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1.
Drug Resist Updat ; 73: 101059, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38295753

RESUMO

Patients with bladder cancer (BCa) frequently acquires resistance to platinum-based chemotherapy, particularly cisplatin. This study centered on the mechanism of cisplatin resistance in BCa and highlighted the pivotal role of lactylation in driving this phenomenon. Utilizing single-cell RNA sequencing, we delineated the single-cell landscape of Bca, pinpointing a distinctive subset of BCa cells that exhibit marked resistance to cisplatin with association with glycolysis metabolism. Notably, we observed that H3 lysine 18 lactylation (H3K18la) plays a crucial role in activating the transcription of target genes by enriching in their promoter regions. Targeted inhibition of H3K18la effectively restored cisplatin sensitivity in these cisplatin-resistant epithelial cells. Furthermore, H3K18la-driven key transcription factors YBX1 and YY1 promote cisplatin resistance in BCa. These findings enhance our understanding of the mechanisms underlying cisplatin resistance, offering valuable insights for identifying novel intervention targets to overcome drug resistance in Bca.


Assuntos
Cisplatino , Neoplasias da Bexiga Urinária , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Histonas/genética , Histonas/metabolismo , Análise da Expressão Gênica de Célula Única , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo
2.
J Hum Genet ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866925

RESUMO

BACKGROUND: Intronic GAA repeat expansion ([GAA] ≥250) in FGF14 is associated with the late-onset neurodegenerative disorder, spinocerebellar ataxia 27B (SCA27B, GAA-FGF14 ataxia). We aim to determine the prevalence of the GAA repeat expansion in FGF14 in Chinese populations presenting late-onset cerebellar ataxia (LOCA) and evaluate the characteristics of tandem repeat inheritance, radiological features and sympathetic nerve involvement. METHODS: GAA-FGF14 repeat expansion was screened in an undiagnosed LOCA cohort (n = 664) and variations in repeat-length were analyzed in families of confirmed GAA-FGF14 ataxia patients. Brain magnetic resonance imaging (MRI) was used to evaluate the radiological feature in GAA-FGF14 ataxia patients. Clinical examinations and sympathetic skin response (SSR) recordings in GAA-FGF14 patients (n = 16) were used to quantify sympathetic nerve involvement. RESULTS: Two unrelated probands (2/664) were identified. Genetic screening for GAA-FGF14 repeat expansion was performed in 39 family members, 16 of whom were genetically diagnosed with GAA-FGF14 ataxia. Familial screening revealed expansion of GAA repeats in maternal transmissions, but contraction upon paternal transmission. Brain MRI showed slight to moderate cerebellar atrophy. SSR amplitude was lower in GAA-FGF14 patients in pre-symptomatic stage compared to healthy controls, and further decreased in the symptomatic stage. CONCLUSIONS: GAA-FGF14 ataxia was rare among Chinese LOCA cases. Parental gender appears to affect variability in GAA repeat number between generations. Reduced SSR amplitude is a prominent feature in GAA-FGF14 patients, even in the pre-symptomatic stage.

3.
Ann Neurol ; 93(2): 244-256, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36088542

RESUMO

OBJECTIVE: Despite the increasing number of genes associated with Charcot-Marie-Tooth (CMT) disease, many patients currently still lack appropriate genetic diagnosis for this disease. Autosomal dominant mutations in aminoacyl-tRNA synthetases (ARSs) have been implicated in CMT. Here, we describe causal missense mutations in the gene encoding seryl-tRNA synthetase 1 (SerRS) for 3 families affected with CMT. METHODS: Whole-exome sequencing was performed in 16 patients and 14 unaffected members of 3 unrelated families. The functional impact of the genetic variants identified was investigated using bioinformatic prediction tools and confirmed using cellular and biochemical assays. RESULTS: Combined linkage analysis for the 3 families revealed significant linkage (Zmax LOD = 6.9) between the genomic co-ordinates on chromosome 1: 108681600-110300504. Within the linkage region, heterozygous SerRS missense variants segregated with the clinical phenotype in the 3 families. The mutant SerRS proteins exhibited reduced aminoacylation activity and abnormal SerRS dimerization, which suggests the impairment of total protein synthesis and induction of eIF2α phosphorylation. INTERPRETATION: Our findings suggest the heterozygous SerRS variants identified represent a novel cause for autosomal dominant CMT. Mutant SerRS proteins are known to impact various molecular and cellular functions. Our findings provide significant advances on the current understanding of the molecular mechanisms associated with ARS-related CMT. ANN NEUROL 2023;93:244-256.


