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Characterizing somatic mutations in the brain is important for disentangling the complex mechanisms of aging, yet little is known about mutational patterns in different brain cell types. Here, we performed whole-genome sequencing (WGS) of 86 single oligodendrocytes, 20 mixed glia, and 56 single neurons from neurotypical individuals spanning 0.4-104 years of age and identified >92,000 somatic single-nucleotide variants (sSNVs) and small insertions/deletions (indels). Although both cell types accumulate somatic mutations linearly with age, oligodendrocytes accumulated sSNVs 81% faster than neurons and indels 28% slower than neurons. Correlation of mutations with single-nucleus RNA profiles and chromatin accessibility from the same brains revealed that oligodendrocyte mutations are enriched in inactive genomic regions and are distributed across the genome similarly to mutations in brain cancers. In contrast, neuronal mutations are enriched in open, transcriptionally active chromatin. These stark differences suggest an assortment of active mutagenic processes in oligodendrocytes and neurons.
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Envelhecimento , Encéfalo , Neurônios , Oligodendroglia , Humanos , Envelhecimento/genética , Envelhecimento/patologia , Cromatina/genética , Cromatina/metabolismo , Mutação , Neurônios/metabolismo , Neurônios/patologia , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Análise da Expressão Gênica de Célula Única , Sequenciamento Completo do Genoma , Encéfalo/metabolismo , Encéfalo/patologia , Polimorfismo de Nucleotídeo Único , Mutação INDEL , Bancos de Espécimes Biológicos , Células Precursoras de Oligodendrócitos/metabolismo , Células Precursoras de Oligodendrócitos/patologiaRESUMO
Focal copy-number amplification is an oncogenic event. Although recent studies have revealed the complex structure1-3 and the evolutionary trajectories4 of oncogene amplicons, their origin remains poorly understood. Here we show that focal amplifications in breast cancer frequently derive from a mechanism-which we term translocation-bridge amplification-involving inter-chromosomal translocations that lead to dicentric chromosome bridge formation and breakage. In 780 breast cancer genomes, we observe that focal amplifications are frequently connected to each other by inter-chromosomal translocations at their boundaries. Subsequent analysis indicates the following model: the oncogene neighbourhood is translocated in G1 creating a dicentric chromosome, the dicentric chromosome is replicated, and as dicentric sister chromosomes segregate during mitosis, a chromosome bridge is formed and then broken, with fragments often being circularized in extrachromosomal DNAs. This model explains the amplifications of key oncogenes, including ERBB2 and CCND1. Recurrent amplification boundaries and rearrangement hotspots correlate with oestrogen receptor binding in breast cancer cells. Experimentally, oestrogen treatment induces DNA double-strand breaks in the oestrogen receptor target regions that are repaired by translocations, suggesting a role of oestrogen in generating the initial translocations. A pan-cancer analysis reveals tissue-specific biases in mechanisms initiating focal amplifications, with the breakage-fusion-bridge cycle prevalent in some and the translocation-bridge amplification in others, probably owing to the different timing of DNA break repair. Our results identify a common mode of oncogene amplification and propose oestrogen as its mechanistic origin in breast cancer.
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Neoplasias da Mama , Receptor alfa de Estrogênio , Amplificação de Genes , Oncogenes , Translocação Genética , Feminino , Humanos , Neoplasias da Mama/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios/metabolismo , Oncogenes/genética , Translocação Genética/genética , Genoma Humano/genética , Quebras de DNA de Cadeia Dupla , Especificidade de ÓrgãosRESUMO
SINE-VNTR-Alu (SVA) retrotransposons are evolutionarily young and still-active transposable elements (TEs) in the human genome. Several pathogenic SVA insertions have been identified that directly mutate host genes to cause neurodegenerative and other types of diseases. However, due to their sequence heterogeneity and complex structures as well as limitations in sequencing techniques and analysis, SVA insertions have been less well studied compared to other mobile element insertions. Here, we identified polymorphic SVA insertions from 3646 whole-genome sequencing (WGS) samples of >150 diverse populations and constructed a polymorphic SVA insertion reference catalog. Using 20 long-read samples, we also assembled reference and polymorphic SVA sequences and characterized the internal hexamer/variable-number-tandem-repeat (VNTR) expansions as well as differing SVA activity for SVA subfamilies and human populations. In addition, we developed a module to annotate both reference and polymorphic SVA copies. By characterizing the landscape of both reference and polymorphic SVA retrotransposons, our study enables more accurate genotyping of these elements and facilitate the discovery of pathogenic SVA insertions.
