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Actively dividing cells perform robust and accurate DNA replication during fluctuating nutrient availability, yet factors that prevent disruption of replication remain largely unknown. Here we report that DksA, a nutrient-responsive transcription factor, ensures replication completion in Escherichia coli by removing transcription roadblocks. In the absence of DksA, replication is rapidly arrested upon amino acid starvation. This arrest requires active transcription and is alleviated by RNA polymerase mutants that compensate for DksA activity. This replication arrest occurs independently of exogenous DNA damage, yet it induces the DNA-damage response and recruits the main recombination protein RecA. This function of DksA is independent of its transcription initiation activity but requires its less-studied transcription elongation activity. Finally, GreA/B elongation factors also prevent replication arrest during nutrient stress. We conclude that transcription elongation factors alleviate fundamental conflicts between replication and transcription, thereby protecting replication fork progression and DNA integrity.
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Replicação do DNA , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Transcrição Gênica , Aminoácidos/metabolismo , Dano ao DNA , Reparo do DNA , Guanosina Pentafosfato/metabolismoRESUMO
Revealing the in-depth structure-property relationship and designing specific capacity electrodes are particularly important for supercapacitors. Despite many efforts made to tune the composition and electronic structure of cobalt oxide for pseudocapacitance, insight into the [CoO]6 octahedron from the microstructure is still insufficient. Herein, we present a tunable [CoO]6 octahedron microstructure in LiCoO2 by a chemical delithiation process. The c-strained strain of the [CoO]6 octahedron is induced to form higher valence Co ions, and the (003) crystalline layer spacing increases to allow more rapid participation of OH- in the redox reaction. Interestingly, the specific capacity of L0.75CO2 is nearly four times higher than that of LiCoO2 at 10 mA g-1. The enhanced activity originated from the asymmetric strain [CoO]6 octahedra, resulting in enhanced electronic conductivity and Co-O hybridization for accelerated redox kinetics. This finding provides new insights into the modification strategy for pseudocapacitive transition metal oxides.
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A scheme is proposed to achieve significantly enhanced quantum estimation of optorotational-coupling (ORC) strength by coupling a driven auxiliary cavity to a Laguerre-Gaussian (L-G) rotational cavity, where the ORC originates from the exchange of orbital angular momentum between a L-G light and rotational mirror. The results indicate that, by appropriately designing the auxiliary-cavity mechanism, the estimation error of the ORC parameter is significantly reduced, and revealing the estimation precision has a much stronger thermal noise and dissipation robustness in comparison with the unassisted case. Our study paves the way toward achieving high-precision quantum sensors.
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The detrimental impact of noise on sensing performance in quantum metrology has been widely recognized by researchers in the field. However, there are no explicit fundamental laws of physics stating that noise invariably weakens quantum metrology. We reveal that phase-covariant noise either degrades or remains neutral to sensing precision, whereas non-phase-covariant noise can potentially enhance parameter estimation, surpassing even the ultimate precision limit achievable in the absence of noise. This implies that a non-Hermitian quantum sensor may outperform its Hermitian counterpart in terms of sensing performance. To illustrate and validate our theory, we present several paradigmatic examples of magnetic field metrology.
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Encapsulation of transition metals represents a crucial method for modifying the electronic structure and regulating the reactivity of fullerene, thereby expanding its applications. Herein, we present calculations with density functional theory methods to investigate the mechanisms of the Diels-Alder (DA) reactions of cyclopentadiene and La@C60 or Gd@C60 as well as their tricationic derivatives. Our findings indicate that the encapsulation of La and Gd into the C60 cage is thermodynamically favorable. The DA reactions are favored by the presence of La and Gd, with lower barriers, though the regioselectivity, favoring 6-6 bonds in the fullerene, is not affected. The effect of external electric fields has been also considered.
