < 0.001), and PEF in percent predicted (PEF%) (ß = 0.18; p < 0.001). Compared to those with a PEF% >100%, the PEF% (80-100%) group (OR, 2.66; 95% CI, 1.34-5.29; p = 0.005) and PEF% <80% group (OR, 3.36; 95% CI, 1.67-6.76; p = 0.001) were significantly associated with higher cognitive deficits risk. Recreational activity meeting guidelines was linked to a lower risk of cognitive deficits (OR, 0.24; 95% CI, 0.10-0.57; p = 0.001). Mediation analysis demonstrated that PEF mediates the relationship between physical activity and cognitive function. CONCLUSION: This study revealed significant associations between lower PEF, diminished physical activity, and increased cognitive deficits in elderly individuals. The results supported the hypothesis that pulmonary function may mediate the connection between activity and cognitive health, emphasizing the importance of respiratory health in cognitive aging. Recognizing these associations is crucial for clinical care and public health policy aiming to mitigate cognitive decline in aging populations. While these findings are intriguing, validation through longitudinal design studies is deemed necessary.


Assuntos
Envelhecimento , Cognição , Exercício Físico , Humanos , Feminino , Estudos Transversais , Masculino , Idoso , Pico do Fluxo Expiratório/fisiologia , Exercício Físico/fisiologia , Exercício Físico/psicologia , Cognição/fisiologia , Envelhecimento/fisiologia , Envelhecimento/psicologia , Pessoa de Meia-Idade , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Inquéritos Nutricionais/métodos
6.
Int J Mol Sci ; 25(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474246

RESUMO

The DA1-like gene family plays a crucial role in regulating seed and organ size in plants. The DA1 gene family has been identified in several species but has not yet been reported in sweet potatoes. In this study, nine, eleven, and seven DA1s were identified in cultivated sweet potato (Ipomoea batatas, 2n = 6x = 90) and its two diploid wild relatives, I. trifida (2n = 2x = 30) and I. triloba (2n = 2x = 30), respectively. The DA1 genes were classified into three subgroups based on their phylogenetic relationships with Arabidopsis thaliana and Oryza sativa (rice). Their protein physiological properties, chromosomal localization, phylogenetic relationships, gene structure, promoter cis-elements, and expression patterns were systematically analyzed. The qRT-PCR results showed that the expression levels of four genes, IbDA1-1, IbDA1-3, IbDA1-6, and IbDA1-7, were higher in the sweet potato leaves than in the roots, fiber roots, and stems. In our study, we provide a comprehensive comparison and further the knowledge of DA1-like genes in sweet potatoes, and provide a theoretical basis for functional studies.


Assuntos
Ipomoea batatas , Ipomoea batatas/genética , Filogenia , Diploide , Genoma de Planta , Genes de Plantas , Regulação da Expressão Gênica de Plantas
7.
J Am Chem Soc ; 145(28): 15331-15342, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37392396

RESUMO

Variation in the molecular architecture significantly affects the electronic and supramolecular structure of biomolecular assemblies, leading to dramatically altered piezoelectric response. However, relationship between molecular building block chemistry, crystal packing and quantitative electromechanical response is still not fully understood. Herein, we systematically explored the possibility to amplify the piezoelectricity of amino acid-based assemblies by supramolecular engineering. We show that a simple change of side-chain in acetylated amino acids leads to increased polarization of the supramolecular arrangements, resulting in significant enhancement of their piezoelectric response. Moreover, compared to most of the natural amino acid assemblies, chemical modification of acetylation increased the maximum piezoelectric tensors. The predicted maximal piezoelectric strain tensor and voltage constant of acetylated tryptophan (L-AcW) assemblies reach 47 pm V-1 and 1719 mV m/N, respectively, comparable to commonly used inorganic materials such as bismuth triborate crystals. We further fabricated an L-AcW crystal-based piezoelectric power nanogenerator that produces a high and stable open-circuit voltage of over 1.4 V under mechanical pressure. For the first time, the illumination of a light-emitting diode (LED) is demonstrated by the power output of an amino acid-based piezoelectric nanogenerator. This work presents the supramolecular engineering toward the systematic modulation of piezoelectric response in amino acid-based assemblies, facilitating the development of high-performance functional biomaterials from simple, readily available, and easily tailored building blocks.