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Genoma Humano , Retroelementos , Humanos , Elementos Alu , Genoma Humano/genética , Repetições Minissatélites/genética , Retroelementos/genética , Elementos Nucleotídeos Curtos e DispersosRESUMO
Lysophosphatidic acid acyltransferases (LPAATs) catalyze the formation of phosphatidic acid (PA), a central metabolite in both prokaryotic and eukaryotic organisms for glycerolipid biosynthesis. Phaeodactylum tricornutum contains at least two plastid-localized LPAATs (ptATS2a and ptATS2b), but their roles in lipid synthesis remain unknown. Both ptATS2a and ptATS2b could complement the high temperature sensitivity of the bacterial plsC mutant deficient in LPAAT. In vitro enzyme assays showed that they prefer lysophosphatidic acid over other lysophospholipids. ptATS2a is localized in the plastid inner envelope membrane and CRISPR/Cas9-generated ptATS2a mutants showed compromised cell growth, significantly changed plastid and extra-plastidial membrane lipids at nitrogen-replete condition and reduced triacylglycerols (TAGs) under nitrogen-depleted condition. ptATS2b is localized in thylakoid membranes and its knockout led to reduced growth rate and TAG content but slightly altered molecular composition of membrane lipids. The changes in glycerolipid profiles are consistent with the role of both LPAATs in the sn-2 acylation of sn-1-acyl-glycerol-3-phosphate substrates harboring 20:5 at the sn-1 position. Our findings suggest that both LPAATs are important for membrane lipids and TAG biosynthesis in P. tricornutum and further highlight that 20:5-Lyso-PA is likely involved in the massive import of 20:5 back to the plastid to feed plastid glycerolipid syntheses.
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Aciltransferases , Lipídeos de Membrana , Triglicerídeos , Aciltransferases/metabolismo , Plastídeos/metabolismo , Ácidos Fosfatídicos , NitrogênioRESUMO
BACKGROUND: The objective of this study was to determine the short-term and long-term effects of a nutrition intervention in using 37 years of follow-up data. METHODS: The Linxian Dysplasia Population Nutrition Intervention Trial was a randomized, double-blind, placebo-controlled trial with 7 years of intervention and 30 years of follow-up. The Cox proportional hazard model was used for analyses. Subgroup analyses were conducted in age and sex subgroups, and the 30 years of follow-up were divided into two 15-year early and late periods. RESULTS: The results at 37 years did not indicate any effects on mortality from cancers or other diseases. In the first 15 years, the intervention decreased the overall risk of gastric cancer deaths in all participants (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.58-1.00) and in the subgroup participants younger than 55 years (HR, 0.64; 95% CI, 0.43-0.96). In addition, in the group younger than 55 years (HR, 0.58; 95% CI, 0.35-0.96), the intervention decreased the risk of death from other diseases; and, in the group aged 55 years and older (HR, 0.75; 95% CI, 0.58-0.98), the intervention reduced the risk of death from heart disease. There were no significant results in the later 15 years, which indicated the disappearance of the intervention effect. Comparing demographic characteristics between those who died during the two periods, the participants who died later included more women, had a higher education level, had a lower smoking rate, were younger, and also more had a mild degree of esophageal dysplasia, representing a better lifestyle and health condition. CONCLUSIONS: Long-term follow-up indicated no effect of nutrition on deaths in a population with esophageal squamous dysplasia, further supporting the significance of continuous nutritional intervention for cancer protection. The pattern of protective effect of a nutrition intervention on gastric cancer in patients with esophageal squamous dysplasia was similar to that in the general population. Participants who died in the later period had more protective factors than those who died in the earlier period, contributing to the obvious effect of the intervention in early stage disease.
