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1.
Nat Commun ;15(1): 3737, 2024 May 03.
ArtigoemInglês |MEDLINE | ID: mdl-38702313

RESUMO

Twisted bilayer graphene (tBLG) provides a fascinating platform for engineering flat bands and inducing correlated phenomena. By designing the stacking architecture of graphene layers, twisted multilayer graphene can exhibit different symmetries with rich tunability. For example, in twisted monolayer-bilayer graphene (tMBG) which breaks the C2z symmetry, transport measurements reveal an asymmetric phase diagram under an out-of-plane electric field, exhibiting correlated insulating state and ferromagnetic state respectively when reversing the field direction. Revealing how the electronic structure evolves with electric field is critical for providing a better understanding of such asymmetric field-tunable properties. Here we report the experimental observation of field-tunable dichotomic electronic structure of tMBG by nanospot angle-resolved photoemission spectroscopy (NanoARPES) with operando gating. Interestingly, selective enhancement of the relative spectral weight contributions from monolayer and bilayer graphene is observed when switching the polarity of the bias voltage. Combining experimental results with theoretical calculations, the origin of such field-tunable electronic structure, resembling either tBLG or twisted double-bilayer graphene (tDBG), is attributed to the selectively enhanced contribution from different stacking graphene layers with a strong electron-hole asymmetry. Our work provides electronic structure insights for understanding the rich field-tunable physics of tMBG.

2.
Front Plant Sci ;15: 1381071, 2024.
ArtigoemInglês |MEDLINE | ID: mdl-38699538

RESUMO

Introduction: The biosynthesis of secondary metabolites like anthocyanins is often governed by metabolic gene clusters (MGCs) in the plant ancestral genome. However, the existence of gene clusters specifically regulating anthocyanin accumulation in certain organs is not well understood. Methods and results: In this study, we identify MGCs linked to the coloration of cotton reproductive organs, such as petals, spots, and fibers. Through genetic analysis and map-based cloning, we pinpointed key genes on chromosome A07, such as PCC/GhTT19, which is involved in anthocyanin transport, and GbBM and GhTT2-3A, which are associated with the regulation of anthocyanin and proanthocyanidin biosynthesis. Our results demonstrate the coordinated control of anthocyanin and proanthocyanidin pathways, highlighting the evolutionary significance of MGCs in plant adaptation. The conservation of these clusters in cotton chromosome A07 across species underscores their importance in reproductive development and color variation. Our study sheds light on the complex biosynthesis and transport mechanisms for plant pigments, emphasizing the role of transcription factors and transport proteins in pigment accumulation. Discussion: This research offers insights into the genetic basis of color variation in cotton reproductive organs and the potential of MGCs to enhance our comprehension of plant secondary metabolism.

3.
Nat Commun ;15(1): 3669, 2024 Apr 30.
ArtigoemInglês |MEDLINE | ID: mdl-38693119

RESUMO

Oncolytic viruses (OVs) show promise as a cancer treatment by selectively replicating in tumor cells and promoting antitumor immunity. However, the current immunogenicity induced by OVs for tumor treatment is relatively weak, necessitating a thorough investigation of the mechanisms underlying its induction of antitumor immunity. Here, we show that HSV-1-based OVs (oHSVs) trigger ZBP1-mediated PANoptosis (a unique innate immune inflammatory cell death modality), resulting in augmented antitumor immune effects. Mechanistically, oHSV enhances the expression of interferon-stimulated genes, leading to the accumulation of endogenous Z-RNA and subsequent activation of ZBP1. To further enhance the antitumor potential of oHSV, we conduct a screening and identify Fusobacterium nucleatum outer membrane vesicle (Fn-OMV) that can increase the expression of PANoptosis execution proteins. The combination of Fn-OMV and oHSV demonstrates potent antitumor immunogenicity. Taken together, our study provides a deeper understanding of oHSV-induced antitumor immunity, and demonstrates a promising strategy that combines oHSV with Fn-OMV.


