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1.
Nature ; 627(8005): 847-853, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38480885

RESUMO

Plant nucleotide-binding leucine-rich repeat (NLR) immune receptors with an N-terminal Toll/interleukin-1 receptor (TIR) domain mediate recognition of strain-specific pathogen effectors, typically via their C-terminal ligand-sensing domains1. Effector binding enables TIR-encoded enzymatic activities that are required for TIR-NLR (TNL)-mediated immunity2,3. Many truncated TNL proteins lack effector-sensing domains but retain similar enzymatic and immune activities4,5. The mechanism underlying the activation of these TIR domain proteins remain unclear. Here we show that binding of the TIR substrates NAD+ and ATP induces phase separation of TIR domain proteins in vitro. A similar condensation occurs with a TIR domain protein expressed via its native promoter in response to pathogen inoculation in planta. The formation of TIR condensates is mediated by conserved self-association interfaces and a predicted intrinsically disordered loop region of TIRs. Mutations that disrupt TIR condensates impair the cell death activity of TIR domain proteins. Our data reveal phase separation as a mechanism for the activation of TIR domain proteins and provide insight into substrate-induced autonomous activation of TIR signalling to confer plant immunity.


Assuntos
Trifosfato de Adenosina , Arabidopsis , NAD , Nicotiana , Separação de Fases , Proteínas de Plantas , Domínios Proteicos , Trifosfato de Adenosina/metabolismo , Arabidopsis/genética , Arabidopsis/imunologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/imunologia , Proteínas de Arabidopsis/metabolismo , Morte Celular , Mutação , NAD/metabolismo , Nicotiana/genética , Nicotiana/imunologia , Nicotiana/metabolismo , Proteínas NLR/química , Proteínas NLR/genética , Proteínas NLR/imunologia , Proteínas NLR/metabolismo , Doenças das Plantas/imunologia , Imunidade Vegetal/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Domínios Proteicos/genética , Receptores Imunológicos/química , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Receptores Imunológicos/metabolismo , Transdução de Sinais , Receptores Toll-Like/química , Receptores de Interleucina-1/química
2.
J Immunol ; 213(4): 481-493, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38949555

RESUMO

Aberrant activity of NLRP3 has been shown associations with severe diseases. Palmitoylation is a kind of protein post-translational modification, which has been shown to regulate cancer development and the innate immune system. Here, we showed that NLRP3 is palmitoylated at Cys419 and that palmitoyltransferase ZDHHC17 is the predominant enzyme that mediates NLRP3 palmitoylation and promotes NLRP3 activation by interacting with NLRP3 and facilitating NIMA-related kinase 7 (NEK7)-NLRP3 interactions. Blockade of NLRP3 palmitoylation by a palmitoylation inhibitor, 2-bromopalmitate, effectively inhibited NLRP3 activation in vitro. Also, in a dextran sulfate sodium-induced colitis model in mice, 2-bromopalmitate application could attenuate weight loss, improve the survival rate, and rescue pathological changes in the colon of mice. Overall, our study reveals that palmitoylation of NLPR3 modulates inflammasome activation and inflammatory bowel disease development. We propose that drugs targeting NLRP3 palmitoylation could be promising candidates in the treatment of NLRP3-mediated inflammatory diseases.


Assuntos
Aciltransferases , Colite , Inflamassomos , Doenças Inflamatórias Intestinais , Lipoilação , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamassomos/metabolismo , Camundongos , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/metabolismo , Humanos , Aciltransferases/metabolismo , Colite/imunologia , Colite/induzido quimicamente , Colite/metabolismo , Sulfato de Dextrana/toxicidade , Camundongos Endogâmicos C57BL , Quinases Relacionadas a NIMA/metabolismo , Palmitatos/farmacologia , Modelos Animais de Doenças , Células HEK293 , Processamento de Proteína Pós-Traducional
3.
Plant Physiol ; 195(1): 534-551, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38365225

