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1.
Cardiovasc Diabetol ; 23(1): 3, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172813

RESUMO

BACKGROUND: The triglyceride-glucose (TyG) index has been proposed as a surrogate marker of insulin resistance. However, the relationship between the TyG index and central blood pressure (BP), has not been well studied in adults. METHODS: A total of 715 Chinese adult participants were enrolled in this study. Anthropometric and BP were assessed. The TyG index was calculated as ln[fasting triglycerides(mg/dL) × fasting glucose(mg/dL)/2]. Central BP was measured using SphygmoCor system. RESULTS: The participants were stratified into three groups based on the TyG index, and significant differences were observed in metabolic and cardiovascular parameters and the prevalence of hypertension among the groups. Both brachial (ß = 1.38, P = 0.0310; group highest vs. lowest, ß = 2.66, P = 0.0084) and aortic (ß = 2.38, P = 0.0002; group highest vs. lowest, ß = 3.96, P = 0.0001) diastolic BP were significantly and independently associated with the TyG index and increasing TyG index tertile. However, there was no independent association between the TyG index and systolic BP. A one-unit increase in the TyG index was associated with a 46% higher risk of hypertension (P = 0.0121), and compared with the lowest group, participants in the highest group had a 95% higher risk of hypertension (P = 0.0057). CONCLUSIONS: Our study demonstrates a significant and independent association between the TyG index and both brachial and aortic diastolic BP in Chinese adults. Furthermore, the TyG index was found to be an independent predictor of hypertension.


Assuntos
Hipertensão , Resistência à Insulina , Adulto , Humanos , Glucose/metabolismo , Glicemia/metabolismo , Triglicerídeos , Pressão Sanguínea , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Biomarcadores , China/epidemiologia , Fatores de Risco
2.
Toxicol Appl Pharmacol ; 483: 116839, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38290667

RESUMO

Actin filaments form unique structures with robust actin bundles and cytoskeletal networks affixed to the extracellular matrix and interact with neighboring cells, which are crucial structures for cancer cells to acquire a motile phenotype. This study aims to investigate a novel antitumor mechanism by which Tanshinone IIA (Tan IIA) modulates the morphology and migration of liver cancer cells via actin cytoskeleton regulation. 97H and Huh7 exhibited numerous tentacle-like protrusions that interacted with neighboring cells. Following treatment with Tan IIA, 97H and Huh7 showed a complete absence of cytoplasmic protrusion and adherens junctions, thereby effectively impeding their migration capability. The fluorescence staining of F-actin and microtubules indicated that these tentacle-like protrusions and cell-cell networks were actin-based structures that led to morphological changes after Tan IIA treatment by retracting and reorganizing beneath the membrane. Tan IIA can reverse the actin depolymerization and cell morphology alterations induced by latrunculin A. Tan IIA down-regulated actin and Rho GTPases expression significantly, as opposed to inducing Rho signaling activation. Preventing the activity of proteasomes and lysosomes had no discernible impact on the modifications in cellular structure and protein expression induced by Tan IIA. However, as demonstrated by the puromycin labeling technique, the newly synthesized proteins were significantly inhibited by Tan IIA. In conclusion, Tan IIA can induce dramatic actin cytoskeleton remodeling by inhibiting the protein synthesis of actin and Rho GTPases, resulting in the suppression of tumor growth and migration. Targeting the actin cytoskeleton of Tan IIA is a promising strategy for HCC treatment.


Assuntos
Abietanos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Actinas , Proteínas rho de Ligação ao GTP/farmacologia , Proliferação de Células , Carcinoma Hepatocelular/tratamento farmacológico , Citoesqueleto , Citoesqueleto de Actina , Linhagem Celular Tumoral , Apoptose
3.
Arch Microbiol ; 206(4): 164, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483645

