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1.
EMBO J ; 41(15): e110472, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35686621

RESUMO

Microtubules tightly regulate various cellular activities. Our understanding of microtubules is largely based on experiments using microtubule-targeting agents, which, however, are insufficient to dissect the dynamic mechanisms of specific microtubule populations, due to their slow effects on the entire pool of microtubules. To overcome this technological limitation, we have used chemo and optogenetics to disassemble specific microtubule subtypes, including tyrosinated microtubules, primary cilia, mitotic spindles, and intercellular bridges, by rapidly recruiting engineered microtubule-cleaving enzymes onto target microtubules in a reversible manner. Using this approach, we show that acute microtubule disassembly swiftly halts vesicular trafficking and lysosomal dynamics. It also immediately triggers Golgi and ER reorganization and slows the fusion/fission of mitochondria without affecting mitochondrial membrane potential. In addition, cell rigidity is increased after microtubule disruption owing to increased contractile stress fibers. Microtubule disruption furthermore prevents cell division, but does not cause cell death during interphase. Overall, the reported tools facilitate detailed analysis of how microtubules precisely regulate cellular architecture and functions.


Assuntos
Microtúbulos , Fuso Acromático , Interfase , Microtúbulos/metabolismo , Fuso Acromático/metabolismo
2.
Mol Biol Evol ; 41(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489607

RESUMO

Endolysins are produced by (bacterio)phages and play a crucial role in degrading the bacterial cell wall and the subsequent release of new phage progeny. These lytic enzymes exhibit a remarkable diversity, often occurring in a multimodular form that combines different catalytic and cell wall-binding domains, even in phages infecting the same species. Yet, our current understanding lacks insight into how environmental factors and ecological niches may have influenced the evolution of these enzymes. In this study, we focused on phages infecting Streptococcus thermophilus, as this bacterial species has a well-defined and narrow ecological niche, namely, dairy fermentation. Among the endolysins found in phages targeting this species, we observed limited diversity, with a singular structural type dominating in most of identified S. thermophilus phages. Within this prevailing endolysin type, we discovered a novel and highly conserved calcium-binding motif. This motif proved to be crucial for the stability and activity of the enzyme at elevated temperatures. Ultimately, we demonstrated its positive selection within the host's environmental conditions, particularly under the temperature profiles encountered in the production of yogurt, mozzarella, and hard cheeses that rely on S. thermophilus.


Assuntos
Bacteriófagos , Fagos de Streptococcus , Bacteriófagos/genética , Fermentação , Endopeptidases
3.
PLoS Biol ; 20(8): e3001740, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35913996

RESUMO

Endolysins are produced by (bacterio)phages to rapidly degrade the bacterial cell wall and release new viral particles. Despite sharing a common function, endolysins present in phages that infect a specific bacterial species can be highly diverse and vary in types, number, and organization of their catalytic and cell wall binding domains. While much is now known about the biochemistry of phage endolysins, far less is known about the implication of their diversity on phage-host adaptation and evolution. Using CRISPR-Cas9 genome editing, we could genetically exchange a subset of different endolysin genes into distinct lactococcal phage genomes. Regardless of the type and biochemical properties of these endolysins, fitness costs associated to their genetic exchange were marginal if both recipient and donor phages were infecting the same bacterial strain, but gradually increased when taking place between phage that infect different strains or bacterial species. From an evolutionary perspective, we observed that endolysins could be naturally exchanged by homologous recombination between phages coinfecting a same bacterial strain. Furthermore, phage endolysins could adapt to their new phage/host environment by acquiring adaptative mutations. These observations highlight the remarkable ability of phage lytic systems to recombine and adapt and, therefore, explain their large diversity and mosaicism. It also indicates that evolution should be considered to act on functional modules rather than on bacteriophages themselves. Furthermore, the extensive degree of evolvability observed for phage endolysins offers new perspectives for their engineering as antimicrobial agents.


