Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 112
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
PLoS Genet ; 19(7): e1010856, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37463174

RESUMO

Premature telomere shortening is a known factor correlated to idiopathic pulmonary fibrosis (IPF) occurrence, which is a chronic, progressive, age-related disease with high mortality. The etiology of IPF is still unknown. Here, we found that UBQLN1 plays a key role in telomere length maintenance and is potentially relevant to IPF. UBQLN1 involves in DNA replication by interacting with RPA1 and shuttling it off from the replication fork. The deficiency of UBQLN1 retains RPA1 at replication fork, hinders replication and thus causes cell cycle arrest and genome instability. Especially at telomere regions of the genome, where more endogenous replication stress exists because of G rich sequences, UBQLN1 depletion leads to rapid telomere shortening in HeLa cells. It revealed that UBQLN1 depletion also shortens telomere length at mouse lung and accelerates mouse lung fibrosis. In addition, the UBQLN1 expression level in IPF patients is downregulated and correlated to poor prognosis. Altogether, these results uncover a new role of UBQLN1 in ensuring DNA replication and maintaining telomere stability, which may shed light on IPF pathogenesis and prevention.


Assuntos
Fibrose Pulmonar Idiopática , Encurtamento do Telômero , Humanos , Animais , Camundongos , Encurtamento do Telômero/genética , Células HeLa , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/epidemiologia , Fibrose Pulmonar Idiopática/patologia , Homeostase do Telômero , Telômero/genética , Proteína de Replicação A/genética , Proteínas Relacionadas à Autofagia/genética , Proteínas Adaptadoras de Transdução de Sinal/genética
2.
Rapid Commun Mass Spectrom ; 38(10): e9736, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38533576

RESUMO

RATIONALE: Pesticide isomers are widely available in agricultural production and may vary widely in biological activity, potency, and toxicity. Chromatographic and mass spectrometric analysis of pesticide isomers is challenging due to structural similarities. METHODS: Based on liquid chromatography time-of-flight mass spectrometry, identification of cis-trans isomeric pesticides was achieved through retention time, characteristic fragment ions, and relative abundance ratio. Furthermore, theoretical and basic research has been conducted on the differences in characteristic fragment ions and their relative abundance ratios of cis-trans isomers. On the one hand, the cleavage pathways of six cis-trans isomers were elucidated through collision-induced dissociation to explain different fragment ions of the isomers. On the other hand, for those with the same fragment ions but different abundance ratios, energy-resolved mass spectrometry combined with computational chemical density functional theory in terms of kinetics, thermodynamics, and bond lengths was employed to explain the reasons for the differences in characteristic fragment ions and their abundance ratios. RESULTS: A high-resolution mass spectrometry method was developed for the separation and analysis of cis-trans isomers of pesticides in traditional Chinese medicine Radix Codonopsis, and six pesticide isomers were distinguished by retention time, product ions, and relative abundance ratios. The limits of quantification of the six pesticides were up to 10 µg/kg, and the linear ranges of them were 10-200 µg/kg, with coefficients of determination (R2) > 0.99, which demonstrated the good linearity of the six pesticides. The recoveries of the pesticides at spiked concentrations of 10, 20, and 100 µg/kg reached 70-120% with relative standard deviations ≤20%. CONCLUSIONS: It was demonstrated that the application of the method was well suited for accurate qualitative and quantitative analysis for isomers with different structures, which could avoid false-negative results caused by ignoring other isomers effectively.


Assuntos
Resíduos de Praguicidas , Praguicidas , Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas em Tandem/métodos , Isomerismo , Íons/análise , Resíduos de Praguicidas/análise
3.
BMC Public Health ; 24(1): 604, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38403578