Assuntos
Aminoácidos , Triptofano , Acetilação , Materiais Biocompatíveis , Bismuto
8.
J Viral Hepat ; 30(11): 859-869, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37723945

RESUMO

The aim of this study was to determine whether the age-Male-ALBI-Platelet (aMAP) score is applicable in community settings and how to maximise its role in risk stratification. A total of thousand five hundred and three participants had an aMAP score calculated at baseline and were followed up for about 10 years to obtain information on liver cancer incidence and death. After assessing the ability of aMAP to predict liver cancer incidence and death in terms of differentiation and calibration, the optimal risk stratification threshold of the aMAP score was explored, based on absolute and relative risks. The aMAP score achieved higher area under curves (AUCs) (almost all above 0.8) within 10 years and exhibited a better calibration within 5 years. Regarding absolute risk, the risk of incidence of and death from liver cancer showed a rapid increase after an aMAP score of 55. The cumulative incidence (5-year: 8.3% vs. 1.3% and 10-year: 20.9% vs. 3.6%) and mortality (5-year: 6.7% vs. 1.1% and 10-year: 17.5% vs. 3.1%) of liver cancer in individuals with an aMAP score of ≥55 were significantly higher than in those with a score of <55 (Grey's test p < .001). In terms of relative risk, the risk of death from liver cancer surpassed that from other causes after an aMAP score of ≥55 [HR = 1.38(1.02-1.87)]. Notably, the two types of death risk had opposite trends between the subpopulation with an aMAP score of ≥55 and < 55. To conclude, this study showed the value of the aMAP score in community settings and recommends using 55 as a new risk stratification threshold to guide subsequent liver cancer screening.


Assuntos
Hepatite B , Neoplasias Hepáticas , Humanos , Masculino , Estudos de Coortes , Seguimentos , Detecção Precoce de Câncer , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia
9.
Hell J Nucl Med ; 26(1): 20-25, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37031419

RESUMO

OBJECTIVE: Fluorine-18-fluorodeoxyglucose (18F-FDG) injection activity is positively associated with radiation dose and positron emission tomography (PET) image count. Measurement error is greater with smaller counts; therefore, precise analysis is needed to avoid high doses of radiation exposure caused by high 18F-FDG injection. We aimed to identify and validate the optimal 18F-FDG injection activity and acquisition time for cardiac viability imaging with intravenous insulin preparation administration based on fixed 18F-FDG activity. MATERIALS AND METHODS: Cardiac PET images from 30 patients with coronary artery disease (CAD) were retrospectively reconstructed into different durations. An optimal product of the maximum standardized uptake value (SUV) of the myocardium, and segmental uptake (SU), and acquisition time (MSAT) was determined through a receiver operating characteristic curve. RESULTS: The optimal acquisition time (OAT) was equal to MSAT divided by mean SUV of the myocardium (MyoSUV) and was validated in another 26 patients with CAD. The optimal MSAT was 848.2s. In the validation group, the OAT was 129±76s (95% confidence interval, 99-160s), approximately one-third of the usual acquisition time. The MyoSUV and SU were equivalent between PET image duration of OAT and 600s (7.71±3.01 vs. 7.56±2.94; 67.1±15.4% vs. 67.7±15.6%). CONCLUSION: Intravenous insulin preparation administration has the potential to decrease the radiation exposure or acquisition time in cardiac viability 18F-FDG imaging to one-third, without losing the accurate measurement of MyoSUV or SU when reaching an OAT.


Assuntos
Doença da Artéria Coronariana , Exposição à Radiação , Humanos , Fluordesoxiglucose F18 , Estudos Retrospectivos , Insulina , Miocárdio , Tomografia por Emissão de Pósitrons/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Exposição à Radiação/prevenção & controle , Compostos Radiofarmacêuticos
10.
J Am Chem Soc ; 144(40): 18375-18386, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36164777