Assuntos
Doença de Charcot-Marie-Tooth , Serina-tRNA Ligase , Humanos , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/metabolismo , Serina-tRNA Ligase/genética , Mutação , Heterozigoto , Mutação de Sentido Incorreto/genética
4.
Opt Lett ; 49(1): 109-112, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134164

RESUMO

Photoinhibition (PI) mechanisms have been introduced in nanofabrication which allows breaking the diffraction limit by large factors. Donut-shaped laser is usually selected as a depletion beam to reduce linewidth, but the parasitic process has made the results of the experiment less than expected. As a result, the linewidth is difficult to achieve below 50 nm with 780 nm femtosecond and 532 nm continuous-wave lasers. Here, we propose a new, to the best of our knowledge, method based on a center-non-zero (CNZ) depletion laser to further reduce linewidth. By constructing a smaller zone of action under the condition of keeping the maximum depletion intensity constant, a minimum linewidth of 30 nm (λ / 26) was achieved. Two ways to construct CNZ spots were discussed and experimented, and the results show the advantages of our method to reduce the parasitic process to further improve the writing resolution.

5.
Langmuir ; 40(13): 6786-6805, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38503426

RESUMO

Traditional heterogeneous catalysts are affected in the catalytic hydrogenation of PS by the scale effect, viscosity effect, adhesion effect, and conformational effect, resulting in poor activity and stability. Monolithic Pd-CNTs@FN catalysts could eliminate or weaken the impact of these negative effects. We grew nitrogen-doped carbon nanotubes (NCNTs) on monolithic-foamed nickel (FN) and investigate their growth mechanism. Meanwhile, the feasibility of using the NCNTs@FN carrier for PS hydrogenation reaction was also verified. The growth of NCNTs on FN can be divided into 3 stages: initial growth stage, stable growth stage, and supersaturation stage. Finally, a three-layer structure of NCNT layer, dense carbon layer, and FN skeleton is formed. Two types of structures, nickel-doped carbon nanotubes (NiCNTs) and C-Ni alloy, are formed by combining C and Ni, while four nitrogen-doped structures, NPD, NPR, NG, and NO, are formed by C and N. The prepared carrier exhibited an extremely outstanding specific surface area (2.829 × 106 cm2/g) and strength (no NCNTs falling off after 24 h 500 rpm agitation), as well as high catalytic activity for PS hydrogenation after loaded with Pd (2.13 ± 0.95 nm), with a TOF of up to 27.6 gPS/(gPd•h). After 8 repetitions of the catalyst, there was no significant decrease in activity. This proves the excellent performance of Pd-NCNTs@FN in polymer hydrogenation reactions, laying a solid foundation for further research on the mechanism of NCNTs promoting PS hydrogenation and regulating the growth of NCNTs.

6.
J Nat Prod ; 87(1): 28-37, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38204395

RESUMO

Fengycin has great potential for applications in biological control because of its biosafety and degradability. In this study, the addition of exogenous precursors increased fengycin production by Bacillus subtilis. Corynebacterium glutamicum was engineered to produce high levels of precursors (Thr, Pro, Val, and Ile) to promote the biosynthesis of fengycin. Furthermore, recombinant C. glutamicum and Yarrowia lipolytica providing amino acid and fatty acid precursors were co-cultured to improve fengycin production by B. subtilis in a three-strain artificial consortium, in which fengycin production was 2100 mg·L-1. In addition, fengycin production by the consortium in a 5 L bioreactor reached 3290 mg·L-1. Fengycin had a significant antifungal effect on Rhizoctonia solani, which illustrates its potential as a food preservative. Taken together, this work provides a new strategy for improving fengycin production by a microbial consortium and metabolic engineering.