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Carcinoma de Células Escamosas , Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Feminino , Estudos de Coortes , Neoplasias Gástricas/epidemiologia , Estado Nutricional , Neoplasias Esofágicas/epidemiologia , HiperplasiaRESUMO
Brain death (BD) donors are the primary source of donor organs for liver transplantation. However, the effects of BD on donor livers and outcomes after liver transplantation remain unclear. Here, we explored the role of complement and the therapeutic effect of complement inhibition in BD-induced liver injury and posttransplantation injury in a mouse BD and liver transplantation model. For complement inhibition, we used complement receptor 2 (CR2)-Crry, a murine inhibitor of C3 activation that specifically targets sites of complement activation. In the mouse model, BD resulted in complement activation and liver injury in donor livers and a cascade liver injury posttransplantation, mediated in part through the C3a-C3aR (C3a receptor) signaling pathway, which was ameliorated by treatment with CR2-Crry. Treatment of BD donors with CR2-Crry improved graft survival, which was further improved when recipients received an additional dose of CR2-Crry posttransplantation. Mechanistically, we determined that complement inhibition alleviated BD-induced donor liver injury and posttransplant cascade injury by regulating phosphoinositide 3-kinase (PI3K) signaling pathways. Together, BD induced donor liver injury and cascade injury post-transplantation, which was mediated by complement activation products acting on PI3K signaling pathways. Our study provides an experimental basis for developing strategies to improve the survival of BD donor grafts in liver transplantation.
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Doença Hepática Crônica Induzida por Substâncias e Drogas , Transplante de Fígado , Traumatismo por Reperfusão , Animais , Camundongos , Humanos , Fosfatidilinositol 3-Quinases , Fosfatidilinositol 3-Quinase , Transplante de Fígado/efeitos adversos , Morte Encefálica , Doadores Vivos , Proteínas do Sistema Complemento , Transdução de Sinais , Proteínas Recombinantes de FusãoRESUMO
In brief: Impaired spermatogenesis resulting from disturbed cholesterol metabolism due to intake of high-fat diet (HFD) has been widely recognized, however, the role of preprotein invertase subtilin 9 (PCSK9), which is a negative regulator of cholesterol metabolism, has never been reported. This study aims to reveal the role of PCSK9 on spermatogenesis induced by HFD in mice. Abstract: Long-term consumption of a high-fat diet (HFD) is an important factor that leads to impaired spermatogenesis exhibiting poor sperm quantity and quality. However, the mechanism of this is yet to be elucidated. Disrupted cholesterol homeostasis is one of many crucial pathological factors which could contribute to impaired spermatogenesis. As a negative regulator of cholesterol metabolism, preprotein invertase subtilin 9 (PCSK9) mediates low density lipoprotein receptor (LDLR) degradation to the lysosome, thereby reducing the expression of LDLR on the cell membrane and increasing serum low-density lipoprotein cholesterol level, resulting in lipid metabolism disorders. Here, we aim to study whether PCSK9 is a pathological factor for impaired spermatogenesis induced by HFD and the underlying mechanism. To meet the purpose of our study, we utilized wild-type C57BL/6 male mice and PCSK9 knockout mice with same background as experimental subjects and alirocumab, a PCSK9 inhibitor, was used for treatment. Results indicated that HFD induced higher PCSK9 expression in serum, liver, and testes, and serum PCSK9 is negatively correlated with spermatogenesis, while both PCSK9 inhibitor treatment and PCSK9 knockout methodologies ameliorated impaired lipid metabolism and spermatogenesis in mice fed a HFD. This could be due to the overexpression of PCSK9 induced by HFD leading to dyslipidemia, resulting in testicular lipotoxicity, thus activating the Bcl-2-Bax-Caspase3 apoptosis signaling pathway in testes, particularly in Leydig cells. Our study demonstrates that PCSK9 is an important pathological factor in the dysfunction of spermatogenesis in mice induced by HFD. This finding could provide innovative ideas for the diagnosis and treatment of male infertility.