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KEY MESSAGE: Integrated phenomics, ionomics, genomics, transcriptomics, and functional analyses present novel insights into the role of pectin demethylation-mediated cell wall Na+ retention in positively regulating salt tolerance in oilseed rape. Genetic variations in salt stress tolerance identified in rapeseed genotypes highlight the complicated regulatory mechanisms. Westar is ubiquitously used as a transgenic receptor cultivar, while ZS11 is widely grown as a high-production and good-quality cultivar. In this study, Westar was found to outperform ZS11 under salt stress. Through cell component isolation, non-invasive micro-test, X-ray energy spectrum analysis, and ionomic profile characterization, pectin demethylation-mediated cell wall Na+ retention was proposed to be a major regulator responsible for differential salt tolerance between Westar and ZS11. Integrated analyses of genome-wide DNA variations, differential expression profiling, and gene co-expression networks identified BnaC9.PME47, encoding a pectin methylesterase, as a positive regulator conferring salt tolerance in rapeseed. BnaC9.PME47, located in two reported QTL regions for salt tolerance, was strongly induced by salt stress and localized on the cell wall. Natural variation of the promoter regions conferred higher expression of BnaC9.PME47 in Westar than in several salt-sensitive rapeseed genotypes. Loss of function of AtPME47 resulted in the hypersensitivity of Arabidopsis plants to salt stress. The integrated multiomics analyses revealed novel insights into pectin demethylation-mediated cell wall Na+ retention in regulating differential salt tolerance in allotetraploid rapeseed genotypes. Furthermore, these analyses have provided key information regarding the rapid dissection of quantitative trait genes responsible for nutrient stress tolerance in plant species with complex genomes.
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Arabidopsis , Brassica napus , Brassica rapa , Tolerância ao Sal/genética , Brassica napus/genética , Pectinas , Estresse Salino , Parede Celular , DesmetilaçãoRESUMO
OBJECTIVE: The objective was to present our experience on managing mycotic infrarenal abdominal aortic aneurysm (MIAAA) through a retrospective cohort study. METHODS: Data of patients with MIAAA managed in our center from July 2016 to October 2022 were retrospectively analyzed. The diagnosis of MIAAA was made based on: (1) preoperative clinical signs of infection; (2) elevated serologic infection parameters; (3) para-aneurysmal infection features on enhanced computed tomography; and (4) positive blood or tissue cultures. All the patients received standard antibiotic therapy. Surgical management including endovascular aneurysm repair (EVAR), initial EVAR followed by open re-operation, and initial open surgical repair (OSR) were conducted according to disease seriosity, physical condition, and patient's will. Infection index and clinical outcome were evaluated during the follow-up time. RESULTS: A total of 23 patients (21 men; averaged=66.3 years, range=49-79 years) were included, with a mean follow-up time of 19.9 months (range=1-75 months). Bacteria culture from blood or tissue specimen was positive in 15 patients (Salmonella, n=8; Escherichia coli, n=3; methicillin-sensitive Staphylococcus aureus [MSSA], n=1; Klebsiella pneumoniae, n=1; Staphylococcus epidermidis, n=1; Mycobacterium tuberculosis, n=1). Seven patients received OSR as the initial surgical intervention, whereas 14 patients chose EVAR instead. The 2 conservatively managed patients (refused surgery) died within 30 days. The 7 patients who received initial OSR survived till now. Among the 14 patients who underwent initial EVAR, infection deteriorated without exception (14/14, 100%). Three of these patients refused re-operation and died within 6 months. Eleven patients received secondary surgical intervention (10 cases of aneurysm and endograft resection, thorough debridement, subclavian to bi-femoral artery bypass, or in situ aorta reconstruction; 1 case of laparoscopic debridement) and 7 survived the follow-up time. The overall mortality rate was 39.1% (9/23). The mortality rates differed greatly following different intervention methods (merely antibiotic management, 100%; initial open operation, 0%; initial EVAR without secondary operation, 100%; initial EVAR plus secondary operation, 36.4%). CONCLUSIONS: Open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely EVAR is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary OSR. CLINICAL IMPACT: The management of mycotic or primary-infected aortic aneurysm is challenging; treatment remains controversial. Our center has reviewed our experience over the past 6 years and found that open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely endovascular aneurysm repair (EVAR) is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary open surgical repair.