Assuntos
Bacillus subtilis , Consórcios Microbianos , Bacillus subtilis/química , Lipopeptídeos/química , Antifúngicos/química
7.
Lipids Health Dis ; 23(1): 180, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862993

RESUMO

BACKGROUND: The management of male infertility continues to encounter an array of challenges and constraints, necessitating an in-depth exploration of novel therapeutic targets to enhance its efficacy. As an eight-carbon medium-chain fatty acid, octanoic acid (OCA) shows promise for improving health, yet its impact on spermatogenesis remains inadequately researched. METHODS: Mass spectrometry was performed to determine the fatty acid content and screen for a pivotal lipid component in the serum of patients with severe spermatogenesis disorders. The sperm quality was examined, and histopathological analysis and biotin tracer tests were performed to assess spermatogenesis function and the integrity of the blood-testis barrier (BTB) in vivo. Cell-based in vitro experiments were carried out to investigate the effects of OCA administration on Sertoli cell dysfunction. This research aimed to elucidate the mechanism by which OCA may influence the function of Sertoli cells. RESULTS: A pronounced reduction in OCA content was observed in the serum of patients with severe spermatogenesis disorders, indicating that OCA deficiency is related to spermatogenic disorders. The protective effect of OCA on reproduction was tested in a mouse model of spermatogenic disorder induced by busulfan at a dose 30 mg/kg body weight (BW). The mice in the study were separated into distinct groups and administered varying amounts of OCA, specifically at doses of 32, 64, 128, and 256 mg/kg BW. After evaluating sperm parameters, the most effective dose was determined to be 32 mg/kg BW. In vivo experiments showed that treatment with OCA significantly improved sperm quality, testicular histopathology and BTB integrity, which were damaged by busulfan. Moreover, OCA intervention reduced busulfan-induced oxidative stress and autophagy in mouse testes. In vitro, OCA pretreatment (100 µM) significantly ameliorated Sertoli cell dysfunction by alleviating busulfan (800 µM)-induced oxidative stress and autophagy. Moreover, rapamycin (5 µM)-induced autophagy led to Sertoli cell barrier dysfunction, while OCA administration exerted a protective effect by alleviating autophagy. CONCLUSIONS: This study demonstrated that OCA administration suppressed oxidative stress and autophagy to alleviate busulfan-induced BTB damage. These findings provide a deeper understanding of the toxicology of busulfan and a promising avenue for the development of novel OCA-based therapies for male infertility.


Assuntos
Autofagia , Barreira Hematotesticular , Bussulfano , Caprilatos , Estresse Oxidativo , Células de Sertoli , Espermatogênese , Masculino , Animais , Barreira Hematotesticular/efeitos dos fármacos , Barreira Hematotesticular/metabolismo , Bussulfano/efeitos adversos , Caprilatos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Camundongos , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Humanos , Espermatogênese/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Infertilidade Masculina/tratamento farmacológico , Infertilidade Masculina/induzido quimicamente , Infertilidade Masculina/patologia , Testículo/efeitos dos fármacos , Testículo/patologia , Testículo/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Adulto
8.
J Ultrasound Med ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808580

