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1.
EMBO Rep ; 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39358552

RESUMO

CHK1 mutations could cause human zygote arrest at the pronuclei stage, a phenomenon that is not well understood at the molecular level. In this study, we conducted experiments where pre-pronuclei from zygotes with CHK1 mutation were transferred into the cytoplasm of normal enucleated fertilized eggs. This approach rescued the zygote arrest caused by the mutation, resulting in the production of a high-quality blastocyst. This suggests that CHK1 dysfunction primarily disrupts crucial biological processes occurring in the cytoplasm. Further investigation reveals that CHK1 mutants have an impact on the F-actin meshwork, leading to disturbances in pronuclear envelope breakdown. Through co-immunoprecipitation and mass spectrometry analysis of around 6000 mouse zygotes, we identified an interaction between CHK1 and MICAL3, a key regulator of F-actin disassembly. The gain-of-function mutants of CHK1 enhance their interaction with MICAL3 and increase MICAL3 enzymatic activity, resulting in excessive depolymerization of F-actin. These findings shed light on the regulatory mechanism behind pronuclear envelope breakdown during the transition from meiosis to the first mitosis in mammals.

2.
Nature ; 579(7798): 284-290, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32103175

RESUMO

Cancer recurrence after surgery remains an unresolved clinical problem1-3. Myeloid cells derived from bone marrow contribute to the formation of the premetastatic microenvironment, which is required for disseminating tumour cells to engraft distant sites4-6. There are currently no effective interventions that prevent the formation of the premetastatic microenvironment6,7. Here we show that, after surgical removal of primary lung, breast and oesophageal cancers, low-dose adjuvant epigenetic therapy disrupts the premetastatic microenvironment and inhibits both the formation and growth of lung metastases through its selective effect on myeloid-derived suppressor cells (MDSCs). In mouse models of pulmonary metastases, MDSCs are key factors in the formation of the premetastatic microenvironment after resection of primary tumours. Adjuvant epigenetic therapy that uses low-dose DNA methyltransferase and histone deacetylase inhibitors, 5-azacytidine and entinostat, disrupts the premetastatic niche by inhibiting the trafficking of MDSCs through the downregulation of CCR2 and CXCR2, and by promoting MDSC differentiation into a more-interstitial macrophage-like phenotype. A decreased accumulation of MDSCs in the premetastatic lung produces longer periods of disease-free survival and increased overall survival, compared with chemotherapy. Our data demonstrate that, even after removal of the primary tumour, MDSCs contribute to the development of premetastatic niches and settlement of residual tumour cells. A combination of low-dose adjuvant epigenetic modifiers that disrupts this premetastatic microenvironment and inhibits metastases may permit an adjuvant approach to cancer therapy.


Assuntos
Epigênese Genética , Terapia Genética , Células Supressoras Mieloides/fisiologia , Neoplasias/terapia , Microambiente Tumoral , Animais , Azacitidina/farmacologia , Benzamidas/farmacologia , Diferenciação Celular , Movimento Celular/efeitos dos fármacos , Quimioterapia Adjuvante , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Camundongos , Células Supressoras Mieloides/citologia , Metástase Neoplásica/terapia , Neoplasias/cirurgia , Piridinas/farmacologia , Receptores CCR2/genética , Receptores de Interleucina-8B/genética , Microambiente Tumoral/efeitos dos fármacos
3.
Mol Psychiatry ; 29(8): 2308-2320, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38459194

RESUMO

Cognitive and behavioral rigidity are observed in various psychiatric diseases, including in autism spectrum disorder (ASD). However, the underlying mechanism remains to be elucidated. In this study, we found that neuroligin-3 (NL3) R451C knockin mouse model of autism (KI mice) exhibited deficits in behavioral flexibility in choice selection tasks. Single-unit recording of medium spiny neuron (MSN) activity in the nucleus accumbens (NAc) revealed altered encoding of decision-related cue and impaired updating of choice anticipation in KI mice. Additionally, fiber photometry demonstrated significant disruption in dynamic mesolimbic dopamine (DA) signaling for reward prediction errors (RPEs), along with reduced activity in medial prefrontal cortex (mPFC) neurons projecting to the NAc in KI mice. Interestingly, NL3 re-expression in the mPFC, but not in the NAc, rescued the deficit of flexible behaviors and simultaneously restored NAc-MSN encoding, DA dynamics, and mPFC-NAc output in KI mice. Taken together, this study reveals the frontostriatal circuit dysfunction underlying cognitive inflexibility and establishes a critical role of the mPFC NL3 deficiency in this deficit in KI mice. Therefore, these findings provide new insights into the mechanisms of cognitive and behavioral inflexibility and potential intervention strategies.