RESUMO

Supramolecular packing dictates the physical properties of bio-inspired molecular assemblies in the solid state. Yet, modulating the stacking modes of bio-inspired supramolecular assemblies remains a challenge and the structure-property relationship is still not fully understood, which hampers the rational design of molecular structures to fabricate materials with desired properties. Herein, we present a co-assembly strategy to modulate the supramolecular packing of N-terminally capped alanine-based assemblies (Ac-Ala) by changing the amino acid chirality and mixing with a nonchiral bipyridine derivative (BPA). The co-assembly induced distinct solid-state stacking modes determined by X-ray crystallography, resulting in significantly enhanced electromechanical properties of the assembly architectures. The highest rigidity was observed after the co-assembly of racemic Ac-Ala with a bipyridine coformer (BPA/Ac-DL-Ala), which exhibited a measured Young's modulus of 38.8 GPa. Notably, BPA crystallizes in a centrosymmetric space group, a condition that is broken when co-crystallized with Ac-L-Ala and Ac-D-Ala to induce a piezoelectric response. Enantiopure co-assemblies of BPA/Ac-D-Ala and BPA/Ac-L-Ala showed density functional theory-predicted piezoelectric responses that are remarkably higher than the other assemblies due to the increased polarization of their supramolecular packing. This is the first report of a centrosymmetric-crystallizing coformer which increases the single-crystal piezoelectric response of an electrically active bio-inspired molecular assembly. The design rules that emerge from this investigation of chemically complex co-assemblies can facilitate the molecular design of high-performance functional materials comprised of bio-inspired building blocks.


Assuntos
Alanina , Aminoácidos , Cristalografia por Raios X , Estrutura Molecular
11.
Int J Mol Sci ; 23(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36142313

RESUMO

A series of symmetrical truxene-centered and 3-ethylrhodanine end-capped electron acceptors with high absorption coefficient, namely Tr(Hex)6-3RD, Tr(Dec)6-3RD, and Tr(Hex)6-6RD, were prepared and constructed for non-fullerene solar cells. To satisfy solution-processability, multiple energy levels, and suitable morphology, these three acceptors were comparatively studied through alkyl chain (hexyl/decyl) and branched-arm engineering (three/six branched arms). The six-bladed propeller acceptor of Tr(Hex)6-6RD recorded the power conversion efficiency (PCE) of 1.1% blending with PTB7-Th without additional additives and post-processing. This work highly broadens the potential applications of star-shaped truxene building blocks in the fields of organic electronics.

12.
Molecules ; 27(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36500516

RESUMO

Three homologous electrochromic conjugated polymers, each containing an asymmetric building block but decorated with distinct alkyl chains, were designed and synthesized using electrochemical polymerization in this study. The corresponding monomers, namely T610FBTT810, DT6FBT, and DT48FBT, comprise the same backbone structure, i.e., an asymmetric 5-fluorobenzo[c][1,2,5]thiadiazole unit substituted by two thiophene terminals, but were decorated with different types of alkyl chain (hexyl, 2-butyloctyl, 2-hexyldecyl, or 2-octyldecyl). The effects of the side-chain structure and asymmetric repeating unit on the optical absorption, electrochemistry, morphology, and electrochromic properties were investigated comparatively. It was found that the electrochromism conjugated polymer, originating from DT6FBT with the shortest and linear alkyl chain, exhibits the best electrochromic performance with a 25% optical contrast ratio and a 0.3 s response time. The flexible electrochromic device of PDT6FBT achieved reversible colors of navy and cyan between the neutral and oxidized states, consistent with the non-device phenomenon. These results demonstrate that subtle modification of the side chain is able to change the electrochromic properties of conjugated polymers.


Assuntos
Polímeros , Tiofenos , Polímeros/química , Polimerização , Tiofenos/química , Eletroquímica/métodos
13.
Cell Tissue Res ; 384(3): 735-744, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33502605