Assuntos
Fusobacterium nucleatum, Herpesvirus Humano 1, Terapia Viral Oncolítica, Vírus Oncolíticos, Proteínas de Ligação a RNA, Herpesvirus Humano 1/imunologia, Herpesvirus Humano 1/genética, Vírus Oncolíticos/genética, Vírus Oncolíticos/imunologia, Animais, Humanos, Terapia Viral Oncolítica/métodos, Camundongos, Proteínas de Ligação a RNA/genética, Proteínas de Ligação a RNA/metabolismo, Proteínas de Ligação a RNA/imunologia, Linhagem Celular Tumoral, Fusobacterium nucleatum/imunologia, Neoplasias/terapia, Neoplasias/imunologia, Feminino, Imunidade Inata, Camundongos Endogâmicos BALB C
4.
Sci Transl Med ;16(745): eadh1763, 2024 May.
ArtigoemInglês |MEDLINE | ID: mdl-38691618

RESUMO

An abdominal aortic aneurysm (AAA) is a life-threatening cardiovascular disease. We identified plasma insulin-like growth factor 1 (IGF1) as an independent risk factor in patients with AAA by correlating plasma IGF1 with risk. Smooth muscle cell- or fibroblast-specific knockout of Igf1r, the gene encoding the IGF1 receptor (IGF1R), attenuated AAA formation in two mouse models of AAA induced by angiotensin II infusion or CaCl2 treatment. IGF1R was activated in aortic aneurysm samples from human patients and mice with AAA. Systemic administration of IGF1C, a peptide fragment of IGF1, 2 weeks after disease development inhibited AAA progression in mice. Decreased AAA formation was linked to competitive inhibition of IGF1 binding to its receptor by IGF1C and modulation of downstream alpha serine/threonine protein kinase (AKT)/mammalian target of rapamycin signaling. Localized application of an IGF1C-loaded hydrogel was developed to reduce the side effects observed after systemic administration of IGF1C or IGF1R antagonists in the CaCl2-induced AAA mouse model. The inhibitory effect of the IGF1C-loaded hydrogel administered at disease onset on AAA formation was further evaluated in a guinea pig-to-rat xenograft model and in a sheep-to-minipig xenograft model of AAA formation. The therapeutic efficacy of IGF1C for treating AAA was tested through extravascular delivery in the sheep-to-minipig model with AAA established for 2 weeks. Percutaneous injection of the IGF1C-loaded hydrogel around the AAA resulted in improved vessel flow dynamics in the minipig aorta. These findings suggest that extravascular administration of IGF1R antagonists may have translational potential for treating AAA.


Assuntos
Aneurisma da Aorta Abdominal, Modelos Animais de Doenças, Fator de Crescimento Insulin-Like I, Receptor IGF Tipo 1, Animais, Receptor IGF Tipo 1/metabolismo, Receptor IGF Tipo 1/antagonistas & inibidores, Humanos, Aneurisma da Aorta Abdominal/patologia, Aneurisma da Aorta Abdominal/tratamento farmacológico, Aneurisma da Aorta Abdominal/metabolismo, Aneurisma da Aorta Abdominal/prevenção & controle, Fator de Crescimento Insulin-Like I/metabolismo, Masculino, Suínos, Camundongos, Transdução de Sinais/efeitos dos fármacos, Camundongos Endogâmicos C57BL, Ratos
5.
BMC Cancer ;24(1): 568, 2024 May 07.
ArtigoemInglês |MEDLINE | ID: mdl-38714979

RESUMO

PURPOSE: The index composed of preoperative lymphocytes, albumin, and neutrophils (LANR), a new composite score based on inflammatory response and nutritional status, has been reported to be associated with the prognosis of multiple types of cancer, but the role of LANR in the prognosis of resectable pancreatic ductal adenocarcinoma (PDAC) has not yet been elucidated. PATIENTS AND METHODS: The data of 142 patients with PDAC who underwent radical resection in the Affiliated Hospital of Jiangnan University from January 2015 to December 2018 were retrospectively analyzed. Receiver Operating Characteristic (ROC) curves were generated to determine the optimal cut-off values for these parameters, as well as the sensitivity and specificity of LANR in predicting survival. The Kaplan-Meier method was used to draw the survival curves. Log rank test was used for univariate analysis, and Cox proportional hazards regression model was used for multivariate analysis.  RESULTS: The optimal cut-off value of LANR was 18.145, and a low preoperative LANR was significantly correlated with the location of the tumor (p = 0.047). Multivariate analysis showed that tumor differentiation degree (HR:2.357, 95%CI:1.388-4.003,p = 0.002), lymph node metastasis (HR:1.755, 95%CI: 1.115-2.763, p = 0.015), TNM stage (HR:4.686, 95%CI: 2.958-7.425, p < 0.001), preoperative cancer antigen 19 - 9 levels (HR:1.001, 95%CI: 1.000-1.001, p < 0.001) and preoperative LANR (HR:0.221, 95%CI: 0.111-0.441, p < 0.001) were independent risk factors for a poor prognosis in patients undergoing radical resection of PDAC. CONCLUSION: This study found that preoperative LANR can be used to assess the prognosis of radical resection in patients with PDAC; those with low preoperative LANR had a worse outcome.