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Dieta Hiperlipídica , Pró-Proteína Convertase 9 , Animais , Masculino , Camundongos , beta-Frutofuranosidase , Colesterol , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pró-Proteína Convertase 9/genética , SêmenRESUMO
BACKGROUND: This study aimed to explore the association between drinking water source and risk of upper gastrointestinal (UGI) cancer, including esophageal cancer (EC) and gastric cancer (GC), in the Linxian General Population Nutrition Intervention Trial (NIT) cohort. METHODS: In this study, we used data from the Linxian NIT cohort, which included 29,584 healthy adults aged 40 to 69 years. Subjects were enrolled in April 1986 and followed up until March 2016. Tap water drinking status and demographic characteristics were collected at baseline. Subjects who drank tap water were treated as the exposed group. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated using the Cox proportional hazard model. RESULTS: A total of 5,463 cases of UGI cancer were identified during the 30-year follow-up period. After adjusting for multiple factors, the incidence rate of UGI cancer in participants who drank tap water was significantly lower compared with individuals in the control (HR = 0.91, 95% CI: 0.86-0.97). A similar association was observed between tap water drinking and EC incidence (HR = 0.89, 95% CI: 0.82-0.97). The association between drinking tap water and risk of UGI cancer and EC incidence did not vary across the subgroup by age and gender (All Pinteraction > 0.05). For EC incidence, an interaction effect was observed for riboflavin/niacin supplements and drinking water source (Pinteraction = 0.03). No association was observed between drinking water source and GC incidence. CONCLUSIONS: In this prospective cohort study in Linxian, participants who drank tap water had a lower risk of EC incidence. As a source of drinking water, use of tap water may reduce the risk of EC by avoiding exposure to nitrate/nitrite. Measures should be taken to improve the quality of drinking water in high-incidence areas of EC. TRIAL REGISTRATION: The trial is registered with ClinicalTrials.gov (NCT00342654, 21/06/2006), and the trial name is Nutrition Intervention Trials in Linxian Follow-up Study.
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Água Potável , Neoplasias Esofágicas , Neoplasias Gástricas , Adulto , Humanos , Incidência , Seguimentos , Água Potável/efeitos adversos , Estudos Prospectivos , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/etiologia , Neoplasias Esofágicas/epidemiologia , China/epidemiologia , Fatores de RiscoRESUMO
Photocatalytic oxidation is a popular transformation way for organic synthesis and is widely applied in academia and industry. Herein, we report a blue light-induced alkylation-oxidation tandem reaction for the synthesis of diverse ketones by combining alkyl radical addition and oxidation of alkenyl borates. This reaction shows excellent functional group compatibility in acceptable yields, and diversity of radical precursors is applicable.
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BACKGROUND: The National Comprehensive Cancer Network guidelines recommend routine postoperative adjuvant radiotherapy and chemotherapy for patients with stage III rectal cancer who do not receive neoadjuvant therapy before surgery. The present study aimed to evaluate the value of postoperative radiotherapy in patients with low-risk disease (pT1-3N1M0) who did not receive neoadjuvant therapy prior to total mesorectal excision. METHODS: We used the Surveillance, Epidemiology, and End Results database (2004-2016) to retrospectively recruit patients with pT1-3N1M0 rectal cancer whose initial treatment was radical surgery with postoperative adjuvant chemotherapy. A propensity score model was used to balance the baseline covariates. RESULTS: Of the 2012 patients included in the present study, 1384 received adjuvant chemoradiotherapy (radio group), whereas the remaining 718 received chemotherapy alone (no-radio group). There was no significant difference in cancer-specific survival rate between the two groups (log-rank test χ2 = 2.372, P = 0.124) in the overall sample. Additionally, in the propensity score-matched cohort, adjuvant radiotherapy did not improve cancer-specific survival. Subgroup analysis showed that having three positive lymph nodes and a tumor > 50 mm, combined with postoperative adjuvant chemotherapy, could lead to an improved tumor-specific survival rate, while other cases did not benefit from postoperative radiotherapy. CONCLUSIONS: For patients with pT1-3N1M0 rectal cancer who did not receive neoadjuvant therapy before surgery, postoperative radiotherapy in addition to adjuvant chemotherapy did not significantly improve survival rates. The number of positive nodes (n = 3) and tumor size (> 50 mm) were found to be potential screening indicators for postoperative adjuvant radiotherapy.
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Neoplasias Retais , Humanos , Estudos Retrospectivos , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia , Quimioterapia Adjuvante/métodos , Quimiorradioterapia Adjuvante , Terapia Neoadjuvante/métodos , Estadiamento de Neoplasias , Resultado do TratamentoRESUMO
The present study aimed to investigate the effect of Apelin-13 on nicotine-induced injuries of cardiomyocytes. To establish an H9c2 cell model of nicotine-induced apoptosis, H9c2 cells were divided into the control group, nicotine group, and Apelin-13+nicotine group. The apoptosis rate of H9c2 cells was then detected by flow cytometry. Later, the expressions of indicators related to apoptosis, oxidative stress, and inflammatory responses were measured via Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR). The results revealed that the expression of B-cell lymphoma-2 (Bcl-2) was remarkably down-regulated (P<0.01), while the apoptosis rate and the expressions of apoptosis-related proteins (Bcl-2-associated X protein (Bax) and cysteinyl aspartate specific proteinase-3 (Caspase-3)) were significantly up-regulated (P<0.01) in the nicotine group. However, the variation trends of Bcl-2, Bax, and Caspase-3 in the Apelin-13+nicotine group were contrary to those in the nicotine group (P<0.01). Additionally, the expressions of interleukin-1 beta (IL-1ß) and tumor necrosis factor-alpha (TNF-α) obviously declined (P<0.01), while those of superoxide dismutase 1 (SOD1) and SOD2 dramatically rose in the Apelin-13+nicotine group (P<0.01). Furthermore, Apelin-13 treatment evidently elevated the expressions of phosphorylated protein kinase B (p-AKT) and phosphorylated phosphatidylinositol 3-kinase (PI3K). In conclusion, Apelin-13 inhibits nicotine-induced apoptosis and oxidative stress in H9c2 cells via the PI3K/AKT signaling pathway.