RESUMO

Myocardial ischemia/reperfusion injury (I/RI) frequently incurs in acute myocardial infarction with high morbidity and mortality worldwide and is characterized with cardiomyocyte apoptosis and inflammatory response. Aloin is a major anthraquinone from Aloe species and fulfills pleiotropic protective functions in several disease models including hepatic injury. Nevertheless, the potential of aloin in MI/RI remains elusive. Intriguingly, aloin had modest cytotoxicity in H9c2 cardiomyocytes. Importantly, aloin dose-dependently ameliorated cell viability that was inhibited in response to simulated ischemia/reperfusion (SI/R) stimulation. Moreover, the enhanced apoptosis in cells under SI/R conditions were reduced after aloin treatment, concomitant with the decrease in pro-apoptotic Bax protein levels and increase in anti-apoptotic Bcl-2 protein expression. Of interest, aloin administration attenuated SI/R-induced oxidant stress by decreasing reactive oxygen species (ROS) production, lactate dehydrogenase (LDH), and malondialdehyde (MDA) release and increasing activity of anti-oxidant stress enzyme superoxide dismutase (SOD). Additionally, the elevated pro-inflammatory cytokine levels were counteracted after aloin treatment in cells under SI/R conditions, including TNF-α, IL-6, and IL-1ß. Mechanically, aloin further enforced the activation of the NF-E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling. Noticeably, blockage of this pathway by si-Nrf2 transfection blunted aloin-mediated cardioprotective efficacy against SI/R-evoked oxidative stress injury and inflammatory response. Thus, these findings corroborate that aloin may antagonize SI/R-induced cardiomyocyte injury by attenuating excessive oxidative stress and inflammation, thereby endorsing its potential as a promising therapeutic agent against myocardial infarction.


Assuntos
Emodina/análogos & derivados , Inflamação/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Linhagem Celular , Emodina/farmacologia , Heme Oxigenase-1/metabolismo , Miócitos Cardíacos , Fator 2 Relacionado a NF-E2/metabolismo , Ratos
14.
Methods ; 173: 32-43, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31226302

RESUMO

Influx evidences show that red long non-coding RNAs (lncRNAs) play important roles in various critical biological processes, and they afffect the development and progression of various human diseases. Therefore, it is necessary to precisely identify the lncRNA-disease associations. The identification precision can be improved by developing data integrative models. However, current models mainly need to project heterogeneous data onto the homologous networks, and then merge these networks into a composite one for integrative prediction. We recognize that this projection overrides the individual structure of the heterogeneous data, and the combination is impacted by noisy networks. As a result, the performance is compromised. Given that, we introduce a weighted matrix factorization model on multi-relational data to predict LncRNA-disease associations (WMFLDA). WMFLDA firstly uses a heterogeneous network to capture the inter(intra)-associations between different types of nodes (including genes, lncRNAs, and Disease Ontology terms). Then, it presets weights to these inter-association and intra-association matrices of the network, and cooperatively decomposes these matrices into low-rank ones to explore the underlying relationships between nodes. Next, it jointly optimizes the low-rank matrices and the weights. After that, WMFLDA approximates the lncRNA-disease association matrix using the optimized matrices and weights, and thus to achieve the prediction. WMFLDA obtains a much better performance than related data integrative solutions across different experiment settings and evaluation metrics. It can not only respect the intrinsic structures of individual data sources, but can also fuse them with selection.


Assuntos
Biologia Computacional/métodos , Predisposição Genética para Doença , RNA Longo não Codificante/genética , Algoritmos , Progressão da Doença , Humanos
15.
BMC Womens Health ; 21(1): 7, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407384

RESUMO

BACKGROUND: The Yunnan province is located near the "Golden Triangle" border region between China, Myanmar and Thailand, which has the highest HIV/AIDS prevalence in China. Female sex workers (FSWs) in the Yunnan province are highly vulnerable to HIV infection. The objective of this study was to examine the experiences of FSWs in the Yunnan to better understand the risk of infection and the potential for transmission of HIV. METHODS: Semi-structured interviews were conducted between May 2018 and June 2018 with 20 FSWs recruited in Hekou County, Yunnan Province, China. Thematic analysis was conducted to identify themes that highlighted increased exposure of FSWs to the risk of HIV infection and transmission. RESULTS: The findings showed that FSWs' primary source for HIV information was gynecologists, with few visiting the local HIV charity Red Ribbon. FSWs reported infrequent visits for check-ups with some seeing a gynecologist once a year. FSWs felt that the onus was on them to prevent STI/HIV infection by using a condom during sex, regardless of their ability to negotiate use. FSWs were also reluctant to see a gynecologists for treatment. Instead, they resorted to douching as a way of preventing HIV/STIs and treating vaginal health problems, such as leucorrhea. Most FSWs worked without the influence of alcohol and drugs. A small number of FSWs reported heroin addiction and injecting drug use. CONCLUSION: The findings suggest a need for innovative HIV prevention strategies among FSWs and their clients in the Chinese border region. Governmental agencies should continue to implement practical strategies in terms of HIV prevention education and condom use through tailored interventions that are localized. Such strategies should include localized tailored interventions that dispel myths about douching as a method of HIV/STI prevention and incorporate a mobile outreach approach, similar to the 'roadside restaurant' outreach that has been successful in rural China.