Assuntos
Carcinoma Ductal Pancreático, Linfócitos, Neutrófilos, Neoplasias Pancreáticas, Adulto, Idoso, Feminino, Humanos, Masculino, Pessoa de Meia-Idade, Biomarcadores Tumorais, Carcinoma Ductal Pancreático/cirurgia, Carcinoma Ductal Pancreático/patologia, Carcinoma Ductal Pancreático/mortalidade, Estimativa de Kaplan-Meier, Linfócitos/patologia, Neutrófilos/patologia, Neoplasias Pancreáticas/cirurgia, Neoplasias Pancreáticas/patologia, Neoplasias Pancreáticas/mortalidade, Período Pré-Operatório, Prognóstico, Estudos Retrospectivos, Curva ROC, Albumina Sérica/análise, Albumina Sérica/metabolismo, Idoso de 80 Anos ou mais
6.
Sex Med Rev ;2024 May 08.
ArtigoemInglês |MEDLINE | ID: mdl-38719619

RESUMO

INTRODUCTION: Androgens play important roles in regulating the growth and development of the male reproductive system and maintaining libido and erectile function. The specific mechanisms by which androgen deficiency leads to erectile dysfunction (ED) are not yet fully understood. OBJECTIVES: To understand the mechanisms and treatment of androgen deficiency-related ED. METHODS: A literature search in the past 10 years was conducted in PubMed and Google Scholar to determine the effects of androgen deficiency on erectile function and the treatment of androgen deficiency. RESULTS: Androgen deficiency can be caused by hypothalamic-pituitary lesions and injuries, testicular-related diseases and injuries, endocrine and metabolic disorders, the side effects of medication, and age. Androgen deficiency can lead to ED by inhibiting the NOS/NO/cGMP pathway (nitric oxide synthase/nitric oxide/cyclic guanosine monophosphate) and altering the expression of ion channel proteins, as well as by inducing oxidative stress, death, and fibrosis in penile corpus cavernosum cells. Testosterone replacement therapy is effective at improving the serum testosterone levels and erectile function in patients with androgen deficiency. For patients who need to maintain a low androgenic state, erectile function can be improved by lifestyle changes, treatment with phosphodiesterase type 5 inhibitors, low-intensity extracorporeal shock wave therapy, and stem cell therapy. CONCLUSIONS: Androgen deficiency can affect the structure and function of the penile corpus cavernosum, leading to ED. Areas of further study include how androgen replacement therapy can improve erectile function and how to improve the maintenance of erectile function in patients with hypoandrogenic status.

7.
Adv Mater ;: e2403570, 2024 May 06.
ArtigoemInglês |MEDLINE | ID: mdl-38710097

RESUMO

A formidable challenge to achieve the practical applications of rechargeable lithium (Li) metal batteries (RLMBs) is to suppress the uncontrollable growth of Li dendrites. One of the most effective solutions is to fabricate Li metal anodes with specific crystal plane, but still lack of a simple and high-efficient approach. Herein, a facile and controllable way for the scalable customization of polished Li metal anodes with highly preferred (110) and (200) crystallographic orientation (donating as polished Li(110) and polished Li(200), respectively) by regulating the times of accumulative roll bonding, is reported. According to the inherent characteristics of polished Li(110)/Li(200), the influence of Li atomic structure on the electrochemical performance of RLMBs is deeply elucidated by combining theoretical calculations with relative experimental proofs. In particular, a polished Li(110) crystal plane is demonstrated to induce Li+ uniform deposition, promoting the formation of flat and dense Li deposits. Impressively, the polished Li(110)||LiFePO4 full cells exhibit unprecedented cycling stability with 10 000 cycles at 10 C almost without capacity degradation, indicating the great potential application prospect of such textured Li metal. More valuably, this work provides an important reference for low-cost, continued, and large-scale production of Li metal anodes with highly preferred crystal orientation through roll-to-roll manufacturability.

