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1.
BMC Geriatr ; 24(1): 529, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890578

RESUMEN

BACKGROUND: Physical disability is an important cause of affecting the quality of life in the elderly. The association between standing height and physical disability is less studied. PURPOSE: The purpose of this study is to investigate the possible link between standing height and physical disability among U.S. adults aged 60 years and older. METHODS: The cross-sectional data were obtained from the US National Health and Nutrition Examination Survey (NHANES) 2015-2018. Physical disability was assessed by six questions: "Have serious difficulty hearing (SDH)?", "Have serious difficulty seeing (SDS)?", "Have serious difficulty concentrating (SDC)?", "Have serious difficulty walking (SDW)?", "Have difficulty dressing or bathing (DDB)?" and "Have difficulty doing errands alone (DDEA)?". Responses to these questions were "yes" or "no". Answer yes to one of the above six questions was identified as physical disability. Standing height (cm) was measured with an altimeter. Multivariate logistic regression was performed to examine the possible link between standing height and physical disability after adjustment for all covariates. RESULTS: A total of 2624 participants aged ≥ 60 years were included in our study, including 1279 (48.7%) females and 1345 (51.3%) males. The mean age of participants was 69.41 ± 6.82 years. After adjusting for all potential confounders, the inverse relationship between standing height and all physical disability (APD) was statistically significant (OR = 0.976, 95%CI:0.957-0.995). In addition, among six types of physical disability (SDH, SDS, SDC, SDW, DDB, DDEA), standing height was also a protective factor for SDW (OR = 0.961, 95%CI:0.939-0.983) and DDEA (OR = 0.944, 95%CI:0.915-0.975) in the full-adjusted model. CONCLUSION: The cross-sectional population based study demonstrates that standing height is a protective factor for physical disability among U.S. adults aged 60 years and older.


Asunto(s)
Estatura , Personas con Discapacidad , Encuestas Nutricionales , Humanos , Femenino , Masculino , Anciano , Estudios Transversales , Persona de Mediana Edad , Encuestas Nutricionales/métodos , Estados Unidos/epidemiología , Estatura/fisiología , Anciano de 80 o más Años , Posición de Pie , Evaluación de la Discapacidad
2.
Plants (Basel) ; 13(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38732442

RESUMEN

Soil alkalization is an important environmental factor limiting crop production. Despite the importance of root secretion in the response of plants to alkali stress, the regulatory mechanism is unclear. In this study, we applied a widely targeted metabolomics approach using a local MS/MS data library constructed with authentic standards to identify and quantify root exudates of wheat under salt and alkali stresses. The regulatory mechanism of root secretion in alkali-stressed wheat plants was analyzed by determining transcriptional and metabolic responses. Our primary focus was alkali stress-induced secreted metabolites (AISMs) that showed a higher secretion rate in alkali-stressed plants than in control and salt-stressed plants. This secretion was mainly induced by high-pH stress. We discovered 55 AISMs containing -COOH groups, including 23 fatty acids, 4 amino acids, 1 amino acid derivative, 7 dipeptides, 5 organic acids, 9 phenolic acids, and 6 others. In the roots, we also discovered 29 metabolites with higher levels under alkali stress than under control and salt stress conditions, including 2 fatty acids, 3 amino acid derivatives, 1 dipeptide, 2 organic acids, and 11 phenolic acids. These alkali stress-induced accumulated carboxylic acids may support continuous root secretion during the response of wheat plants to alkali stress. In the roots, RNAseq analysis indicated that 5 6-phosphofructokinase (glycolysis rate-limiting enzyme) genes, 16 key fatty acid synthesis genes, and 122 phenolic acid synthesis genes have higher expression levels under alkali stress than under control and salt stress conditions. We propose that the secretion of multiple types of metabolites with a -COOH group is an important pH regulation strategy for alkali-stressed wheat plants. Enhanced glycolysis, fatty acid synthesis, and phenolic acid synthesis will provide more energy and substrates for root secretion during the response of wheat to alkali stress.

