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1.
Cell ; 186(1): 98-111.e21, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36608662

RESUMO

In eukaryotes, DNA replication initiation requires assembly and activation of the minichromosome maintenance (MCM) 2-7 double hexamer (DH) to melt origin DNA strands. However, the mechanism for this initial melting is unknown. Here, we report a 2.59-Å cryo-electron microscopy structure of the human MCM-DH (hMCM-DH), also known as the pre-replication complex. In this structure, the hMCM-DH with a constricted central channel untwists and stretches the DNA strands such that almost a half turn of the bound duplex DNA is distorted with 1 base pair completely separated, generating an initial open structure (IOS) at the hexamer junction. Disturbing the IOS inhibits DH formation and replication initiation. Mapping of hMCM-DH footprints indicates that IOSs are distributed across the genome in large clusters aligning well with initiation zones designed for stochastic origin firing. This work unravels an intrinsic mechanism that couples DH formation with initial DNA melting to license replication initiation in human cells.


Assuntos
Replicação do DNA , Humanos , Proteínas de Ciclo Celular/metabolismo , Microscopia Crioeletrônica , Proteínas de Ligação a DNA/metabolismo , Proteínas de Manutenção de Minicromossomo/metabolismo , Origem de Replicação
2.
Mol Cell ; 68(1): 185-197.e6, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28943315

RESUMO

Many infections and stress signals can rapidly activate the NLRP3 inflammasome to elicit robust inflammatory responses. This activation requires a priming step, which is thought to be mainly for upregulating NLRP3 transcription. However, recent studies report that the NLRP3 inflammasome can be activated independently of transcription, suggesting that the priming process has unknown essential regulatory steps. Here, we report that JNK1-mediated NLRP3 phosphorylation at S194 is a critical priming event and is essential for NLRP3 inflammasome activation. We show that NLRP3 inflammasome activation is disrupted in NLRP3-S194A knockin mice. JNK1-mediated NLRP3 S194 phosphorylation is critical for NLRP3 deubiquitination and facilitates its self-association and the subsequent inflammasome assembly. Importantly, we demonstrate that blocking S194 phosphorylation prevents NLRP3 inflammasome activation in cryopyrin-associated periodic syndromes (CAPS). Thus, our study reveals a key priming molecular event that is a prerequisite for NLRP3 inflammasome activation. Inhibiting NLRP3 phosphorylation could be an effective treatment for NLRP3-related diseases.


Assuntos
Inflamassomos/genética , Macrófagos/imunologia , Proteína Quinase 8 Ativada por Mitógeno/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Choque Séptico/genética , Sequência de Aminoácidos , Animais , Enzimas Desubiquitinantes/genética , Enzimas Desubiquitinantes/imunologia , Escherichia coli/química , Feminino , Regulação da Expressão Gênica , Células HEK293 , Humanos , Inflamassomos/imunologia , Lipopolissacarídeos/farmacologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Transgênicos , Proteína Quinase 8 Ativada por Mitógeno/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/deficiência , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Fosforilação , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Choque Séptico/induzido quimicamente , Choque Séptico/mortalidade , Choque Séptico/patologia , Transdução de Sinais , Análise de Sobrevida
3.
PLoS Med ; 21(5): e1004389, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38728364