RESUMO

OBJECTIVE: This study seeks to construct a machine learning model that merges clinical characteristics with ultrasound radiomic analysis-encompassing both the intratumoral and peritumoral-to predict the status of axillary lymph nodes in patients with early-stage breast cancer. METHODS: The study employed retrospective methods, collecting clinical information, ultrasound data, and postoperative pathological results from 321 breast cancer patients (including 224 in the training group and 97 in the validation group). Through correlation analysis, univariate analysis, and Lasso regression analysis, independent risk factors related to axillary lymph node metastasis in breast cancer were identified from conventional ultrasound and immunohistochemical indicators, and a clinical feature model was constructed. Additionally, features were extracted from ultrasound images of the intratumoral and its 1-5 mm peritumoral to establish a radiomics feature formula. Furthermore, by combining clinical features and ultrasound radiomics features, six machine learning models (Logistic Regression, Decision Tree, Support Vector Machine, Extreme Gradient Boosting, Random Forest, and K-Nearest Neighbors) were compared for diagnostic efficacy, and constructing a joint prediction model based on the optimal ML algorithm. The use of Shapley Additive Explanations (SHAP) enhanced the visualization and interpretability of the model during the diagnostic process. RESULTS: Among the 321 breast cancer patients, 121 had axillary lymph node metastasis, and 200 did not. The clinical feature model had an AUC of 0.779 and 0.777 in the training and validation groups, respectively. Radiomics model analysis showed that the model including the Intratumor +3 mm peritumor area had the best diagnostic performance, with AUCs of 0.847 and 0.844 in the training and validation groups, respectively. The joint prediction model based on the XGBoost algorithm reached AUCs of 0.917 and 0.905 in the training and validation groups, respectively. SHAP analysis indicated that the Rad Score had the highest weight in the prediction model, playing a significant role in predicting axillary lymph node metastasis in breast cancer. CONCLUSION: The predictive model, which integrates clinical features and radiomic characteristics using the XGBoost algorithm, demonstrates significant diagnostic value for axillary lymph node metastasis in breast cancer. This model can provide significant references for preoperative surgical strategy selection and prognosis evaluation for breast cancer patients, helping to reduce postoperative complications and improve long-term survival rates. Additionally, the utilization of SHAP enhancing the global and local interpretability of the model.

9.
Ecotoxicol Environ Saf ; 281: 116667, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964068

RESUMO

Elucidating the absorption and translocation of heavy metal(loid)s by common vegetables across different growth environments and stages is crucial for conducting accurate environmental risk assessments and for associated control. This study investigated temporal variations in the absorption and translocation capacities of pak choi (Brassica rapa L.) for As, Cd, Cr, Cu, Pb, and Zn in polluted soils during the plant growth cycle under greenhouse and open-field cultivation modes. Results showed high root metal(loid) bioconcentration factors and root-to-shoot translocation factors for Cd (0.25 and 1.44, respectively) and Zn (0.26 and 1.01), but low values for As (0.06 and 0.88) and Pb (0.06 and 0.87). The Cd concentration in the aerial edible parts peaked during the early slow growth period, whereas other heavy metal(loid)s peaked during the later stable maturity period. Root bioconcentration and root-to-shoot translocation factors did not significantly differ between cultivation modes. However, greenhouse cultivation exhibited lower average Cd and Zn concentrations in the edible parts and cumulative uptake amounts of most metal(loid)s than open-field cultivation during the typical harvest period spanning days 60 and 90. Short-term transitioning from open-field to greenhouse cultivation may reduce health risks associated with heavy metal(loid) intake via pak choi consumption. These findings facilitate sustainable agricultural practices and food safety management.

10.
J Clin Ultrasound ; 52(3): 274-283, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38105371

RESUMO

BACKGROUND: Explore the feasibility of using the multimodal ultrasound (US) radiomics technology to diagnose American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) 4-5 thyroid nodules. METHOD: This study prospectively collected the clinical characteristics, conventional, and US elastography images of 100 patients diagnosed with ACR TI-RADS 4-5 nodules from May 2022 to 2023. Independent risk factors for malignant thyroid nodules were extracted and screened using methods such as the least absolute shrinkage and selection operator (LASSO) logistic regression (LR) model, and a multimodal US radiomics combined diagnostic model was established. Using a multifactorial LR analysis and a Rad-score rating, the predictive performance was validated and evaluated, and the final threshold range was determined to assess the clinical net benefit of the model. RESULTS: In the training set, the US radiomics combined predictive model area under curve (AUC = 0.928) had higher diagnostic performance compared with clinical characteristics (AUC = 0.779), conventional US (AUC = 0.794), and US elastography model (AUC = 0.852). In the validation set, the multimodal US radiomics combined diagnostic model (AUC = 0.829) also had higher diagnostic performance compared with clinical characteristics (AUC = 0.799), conventional US (AUC = 0.802), and US elastography model (AUC = 0.718). CONCLUSION: Multi-modal US radiomics technology can effectively diagnose thyroid nodules of ACR TI-RADS 4-5, and the combination of radiomics signature and conventional US features can further improve the diagnostic performance.