RESUMO

Refined indigenous Saccharomyces cerevisiae can enhance refinement, sophistication, and subtlety of fruit wines by showcasing exceptional regional characteristics. In order to identify exceptional indigenous S. cerevisiae strains from Yunnan olive, this study isolated 60 yeast strains from wild Yunnan olive fermentation mash. The five S. cerevisiae strains were subjected to morphological and molecular biological identification, followed by evaluation of their fermentation performance, ethanol production capacity, ester production capacity, H2S production capacity, killing capacity, and tolerance. Strains LJM-4, LJM-10, and LJM-26 exhibited robust tolerance to 6% ethanol volume fraction, pH 2.8, sucrose concentration of 400 g/L, SO2 concentration of 0.3 g/L, glucose concentration of 400 g/L at both 40 °C and 15 °C. Additionally, strain LJM-10 demonstrated a faster fermentation rate compared to the other strains. Among the tested S. cerevisiae strains evaluated in this study for olive wine fermentation process in Yunnan region; strain LJM-10 displayed superior abilities in terms of ester and ethanol production while exhibiting the lowest H2S production levels. These findings suggest that strain LJM-10 holds great potential as an excellent candidate for optimizing fruit wine S. cerevisiae fermentation processes in Yunnan olive fruit wine.


Assuntos
Olea , Vinho , Saccharomyces cerevisiae/genética , Fermentação , China , Vinho/análise , Etanol/análise , Ésteres
4.
Arch Microbiol ; 206(6): 279, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38805051

RESUMO

Yeast, which plays a pivotal role in the brewing, food, and medical industries, exhibits a close relationship with human beings. In this study, we isolated and purified 60 yeast strains from the natural fermentation broth of Sidamo coffee beans to screen for indigenous beneficial yeasts. Among them, 25 strains were obtained through morphological characterization on nutritional agar medium from Wallerstein Laboratory (WL), with molecular biology identifying Saccharomyces cerevisiae strain YBB-47 and the remaining 24 yeast strains identified as Pichia kudriavzevii. We investigated the fermentation performance, alcohol tolerance, SO2 tolerance, pH tolerance, sugar tolerance, temperature tolerance, ester production capacity, ethanol production capacity, H2S production capacity, and other brewing characteristics of YBB-33 and YBB-47. The results demonstrated that both strains could tolerate up to 3% alcohol by volume at a high sucrose mass concentration (400 g/L) under elevated temperature conditions (40 ℃), while also exhibiting a remarkable ability to withstand an SO2 mass concentration of 300 g/L at pH 3.2. Moreover, S. cerevisiae YBB-47 displayed a rapid gas production rate and strong ethanol productivity. whereas P. kudriavzevii YBB-33 exhibited excellent alcohol tolerance. Furthermore, this systematic classification and characterization of coffee bean yeast strains from the Sidamo region can potentially uncover additional yeasts that offer high-quality resources for industrial-scale coffee bean production.


Assuntos
Etanol , Fermentação , Pichia , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/isolamento & purificação , Pichia/metabolismo , Pichia/isolamento & purificação , Pichia/genética , Pichia/classificação , Etanol/metabolismo , Concentração de Íons de Hidrogênio , Café/microbiologia , Coffea/microbiologia , Temperatura , Sementes/microbiologia , Sulfeto de Hidrogênio/metabolismo
5.
Mol Cell Biochem ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409514

RESUMO

This study aimed to decipher the mechanism of circular ribonucleic acids (circRNAs) in lower extremity arteriosclerosis obliterans (LEASO). First, bioinformatics analysis was performed for screening significantly down-regulated cardiac specific circRNA-circHAT1 in LEASO. The expression of circHAT1 in LEASO clinical samples was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The protein expression of splicing factor arginine/serine-rich 1 (SFRS1), α-smooth muscle actin (α-SMA), Calponin (CNN1), cyclin D1 (CNND1) and smooth muscle myosin heavy chain 11 (SMHC) in vascular smooth muscle cells (VSMCs) was detected by Western blotting. Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU) and Transwell assays were used to evaluate cell proliferation and migration, respectively. RNA immunoprecipitation (RNA-IP) and RNA pulldown verified the interaction between SFRS1 and circHAT1. By reanalyzing the dataset GSE77278, circHAT1 related to VSMC phenotype conversion was screened, and circHAT1 was found to be significantly reduced in peripheral blood mononuclear cells (PBMCs) of LEASO patients compared with healthy controls. Knockdown of circHAT1 significantly promoted the proliferation and migration of VSMC cells and decreased the expression levels of contractile markers. However, overexpression of circHAT1 induced the opposite cell phenotype and promoted the transformation of VSMCs from synthetic to contractile. Besides, overexpression of circHAT1 inhibited platelet-derived growth factor-BB (PDGF-BB)-induced phenotype switch of VSMC cells. Mechanistically, SFRS1 is a direct target of circHAT1 to mediate phenotype switch, proliferation and migration of VSMCs. Overall, circHAT1 regulates SFRS1 to inhibit the cell proliferation, migration and phenotype switch of VSMCs, suggesting that it may be a potential therapeutic target for LEASO.