RESUMO

BACKGROUND: Sedentary behavior may influence the respiratory health, but the joint effects of sedentary behavior and physical activity on pulmonary function remains poorly elucidated. We aimed to estimate the association between sedentary behavior and physical activity with pulmonary function. METHODS: A total of 12,343 participants aged 12-79 years were analyzed from the U.S. NHANES 2007-2012. Participants were categorized into 16 groups according to the cross-tabulation of sedentary behavior time (0-4.0, 4.1-8.0, 8.1-12.0, and > 12.0 h/day) and moderate or vigorous physical activity (MVPA) (0, 1-149, 150-299, and ≥ 300 min/week). Generalized linear models were used to test the association of sedentary behavior and MVPA with pulmonary function. RESULTS: Participants with sedentary behavior > 4.0 h/day were negatively related to FEV1 (forced expiratory volume in 1 s) (ß ranging from -0.015 to -0.009, p < 0.05). Compared with the reference group (0 min of MVPA and > 12.0 h/day of sedentary behavior), the negative association of sedentary behavior ≤ 8.0 h/day with FEV1 may be reduced through appropriate MVPA (ß ranging from 0.019 to 0.030, p < 0.05). For sedentary behavior > 8.0 h/day, even MVPA ≥ 300 min/week may not decrease the negative relationships. Similar results were also observed in FVC (forced vital capacity) (ß ranging from 0.018 to 0.030, p < 0.05). In participants aged ≥ 45 years, the associations were more notable. CONCLUSION: This study indicated the sedentary behavior ≤ 4.0 h/day was a relatively healthy lifestyle for pulmonary function. Only below 8.0 h/day of sedentary behavior, the negative association with pulmonary function may be reduced through appropriate MVPA.


Assuntos
Exercício Físico , Comportamento Sedentário , Humanos , Inquéritos Nutricionais , Pulmão , Estilo de Vida Saudável , Acelerometria
4.
World J Surg Oncol ; 22(1): 30, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38268018

RESUMO

OBJECTIVE: For patients with 1-2 positive sentinel lymph nodes (SLN) identified by biopsy, the necessity of axillary lymph node dissection (ALND) remains a matter of debate. The primary aim of this study was to investigate the association between postoperative pathological factors and non-sentinel lymph node (NSLN) metastases in Chinese patients diagnosed with sentinel node-positive breast cancer. METHODS: This research involved a total of 280 individuals with SLN-positive breast cancer. The relationship between postoperative pathological variables and non-sentinel lymph node metastases was scrutinized using univariate, multivariate, and stratified analysis. RESULTS: Among the 280 patients with a complete count of SLN positives, 126 (45.0%) exhibited NSLN metastasis. Within this group, 45 cases (35.71%) had 1 SLN positive, while 81 cases (64.29%) demonstrated more than 1 SLN positive. Multivariate logistic regression analysis revealed that HER2 expression status (OR 2.25, 95% CI 1.10-4.60, P = 0.0269), LVI (OR 6.08, 95% CI 3.31-11.14, P < 0.0001), and the number of positive SLNs (OR 4.17, 95% CI 2.35-7.42, P < 0.0001) were positively correlated with NSLNM. CONCLUSION: In our investigation, the risk variables for NSLN metastasis included LVI, HER2 expression, and the quantity of positive sentinel lymph nodes. However, further validation is imperative, including this institution, distinct institutions, and diverse patient populations.


Assuntos
Neoplasias da Mama , Metástase Linfática , Linfonodo Sentinela , Feminino , Humanos , Biópsia , Neoplasias da Mama/cirurgia , Linfadenopatia , Linfonodo Sentinela/cirurgia , População do Leste Asiático
5.
Chem Soc Rev ; 52(15): 5172-5254, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37462107

RESUMO

Vaccines comprising innovative adjuvants are rapidly reaching advanced translational stages, such as the authorized nanotechnology adjuvants in mRNA vaccines against COVID-19 worldwide, offering new strategies to effectively combat diseases threatening human health. Adjuvants are vital ingredients in vaccines, which can augment the degree, extensiveness, and longevity of antigen specific immune response. The advances in the modulation of physicochemical properties of nanoplatforms elevate the capability of adjuvants in initiating the innate immune system and adaptive immunity, offering immense potential for developing vaccines against hard-to-target infectious diseases and cancer. In this review, we provide an essential introduction of the basic principles of prophylactic and therapeutic vaccination, key roles of adjuvants in augmenting and shaping immunity to achieve desired outcomes and effectiveness, and the physiochemical properties and action mechanisms of clinically approved adjuvants for humans. We particularly focus on the preclinical and clinical progress of highly immunogenic emerging nanotechnology adjuvants formulated in vaccines for cancer treatment or infectious disease prevention. We deliberate on how the immune system can sense and respond to the physicochemical cues (e.g., chirality, deformability, solubility, topology, and chemical structures) of nanotechnology adjuvants incorporated in the vaccines. Finally, we propose possible strategies to accelerate the clinical implementation of nanotechnology adjuvanted vaccines, such as in-depth elucidation of nano-immuno interactions, antigen identification and optimization by the deployment of high-dimensional multiomics analysis approaches, encouraging close collaborations among scientists from different scientific disciplines and aggressive exploration of novel nanotechnologies.