RESUMO

BACKGROUND: It remains unclear whether intensification of the chemotherapy backbone in tandem with an anti-EGFR can confer superior clinical outcomes in a cohort of RAS/BRAF wild-type colorectal cancer (CRC) patients with initially unresectable colorectal liver metastases (CRLM). To that end, we sought to comparatively evaluate the efficacy and safety of cetuximab plus FOLFOXIRI (triplet arm) versus cetuximab plus FOLFOX (doublet arm) as a conversion regimen (i.e., unresectable to resectable) in CRC patients with unresectable CRLM. METHODS AND FINDINGS: This open-label, randomized clinical trial was conducted from April 2018 to December 2022 in 7 medical centers across China, enrolling 146 RAS/BRAF wild-type CRC patients with initially unresectable CRLM. A stratified blocked randomization method was utilized to assign patients (1:1) to either the cetuximab plus FOLFOXIRI (n = 72) or cetuximab plus FOLFOX (n = 74) treatment arms. Stratification factors were tumor location (left versus right) and resectability (technically unresectable versus ≥5 metastases). The primary outcome was the objective response rate (ORR). Secondary outcomes included the median depth of tumor response (DpR), early tumor shrinkage (ETS), R0 resection rate, progression-free survival (PFS), overall survival (not mature at the time of analysis), and safety profile. Radiological tumor evaluations were conducted by radiologists blinded to the group allocation. Primary efficacy analyses were conducted based on the intention-to-treat population, while safety analyses were performed on patients who received at least 1 line of chemotherapy. A total of 14 patients (9.6%) were lost to follow-up (9 in the doublet arm and 5 in the triplet arm). The ORR was comparable following adjustment for stratification factors, with 84.7% versus 79.7% in the triplet and doublet arms, respectively (odds ratio [OR] 0.70; 95% confidence intervals [CI] [0.30, 1.67], Chi-square p = 0.42). Moreover, the ETS rate showed no significant difference between the triplet and doublet arms (80.6% (58/72) versus 77.0% (57/74), OR 0.82, 95% CI [0.37, 1.83], Chi-square p = 0.63). Although median DpR was higher in the triplet therapy group (59.6%, interquartile range [IQR], [50.0, 69.7] versus 55.0%, IQR [42.8, 63.8], Mann-Whitney p = 0.039), the R0/R1 resection rate with or without radiofrequency ablation/stereotactic body radiation therapy was comparable with 54.2% (39/72) of patients in the triplet arm versus 52.7% (39/74) in the doublet arm. At a median follow-up of 26.2 months (IQR [12.8, 40.5]), the median PFS was 11.8 months in the triplet arm versus 13.4 months in the doublet arm (hazard ratio [HR] 0.74, 95% CI [0.50, 1.11], Log-rank p = 0.14). Grade ≥ 3 events were reported in 47.2% (35/74) of patients in the doublet arm and 55.9% (38/68) of patients in the triplet arm. The triplet arm was associated with a higher incidence of grade ≥ 3 neutropenia (44.1% versus 27.0%, p = 0.03) and diarrhea (5.9% versus 0%, p = 0.03). The primary limitations of the study encompass the inherent bias in subjective surgical decisions regarding resection feasibility, as well as the lack of a centralized assessment for ORR and resection. CONCLUSIONS: The combination of cetuximab with FOLFOXIRI did not significantly improve ORR compared to cetuximab plus FOLFOX. Despite achieving an enhanced DpR, this improvement did not translate into improved R0 resection rates or PFS. Moreover, the triplet arm was associated with an increase in treatment-related toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03493048.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Camptotecina , Cetuximab , Neoplasias Colorretais , Fluoruracila , Leucovorina , Neoplasias Hepáticas , Compostos Organoplatínicos , Proteínas Proto-Oncogênicas B-raf , Humanos , Cetuximab/administração & dosagem , Cetuximab/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Masculino , Pessoa de Meia-Idade , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/tratamento farmacológico , Feminino , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Leucovorina/uso terapêutico , Leucovorina/administração & dosagem , Fluoruracila/uso terapêutico , Fluoruracila/administração & dosagem , Compostos Organoplatínicos/uso terapêutico , Compostos Organoplatínicos/administração & dosagem , Proteínas Proto-Oncogênicas B-raf/genética , Idoso , Adulto , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Camptotecina/administração & dosagem , Resultado do Tratamento , Proteínas ras/genética
4.
Neuroendocrinology ; 114(4): 386-399, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38113872

RESUMO

INTRODUCTION: Insulin resistance is widely thought to be a critical feature in type 2 diabetes mellitus (T2DM), and there is significant evidence indicating a higher abundance of insulin receptors in the human cerebellum than cerebrum. However, the specific structural or functional changes in the cerebellum related to T2DM remain unclear, and the association between cerebellar alterations, insulin resistance, cognition, and emotion is yet to be determined. METHODS: We investigated neuropsychological performance, and structural and functional changes in specific cerebellar subregions in 43 T2DM patients with high insulin resistance (T2DM-highIR), 72 T2DM patients with low insulin resistance (T2DM-lowIR), and 50 controls. Furthermore, the correlation and stepwise multiple linear regression analysis were performed. RESULTS: Compared to the controls, T2DM exhibited lower cognitive scores and higher depressive/anxious scores. Furthermore, T2DM-highIR patients showed reduced gray matter volume (GMV) in the right cerebellar lobules VIIb, Crus I/II, and T2DM showed reduced GMV in left lobules I-IV compared to controls. Additionally, functional connectivity decrease was observed between the right lobules I-V and orbital part of the superior frontal gyrus in T2DM-highIR compared to both T2DM-lowIR and controls. Notably, there were negative correlations between the GMV of the lobules VIIb, Crus I/II, and updated homeostatic model assessment of insulin resistance, and positive correlation with executive/visuospatial performance in T2DM patients. CONCLUSIONS: These results suggest that the cerebellar lobules VIIb, Crus I/II, represent vulnerable brain regions in the context of insulin resistance. Overall, this study offers new insights into the neuropathophysiological mechanisms of brain impairment in patients with T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperinsulinismo , Resistência à Insulina , Humanos , Substância Cinzenta/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Cerebelo/diagnóstico por imagem
5.
Pediatr Res ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977796