6.
Eur Radiol ; 34(2): 917-927, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37610440

RESUMO

OBJECTIVES: To develop an end-to-end deep neural network for the classification of contrast-enhanced mammography (CEM) images to facilitate breast cancer diagnosis in the clinic. METHODS: In this retrospective mono-centric study, patients who underwent CEM examinations from January 2019 to August 2021 were enrolled. A multi-feature fusion network combining low-energy (LE) and dual-energy subtracted (DES) images and dual view, as well as bilateral information, was trained and tested using a large CEM dataset with a diversity of breast tumors for breast lesion classification. Its generalization performance was further evaluated on two external datasets. Results were reported using AUC, accuracy, sensitivity, and specificity. RESULTS: A total of 2496 patients (mean age, 53 years ± 12 (standard deviation)) were included and divided into a training set (1718), a validation set (255), and a testing set (523). The proposed CEM-based multi-feature fusion network achieved the best diagnosis performance with an AUC of 0.96 (95% confidence interval (CI): 0.95, 0.97), compared with the no-fusion model, the left-right fusion model, and the multi-feature fusion network with only LE image inputs. Our models reached an AUC of 0.90 (95% CI: 0.85, 0.94) on a full-field digital mammograph (FFDM) external dataset (86 patients), and an AUC of 0.92 (95% CI: 0.89, 0.95) on a CEM external dataset (193 patients). CONCLUSION: The developed multi-feature fusion neural network achieved high performance in CEM image classification and was able to facilitate CEM-based breast cancer diagnosis. CLINICAL RELEVANCE STATEMENT: Compared with low-energy images, CEM images have greater sensitivity and similar specificity in malignant breast lesion detection. The multi-feature fusion neural network is a promising computer-aided diagnostic tool for the clinical diagnosis of breast cancer. KEY POINTS: • Deep convolutional neural networks have the potential to facilitate contrast-enhanced mammography-based breast cancer diagnosis. • The multi-feature fusion neural network reaches high accuracies in the classification of contrast-enhanced mammography images. • The developed model is a promising diagnostic tool to facilitate clinical breast cancer diagnosis.


Assuntos
Neoplasias da Mama , Humanos , Pessoa de Meia-Idade , Feminino , Neoplasias da Mama/diagnóstico por imagem , Estudos Retrospectivos , Mamografia/métodos , Mama/diagnóstico por imagem , Redes Neurais de Computação
7.
Inorg Chem ; 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38946199

RESUMO

The functionalization of polyoxovanadate clusters is promising but of great challenge due to the versatile coordination geometry and oxidation state of vanadium. Here, two unprecedented silsesquioxane ligand-protected "fully reduced" polyoxovanadate clusters were fabricated via a facial solvothermal methodology. The initial mixture of the two polyoxovanadate clusters with different colors and morphologies (green plate V14 and blue block V6) was successfully separated as pure phases by meticulously controlling the assembly conditions. Therein, the V14 cluster is the highest-nuclearity V-silsesquioxane cluster to date. Moreover, the transformation from a dimeric silsesquioxane ligand-protected V14 cluster to a cyclic hexameric silsesquioxane ligand-protected V6 cluster was also achieved, and the possible mechanism termed "ligand-condensation-involved dissociation reassembly" was proposed to explain this intricate conversion process. In addition, the robust V6 cluster was served as a heterogeneous catalyst for the synthesis of important heterocyclic compounds, quinazolinones, starting from 2-aminobenzamide and aldehydes. The V6 cluster exhibits high activity and selectivity to access pure quinazolinones under mild conditions, where the high selectivity was attributed to the confinement effect of the macrocyclic silsesquioxane ligand constraining the molecular freedom of the reaction species. The stability and recyclability as well as the tolerance of a wide scope of aldehyde substrates endow the V6 cluster with a superior performance and appreciable potential in catalytic applications.