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Miócitos Cardíacos , Proteínas Proto-Oncogênicas c-akt , Caspase 3 , Ligantes , Nicotina/farmacologia , Fosfatidilinositol 3-Quinases , Proteína X Associada a bcl-2 , Apoptose , Estresse OxidativoRESUMO
This paper considers the problem of estimating the parameters of a frequency-hopping signal under non-cooperative conditions. To make the estimation of different parameters independently of each other, a compressed domain frequency-hopping signal parameter estimation algorithm based on the improved atomic dictionary is proposed. By segmenting and compressive sampling the received signal, the center frequency of each signal segment is estimated using the maximum dot product. The signal segments are processed with central frequency variation using the improved atomic dictionary to accurately estimate the hopping time. We highlight that one superiority of the proposed algorithm is that high-resolution center frequency estimation can be directly obtained without reconstructing the frequency-hopping signal. Additionally, another superiority of the proposed algorithm is that hopping time estimation has nothing to do with center frequency estimation. Numerical results show that the proposed algorithm can achieve superior performance compared with the competing method.
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Algoritmos , Compressão de DadosRESUMO
OBJECTIVE: In order to exploring Erectile Dysfunction(ED) syndrome and syndrome differentiation based on latent structure to provide objective evidence to support Traditional Chinese Medicine(TCM) dialectic. METHODS: Cases and clinical experience in the treatment of erectile dysfunction in Chinese medicine in CNKI, Wanfang Database, cqVIP Database, were searched. Time from the database construction to January, 2023. Extraction and specification of symptom data with reference to national standards. Lantern 5.0 software was used to make the latent structure of the data based on LTM-EAST method. Latent probability, conditional probability, information coverage, mutual information and other data were combined to manually interpret the model and perform clustering analysis on the latent classes to analyze the symptomatic features and clinical evidence of erectile dysfunction and establish the rules of identification. RESULT: A total of 361 cases of erectile dysfunction were included, 21 latent variables were constructed, 9 comprehensive clustering models and 13 discriminative rules were established. The pathological factors of the obtained erectile dysfunction are dampness, heat, yin deficiency, blood stasis, spleen deficiency, kidney deficiency, liver depression, and qi stagnation. The certificate types are stasis of blood, liver qi stagnation, damp-heat entrapment (dampness is heavy, heat is heavy, damp-heat is heavy), yin deficiency (yin deficiency with heat, kidney yin deficiency), vital fire failure, qi deficiency (qi deficiency with heat, kidney qi deficiency), heart and spleen deficiency, panic injury to kidney, spleen and kidney deficiency. CONCLUSION: The common types of erectile dysfunction obtained are generally consistent with existing guidelines, but more subcategories exist in the certificate type. The presence of symptoms that cannot be well matched in some of the certificate types is presumed to be due to the complex pathogenesis of erectile dysfunction common compound evidence, many evidence models are seen in the main symptoms of liver qi stagnation evidence pulse strings, suggesting that clinical treatment should pay attention to the regulation of emotional and moral, to ease the patient's emotions. The corresponding dialectical rules can quantify the dialectical criteria and provide an objective basis for non-TCM professionals to clinically determine the TCM evidence type of patients.