RESUMO

BACKGROUND: Preterm birth and formula feeding increase the risk of necrotizing enterocolitis (NEC), a gut inflammatory disease known to be associated with gut microbiota (GM) changes in infants. Supplemental bovine colostrum may protect against formula-induced NEC via GM changes. We hypothesised that feeding colostrum before, after, or during formula feeding affects NEC sensitivity via changes to GM. METHODS: Colonic GM (profiled by 16S ribosomal RNA gene amplicon sequencing) was compared in preterm pigs fed colostrum for 4 days, either before, after, or together with formula feeding for 4 days. Correlations between GM and gut parameters were assessed on day 5 or 9. RESULTS: Both exclusive and partial colostrum feeding induced higher GM diversity, lower Enterococcus abundance, and improved intestinal maturation parameters (villus structure, digestive enzyme activities, permeability), relative to exclusive formula feeding (all p < 0.05). Across feeding regimens, Enterococcus abundance was inversely correlated with intestinal maturation parameters. Conversely, there was no correlation between GM changes and early NEC lesions. CONCLUSION: Bovine colostrum inhibits formula-induced Enterococcus overgrowth and gut dysfunctions just after preterm birth but these effects are not causally linked. Optimising diet-related host responses, not GM, may be critical to prevent NEC in preterm newborn pigs and infants. IMPACT: Supplement of bovine colostrum to formula feeding modified the gut microbiota by increasing species diversity and reducing Enterococcus abundance, while concurrently improving intestinal functions in preterm pigs. Diet-related changes to the gut microbiota were not clearly associated with development of necrotizing enterocolitis (NEC) in preterm pigs, suggesting that diet-related gut microbiota effects are not critical for diet-related NEC protection. The study highlights the potential to use bovine colostrum as a supplement to formula feeding for preterm infants lacking human milk.

6.
Pharmacol Res ; 206: 107268, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38908614

RESUMO

Heart failure (HF) has emerged as the most pressing health concerns globally, and extant clinical therapies are accompanied by side effects and patients have a high burden of financial. The protein products of nuclear factor erythroid 2-related factor 2 (Nrf2) target genes have a variety of cardioprotective effects, including antioxidant, metabolic functions and anti-inflammatory. By evaluating established preclinical and clinical research in HF to date, we explored the potential of Nrf2 to exert unique cardioprotective functions as a novel therapeutic receptor for HF. In this review, we generalize the progression, structure, and function of Nrf2 research in the cardiovascular system. The mechanism of action of Nrf2 involved in HF as well as agonists of Nrf2 in natural compounds are summarized. Additionally, we discuss the challenges and implications for future clinical translation and application of pharmacology targeting Nrf2. It's critical to developing new drugs for HF.

7.
Thromb J ; 22(1): 56, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943162

RESUMO

BACKGROUND: Hypercoagulability emerges as a central pathological feature and clinical complication in nephrotic syndrome. Increased platelet activation and aggregability are closely related to hypercoagulability in nephrotic syndrome. Monocyte-platelet aggregates (MPAs) have been proposed to represent a robust biomarker of platelet activation. The aim of this study was to investigate levels of the circulating MPAs and MPAs with the different monocyte subsets to evaluate the association of MPAs with hypercoagulability in nephrotic syndrome. METHODS: Thirty-two patients with nephrotic syndrome were enrolled. In addition, thirty-two healthy age and sex matched adult volunteers served as healthy controls. MPAs were identified by CD14 monocytes positive for CD41a platelets. The classical (CD14 + + CD16-, CM), the intermediate (CD14 + + CD16+, IM) and the non-classical (CD14 + CD16++, NCM) monocytes, as well as subset specific MPAs, were measured by flow cytometry. RESULTS: Patients with nephrotic syndrome showed a higher percentage of circulating MPAs as compared with healthy controls (p < 0.001). The percentages of MPAs with CM, IM, and NCM were higher than those of healthy controls (p = 0.012, p < 0.001 and p < 0.001, respectively). Circulating MPAs showed correlations with hypoalbuminemia (r=-0.85; p < 0.001), hypercholesterolemia (r = 0.54; p < 0.001), fibrinogen (r = 0.70; p < 0.001) and D-dimer (r = 0.37; p = 0.003), but not with hypertriglyceridemia in nephrotic syndrome. The AUC for the prediction of hypercoagulability in nephrotic syndrome using MPAs was 0.79 (95% CI 0.68-0.90, p < 0.001). The sensitivity of MPAs in predicting hypercoagulability was 0.71, and the specificity was 0.78. CONCLUSION: Increased MPAs were correlated with hypercoagulability in nephrotic syndrome. MPAs may serve as a potential biomarker for thrombophilic or hypercoagulable state and provide novel insight into the mechanisms of anticoagulation in nephrotic syndrome.