8.
Transfus Apher Sci ; 63(3): 103938, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38678984

RESUMO

OBJECTIVE: This study aims to report two unrelated individuals with the same novel CisAB blood type and confirm this rare blood type using a comprehensive approach that combines serological and molecular biology techniques. METHODS: Peripheral blood samples were collected from two patients and their family members. ABO blood typing and antibody detection were performed using conventional tube methods. Molecular biology techniques were employed to amplify and sequence the 6th and 7th exons of the ABO gene, with reference to gene mutation databases provided by NCBI and ISBT. RESULTS: The genotypes of the two unrelated individuals were identical and were confirmed as a new genotype through ISBT gene database comparison. Serological testing results showed different antigen reaction patterns, especially in terms of reverse typing. Gene sequencing identified a series of mutation points, and both unrelated individuals and one of their daughters had mutations at 297 A>G, 526 C>G, 657 C>T, 703 G>A, 803 G>C, and 930 G>A. According to the comprehensive results from The Blood Group Antigen Gene Mutation Database provided by NCBI, the genotype was determined as Bw37. However, based on the results from Names for ABO (ISBT 001) blood group alleles v1.1 171023, the sequencing results indicated a novel mutation combination not found in the ISBT database. Considering the serological reactions of all three individuals, the final determination was CisAB. CONCLUSIONS: This study confirmed the novel CisAB blood type in two individuals through the comprehensive application of serology and molecular biology techniques. The identified gene mutation points were not recorded in known databases, emphasizing the uniqueness of CisAB blood types. This research provides important insights into the genetic basis of ABO subtypes and the characteristics of CisAB blood types, and the relevant results have been submitted to the ISBT website for further research.


Assuntos
Sistema ABO de Grupos Sanguíneos , Humanos , Sistema ABO de Grupos Sanguíneos/genética , Feminino , Masculino , Tipagem e Reações Cruzadas Sanguíneas/métodos , Adulto , Genótipo
9.
Mol Cell ; 64(4): 673-687, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27840030

RESUMO

Distinctive from their normal counterparts, cancer cells exhibit unique metabolic dependencies on glutamine to fuel anabolic processes. Specifically, pancreatic ductal adenocarcinoma (PDAC) cells rely on an unconventional metabolic pathway catalyzed by aspartate aminotransferase, malate dehydrogenase 1 (MDH1), and malic enzyme 1 to rewire glutamine metabolism and support nicotinamide adenine dinucleotide phosphate (NADPH) production. Here, we report that methylation on arginine 248 (R248) negatively regulates MDH1. Protein arginine methyltransferase 4 (PRMT4/CARM1) methylates and inhibits MDH1 by disrupting its dimerization. Knockdown of MDH1 represses mitochondria respiration and inhibits glutamine metabolism, which sensitizes PDAC cells to oxidative stress and suppresses cell proliferation. Meanwhile, re-expression of wild-type MDH1, but not its methylation-mimetic mutant, protects cells from oxidative injury and restores cell growth and clonogenic activity. Importantly, MDH1 is hypomethylated at R248 in clinical PDAC samples. Our study reveals that arginine methylation of MDH1 by CARM1 regulates cellular redox homeostasis and suppresses glutamine metabolism of pancreatic cancer.


Assuntos
Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Glutamina/metabolismo , Malato Desidrogenase (NADP+)/genética , Neoplasias Pancreáticas/genética , Proteína-Arginina N-Metiltransferases/genética , Arginina/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células , Células HEK293 , Humanos , Malato Desidrogenase (NADP+)/antagonistas & inibidores , Malato Desidrogenase (NADP+)/metabolismo , Metilação , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Modelos Moleculares , NADP/biossíntese , Oxirredução , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Multimerização Proteica , Estrutura Secundária de Proteína , Proteína-Arginina N-Metiltransferases/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais
10.
Clin Lab ; 70(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38469785