6.
Int J Mol Sci ; 25(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38339157

RESUMO

YTH N6-methyladenosine RNA binding protein 1 (YTHDF1), an m6A reader, has a role in the development and progression of breast cancer as well as the immunological microenvironment. The networks of competing endogenous RNA in cancer have received much attention in research. In tumor gene therapy, the regulatory networks of m6A and competing endogenous RNA are increasingly emerging as a new route. We evaluated the relationship between the YTHDF1 expression, overall survival, and clinicopathology of breast cancer using TCGA, PrognoScan, and other datasets. We used Western blot to demonstrate that YTHDF1 is substantially expressed in breast cancer tissues. Furthermore, we explored YTHDF1's functions in the tumor mutational burden, microsatellite instability, and tumor microenvironment. Our findings indicate that YTHDF1 is a critical component of the m6A regulatory proteins in breast cancer and may have a particular function in the immunological microenvironment. Crucially, we investigated the relationship between YTHDF1 and the associated competitive endogenous RNA regulatory networks, innovatively creating three such networks (Dehydrogenase/Reductase 4-Antisense RNA 1-miR-378g-YTHDF1, HLA Complex Group 9-miR-378g-YTHDF1, Taurine Up-regulated 1-miR-378g-YTHDF1). Furthermore, we showed that miR-378g could inhibit the expression of YTHDF1, and that miR-378g/YTHDF1 could impact MDA-MB-231 proliferation. We speculate that YTHDF1 may serve as a biomarker for poor prognosis and differential diagnosis, impact the growth of breast cancer cells via the ceRNA network axis, and be a target for immunotherapy against breast cancer.


Assuntos
Neoplasias da Mama , MicroRNAs , Proteínas de Ligação a RNA , Humanos , Western Blotting , MicroRNAs/genética , Neoplasias , RNA Antissenso , RNA Endógeno Competitivo/genética , RNA Endógeno Competitivo/metabolismo , Proteínas de Ligação a RNA/genética , Microambiente Tumoral/genética , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo
7.
J Am Chem Soc ; 145(46): 25274-25282, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37938914

RESUMO

The decoration of 2D nanostructures using heteroepitaxial growth is of great importance to achieve functional assemblies employed in biomedical, electrical, and mechanical applications. Although the functionalization of polymers before self-assembly has been investigated, the exploration of direct surface modification in the third dimension from 2D nanostructures has, to date, been unexplored. Here, we used living crystallization-driven self-assembly to fabricate poly(ε-caprolactone)-based 2D platelets with controlled size. Importantly, surface modification of the platelets in the third dimension was achieved by using functional monomers and light-induced polymerization. This method allows us to selectively regulate the height and fluorescence properties of the nanostructures. Using this approach, we gained unprecedented spatial control over the surface functionality in the specific region of complex 2D platelets.

8.
Small ; 19(50): e2304353, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37620125

RESUMO

Fiber-shaped conductors with high electrical conductivity, stretchability, and durability have attracted increasing attention due to their potential for integration into arbitrary wearable forms. However, these fiber conductors still suffer from low reliability and short life span, particularly in harsh environments. Herein, a conductive, environment-tolerant, stretchable, and healable fiber conductor (CESH), which consists of a self-healable and stretchable organohydrogel fiber core, a conductive and buckled silver nanowire coating, and a self-healable and waterproof protective sheath, is reported. Such a multilayer core-sheath design not only offers high stretchability (≈2400%), high electrical conductivity (1.0 × 106 S m-1 ), outstanding self-healing ability and durability, but also possesses unprecedented tolerance in harsh environments including wide working temperature (-60-20 °C), arid (≈10 % RH (RH: room humidity)), and underwater conditions. As proof-of-concept demonstrations, CESHs are integrated into various wearable formats as interconnectors to steadily perform the electric function under different mechanical deformations and harsh conditions. Such a new type of multifunctional fiber conductors can bridge the gap in stretchable and self-healing fiber technologies by providing ultrastable electrical conductance and excellent environmental tolerance, which can greatly expand the range of applications for fiber conductors.