3.
Sci Rep ; 14(1): 9727, 2024 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-38678062

RESUMEN

Vitamin C is an important micronutrient for human. Association between vitamin C and trouble sleeping was less studied. Therefore, the purpose of this study was to investigate the possible link between vitamin C in serum and trouble sleeping. The cross-sectional data was derived from the National Health and Nutrition Examination Survey (NHANES, 2017-2018). Trouble sleeping was measured by asking participants: "Have you ever told doctor had trouble sleeping". Responses to this question was "yes" or "no". vitamin C in serum was obtained by measuring the serum samples. We used multivariable binary logistic regressions to examine the possible link between vitamin C in serum and trouble sleeping, and then a subgroup analysis was performed. Moreover, the non-linear relationship between vitamin C in serum and trouble sleeping was further detected using a restricted cubic spline (RCS) model. A total of 3227 participants were included in the study. After adjusting all potential confounders, the results of multivariable logistic regression showed the significant negative association between vitamin C in serum and trouble sleeping(OR = 0.816; 95% CI:0.669 ~ 0.995). The significant inverse association was also found in female(OR = 0.713; 95% CI:0.546 ~ 0.931), age ≤ 65 years(OR = 0.773; 95% CI:0.600 ~ 0.996), and in participants with high cholesterol level(OR = 0.738; 95% CI:0.548 ~ 0.994). In addition, the RCS model demonstrated the significant non-linear relationship between vitamin C in serum and trouble sleeping (P value of nonlinear = 0.010). Our study demonstrates the significant negative association between vitamin C in serum and trouble sleeping.


Asunto(s)
Ácido Ascórbico , Encuestas Nutricionales , Humanos , Ácido Ascórbico/sangre , Femenino , Masculino , Persona de Mediana Edad , Adulto , Estudios Transversales , Anciano , Trastornos del Sueño-Vigilia/sangre , Trastornos del Sueño-Vigilia/epidemiología , Modelos Logísticos
4.
Front Public Health ; 12: 1322244, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38532980

RESUMEN

Objective: The purpose of this investigation was to evaluate the potential link between physical activity (PA) and the heightened susceptibility to diabetes mellitus (DM), by examining whether remnant cholesterol (RC) might act as a mediator in this correlation. Methods: The research utilized data from the National Health and Nutrition Examination Survey, spanning from 2005 to 2018. Various statistical analyses were conducted for continuous and categorical variables, including the t-test, ANOVA, and χ2 test. Logistic regression was employed to analyze the association between PA and DM across three distinct models. Mediation analysis was also conducted to assess the potential mediation effects of RC. Results: The study encompassed a total of 9,149 participants, and it was observed that individuals with DM exhibited lower levels of PA. Furthermore, PA levels were found to be associated with all participant characteristics except poverty income ratio, fasting blood glucose, and HOMA-IR (p < 0.05). After adjusting for covariates (Model 3), individuals with high PA levels demonstrated a decreased likelihood of developing DM compared to those in the low PA group (OR: 0.73, 95%CI: 0.54-0.99). A significant dose-response relationship was identified (p < 0.05). No interaction between PA and RC in relation to DM risk was detected, and RC was found to serve as a mediator in the connection between PA and DM. After considering covariates, the mediating effect of RC between PA and DM weakens. Discussion: Our findings suggest that higher levels of PA are linked to a reduced risk of DM in U.S. adults, with RC likely playing a mediating role.


Asunto(s)
Diabetes Mellitus , Adulto , Humanos , Encuestas Nutricionales , Diabetes Mellitus/diagnóstico , Colesterol , Ejercicio Físico
5.
Child Adolesc Psychiatry Ment Health ; 17(1): 113, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37794411