Assuntos
Técnicas de Imagem por Elasticidade , Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Radiômica , Estudos Retrospectivos , Ultrassonografia/métodos , Tecnologia
11.
Ann Neurol ; 92(3): 512-526, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35700120

RESUMO

OBJECTIVE: Oculopharyngodistal myopathy (OPDM) is an adult-onset neuromuscular disease characterized by progressive ptosis, dysarthria, ophthalmoplegia, and distal muscle weakness. Recent studies revealed that GGC repeat expansions in 5'-UTR of LRP12, GIPC1, and NOTCH2NLC are associated with OPDM. Despite these advances, approximately 30% of OPDM patients remain genetically undiagnosed. Herein, we aim to investigate the genetic basis for undiagnosed OPDM patients in two unrelated Chinese Han families. METHODS: Parametric linkage analysis was performed. Long-read sequencing followed by repeat-primed polymerase chain reaction and amplicon length polymerase chain reaction were used to determine the genetic cause. Targeted methylation sequencing was implemented to detect epigenetic changes. The possible pathogenesis mechanism was investigated by quantitative polymerase chain reaction, immunoblotting, RNA fluorescence in situ hybridization, and immunofluorescence staining of muscle biopsy samples. RESULTS: The disease locus was mapped to 12q24.3. Subsequently, GGC repeat expansion in the promoter region of RILPL1 was identified in six OPDM patients from two families, findings consistent with a founder effect, designated as OPDM type 4. Targeted methylation sequencing revealed hypermethylation at the RILPL1 locus in unaffected individuals with ultralong expansion. Analysis of muscle samples showed no significant differences in RILPL1 mRNA or RILPL1 protein levels between patients and controls. Public CAGE-seq data indicated that alternative transcription start sites exist upstream of the RefSeq-annotated RILPL1 transcription start site. Strand-specific RNA-seq data revealed bidirectional transcription from the RILPL1 locus. Finally, fluorescence in situ hybridization/immunofluorescence staining showed that both sense and antisense transcripts formed RNA foci, and were co-localized with hnRNPA2B1 and p62 in the intranuclear inclusions of OPDM type 4 patients. INTERPRETATION: Our findings implicate abnormal GGC repeat expansions in the promoter region of RILPL1 as a novel genetic cause for OPDM, and suggest a methylation mechanism and a potential RNA toxicity mechanism are involved in OPDM type 4 pathogenesis. ANN NEUROL 2022;92:512-526.


Assuntos
Distrofias Musculares , Adulto , Humanos , Hibridização in Situ Fluorescente , Corpos de Inclusão Intranuclear/patologia , Distrofias Musculares/genética , Linhagem , RNA , Expansão das Repetições de Trinucleotídeos/genética
12.
Blood ; 137(21): 2920-2934, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-33512466

RESUMO

OBF1 is a specific coactivator of the POU family transcription factors OCT1 and OCT2. OBF1 and OCT2 are B cell-specific and indispensable for germinal center (GC) formation, but their mechanism of action is unclear. Here, we show by chromatin immunoprecipitation-sequencing that OBF1 extensively colocalizes with OCT1 and OCT2. We found that these factors also often colocalize with transcription factors of the ETS family. Furthermore, we showed that OBF1, OCT2, and OCT1 bind widely to the promoters or enhancers of genes involved in GC formation in mouse and human GC B cells. Short hairpin RNA knockdown experiments demonstrated that OCT1, OCT2, and OBF1 regulate each other and are essential for proliferation of GC-derived lymphoma cell lines. OBF1 downregulation disrupts the GC transcriptional program: genes involved in GC maintenance, such as BCL6, are downregulated, whereas genes related to exit from the GC program, such as IRF4, are upregulated. Ectopic expression of BCL6 does not restore the proliferation of GC-derived lymphoma cells depleted of OBF1 unless IRF4 is also depleted, indicating that OBF1 controls an essential regulatory node in GC differentiation.