8.
Sensors (Basel) ; 24(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38610404

RESUMO

Due to the limited semantic information extraction with small objects and difficulty in distinguishing similar targets, it brings great challenges to target detection in remote sensing scenarios, which results in poor detection performance. This paper proposes an improved YOLOv5 remote sensing image target detection algorithm, SEB-YOLO (SPD-Conv + ECSPP + Bi-FPN + YOLOv5). Firstly, the space-to-depth (SPD) layer followed by a non-strided convolution (Conv) layer module (SPD-Conv) was used to reconstruct the backbone network, which retained the global features and reduced the feature loss. Meanwhile, the pooling module with the attention mechanism of the final layer of the backbone network was designed to help the network better identify and locate the target. Furthermore, a bidirectional feature pyramid network (Bi-FPN) with bilinear interpolation upsampling was added to improve bidirectional cross-scale connection and weighted feature fusion. Finally, the decoupled head is introduced to enhance the model convergence and solve the contradiction between the classification task and the regression task. Experimental results on NWPU VHR-10 and RSOD datasets show that the mAP of the proposed algorithm reaches 93.5% and 93.9%respectively, which is 4.0% and 5.3% higher than that of the original YOLOv5l algorithm. The proposed algorithm achieves better detection results for complex remote sensing images.

9.
J Sci Food Agric ; 104(9): 5474-5485, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38391155

RESUMO

BACKGROUND: Campylobacter jejuni (C. jejuni), a widely distributed global foodborne pathogen, primarily linked with contaminated chicken meat, poses a significant health risk. Reducing the abundance of this pathogen in poultry meat is challenging but essential. This study assessed the impact of Lactobacillus-fermented rapeseed meal (LFRM) on broilers exposed to C. jejuni-contaminated litter, evaluating growth performance, Campylobacter levels, and metagenomic profile. RESULTS: By day 35, the litter contamination successfully colonized broilers with Campylobacter spp., particularly C. jejuni. In the grower phase, LFRM improved (P < 0.05) body weight and daily weight gain, resulting in a 9.2% better feed conversion ratio during the pre-challenge period (the period before artificial infection; days 13-20). The LFRM also reduced the C. jejuni concentration in the ceca (P < 0.05), without altering alpha and beta diversity. However, metagenomic data analysis revealed LFRM targeted a reduction in the abundance of C. jejuni biosynthetic pathways of l-tryptophan and l-histidine and gene families associated with transcription and virulence factors while also possibly leading to selected stress-induced resistance mechanisms. CONCLUSION: The study demonstrated that LFRM inclusion improved growth and decreased cecal Campylobacter spp. concentration and the relative abundance of pivotal C. jejuni genes. Performance benefits likely resulted from LFRM metabolites. At the molecular level, LFRM may have reduced C. jejuni colonization, likely by decreasing the abundance of energy transduction and l-histidine and l-tryptophan biosynthesis genes otherwise required for bacterial survival and increased virulence. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Ração Animal , Infecções por Campylobacter , Campylobacter jejuni , Ceco , Galinhas , Fermentação , Histidina , Lactobacillus , Triptofano , Animais , Galinhas/microbiologia , Ração Animal/análise , Campylobacter jejuni/metabolismo , Ceco/microbiologia , Ceco/metabolismo , Triptofano/metabolismo , Lactobacillus/metabolismo , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/prevenção & controle , Infecções por Campylobacter/veterinária , Histidina/metabolismo , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Vias Biossintéticas , Suplementos Nutricionais/análise , Brassica rapa/microbiologia , Brassica rapa/química , Brassica napus/microbiologia
10.
BMC Genomics ; 24(1): 8, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624393