RESUMO

Gymnosperms are mostly dioecious, and their staminate strobili undergo a longer developmental period than those of angiosperms. However, the underlying molecular mechanisms remain unclear. This study aimed to identify key genes and pathways involved in staminate strobilus development and dehiscence in Torreya grandis. Through weighted gene co-expression network analysis (WGCNA), we identified fast elongation-related genes enriched in carbon metabolism and auxin signal transduction, whereas dehiscence-related genes were abundant in alpha-linolenic acid metabolism and the phenylpropanoid pathway. Based on WGCNA, we also identified PHYTOCHROME-INTERACTING FACTOR4 (TgPIF4) as a potential regulator for fast elongation of staminate strobilus and 2 WRKY proteins (TgWRKY3 and TgWRKY31) as potential regulators for staminate strobilus dehiscence. Multiple protein-DNA interaction analyses showed that TgPIF4 directly activates the expression of TRANSPORT INHIBITOR RESPONSE2 (TgTIR2) and NADP-MALIC ENZYME (TgNADP-ME). Overexpression of TgPIF4 significantly promoted staminate strobilus elongation by elevating auxin signal transduction and pyruvate content. TgWRKY3 and TgWRKY31 bind to the promoters of the lignin biosynthesis gene PHENYLALANINE AMMONIA-LYASE (TgPAL) and jasmonic acid metabolism gene JASMONATE O-METHYLTRANSFERASE (TgJMT), respectively, and directly activate their transcription. Overexpression of TgWRKY3 and TgWRKY31 in the staminate strobilus led to early dehiscence, accompanied by increased lignin and methyl jasmonate levels, respectively. Collectively, our findings offer a perspective for understanding the growth of staminate strobili in gymnosperms.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Cycadopsida/genética , Cycadopsida/metabolismo , Ciclopentanos/metabolismo , Oxilipinas/metabolismo
4.
Mod Pathol ; 37(4): 100439, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38286221

RESUMO

This work puts forth and demonstrates the utility of a reporting framework for collecting and evaluating annotations of medical images used for training and testing artificial intelligence (AI) models in assisting detection and diagnosis. AI has unique reporting requirements, as shown by the AI extensions to the Consolidated Standards of Reporting Trials (CONSORT) and Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) checklists and the proposed AI extensions to the Standards for Reporting Diagnostic Accuracy (STARD) and Transparent Reporting of a Multivariable Prediction model for Individual Prognosis or Diagnosis (TRIPOD) checklists. AI for detection and/or diagnostic image analysis requires complete, reproducible, and transparent reporting of the annotations and metadata used in training and testing data sets. In an earlier work by other researchers, an annotation workflow and quality checklist for computational pathology annotations were proposed. In this manuscript, we operationalize this workflow into an evaluable quality checklist that applies to any reader-interpreted medical images, and we demonstrate its use for an annotation effort in digital pathology. We refer to this quality framework as the Collection and Evaluation of Annotations for Reproducible Reporting of Artificial Intelligence (CLEARR-AI).


Assuntos
Inteligência Artificial , Lista de Checagem , Humanos , Prognóstico , Processamento de Imagem Assistida por Computador , Projetos de Pesquisa
5.
New Phytol ; 243(5): 1823-1839, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39005107

RESUMO

Cone enlargement is a crucial process for seed production and reproduction in gymnosperms. Most of our knowledge of cone development is derived from observing anatomical structure during gametophyte development. Therefore, the exact molecular mechanism underlying cone enlargement after fertilization is poorly understood. Here, we demonstrate that sucrose promotes cone enlargement in Torreya grandis, a gymnosperm species with relatively low rates of cone enlargement, via the TgNGA1-TgWRKY47-TgEXPA2 pathway. Cell expansion plays a significant role in cone enlargement in T. grandis. 13C labeling and sucrose feeding experiments indicated that sucrose-induced changes in cell size and number contribute to cone enlargement in this species. RNA-sequencing analysis, transient overexpression in T. grandis cones, and stable overexpression in tomato (Solanum lycopersicum) suggested that the expansin gene TgEXPA2 positively regulates cell expansion in T. grandis cones. The WRKY transcription factor TgWRKY47 directly enhances TgEXPA2 expression by binding to its promoter. Additionally, the NGATHA transcription factor TgNGA1 directly interacts with TgWRKY47. This interaction suppresses the DNA-binding ability of TgWRKY47, thereby reducing its transcriptional activation on TgEXPA2 without affecting the transactivation ability of TgWRKY47. Our findings establish a link between sucrose and cone enlargement in T. grandis and elucidate the potential underlying molecular mechanism.