RESUMO

BACKGROUND: The aim was to analyze the serological and molecular genetic characteristics of a rare B(A) subtype pedigree, explore its pathogenesis, and discuss transfusion strategies. METHODS: ABO blood typing serological tests were conducted on a female subject and her family member using standard serological methods. Sequencing analysis of the ABO gene exons 6 and 7 was performed using PCR technique for the female subject and her family member to examine the blood types of the participants. RESULTS: The serological test results showed a discrepancy between the forward and reverse typings of the female subject. The forward typing was similar to that of AB subtype serological forward typing, while the reverse typing indicated AB blood type. Based on the sequencing results, it is inferred that the female subject and her son have 8 mutations on one BA.02 chain: 297A>G, 526C>G, 657C>T, 700C>G, 703G>A, 796C>A, 803G>C, and 930G>A. Comparing these eight mutation sites with the Blood Group Antigen Gene Mutation Database (BGMUT), it was found that the female subject had a heterozygous mutation at c.700C>G in the 7th exon of the B.01 gene, consistent with the characteristics of the BA.02 allele. The genotype of the female subject was determined as A1.02/ BA.02, while the genotype of her son was determined as O.01.01/BA.02. CONCLUSIONS: The serological presentation of the B(A) subtype for the female subject reported in this study was unique. It differed from previously reported cases, indicating that the determination of B(A) subtypes cannot solely rely on serological testing. It requires a comprehensive analysis combining the results of genetic testing and pedigree investigation.


Assuntos
Sistema ABO de Grupos Sanguíneos , Transfusão de Sangue , Humanos , Feminino , Sistema ABO de Grupos Sanguíneos/genética , Genótipo , Heterozigoto , Mutação , Alelos , Fenótipo
11.
Curr Microbiol ; 81(4): 99, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372800

RESUMO

A novel Gram-stain-positive, oval-shaped, and non-flagellated bacterial strain YIM S02556T was isolated from forest soil in Xiongbi Town, Shizong County, Qujing City, Yunnan Province, southwestern China. The strain exhibited high pairwise 16 S rRNA gene sequence similarity with Psychromicrobium lacuslunae (97.3%) and Psychromicrobium silvestre (96.3%). Strain YIM S02556T exhibited an average nucleotide identity (ANI) of 72.5% with P. lacuslunae IHBB 11,108T and 72.8% ANI with P. silvestre AK 20-18T. The digital DNA-DNA hybridization (dDDH) value between strain YIM S02556T and P. lacuslunae IHBB 11,108T was 20.2%, while with P. silvestre AK 20-18T, the dDDH value was 20.8%. Strain YIM S02556T exhibited optimal growth at 28 °C, pH 7.0, without NaCl. Growth occurred within 10-37 ℃, pH 5.0-8.0, and in the presence of up to 5% w/v NaCl concentration. The genome size was 3.1 Mbp with 64.2% G + C content. The predominant menaquinone was MK-8(H4). The major cellular fatty acid was anteiso-C15:0. Based on the polyphasic analysis, strain YIM S02556T (= KCTC 49,805T = CCTCC AB2020166T) represents a novel Psychromicrobium species in which the name Psychromicrobium xiongbiense sp.nov. was proposed.


Assuntos
Florestas , Cloreto de Sódio , China , Solo , DNA
12.
Eur Spine J ; 33(6): 2322-2331, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38676728