Assuntos
Moléculas de Adesão Celular Neuronais , Cognição , Modelos Animais de Doenças , Dopamina , Proteínas de Membrana , Proteínas do Tecido Nervoso , Núcleo Accumbens , Córtex Pré-Frontal , Animais , Camundongos , Moléculas de Adesão Celular Neuronais/genética , Moléculas de Adesão Celular Neuronais/metabolismo , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiopatologia , Masculino , Dopamina/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Cognição/fisiologia , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/metabolismo , Transtorno do Espectro Autista/fisiopatologia , Neurônios/metabolismo , Recompensa , Corpo Estriado/metabolismo , Técnicas de Introdução de Genes/métodos , Vias Neurais/metabolismo , Vias Neurais/fisiopatologia , Transtorno Autístico/genética , Transtorno Autístico/fisiopatologia , Transtorno Autístico/metabolismo , Camundongos Endogâmicos C57BL , Comportamento de Escolha/fisiologia
4.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38282453

RESUMO

Using a syntactic priming task, we investigated the time course of syntactic encoding in Chinese sentence production and compared encoding patterns between younger and older adults. Participants alternately read sentence descriptions and overtly described pictures, while event-related potentials (ERPs) were recorded. We manipulated the abstract prime structure (active or passive) as well as the lexical overlap of the prime and the target (verb overlap or no overlap). The syntactic choice results replicated classical abstract priming and lexical boost effects in both younger and older adults. However, when production latency was taken into account, the speed benefit from syntactic repetition differed between the two age groups. Meanwhile, preferred priming facilitated production in both age groups, whereas nonpreferred priming inhibited production in the older group. For electroencephalography, an earlier effect of syntactic repetition and a later effect of lexical overlap showed a two-stage pattern of syntactic encoding. Older adults also showed a more delayed and interactive encoding pattern than younger adults, indicating a greater reliance on lexical information. These results are illustrative of the two-stage competition and residual activation models.


Assuntos
Compreensão , Percepção da Fala , Humanos , Idoso , Compreensão/fisiologia , Percepção da Fala/fisiologia , Idioma , Potenciais Evocados/fisiologia , China
5.
Cancer ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141684

RESUMO

BACKGROUND: Infiltrative follicular variant of papillary thyroid carcinoma (IFVPTC) exhibits nuclear characteristics typical of papillary thyroid carcinoma (PTC) but demonstrates a follicular growth pattern. The diagnosis of IFVPTC presenting with atypical nuclear features of PTC poses challenges for both preoperative cytopathology and postoperative histopathology. In such cases, molecular markers are needed to serve as diagnostic aids. Given the limited knowledge of IFVPTC's genomic features, this study aimed to characterize its genetic alterations and identify clinically relevant molecular markers. METHODS: Whole-exome sequencing of 50 IFVPTC tumor-normal pairs identified single-nucleotide variants, somatic copy number alterations (sCNAs), and subclonal architecture. Key mutations were verified via polymerase chain reaction and Sanger sequencing, whereas valuable biomarkers were validated via immunohistochemistry (IHC). RESULTS: This study found that endogenous processes rather than exogenous mutagens dominated the shaping of the genome of IFVPTC during tumorigenesis. BRAF V600E was the only common trunk mutation and significantly mutated gene in IFVPTC. Subcloning analysis found that most IFVPTC samples harbored two or more coexisting clones. sCNA analysis revealed that human leukocyte antigen C (HLA-C) and HLA-A were significantly amplified. Subsequent IHC investigations indicated that HLA-C shows promise in averting the misclassification of challenging-to-interpret IFVPTC and invasive encapsulated follicular variant of PTC (I-EFVPTC) as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). Although there were several similarities between classic PTC and IFVPTC, they differed significantly in their sCNA patterns. CONCLUSIONS: This study provides valuable insights into IFVPTC's genetic alterations and highlights the potential of HLA-C IHC to distinguish challenging-to-interpret IFVPTC and I-EFVPTC from NIFTP, which will enhance the understanding of its molecular features for improved diagnosis and management.