RESUMEN

BACKGROUND: The psychological impact of the COVID-19 pandemic has been understudied among vulnerable populations. This study aimed to examine the immediate and longer-term changes in the mental health of children with parent-child separation experiences during the COVID-19 pandemic, and identify potential buffering opportunities for mental health. METHODS: This longitudinal cohort study used data from 723 rural Chinese children who provided data before (Oct. 2019) the COVID-19 pandemic and during the following 2 years. Changes in the probability of depressive symptoms, anxiety symptoms, non-suicide self-injurious (NSSI), suicidal ideation, suicide plan, and suicide attempt were tested across four waves using generalized estimating models (GEE). RESULTS: Compared with children who never experienced parent-child separation, children persistently separated from parents since birth experienced greater deterioration in all mental health in the 2-year follow-up (average change: depressive symptoms: ß = 0.59, 95% CI [0.26, 0.93]; anxiety symptoms: ß = 0.45, 95% CI [0.10, 0.81]; NSSI: ß = 0.66, 95% CI [0.31, 1.01]; suicide ideation: ß = 0.67, 95% CI [0.38, 0.96]; suicide plan: ß = 0.77, 95% CI [0.38, 1.15]; suicide attempt: ß = 1.12, 95% CI [0.63, 1.62]). However, children with childhood separation from their parents but reunited with them during the transition to adolescence showed similar even lower changes to counterparts who never experienced parent-child separation (all ps > 0.05). CONCLUSION: These results indicating improvements in supportiveness of the caregiving environment during the transition to adolescence may provide the opportunity to buffer the adverse impact of COVID-19 on mental health. Translating such knowledge to inform intervention and prevention strategies for youths exposed to adversity is a critical goal for the field.

6.
Analyst ; 148(19): 4820-4828, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37606537

RESUMEN

Cervical cancer is a significant global health issue primarily caused by high-risk types of human papillomavirus (HPV). Recent studies have reported an association between Trichomonas vaginalis (T. vaginalis) infections and HPV infections, highlighting the importance of simultaneously detecting these pathogens for effective cervical cancer risk management. However, current methods for detecting both T. vaginalis and HPV are limited. In this study, we present a novel approach using a microfluidic-chip-based system with loop-mediated isothermal amplification (LAMP) for the rapid and parallel detection of T. vaginalis, HPV16, HPV18, and HPV52 in a reagent-efficient and user-friendly manner. Compared to conventional LAMP assays in tubes, our system exhibits enhanced sensitivity with values of 2.43 × 101, 3.00 × 102, 3.57 × 101, and 3.60 × 102 copies per reaction for T. vaginalis, HPV16, HPV18, and HPV52, respectively. Additionally, we validated the performance of our chip by testing 47 clinical samples, yielding results consistent with the diagnostic methods used by the hospital. Therefore, our system not only offers a promising solution for concurrent diagnosis of T. vaginalis and HPV infections, particularly in resource-limited areas, due to its cost-effectiveness, ease of use, and rapid and accurate detection performance, but can also contribute to future research on the co-infection of these two pathogens. Moreover, the system possesses the capability to simultaneously detect up to 22 different types of pathogens, making it applicable across a wide range of domains such as diagnostics, food safety, and water monitoring.


Asunto(s)
Infecciones por Papillomavirus , Trichomonas vaginalis , Neoplasias del Cuello Uterino , Femenino , Humanos , Trichomonas vaginalis/genética , Virus del Papiloma Humano , Infecciones por Papillomavirus/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Microfluídica , Sensibilidad y Especificidad , Técnicas de Amplificación de Ácido Nucleico/métodos , Papillomavirus Humano 16 , Papillomavirus Humano 18/genética
7.
Physiol Behav ; 270: 114305, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37507079