8.
ArtigoemInglês |MEDLINE | ID: mdl-38700489

RESUMO

OBJECTIVES: The aim of this study was to evaluating the performance of the automated insulin delivery (AID) in adolescents, and children with type 1 diabetes (T1D) during physical activity. METHODS: Relevant studies were searched electronically in the Cochrane Library, PubMed, and Embase utilizing the key words "Child", "Insulin Infusion Systems", and "Diabetes Mellitus" from inception to 17th March 2024 to evaluate the performance of the AID in adolescents, and children with T1D during physical activity. RESULTS: Twelve studies involving 514 patients were identified. AID did not show a beneficial effect on duration of hypoglycemia<70 mg/dL during study period (p>0.05; I 2=96 %) and during the physical activity (p>0.99). Percentage of sensor glucose values in TIR was higher in AID than the non-AID pumps during study period (p<0.001; I 2=94 %). The duration of hyperglycemic time was significantly decreased in AID group compared to the non-AID pumps group during study period (p<0.05; I 2>50 %). CONCLUSIONS: AID improved TIR and decreased the duration of hyperglycemic time, but did not appear to have a significant beneficial effect on the already low post-exercise duration of hypoglycemia achievable by open loop or sensor-augmented pumps in adolescents and children with T1D during physical activity; further research is needed to confirm the beneficial effect of AID on duration of hypoglycemia.

9.
Molecules ;29(9)2024 Apr 23.
ArtigoemInglês |MEDLINE | ID: mdl-38731413

RESUMO

Ultraviolet radiation can heighten tyrosinase activity, stimulate melanocyte production, impede the metabolism of numerous melanocytes, and result in the accumulation of plaques on the skin surface. α-Arbutin, a bioactive substance extracted from the arbutin plant, has been widely used for skin whitening. In this study, the whitening effect of α-arbutin by inhibiting tyrosinase activity and alleviating the photoaging effect induced by UVB are investigated. The results indicate that α-arbutin can inhibit skin inflammation, and its effectiveness is positively correlated with concentration. Moreover, α-arbutin can reduce the skin epidermal thickness, decrease the number of inflammatory cells, and down-regulate the expression levels of IL-1ß, IL-6 and TNF-α, which are inflammatory factors. It also promotes the expression of COL-1 collagen, thus playing an important role in anti-inflammatory action. Network pharmacology, metabolomics and transcriptomics further confirm that α-arbutin is related to the L-tyrosine metabolic pathway and may interfere with various signaling pathways related to melanin and other photoaging by regulating metabolic changes. Therefore, α-arbutin has a potential inhibitory effect on UVB-induced photoaging and possesses a whitening effect as a cosmetic compound.


Assuntos
Arbutina, Envelhecimento da Pele, Raios Ultravioleta, Arbutina/farmacologia, Raios Ultravioleta/efeitos adversos, Animais, Envelhecimento da Pele/efeitos dos fármacos, Envelhecimento da Pele/efeitos da radiação, Camundongos, Monofenol Mono-Oxigenase/metabolismo, Monofenol Mono-Oxigenase/antagonistas & inibidores, Humanos, Pele/efeitos da radiação, Pele/efeitos dos fármacos, Pele/metabolismo, Pele/patologia
10.
J Coll Physicians Surg Pak ;34(5): 527-532, 2024 May.
ArtigoemInglês |MEDLINE | ID: mdl-38720211

RESUMO

OBJECTIVE: To develop an intervention based on Notch-1 signalling pathway blockade by investigating the potential application of the neurogenic locus notch homologue protein 1(Notch-1) signalling pathway as a key regulator of chronic inflammation and adipogenesis in the treatment of hepatic insulin resistance (HIR). STUDY DESIGN: Experimental study. Place and Duration of the Study: Animal Laboratory of the Fourth Hospital of Hebei Medical University, Shijiazhuang, China, from April 2021 to June 2022. METHODOLOGY: HIR models were established in Notch-1WT and Notch-1MAC-KO mice by high fat diet (HFD) for 16 weeks. Haematoxylin and eosin (HE) staining and oil red O (ORO) staining were used to detect inflammatory infiltration and lipid accumulation in each group. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of TNF-α and IL-6. Free fatty acid (FFA) and total cholesterol (TC) were measured with relevant kits. Moreover, real-time quantitative polymerase chain reaction (PCR) was performed to detect the relative expressions of F4/80, Mcp1, and CD11b in hepatic tissues. Mass spectrometry was used to analyse the levels of triglyceride (TG), diacylglycerol (DAG) and conformite europeenne (CE) in liver tissue. Western blotting was used to detect the expression of related proteins. RESULTS: Specific knockdown of Notch-1 in macrophages decreases the relative fluorescence intensity of CD68 and attenuates inflammatory infiltration and lipid degeneration. There was no difference in plasma levels of FFA and TG. Specific knockdown of Notch-1 in macrophages decreases the expression of F4/80, Mcp1, and CD11b, as well as the levels of TG, DAG, CE, IL-6, and TNF-α. CONCLUSION: Specific knockout of Notch-1 in macrophages may reduce HIR by inhibiting the IRE1α-XBP1 signalling pathway. KEY WORDS: Hepatic insulin resistance, Macrophages, Notch-1, IRE1α, XBP1.