6.
Plant Cell Physiol ; 65(5): 781-789, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38447119

RESUMO

MicroRNAs (miRNAs) are known to play critical roles in regulating rice agronomic traits through mRNA cleavage or translational repression. Our previous study indicated that miR5504 regulates plant height by affecting cell proliferation and expansion. Here, the two independent homozygous mir5504 mutants (CR1 and CR2) and overexpression lines (OE1 and OE2) were further used to investigate the functions of miR5504. The panicle length, 1000-grain weight and grain yield per plant of miR5504-OE lines were identical to those of Nipponbare (NIP), but the 1000-grain weight of mir5504 mutants was reduced by about 10% and 9%, respectively. Meanwhile, the grain width and thickness of mir5504 mutants decreased significantly by approximately 10% and 11%, respectively. Moreover, the cytological results revealed a significant decrease in cell number along grain width direction and cell width in spikelet in mir5504, compared with those in NIP. In addition, several major storage substances of the rice seeds were measured. Compared to NIP, the amylose content of the mir5504 seeds was noticeably decreased, leading to an increase of nearly 10 mm in gel consistency (GC) in mir5504 lines. Further investigation confirmed that LOC_Os08g16914 was the genuine target of miR5504: LOC_Os08g16914 over-expression plants phenocopied the mir5504 mutants. This study provides insights into the role of miR5504 in rice seed development.


Assuntos
Grão Comestível , Regulação da Expressão Gênica de Plantas , MicroRNAs , Oryza , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Mutação , Pleiotropia Genética , Plantas Geneticamente Modificadas , RNA de Plantas/genética , RNA de Plantas/metabolismo , Amilose/metabolismo
7.
Biochem Biophys Res Commun ; 730: 150365, 2024 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-38996786

RESUMO

Epilepsy is a neurological disorder characterized by recurring seizures. It is necessary to further understand the mechanisms of epilepsy in order to develop novel strategies for its prevention and treatment. Abnormal endoplasmic reticulum stress (ERS) activation is related to the pathogenesis of epilepsy. Nuclear protein 1, transcriptional regulator (NUPR1) is involved in ERS and it might play a role in epilepsy progression. In the present study, we generated an epileptic mouse model using pilocarpine induction. After 72 h of pilocarpine treatment, the expression of NUPR1 was increased in epileptic mice. Furthermore, NUPR1 knockdown reduced the number of spontaneous recurrent seizures and alleviated hippocampal damage in these mice. Interestingly, NUPR1 knockdown also reduced the protein expression levels of LC3, PINK1, and Parkin in the mitochondria, and decreased the PINK1 expression in hippocampus. Additionally, the expression of ERS-related proteins-cleaved caspase-12, ATF4, and CHOP-decreased in epileptic mice following NUPR1 knockdown. In vitro experiments showed that the absence of NUPR1 reduced the expression of ATF4, CHOP, and cleaved caspase-12 in hippocampal neurons and inhibited the neuron apoptosis. In all, our study suggested that NUPR1 maybe a potential molecular target for epilepsy therapy.


Assuntos
Estresse do Retículo Endoplasmático , Epilepsia , Hipocampo , Animais , Epilepsia/metabolismo , Epilepsia/genética , Epilepsia/patologia , Camundongos , Masculino , Hipocampo/metabolismo , Hipocampo/patologia , Progressão da Doença , Neurônios/metabolismo , Neurônios/patologia , Apoptose/genética , Técnicas de Silenciamento de Genes , Pilocarpina , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Proteínas de Ligação a DNA , Proteínas de Neoplasias
8.
Brief Bioinform ; 23(2)2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35043153

RESUMO

Genomic epidemiology is important to study the COVID-19 pandemic, and more than two million severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomic sequences were deposited into public databases. However, the exponential increase of sequences invokes unprecedented bioinformatic challenges. Here, we present the Coronavirus GenBrowser (CGB) based on a highly efficient analysis framework and a node-picking rendering strategy. In total, 1,002,739 high-quality genomic sequences with the transmission-related metadata were analyzed and visualized. The size of the core data file is only 12.20 MB, highly efficient for clean data sharing. Quick visualization modules and rich interactive operations are provided to explore the annotated SARS-CoV-2 evolutionary tree. CGB binary nomenclature is proposed to name each internal lineage. The pre-analyzed data can be filtered out according to the user-defined criteria to explore the transmission of SARS-CoV-2. Different evolutionary analyses can also be easily performed, such as the detection of accelerated evolution and ongoing positive selection. Moreover, the 75 genomic spots conserved in SARS-CoV-2 but non-conserved in other coronaviruses were identified, which may indicate the functional elements specifically important for SARS-CoV-2. The CGB was written in Java and JavaScript. It not only enables users who have no programming skills to analyze millions of genomic sequences, but also offers a panoramic vision of the transmission and evolution of SARS-CoV-2.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , Vigilância em Saúde Pública/métodos , SARS-CoV-2/genética , Software , Navegador , Biologia Computacional/métodos , Análise Mutacional de DNA , Bases de Dados Genéticas , Genoma Viral , Genômica , Humanos , Epidemiologia Molecular/métodos , Anotação de Sequência Molecular , Mutação
9.
New Phytol ; 242(2): 576-591, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38362937

