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1.
Angew Chem Int Ed Engl ; 63(6): e202318344, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38126567

RESUMO

Sulfilimines, the aza-variants of sulfoxides, are key structural motifs in natural products, pharmaceuticals, and agrochemicals; and sulfilimine synthesis is therefore important in organic chemistry. However, methods for radical sulfilimination remain elusive, and as a result, the structural diversity of currently available sulfilimines is limited. Herein, we report the first protocol for decarboxylative radical sulfilimination reactions between sulfenamides and N-hydroxyphthalimide esters of primary, secondary, and tertiary alkyl carboxylic acids, which were achieved via a combination of photoredox, copper, and Brønsted base catalysis. This novel protocol provided a wide variety of sulfilimines, in addition to serving as an efficient route for the synthesis of S-alkyl/S-aryl homocysteine sulfilimines and S-(4-methylphenyl) homocysteine sulfoximine. Moreover, it could be used for late-stage introduction of a sulfilimine group into structurally complex molecules, thereby avoiding the need to preserve labile organosulfur moieties through multistep synthetic sequences. A mechanism involving photocatalytic substrate transformation and copper-mediated C(sp3 )-S bond formation is proposed.

2.
J Stroke Cerebrovasc Dis ; 32(10): 107311, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37659193

RESUMO

OBJECTIVES: This study aimed to investigate the potential correlations among serum 25-hydroxyvitamin D [25(OH)D] levels, white matter hyperintensity (WMH) and cognitive function in patients with non-disabling ischemic cerebrovascular events (NICE). METHODS: This was a prospective investigation of 160 NICE patients with age of 40 years or older. Cognitive function was evaluated by the Montreal Cognitive Assessment (MoCA). White matter lesions were evaluated by WMH using Fazekas scores. Spearman correlation analysis and linear regression models were used to identify the associations between serum 25(OH)D levels and cognitive function. Binary logistic regression analysis models were used to evaluate the predictable value of serum 25(OH)D levels and WMH for cognitive impairment. RESULTS: Patients with inadequate 25(OH)D levels had lower MoCA score (P=0.008), and a higher proportion of severe WMH (P=0.043). Spearman correlation analysis demonstrated that serum 25(OH)D concentrations were positively associated with MoCA score (rs=0.185, P=0.019) while negatively related to the proportion of severe WMH (sWMH) (rs=-0.166, P=0.036).The association between 25(OH)D concentrations and MoCA score remained significant in linear regression (adjusted ß=0.012, 95%CI:0.001-0.203).Adjusted binary logistic regression analysis showed that the odds ratio of cognitive impairment with insufficient 25(OH)D concentration was 5.038 (95%CI:1.154-21.988) compared with the sufficient group and the sWMH (OR=2.728, 95%CI:1.230-6.051) was identified as an independent risk factor for cognitive decline in NICE patients. CONCLUSION: Serum 25(OH)D levels and white matter lesions were independently and significantly associated with cognitive impairment in NICE patients.


Assuntos
Leucoaraiose , Vitamina D , Substância Branca , Adulto , Humanos , Cognição , Estudos Prospectivos , Substância Branca/diagnóstico por imagem
3.
Neurol Ther ; 13(2): 373-387, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38263492

RESUMO

INTRODUCTION: The case fatality rate among patients with aneurysmal subarachnoid hemorrhage (aSAH) has decreased progressively, with numerous patients subjected to contemporary paradigms that minimize the use of agonizing therapeutic processes. The concept of the "Textbook Outcome" (TO), a composite outcome that highlights numerous favorable outcomes, was developed in the context of gastrointestinal tumor surgeries and expeditiously extended across diverse surgical spheres. The aim of this study was to explore the factors hindering the achievement of optimal prognoses in postinterventional aSAH patients, employ textbook outcomes, and establish predictive models. METHODS: We conducted a retrospective review of data from 1270 aSAH patients who received endovascular treatment between 2012 and 2018. We delineated an exemplary TO within the aSAH domain, characterized by favorable clinical results, minimal complications, and the absence of retreatments. This TO-oriented approach is explained within the manuscript. RESULTS: The findings revealed that preoperative intraventricular hemorrhage (IVH), preoperative Hunt and Hess grade (H&H) ≥ 3, World Federation of Neurosurgical Societies (WFNS) grade ≥ 3, the presence of blebs on the aneurysm, aneurysms situated at branching sites, and non-stent-assisted endovascular intervention were the strongest risk factors for not achieving textbook outcomes (non-"Textbook Outcome" [N-TO]). Decision curve analysis and calibration analyses revealed strong concordance between the predictions of the N-TO nomogram model and the actual observations. CONCLUSIONS: Treatment Outcomes hold significant practical value in clinical studies of aSAH patients receiving endovascular treatment. The likelihood of N-TOs was predicted by IVH, H&H grade ≥ 3, WFNS grade ≥ 2, presence o f bleb on the aneurysm, and aneurysms located at branching sites.