9.
Biomacromolecules ; 24(2): 1032-1041, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36700709

RESUMO

Two-dimensional, size-tunable, water-dispersible particle micelles with spatially defined chemistries can be obtained by using "living" crystallization-driven self-assembly (CDSA) approach. Nevertheless, a major obstacle of crystalline particles in drug delivery application is the difficulty in accessing to cargo within crystalline cores. In the present work, we design four different types of biocompatible two-dimensional platelets with a crystalline poly(ε-caprolactone) (PCL) core, a hydrophobic poly(4-vinylprydine) (P4VP) segment, and a water dispersible poly(N,N-dimethyl acrylamide) (PDMA) block in ethanol by seeded growth method. Transferring those uniform platelets with tailored compositions to an aqueous solution in the presence of a hydrophobic drug leads to efficient encapsulation of the cargo in the P4VP segments via hydrophobic interactions. These drug-loaded platelets exhibit pH-responsive release behavior in aqueous media due to the protonated-deprotonated process of P4VP blocks in acidic and neutral solutions. This work provides initial insight into biocompatible PCL platelets with low dispersity and precise chemistry control in stimulus-responsive drug delivery fields.


Assuntos
Plaquetas , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Micelas , Água/química , Concentração de Íons de Hidrogênio , Portadores de Fármacos/química , Poliésteres/química , Tamanho da Partícula , Polietilenoglicóis/química
10.
Future Oncol ; 19(27): 1853-1863, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37593839

RESUMO

Aim: This study was designed to investigate the prognostic value of the platelet volume index in patients with invasive breast cancer (IBC). Methods: A total of 524 patients with IBC were enrolled in this study, with a median follow-up time of 6.76 years. The relationship between platelet volume indices and breast cancer prognosis was analyzed. Results: There is a strong correlation between a higher platelet distribution width-to-platelet count ratio (PDW/P) and poorer disease-free survival (DFS) in patients with IBC. The DFS rate was significantly lower among individuals with elevated PDW/P ratios compared with those with lower ratios. Conclusion: The PDW/P ratio is an independent risk factor for predicting DFS in patients with IBC.

11.
World J Surg Oncol ; 21(1): 386, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097994

RESUMO

BACKGROUND: A connection between lymphovascular invasion and axillary lymph node metastases in breast cancer has been observed, but the findings are inconsistent and primarily based on research in Western populations. We investigated the association between lymphovascular invasion and non-sentinel lymph node (non-SLN) metastasis in breast cancer patients with sentinel lymph node (SLN) metastasis in western China. METHODS: This study comprised 280 breast cancer patients who tested positive for SLN through biopsy and subsequently underwent axillary lymph node dissection (ALND) at The People's Hospital of Guangxi Zhuang Autonomous Region between March 2013 and July 2022. We used multivariate logistic regression analyses to assess the association between clinicopathological characteristics and non-SLN metastasis. Additionally, we conducted further stratified analysis. RESULTS: Among the 280 patients with positive SLN, only 126 (45%) exhibited non-SLN metastasis. Multivariate logistic regression demonstrated that lymphovascular invasion was an independent risk factor for non-SLN in breast cancer patients with SLN metastasis (OR = 6.11; 95% CI, 3.62-10.32, p < 0.05). The stratified analysis yielded similar results. CONCLUSIONS: In individuals with invasive breast cancer and 1-2 positive sentinel lymph nodes, lymphovascular invasion is the sole risk factor for non-SLN metastases. This finding aids surgeons and oncologists in devising a plan for local axillary treatment, preventing both over- and undertreatment.


Assuntos
Neoplasias da Mama , Linfadenopatia , Linfonodo Sentinela , Humanos , Feminino , Linfonodo Sentinela/cirurgia , Linfonodo Sentinela/patologia , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Biópsia de Linfonodo Sentinela/métodos , Estudos Transversais , Linfonodos/cirurgia , Linfonodos/patologia , China , Excisão de Linfonodo , Metástase Linfática/patologia , Fatores de Risco , Linfadenopatia/patologia , Axila/patologia
12.
World J Surg Oncol ; 21(1): 125, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024930