RESUMO

Leucine-rich repeat receptor-like kinases (LRR-RLKs) comprise the largest class of membrane-localized receptor-like kinases in plants. Leucine-rich repeat receptor-like kinases are key immune sectors contributing to pattern-triggered immunity (PTI), but whether LRR-RLK mediates effector-triggered immunity (ETI) in plants remains unclear. In this study, we evaluated the function of LRR-RLKs in regulating ETI by using a virus-induced gene silencing (VIGS)-based reverse genetic screening assay, and identified a LRR-RLK named ETI-dependent receptor-like kinase 1 (EDK1) required for ETI triggered by the avirulence effector AVRblb2 secreted by Phytophthora infestans and its cognate receptor Rpi-blb2. Silencing or knockout of EDK1 compromised immunity mediated by Rpi-blb2 and the cell death triggered by recognition of AVRblb2. NLR-required for cell death 4 (NRC4), a signaling component acts downstream of Rpi-blb2, was identified that interacts with EDK1 using the LC-MS analysis and the interaction was further evaluated by co-immunoprecipitation. EDK1 promotes protein accumulation of NRC4 in a kinase-dependent manner and positively regulates resistance to P. infestans in Nicotiana benthamiana. Our study revealed that EDK1 positively regulates plant ETI through modulating accumulation of the NLR signaling component NRC4, representing a new regulatory role of the membrane-localized LRR-RLKs in plant immunity.


Assuntos
Reconhecimento da Imunidade Inata , Nicotiana , Nicotiana/genética , Leucina , Plantas , Imunidade Vegetal , Morte Celular , Doenças das Plantas/genética
10.
FASEB J ; 37(3): e22802, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36786696

RESUMO

Recurrent spontaneous abortion (RSA) is characterized by two or more consecutive pregnancy losses in the first trimester of pregnancy, experienced by 5% of women during their reproductive age. As a complex pathological process, the etiology of RSA remains poorly understood. Recent studies have established that gene expression changes dramatically in human endometrial stromal cells (ESCs) during decidualization. N6-methyladenosine (m6 A) modification is the most prevalent epigenetic modification of mRNA in eukaryotic cells and it is closely related to the occurrence and development of many pathophysiological phenomena. In this study, we first confirmed that high levels of m6 A mRNA methylation in decidual tissues are associated with RSA. Then, we used m6 A-modified RNA immunoprecipitation sequence (m6 A-seq) and RNA sequence (RNA-seq) to identify the differentially expressed m6 A methylation in decidual tissues from RSA patients and identified the key genes involved in abnormal decidualization by bioinformatics analysis. Using m6 A-seq, we identified a total of 2169 genes with differentially expressed m6 A methylation, of which 735 m6 A hypermethylated genes and 1434 m6 A hypomethylated genes were identified. Further joint analysis of m6 A-seq and RNA-seq revealed that 133 genes were m6 A modified with mRNA expression. GO and KEGG analyses indicated that these unique genes were mainly enriched in environmental information processing pathways, including the cytokine-cytokine receptor interaction and PI3K-Akt signaling pathway. In summary, this study uncovered the transcriptome-wide m6 A modification pattern in decidual tissue of RSA, which provides a theoretical basis for further research into m6 A modification and new therapeutic strategies for RSA.


Assuntos
Aborto Habitual , Fosfatidilinositol 3-Quinases , Gravidez , Humanos , Feminino , Metilação , Transcriptoma , Adenosina/genética
11.
PLoS Biol ; 19(6): e3001239, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34138843

RESUMO

Hypoxia drives aging and promotes age-related cognition and hearing functional decline. Despite the role of erythrocytes in oxygen (O2) transport, their role in the onset of aging and age-related cognitive decline and hearing loss (HL) remains undetermined. Recent studies revealed that signaling through the erythrocyte adenosine A2B receptor (ADORA2B) promotes O2 release to counteract hypoxia at high altitude. However, nothing is known about a role for erythrocyte ADORA2B in age-related functional decline. Here, we report that loss of murine erythrocyte-specific ADORA2B (eAdora2b-/-) accelerates early onset of age-related impairments in spatial learning, memory, and hearing ability. eAdora2b-/- mice display the early aging-like cellular and molecular features including the proliferation and activation of microglia and macrophages, elevation of pro-inflammatory cytokines, and attenuation of hypoxia-induced glycolytic gene expression to counteract hypoxia in the hippocampus (HIP), cortex, or cochlea. Hypoxia sufficiently accelerates early onset of cognitive and cochlear functional decline and inflammatory response in eAdora2b-/- mice. Mechanistically, erythrocyte ADORA2B-mediated activation of AMP-activated protein kinase (AMPK) and bisphosphoglycerate mutase (BPGM) promotes hypoxic and metabolic reprogramming to enhance production of 2,3-bisphosphoglycerate (2,3-BPG), an erythrocyte-specific metabolite triggering O2 delivery. Significantly, this finding led us to further discover that murine erythroblast ADORA2B and BPGM mRNA levels and erythrocyte BPGM activity are reduced during normal aging. Overall, we determined that erythrocyte ADORA2B-BPGM axis is a key component for anti-aging and anti-age-related functional decline.