RESUMO

PURPOSE: This study aimed to investigate the association between unilateral high-riding vertebral artery (HRVA) and morphological changes in the atlantoaxial joint (AAJ) and to determine whether unilateral HRVA is a risk factor for atlantoaxial osteoarthritis (AAOA). METHODS: We conducted a retrospective analysis of 2496 patients admitted to our medical center between January 2020 and December 2022 who underwent CT imaging of the cervical spine. Two hundred and seventy-two patients with unilateral HRVA (HRVA group) were identified and a respective 2:1 age- and sex-matched control group without HRVA was built. Morphological parameters, including C2 lateral mass settlement (C2 LMS), C1/2 coronal inclination (C1/2 CI), lateral atlanto-dental interval (LADI), and C1/2 relative rotation angle (C1/2 RRA) were measured. The degree of AAOA was recorded. Risk factors associated with AAOA were identified using univariate and multivariable logistic regression analyses. RESULTS: The study included 61.4% women, and the overall average age of the study population was 48.7 years. The morphological parameters (C2 LMS, C1/2 CI, and LADI) in AAJ were asymmetric between the HRVA and the non-HRVA sides in the HRVA group (p < 0.001). These differences in parameters (d-C2 LMS, d-C1/2 CI, and d-LADI) between the HRVA and the non-HRVA sides, and C1/2 RRA were significantly larger than those in the control group. Eighty-three of 816 patients (10.2%) with AAOA had larger values of d-C2 LMS, d-C1/2 CI, d-LADI, and C1/2 RRA compared with the patients without AAOA (p < 0.05). The multivariable logistic regression analysis indicated that unilateral HRVA [adjusted odds ratio (OR) = 2.6, 95% CI: 1.1-6.3, p = 0.029], age in the sixth decade or older (adjusted OR = 30.2, 95% CI: 16.1-56.9, p < 0.001), women (adjusted OR = 2.1, 95% CI: 1.0-5.6, P = 0.034) were independent risk factors for AAOA. CONCLUSION: Unilateral HRVA was associated with asymmetric morphological changes of nonuniform settlement of C2 lateral mass, lateral slip of atlas, and atlantoaxial rotation displacement. Besides age ≥ 60 years and females, unilateral HRVA is an independent risk factor for AAOA.


Assuntos
Articulação Atlantoaxial , Artéria Vertebral , Humanos , Articulação Atlantoaxial/diagnóstico por imagem , Articulação Atlantoaxial/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/patologia , Estudos Retrospectivos , Adulto , Idoso , Tomografia Computadorizada por Raios X , Osteoartrite/diagnóstico por imagem , Osteoartrite/patologia , Osteoartrite/epidemiologia , Vértebras Cervicais/diagnóstico por imagem , Osteoartrite da Coluna Vertebral/diagnóstico por imagem , Osteoartrite da Coluna Vertebral/epidemiologia , Osteoartrite da Coluna Vertebral/patologia
13.
BMC Nurs ; 23(1): 244, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627801

RESUMO

BACKGROUND: On December 7, 2022, the Joint Prevention and Control Mechanism of China's State Council released the "Ten New Guidelines" to optimize the coronavirus disease 2019 (COVID-19) prevention policies further. This signaled a broader shift from "dynamic clearing" to "coexisting with the virus" nationwide. OBJECTIVE: This study aims to examine the experiences and perspectives of interdisciplinary nurses during the COVID-19 outbreak in China after the implementation of the "Ten New Guidelines". The goal is to understand the challenges faced by this unique nursing group and inform organizational support to bolster their well-being and resilience. METHODS: Two tertiary hospitals in southeastern Zhejiang Province were selected, with interdisciplinary nurses chosen as subjects. A constructivist qualitative research approach was employed, using semi-structured face-to-face interviews. Research data were collected through interviews and analyzed using content analysis. RESULTS: Fifteen interdisciplinary nurses were included in this study. The analysis revealed four main themes and nine sub-themes. The main themes were: (1) ineffective organizational support (inadequate organizational care, poor PPE, excessive workload), (2) physiological distress after contracting COVID-19 (extreme physical fatigue, leakage of urine due to severe coughing), (3) fear of being wrong (fear of being reprimanded in public, psychological anxiety), and (4) family responsibility anxiety (difficulty of loyalty and filial piety, obligations to their children). CONCLUSION: We provide new evidence that organizations must proactively address the support, training, and communication needs of staff, particularly interdisciplinary nurses, to supplement epidemic containment. This is also essential in helping mitigate the work-family conflicts such roles can create.

14.
J Am Chem Soc ; 145(21): 11745-11753, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37204420

RESUMO

Herein, we report a highly efficient synthesis of enantioenriched aza-[3.3.1]-bicyclic enamines and ketones, a class of structural cores in many natural products, via asymmetric dearomatization of indoles with azodicarboxylates. The reaction is initiated by electrophilic amination and followed by aza-Prins cyclization/phenonium-like rearrangement. A newly developed fluorine-containing chiral phosphoric acid displays excellent activity in promoting this cascade reaction. The absence or presence of water as the additive directs the reaction pathway toward either enamine or ketone products in high yields (up to 93%) with high enantiopurity (up to 98% ee). Comprehensive density functional theory (DFT) calculations reveal the energy profile of the reaction and the origins of enantioselectivity and water-induced chemoselectivity.