Assuntos
Proteínas de Plantas , Sacarose , Taxaceae , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Sacarose/metabolismo , Sacarose/farmacologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Taxaceae/genética , Taxaceae/crescimento & desenvolvimento
6.
Ann Surg Oncol ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008209

RESUMO

BACKGROUND: Evidence is limited for the treatment of pancreatic cancer among minimally invasive pancreatoduodenectomy. METHODS: This retrospective analysis evaluated patients who underwent robotic pancreaticoduodenectomy (RPD) or laparoscopic pancreaticoduodenectomy (LPD) from April 2016 to April 2023. Their baseline and perioperative data, including operative time, R0 resection rates, and severe complications rates, were analyzed, and the follow-up data, such as disease-free survival (DFS) and overall survival (OS), were collected. RESULTS: A total of 253 cases of LPD and RPD were performed, and 101 cases with pancreatic cancer were included, of which 54 were LPD and 47 were RPD. The conversion rate (4.3% vs. 29.6%, p = 0.001) and blood loss (400 vs. 575 mL, p < 0.05) were lower in the RPD group. No significant difference was observed between the two groups in terms of operative time, vessel resection rates, and TNM-stage diagnosis; however, R0 resection rates (80.9% vs. 70.4%) and lymph node harvest (24.2 vs. 21.9) had a higher tendency in the RPD group, and postoperative length of stay was shorter in the RPD cohort (11 vs. 13 days). Moreover, improved 1- to 3-years DFS (75.7%, 61.7%, and 36.0% vs. 59.0%, 35.6%, and 21.9%) and OS (94.7%, 84.7%, and 50.8% vs. 84.1%, 63.6%, and 45.5%) was found in the RPD group in comparison with the LPD group. CONCLUSIONS: RPD had advantages in surgical safety and oncological outcomes compared with LPD, but was similar to the latter in perioperative outcomes. Long-term outcomes require further study.

7.
Ann Surg Oncol ; 31(7): 4250-4260, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38334847

RESUMO

BACKGROUND: The prognosis of limited-stage small cell lung cancer (LS-SCLC) after surgery usually is estimated at diagnosis, but how the prognosis actually evolves over time for patients who survived for a predefined time is unknown. METHODS: Data on patients with a diagnosis of LS-SCLC after surgery between 2004 and 2015 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. The 5-year conditional cancer-specific survival (CCSS) and conditional overall survival (COS) were calculated. RESULTS: This study analyzed 997 patients (555 women, 55.7%) with a median age, of 67 years (interquartile range [IQR], 60-73 years). The 5-year CCSS and COS increased from 44.7% and 38.3%, respectively, at diagnosis to 83.7% and 67.9% at 5 years after diagnosis. Although there were large differences with different stages (stages I, II, and III) at diagnosis (respectively 59.5%, 28.4%; 28.1% for CCSS and 50.6%, 24.8%, and 23.6% for COS), the gap decreased with time, and the rates were similar after 5 years (respectively 85.0%, 80.3%, and 79.4% for CCSS; 65.6%, 56.9%, and 61.3% for COS). The 5-year conditional survival for the patients who received lobectomy was better than for those who received sublobectomy or pneumonectomy. Multivariable analyses showed that only age and resection type were independent predictors for CCSS and COS, respectively, throughout the period. CONCLUSION: Conditional survival estimates for LS-SCLC generally increased over time, with the most significant improvement in patients with advanced stage of disease. Resection type and old age represented extremely important determinants of prognosis after a lengthy event-free follow-up period.