Assuntos
Vias Auditivas/fisiopatologia , Disfunção Cognitiva/metabolismo , Eritrócitos/metabolismo , Hipóxia/metabolismo , Receptor A2B de Adenosina/metabolismo , 2,3-Difosfoglicerato/metabolismo , Envelhecimento/patologia , Animais , Bisfosfoglicerato Mutase/genética , Bisfosfoglicerato Mutase/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Cóclea/fisiopatologia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/genética , Disfunção Cognitiva/fisiopatologia , Ativação Enzimática , Deleção de Genes , Glicólise , Hipóxia/complicações , Hipóxia/genética , Hipóxia/fisiopatologia , Inflamação/complicações , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/patologia , Receptor A2B de Adenosina/deficiência
12.
Diabetes Obes Metab ; 26(8): 3088-3098, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38698651

RESUMO

AIM: Fluoroquinolone-related hypoglycaemia is rare but may become clinically relevant in individuals at high baseline hypoglycaemic risk, such as patients with diabetes using sulphonylureas. Our population-based cohort study assessed whether fluoroquinolones are associated with an increased risk of severe hypoglycaemia compared with amoxicillin among patients treated with sulphonylureas. MATERIALS AND METHODS: Using the UK's Clinical Practice Research Datalink Aurum linked to hospitalization and vital statistics data, we assembled a base cohort of patients who initiated second-generation sulphonylureas (1998-2020). The study cohort included patients initiating either fluoroquinolones or amoxicillin while on sulphonylureas. Using an intent-to-treat exposure definition, we assessed the 30-day risk of severe hypoglycaemia (hospitalization with or death because of hypoglycaemia) associated with fluoroquinolones compared with amoxicillin. Cox models estimated hazard ratios (HRs) with 95% confidence intervals (CIs) of severe hypoglycaemia after 1:5 matching on previous sulphonylurea use and propensity scores. Secondary analyses were stratified by demographics and glycated haemoglobin. RESULTS: Overall, 143 417 patients initiated fluoroquinolones (n = 13 123) or amoxicillin (n = 130 294) while on sulphonylureas. Compared with amoxicillin, fluoroquinolones were not associated with the risk of severe hypoglycaemia (HR, 1.17; 95% CI, 0.91-1.50). Fluoroquinolones were associated with an increased risk in patients <65 years (HR, 2.90; 95% CI, 1.41-5.97) but not in those ≥65 years (HR, 1.03; 95% CI, 0.79-1.35) in stratified analyses. There was no evidence of effect modification by sex or glycated haemoglobin. CONCLUSIONS: In patients using second-generation sulphonylureas, fluoroquinolones were not associated with an increased risk of severe hypoglycaemia compared with amoxicillin. An increased risk among younger adults is possible.


Assuntos
Diabetes Mellitus Tipo 2 , Fluoroquinolonas , Hipoglicemia , Hipoglicemiantes , Compostos de Sulfonilureia , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemia/epidemiologia , Compostos de Sulfonilureia/efeitos adversos , Feminino , Fluoroquinolonas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Idoso , Estudos de Coortes , Hipoglicemiantes/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Amoxicilina/efeitos adversos , Reino Unido/epidemiologia , Fatores de Risco , Adulto , Antibacterianos/efeitos adversos
13.
Phys Chem Chem Phys ; 26(14): 10515-10519, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38526518

RESUMO

Förster resonance energy transfer (FRET) holds a significant position in various natural and artificial systems, especially within donor-acceptor systems encompassing chiral components. Despite extensive investigations, a clear understanding of the effects of chirality and FRET on discriminatory fluorescence remains elusive. Here, chiral perovskite nanowires (CPNWs) and achiral rhodamine B (RhB) are employed to examine the FRET and discriminatory fluorescence behavior in a donor-acceptor system involving a chiral nanostructure. A notable FRET from the CPNWs to RhB is observed, along with circular dichroism (CD) and circularly polarized luminescence (CPL) activities in RhB. Although the FRET interaction remains consistent over time, a notable inversion in the polarity preference of the CD and CPL of RhB is observed. This reveals that the discriminatory fluorescence of the acceptor arises from the electromagnetic influence of the chiral donor. These findings elucidate that "chirality", as a property related to spatial orientation, cannot accompany the transfer of energy (which is a scalar) from chiral nanostructures to achiral molecules, which helps advance the understanding of the discriminatory fluorescence in the donor-acceptor system with a chiral nanostructure.