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Disfunção Erétil , Deficiência da Energia Yin , Masculino , Humanos , Deficiência da Energia Yin/diagnóstico , Disfunção Erétil/diagnóstico , Medicina Tradicional Chinesa/métodos , SíndromeRESUMO
We reveal here the construction of Ni-based metal-organic frameworks (MOFs) and conjugated coordination polymers (CCPs) with different structural dimensionalities, including closely π-stacked 1D chains (Ni-1D), aggregated 2D layers (Ni-2D), and a 3D framework (Ni-3D), based on 2,3,5,6-tetraamino-1,4-hydroquinone (TAHQ) and its various oxidized forms. These materials have the same metal-ligand composition but exhibit distinct electronic properties caused by different dimensionalities and supramolecular interactions between SBUs, ligands, and structural motifs. The electrical conductivity of these materials spans nearly 8 orders of magnitude, approaching 0.3 S/cm.
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Here we report a copper-catalyzed formal dehydration polymerization of propargylic alcohols. Copper catalysis allows for efficient in situ generation of [n]cumulenes (n = 3, 5) by a soft deprotonation/ß-elimination pathway and subsequent polymerization via organocopper species. Alkyne polymers (Mn up to 36.2 kg/mol) were produced with high efficiency (up to 95% yield) and excellent functional group tolerance. One-pot synthesis of semiconducting head-to-head poly(phenylacetylene) was demonstrated through a polymerization-isomerization sequence.
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Cobre , Desidratação , Alcinos , Catálise , Humanos , Polienos , PolimerizaçãoRESUMO
Recent advancements in quantum sensing have sparked transformative detection technologies with high sensitivity, precision, and spatial resolution. Owing to their atomic-level tunability, molecular qubits and ensembles thereof are promising candidates for sensing chemical analytes. Here, we show quantum sensing of lithium ions in solution at room temperature with an ensemble of organic radicals integrated in a microporous metal-organic framework (MOF). The organic radicals exhibit electron spin coherence and microwave addressability at room temperature, thus behaving as qubits. The high surface area of the MOF promotes accessibility of the guest analytes to the organic qubits, enabling unambiguous identification of lithium ions and quantitative measurement of their concentration through relaxometric and hyperfine spectroscopic methods based on electron paramagnetic resonance (EPR) spectroscopy. The sensing principle presented in this work is applicable to other metal ions with nonzero nuclear spin.
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Here, we describe the unexpected discovery of a Cu-catalyzed condensation polymerization reaction of propargylic electrophiles (CPPE) that transforms simple C3 building blocks into polydiynes of C6 repeating units. This reaction was achieved by a simple system composed of a copper acetylide initiator and an electron-rich phosphine ligand. Alkyne polymers (up to 33.8 kg/mol) were produced in good yields and exclusive regioselectivity with high functional group compatibility. Hydrogenation of the product afforded a new polyolefin-type backbone, while base-mediated isomerization led to a new type of dienyne-based electron-deficient conjugated polymer. Mechanistic studies revealed a new α-α selective Cu-catalyzed dimerization pathway of the C3 unit, followed by in situ organocopper-mediated chain-growth propagation. These insights not only provide an important understanding of the Cu-catalyzed CPPE of C3, C4, and C6 monomers in general but also lead to a significantly improved synthesis of polydiynes from simpler starting materials with handles for the incorporation of an α-end functional group.
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Alcinos , Cobre , Catálise , Dimerização , Polimerização , PolímerosRESUMO
We aimed to explore the association of combined risk factors with risk of death from upper gastrointestinal (UGI) cancer, including esophageal squamous cell carcinoma (ESCC), gastric cardia carcinoma (GCC) and gastric noncardia carcinoma (GNCC) in the Linxian Nutrition Intervention Trial (NIT) cohort. The NIT cohort included 29 584 healthy adults. A combined risk score (CRS) was calculated using a point system method based on 10 risk factors collected at baseline, including gender, smoking, alcohol drinking, body mass index, family history of UGI cancer, drinking tap water, tooth loss and consumption of fresh fruit, eggs and meat. Possible score ranged from 0 to 31, and higher score indicated as poorer health status. Subjects were divided into three groups by the CRS (<12 points, 12 to 20 points and >20 points). The group of CRS <12 points was considered as the reference. During the 30-year follow-up, we identified 4553 UGI cancer deaths. Compared to subjects with a CRS <12 points, the adjusted HRs for CRS of 12 to 20 points and >20 points were 1.69 (95% CI: 1.56-1.83) and 3.06 (95% CI: 2.82-3.33) for UGI cancer mortality, respectively (Ptrend < .001). Comparable associations were also observed for ESCC, GCC and GNCC mortality. Results remained similar across different age groups (Pinteraction > .05). All HRs observed in the second half follow-up period were stronger than that observed in the first half follow-up period. Our study indicated that higher CRS was associated with increased risk of UGI cancer mortality. Appropriate measures should be taken to reduce unhealthy lifestyles.