RESUMO

BACKGROUND: The randomized trials which include ACOSOG Z0011 and IBCSG 23-01 had found that the survival rates were not different in patients with cT1/2N0 and 1-2 sentinel lymph node (SLN)-positive, macro/micrometastases who underwent breast-conserving therapy, and micrometastases who underwent total mastectomy (TM), when axillary lymph node dissection (ALND) was omitted. However, for patients with cT1/2N0 and 1-2 SLN macrometastases who underwent TM; there was still insufficient evidence from clinical studies to support whether ALND can be exempted. This study aimed to investigate the risk factors of non-sentinel lymph node (nSLN) metastasis in breast cancer patients with 1-2 SLN macrometastases undergoing TM. METHODS: The clinicopathological data of 1491 breast cancer patients who underwent TM and SLNB from January 2017 to February 2022 were retrospectively analyzed. Univariate and multivariate analyses were performed to analyze the risk factors for nSLN metastasis. RESULTS: A total of 273 patients with 1-2 SLN macrometastases who underwent TM were enrolled. Postoperative pathological data showed that 35.2% patients had nSLN metastasis. The results of multivariate analysis indicated that tumor size (TS) (P = 0.002; OR: 1.051; 95% CI: 1.019-1.084) and ratio of SLN macrometastases (P = 0.0001; OR: 12.597: 95% CI: 4.302-36.890) were the independent risk factors for nSLN metastasis in breast cancer patients with 1-2 SLN macrometastases that underwent TM. The ROC curve analysis suggested that when TS ≤22 mm and ratio of SLN macrometastases ≤0.33, the incidence of nSLN metastasis could be reduced to 17.1%. CONCLUSIONS: The breast cancer patients with cT1/2N0 stage, undergoing TM and 1-2 SLN macrometastases, when the TS ≤22 mm and macrometastatic SLN does not exceed 1/3 of the total number of detected SLN, the incidence of nSLN metastasis is significantly reduced, but whether ALND can be exempted needs further exploration.


Assuntos
Neoplasias da Mama , Linfonodo Sentinela , Humanos , Feminino , Neoplasias da Mama/patologia , Biópsia de Linfonodo Sentinela/métodos , Metástase Linfática/patologia , Estudos de Casos e Controles , Mastectomia Simples , Estudos Retrospectivos , Micrometástase de Neoplasia/patologia , Mastectomia , Axila/patologia , Linfonodo Sentinela/cirurgia , Linfonodo Sentinela/patologia , Excisão de Linfonodo/métodos , Fatores de Risco , Linfonodos/cirurgia , Linfonodos/patologia
13.
Nano Lett ; 22(7): 3003-3010, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35357200

RESUMO

DNA-based Boolean logic computing has emerged as a leading technique in biosensing, diagnosis, and therapeutics. Due to the development of the biological and chemical methods, especially the toehold-mediated DNA strand displacement (TMSD) reaction, different logic gates as well as circuits can be performed. However, most of these methods have been conducted at the bulk level, which may lead to missing information and be less controllable. Herein, we engineered single-molecule DNA computing controlled by stretching forces using magnetic tweezers. By tracking the real-time signals of the DNA extension, the output can be determined at a single base-pair resolution. A kinetics-controllable TMSD reaction was realized in the range of a ∼19-fold change of the reaction rate by different stretching forces. OR, AND, and NOT gates were also achieved. In addition, resettable DNA computing using force stretching cycles has been further exemplified. Overall, such a real-time, label-free, and force-controlled single-molecule DNA computing system provided new insight into molecular computing.


Assuntos
DNA , Lógica , DNA/química , Fenômenos Magnéticos , Magnetismo
14.
Angew Chem Int Ed Engl ; 62(50): e202309160, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37653555

RESUMO

Reactive X species (RXS), encompassing elements such as O, N, C, S, Se, Cl, Br, I, and H, play vital roles in cell biology and physiological function, impacting cellular signal transduction, metabolic regulation, and disease processes. The redox unbalance of RXS is firmly implicated in an assortment of physiological and pathological disorders, including cancer, diabetes, cardiovascular disease, and neurodegenerative diseases. However, the intricate nature and multifactorial dependence of RXS pose challenges in comprehending and precisely modulating their biological behavior. Nanomaterials with distinct characteristics and biofunctions offer promising avenues for generating or scavenging RXS to maintain redox homeostasis and advance disease therapy. This minireview provides a tutorial summary of the relevant chemistry and specific mechanisms governing different RXS, focusing on cellular metabolic regulation, stress responses, and the role of nanomedicine in RXS generation and elimination. The challenges associated with chemically regulating RXS for diverse disease treatments are further discussed along with the future prospects, aiming to facilitate the clinical translation of RXS-based nanomedicine and open new avenues for improved therapeutic interventions.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Nanomedicina , Oxirredução , Neoplasias/patologia , Homeostase , Espécies Reativas de Oxigênio/metabolismo
15.
J Am Chem Soc ; 144(27): 12290-12298, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35763425