4.
bioRxiv ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38045409

RESUMO

Mitochondrial (MT) mutations serve as natural genetic markers for inferring clonal relationships using single cell sequencing data. However, the fundamental challenge of MT mutation-based lineage tracing is automated identification of informative MT mutations. Here, we introduced an open-source computational algorithm called "MitoTracer", which accurately identified clonally informative MT mutations and inferred evolutionary lineage from scRNA-seq or scATAC-seq samples. We benchmarked MitoTracer using the ground-truth experimental lineage sequencing data and demonstrated its superior performance over the existing methods measured by high sensitivity and specificity. MitoTracer is compatible with multiple single cell sequencing platforms. Its application to a cancer evolution dataset revealed the genes related to primary BRAF-inhibitor resistance from scRNA-seq data of BRAF-mutated cancer cells. Overall, our work provided a valuable tool for capturing real informative MT mutations and tracing the lineages among cells.

5.
ArXiv ; 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37292476

RESUMO

Designing biological sequences is an important challenge that requires satisfying complex constraints and thus is a natural problem to address with deep generative modeling. Diffusion generative models have achieved considerable success in many applications. Score-based generative stochastic differential equations (SDE) model is a continuous-time diffusion model framework that enjoys many benefits, but the originally proposed SDEs are not naturally designed for modeling discrete data. To develop generative SDE models for discrete data such as biological sequences, here we introduce a diffusion process defined in the probability simplex space with stationary distribution being the Dirichlet distribution. This makes diffusion in continuous space natural for modeling discrete data. We refer to this approach as Dirchlet diffusion score model. We demonstrate that this technique can generate samples that satisfy hard constraints using a Sudoku generation task. This generative model can also solve Sudoku, including hard puzzles, without additional training. Finally, we applied this approach to develop the first human promoter DNA sequence design model and showed that designed sequences share similar properties with natural promoter sequences.

6.
Cancer Cell ; 41(10): 1788-1802.e10, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37816332

RESUMO

Mitochondria (MT) participate in most metabolic activities of mammalian cells. A near-unidirectional mitochondrial transfer from T cells to cancer cells was recently observed to "metabolically empower" cancer cells while "depleting immune cells," providing new insights into tumor-T cell interaction and immune evasion. Here, we leverage single-cell RNA-seq technology and introduce MERCI, a statistical deconvolution method for tracing and quantifying mitochondrial trafficking between cancer and T cells. Through rigorous benchmarking and validation, MERCI accurately predicts the recipient cells and their relative mitochondrial compositions. Application of MERCI to human cancer samples identifies a reproducible MT transfer phenotype, with its signature genes involved in cytoskeleton remodeling, energy production, and TNF-α signaling pathways. Moreover, MT transfer is associated with increased cell cycle activity and poor clinical outcome across different cancer types. In summary, MERCI enables systematic investigation of an understudied aspect of tumor-T cell interactions that may lead to the development of therapeutic opportunities.