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Neoplasias Gastrointestinais , Neoplasias Gástricas , Adulto , China/epidemiologia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/epidemiologia , Neoplasias Gastrointestinais/epidemiologia , Humanos , Estudos Prospectivos , Fatores de Risco , Neoplasias Gástricas/patologiaRESUMO
BACKGROUND: The objective of this study was to update the association between multivitamin supplementation and total or cause-specific mortality in a population with a high prevalence of undernutrition in China. METHODS: The Linxian Dysplasia Nutrition Intervention Trial was a randomized, double-blind, placebo-controlled trial in which 3318 persons aged 40-69 years with esophageal squamous dysplasia were assigned to receive daily multivitamin supplementation or a placebo for 6 years and were followed for 29 years. The primary outcome was esophageal/gastric cardia cancer mortality. The data were analyzed with Cox proportional hazards regression models. Subgroup analyses were performed by common characteristics such as age and gender. RESULTS: The cumulative total mortality was 83.5%. Multivitamin supplementation did not affect total or cause-specific mortality in the participants as a whole (hazard ratio [HR], 0.96; 95% confidence interval [CI], 0.89-1.03). Subgroup analyses showed that no association between multivitamin supplementation and all-cause mortality was observed in men (HR, 0.90; 95% CI, 0.81-1.01), women (HR, 1.01; 95% CI, 0.91-1.12), younger participants (HR, 0.97; 95% CI, 0.87-1.08), or older participants (HR, 0.94; 95% CI, 0.85-1.04). Significant reductions in heart disease mortality (HR, 0.64; 95% CI, 0.47-0.87) and cerebrovascular disease mortality (HR, 0.74; 95% CI, 0.56-1.00) were seen in older men. In a subgroup of younger men and a subgroup of moderate or severe dysplasia, subjects receiving multivitamin supplementation had a lower risk of esophageal/cardia cancer mortality (HR for younger men, 0.76; 95% CI, 0.58-0.99; HR for moderate or severe dysplasia, 0.76; 95% CI, 0.58-1.00). No association between multivitamin supplementation and any cause-specific mortality was observed in a mild dysplasia population. CONCLUSIONS: Multivitamin supplementation in a population with esophageal squamous dysplasia was not associated with the risk of total mortality in the 35-year follow-up of this randomized controlled trial. In light of this and previous trials, multivitamin supplements should be used thoughtfully to improve health status of populations with esophageal squamous dysplasia. LAY SUMMARY: Multivitamin supplementation is common, yet its effect on mortality is unclear. The aim of this study was to update the long-term effects of multivitamin supplementation on total and cause-specific mortality during nearly 35 years of follow-up in the Linxian Dysplasia Nutrition Intervention Trial in China. Multivitamin supplementation in a population with esophageal squamous dysplasia was not associated with the risk of total mortality in the 35-year follow-up of this randomized controlled trial, and this indicates that multivitamin supplements should be used thoughtfully to improve health status.
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Carcinoma de Células Escamosas , Neoplasias Esofágicas , Idoso , Carcinoma de Células Escamosas/tratamento farmacológico , Suplementos Nutricionais , Neoplasias Esofágicas/epidemiologia , Feminino , Seguimentos , Humanos , Hiperplasia , Masculino , Vitaminas/uso terapêuticoRESUMO
Electrically conducting 2D metal-organic frameworks (MOFs) have attracted considerable interest, as their hexagonal 2D lattices mimic graphite and other 2D van der Waals stacked materials. However, understanding their intrinsic properties remains a challenge because their crystals are too small or of too poor quality for crystal structure determination. Here, we report atomically precise structures of a family of 2D π-conjugated MOFs derived from large single crystals of sizes up to 200 µm, allowing atomic-resolution analysis by a battery of high-resolution diffraction techniques. A designed ligand core rebalances the in-plane and out-of-plane interactions that define anisotropic crystal growth. We report two crystal structure types exhibiting analogous 2D honeycomb-like sheets but distinct packing modes and pore contents. Single-crystal electrical transport measurements distinctively demonstrate anisotropic transport normal and parallel to the π-conjugated sheets, revealing a clear correlation between absolute conductivity and the nature of the metal cation and 2D sheet packing motif.