RESUMO

BACKGROUND: Exosomes are nanosized membranous vesicles secreted by various types of cells, which facilitate intercellular communication by transporting bioactive compounds. Exosomes are abundant in biological fluids including semen, and their protein composition and the potential of seminal plasma exosomes (SPEs) as fertility biomarkers were elucidated in humans, however, little information is available regarding buffalo (Bubalus bubalis). Here, we examined protein correlation between spermatozoa, seminal plasma (SP), and SPEs, and we compared and analyzed protein differences between high-motility (H-motility) and low-motility (L-motility) SPEs in buffalo. RESULTS: SPEs were concentrated and purified by ultracentrifugation combined with sucrose density gradient centrifugation, followed by verification using western blotting, nanoparticle tracking analysis, and transmission electron microscopy. Protein composition in spermatozoa, SP and SPEs, and protein difference in H- and L-motility SPEs were identified by LC-MS/MS proteomic analysis and were functionally analyzed through comprehensive bioinformatics. Many SPEs proteins originated from spermatozoa and SP, and nearly one third were also present in spermatozoa and SP. A series of proteins associated with reproductive processes including sperm capacitation, spermatid differentiation, fertilization, sperm-egg recognition, membrane fusion, and acrosome reaction were integrated in a functional network. Comparative proteomic analyses showed 119 down-regulated and 41 up-regulated proteins in L-motility SPEs, compared with H-motility SPEs. Gene Ontology (GO) enrichment of differentially expressed proteins (DEPs) showed that most differential proteins were located in sperm and vesicles, with activities of hydrolase and metalloproteinase, and were involved in sperm-egg recognition, fertilization, single fertilization, and sperm-zona pellucida binding processes, etc. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that differential proteins were mainly involved in the PPRP signaling pathway, calcium signaling pathway, and cAMP signaling pathway, among others. Furthermore, 6 proteins associated with reproduction were validated by parallel reaction monitoring analysis. CONCLUSION: This study provides a comprehensive description of the seminal plasma exosome proteome and may be of use for further screening of biomarkers associated with male infertility.


Assuntos
Exossomos , Sêmen , Animais , Masculino , Humanos , Sêmen/metabolismo , Búfalos , Motilidade dos Espermatozoides , Cromatografia Líquida , Exossomos/metabolismo , Proteômica , Espectrometria de Massas em Tandem , Espermatozoides/metabolismo , Proteoma/metabolismo
11.
Oncologist ; 28(1): e36-e44, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36398872

RESUMO

BACKGROUND: SHR7390 is a novel, selective MEK1/2 inhibitor. Here, we report results from two phase I trials conducted to evaluate the tolerability, safety and antitumor activity of SHR7390 monotherapy for advanced solid tumors and SHR7390 plus camrelizumab for treatment-refractory advanced or metastatic colorectal cancer (CRC). PATIENTS AND METHODS: Patients received SHR7390 alone or combined with fixed-dose camrelizumab (200 mg every 2 weeks) in an accelerated titration scheme to determine the maximum tolerated dose (MTD). A recommended dose for expansion was determined based on the safety and tolerability of the dose-escalation stage. The primary endpoints were dose limiting toxicity (DLT) and MTD. RESULTS: In the SHR7390 monotherapy trial, 16 patients were enrolled. DLTs were reported in the 1.0 mg cohort, and the MTD was 0.75 mg. Grade ≥3 treatment-related adverse events (TRAEs) were recorded in 4 patients (25.0%). No patients achieved objective response. In the SHR7390 combination trial, 22 patients with CRC were enrolled. One DLT was reported in the 0.5 mg cohort and the MTD was not reached. Grade ≥3 TRAEs were observed in 8 patients (36.4%), with the most common being rash (n=4). One grade 5 TRAE (increased intracranial pressure) occurred. Five patients (22.7%) achieved partial response, including one of 3 patients with MSS/MSI-L and BRAF mutant tumors, one of 15 patients with MSS/MSI-L and BRAF wild type tumors, and all 3 patients with MSI-H tumors. CONCLUSIONS: SHR7390 0.5 mg plus camrelizumab showed a manageable safety profile. Preliminary clinical activity was reported regardless of MSI and BRAF status.


Assuntos
Neoplasias , Proteínas Proto-Oncogênicas B-raf , Humanos , Neoplasias/tratamento farmacológico , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
12.
Cell Biol Int ; 47(5): 981-989, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36691872

RESUMO

Leukemia inhibitory factor (LIF) is an important growth factor that supports the culture and maintenance of spermatogonial stem cells (SSCs) by suppressing spontaneous differentiation. Different LIF sequences may lead to differences in function. The protein sequences of buffalo LIF and mouse LIF differed by 65.5% according to MEGA software analysis. The PB-LIF-GFP-Puro vector was constructed, and the CHO-K1 cell line was established. The final LIF protein concentration in the CHO-K1 cell culture medium was approximately 4.268 ng/mL. Here, we report that buffalo LIF effectively maintains the self-renewal of buffalo spermatogonia during culture. Buffalo spermatogonia were cultured in conditioned medium containing no LIF (0 ng/mL), mouse LIF (1 ng/mL), mouse LIF (10 ng/mL), or buffalo LIF (1 ng/mL). Furthermore, the effects of mouse LIF and buffalo LIF culture on the maintenance of buffalo spermatogonia were determined by analyzing cell colony formation, quantitative real-time polymerase chain reaction, cell immunofluorescence, and cell counting. The buffalo LIF (1 ng/mL) group showed similar maintenance of the proliferation of buffalo spermatogonia to that in the mouse LIF (10 ng/mL) group. These results demonstrated that the proliferation of buffalo spermatogonia can be maintained in vitro by adding a low dose of buffalo LIF. This study provides a foundation for the further optimization of in vitro buffalo SSC culture systems.