Assuntos
Centro Germinativo/metabolismo , Fator 1 de Transcrição de Octâmero/fisiologia , Fator 2 de Transcrição de Octâmero/uso terapêutico , Transativadores/uso terapêutico , Transcrição Gênica/genética , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Ontologia Genética , Células HEK293 , Humanos , Lipopolissacarídeos/farmacologia , Linfoma não Hodgkin/genética , Linfoma não Hodgkin/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fator 1 de Transcrição de Octâmero/deficiência , Fator 1 de Transcrição de Octâmero/genética , Fator 2 de Transcrição de Octâmero/deficiência , Fator 2 de Transcrição de Octâmero/genética , Proteína Proto-Oncogênica c-ets-1/análise , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas Recombinantes/metabolismo , Transativadores/deficiência , Transativadores/genética
13.
BMC Cancer ; 23(1): 1220, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082377

RESUMO

OBJECTIVE: The aim of this study is to evaluate an AAV vector that can selectively target breast cancer cells and to investigate its specificity and anti-tumor effects on breast cancer cells both in vitro and in vivo, offering a new therapeutic approach for the treatment of EpCAM-positive breast cancer. METHODS: In this study, a modified AAV2 viral vector was used, in which EpCAM-specific DARPin EC1 was fused to the VP2 protein of AAV2, creating a viral vector that can target breast cancer cells. The targeting ability and anti-tumor effects of this viral vector were evaluated through in vitro and in vivo experiments. RESULTS: The experimental results showed that the AAV2MEC1 virus could specifically infect EpCAM-positive breast cancer cells and accurately deliver the suicide gene HSV-TK to tumor tissue in mice, significantly inhibiting tumor growth. Compared to the traditional AAV2 viral vector, the AAV2MEC1 virus exhibited reduced accumulation in liver tissue and had no impact on tumor growth. CONCLUSION: This study demonstrates that AAV2MEC1 is a gene delivery vector capable of targeting breast cancer cells and achieving selective targeting in mice. The findings offer a potential gene delivery system and strategies for gene therapy targeting EpCAM-positive breast cancer and other tumor types.


Assuntos
Neoplasias da Mama , Proteínas de Repetição de Anquirina Projetadas , Humanos , Camundongos , Animais , Feminino , Molécula de Adesão da Célula Epitelial/genética , Molécula de Adesão da Célula Epitelial/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Neoplasias da Mama/patologia , Técnicas de Transferência de Genes , Terapia Genética/métodos , Vetores Genéticos/genética , Dependovirus/genética , Dependovirus/metabolismo
14.
High Educ (Dordr) ; : 1-23, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37362755

RESUMO

WeChat is a highly popular social media in China and many other Asian countries, but little is known about its effectiveness in facilitating international students' academic and social functioning. Hence, the present study aimed to examine causal or reciprocal relationships among WeChat usage intensity, behavioral engagement in academic learning (BE-academic) and in local social activities (BE-social), and academic and social adjustment. To this end, we employed a three-wave longitudinal design among international students in China with data collected at three times (i.e., Time 1 data collected in December of 2020, Time 2 data collected in March of 2021, and Time 3 data collected in June of 2021). Results based on the cross-lagged panel analyses indicated that in academic domains, WeChat usage intensity positively predicted longitudinal changes in BE-academic and academic adjustment positively predicted longitudinal changes in WeChat usage intensity across Time 1 and Time 3. In social domains, WeChat usage intensity positively predicted longitudinal changes in BE-social and social adjustment, and BE-social positively predicted longitudinal changes in social adjustment from Time 1 to Time 2. Additionally, the reverse effects of social adjustment on WeChat usage intensity were revealed across Time 1 and Time 3.

15.
Angew Chem Int Ed Engl ; 62(32): e202305390, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37261869

RESUMO

Adsorption-based removal of carbon dioxide (CO2 ) from gas mixtures has demonstrated great potential for solving energy security and environmental sustainability challenges. However, due to similar physicochemical properties between CO2 and other gases as well as the co-adsorption behavior, the selectivity of CO2 is severely limited in currently reported CO2 -selective sorbents. To address the challenge, we create a bioinspired design strategy and report a robust, microporous metal-organic framework (MOF) with unprecedented [Mn86 ] nanocages. Attributed to the existence of unique enzyme-like confined pockets, strong coordination interactions and dipole-dipole interactions are generated for CO2 molecules, resulting in only CO2 molecules fitting in the pocket while other gas molecules are prohibited. Thus, this MOF can selectively remove CO2 from various gas mixtures and show record-high selectivities of CO2 /CH4 and CO2 /N2 mixtures. Highly efficient CO2 /C2 H2 , CO2 /CH4 , and CO2 /N2 separations are achieved, as verified by experimental breakthrough tests. This work paves a new avenue for the fabrication of adsorbents with high CO2 selectivity and provides important guidance for designing highly effective adsorbents for gas separation.