Assuntos
Neoplasias Pulmonares , Estadiamento de Neoplasias , Programa de SEER , Carcinoma de Pequenas Células do Pulmão , Humanos , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Feminino , Carcinoma de Pequenas Células do Pulmão/cirurgia , Carcinoma de Pequenas Células do Pulmão/mortalidade , Carcinoma de Pequenas Células do Pulmão/patologia , Pessoa de Meia-Idade , Masculino , Taxa de Sobrevida , Idoso , Prognóstico , Seguimentos , Pneumonectomia/mortalidade , Estudos de Coortes
8.
BMC Cancer ; 24(1): 210, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360598

RESUMO

OBJECTIVE: This study was designed to investigate the regulatory effects of kinesin family member (KIF) 23 on anaplastic thyroid cancer (ATC) cell viability and migration and the underlying mechanism. METHODS: Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to analyze the levels of KIF23 in ATC cells. Besides, the effects of KIF23 and sirtuin (SIRT) 7 on the viability and migration of ATC cells were detected using cell counting kit-8, transwell and wound healing assays. The interaction between SIRT7 and KIF23 was evaluated by co-immunoprecipitation (Co-IP) assay. The succinylation (succ) of KIF23 was analyzed by western blot. RESULTS: The KIF23 expression was upregulated in ATC cells. Silencing of KIF23 suppressed the viability and migration of 8505C and BCPAP cells. The KIF23-succ level was decreased in ATC cells. SIRT7 interacted with KIF23 to inhibit the succinylation of KIF23 at K537 site in human embryonic kidney (HEK)-293T cells. Overexpression of SIRT7 enhanced the protein stability of KIF23 in HEK-293T cells. Besides, overexpression of KIF23 promoted the viability and migration of 8505C and BCPAP cells, which was partly blocked by silenced SIRT7. CONCLUSIONS: SIRT7 promoted the proliferation and migration of ATC cells by regulating the desuccinylation of KIF23.


Assuntos
Sirtuínas , Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Carcinoma Anaplásico da Tireoide/genética , Carcinoma Anaplásico da Tireoide/metabolismo , Linhagem Celular Tumoral , Apoptose , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Proliferação de Células/genética , Proteínas Associadas aos Microtúbulos , Sirtuínas/genética , Sirtuínas/farmacologia
9.
Mol Cell Biochem ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409514

RESUMO

This study aimed to decipher the mechanism of circular ribonucleic acids (circRNAs) in lower extremity arteriosclerosis obliterans (LEASO). First, bioinformatics analysis was performed for screening significantly down-regulated cardiac specific circRNA-circHAT1 in LEASO. The expression of circHAT1 in LEASO clinical samples was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The protein expression of splicing factor arginine/serine-rich 1 (SFRS1), α-smooth muscle actin (α-SMA), Calponin (CNN1), cyclin D1 (CNND1) and smooth muscle myosin heavy chain 11 (SMHC) in vascular smooth muscle cells (VSMCs) was detected by Western blotting. Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU) and Transwell assays were used to evaluate cell proliferation and migration, respectively. RNA immunoprecipitation (RNA-IP) and RNA pulldown verified the interaction between SFRS1 and circHAT1. By reanalyzing the dataset GSE77278, circHAT1 related to VSMC phenotype conversion was screened, and circHAT1 was found to be significantly reduced in peripheral blood mononuclear cells (PBMCs) of LEASO patients compared with healthy controls. Knockdown of circHAT1 significantly promoted the proliferation and migration of VSMC cells and decreased the expression levels of contractile markers. However, overexpression of circHAT1 induced the opposite cell phenotype and promoted the transformation of VSMCs from synthetic to contractile. Besides, overexpression of circHAT1 inhibited platelet-derived growth factor-BB (PDGF-BB)-induced phenotype switch of VSMC cells. Mechanistically, SFRS1 is a direct target of circHAT1 to mediate phenotype switch, proliferation and migration of VSMCs. Overall, circHAT1 regulates SFRS1 to inhibit the cell proliferation, migration and phenotype switch of VSMCs, suggesting that it may be a potential therapeutic target for LEASO.

10.
J Org Chem ; 89(12): 8896-8905, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38856706

RESUMO

Endocyclic 1-azaallyl anions engage allyl acetates in a palladium-catalyzed allylation followed by reduction to give unprotected 2-(hetero)aryl-3-allylpiperidines and 2-allyl-3-arylmorpholines, products not easily accessible by other means. The allyl group is then readily transformed into a variety of functional groups. Preliminary studies on the asymmetric variant of the reaction using an enantiomerically pure BI-DIME-type ligand provide the product with moderate enantioselectivity. Computational studies suggest that energy barriers of inner-sphere reductive elimination and outer-sphere nucleophilic substitution are almost the same, which makes both of them possible reaction pathways. In addition, the inner-sphere mechanism displays an enantiodiscriminating C-C bond forming step, while the outer-sphere mechanism is much less selective, which combined to give the asymmetric variant of the reaction moderate enantioselectivity.