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Nowadays, easy, convenient, and sensitive sensing strategies are still critical for organophosphorus pesticides in environmental water samples. Herein, a novel organophosphorus pesticide (OP) assay based on acetylcholinesterase (AChE) and a MnO2 nanosheet-mediated CRISPR/Cas12a reaction is reported. The single-strand DNA (ssDNA) activator of CRISPR/Cas12a was simply adsorbed on the MnO2 nanosheets as the nanoswitches of the assay. In the absence of target OPs, AChE hydrolyzed acetylcholine (ATCh) to thiocholine (TCh), which reduced the MnO2 nanosheets to Mn2+, resulting in the release of the activator followed by activation of the CRISPR/Cas12a system. The activated Cas12a thereafter nonspecifically cleaved the FAM/BHQ1-labeled ssDNA (FQ-reporter), producing a fluorescence signal. Upon the addition of target OPs, the hydrolysis of ATCh by AChE was inhibited owing to OPs combining with AChE, and thus effective quantification of OPs could be achieved by measuring the fluorescence changes of the system. As a proof of concept, dichlorvos (DDVP) was chosen as a model OP analyte to address the feasibility of the proposed method. Attributed to the excellent trans-cleavage activity of Cas12a, the fluorescent biosensor exhibits a satisfactory limit of detection (LOD) for DDVP at 0.135 ng mL-1. In addition, the excellent recoveries for the detection of DDVP in environmental water samples demonstrate the applicability of the proposed assay in real sample research.
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Técnicas Biossensoriais , Praguicidas , Praguicidas/análise , Compostos Organofosforados , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Sistemas CRISPR-Cas , Diclorvós , Água , Compostos de Manganês , Óxidos , Acetilcolina , Técnicas Biossensoriais/métodosRESUMO
The large yellow croaker (Larimichthys crocea) stands as a cornerstone of mariculture in China due to its significant value. However, the threat of Pseudomonas plecoglossicida infection looms large, capable of triggering "visceral white spot disease" and subsequently inflicting severe economic ramifications. Through a prior genome-wide association analysis (GWAS) aimed at understanding the resistance of the large yellow croaker to this ailment, a pivotal player emerged: the complement component 1q binding protein, aptly named LcC1qbp. This protein assumes a crucial role in the activation of the complement system. This study delves deeper into the immune response by examining the expression patterns of LcC1QBP when confronted with P. plecoglossicida. The investigation into gene expression patterns reveals LcC1qbp's widespread presence, with its highest transcriptional abundance identified in the kidney tissues. Upon infection by P. plecoglossicida, the up-regulation of LcC1qbp in major immune organs manifests at both the transcriptional and translational levels. In the context of RNA interference, transcriptome analysis of C1qbp in HEK 293T cells uncovers 1327 differentially expressed genes (DEGs), featuring 41 significant immune genes. This includes pivotal components such as C1S and C3 of the complement system, along with IL11, IL12RB2, and Myd88, among others. The outcomes of enrichment analysis spotlight the prevalence of DEGs within key pathways like immune system development, myeloid leukocyte-mediated immunity, MAPK signaling, and other immune-related routes. By unveiling the immune response mechanisms of the large yellow croaker to P. plecoglossicida infection, this study bolsters our understanding. Furthermore, it lays the groundwork for pursuing effective strategies in both preventing and treating "visceral white spot disease" in the large yellow croaker.