16.
Biochem Biophys Res Commun ; 597: 122-127, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35144174

RESUMO

Sustained hypercatabolism induced by sepsis contributed to serious complications and mortality in the intensive care unit. Enteral nutrition (EN) was required to maintain the energy balance during sepsis. Ghrelin, which was stimulated secretion by EN, had been shown to regulate energy homeostasis. Therefore, we tested whether EN alleviated hypercatabolism through ghrelin/GH secretagogue receptor 1α (GHS-R1α)-proopiomelanocortin (POMC) in endotoxemic rats. Rats in the Sham and lipopolysaccharide (LPS) groups were free access to rodent chow diet and water. Rats in the EN, EN + Lys and EN + 3-MA groups were intracerebroventricularly injected with saline, D-Lys3-GHRP-6 or 3-MA and then received EN for three days. Hypercatabolism was measured by the change of body weight, insulin resistance, leptin, corticosterone, muscle protein synthesis and atrophy. Serum and hypothalamic total ghrelin, acylated ghrelin, GHS-R1α and AMP-activated protein kinase (AMPK)-autophagy-POMC pathway were also detected. The results showed that EN increased serum and hypothalamic total ghrelin, acylated ghrelin and GHS-R1α, effectively activated the hypothalamic AMPK-autophagy-POMC pathway and alleviated hypercatabolism in endotoxemic rats. The improving effects of EN on hypercatabolism and hypothalamic AMPK-autophagy-POMC pathway were abolished with the central administration of D-Lys3-GHRP-6 to inhibited hypothalamic GHS-R1α. And with the central administration of 3-MA to inhibited hypothalamic autophagy, the improving effect of EN on hypercatabolism was also abolished in endotoxemic rats. In conclusions, EN could significantly alleviate hypercatabolism through ghrelin/GHS-R1α-POMC in endotoxemic rats.

17.
Small ; 18(47): e2203354, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36180408

RESUMO

The ambient air-processed preparation of kesterite Cu2 ZnSn(S,Se)4 (CZTSSe) thin film is highly promising for the fabrication of low-cost and eco-friendly solar cells. However, the Sn volatilization loss and formation of a thick Mo(S,Se)2 interfacial layer during the traditional selenization process pose challenges for fabricating high-efficiency CZTSSe solar cells. Here, CZTS precursors prepared by a sol-gel process in ambient air are selenized and assisted with SnSe2 vapor via one- and two-step selenization to prepare a CZTSSe absorber on a Mo film and, subsequently, solar cells. For one-step selenization, the thickness of the fine grain and Mo(S,Se)2 layers near the back contact can be significantly reduced with increasing SnSe2 vapor partial pressure in the mixed selenization atmosphere, while the device efficiency is only 7.97% due to the severe interface recombination. For two-step selenization, the desired morphology and stoichiometry of the absorber can be achieved through the assistance of Sn-poor precursors selenized with high SnSe2 vapor partial pressure to regulate the Sn content in CZTSSe, yielding the highest efficiency of 10.85%. This study improves the understanding of the key role of the microenvironment during film growth towards the production of high-efficiency thin film solar cells and other photoelectronic devices.