Assuntos
Espermatogônias , Células-Tronco , Animais , Masculino , Camundongos , Fator Inibidor de Leucemia/metabolismo , Fator Inibidor de Leucemia/farmacologia , Meios de Cultura , Diferenciação Celular , Células Cultivadas
13.
Inorg Chem ; 62(44): 18209-18218, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37861751

RESUMO

A luminescent Tb-MOF with excellent stability and dual-emitting properties was constructed with an amide-functionalized tetracarboxylate ligand. Tb-MOFs were initially assembled on one-dimensional Tb3+ chains, then formed a two-dimensional double-decker layer through the synergistic linking of organic ligands and bridging formic acid anions, and further fabricated the final three-dimensional structure through the connection of the organic ligands. Powder X-ray diffraction experiments revealed that Tb-MOFs not only exhibited excellent stability in water but also maintained structural integrity in the pH range of 2-12. Importantly, this Tb-MOF provided the first example of a metal-organic framework (MOF)-based luminescence sensor that can simultaneously detect two acid amino acids (aspartic and glutamic acids) through a turn-off sensing mechanism and two basic amino acids (lysine and arginine acids) through unusual turn-on and turn-off-on sensing mechanisms. Moreover, high sensitivity, low detection limit, and excellent recyclability of this sensor endow Tb-MOFs with great potential as a highly efficient amino acid fluorescence sensor in chemical detection and biological environments.

14.
BMC Infect Dis ; 23(1): 522, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37558992

RESUMO

BACKGROUND: Septicemia that leads to ocular involvement mostly presents as endophthalmitis or panophthalmitis. Contrarily, septicemia without intraocular involvement, known as hematogenous orbital cellulitis (HOC), involves only the orbit and is an extremely rare complication of septicemia and a rare type of orbital cellulitis. CASE PRESENTATION: Four male patients with septicemia presented with orbital involvement without intraocular infection were described in this study. They were 22 (case 1), 15 (case 2), 79 (case 3), and 30 (case 4) years old, with a mean age of 29.75 years. All patients were immunocompromised except for case 2. Cases 1 and 3 had a history of steroid use, whereas case 4 was in a post-chemotherapy myelosuppression phase. Septicemia in case 1 was community-acquired, cases 3 and 4 were hospital-acquired, and case 2 was secondary to acne squeezing. Blood cultures from cases 1, 2, and 3 were positive for Candida albicans, methicillin-resistant Staphylococcus aureus, and Klebsiella pneumoniae, respectively. Case 4 had negative cultures; however, next-generation sequencing reported the presence of Enterococcus faecalis and Rhizopus oryzae. Case 1 had right eye involvement, and both eyes were involved in the other three cases. According to Chandler's classification, case 1 was type 2, case 2 was type 2 (OD) and type 4 (OS), and cases 3 and 4 were type 1 orbital infections. All patients had eyelids erythema, and cases 1 and 2 had mildly decreased visual acuity, proptosis, and painful and restricted ocular motility. Hospital stays ranged from 13 to 43 days (mean, 24 days). All patients received systemic antibiotic therapy based on drug sensitivity and next-generation sequencing results, in combination with multidisciplinary treatment, resulting in complete recovery of ocular and systemic signs and symptoms; no ocular surgical interventions were performed. Extraocular muscle palsy was the last symptom to resolve. CONCLUSION: HOC is predominantly seen in immunocompromised individuals with a high proportion of hospital-acquired infections and positive cultures for pathogens. Infection control using systemic antibiotics targeted at the causative organism guarantees a favorable prognosis.