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Doenças dos Peixes , Perciformes , Infecções por Pseudomonas , Animais , Estudo de Associação Genômica Ampla , Pseudomonas/genética , Imunidade , Perciformes/genética , Proteínas de Peixes/genéticaRESUMO
BACKGROUND: This study aimed to analyze the epidemic characteristics and influencing factors of school influenza outbreaks in Jiangsu Province, China from 2020 to 2023,following the COVID-19 pandemic, to inform prevention and control strategies. METHODS: Data on influenza-like illness(ILI) outbreaks from the Chinese Influenza Surveillance Information System and national-level influenza surveillance sentinel hospitals were analyzed. The temporal distribution, school type, virus strains, and outbreak scales were examined using descriptive statistics. RESULTS: From 2020 to 2023, 1142 influenza outbreaks occurred in schools, with primary schools(ages 6 to 12) accounting for 71.80%. Most large outbreaks were caused by A(H1N1) and A(H3N2), responsible for 8.99% of total outbreaks. Outbreaks were predominantly reported in the pre-peak periods of B(Victoria) and A(H1N1) circulation, accounting for 86.31% and 92.32% of their respective total outbreaks. No concurrent influenza and COVID-19 outbreaks were observed during the study period. CONCLUSION: Primary and secondary schools are high-risk settings for influenza outbreaks. A(H3N2) shows higher adaptability and is more likely to co-circulate with other subtypes/lineages, especially A(H1N1), leading to larger outbreaks. B(Victoria)-caused outbreaks are more frequent but smaller in scale. School influenza outbreaks are more likely to occur during the early stages of seasonal peaks, particularly for B(Victoria) and A(H1N1). This suggests that influenza outbreaks in schools may play a crucial role in seeding and accelerating the spread of the virus within the broader community.
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COVID-19 , Surtos de Doenças , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Influenza Humana , Instituições Acadêmicas , Humanos , China/epidemiologia , Influenza Humana/epidemiologia , Instituições Acadêmicas/estatística & dados numéricos , COVID-19/epidemiologia , Criança , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , SARS-CoV-2 , Pandemias , Adolescente , Vigilância de Evento Sentinela , Feminino , MasculinoRESUMO
Climate warming and atmospheric deposition are altering alpine lake ecosystems at unprecedented rates, whereas their direct and indirect effects on primary consumer communities are unclear. This study presents sedimentary multi-proxy records including chironomids, diatoms, elements and stable isotopes of carbon and nitrogen in 210Pb-dated cores from two alpine lakes located above the timberline in the Taibai Mountain, eastern China. Before â¼2000 CE, chironomid communities were co-dominated by Heterotrissocladius marcidus-type and Micropsectra atrofasciata-type in the two lakes. Thereafter, Tanytarsus glabrescens-type increased rapidly to be a dominant species. Redundancy analyses (RDAs) revealed that chironomid fauna shifts were significantly correlated with rising diatom concentrations in both lakes, declining Ti content in the upstream lake and δ13C depletion in the downstream lake. Although temperature, precipitation and δ15N were not significant explanatory variables in RDAs, climate warming and atmospheric deposition likely promoted terrestrial and aquatic primary production, indicated by synchronous increases in organic matter contents and diatom concentrations in the two sediment cores. Since diatoms contain essential polyunsaturated fatty acids that are essential for chironomids, rising diatom concentrations can promote food quantity and quality. In addition, increased primary production would create organic substrates for chironomid larvae. Recent shifts in chironomid fauna driven by indirect effects of global warming and atmospheric deposition might be a widespread phenomenon in alpine lakes, probably triggering regime shifts in headwater lake ecosystems.
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Chironomidae , Diatomáceas , Animais , Lagos/química , Ecossistema , China , Aquecimento GlobalRESUMO
BACKGROUND: Branchio-oto-renal (BOR) spectrum disorders are linked to pathogenic variants in the EYA1 gene, presenting significant challenges for prenatal ultrasound screening due to their phenotypic variability and complexity. Understanding these disorders' phenotypic expressions and genetic foundations is crucial. METHODS: Our study included pregnant women who underwent fetal whole-exome sequencing at the Department of Medical Genetics and Prenatal Diagnosis, The Third Affiliated Hospital of Zhengzhou University, Henan, China between January 2023 and March 2024. We identified a novel EYA1 gene pathogenic variant and conducted a systematic literature review of all reported prenatal cases associated with EYA1-related diseases, focusing on the detectability of these conditions in prenatal ultrasound. Additionally, we systematically reviewed case reports related to the EYA1 gene, emphasizing missense pathogenic variants for functional predictions and locus position analysis. RESULTS: Our research discovered a new pathogenic variant within the EYA1 gene, highlighting the difficulty of detecting BOR spectrum disorder phenotypes through prenatal ultrasound due to their subtle manifestations. We found that amniotic fluid anomalies and cardiac abnormalities are more prevalent in prenatal cases compared to postnatal cases. A critical region within the EYA Homologous Region (eyaHR) was identified, where missense pathogenic variants significantly affect protein stability, indicating a crucial area associated with the severity of phenotypic expression in EYA1 gene-associated disorders. CONCLUSION: This study enhances the understanding of the genetic landscape of BOR spectrum disorders and suggests that certain phenotypic markers and genetic regions may be pivotal in improving prenatal screening and diagnosis for EYA1-related diseases.