Assuntos
Dieta Hiperlipídica, Resistência à Insulina, Macrófagos, Camundongos Knockout, Proteínas Serina-Treonina Quinases, Receptor Notch1, Transdução de Sinais, Animais, Camundongos, Modelos Animais de Doenças, Endorribonucleases/metabolismo, Endorribonucleases/genética, Resistência à Insulina/fisiologia, Fígado/metabolismo, Macrófagos/metabolismo, Proteínas Serina-Treonina Quinases/genética, Proteínas Serina-Treonina Quinases/metabolismo, Receptor Notch1/metabolismo, Receptor Notch1/genética, Proteína 1 de Ligação a X-Box/metabolismo, Proteína 1 de Ligação a X-Box/genética
11.
Trials ;25(1): 348, 2024 May 28.
ArtigoemInglês |MEDLINE | ID: mdl-38807239

RESUMO

BACKGROUND: Embryo implantation remains a critical barrier in assisted reproductive technologies. One of the main causes of unsuccessful embryo implantation is window of implantation (WOI) displacement, particularly in patients with recurrent implantation failure (RIF). Therefore, a reliable diagnostic tool for identifying the optimal WOI is essential. Previous data has suggested that a novel RNA-Seq-based endometrial receptivity testing (ERT) can diagnose WOI, guide personalized embryo transfer (pET), and improve pregnancy outcomes in patients with RIF compared to standard embryo transfer (sET). However, there is still a lack of evidence from randomized controlled trials (RCT) with sufficient power to determine whether pET based on ERT can increase the rate of live births as the primary outcome. METHODS: This trial is a prospective, single-blind, parallel-group RCT (1:1 ratio of pET versus sET). Infertile women with RIF who intend to undergo frozen-thawed embryo transfer (FET) after preimplantation genetic testing for aneuploidy (PGT-A) with the availability of at least one euploid blastocyst for transfer will be enrolled and assigned into two parallel groups randomly. Participants in the intervention group will undergo ERT and then pET based on the results of ERT, while those in the control group will undergo sET. The primary outcome is live birth rate. DISCUSSION: The findings of this study will provide evidence for the effect of pET guided by ERT on pregnancy outcomes in patients with RIF. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2100049041. Registered on 20 July 2021.


Assuntos
Implantação do Embrião, Transferência Embrionária, Endométrio, Nascido Vivo, Ensaios Clínicos Controlados Aleatórios como Assunto, Humanos, Feminino, Gravidez, Transferência Embrionária/métodos, Endométrio/fisiopatologia, Estudos Prospectivos, Método Simples-Cego, Infertilidade Feminina/terapia, Infertilidade Feminina/fisiopatologia, Adulto, Taxa de Gravidez, Resultado do Tratamento, China, Valor Preditivo dos Testes
12.
Environ Res ;255: 119148, 2024 May 14.
ArtigoemInglês |MEDLINE | ID: mdl-38754607

RESUMO

BACKGROUND: The evidence of interactive effect of the toxic metal (TM) mixture and apolipoprotein E (APOE) ε4 gene on cognitive impairment in older adults is scarce. We aimed to explore whether the associations of single TMs and their mixture with cognitive impairment depend on APOE ε4 in Chinese community-dwelling older people. METHODS: A total of 1148 older adults from a subset of the baseline survey of a cohort study were included. Blood arsenic (As), cadmium (Cd), lead (Pb), strontium (Sr), and vanadium (V) were detected by inductively coupled plasma mass spectrometry. APOE gene (rs429358, rs7412) polymorphisms were analyzed by the Polymerase Chain Reaction instrument. Mixed effects logistic regression was applied to estimate the relationships of single TMs and APOE genotype with cognitive impairment. Weighted quantile sum (WQS) and Bayesian kernel machine regression (BKMR) models were performed to examine joint impacts of the TM mixture, as well as the interaction of the TM mixture with APOE ε4 genotype on cognitive impairment. RESULTS: Pb displayed a significant linear association with an increased odds of cognitive impairment after adjustment for covariates (Ptrend = 0.045). While APOE genotype did not show a significant correlation with cognitive impairment. WQS showed that the TM mixture was associated with an increased risk of cognitive impairment by 31.0% (OR=1.31, 95% CI: 0.92, 1.87) while no significance was found. BKMR exhibited a significant linear association between the TM mixture and cognitive impairment. Moreover, both WQS and BKMR indicated that Pb contributed the most to cognitive impairment within the mixture. Significant interactions of Pb or the TM mixture and APOE genotype on cognitive impairment were observed, contributing to 38.1% and 38.2% of total effects, respectively. CONCLUSIONS: APOE ε4 allele amplifies the associations of single Pb or the TM mixture with cognitive impairment. These findings may help to develop precision prevention.