14.
J Biomed Inform ; 151: 104620, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38462064

RESUMO

OBJECTIVE: Large language models (LLMs) such as ChatGPT are increasingly explored in medical domains. However, the absence of standard guidelines for performance evaluation has led to methodological inconsistencies. This study aims to summarize the available evidence on evaluating ChatGPT's performance in answering medical questions and provide direction for future research. METHODS: An extensive literature search was conducted on June 15, 2023, across ten medical databases. The keyword used was "ChatGPT," without restrictions on publication type, language, or date. Studies evaluating ChatGPT's performance in answering medical questions were included. Exclusions comprised review articles, comments, patents, non-medical evaluations of ChatGPT, and preprint studies. Data was extracted on general study characteristics, question sources, conversation processes, assessment metrics, and performance of ChatGPT. An evaluation framework for LLM in medical inquiries was proposed by integrating insights from selected literature. This study is registered with PROSPERO, CRD42023456327. RESULTS: A total of 3520 articles were identified, of which 60 were reviewed and summarized in this paper and 17 were included in the meta-analysis. ChatGPT displayed an overall integrated accuracy of 56 % (95 % CI: 51 %-60 %, I2 = 87 %) in addressing medical queries. However, the studies varied in question resource, question-asking process, and evaluation metrics. As per our proposed evaluation framework, many studies failed to report methodological details, such as the date of inquiry, version of ChatGPT, and inter-rater consistency. CONCLUSION: This review reveals ChatGPT's potential in addressing medical inquiries, but the heterogeneity of the study design and insufficient reporting might affect the results' reliability. Our proposed evaluation framework provides insights for the future study design and transparent reporting of LLM in responding to medical questions.


Assuntos
Inteligência Artificial , Comunicação , Bases de Dados Factuais , Reprodutibilidade dos Testes
15.
J Biochem Mol Toxicol ; 38(4): e23676, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38561971

RESUMO

Although the treatment of ovarian cancer has made great progress, there are still many patients who are not timely detected and given targeted therapy due to unknown pathogenesis. Recent studies have found that hsa_circ_0015326 is upregulated in ovarian cancer and is involved in the proliferation, invasion, and migration of ovarian cancer cells. However, whether hsa_circ_0015326 can be used as a new target of ovarian cancer needs further investigation. Therefore, the effect of hsa_circ_0015326 on epithelial ovarian cancer was investigated in this study. At first, si-hsa_circ_0015326 lentivirus was transfected into epithelial ovarian cancer cells. Then real-time fluorescence quantitative PCR (qRT-PCR) was used to detect hsa_circ_0015326 level. The proliferation of ovarian cancer cells was detected by CCK-8 assay. The horizontal and vertical migration abilities of the cells were detected by wound-healing assay and Transwell assay, respectively. Transwell assay was also used to determine the invasion rate. As for the apoptosis rate, it was assessed by flow cytometry. As a result, the expression level of hsa_circ_0015326 in A2780 and SKOV3 was found to be higher than that in IOSE-80. However, after transfecting si-hsa_circ_0015326 and si-NC into the cells, the proliferation, migration, and invasion abilities of A2780 and SKOV3 cells in the si-hsa_circ_0015326 group were significantly reduced in comparison to those in the si-NC and mock groups, while their apoptosis rates were elevated. Collectively, silencing hsa_circ_0015326 bears the capability of inhibiting the proliferation, migration, and invasion of ovarian cancer cells while increasing apoptosis rate. It can be concluded that hsa_circ_0015326 promotes the malignant biological activities of epithelial ovarian cancer cells.


Assuntos
MicroRNAs , Neoplasias Ovarianas , Humanos , Feminino , RNA/metabolismo , Carcinoma Epitelial do Ovário/genética , RNA Circular/genética , RNA Circular/metabolismo , Linhagem Celular Tumoral , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Proliferação de Células , Apoptose , MicroRNAs/metabolismo , Movimento Celular
16.
BMC Cardiovasc Disord ; 24(1): 588, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39455943