RESUMO

This work showcases chiral complementarity in aromatic stacking interactions as an effective tool to optimize the chiroptical and electrochemical properties of perylene diimides (PDIs). PDIs are a notable class of robust dye molecules and their rich photo- and electrochemistry and potential chirality make them ideal organic building blocks for chiral optoelectronic materials. By exploiting the new bay connectivity of twisted PDIs, a dynamic bis-PDI macrocycle (the "Pink Box") is realized in which homochiral PDI-PDI π-π stacking interactions are switched on exclusively. Using a range of experimental and computational techniques, we uncover three important implications of the macrocycle's chiral complementarity for PDI optoelectronics. First, the homochiral intramolecular π-π interactions anchor the twisted PDI units, yielding enantiomers with half-lives extended over 400-fold, from minutes to days (in solution) or years (in the solid state). Second, homochiral H-type aggregation affords the macrocycle red-shifted circularly polarized luminescence and one of the highest dissymmetry factors of any small organic molecule in solution (glum = 10-2 at 675 nm). Finally, excellent through-space PDI-PDI π-orbital overlap stabilizes PDI reduced states, akin to covalent functionalization with electron-withdrawing groups.


Assuntos
Perileno , Eletroquímica , Elétrons , Perileno/química , Estereoisomerismo
16.
Macromol Rapid Commun ; 43(19): e2200281, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35575627

RESUMO

Tailoring the mechanical properties has always been a key to the field of hydrogels in terms of different applications. Particularly, DNA hydrogels offer an unambiguous way to precisely tune the mechanical properties, largely on account of their programmable sequences, abundant responding toolbox, and various ligation approaches. In this review, DNA hydrogels from the perspective of mechanical properties, from a synthetic standpoint to different applications, are introduced. The relationship between the structure and their mechanical properties in DNA hydrogels and the methods of regulating the mechanical properties of DNA hydrogels are specifically summarized. Furthermore, several recent applications of DNA hydrogels in relation to their mechanical properties are discussed. Benefiting from the tunability and flexibility, rational design of mechanical properties in DNA hydrogels provided unheralded interest from fundamental science to extensive applications.


Assuntos
DNA , Hidrogéis , DNA/química , Hidrogéis/química
17.
J Sep Sci ; 45(14): 2520-2528, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35569141

RESUMO

A novel method for detecting pesticide multi-residue in grass forage (alfalfa and oat) was established based on the one-step automatic extraction and purification technology of quick, easy, cheap, effective, rugged, and safe combined with ultrahigh-performance liquid chromatography quadrupole Orbitrap high-resolution mass spectrometry. The crushed sample was extracted with acetonitrile with 1% acetate, followed by a cleanup step with a primary-secondary amine, octadecylsilane, and graphitized carbon black. The extraction and purification were carried out using the one-step automatic pretreatment equipment. The target pesticides were acquired in positive ion electrospray ionization mode and full scan/data dependent secondary scan mode. The calibration curve shows good linearity over the corresponding concentration range, with the coefficient of determination greater than 0.99. The screening detection limits were 0.5-50 µg/kg, and the limit of quantification for the 206 pesticides was set at 1-50 µg/kg. At the spiking levels of one, two, and 10 times of limit of quantification, more than 95% of pesticides had recovery between 70-120%, with a relative standard deviation ≤20%. The method was proved to be simple, rapid, high-sensitivity, and could be routinely used for the high throughput screening and quantitative analysis of pesticide residues in alfalfa and oat.