RESUMEN

A trend toward earlier pubertal maturation in both sexes has been shown in many countries. Early puberty affects an increasing proportion of children for reasons that remain obscure. Novel candidate biomarkers are strongly needed. We sought to apply untargeted metabolomic profiling to identify triggering mechanisms and candidate biomarkers in children with early puberty. Participants aged 7 - 12 years old were recruited directly from two elementary schools of Bengbu, Anhui Province, China, from Feb 2021 to May 2021. Early puberty was determined by breast and testicular development at baseline (May 2021) and 6-month later. Ultra-high-performance liquid chromatography-based untargeted metabolomic profiling was performed on urine samples of children with early puberty and control subjects. Metabolomic profiling for early puberty in a sex dependent manner. For boys, we identified several perturbed pathways, including histidine metabolism, glycine, serine and threonine metabolism, and selenoamino acid metabolism, associated with early puberty. In contrast, there were differences in pyruvate metabolism, one carbon pool by folate, and D-glutamine and D-glutamate metabolism pathways in girls with early puberty compared with controls. In addition, 4-hydroxyhippuric acid and 5-methoxytryptophol were shown as potential independent diagnostic biomarker for early puberty in boys, 3-hydroxybenzoic acid and glutaminylproline were shown as early biomarker for early puberty in girls, achieving area under the ROC curve of 0.71 and 0.72 in discriminating early puberty boys, and 0.70 and 0.74 in discriminating early puberty girls from controls. Through metabolomic analysis, we have identified metabolic perturbations and potential biomarkers of early puberty.


Asunto(s)
Metabolómica , Pubertad , Masculino , Femenino , Humanos , Niño , Biomarcadores/orina , China , Cromatografía Líquida de Alta Presión
8.
Small ; 19(42): e2302717, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37340893

RESUMEN

Step-scheme (S-scheme) heterojunctions have exhibited great potential in photocatalysis due to their extraordinary light harvesting and high redox capacities. However, inadequate S-scheme recombination of useless carriers in weak redox abilities increases the probability of their recombination with useful ones in strong redox capabilities. Herein, a versatile protocol is demonstrated to overcome this impediment based on the insertion of nano-piezoelectrics into the heterointerfaces of S-scheme heterojunctions. Under light excitation, the piezoelectric inserter promotes interfacial charge transfer and produces additional photocarriers to recombine with useless electrons and holes, ensuring a more thorough separation of powerful ones for CO2 reduction and H2 O oxidation. When introducing extra ultrasonic vibration, a piezoelectric polarization field is established, which allows efficient separation of charges generated by the embedded piezoelectrics and expedites their recombination with weak carriers, further increasing the number of strong ones participating in the redox reactions. Encouraged by the greatly improved charge utilization, significantly enhanced photocatalytic and piezophotocatalytic activities in CH4 , CO, and O2 production are achieved by the designed stacked catalyst. This work highlights the importance in strengthening the necessary charge recombination in S-scheme heterojunctions and presents an efficient and novel strategy to synergize photocatalysis and piezocatalysis for renewable fuels and value-added chemicals production.

9.
J Adolesc Health ; 73(1): 53-60, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37037691

RESUMEN

PURPOSE: The aim of the study was to explore the long-term impacts of parent-child separation on a broad set of health and well-being indicators during adolescence and emerging adulthood. METHODS: Participants were from the China Family Panel Studies, a national representative prospective cohort, and 2710 adolescents aged 7-15 years recruited from 25 provinces after an 8-year follow-up were eventually included in this study. We examined the association of prolonged parent-child separation with educational, social, emotional, and health-related outcomes by comparing participants with experience of prolonged parent-child separation and their counterparts staying with parents. RESULTS: Participants who experienced prolonged parent-child separation in childhood were more likely to have lower educational attainment (odds ratio [OR]: 1.69, 95% confidence interval [CI]: 1.03, 2.76; p = .04), depression (OR: 2.63, 95% CI: 1.28, 5.41; p = .008), marriage or cohabitation (OR: 2.79, 95% CI: 1.40, 5.57; p = .004), and ever-smoke (OR: 3.39, 95% CI: 1.95, 5.91; p < .001). Prolonged parent-child separation was also associated with a 0.64-year loss in educational attainment, 2.99- and 2.39-unit decreases in math and word test score, as well as 2.08 kg/m2 decreases in body mass index. DISCUSSION: This nationally representative study indicates that prevention efforts that reduce exposure to parent-child separation in childhood could substantially reduce the lifetime prevalence of educational, emotional, behavioral, and cognitive problems in the general population.


Asunto(s)
Emociones , Padres , Humanos , Adolescente , Adulto , Estudios Prospectivos , Escolaridad , Relaciones Padres-Hijo
10.
Chaos ; 33(4)2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37097951

RESUMEN

Reconstructing network connections from measurable data facilitates our understanding of the mechanism of interactions between nodes. However, the unmeasurable nodes in real networks, also known as hidden nodes, introduce new challenges for reconstruction. There have been some hidden node detection methods, but most of them are limited by system models, network structures, and other conditions. In this paper, we propose a general theoretical method for detecting hidden nodes based on the random variable resetting method. We construct a new time series containing hidden node information based on the reconstruction results of random variable resetting, theoretically analyze the autocovariance of the time series, and finally provide a quantitative criterion for detecting hidden nodes. We numerically simulate our method in discrete and continuous systems and analyze the influence of main factors. The simulation results validate our theoretical derivation and illustrate the robustness of the detection method under different conditions.

11.
Artículo en Inglés | MEDLINE | ID: mdl-36897222

RESUMEN

Utilizing solar and mechanical vibration energy for catalytic CO2 reduction and H2O oxidation is emerging as a promising way to simultaneously generate renewable energy and mitigate climate change, making it possible to integrate two energy resources into a reaction system for artificial piezophotosynthesis. However, the practical applications are hindered by undesirable charge recombination and sluggish surface reaction in the photocatalytic and piezocatalytic processes. This study proposes a dual cocatalyst strategy to overcome these obstacles and improve the piezophotocatalytic performance of ferroelectrics in overall redox reactions. With the photodeposition of AuCu reduction and MnOx oxidation cocatalysts on oppositely poled facets of PbTiO3 nanoplates, band bending occurs along with the formation of built-in electric fields on the semiconductor-cocatalyst interfaces, which, together with an intrinsic ferroelectric field, piezoelectric polarization field, and band tilting in the bulk of PbTiO3, provide strong driving forces for the directional drift of piezo- and photogenerated electrons and holes toward AuCu and MnOx, respectively. Besides, AuCu and MnOx enrich the active sites for surface reactions, significantly reducing the rate-determining barrier for CO2-to-CO and H2O-to-O2 transformation, respectively. Benefiting from these features, AuCu/PbTiO3/MnOx delivers remarkably improved charge separation efficiencies and significantly enhanced piezophotocatalytic activities in CO and O2 generation. This strategy opens a door for the better coupling of photocatalysis and piezocatalysis to promote the conversion of CO2 with H2O.

12.
Small ; 19(2): e2204774, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36394158

RESUMEN

Construction of core-shell semiconductor heterojunctions and plasmonic metal/semiconductor heterostructures represents two promising routes to improved light harvesting and promoted charge separation, but their photocatalytic activities are respectively limited by sluggish consumption of charge carriers confined in the cores, and contradictory migration directions of plasmon-induced hot electrons and semiconductor-generated electrons. Herein, a semiconductor/metal/semiconductor stacked core-shell design is demonstrated to overcome these limitations and significantly boost the photoactivity in CO2  reduction. In this smart design, sandwiched Au serves as a "stone", which "kills two birds" by inducing localized surface plasmon resonance for hot electron generation and mediating unidirectional transmission of conduction band electrons and hot electrons from TiO2  core to MoS2  shell. Meanwhile, upward band bending of TiO2  drives core-to-shell migration of holes through TiO2 -MoS2  interface. The co-existence of TiO2  â†’ Au â†’ MoS2  electron flow and TiO2  â†’ MoS2  hole flow contributes to spatial charge separation on different locations of MoS2  outer layer for overall redox reactions. Additionally, reduction potential of photoelectrons participating in the CO2  reduction is elaborately adjusted by tuning the thickness of MoS2  shell, and thus the product selectivity is delicately regulated. This work provides fresh hints for rationally controlling the charge transfer pathways toward high-efficiency CO2  photoreduction.

13.
J Youth Adolesc ; 52(1): 165-176, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36149547

RESUMEN

Early life adversity is a major risk factor for the onset of psychopathology, and cellular aging may be a mechanism underlying these associations. It is unknown whether and how the pattern (timing and duration) of parent-child separation is associated with accelerated cellular aging, particularly with respect to functional aging and replicative senescence, indexed by mitochondrial DNA copy number (mtDNAcn) elevation and telomere length (TL) attrition. This cohort study included 252 rural adolescents (mean age 11.62 years, SD: 1.56). Nearly one in five participants were persistently separated from both parents since birth. Compared with participants who never separated from their parents, adolescents with prolonged parent-child separation had higher acceleration both in functional aging and replicative senescence of cells. However, that was not the case in adolescents who experienced parent-child separation in early childhood but regained stable parental care during adolescence. These findings indicate that pubertal development reopens a window of opportunity for buffering the adverse biological effect based on significant improvements in the supportiveness of the caregiving environment relative to that in childhood. Translating such knowledge to inform intervention and prevention strategies for youths exposed to adversity is a critical goal for the field.


Asunto(s)
Senescencia Celular , Acortamiento del Telómero , Humanos , Adolescente , Preescolar , Niño , Estudios de Cohortes , Senescencia Celular/genética , Biomarcadores , Relaciones Padres-Hijo
14.
Plant Commun ; 3(5): 100350, 2022 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-35733334

RESUMEN

Crop wild relatives are an important reservoir of natural biodiversity. However, incorporating wild genetic diversity into breeding programs is often hampered by reproductive barriers and a lack of accurate genomic information. We assembled a high-quality, accurately centromere-anchored genome of Gossypium anomalum, a stress-tolerant wild cotton species. We provided a strategy to discover and transfer agronomically valuable genes from wild diploid species to tetraploid cotton cultivars. With a (Gossypium hirsutum × G. anomalum)2 hexaploid as a bridge parent, we developed a set of 74 diploid chromosome segment substitution lines (CSSLs) of the wild cotton species G. anomalum in the G. hirsutum background. This set of CSSLs included 70 homozygous substitutions and four heterozygous substitutions, and it collectively contained about 72.22% of the G. anomalum genome. Twenty-four quantitative trait loci associated with plant height, yield, and fiber qualities were detected on 15 substitution segments. Integrating the reference genome with agronomic trait evaluation of the CSSLs enabled location and cloning of two G. anomalum genes that encode peroxiredoxin and putative callose synthase 8, respectively, conferring drought tolerance and improving fiber strength. We have demonstrated the power of a high-quality wild-species reference genome for identifying agronomically valuable alleles to facilitate interspecific introgression breeding in crops.


Asunto(s)
Fibra de Algodón , Gossypium , Cromosomas de las Plantas/genética , Cruzamientos Genéticos , Gossypium/genética , Fitomejoramiento
15.
Front Med (Lausanne) ; 9: 826900, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572983

RESUMEN

Background: The outbreak of coronavirus disease (COVID-19) poses a great threat to global public health. At present, the number of newly confirmed COVID-19 cases and deaths is increasing worldwide. The strategy of comprehensive and scientific detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through quantitative real-time polymerase chain reaction (qRT-PCR) for special populations and environments provides great support for the prevention and control of this pandemic in China. Our study focused on determining the factors associated with the length of time from symptom onset to the first positive nucleic acid test of throat swabs in COVID-19 patients, evaluating the effect of early positive nucleic acid detection on the disease severity and its significance in prognosis, and predicting the factors associated with the time from positive SARS-CoV-2 RNA test to negative conversion (negative conversion of SARS-CoV-2 virus) in COVID-19 patients. Methods: This study included 116 hospitalized patients with COVID-19 from January 30, 2020 to March 4, 2020 in Wuhan, China. Throat swab samples were collected for qRT-PCR testing of SARS-CoV-2 RNA, and all patients included in this study were positive for this test. Results: The multivariate Cox proportional hazards model showed that disease severity (HR = 0.572; 95% CI 0.348-0.942; p = 0.028) was a protective factor for the time from symptom onset to positive nucleic acid detection. Meanwhile, the time from symptom onset to positive nucleic acid detection (HR = 1.010; 95% CI 1.005-1.020; p = 0.0282) was an independent risk factor for the delay in negative conversion time of SARS-CoV-2 virus. However, the severity of the disease (HR=1.120; 95% CI 0.771-1.640; p = 0.544) had no correlation with the negative conversion time of SARS-CoV-2 virus. Conclusions: Patients with more severe disease had a shorter time from symptom onset to a positive nucleic acid test. Prolonged time from symptom onset to positive nucleic acid test was an independent risk factor for the delay in negative conversion time of SARS-CoV-2 virus, and the severity of the disease had no correlation with negative conversion time of SARS-CoV-2 virus.