Assuntos
Infecções Oculares , Staphylococcus aureus Resistente à Meticilina , Celulite Orbitária , Sepse , Adulto , Humanos , Masculino , Antibacterianos/uso terapêutico , Infecções Oculares/tratamento farmacológico , Órbita , Celulite Orbitária/tratamento farmacológico , Sepse/complicações , Sepse/diagnóstico , Sepse/tratamento farmacológico , Adolescente , Adulto Jovem , Idoso
15.
J Phys Chem A ; 127(36): 7510-7517, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37647565

RESUMO

The Stone-Wales defect is a well-known and significant defective structure in carbon materials, impacting their mechanical, chemical, and electronic properties. Recently, a novel metal-carbon nanomaterial named Volleyballene was discovered, characterized by a C-C bond bridging two carbon pentagons. Using first-principles calculations, a stable Stone-Wales-defective counterpart of Volleyballene, exhibiting Th symmetry, has been proposed by rotating the C-C bond by 90°. Although its binding energy per atom is slightly higher than that of Volleyballene (ΔEb = 0.009 eV/atom), implying marginally lower structural stability, it can maintain its bond structure until the effective temperature reaches about 1500 K, indicating greater thermodynamic stability. Additionally, its highest vibration frequency is 1346.2 cm-1, indicating a strong chemical bond strength. A theoretical analysis of the Sc20C60 + Sc20C60 binary systems highlights that the stable building block may be applied in potential nanoassemblies.

16.
Sensors (Basel) ; 23(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37960366

RESUMO

Due to high maneuverability as well as hardware limitations of Unmanned Aerial Vehicle (UAV) platforms, tracking targets in UAV views often encounter challenges such as low resolution, fast motion, and background interference, which make it difficult to strike a compatibility between performance and efficiency. Based on the Siamese network framework, this paper proposes a novel UAV tracking algorithm, SiamHSFT, aiming to achieve a balance between tracking robustness and real-time computation. Firstly, by combining CBAM attention and downward information interaction in the feature enhancement module, the provided method merges high-level and low-level feature maps to prevent the loss of information when dealing with small targets. Secondly, it focuses on both long and short spatial intervals within the affinity in the interlaced sparse attention module, thereby enhancing the utilization of global context and prioritizing crucial information in feature extraction. Lastly, the Transformer's encoder is optimized with a modulation enhancement layer, which integrates triplet attention to enhance inter-layer dependencies and improve target discrimination. Experimental results demonstrate SiamHSFT's excellent performance across diverse datasets, including UAV123, UAV20L, UAV123@10fps, and DTB70. Notably, it performs better in fast motion and dynamic blurring scenarios. Meanwhile, it maintains an average tracking speed of 126.7 fps across all datasets, meeting real-time tracking requirements.

17.
Sheng Li Xue Bao ; 75(1): 99-107, 2023 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-36859839

RESUMO

Silent information regulator 1 (SIRT1) is one of the seven mammalian proteins of the sirtuin family of NAD+-dependent deacetylases. SIRT1 plays a pivotal role in neuroprotection and ongoing research has uncovered a mechanism by which SIRT1 may exert a neuroprotective effect on Alzheimer's disease (AD). Growing evidence demonstrates that SIRT1 regulates many pathological processes including amyloid-ß precursor protein (APP) processing, neuroinflammation, neurodegeneration, and mitochondrial dysfunction. SIRT1 has recently received enormous attention, and pharmacological or transgenic approaches to activate the sirtuin pathway have shown promising results in the experimental models of AD. In the present review, we delineate the role of SIRT1 in AD from a disease-centered perspective and provides an up-to-date overview of the SIRT1 modulators and their potential as effective therapeutics in AD.


Assuntos
Doença de Alzheimer , Sirtuínas , Animais , Precursor de Proteína beta-Amiloide , Animais Geneticamente Modificados , Sirtuína 1 , Humanos
18.
Int Wound J ; 20(5): 1609-1621, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36372913

RESUMO

Diabetic Foot in Primary and Tertiary (DEFINITE) Care is an inter-institutional and multi-disciplinary team (MDT) health systems innovation programme at a healthcare cluster in Singapore. We aim to achieve coordinated MDT care across primary and tertiary care for patients with diabetic foot ulcers (DFU), within our public healthcare cluster - an integrated network of seven primary care polyclinics and two acute care tertiary hospitals (1700-bed and 800-bed) with a total catchment population of 2.2 million residents. Results from prospective DEFINITE Care is referenced against a retrospective 2013-2017 cohort, which was previously published. Cardiovascular profile of the study population is compared against the same population's profile in the preceding 12 months. Between June 2020 and December 2021, there were 3475 unique patients with DFU with mean age at 65.9 years, 61.2% male, mean baseline HbA1c at 8.3% with mean diabetes duration at 13.3 years, mean diabetes complication severity index (DCSI) at 5.6 and mean Charlson Comorbidity Index (CCI) at 6.8. In the 12-months preceding enrolment to DEFINITE Care, 35.5% had surgical foot debridement, 21.2% had minor lower extremity amputation (LEA), 7.5% had major LEA whilst 16.8% had revascularisation procedures. At 18-months after the implementation of DEFINITE Care programme, the absolute minor and major amputation rates were 8.7% (n = 302) and 5.1% (n = 176), respectively, equating to a minor and major LEA per 100000 population at 13.7 and 8.0, respectively. This represents an 80% reduction in minor amputation rates (P < .001) and a 35% reduction in major amputation rates (P = .005) when referenced against a retrospective 2013-2017 cohort, which had minor and major LEA per 100000 population at 68.9 and 12.4, respectively. As compared to the preceding 12 months, there was also a significant improvement in cardiovascular profile (glycemic and lipid control) within the DEFINITE population, with improved mean HbAc1 (7.9% from 8.4%, P < .001), low-density lipoprotein (LDL) levels (2.1 mmol/L from 2.2, P < .001), total cholesterol (3.9 mmol/L from 4.1, P < .001) and triglycerides levels (1.6 mmol/L from 1.8, P = .002). Multivariate analysis revealed a history of minor amputation in the preceding 12 months to be an independent predictor for major and minor amputation within the study period of 18 months (Hazard Ratio 3.4 and 1.8, respectively, P < .001). In conclusion, within DEFINITE care, 18-month data showed a significant reduction of minor and major LEA rates, with improved medical optimisation and cardiovascular profile within the study population.