Assuntos
Infecções por HIV , Profissionais do Sexo , Infecções Sexualmente Transmissíveis , China/epidemiologia , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Mianmar/epidemiologia , Fatores de Risco , Infecções Sexualmente Transmissíveis/epidemiologia , Tailândia , Vietnã
16.
Int J Mol Sci ; 22(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34299339

RESUMO

Silver nanowire (AgNWs) inks for inkjet printing were prepared and the effects of the solvent system, wetting agent, AgNWs suspension on the viscosity, surface tension, contact angle between ink droplet and poly(ethylene) terephthalate (PET) surface, and pH value of AgNWs ink were discussed. Further, AgNWs flexible transparent conductive films were fabricated by using inkjet printing process on the PET substrate, and the effects of the number printing layer, heat treatment temperature, drop frequency, and number of nozzle on the microstructures and photoelectric properties of AgNWs films were investigated in detail. The experimental results demonstrated that the 14-layer AgNWs printed film heated at 60 °C and 70 °C had an average sheet resistance of 13 Ω∙sq-1 and 23 Ω∙sq-1 and average transparency of 81.9% and 83.1%, respectively, and displayed good photoelectric performance when the inkjet printing parameters were set to the voltage of 20 V, number of nozzles of 16, drop frequency of 7000 Hz, droplet spacing of 15 µm, PET substrate temperatures of 40 °C and nozzles of 35 °C during printing, and heat treatment at 60 °C for 20 min. The accumulation and overflow of AgNWs at the edges of the linear pattern were observed, which resulted in a decrease in printing accuracy. We successfully printed the heart-shaped pattern and then demonstrated that it could work well. This showed that the well-defined pattern with good photoelectric properties can be obtained by using an inkjet printing process with silver nanowires ink as inkjet material.


Assuntos
Nanopartículas Metálicas/química , Nanofios/química , Impressão/métodos , Condutividade Elétrica , Tinta , Prata/química , Temperatura
17.
Opt Express ; 28(26): 38960-38972, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33379454

RESUMO

Early radar warning is a significant step to lessen the fine scanning range of a receiver. The small size two-dimension (2-D) angle-of-arrival (AOA) estimation part with moderate accuracy and sensitivity is important for an early radar warning receiver. In our method, we specially design an L-shaped antenna array (L-sAA) and connect it with dual-polarization binary phase shift keying modulator (DP-BPSKM). The dual-sideband (DSB) modulation is performed to transfer most of the optical power to electrical, so as to increase the sensitivity. It is also possible to map the AOA information of the incoming beam to photo-detected electrical power without a high extinction ratio modulator or optical filter. During the estimation, the 2-D AOA is firstly measured, whose measurement range is 18.22°âˆ¼90° and the measurement error is lower than 1°. Then, based on the 2-D AOA estimation results, the third one is mathematically calculated to construct 3-D location of the target. Noteworthy, the amplitude comparison function (ACF) is adopted in this method to make the system response irrelative to the received signal power, which endows the system with signal power fluctuation immunity. Experimental results show that this method is capable of measuring a single-tone signal and a bandwidth signal. This structure is very concise and meets the potential of on-chip integration.

18.
BMC Bioinformatics ; 20(Suppl 15): 547, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31874623

RESUMO

BACKGROUND: Traditional drug research and development is high cost, time-consuming and risky. Computationally identifying new indications for existing drugs, referred as drug repositioning, greatly reduces the cost and attracts ever-increasing research interests. Many network-based methods have been proposed for drug repositioning and most of them apply random walk on a heterogeneous network consisted with disease and drug nodes. However, these methods generally adopt the same walk-length for all nodes, and ignore the different contributions of different nodes. RESULTS: In this study, we propose a drug repositioning approach based on individual bi-random walks (DR-IBRW) on the heterogeneous network. DR-IBRW firstly quantifies the individual work-length of random walks for each node based on the network topology and knowledge that similar drugs tend to be associated with similar diseases. To account for the inner structural difference of the heterogeneous network, it performs bi-random walks with the quantified walk-lengths, and thus to identify new indications for approved drugs. Empirical study on public datasets shows that DR-IBRW achieves a much better drug repositioning performance than other related competitive methods. CONCLUSIONS: Using individual random walk-lengths for different nodes of heterogeneous network indeed boosts the repositioning performance. DR-IBRW can be easily generalized to prioritize links between nodes of a network.