11.
Surg Endosc ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164439

RESUMO

BACKGROUND: There are limited data on the effect of different sutures and surgical approaches on the quality of pancreaticojejunostomy in minimally invasive pancreaticoduodenectomy (MIPD). This study compares the incidence of clinically relevant postoperative pancreatic fistula (CR-POPF) between the use of barbed sutures (BSs) and conventional sutures (CSs). METHODS: A retrospective cohort study was conducted on 253 consecutive patients who had undergone MIPD from July 2016 to April 2023. Patients were excluded if conversion to open surgery or open anastomosis was necessary. 220 patients were enrolled and divided into BS (n = 148) and CS (n = 72) groups. After 1:1 propensity score matching (PSM), 67 cases remained in each group. Univariate and multivariate analyses identified factors associated with CR-POPF. Comparisons were also made between laparoscopic (LPD) and robotic (RPD) pancreaticoduodenectomy. RESULTS: After PSM, BSs were associated with significantly lower rates of CR-POPF (7.5 vs. 22.4%, P = 0.015) and severe complications (Clavien-Dindo ≥ III) (7.5vs. 19.4%, P = 0.043). No significant differences were found in operative time, length of postoperative hospital stay, or other major morbidities. Multivariate analyses revealed BMI ≥ 22 kg/m2 (OR = 5.048, 95% CI: 1.256-20.287, P = 0.023) and the use of BSs (OR = 0.196, 95% CI: 0.059-0.653, P = 0.008) as the independent predictors of CR-POPF. There were no significant differences in postoperative outcomes between the LPD and RPD groups, but RPD was associated with significantly shorter operative time (402.8 min vs. 429.4 min, P = 0.015). CONCLUSIONS: In conclusion, using BSs for PJ during MIPD is feasible and has the potential to reduce CR-POPF and severe complications.

12.
BMC Med Inform Decis Mak ; 24(1): 176, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907208

RESUMO

BACKGROUND: Patient-reported outcome (PRO) is a distinct and indispensable dimension of clinical characteristics and recent advances have made remote PRO measurement possible. Sex difference in PRO of Parkinson's disease (PD) is hardly extensively researched. METHODS: A smartphone-based self-management platform, offering remote PRO measurement for PD patients, has been developed. A total of 1828 PD patients, including 1001 male patients and 827 female patients, were enrolled and completed their PRO submission through this platform. RESULTS: Sex differences in PROs have been identified. The female group had a significantly lower height, weight, and body mass index (BMI) than the male group (P < 0.001). For motor symptoms, a higher proportion of patients reporting dyskinesia was observed in the female group. For non-motor symptoms, there is a higher percentage (P < 0.001) as well as severity (P = 0.016) of depression in the female group. More male patients reported hyposmia, lisp, drooling, dysuria, frequent urination, hypersexuality, impotence, daytime sleepiness, and apathy than females (P < 0.05). In contrast, more female patients reported headache, palpation, body pain, anorexia, nausea, urinal incontinence, anxiety, insomnia (P < 0.05) than males. CONCLUSIONS: We provide evidence for sex differences in PD through the data collected from our platform. These results highlighted the importance of gender in clinical decision-making, and also support the feasibility of remote PRO measurement through a smartphone-based self-management platform in patients with PD.