13.
Med Mycol ;62(5)2024 May 03.
ArtigoemInglês |MEDLINE | ID: mdl-38692846

RESUMO

Candida albicans is a pathogenic fungus that undergoes morphological transitions between hyphal and yeast forms, adapting to diverse environmental stimuli and exhibiting distinct virulence. Existing research works on antifungal blue light (ABL) therapy have either focused solely on hyphae or neglected to differentiate between morphologies, obscuring potential differential effects. To address this gap, we established a novel dataset of 150 C. albicans-infected mouse skin tissue slice images with meticulously annotated hyphae and yeast. Eleven representative convolutional neural networks were trained and evaluated on this dataset using seven metrics to identify the optimal model for segmenting hyphae and yeast in original high pixel size images. Leveraging the segmentation results, we analyzed the differential impact of blue light on the invasion depth and density of both morphologies within the skin tissue. U-Net-BN outperformed other models in segmentation accuracy, achieving the best overall performance. While both hyphae and yeast exhibited significant reductions in invasion depth and density at the highest ABL dose (180 J/cm2), only yeast was significantly inhibited at the lower dose (135 J/cm2). This novel finding emphasizes the importance of developing more effective treatment strategies for both morphologies.


We studied the effects of blue light therapy on hyphal and yeast forms of Candida albicans. Through image segmentation techniques, we discovered that the changes in invasion depth and density differed between these two forms after exposure to blue light.


Assuntos
Candida albicans, Hifas, Animais, Camundongos, Candida albicans/efeitos da radiação, Pele/microbiologia, Fototerapia/métodos, Processamento de Imagem Assistida por Computador/métodos, Luz, Antifúngicos/farmacologia, Antifúngicos/uso terapêutico, Redes Neurais de Computação, Modelos Animais de Doenças, Candidíase/microbiologia
14.
Virulence ;15(1): 2349768, 2024 12.
ArtigoemInglês |MEDLINE | ID: mdl-38736039

RESUMO

ST11 is the most common lineage among carbapenem-resistant Klebsiella pneumoniae (CRKP) infections in Asia. Diverse morphotypes resulting from genetic mutations are associated with significant differences in microbial characteristics among K. pneumoniae isolates. Here, we investigated the genetic determinants and critical characteristics associated with distinct morphotypes of ST11 CRKP. An ST11-KL47 CRKP isolate carrying a pLVPK-like virulence plasmid was isolated from a patient with a bloodstream infection; the isolate had the "mcsw" morphotype. Two distinct morphotypes ("ntrd" and "msdw") were derived from this strain during in vitro passage. Whole genome sequencing was used to identify mutations that cause the distinct morphotypes of ST11 CRKP. Transmission electron microscopy, antimicrobial susceptibility tests, growth assays, biofilm formation, virulence assays, membrane permeability assays, and RNA-seq analysis were used to investigate the specific characteristics associated with different morphotypes of ST11 CRKP. Compared with the parental mcsw morphotype, the ntrd morphotype resulted from mutation of genes involved in capsular polysaccharide biosynthesis (wza, wzc, and wbaP), a result validated by gene knockout experiments. This morphotype showed capsule deficiency and lower virulence potential, but higher biofilm production. By contrast, the msdw morphotype displayed competition deficiency and increased susceptibility to chlorhexidine and polymyxin B. Further analyses indicated that these characteristics were caused by interruption of the sigma factor gene rpoN by insertion mutations and deletion of the rpoN gene, which attenuated membrane integrity presumably by downregulating the phage shock protein operon. These data expand current understanding of genetic, virulence, and antimicrobial resistance characteristics associated with distinct morphotypes in ST11 CRKP.