Assuntos
Reposicionamento de Medicamentos , Biologia Computacional , Aprovação de Drogas , Reposicionamento de Medicamentos/métodos
19.
Circ Res ; 120(5): e7-e23, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28137917

RESUMO

RATIONALE: Endothelial progenitor cells (EPCs) respond to stromal cell-derived factor 1 (SDF-1) through chemokine receptors CXCR7 and CXCR4. Whether SDF-1 receptors involves in diabetes mellitus-induced EPCs dysfunction remains unknown. OBJECTIVE: To determine the role of SDF-1 receptors in diabetic EPCs dysfunction. METHODS AND RESULTS: CXCR7 expression, but not CXCR4 was reduced in EPCs from db/db mice, which coincided with impaired tube formation. Knockdown of CXCR7 impaired tube formation of EPCs from normal mice, whereas upregulation of CXCR7 rescued angiogenic function of EPCs from db/db mice. In normal EPCs treated with oxidized low-density lipoprotein or high glucose also reduced CXCR7 expression, impaired tube formation, and increased oxidative stress and apoptosis. The damaging effects of oxidized low-density lipoprotein or high glucose were markedly reduced by SDF-1 pretreatment in EPCs transduced with CXCR7 lentivirus but not in EPCs transduced with control lentivirus. Most importantly, EPCs transduced with CXCR7 lentivirus were superior to EPCs transduced with control lentivirus for therapy of ischemic limbs in db/db mice. Mechanistic studies demonstrated that oxidized low-density lipoprotein or high glucose inhibited protein kinase B and glycogen synthase kinase-3ß phosphorylation, nuclear export of Fyn and nuclear localization of nuclear factor (erythroid-derived 2)-like 2 (Nrf2), blunting Nrf2 downstream target genes heme oxygenase-1, NAD(P)H dehydrogenase (quinone 1) and catalase, and inducing an increase in EPC oxidative stress. This destructive cascade was blocked by SDF-1 treatment in EPCs transduced with CXCR7 lentivirus. Furthermore, inhibition of phosphatidylinositol 3-kinase/protein kinase B prevented SDF-1/CXCR7-mediated Nrf2 activation and blocked angiogenic repair. Moreover, Nrf2 knockdown almost completely abolished the protective effects of SDF-1/CXCR7 on EPC function in vitro and in vivo. CONCLUSIONS: Elevated expression of CXCR7 enhances EPC resistance to diabetes mellitus-induced oxidative damage and improves therapeutic efficacy of EPCs in treating diabetic limb ischemia. The benefits of CXCR7 are mediated predominantly by a protein kinase B/glycogen synthase kinase-3ß/Fyn pathway via increased activity of Nrf2.


Assuntos
Diabetes Mellitus/metabolismo , Células Progenitoras Endoteliais/fisiologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Isquemia/metabolismo , Proteínas Proto-Oncogênicas c-fyn/metabolismo , Receptores CXCR/biossíntese , Animais , Células Cultivadas , Diabetes Mellitus/patologia , Técnicas de Silenciamento de Genes , Células HEK293 , Membro Posterior/irrigação sanguínea , Membro Posterior/metabolismo , Membro Posterior/patologia , Humanos , Isquemia/patologia , Masculino , Camundongos , Camundongos Transgênicos , Fator 2 Relacionado a NF-E2/metabolismo , Neovascularização Fisiológica/fisiologia , Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo
20.
J Nanosci Nanotechnol ; 19(1): 235-239, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30327029

RESUMO

In this work, PbS quantum dots were for the first time directly deposited on graphene nanowalls substrate by electrochemical atomic layer epitaxy (ECALE) deposition method. The morphology, composition and 3D structure of PbS/graphene were characterized by field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD) and Raman spectrum, respectively. The sensitized three-dimensional graphene electrode with PbS quantum dots had great improvement in the performance of photo-electrochemical (PEC), with photocurrent almost four times that of pure graphene film, which presents its great application potential in the fields of photodetector or solar cell.

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