Assuntos
Doença de Parkinson , Medidas de Resultados Relatados pelo Paciente , Autogestão , Smartphone , Humanos , Doença de Parkinson/terapia , Masculino , Feminino , Projetos Piloto , Estudos Transversais , Pessoa de Meia-Idade , Idoso , Fatores Sexuais , Aplicativos Móveis
13.
J Integr Neurosci ; 23(6): 117, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38940088

RESUMO

PURPOSE: To determine whether individuals with subjective cognitive decline (SCD) have changes in whole-brain network characteristics and intracerebral node characteristics in the structural network, and whether there is a difference between SCD with and without Apolipoprotein E4 (APOEε4). METHODS: This cross-sectional study included 36 individuals without SCD without APOEε4 (healthy control, HC group), 21 individuals with SCD with APOEε4 (APOEε4+ group), and 33 individuals with SCD without APOEε4 (APOEε4- group). The white matter structural network was constructed using the fractional anisotropy (FA) based deterministic fiber tracking method. Graph theory was used to analyze the whole-brain network characteristics and intracerebral node characteristics of the three groups. RESULTS: Regarding the whole-brain network characteristics, all three groups exhibited small-worldness in their structural networks. The clustering coefficient (Cp) and local efficiency (Eloc) in the APOEε4+ and APOEε4- groups were significantly lower than in the HC group (p < 0.05), but no significant difference in Cp or Eloc was observed between the APOEε4+ and APOEε4- groups. Regarding intracerebral node characteristics, there were significant differences in some brain regions, mainly the default mode network (DMN), the occipital lobe, the temporal lobe, and subcortical regions. The change in intracerebral node characteristics was different between the APOEε4+ group and the APOEε4- group. CONCLUSIONS: Individuals with SCD demonstrate changes in whole-brain network characteristics and intracerebral node characteristics in the structural network. Moreover, differences exist between APOEε4+ and APOEε4- individuals.


Assuntos
Apolipoproteína E4 , Disfunção Cognitiva , Rede Nervosa , Substância Branca , Humanos , Apolipoproteína E4/genética , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Masculino , Feminino , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/patologia , Estudos Transversais , Idoso , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Rede Nervosa/fisiopatologia , Imagem de Tensor de Difusão , Autoavaliação Diagnóstica
14.
Angew Chem Int Ed Engl ; 63(20): e202401498, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38499469

RESUMO

Herein, multiple types of chiral Os(II) complexes have been designed to address the appealing yet challenging asymmetric C(sp3)-H functionalization, among which the Os(II)/Salox species is found to be the most efficient for precise stereocontrol in realizing the asymmetric C(sp3)-H amidation. As exemplified by the enantioenriched pyrrolidinone synthesis, such tailored Os(II)/Salox catalyst efficiently enables an intramolecular site-/enantioselective C(sp3)-H amidation in the γ-position of dioxazolone substrates, in which benzyl, propargyl and allyl groups bearing various substituted forms are well compatible, affording the corresponding chiral γ-lactam products with good er values (up to 99 : 1) and diverse functionality (>35 examples). The unique performance advantage of the developed chiral Os(II)/Salox system in terms of the catalytic energy profile and the chiral induction has been further clarified by integrated experimental and computational studies.

15.
Entropy (Basel) ; 26(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38275492

RESUMO

Anticipatory dynamics (AD) is unusual in that responses from an information receiver can appear ahead of triggers from the source, and direction of information flow (DIF) is needed to establish causality. Although it is believed that anticipatory dynamics is important for animals' survival, natural examples are rare. Time series (trajectories) from a pair of interacting zebrafish are used to look for the existence of AD in natural systems. In order to obtain the DIF between the two trajectories, we have made use of a special experimental design to designate information source. However, we have also used common statistical tools such as Granger causality and transfer entropy to detect DIF. In our experiments, we found that a majority of the fish pairs do not show any anticipatory behaviors and only a few pairs displayed possible AD. Interestingly, for fish in this latter group, they do not display AD all the time. Our findings suggest that the formation of schooling of fish might not need the help of AD, and new tools are needed in the detection of causality in AD system.