Assuntos
Antibacterianos, Biofilmes, Carbapenêmicos, Infecções por Klebsiella, Klebsiella pneumoniae, Testes de Sensibilidade Microbiana, Klebsiella pneumoniae/genética, Klebsiella pneumoniae/efeitos dos fármacos, Klebsiella pneumoniae/patogenicidade, Virulência, Infecções por Klebsiella/microbiologia, Humanos, Antibacterianos/farmacologia, Biofilmes/crescimento & desenvolvimento, Carbapenêmicos/farmacologia, Animais, Enterobacteriáceas Resistentes a Carbapenêmicos/genética, Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos, Camundongos, Mutação, Sequenciamento Completo do Genoma, Plasmídeos/genética, Farmacorresistência Bacteriana
15.
Int Immunopharmacol ;135: 112317, 2024 May 25.
ArtigoemInglês |MEDLINE | ID: mdl-38796965

RESUMO

Colorectal cancer (CRC) is a significant global health challenge, with increasing rates of incidence and mortality. Despite advancements in immunotherapy, resistance, particularly due to T cell exhaustion, remains a major hurdle. This study explores the role of YWHAH, mediated by N4-acetylcytidine (ac4C) modification, in CRC progression and its impact on CD8+ T cell exhaustion. Analysis of five paired CRC patient tissue samples using acetylated RNA immunoprecipitation and sequencing (acRIP-seq)identified ac4C-modified mRNAs. Functional assays, including cell culture, transfection, qRT-PCR, and immune assays, investigated the influence of YWHAH expression on CRC advancement. Bioinformatics analysis of TCGA data assessed the correlation between YWHAH and immune responses, as well as checkpoint inhibitors. Flow cytometry and Immunohistochemistry validated these findings, complemented by a co-culture experiment involving CD8+ T cells and CRC cell lines (LOVO and HCT116). acRIP-seq revealed YWHAH as a potential driver of CRC progression, exhibiting ac4C modification-mediated stability and upregulation. High YWHAH levels correlated with adverse outcomes and immune evasion in CRC patients, showing strong associations with immune checkpoint proteins and modest correlations with CD8+ T cell infiltration. Co-culture experiments demonstrated YWHAH-induced CD8+ T cell exhaustion, characterized by decreased proliferation and increased exhaustion markers. NAT10-mediated ac4C modification enhanced YWHAH stability in CRC. The involvement of YWHAH in CD8 + T cell exhaustion suggests its potential as a therapeutic target and prognostic marker in CRC immunotherapy, highlighting the intricate interplay between epitranscriptomic modifications, the tumor microenvironment, and immune responses in CRC progression.

16.
Toxicology ;: 153838, 2024 May 24.
ArtigoemInglês |MEDLINE | ID: mdl-38797228

RESUMO

Aristolochic acid (AA)-IIIa is an AA analog present in Aristolochiaceae plants. To evaluate the chronic toxicity of AA-IIIa, mice were intragastrically administered with media control, 1mg/kg AA-IIIa, and 10mg/kg AA-IIIa, and designated as the control (CTL), AA-IIIa low dose (AA-Ⅲa-L), and AA-IIIa high dose (AA-Ⅲa-H) groups, respectively. AA-IIIa was administered three times a week, every other day, for 24 weeks (24-week time point). Thereafter, some mice were sacrificed immediately, while others were sacrificed 29 or 50 weeks after AA-Ⅲa withdrawal (53- or 74-week time point). Serum and organs were collected for biochemical and pathological analyses, respectively. Whole-genome sequencing was performed on the kidney, liver, and stomach tissues of AA-IIIa-treated mice for single-nucleotide polymorphism (SNP) detection. AA-IIIa-H mice died at 66 weeks, and the remaining mice showed moribund conditions at the 69 weeks. AA-IIIa induced minor kidney tubule injury, fibroblast hyperplasia, and forestomach carcinoma in mice. Bladder, intestine, liver, heart, spleen, lung, and testis tissues were not pathologically altered by AA-IIIa. In addition, AA-IIIa increased the C:G > A:T mutation in the kidney; however, no SNP mutation changes were observed in the liver and forestomach tissues of AA-IIIa-H mice at the 24-week time point compared with control mice. Therefore, we suspect that AA-IIIa is potentially mutagenic for mice after overdose and long-term administration. On the other hand, the forestomach is a unique organ in mice, but it does not exist in humans; thus, we hypothesize that the stomach toxicity induced by AA-Ⅲa is not a suitable reference for toxicological evaluation in humans. We recommend that Aristolochiaceae plants containing AA-IIIa should be properly supervised, and overdosing and long-term administration of drugs containing AA-IIIa should be avoided.