15.
J Am Chem Soc ; 145(36): 19523-19532, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37646485

RESUMO

Structural transformation of metal nanoclusters (NCs) is of great ongoing interest regarding their synthesis, stability, and reactivity. Although sporadic examples of cluster transformations have been reported, neither the underlying transformation mechanism nor the intermediates are unambiguous. Herein, we have synthesized a flexible 54-nuclei silver cluster (Ag54) by combining soft (tBuC≡C-) and hard (nPrCOO-) ligands. The existence of weakly coordinated nPrCOO- enhances the reactivity of Ag54, thus facilitating the dicarboxylic acid to induce structural transformation. X-ray structural analyses reveal that Ag54 transforms to Ag28 cluster-based 2D networks (Ag28a and Ag28b) induced by H2suc (succinic acid) and H2glu (glutaric acid), whereas with H2pda (2,2'-(1,2-phenylene)diacetic acid), a discrete Ag28 cluster (Ag28c) is isolated. The key intermediate Ag17 that emerges during the self-dissociation of Ag54 was isolated by using cryogenic recrystallization and characterized by X-ray crystallography. The "tandem transformation" mechanism for the structure evolution from Ag54 to Ag28a is established by time-dependent electrospray ionization mass spectrometry (ESI-MS) and UV-vis spectroscopy. In addition, the catalytic activity in the 4-nitrophenol reduction follows the sequence Ag28c > Ag28b > Ag28a > Ag54 due to more bare silver sites on the surface of the Ag28 cluster unit. Our findings not only open new avenues to the synthesis of silver NCs but also shed light on a better understanding of the structural transformation mechanism from one cluster to another or cluster-based metal-organic networks induced by dicarboxylates.

16.
Anal Chem ; 95(40): 14934-14943, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37752733

RESUMO

Methods to manipulate magnetic beads are essential factors to determine the efficiency and dimension of an in vitro diagnostic system. Currently, using movable permanent magnets and planar electromagnets is still the major approach to achieve magnetic bead control, causing significant constraint in the miniaturization of in vitro diagnostic systems. Here, we propose techniques to construct a fully integrated microfluidic device that can conduct automatic magnetic bead manipulation as well as rapid chemical reaction and cleaning in a minimized dimension similar to a USB disk. The device combines the precision control of multiple electromagnetic coils with the compactness of microfluidic channels, leading to one of the smallest automatic magnetic bead manipulation systems that can complete several major magnetic bead-based operation steps such as sample injection, reaction, cleaning, and collection. The influencing factors such as coil driving parameters, surface treatment of the microchannels, and properties of magnetic particles have also been investigated to optimize the device performance. The device can drive mixtures of Fe3O4 microparticles and polymer magnetic beads (PMBs) with a weight ratio of 1:1 at a maximum speed of 0.5 cm·s-1 and reduce the time for DNA binding and dissociation reactions from 20 min to only 48 s. This device has significantly advanced the conventional manipulation methods of magnetic beads and has demonstrated the possibility to construct an automatic and ultraminiaturized in vitro diagnostic system that may facilitate portable or even wearable chemical analysis.

17.
Small ; 19(39): e2302241, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37260144

RESUMO

Precisely delivering light to multiple locations in biological tissue is crucial for advancing multiregional optogenetics in neuroscience research. However, conventional implantable devices typically have rigid geometries and limited light sources, allowing only single or dual probe placement with fixed spacing. Here, a fully flexible optogenetic device with multiple thin-film microscale light-emitting diode (µ-LED) displays scattering from a central controller is presented. Each display is heterogeneously integrated with thin-film 5 × 10 µ-LEDs and five optical fibers 125 µm in diameter to achieve cellular-scale spatial resolution. Meanwhile, the device boasts a compact, flexible circuit capable of multichannel configuration and wireless transmission, with an overall weight of 1.31 g, enabling wireless, real-time neuromodulation of freely moving rats. Characterization results and finite element analysis have demonstrated excellent optical properties and mechanical stability, while cytotoxicity tests further ensure the biocompatibility of the device for implantable applications. Behavior studies under optogenetic modulation indicate great promise for wirelessly modulating neural functions in freely moving animals. The device with multisite and multiregional optogenetic modulation capability offers a comprehensive platform to advance both fundamental neuroscience studies and potential applications in brain-computer interfaces.