16.
Chem Commun (Camb) ; 58(32): 5009-5012, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35362504

RESUMEN

Herein, a signal-on liquid crystal microarray (LCM) sensor is designed for the first time with a micro-spectral optical sensing signal. Depending on the change of the orientation of the LC molecules in the LCM films and the intensity of the spectral peaks of the PhCs, the signal-on LCM biosensor achieves the detection of AFB1 and the Partial Response Mechanism (PSM) of the LCM films is discovered.


Asunto(s)
Técnicas Biosensibles , Cristales Líquidos , Aflatoxina B1/análisis , Bioensayo , Límite de Detección , Análisis por Micromatrices
17.
Anal Chem ; 94(14): 5530-5537, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35357128

RESUMEN

The stimuli-responsive DNA hydrogel has attracted wide attention in the fields of chemical and biological sensing. However, it is still a challenge to integrate characteristics with low-cost, high mechanical strength, and signal self-expression into a DNA hydrogel simultaneously. Herein, a stimuli-responsive 2D photonic crystal double network DNA hydrogel (2D PhC DN-DNA hydrogel) sensing platform is developed via combining the signal self-expression of 2D PhC array with the selective recognition of polyacrylamide (PAM)/DNA DN hydrogel. The change of DNA configuration induced by specific target triggers the change of 2D PhC DN-DNA hydrogel volume, leading to a shift of the Debye diffraction ring diameter. In order to verify the feasibility of this strategy, the 2D PhC DN-DNA hydrogel with C-rich sequences is chosen as a proof-of-concept. The results indicate that the hydrogel has good detection performance for pH and Ag+/Cys. And the Debye diffraction ring diameter of the hydrogel is correlated with the concentration of the Ag+/Cys in the range of 0.5-20 µM. Compared with previously pure DNA hydrogel sensing platform, the 2D PhC DN-DNA hydrogel features low-cost preparation process and label-free determination. Meanwhile, only a laser pointer and a ruler are needed for the determination of targets, which shows that the hydrogel has application prospect in the development of portable response equipment.


Asunto(s)
Hidrogeles , Fotones , ADN/química , Hidrogeles/química
18.
Small ; 18(9): e2104681, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34914177

RESUMEN

Construction of photocatalytic systems with spatially separated dual cocatalysts is considered as a promising route to modulate charge separation/transfer, promote surface redox reactivities, and prevent unwanted reverse reactions. However, past efforts on the loading of spatially separated double-cocatalysts are limited to hollow structured semiconductors with inner/outer surface and monocrystalline semiconductors with different exposed facets. To overcome this limitation, herein, enabled by a unique stacked photocatalyst design, a facile and versatile strategy for spatial separation of redox cocatalysts on various semiconductors without structural and morphological restriction is demonstrated. The smart design begins with the deposition of light-harvesting semiconductors on reduced graphene oxide (rGO) nanosheets, followed with the coverage of Ni(OH)2 outer layer. The ternary photocatalysts exhibit superior activities and stabilities of H2 O oxidation and selective CO2 -to-CO reduction, remarkably surpassing other counterparts. The origin of the enhanced performance is attributed to the synergistic interplay of rGO@Ni(OH)2 reduction cocatalysts surrounding the semiconductors and Ni(OH)2 oxidation cocatalysts directly supported by the semiconductors, which mitigates the charge recombination, supplies highly active and selective sites for overall reactions, and preserves the semiconductors from photocorrosion. This work presents a new approach to regulating the position of dual cocatalysts and ameliorating the net efficiency of photoredox catalysis.