17.
Orthop Surg ;2024 May 21.
ArtigoemInglês |MEDLINE | ID: mdl-38773680

RESUMO

OBJECTIVE: For precise and minimally invasive treatment of ossification of the posterior longitudinal ligament of the cervical spine, the lifting segment is minimized, anterior controllable antedisplacement and fusion (ACAF) was refined and improved. In addition, the development of appropriate surgical procedures for the ossification of each segment was rarely reported. Therefore, this study aimed to compare the efficacy and safety of hybrid anterior controlled antedisplacement fusion (Hybrid ACAF) with laminoplasty for multilevel ossification of the posterior longitudinal ligament (OPLL). METHODS: Between May 2018 and May 2021, 70 patients with multilevel OPLL were divided into a hybrid ACAF group and a laminoplasty group according to surgical methods. All patients were followed up for at least 1 year. Japanese Orthopaedic Association (JOA) score and recovery rate (JOARR), (VAS, NDI) score and C2-C7 Cobb angle, the sagittal vertical axis of the neck (SVA), and complications (cerebrospinal fluid leakage, C5 paralysis, etc.) were compared between the two groups by t test or non-parametric test. RESULTS: The operation time of hybrid ACAF was longer. C5 paralysis and axial pain were more common in the laminoplasty group, while dysphagia and hoarseness were more common in the hybrid ACAF group. At the last follow-up, the hybrid ACAF group had better recovery and maintenance of cervical lordosis and sagittal plane balance and a higher JOA score and recovery rate than the laminoplasty group. CONCLUSIONS: Hybrid ACAF can reduce the number of vertebral bodies and expand the decompression range, which is safe, effective, and tailored to local conditions. Compared with laminoplasty, hybrid ACAF is a precise alternative for patients with OPLL.

18.
ACS Chem Neurosci ;2024 May 22.
ArtigoemInglês |MEDLINE | ID: mdl-38775291

RESUMO

Mapping brain activities is necessary for understanding brain physiology and discovering new treatments for neurological disorders. Such efforts have greatly benefited from the advancement in technologies for analyzing neural activity with improving temporal or spatial resolution. Here, we constructed a multielectrode array based brain activity mapping (BAM) system capable of stabilizing and orienting zebrafish larvae for recording electroencephalogram (EEG) like local field potential (LFP) signals and brain-wide calcium dynamics in awake zebrafish. Particularly, we designed a zebrafish trap chip that integrates with an eight-by-eight surface electrode array, so that brain electrophysiology can be noninvasively recorded in an agarose-free and anesthetic-free format with a high temporal resolution of 40 µs, matching the capability typically achieved by invasive LFP recording. Benefiting from the specially designed hybrid system, we can also conduct calcium imaging directly on immobilized awake larval zebrafish, which further supplies us with high spatial resolution brain-wide activity data. All of these innovations reconcile the limitations of sole LFP recording or calcium imaging, emphasizing a synergy of combining electrical and optical modalities within one unified device for activity mapping across a whole vertebrate brain with both improved spatial and temporal resolutions. The compatibility with in vivo drug treatment further makes it suitable for pharmacology studies based on multimodal measurement of brain-wide physiology.

19.
Chaos ;34(5)2024 May 01.
ArtigoemInglês |MEDLINE | ID: mdl-38775682

RESUMO

This paper investigates the formation, annihilation, and evolution mechanisms of potential energy wells in nonlinear energy sink systems. The nonlinear energy sink system is composed of multiple inner and outer magnets. Two multi-magnet energy sink (MES) architectures are designed: a single-magnet vibrator and a double-magnet vibrator. Multi-stable (bi-, tri-, quad-, penta-, hexa-, and hepta-stable) mechanisms are elaborated by the Poincaré section and bifurcation diagram concerning the magnet length, the link length, and the MES configuration. The results show that the change in the internal structural parameters of the MES system will generate different types of bifurcations (i.e., saddle-node, subcritical, and super pitchfork bifurcations) and phase trajectories and have rich nonlinear response behaviors in the low frequency and wide frequency range, which can be used for damping and vibration reduction of engineering structures, vibration control, and energy source of the microgrid.

20.
iScience ;27(5): 109713, 2024 May 17.
ArtigoemInglês |MEDLINE | ID: mdl-38746668

RESUMO

This study systematically reviewed the application of large language models (LLMs) in medicine, analyzing 550 selected studies from a vast literature search. LLMs like ChatGPT transformed healthcare by enhancing diagnostics, medical writing, education, and project management. They assisted in drafting medical documents, creating training simulations, and streamlining research processes. Despite their growing utility in assisted diagnosis and improving doctor-patient communication, challenges persisted, including limitations in contextual understanding and the risk of over-reliance. The surge in LLM-related research indicated a focus on medical writing, diagnostics, and patient communication, but highlighted the need for careful integration, considering validation, ethical concerns, and the balance with traditional medical practice. Future research directions suggested a focus on multimodal LLMs, deeper algorithmic understanding, and ensuring responsible, effective use in healthcare.

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