18.
BMC Cancer ; 22(1): 1238, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36451138

RESUMO

BACKGROUND: There is still uncertainty on whether ionizing radiation from CT scans can increase the risks of cancer. This study aimed to identify the association of cumulative ionizing radiation from CT scans with pertaining cancer risks in adults. METHODS: Five databases were searched from their inception to November 15, 2020. Observational studies reporting cancer risks from CT scans in adults were included. The main outcome included quantified cancer risks as cancer case numbers in exposed/unexposed adult participants with unified converted measures to odds ratio (OR) for relative risk, hazard ratio. Global background radiation (2.4 mSv per year) was used as control for lifetime attribution risk (LAR), with the same period from incubation after exposure until survival to 100 years. RESULTS: 25 studies were included with a sum of 111,649,943 participants (mean age: 45.37 years, 83.4% women), comprising 2,049,943 actual participants from 6 studies with an average follow-up period as 30.1 years (range, 5 to 80 years); 109,600,000 participants from 19 studies using LAR. The cancer risks for adults following CT scans were inordinately increased (LAR adults, OR, 10.00 [95% CI, 5.87 to 17.05]; actual adults, OR, 1.17 [95%CI, 0.89 to 1.55]; combined, OR, 5.89 [95%CI, 3.46 to 10.35]). Moreover, cancer risks elevated with increase of radiation dose (OR, 33.31 [95% CI, 21.33 to 52.02]), and multiple CT scan sites (OR, 14.08 [95% CI, 6.60 to 30.05]). The risk of solid malignancy was higher than leukemia. Notably, there were no significant differences for age, gender, country, continent, study quality and studying time phrases. CONCLUSIONS: Based on 111.6 million adult participants from 3 continents (Asia, Europe and America), this meta-analysis identifies an inordinately increase in cancer risks from CT scans for adults. Moreover, the cancer risks were positively correlated with radiation dose and CT sites. The meta-analysis highlights the awareness of potential cancer risks of CT scans as well as more reasonable methodology to quantify cancer risks in terms of life expectancy as 100 years for LAR. PROSPERO TRIAL REGISTRATION NUMBER: CRD42019133487.


Assuntos
Leucemia , Neoplasias , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Masculino , Tomografia Computadorizada por Raios X/efeitos adversos , Neoplasias/diagnóstico por imagem , Neoplasias/epidemiologia , Neoplasias/etiologia , Radiação Ionizante , Razão de Chances
19.
J Clin Ultrasound ; 50(1): 60-69, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34625988

RESUMO

To investigate the diagnostic efficiency of contrast-enhanced ultrasound (CEUS) for the diagnosis of cervical lymph nodes metastasis (CLNM) of papillary thyroid carcinoma (PTC), eight available datasets of seven qualified articles before March 31, 2021 were included after a comprehensive search. Meta-analysis results showed that CEUS demonstrated acceptable diagnostic performance in the diagnosis of CLNM of PTC. Furthermore, meta-regression analysis was conducted to identify the reasons for heterogeneity and the results indicated that the criteria of CEUS for the diagnosis of CLNM in PTC need to be unified.


Assuntos
Neoplasias da Glândula Tireoide , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Estudos Retrospectivos , Fatores de Risco , Câncer Papilífero da Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia
20.
Curr Psychol ; : 1-14, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35990205

RESUMO

China has become one of the leading study abroad destinations worldwide. Recent research also indicates that international students encounter diverse life challenges and mental health issues in China. Therefore, scholars have shown increasing interest in their adjustment in Chinese social and academic settings. Seeking theoretical guidance from the Job Demands-Resources Model with mediation and moderation assumptions, our study aimed to test the dual processes (i.e., the health impairment process and the motivational process) leading to academic, sociocultural, and psychological adjustment, among international students sojourning in China. Using a convenience sampling method, our study recruited 1,001 participants (535 males and 466 females; M age = 22.73; SD = 1.62) who completed an online survey including scales of perceived cultural distance (contextual demands), social support from local members (contextual resources), coping self-efficacy (personal resources), acculturative stress, intercultural engagement, as well as three types of cross-cultural adjustment (academic, sociocultural, and psychological adjustment). Results based on the structural equation modeling (SEM) analyses indicated that perceived cultural distance had indirect relationships with the three types of adjustment through the mediator of acculturative stress. Social support from locals had indirect relationships with the three types of adjustment through the mediators of acculturative stress and intercultural engagement. Coping self-efficacy had indirect relationships with academic and sociocultural adjustment through the mediator of intercultural engagement. Additionally, social support from locals was revealed as a moderator that buffered the relationship between perceived cultural distance and acculturative stress. These mediated and moderated relationships not only confirmed the dual processes underlying international student adjustment, but also added new knowledge of how demands and resources can interplay to predict the dual processes.

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