17.
Adv Sci (Weinh) ; 11(17): e2307152, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38417119

RESUMO

Dopant-free hole transport layers (HTLs) are crucial in enhancing perovskite solar cells (pero-SCs). Nevertheless, conventional processing of these HTL materials involves using toxic solvents, which gives rise to substantial environmental concerns and renders them unsuitable for large-scale industrial production. Consequently, there is a pressing need to develop dopant-free HTL materials processed using green solvents to facilitate the production of high-performance pero-SCs. Recently, several strategies have been developed to simultaneously improve the solubility of these materials and regulate molecular stacking for high hole mobility. In this review, a comprehensive overview of the methodologies utilized in developing dopant-free HTL materials processed from green solvents is provided. First, the study provides a brief overview of fundamental information about green solvents and Hansen solubility parameters, which can serve as a guideline for the molecular design of optimal HTL materials. Second, the intrinsic relationships between molecular structure, solubility in green solvents, molecular stacking, and device performance are discussed. Finally, conclusions and perspectives are presented along with the rational design of highly efficient, stable, and green solvent-processable dopant-free HTL materials.

18.
PLoS One ; 19(7): e0298102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38954731

RESUMO

Brain tumors pose a significant threat to health, and their early detection and classification are crucial. Currently, the diagnosis heavily relies on pathologists conducting time-consuming morphological examinations of brain images, leading to subjective outcomes and potential misdiagnoses. In response to these challenges, this study proposes an improved Vision Transformer-based algorithm for human brain tumor classification. To overcome the limitations of small existing datasets, Homomorphic Filtering, Channels Contrast Limited Adaptive Histogram Equalization, and Unsharp Masking techniques are applied to enrich dataset images, enhancing information and improving model generalization. Addressing the limitation of the Vision Transformer's self-attention structure in capturing input token sequences, a novel relative position encoding method is employed to enhance the overall predictive capabilities of the model. Furthermore, the introduction of residual structures in the Multi-Layer Perceptron tackles convergence degradation during training, leading to faster convergence and enhanced algorithm accuracy. Finally, this study comprehensively analyzes the network model's performance on validation sets in terms of accuracy, precision, and recall. Experimental results demonstrate that the proposed model achieves a classification accuracy of 91.36% on an augmented open-source brain tumor dataset, surpassing the original VIT-B/16 accuracy by 5.54%. This validates the effectiveness of the proposed approach in brain tumor classification, offering potential reference for clinical diagnoses by medical practitioners.


Assuntos
Algoritmos , Neoplasias Encefálicas , Humanos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/diagnóstico por imagem , Redes Neurais de Computação
19.
Org Lett ; 26(28): 5972-5977, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38968591

RESUMO

Unprotected alicyclic amines undergo α-C-H bond phosphonylation via a two-stage one-pot process involving the oxidation of amine-derived lithium amides with simple ketone oxidants, generating transient imines which are then captured with phosphites or phosphine oxides. Amines with an existing α-substituent undergo regioselective α'-phosphonylation. Amine α-arylation and α'-phosphonylation can be combined, generating a difunctionalized product in a single operation.

20.
Surg Obes Relat Dis ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38782612

RESUMO

BACKGROUND: Bile acids can stimulate the secretion of glucagon-like peptide-1 (GLP-1) and be mostly reabsorbed in the ileum. OBJECTIVES: We aimed to investigate whether ileum excision could reverse the glucose improvement after biliopancreatic diversion with duodenal switch (BPD/DS). SETTING: Peking Union Medical College Hospital. METHODS: Thirty diabetic rats were randomly divided into the BPD/DS group, BPD/DS plus ileectomy (BDI) group, and control group. The fasting blood glucose, bile acids, and glucagon-like peptide-1(GLP-1) levels in plasma samples were analyzed. RESULTS: In postoperative week 20, the fasting blood glucose level in the BDI group was significantly higher than that in the BPD/DS group (11.5 ± 1.4 mmol/L versus 7.6 ± 1.0 mmol/L, P < .001), and the AUCOGTT value was also significantly higher than that in the BPD/DS group (2186.1 ± 237.2 mmol/L·min versus 1551.2 ± 136.9 mmol/L·min, P < .001). The plasma level of bile acids in the BDI group was lower than that in the BPD/DS group (P = .012) and was not significantly different from that in the control group (P = .629). The plasma level of GLP-1 in the BDI group was lower than that in the BPD/DS group (P = .009) and was not significantly different from that in the control group (P = .530). Moreover, the intestinal TGR5 expression in the BDI group was significantly lower than that in the BPD/DS group (P < .001). CONCLUSIONS: The results show that excision of the ileum can partially reverse the improvement in glucose metabolism after BPD/DS.

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