RESUMO

OBJECTIVE: This study aimed to investigate the risk factors affecting the presence of carotid plaque in asymptomatic adults. METHODS: Asymptomatic adults (age > 40 years, no symptoms of cardiovascular and cerebrovascular diseases) undergoing routine health examinations from physical examination department were included in this study. Carotid plaque was measured by Resona 7OB and Resona 8EXP color Doppler ultrasound and L9-3U and L4-5WU probes. The focal carotid intima-media thickness was greater than 1.1 mm, and the local protrusion of the artery wall into the artery lumen suggested the presence of carotid atherosclerotic plaque. According to their ultrasound results, 1077 asymptomatic adults were divided into a group with carotid plaque (477) and a group without carotid plaque (600). RESULTS: A total of 1077 asymptomatic adults were included in this study, of whom 44.3% had carotid plaque. The proportion of men with carotid plaque was 84.5%. Multifactorial logistic analysis suggested that age, fasting blood glucose (FBG), total cholesterol (TC), homocysteine (Hcy) and male gender were risk factors for carotid atherosclerosis. The predictive probability of these risk factor indicators derived from the multifactorial model was calculated using receiver operating characteristic (ROC) curves with SPSS 25.0 software. The calculated area under the receiver operating characteristic curve (AUC) was 0.715 (95% CI, 0.685-0.746). CONCLUSION: Age, FBG, TC, Hcy and male gender are risk factors for carotid atherosclerosis in asymptomatic adults. Gender differences in carotid atherosclerosis deserve further attention.


Assuntos
Doenças Assintomáticas , Doenças das Artérias Carótidas , Espessura Intima-Media Carotídea , Placa Aterosclerótica , Valor Preditivo dos Testes , Ultrassonografia Doppler em Cores , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/epidemiologia , Medição de Risco , Fatores de Risco , Adulto , Idoso , Fatores Sexuais , Fatores Etários , Biomarcadores/sangue , Glicemia/metabolismo , Colesterol/sangue , Homocisteína/sangue , Estudos Transversais
17.
Pharmacoepidemiol Drug Saf ; 33(10): e70014, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39375929

RESUMO

PURPOSE: The optimal design for pharmacoepidemiologic drug-drug interactions (DDIs) studies is unclear. Using the association between concomitant use of sulfonylureas and warfarin and the risk of severe hypoglycemia as a case study, a DDI with little or no clinical impact, we tested whether the prevalent new-user design can be applied in the area. METHODS: Among all patients initiating sulfonylureas in the UK's Clinical Practice Research Datalink (1998-2020), we identified those adding-on warfarin while on a sulfonylurea. For each co-exposed patient, we defined a prescription-based exposure set including other sulfonylurea users not adding-on warfarin (comparators). Within each exposure set, we matched each co-exposed patient to five comparators on time-conditional propensity scores (TCPS) and followed them using an as-treated approach. Cox proportional hazards models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) of severe hypoglycemia associated with concomitant use of sulfonylureas and warfarin compared to use of sulfonylureas alone. Sensitivity analyses addressed the impact of different potential sources of bias. RESULTS: The study cohort included 17 890 patients co-exposed to sulfonylureas and warfarin and 88 749 matched comparators. After TCPS matching, patient characteristics were well-balanced between groups. Compared to use of sulfonylureas alone, concomitant use of sulfonylureas and warfarin was not associated with the risk of severe hypoglycemia (HR, 1.04; 95% CI, 0.92-1.17). Sensitivity analyses were consistent with the primary analysis (HRs ranging from 1.01 to 1.15, all not statistically significant). CONCLUSIONS: Our study suggests that the prevalent new-user design could be used for the assessment of clinical effects of DDIs.


Assuntos
Anticoagulantes , Interações Medicamentosas , Hipoglicemia , Hipoglicemiantes , Compostos de Sulfonilureia , Varfarina , Humanos , Varfarina/efeitos adversos , Varfarina/administração & dosagem , Compostos de Sulfonilureia/efeitos adversos , Hipoglicemia/induzido quimicamente , Hipoglicemia/epidemiologia , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Anticoagulantes/efeitos adversos , Anticoagulantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/administração & dosagem , Farmacoepidemiologia/métodos , Reino Unido/epidemiologia , Projetos de Pesquisa , Bases de Dados Factuais , Idoso de 80 Anos ou mais , Modelos de Riscos Proporcionais , Pontuação de Propensão
18.
Acta Pharmacol Sin ; 45(3): 517-530, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37880339