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INTRODUCTION AND HYPOTHESIS: Catheterization is a common treatment for postpartum urinary retention (PUR); however, its application before diagnosis of PUR remains unclear. The aim was to give an overview of the existing literature on the effectiveness and safety of intrapartum or postpartum catheterization in the prevention of PUR. METHODS: This scoping review followed a methodological framework. PubMed, the Cochrane Library, Embase, Web of Science, the China National Knowledge Infrastructure, WanFang, the China Science and Technology Journal Database, and the China Biomedical Literature Database were searched from the inception of each database to 21 May 2023. RESULTS: The search revealed 16 studies examining three different catheterization methodologies, including 12 intrapartum studies. Ten studies concluded that intrapartum or postpartum catheterization prevented PUR, two of which were only for overt or covert PUR. In 4 out of 13 experimental studies, no significant difference was found: one for intrapartum catheterization versus routine nursing, the other for intrapartum or postpartum intermittent versus indwelling catheterization. However, one found that postpartum disposable catheterization after ineffective targeted care reduced the incidence of PUR compared with indwelling catheterization. One out of the 3 case-control studies concluded that prenatal catheterization ≥2 times was a risk factor for PUR. CONCLUSIONS: Based on the findings in this scoping review, catheterization prior to the diagnosis of PUR appears to play a role in preventing PUR and is safe. Preliminary evidence is accumulating on the effectiveness of three types of catheterization methods in preventing PUR, but more comprehensive studies are needed to establish these findings.
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Cateterismo Urinário , Retenção Urinária , Humanos , Feminino , Retenção Urinária/prevenção & controle , Retenção Urinária/etiologia , Retenção Urinária/terapia , Cateterismo Urinário/efeitos adversos , Gravidez , Transtornos Puerperais/prevenção & controle , Transtornos Puerperais/etiologia , Período Pós-PartoRESUMO
Estrogen and estrogen receptor alpha (ERα)-induced gene transcription is tightly associated with ERα-positive breast carcinogenesis. ERα-occupied enhancers, particularly super-enhancers, have been suggested to play a vital role in regulating such transcriptional events. However, the landscape of ERα-occupied super-enhancers (ERSEs) as well as key ERα-induced target genes associated with ERSEs remain to be fully characterized. Here, we defined the landscape of ERSEs in ERα-positive breast cancer cell lines, and demonstrated that bromodomain protein BRD4 is a master regulator of the transcriptional activation of ERSEs and cognate ERα target genes. RET, a member of the tyrosine protein kinase family of proteins, was identified to be a key ERα target gene of BRD4-regulated ERSEs, which, in turn, is vital for ERα-induced gene transcriptional activation and malignant phenotypes through activating the RAS/RAF/MEK2/ERK/p90RSK/ERα phosphorylation cascade. Combination therapy with BRD4 and RET inhibitors exhibited additive effects on suppressing ERα-positive breast cancer both in vitro and in vivo, comparable with that of standard endocrine therapy tamoxifen. Furthermore, combination therapy re-sensitized a tamoxifen-resistant ERα-positive breast cancer cell line to tamoxifen treatment. Taken together, our data uncovered the critical role of a super-enhancer-associated positive feedback loop constituting BRD4/ERα-RET-ERα in ERα-positive breast cancer, and suggested that targeting components in this loop would provide a new therapeutic avenue for treating ERα-positive breast cancer in the clinic.