Assuntos
Optogenética , Próteses e Implantes , Ratos , Animais , Optogenética/métodos , Fibras Ópticas , Tecnologia sem Fio , Córtex Cerebral
18.
Chemistry ; 29(70): e202302773, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-37750566

RESUMO

Lithium (Li) metal is a promising anode candidate for high-energy-density batteries owing to its high theoretical capacity and low electrochemical potential. However, uneven Li nucleation, uncontrollable dendritic growth, infinite voltage change and even safety issues hinder its commercial application. Herein, a three-dimensional (3D) framework of freestanding vanadium nitride nanowires (VN NWs) is established as Li host for dendrite-free Li metal anode. A lithiophilic Li3 N interlayer which in situ formed by the surface reaction between molten Li and VN NWs is utilized to guide a uniform Li nucleation and deposition within the skeleton, as well as avoid the dendrite formation. Meanwhile, VN NWs can decrease local current density, homogenize Li-ion flux and accommodate volume fluctuations of the anode due to its 3D structure with high electron conductivity. Thus, the corresponding composite Li metal anode delivers a long-life span of 500 cycles (1000 h) at a current density of 0.5 mA cm-2 , and exhibits lower nucleation over-potential and voltage hysteresis at different current densities from 0.5~5 mA cm-2 in carbonate electrolyte. In conclusion, this work provides a new type of scaffold with both high electronic conductivity and excellent lithiophilicity for stable Li anodes.

19.
J Org Chem ; 88(5): 2898-2907, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36802599

RESUMO

An efficient triflic anhydride promoted phosphorylation of ketone was disclosed, and vinylphosphorus compounds were prepared under solvent- and metal-free conditions. Both aryl and alkyl ketones could perform smoothly to give vinyl phosphonates in high to excellent yields. In addition, the reaction was easy to carry out and easy to scale up. Mechanistic studies suggested that this transformation might involve nucleophilic vinylic substitution or a nucleophilic addition-elimination mechanism.

20.
Bioorg Med Chem ; 82: 117234, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36906964

RESUMO

Cancer with low survival rates is the second main cause of death among all diseases in the world and consequently, effective antineoplastic agents are urgently needed. Allosecurinine is a plant-derived indolicidine securinega alkaloid shown bioactivity. The object of this study is to investigate synthetic allosecurinine derivatives with considerable anticancer capacity against nine human cancer cell lines as well as mechanism of action. We synthesized twenty-three novel allosecurinine derivatives and evaluated their antitumor activity against nine cancer cell lines for 72 h by MTT and CCK8 assays. FCM was applied to analyze the apoptosis, mitochondrial membrane potential, DNA content, ROS production, CD11b expression. Western blot was selected to analyze the protein expression. Structure-activity relationships were established and potential anticancer lead BA-3 which induced differentiation of leukemia cells towards granulocytosis at low concentration and apoptosis at high concentration was identified. Mechanism studies showed that mitochondrial pathway mediated apoptosis within cancer cells with cell cycle blocking was induced by BA-3. In addition, western blot assays revealed that BA-3 induced expression of the proapoptotic factor Bax, p21 and reduced the levels of antiapoptotic protein such as Bcl-2, XIAP, YAP1, PARP, STAT3, p-STAT3, and c-Myc. Collectively, BA-3 was a lead compound for oncotherapy at least in part, through the STAT3 pathway. These results were an important step in further studies on allosecurinine-based antitumor agent development.


Assuntos
Alcaloides , Antineoplásicos , Compostos Heterocíclicos de Anel em Ponte , Neoplasias , Humanos , Antineoplásicos/farmacologia , Azepinas/farmacologia , Compostos Heterocíclicos de Anel em Ponte/farmacologia , Lactonas/farmacologia , Apoptose , Alcaloides/farmacologia , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral
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