RESUMO

Malignant ventricular arrhythmia (VA) after myocardial infarction (MI) is mainly caused by myocardial electrophysiological remodeling. Brahma-related gene 1 (BRG1) is an ATPase catalytic subunit that belongs to a family of chromatin remodeling complexes called Switch/Sucrose Non-Fermentable Chromatin (SWI/SNF). BRG1 has been reported as a molecular chaperone, interacting with various transcription factors or proteins to regulate transcription in cardiac diseases. In this study, we investigated the potential role of BRG1 in ion channel remodeling and VA after ischemic infarction. Myocardial infarction (MI) mice were established by ligating the left anterior descending (LAD) coronary artery, and electrocardiogram (ECG) was monitored. Epicardial conduction of MI mouse heart was characterized in Langendorff-perfused hearts using epicardial optical voltage mapping. Patch-clamping analysis was conducted in single ventricular cardiomyocytes isolated from the mice. We showed that BRG1 expression in the border zone was progressively increased in the first week following MI. Cardiac-specific deletion of BRG1 by tail vein injection of AAV9-BRG1-shRNA significantly ameliorated susceptibility to electrical-induced VA and shortened QTc intervals in MI mice. BRG1 knockdown significantly enhanced conduction velocity (CV) and reversed the prolonged action potential duration in MI mouse heart. Moreover, BRG1 knockdown improved the decreased densities of Na+ current (INa) and transient outward potassium current (Ito), as well as the expression of Nav1.5 and Kv4.3 in the border zone of MI mouse hearts and in hypoxia-treated neonatal mouse ventricular cardiomyocytes. We revealed that MI increased the binding among BRG1, T-cell factor 4 (TCF4) and ß-catenin, forming a transcription complex, which suppressed the transcription activity of SCN5A and KCND3, thereby influencing the incidence of VA post-MI.


Assuntos
Infarto do Miocárdio , Camundongos , Animais , Infarto do Miocárdio/metabolismo , Arritmias Cardíacas/genética , Miocárdio/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Miócitos Cardíacos/metabolismo
19.
Environ Res ; 258: 119461, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38909945

RESUMO

Microaerobic sludge bed systems could align with low-energy, reasonable carbon-nitrogen (C/N) ratio, and synchronous removal objectives during wastewater treatment. However, its ability to treat municipal wastewater (MW) with varying low C/N ratio, low NH4+ concentration, along with managing sludge bulking and loss are still unclear. Against this backdrop, this study investigated the performance of an Upflow Microaerobic Sludge Bed Reactor (UMSR) treating MW characterized by varying low C/N ratios and low NH4+ concentrations. The study also thoroughly examined associated sludge bulking and loss, pollutant removal efficiencies, sludge settleability, microbial community structures, functional gene variations, and metabolic pathways. Findings revealed that the effluent NH4+-N concentration gradually decreased to 0 mg/L with a decrease in the C/N ratio, whereas the effluent COD was unaffected by the influent, maintaining a concentration below 50 mg/L. Notably, TN removal efficiency reached 90% when C/N ratio was 3. The decrease in the C/N ratio (C/N ratio was 1) increased microbial community diversity, with abundances of AOB, AnAOB, aerobic denitrifying bacteria, and anaerobic digestion bacteria reaching 8.34%, 0.96%, 5.07%, and 9.01%, respectively. Microorganisms' metabolic pathways significantly shifted, showing increased carbohydrate and cofactor/vitamin metabolism and decreased amino acid metabolism and xenobiotic biodegradation. This study not only provides a solution for the effluent of different pre-capture carbon processes but also demonstrates the UMSR's capability in managing low C/N ratio municipal wastewater and emphasizes the critical role of microbial community adjustments and functional gene variations in enhancing nitrogen removal efficiency.


Assuntos
Reatores Biológicos , Carbono , Nitrogênio , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias , Nitrogênio/metabolismo , Nitrogênio/análise , Carbono/análise , Carbono/metabolismo , Eliminação de Resíduos Líquidos/métodos , Esgotos/microbiologia , Esgotos/química , Reatores Biológicos/microbiologia , Águas Residuárias/microbiologia , Águas Residuárias/química , Microbiota , Bactérias/metabolismo , Bactérias/genética , Bactérias/classificação , Aerobiose
20.
Clin Trials ; 21(5): 541-552, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39114952

RESUMO

Duration of response is an important endpoint used in drug development. Prolonged duration for response is often viewed as an early indication of treatment efficacy. However, there are numerous difficulties in studying the distribution of duration of response based on observed data subject to right censoring in practice. The most important obstacle is that the distribution of the duration of response is in general not identifiable in the presence of censoring due to the simple fact that there is no information on the joint distribution of time to response and time to progression beyond the largest follow-up time. In this article, we introduce the restricted duration of response as a replacement of the conventional duration of response. The distribution of restricted duration of response is estimable and we have proposed several nonparametric estimators in this article. The corresponding inference procedure and additional downstream analysis have been developed. Extensive numerical simulations have been conducted to examine the finite sample performance of the proposed estimators. It appears that a new regression-based two-step estimator for the survival function of the restricted duration of response tends to have a robust and superior performance, and we recommend its use in practice. A real data example from oncology has been used to illustrate the analysis for restricted duration of response.


Assuntos
Simulação por Computador , Humanos , Fatores de Tempo , Modelos Estatísticos , Interpretação Estatística de Dados , Resultado do Tratamento , Projetos de Pesquisa , Estatísticas não Paramétricas , Determinação de Ponto Final
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