Asunto(s)
Dióxido de Carbono , Semiconductores , Catálisis , Oxidación-Reducción
19.
Anal Chem ; 93(34): 11887-11895, 2021 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-34398607

RESUMEN

Herein, a novel liquid crystal microarray (LCM) film with optical regulation ability is first constructed by combining liquid crystals (LC) and the highly ordered microporous structure of inverse opal photonic crystals (IOPhCs). The LCM films are fabricated by infiltrating LC molecules into the LC polymer with the structure of IOPhCs, and their properties are very different from those without the LC. Interestingly, the optical property of LCM films can be controlled by changing the orientation of LC molecules, which varies with the interfacial force. In combination with polarization images, spectral reflection peak, circular dichroism spectra, potential difference, and fluorescence images of LCM films, the mechanism of this change is investigated. It is found that the exposed basic group of single-stranded DNA is the key to the change of the optical property of LC microarrays. Meanwhile, the optical signals of LC microarrays based on the PhCs provide a novel LC signal mode for an LC sensing system (microspectral signal mode), and it can be recorded by a fiber-optic spectrometer, which is a great improvement on LC sensing signals. Therefore, the LC microarray sensing signal can be used for accurate analysis of targets by the change of the reflection peak intensity of PhCs. When the LC molecules are induced by different aptamers, the LC microarray sensing interface can be further used for the determination of different targets, such as cocaine and Hg2+. The research on LCM films is of significant value for the development of LC sensing technology and also shows great application prospects in biochemical sensing fields.


Asunto(s)
Cristales Líquidos , Análisis por Micromatrices , Óptica y Fotónica , Fotones , Refractometría
20.
Mikrochim Acta ; 188(6): 210, 2021 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-34047843

RESUMEN

A self-healing smart PhC hydrogel sensor that combines the optical property of photonic crystal and the dynamic regeneration property of boronate ester bond has been prepared for determination of glucose and related saccharides using Debye diffraction ring detection. The boronate ester bond formed through phenylboronic acid and dopamine endows the hydrogel network self-healing ability, and the tensile stress of the healing hydrogel can recover to 94.4%; this excellent self-healing property can effectively improve the reliability and lifetime of the hydrogel. Due to the high bonding capacity between 1,2- and 1,3-diol and phenylboronic acid, the hydrogel sensor has a good recognition ability for glucose and related saccharides. The reaction between the monosaccharides and the phenylboronic acid group makes the sensor swell and the diameter of the Debye diffraction ring decrease. The sensor shows good reuse and responsive ability for saccharides; the RSD of the recoverability assays is 4.3%. The determination range of the sensor to glucose is 0.5 to 12 mM. The sensor also has good response to glucose in urine, exhibiting potential application value in the preliminary screening of diabetes. Although the sensor has poor selectivity for specific monosaccharides, the process of measuring the Debye ring makes the determination no longer rely on expensive and complicated equipment and greatly simplifies the determining process and reduces the cost of determination, which shows a broad application prospect. The boronate ester bond formed through phenylboronic acid and dopamine results in the self-healing property of hydrogel network, which can effectively improve the reliability and lifetime of hydrogel. And due to the high bonding capacity between 1,2- and 1,3-diol and phenylboronic acid, the smart hydrogel sensor has a good recognition ability for glucose and related saccharides. The reaction between the monosaccharides and the phenylboronic acid group breaks the original boronate ester bond; this will lead to a decrease in cross-linking density of the PhC hydrogel sensor and further makes the sensor swell and the diameter of the Debye diffraction ring decrease.


Asunto(s)
Técnicas Biosensibles/métodos , Glucosa/análisis , Hidrogeles/química , Ácidos Borónicos/química , Fotones , Reproducibilidad de los Resultados , Rayos Ultravioleta
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