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Neoplasias da Mama , Receptor alfa de Estrogênio , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios , Retroalimentação Fisiológica , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Proteínas Proto-Oncogênicas c-ret/uso terapêutico , Tamoxifeno/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
BACKGROUND: Traditional total hip arthroplasty (THA) using the direct anterior approach (DAA) requires a hip extension. This study aimed to compare the clinical outcomes of patients undergoing THA with DAA using either the no hip extension (NHE) or the traditional hip extension (THE) strategy. METHODS: A retrospective analysis of demographics, clinical and radiological outcomes, and occurrence of complications was performed using data from 123 patients treated between January 2020 and November 2021. The patients were categorised into two groups: NHE (84 patients) and THE (39 patients). RESULTS: The NHE group exhibited shorter operative time and had more male participants with higher ages. Comparable outcomes were observed in the visual analogue scale, Harris Hip, and Oxford Hip scores at the final follow-up. Furthermore, complications were observed in the NHE and THE groups, including two and one greater trochanteric fractures and three and one transfusions, respectively. CONCLUSIONS: Compared to the THE, employing the NHE strategy during THA with DAA in elderly and young female patients resulted in comparable clinical outcomes with several advantages, such as favourable surgical time. The NHE method also exhibited good safety and effectiveness. Therefore, the NHE strategy may be a favourable option for elderly and young female patients.
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Artroplastia de Quadril , Humanos , Masculino , Feminino , Idoso , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Estudos Retrospectivos , Resultado do Tratamento , Radiografia , Duração da CirurgiaRESUMO
OBJECTIVE: To explore the clinical characteristics and variant of CREBBP gene in a fetus with Rubinstein-Taybi syndrome (RSTS). METHODS: A fetus with RSTS diagnosed at the Third Affiliated Hospital of Zhengzhou University in August 2022 was selected as the study subject. Clinical data, amniotic fluid sample of the fetus and peripheral blood samples of its parents were collected for whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing. RESULTS: Foot malformation, cerebellar vermis agenesis, brain agenesis, polysyndactyly of the big toes and other phenotypes were found by prenatal ultrasound. WES revealed that the fetus has harbored a heterozygous c.4684G>T (p.E1562*) variant in exon 28 of the CREBBP gene (NM_004380.3), which was de novo in origin. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was predicted to be pathogenic (PVS1+PS2_Moderate+PM2_Supporting). After genetic counseling, the couple had opted to terminate the pregnancy and refused autopsy of the fetus. CONCLUSION: The c.4684G>T (p.E1562*) variant of the CREBBP gene probably underlay the RSTS in this fetus. The newly discovered variant has enriched the mutational spectrum of the CREBBP gene and illustrated that WES is an efficient tool for the prenatal diagnosis of RSTS.
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Proteína de Ligação a CREB , Sequenciamento do Exoma , Diagnóstico Pré-Natal , Síndrome de Rubinstein-Taybi , Humanos , Síndrome de Rubinstein-Taybi/genética , Feminino , Gravidez , Proteína de Ligação a CREB/genética , Adulto , Feto/anormalidades , Feto/diagnóstico por imagem , Mutação , Masculino , Ultrassonografia Pré-NatalRESUMO
Chinese patent medicine constitutes a vital segment of the traditional Chinese medicine(TCM) industry and stands as a significant emblem of TCM modernization. At present, the quality stability between batches of Chinese patent medicine preparations has become a pivotal factor directly restricting the high-quality development of the TCM industry. Consequently, addressing the homogeneity of Chinese patent medicines, this paper proposes a research scheme of homogenization feeding. It systematically elaborates on the object and pretreatment of homogenization, operational procedures of homogenization feeding, selection of homogenization evaluation indices, homogenization feeding algorithm, and homogenization feeding process. With the key quality control indicators as the homogenization target, the homogenization feeding process and its quality analysis were discussed. Finally, a demonstration strategy for homogenization feeding of Chinese patent medicine was formed, providing the scientific basis for advancing the research of quality consistency across batches of Chinese patent medicine preparations.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Controle de Qualidade , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/normas , Medicamentos sem Prescrição/química , Composição de Medicamentos/métodosRESUMO
The substituted benzene derivatives are essential to organic synthesis, medicinal chemistry, and material science. However, the 1,3-di- and 1,3,5-trisubstituted benzenes are far less prevalent in small-molecule drugs than other substitution patterns, likely due to the lack of robust, efficient, and convenient synthetic methods. Here, we report a Mo-catalyzed intermolecular deoxygenative benzene-forming reaction of readily available ynones and allylic amines. A wide range of unsymmetric and unfunctionalized 1,3-di- and 1,3,5-trisubstituted benzenes were obtained in up to 88% yield by using a commercially available molybdenum catalyst. The synthetic potential of the method was further illustrated by synthetic transformations, a scale-up synthesis, and derivatization of bioactive molecules. Preliminary mechanistic studies suggested that this benzene-forming process might proceed through a Mo-catalyzed aza-Michael addition/[1,5]-hydride shift/cyclization/aromatization cascade. This strategy not only provided a facile, robust, and modular approach to various meta-substituted benzene derivatives but also demonstrated the potential of molybdenum catalysis in the challenging intermolecular deoxygenative cross-coupling reactions.