Assuntos
DNA Mitocondrial , Neoplasias , Animais , Humanos , DNA Mitocondrial/genética , Linfócitos T/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Mamíferos/genética , Mamíferos/metabolismo
7.
Front Aging Neurosci ; 14: 1023195, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36533171

RESUMO

Background: Both inflammation and cerebral white matter injury are closely associated with vascular cognitive impairment (VCI). The aim of this study was to analyze the correlation between peripheral serological markers, white matter injury, and cognitive function in patients with non-disabling ischemic cerebrovascular events (NICE); to identify potential biological markers for the diagnosis and prediction of VCI; and to provide a basis for the early diagnosis and intervention of VCI. Methods: We collected clinical data, along with demographic and medical history data, from 151 NICE patients. Fasting venous blood samples were collected. Based on the Montreal Cognitive Assessment (MoCA) after admission, we divided the patients into normal cognitive function (NCF) and VCI groups, and then classified them into mild white matter hyperintensity (mWMH) and severe white matter hyperintensity (sWMH) based on Fazekas scores. The differences in serological marker levels were compared between the cognitive function groups and the white matter hyperintensity groups. Binary logistic regression models and receiver operating characteristic curves were used to analyze the diagnostic predictive value of serological markers for VCI in patients with NICE and in the white matter hyperintensity subgroups. Results: Among 151 patients with NICE, 95 were male and 56 were female. Lymphocyte count (OR = 0.405, p = 0.010, 95% CI [0.201, 0.806]), red blood cell count (OR = 0.433, p = 0.010, 95% CI [0.228, 0.821]), and hemoglobin level (OR = 0.979, p = 0.046, 95% CI [0.958, 0.999]) were protective factors for cognitive function in patients with NICE. The sWMH group had a higher age, granulocyte/lymphoid ratio (NLR), and neutrophil percentage but a lower MoCA score, hemoglobin level, and lymphocyte count than the mWMH group. In the mWMH group, lymphocyte count (AUC = 0.713, p = 0.003, 95% CI [0.593, 0.833]) had an acceptable predictive value for the diagnosis of VCI, whereas white blood cell count (AUC = 0.672, p = 0.011, 95% CI [0.545, 0.799]), red blood cell count (AUC = 0.665, p = 0.014, 95% CI [0.545, 0.784]), and hemoglobin level (AUC = 0.634, p = 0.047, 95% CI [0.502, 0.765]) had marginal predictive value for the diagnosis of VCI. In the sWMH group, no significant differences were found in serological markers between the NCF and VCI groups. Conclusion: Lymphocyte count, red blood cell count, and hemoglobin level were independent protective factors for cognitive function in patients with NICE; they can be used as potential biological markers to distinguish VCI in patients with NICE and are applicable to subgroups of patients with mWMH.

8.
Eur J Med Res ; 27(1): 309, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36572939

RESUMO

BACKGROUND: Chronic subdural hematoma (CSDH) is a common disease that forms between the dura and arachnoid membranes of the brain. With the development of medications and surgery, significant progress has been made in the diagnosis and treatment of CSDH. However, there is no comprehensive analysis available on CSDH-related studies published in the literature. This study aimed to collect and analyze CSDH-related studies published since the twenty-first century using bibliometric analysis and to summarize the current status of research in this field for the sake of providing systematic data for further study of CSDH. METHODS: CSDH-related studies were searched in the Web of Science Core Collection (WoSCC) database using the Medical Subject Heading (MeSH) term 'chronic subdural hematoma'. Data analysis and visualization were performed by R and CiteSpace software. RESULTS: This study retrieved 1424 CSDH-related articles published since the beginning of the twenty-first century. There was a general increase in both the number of published articles and the mean number of citations. The authors, institutions and journals that contributed the most to the field of CSDH were Jianning Zhang, Tianjin Medical University, and world neurosurgery, respectively. The reference co-citation network identified 13 clusters with significant modularity Q scores and silhouette scores (Q = 0.7124, S = 0.8536). The major research categories were (1) evolution of the therapeutic method and (2) the etiology and pathology of CSDH. Keyword analysis revealed that 'middle meningeal artery embolization' was the latest burst keyword. CONCLUSIONS: This study identified the most influential countries, authors, institutions and journals contributing to CSDH research and discussed the hotspots and the latest subjects of CSDH research.


Assuntos
Embolização Terapêutica , Hematoma Subdural Crônico , Humanos , Embolização Terapêutica/métodos , Hematoma Subdural Crônico/cirurgia , Artérias Meníngeas , Procedimentos Neurocirúrgicos , Bibliometria
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