Assuntos
Diabetes Mellitus , Pé Diabético , Idoso , Feminino , Humanos , Masculino , Estudos de Coortes , Pé Diabético/cirurgia , Serviços de Saúde , Estudos Prospectivos , Estudos Retrospectivos , Atenção Terciária à Saúde
19.
Angew Chem Int Ed Engl ; 62(11): e202216950, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36625196

RESUMO

To conquer the bottleneck of sluggish kinetics in cathodic oxygen reduction reaction (ORR) of metal-air batteries, catalysts with dual-active centers have stood out. Here, a "pre-division metal clusters" strategy is firstly conceived to fabricate a N,S-dual doped honeycomb-like carbon matrix inlaid with CoN4 sites and wrapped Co2 P nanoclusters as dual-active centers (Co2 P/CoN4 @NSC-500). A crystalline {CoII 2 } coordination cluster divided by periphery second organic layers is well-designed to realize delocalized dispersion before calcination. The optimal Co2 P/CoN4 @NSC-500 executes excellent 4e- ORR activity surpassing the benchmark Pt/C. Theoretical calculation results reveal that the CoN4 sites and Co2 P nanoclusters can synergistically quicken the formation of *OOH on Co sites. The rechargeable Zn-air battery (ZAB) assembled by Co2 P/CoN4 @NSC-500 delivers ultralong cycling stability over 1742 hours (3484 cycles) under 5 mA cm-2 and can light up a 2.4 V LED bulb for ≈264 hours, evidencing the promising practical application potentials in portable devices.

20.
Gut ; 71(7): 1340-1349, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34489309

RESUMO

OBJECTIVE: Circulating tumour DNA (ctDNA) sequencing is increasingly used in the clinical management of patients with colorectal cancer. However, the genomic heterogeneity in ctDNA during treatments and its impact on clinical outcomes remain largely unknown. DESIGN: We conducted a prospective cohort study (NCT04228614) of 171 patients with unresectable metastatic colorectal cancer (mCRC) who underwent first-line treatment and prospectively collected blood samples with or without tumour samples from patients at baseline and sequentially until disease progression or last follow-up. RESULTS: The RAS/BRAF alterations in paired baseline tissue and plasma samples from 63 patients displayed a favourable concordance (81.0%, 51/63). After a period of first-line treatment (median time between baseline and last liquid biopsy, 4.67 months), 42.6% (26/61) of RAS-mutant patients showed RAS clearance and 50.0% (5/10) of BRAF-mutant patients showed BRAF clearance, while 3.6% (3/84) and 0.7% (1/135) of patients showed new RAS or BRAF mutations in ctDNA. Patients with plasma RAS/BRAF clearance showed similar progression-free survival (PFS) and overall survival (OS) with patients who remained RAS/BRAF wild-type, while much better outcomes than those who remained RAS/BRAF mutant. Patients who gained new RAS/BRAF mutations showed similar prognosis as those who maintained RAS/BRAF mutations, and shorter PFS and OS than those who remained RAS/BRAF wild-type. CONCLUSION: This prospective, serial and large-scale ctDNA profiling study reveals the temporal heterogeneity of mCRC-related somatic variants, which should be given special attention in clinical practice, as evidenced by the finding that the shift in plasma RAS/BRAF mutational status can yield a drastic change in survival outcomes.


Assuntos
DNA Tumoral Circulante , Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , DNA Tumoral Circulante/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Genômica , Humanos , Mutação , Estudos Prospectivos , Proteínas Proto-Oncogênicas B-raf/genética
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