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The catalytic asymmetric cyclopropanation reaction of alkenes with diazo compounds is a direct and powerful method to construct chiral cyclopropanes that are essential to drug discovery. However, diazo compounds are potentially explosive and often require hazardous reagents for their preparation. Here, we report on the use of 1,2-dicarbonyl compounds as safe and readily available surrogates for diazo compounds in the direct catalytic asymmetric deoxygenative cyclopropanation reaction. Enabled by a class of simple and readily accessible chiral salen-Mo catalysts, the reaction proceeded with generally good enantioselectivities and yields toward a wide range of substrates (80 examples). Preliminary mechanistic studies suggested that the proposed µ-oxo bridged dinuclear Mo(III)-species was the catalytically active species. This strategy not only provides a promising route for the synthesis of chiral cyclopropanes but also opens a new window for the potential applications of chiral salen-Mo complexes in asymmetric catalysis.
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BACKGROUND: Previous studies have shown that monotherapy with apatinib, an oral tyrosine kinase inhibitor, has promising efficacy for treating recurrent or metastatic (RM) nasopharyngeal carcinoma (NPC) patients. In this study, we aimed to assess the efficacy and safety of apatinib combined with capecitabine as a second-line therapy or beyond for treating RM-NPC patients who failed the first-line platinum-based chemotherapy. METHODS: In this single-arm, phase II study, we enrolled RM-NPC patients who had at least one measurable lesion according to the Response Evaluation Criteria in Solid Tumors (RECIST v1.1). The sample size was determined using Simon's two-stage design. All patients were administered with apatinib 500 mg once daily and capecitabine 1000 mg/m2 twice per day on days 1-14 of each 21-day cycle. The primary endpoint was the objective response rate (ORR), and the secondary endpoints comprised disease control rate (DCR), duration of response (DoR), progression-free survival (PFS), overall survival (OS), and safety. RESULTS: We enrolled 64 patients from September 2018 to August 2020. The ORR and DCR were 39.1% (95% CI, 27.1-52.1) and 85.9% (95% CI, 75.0-93.4), respectively. The median DoR was 14.4 months (95% CI, 7.8-21.0). As of April 20, 2021, the median follow-up duration was 12.0 months. The median PFS was 7.5 months (95% CI, 5.0-10.0) and the median OS was 15.7 months (95% CI, 11.3-20.1). The most common toxicities of any grade were anemia (75.0%), hand-foot syndrome (65.6%), and proteinuria (64.0%). Grade 3-4 toxicities were observed in 36 (56.3%) patients, with hypertension (14.1%), mucositis (12.4%), and fatigue (10.9%) most commonly observed. CONCLUSIONS: Apatinib plus capecitabine shows promising efficacy as a second-line treatment option in pretreated platinum-refractory RM-NPC patients. Dose selection of this combination needs further investigation considering the toxicity. TRIAL REGISTRATION: Chi-CTR1800017229.