Assuntos
Bacteriófagos , Bactérias/metabolismo , Bacteriófagos/genética , Parede Celular/metabolismo , Endopeptidases/química , Endopeptidases/genética , Endopeptidases/metabolismo
4.
Neuroimage ; 291: 120593, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38554780

RESUMO

OBJECTIVE: The conventional methods for interpreting tau PET imaging in Alzheimer's disease (AD), including visual assessment and semi-quantitative analysis of fixed hallmark regions, are insensitive to detect individual small lesions because of the spatiotemporal neuropathology's heterogeneity. In this study, we proposed a latent feature-enhanced generative adversarial network model for the automatic extraction of individual brain tau deposition regions. METHODS: The latent feature-enhanced generative adversarial network we propose can learn the distribution characteristics of tau PET images of cognitively normal individuals and output the abnormal distribution regions of patients. This model was trained and validated using 1131 tau PET images from multiple centres (with distinct races, i.e., Caucasian and Mongoloid) with different tau PET ligands. The overall quality of synthetic imaging was evaluated using structural similarity (SSIM), peak signal to noise ratio (PSNR), and mean square error (MSE). The model was compared to the fixed templates method for diagnosing and predicting AD. RESULTS: The reconstructed images archived good quality, with SSIM = 0.967 ± 0.008, PSNR = 31.377 ± 3.633, and MSE = 0.0011 ± 0.0007 in the independent test set. The model showed higher classification accuracy (AUC = 0.843, 95 % CI = 0.796-0.890) and stronger correlation with clinical scales (r = 0.508, P < 0.0001). The model also achieved superior predictive performance in the survival analysis of cognitive decline, with a higher hazard ratio: 3.662, P < 0.001. INTERPRETATION: The LFGAN4Tau model presents a promising new approach for more accurate detection of individualized tau deposition. Its robustness across tracers and races makes it a potentially reliable diagnostic tool for AD in practice.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Proteínas tau/metabolismo , Encéfalo/metabolismo , Disfunção Cognitiva/patologia , Tomografia por Emissão de Pósitrons/métodos
5.
Chembiochem ; 25(14): e202400254, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38757240

RESUMO

In this work, a highly sensitive and selective method for detecting folic acid (FA) was developed using D-penicillamine (DPA) stabilized Ag/Cu alloy nanoclusters (DPA@Ag/Cu NCs). The yellow emission of DPA@Ag/Cu NCs was found to be quenched upon the addition of FA to the system. The fluorescence intensity quenching value demonstrated a linear relationship with FA concentrations ranging from 0.01 to 1200 µM, with a limit of detection (LOD) of 5.3 nM. Furthermore, the detection mechanism was investigated through various characterization analyses, including high resolution transmission electron microscopy, fluorescence spectra, ultraviolet-visible absorption spectra, and fluorescence lifetime. The results indicated that the fluorescence quenching induced by FA was a result of electron transfer from FA to the ligands of DPA@Ag/Cu NCs. The selectivity of the FA sensor was also evaluated, showing that common amino acids and inorganic ions had minimal impact on the detection of FA. Moreover, the standard addition method was successfully applied to detect FA in human serum, chewable tablets and FA tablets with promising results. The use of DPA@Ag/Cu NCs demonstrates significant potential for detecting FA in complex biological samples.


Assuntos
Ligas , Cobre , Corantes Fluorescentes , Ácido Fólico , Penicilamina , Prata , Espectrometria de Fluorescência , Penicilamina/análise , Penicilamina/química , Penicilamina/sangue , Cobre/química , Ácido Fólico/análise , Ácido Fólico/química , Ácido Fólico/sangue , Prata/química , Humanos , Ligas/química , Corantes Fluorescentes/química , Limite de Detecção , Nanopartículas Metálicas/química , Comprimidos/análise
6.
Exp Eye Res ; 240: 109796, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38244883

RESUMO

To investigate the metabolic difference among tissue layers of the rabbits' eye during the development of myopia using metabolomic techniques and explore any metabolic links or cascades within the ocular wall. Ultra Performance Liquid Chromatography - Mass Spectrometry (UPLC-MS) was utilized for untargeted metabolite screening (UMS) to identify the significant differential metabolites produced between myopia (MY) and control (CT) (horizontal). Subsequently, we compared those key metabolites among tissues (Sclera, Choroid, Retina) of MY for distribution and variation (longitudinal). A total of 6285 metabolites were detected in the three tissues. The differential metabolites were screened and the metabolic pathways of these metabolites in each myopic tissue were labeled, including tryptophan and its metabolites, pyruvate, taurine, caffeine metabolites, as well as neurotransmitters like glutamate and dopamine. Our study suggests that multiple metabolic pathways or different metabolites under the same pathway, might act on different parts of the eyeball and contribute to the occurrence and development of myopia by affecting the energy supply to the ocular tissues, preventing antioxidant stress, affecting scleral collagen synthesis, and regulating various neurotransmitters mutually.


Assuntos
Miopia , Espectrometria de Massas em Tandem , Animais , Coelhos , Cromatografia Líquida , Modelos Animais de Doenças , Miopia/metabolismo , Retina/metabolismo , Esclera/metabolismo , Neurotransmissores/metabolismo
7.
Brain Behav Immun ; 121: 155-164, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39043350

RESUMO

Infection by pathogenic microbes is widely hypothesized to be a risk factor for the development of neurocognitive disorders and dementia, but evidence remains limited. We analyzed the association of seropositivity to 11 common pathogens and cumulative infection burden with neurocognitive disorder (mild cognitive impairment and dementia) in a population-based cohort of 475 older individuals (mean age = 67.6 y) followed up over 3-5 years for the risk of MCI-dementia. Specific seropositivities showed a preponderance of positive trends of association with MCI-dementia, including for Plasmodium, H. pylori, and RSV (p < 0.05), as well as Chickungunya, HSV-2, CMV and EBV (p > 0.05), while HSV-1 and HHV-6 showed equivocal or no associations, and Dengue and VZV showed negative associations (p < 0.05) with MCI-dementia. High infection burden (5 + cumulated infections) was significantly associated with an increased MCI-dementia risk in comparison with low infection burden (1-3 cumulative infections), adjusted for age, sex, and education. Intriguingly, for a majority (8 of 11) of pathogens, levels of antibody titers were significantly lower in those with MCI-dementia compared to cognitive normal individuals. Based on our observations, we postulate that individuals who are unable to mount strong immunological responses to infection by diverse microorganisms, and therefore more vulnerable to infection by greater numbers of different microbial pathogens or repeated infections to the same pathogen in the course of their lifetime are more likely to develop MCI or dementia. This hypothesis should be tested in more studies.


Assuntos
Disfunção Cognitiva , Demência , Humanos , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/imunologia , Demência/epidemiologia , Demência/imunologia , Feminino , Masculino , Idoso , Fatores de Risco , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Estudos de Coortes , Infecções/epidemiologia , Infecções/imunologia
8.
Phytother Res ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237123

RESUMO

Gardenia jasminoides Ellis. polysaccharide (GPS) can protect against cholestatic liver injury (CLI) by regulating nuclear farnesoid X receptor (FXR).However, the mechanism via which GPS mediates the FXR pathway remains unclear. The aim of this study was to investigate the mechanism. Firstly, an alpha-naphthylisothiocyanate-induced cholestatic mouse model was administered with GPS to evaluate its hepatoprotective effects. The metabolic pathways influenced by GPS in cholestatic mice were detected by serum metabolomics. The effect of GPS on bile acid (BA) homeostasis, FXR expression, and liver inflammation were investigated. Second, the intestinal bacteria metabolites affected by GPS in vivo and in vitro were determined. The activation of FXR by sodium butyrate (NaB) was measured. Finally, the effects of NaB on cholestatic mice were demonstrated. The main pathways influenced by GPS involved BA biosynthesis. GPS upregulated hepatic FXR expression, improved BA homeostasis, reduced F4/80+ and Ly6G+ positive areas in the liver, and inhibited liver inflammation in cholestatic mice. Butyric acid was the most notable intestinal bacterial metabolite following GPS intervention. NaB activated the transcriptional activity of FXR in vitro, upregulated hepatic FXR and its downstream efflux transporter expression, and ameliorated disordered BA homeostasis in CLI mice. NaB inhibited the toll-like receptor 4/nuclear factor (TLR4/NF-κB) pathway and reduced inflammation and CLI in mice. An FXR antagonist suppressed the effects. In conclusion, GPS increased butyric acid production, which can activate hepatic FXR, reverse BA homeostasis disorder, and inhibit the TLR4/NF-κB inflammatory pathway, exerting protective effects against CLI.

9.
J Assist Reprod Genet ; 41(5): 1233-1243, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38536595

RESUMO

AIM: Abnormalities in oocyte maturation, fertilization, and early embryonic development are major causes of primary infertility in women who are undergoing IVF/ICSI attempts. Although many genetic factors responsible for these abnormal phenotypes have been identified, there are more additional pathogenic genes and variants yet to be discovered. Previous studies confirmed that bi-allelic PATL2 deficiency is an important factor for female infertility. In this study, 935 infertile patients with IVF/ICSI failure were selected for whole-exome sequencing, and 18 probands carrying PATL2 variants with a recessive inheritance pattern were identified. METHODS: We estimated that the prevalence contributed by PATL2 was 1.93% (18/935) in our study cohort. RESULTS: 15 novel variants were found in those families, including c.1093C > T, c.1609dupA, c.1204C > T, c.643dupG, c.877-2A > G, c.1228C > G, c.925G > A, c.958G > A, c.4A > G, c.1258T > C, c.1337G > A, c.1264dupA, c.88G > T, c.1065-2A > G, and c.1271T > C. The amino acids altered by the corresponding variants were highly conserved in mammals, and in silico analysis and 3D molecular modeling suggested that the PATL2 mutants impaired the physiologic function of the resulting proteins. Diverse clinical phenotypes, including oocyte maturation defect, fertilization failure, and early embryonic arrest might result from different variants of PATL2. CONCLUSIONS: These results expand the spectrum of PATL2 variants and provide an important reference for genetic counseling for female infertility, and they increase our understanding of the mechanisms of oocyte maturation arrest caused by PATL2 deficiency.


Assuntos
Sequenciamento do Exoma , Fertilização in vitro , Infertilidade Feminina , Mutação , Proteínas Nucleares , Fenótipo , Proteínas de Ligação a RNA , Injeções de Esperma Intracitoplásmicas , Adulto , Feminino , Humanos , Gravidez , Infertilidade Feminina/genética , Infertilidade Feminina/patologia , Mutação/genética , Oócitos/crescimento & desenvolvimento , Oócitos/patologia , Linhagem , Proteínas Nucleares/genética , Proteínas de Ligação a RNA/genética
10.
Phytother Res ; 38(8): 4151-4167, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39136618

RESUMO

Despite active clinical trials on the use of Oleandrin alone or in combination with other drugs for the treatment of solid tumors, the potential synergistic effect of Oleandrin with radiotherapy remains unknown. This study reveals a new mechanism by which Oleandrin targets ATM and ATR kinase-mediated radiosensitization in lung cancer. Various assays, including clonogenic, Comet, immunofluorescence staining, apoptosis and Cell cycle assays, were conducted to evaluate the impact of oleandrin on radiation-induced double-strand break repair and cell cycle distribution. Western blot analysis was utilized to investigate alterations in signal transduction pathways related to double-strand break repair. The efficacy and toxicity of the combined therapy were assessed in a preclinical xenotransplantation model. Functionally, Oleandrin weakens the DNA damage repair ability and enhances the radiation sensitivity of lung cells. Mechanistically, Oleandrin inhibits ATM and ATR kinase activities, blocking the transmission of ATM-CHK2 and ATR-CHK1 cell cycle checkpoint signaling axes. This accelerates the passage of tumor cells through the G2 phase after radiotherapy, substantially facilitating the rapid entry of large numbers of inadequately repaired cells into mitosis and ultimately triggering mitotic catastrophe. The combined treatment of Oleandrin and radiotherapy demonstrated superior inhibition of tumor proliferation compared to either treatment alone. Our findings highlight Oleandrin as a novel and effective inhibitor of ATM and ATR kinase, offering new possibilities for the development of clinical radiosensitizing adjuvants.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia , Cardenolídeos , Dano ao DNA , Neoplasias Pulmonares , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Animais , Cardenolídeos/farmacologia , Dano ao DNA/efeitos dos fármacos , Linhagem Celular Tumoral , Camundongos , Tolerância a Radiação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Radiossensibilizantes/farmacologia , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto , Reparo do DNA/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células A549
11.
BMC Med Educ ; 24(1): 473, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685015

RESUMO

BACKGROUND: Studies has suggested that receiving social support improves the professional identity of health professional students. According to the two-way social support theory, social support includes receiving social support and giving social support. However, the effect of the two-way social support on health professional students' professional identity has not been clarified yet. METHODS: To explore the mechanism of how two-way social support affects health professional students' professional identity, an observational, cross-sectional study was conducted among a convenience and cluster sample of 1449 health professional students from two medical schools in western China. Measures included a short version of the two-way social support scale, a health professional students' professional identity questionnaire, an achievement motivation scale, and a meaning in life scale. Data were analyzed by use of SPSS26.0 software and PROCESSv4.0 plug-in. RESULTS: Receiving social support, giving social support, achievement motivation, meaning in life, and professional identity were positively correlated with each other. Receiving and giving social support not only directly predicted health professional students' professional identity, but also indirectly predicted health professional students' professional identity through the mediating roles of achievement motivation and meaning in life, and the chain mediating roles of achievement motivation and meaning in life, respectively. The effectiveness of predicting health professional students' professional identity varied among different types of two-way social support, which could be depicted as two-way social support > mainly giving social support > mainly receiving social support > low two-way social support. CONCLUSION: In the medical education, the awareness and ability of health professional students to receive and give social support should be strengthened. More attention should be drawn on the chain mediating effect of achievement motivation and meaning in life between two-way social support and professional identity. The current results shed new light on exploring effective ways of improving health professional students' professional identity, which suggested that more attention should be paid to the positive effects of mainly giving social support and two-way social support rather than only on the effects of receiving social support.


Assuntos
Motivação , Identificação Social , Apoio Social , Humanos , Estudos Transversais , Masculino , Feminino , Adulto Jovem , China , Estudantes de Medicina/psicologia , Adulto , Inquéritos e Questionários , Estudantes de Ciências da Saúde/psicologia
12.
Alzheimers Dement ; 20(9): 6170-6182, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38982860

RESUMO

BACKGROUND: Previous studies have found that Alzheimer's disease (AD)-related plasma markers are associated with amyloid beta (Aß) deposition, but the change of this association in different Aß pathological stages remains unclear. METHODS: Data were obtained from the SILCODE. According to the standardized uptake value ratio (SUVR) and Aß stage classification, correlation analysis was performed among plasma biomarkers, and voxel/SUVR values in the regions of interest (ROI) and clinical scale information, respectively. Mediation analysis was used to study the possible pathways. RESULTS: The proportion of cognitively normal (CN) and subjective cognitive decline (SCD) was the highest in stages A0 to 1, while in stages A2 to 4, the proportion of mild cognitive impairment (MCI) and AD increased. Plasma phosphorylated tau (p-tau)181 and glial fibrillary acidic protein (GFAP) levels were significantly lower in stage A0 compared to the later phases. Two pathways demonstrated fully mediated effects: positron emission tomography (PET) SUVR-plasma p-tau181-Mini-Mental State Examination (MMSE) and PET SUVR-plasma GFAP-MMSE. DISCUSSION: This study demonstrated the role of plasma biomarkers in the early stage of AD, especially in SCD, from both the clinical diagnosis and Aß stage dimensions. HIGHLIGHTS: Plasma ptau181 and GFAP level serve as indicators of early Alzheimer's disease and the pathologic Aß staging classification. A possible ceiling effect of GFAP was observed in the mid-to-late stages of the AD course. This study confirms the role of AD plasma markers in promoting Aß deposition at an early stage, particularly in females with subjective cognitive decline(SCD). The overlapping brain regions of plasma p-tau181, GFAP, and neurofilament light for Aß deposition in the brain in early AD were distributed across various regions, including the posterior cingulate gyrus, rectus gyrus, and inferior temporal gyrus.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Biomarcadores , Encéfalo , Disfunção Cognitiva , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/sangue , Biomarcadores/sangue , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Disfunção Cognitiva/sangue , Proteína Glial Fibrilar Ácida/sangue , Proteína Glial Fibrilar Ácida/metabolismo , Tomografia por Emissão de Pósitrons , Proteínas tau/sangue
13.
Molecules ; 29(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38675611

RESUMO

Obacunone, a natural triterpenoid, is an active component of the herbs Dictamnus dasycarpus Turcz. and Phellodendron amurense Rupr, and an indicator of the herbs' quality. Owing to its multiple health benefits, several studies have investigated the multi-targeting potential action mechanisms of obacunone. To summarize recent developments on the pharmacological actions of obacunone and focus on the underlying molecular mechanisms and signaling networks, we searched PubMed, Europe PMC, Wiley Online Library, Web of Science, Google Scholar, Wanfang Medical Network, and China National Knowledge Infrastructure for articles published prior to March 2024. Existing research indicates obacunone has great potential to become a promising therapeutic option against tumors, fibrotic diseases, bone and cholesterol metabolism diseases, and infections of pathogenic microorganisms, among others. The paper contributes to providing up-to-date references for further research and clinical applications of obacunone.


Assuntos
Compostos Fitoquímicos , Triterpenos , Humanos , Triterpenos/farmacologia , Triterpenos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Animais , Transdução de Sinais/efeitos dos fármacos , Neoplasias/tratamento farmacológico
14.
Molecules ; 29(2)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38257244

RESUMO

Thirty-eight new 4-amino-3,5-dicholo-6-(1H-indazolyl)-2-picolinic acids and 4-amino-3,5-dicholo-6-(2H-indazolyl)-2-picolinic acids were designed by scaffold hopping and synthesized to discover potential herbicidal molecules. All the new compounds were tested to determine their inhibitory activities against Arabidopsis thaliana and the root growth of five weeds. In general, the synthesized compounds exhibited excellent inhibition properties and showed good inhibitory effects on weed root growth. In particular, compound 5a showed significantly greater root inhibitory activity than picloram in Brassica napus and Abutilon theophrasti Medicus at the concentration of 10 µM. The majority of compounds exhibited a 100% post-emergence herbicidal effect at 250 g/ha against Amaranthus retroflexus and Chenopodium album. We also found that 6-indazolyl-2-picolinic acids could induce the up-regulation of auxin genes ACS7 and NCED3, while auxin influx, efflux and auxin response factor were down-regulated, indicating that 6-indazolyl-2-picolinic acids promoted ethylene release and ABA production to cause plant death in a short period, which is different in mode from other picolinic acids.


Assuntos
Arabidopsis , Herbicidas , Herbicidas/farmacologia , Ácidos Picolínicos/farmacologia , Picloram , Transporte Biológico , Ácidos Indolacéticos/farmacologia
15.
Am J Hum Genet ; 107(1): 24-33, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32502391

RESUMO

Zygotic cleavage failure (ZCF) is a unique early embryonic phenotype resulting in female infertility and recurrent failure of in vitro fertilization (IVF) and/or intracytoplasmic sperm injection (ICSI). With this phenotype, morphologically normal oocytes can be retrieved and successfully fertilized, but they fail to undergo cleavage. Until now, whether this phenotype has a Mendelian inheritance pattern and which underlying genetic factors play a role in its development remained to be elucidated. B cell translocation gene 4 (BTG4) is a key adaptor of the CCR4-NOT deadenylase complex, which is involved in maternal mRNA decay in mice, but no human diseases caused by mutations in BTG4 have previously been reported. Here, we identified four homozygous mutations in BTG4 (GenBank: NM_017589.4) that are responsible for the phenotype of ZCF, and we found they followed a recessive inheritance pattern. Three of them-c.73C>T (p.Gln25Ter), c.1A>G (p.?), and c.475_478del (p.Ile159LeufsTer15)-resulted in complete loss of full-length BTG4 protein. For c.166G>A (p.Ala56Thr), although the protein level and distribution of mutant BTG4 was not altered in zygotes from affected individuals or in HeLa cells, the interaction between BTG4 and CNOT7 was abolished. In vivo studies further demonstrated that the process of maternal mRNA decay was disrupted in the zygotes of the affected individuals, which provides a mechanistic explanation for the phenotype of ZCF. Thus, we provide evidence that ZCF is a Mendelian phenotype resulting from mutations in BTG4. These findings contribute to our understanding of the role of BTG4 in human early embryonic development and provide a genetic marker for female infertility.


Assuntos
Proteínas de Ciclo Celular/genética , Infertilidade Feminina/genética , Mutação/genética , Zigoto/patologia , Animais , Linhagem Celular Tumoral , Desenvolvimento Embrionário/genética , Exorribonucleases/genética , Feminino , Células HeLa , Homozigoto , Humanos , Infertilidade Feminina/patologia , Camundongos , Fenótipo , Estabilidade de RNA/genética
16.
Hum Brain Mapp ; 44(3): 1129-1146, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36394351

RESUMO

Exploring individual brain atrophy patterns is of great value in precision medicine for Alzheimer's disease (AD) and mild cognitive impairment (MCI). However, the current individual brain atrophy detection models are deficient. Here, we proposed a framework called generative adversarial network constrained multiple loss autoencoder (GANCMLAE) for precisely depicting individual atrophy patterns. The GANCMLAE model was trained using normal controls (NCs) from the Alzheimer's Disease Neuroimaging Initiative cohort, and the Xuanwu cohort was employed to validate the robustness of the model. The potential of the model for identifying different atrophy patterns of MCI subtypes was also assessed. Furthermore, the clinical application potential of the GANCMLAE model was investigated. The results showed that the model can achieve good image reconstruction performance on the structural similarity index measure (0.929 ± 0.003), peak signal-to-noise ratio (31.04 ± 0.09), and mean squared error (0.0014 ± 0.0001) with less latent loss in the Xuanwu cohort. The individual atrophy patterns extracted from this model are more precise in reflecting the clinical symptoms of MCI subtypes. The individual atrophy patterns exhibit a better discriminative power in identifying patients with AD and MCI from NCs than those of the t-test model, with areas under the receiver operating characteristic curve of 0.867 (95%: 0.837-0.897) and 0.752 (95%: 0.71-0.790), respectively. Similar findings are also reported in the AD and MCI subgroups. In conclusion, the GANCMLAE model can serve as an effective tool for individualised atrophy detection.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Aprendizado Profundo , Humanos , Doença de Alzheimer/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Atrofia/diagnóstico por imagem , Atrofia/patologia
17.
Clin Genet ; 104(4): 461-465, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37211617

RESUMO

Normal oocyte maturation is an important requirement for the success of human reproduction, and defects in this process will lead to female infertility and repeated IVF/ICSI failures. In order to identify genetic factors that are responsible for oocyte maturation defect, we used whole exome sequencing in the affected individual with oocyte maturation defect from a consanguineous family and identified a homozygous variant c.853_861del (p.285_287del) in ZFP36L2. ZFP36L2 is a RNA-binding protein, which regulates maternal mRNA decay and oocyte maturation. In vitro studies showed that the variant caused decreased protein levels of ZFP36L2 in oocytes due to mRNA instability and might lead to the loss of its function to degrade maternal mRNAs. Previous study showed that the pathogenic variants in ZFP36L2 were associated with early embryonic arrest. In contrast, we identified a novel ZFP36L2 variant in the affected individual with oocyte maturation defect, which further broadened the mutational and phenotypic spectrum of ZFP36L2, suggesting that ZFP36L2 might be a genetic diagnostic marker for the affected individuals with oocyte maturation defect.


Assuntos
Infertilidade Feminina , Feminino , Humanos , Infertilidade Feminina/genética , Infertilidade Feminina/patologia , Oócitos/metabolismo , Oogênese/genética , Mutação , Homozigoto , Fatores de Transcrição/genética
18.
Chemphyschem ; 24(20): e202300292, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37491736

RESUMO

The 1 H nuclear magnetic resonance (1 H-NMR) spectrum is a useful tool for characterizing the hydrogen bonding (H-bonding) interactions in ionic liquids (ILs). As the main hydrogen bond (H-bond) donor of imidazolium-based ILs, the chemical shift (δH2 ) of the proton in the 2-position of the imidazolium ring (H2) exhibits significant and complex solvents, concentrations and anions dependence. In the present work, based on the dielectric constants (ϵ) and Kamlet-Taft (KT) parameters of solvents, we identified that the δH2 are dominated by the solvents polarity and the competitive H-bonding interactions between cations and anions or solvents. Besides, the solvents effects on δH2 are understood by the structure of ILs in solvents: 1) In diluted solutions of inoizable solvents, ILs exist as free ions and the cations will form H-bond with solvents, resulting in δH2 being independent with anions but positively correlated with ßS . 2) In diluted solutions of non-ionzable solvents, ILs exist as contact ion-pairs (CIPs) and H2 will form H-bond with anions. Since non-ionizable solvents hardly influence the H-bonding interactions between H2 and anions, the δH2 are not related to ßS but positively correlated with ßIL .

19.
Jpn J Clin Oncol ; 53(3): 221-229, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36533429

RESUMO

OBJECTIVE: First-line pembrolizumab with/without chemotherapy versus chemotherapy was evaluated in programmed death ligand 1 combined positive score ≥1, locally advanced/unresectable or metastatic gastric cancer/gastrooesophageal junction cancer in the KEYNOTE-062 study. We present results for patients enrolled in Asia. METHODS: Eligible patients were randomly assigned 1:1:1 to pembrolizumab 200 mg, pembrolizumab plus chemotherapy (cisplatin + 5-fluorouracil or capecitabine) or placebo plus chemotherapy Q3W. End points included overall survival (primary) in combined positive score ≥1 and combined positive score ≥10 populations and safety and tolerability (secondary). RESULTS: A total of 187 patients were enrolled in Asia (pembrolizumab, n = 62; pembrolizumab plus chemotherapy, n = 64; chemotherapy, n = 61). Compared with the global population, higher proportions of patients had Eastern Cooperative Oncology Group performance status 0 and a diagnosis of stomach cancer. In the programmed death ligand 1 combined positive score ≥1 population, median overall survival was numerically longer with pembrolizumab versus chemotherapy (22.7 vs 13.8 months; hazard ratio, 0.54; 95% confidence interval, 0.35-0.82) and pembrolizumab plus chemotherapy versus chemotherapy (16.5 vs 13.8 months; hazard ratio, 0.78; 95% confidence interval, 0.53-1.16). In the programmed death ligand 1 combined positive score ≥10 population, median overall survival was also numerically longer with pembrolizumab versus chemotherapy (28.5 vs 14.8 months; hazard ratio, 0.43; 95% confidence interval, 0.21-0.89) and pembrolizumab plus chemotherapy versus chemotherapy (17.5 vs 14.8 months; hazard ratio, 0.86; 95% confidence interval, 0.45-1.64). The grade 3-5 treatment-related adverse event rate was 19.4%, 75.8% and 64.9% for patients receiving pembrolizumab, pembrolizumab plus chemotherapy and chemotherapy, respectively. CONCLUSIONS: This post hoc analysis showed pembrolizumab monotherapy was associated with numerically improved overall survival and a favourable tolerability profile versus chemotherapy in Asians with programmed death ligand 1-positive advanced gastric cancer/gastrooesophageal junction cancer.This study is registered with ClinicalTrials.gov, NCT02494583.


Assuntos
Adenocarcinoma , Protocolos de Quimioterapia Combinada Antineoplásica , Padrão de Cuidado , Neoplasias Gástricas , Humanos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Asiático , Cisplatino/uso terapêutico , Junção Esofagogástrica/patologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia
20.
J Med Genet ; 59(9): 840-849, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34544842

RESUMO

BACKGROUND: A large number of new causative and risk genes for amyotrophic lateral sclerosis (ALS) have been identified mostly in patients of European ancestry. In contrast, we know relatively little regarding the genetics of ALS in other ethnic populations. This study aims to provide a comprehensive analysis of the genetics of ALS in an unprecedented large cohort of Chinese mainland population and correlate with the clinical features of rare variants carriers. METHODS: A total of 1587 patients, including 64 familial ALS (FALS) and 1523 sporadic ALS (SALS), and 1866 in-house controls were analysed by whole-exome sequencing and/or testing for G4C2 repeats in C9orf72. Forty-one ALS-associated genes were analysed. FINDINGS: 155 patients, including 26 (40.6%) FALS and 129 (8.5%) SALS, carrying rare pathogenic/likely pathogenic (P/LP) variants of ALS causative genes were identified. SOD1 was the most common mutated gene, followed by C9orf72, FUS, NEK1, TARDBP and TBK1. By burden analysis, rare variants in SOD1, FUS and TARDBP contributed to the collective risk for ALS (p<2.5e-6) at the gene level, but at the allelic level TARDBP p.Gly294Val and FUS p.Arg521Cys and p.Arg521His were the most important single variants causing ALS. Clinically, P/LP variants in TARDBP and C9orf72 were associated with poor prognosis, in FUS linked with younger age of onset, and C9orf72 repeats tended to affect cognition. CONCLUSIONS: Our data provide essential information for understanding the genetic and clinical features of ALS in China and for optimal design of genetic testing and evaluation of disease prognosis.


Assuntos
Esclerose Lateral Amiotrófica , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/genética , Proteína C9orf72/genética , Estudos de Coortes , Predisposição Genética para Doença , Humanos , Mutação/genética , Superóxido Dismutase-1/genética
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