Assuntos
Resíduos de Praguicidas , Praguicidas , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Praguicidas/análise , Poaceae
18.
Am J Perinatol ; 39(9): 1015-1019, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-33285607

RESUMO

OBJECTIVE: Despite known benefits, the timing of and method used for umbilical cord clamping (UCC) in neonates remain controversial in China, as well as internationally. The objective of this study was to assess knowledge, attitudes, and practice of UCC amongst health care providers in China, as recommended by medical professional organizations. STUDY DESIGN: A web-based questionnaire on cord clamping practices was administered to midwives, obstetricians, and neonatologists in 126 hospitals from 16 provinces. The provinces were selected from seven different regions of China. RESULTS: A total of 5,005 (60.5% of eligible respondents) health care providers returned completed questionnaires. The awareness rates for immediate cord clamping (ICC) and delayed cord clamping (DCC) were over 85%, but the implementation rate for DCC was relatively low (ICC 58.3% vs. DCC 41.6%). Most neonates were placed below the introitus (92.8%) during cord clamping and this correlated with the route of delivery. The choice of UCC was impelled by different factors. Benefits for neonates influenced the choice of ICC (50%) and promoting a larger blood volume to stabilize systemic circulation influenced the choice of DCC (92.3%). Majority (91.5%) of respondents acquiesced that it was necessary to develop national clinical guidelines for UCC. CONCLUSION: The majority of obstetricians, neonatologists, and midwives who participated in this study had a positive perception of DCC. However, this did not translate to daily practice. The practice of UCC is variable and there are no standard guidelines. KEY POINTS: · The first large-scale epidemiological investigation of umbilical cord ligation is in China.. · The survey included three commonly used umbilical cord clamping methods.. · The respondents included neonatologists..


Assuntos
Parto Obstétrico , Clampeamento do Cordão Umbilical , Constrição , Parto Obstétrico/métodos , Feminino , Humanos , Recém-Nascido , Gravidez , Fatores de Tempo , Cordão Umbilical/cirurgia
19.
Am J Perinatol ; 39(1): 31-36, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32620024

RESUMO

OBJECTIVE: This study aimed to investigate whether umbilical cord milking (UCM) prevents and controls anemia in preterm infants, as compared with immediate cord clamping (ICC). STUDY DESIGN: Pregnant women delivering at <34 weeks' gestation in four hospitals were randomly assigned to undergo UCM or ICC from July 2017 to June 2019. Hematological parameters and iron status were collected and analyzed as primary outcomes at 24 hours, 1 week, 2 weeks, and 6 months after delivery. RESULTS: Neonates receiving UCM had significant higher levels of hemoglobin (Hb), hematocrit, and serum iron (p < 0.05). Lower prevalence of anemia and lower need for transfusions were noted in UCM group. Although UCM was associated with prolonged duration of phototherapy, the maximum levels of bilirubin were similar between two groups (p > 0.05). CONCLUSION: UCM is an effective intervention to help preterm infants experience less anemia with the potential to increase blood volume, as seen by higher Hb levels and more enhanced iron stores.


Assuntos
Anemia/prevenção & controle , Doenças do Prematuro/prevenção & controle , Recém-Nascido Prematuro , Clampeamento do Cordão Umbilical , Bilirrubina/sangue , Feminino , Hematócrito , Hemoglobinas/análise , Humanos , Hiperbilirrubinemia Neonatal/terapia , Recém-Nascido , Recém-Nascido Prematuro/sangue , Ferro/sangue , Masculino , Fatores de Tempo
20.
Sensors (Basel) ; 22(17)2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-36080939

RESUMO

Accurate identification of the degradation stage is key to the prediction of the remaining useful life (RUL) of bearings. The 3σ method is commonly used to identify the degradation point. However, the recognition accuracy is seriously disturbed by the random outliers in the normal stage. Therefore, this paper proposes an adaptive recognition method for the degradation stage based on outlier cleaning. Firstly, an improved multi-scale kernel regression outlier detection method is adopted to roughly search the abnormal signal segments. Then, a method for the accurate locating of the start and end points of abnormal impulses is established. After that, indexes are constructed for screening abnormal segments and an iterative strategy is proposed to achieve an accurate and efficient removal of abnormal impulses. After outlier cleaning, the 3σ approach is used to set the degradation warning threshold adaptively to realize the degradation stage recognition of the bearings. The PHM 2012 rotating machinery dataset is used to verify the effectiveness of the proposed method. Experimental results show that the proposed method can accurately locate and remove the outliers adaptively. After the cleaning of the outliers, the identification of the degradation stage is no longer disturbed by the selection of the reference signal of the normal stage and the robustness and the accuracy of the degradation stage identification have been improved significantly.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA