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1.
Sci Rep ; 14(1): 10820, 2024 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734825

RESUMO

Advancements in clinical treatment are increasingly constrained by the limitations of supervised learning techniques, which depend heavily on large volumes of annotated data. The annotation process is not only costly but also demands substantial time from clinical specialists. Addressing this issue, we introduce the S4MI (Self-Supervision and Semi-Supervision for Medical Imaging) pipeline, a novel approach that leverages advancements in self-supervised and semi-supervised learning. These techniques engage in auxiliary tasks that do not require labeling, thus simplifying the scaling of machine supervision compared to fully-supervised methods. Our study benchmarks these techniques on three distinct medical imaging datasets to evaluate their effectiveness in classification and segmentation tasks. Notably, we observed that self-supervised learning significantly surpassed the performance of supervised methods in the classification of all evaluated datasets. Remarkably, the semi-supervised approach demonstrated superior outcomes in segmentation, outperforming fully-supervised methods while using 50% fewer labels across all datasets. In line with our commitment to contributing to the scientific community, we have made the S4MI code openly accessible, allowing for broader application and further development of these methods. The code can be accessed at https://github.com/pranavsinghps1/S4MI .


Assuntos
Processamento de Imagem Assistida por Computador , Aprendizado de Máquina Supervisionado , Humanos , Processamento de Imagem Assistida por Computador/métodos , Diagnóstico por Imagem/métodos , Algoritmos
2.
Environ Res ; 252(Pt 3): 119067, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38704002

RESUMO

Environmentally persistent free radicals (EPFRs) can pose exposure risks by inducing the generation of reactive oxygen species. As a new class of pollutants, EPFRs have been frequently detected in atmospheric particulate matters. In this study, the seasonal variations and sources of EPFRs in a severe cold region in Northeastern China were comprehensively investigated, especially for the high pollution events. The geomean concentration of EPFRs in the total suspended particle was 6.58 × 1013 spins/m3 and the mean level in winter was one order of magnitude higher than summer and autumn. The correlation network analysis showed that EPFRs had significantly positive correlation with carbon component, K+ and PAHs, indicating that EPFRs were primarily emitted from combustion and pyrolysis process. The source appointment by the Positive Matrix Factorization (PMF) model indicated that the dominant sources in the heating season were coal combustion (48.4%), vehicle emission (23.1%) and biomass burning (19.4%), while the top three sources in the non-heating season were others (41.4%), coal combustion (23.7%) and vehicle emissions (21.2%). It was found that the high EPFRs in cold season can be ascribed to the extensive use of fossil fuel for heating demand; while the high EPFRs occurred in early spring were caused by the large-scale opening combustion of biomass. In summary, this study provided important basic information for better understanding the pollution characteristics of EPFRs, which suggested that the implementation of energy transformation and straw utilization was benefit for the control of EPFRs in severe cold region.

3.
J Agric Food Chem ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775141

RESUMO

A series of novel isoindoline-1-one derivatives containing piperidine moiety were designed and synthesized using natural compounds as raw materials, and their biological activities were tested for three bacterial and three fungal pathogens. These derivatives exhibited good against phytopathogenic bacteria activities against Pseudomonas syringae pv actinidiae (Psa) and Xanthomonas axonopodis pv.citri (Xac). Some compounds exhibited excellent antibacterial activities against Xanthomonas oryzae pv oryzae (Xoo). The dose of Y8 against Xoo (the maximum half lethal effective concentration (EC50) = 21.3 µg/mL) was better than that of the thiediazole copper dose (EC50 = 53.3 µg/mL). Excitingly, further studies have shown that the molecular docking of Y8 with 2FBW indicates that it can fully locate the interior of the binding pocket through hydrogen bonding and hydrophobic interactions, thereby enhancing its anti-Xoo activity. Scanning electron microscopy (SEM) studies revealed that Y8 induced the Xoo cell membrane collapse. Moreover, the proteomic results also indicate that Y8 may be a multifunctional candidate as it affects the formation of bacterial Xoo biofilms, thereby exerting antibacterial effects.

4.
Am J Gastroenterol ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38775310

RESUMO

INTRODUCTION: Concerns regarding bleeding remain in cold snare polypectomy (CSP) for small pedunculated (0-Ip) polyps. The aim of this study was to compare the risk of CSP and hot snare polypectomy (HSP) for such lesions. METHODS: Data on 0-Ip colorectal polyps ≤10 mm were extracted from a large, pragmatic, randomized trial. Immediate postpolypectomy bleeding (IPPB), defined as the perioperative use of a clip for bleeding, was evaluated through polyp-level analysis. Delayed postpolypectomy bleeding (DPPB), defined as bleeding occurring within 2 weeks postoperatively, was assessed at the patient-level among patients whose polyps were all ≤10 mm, including at least one 0-Ip polyp. RESULTS: A total of 647 0-Ip polyps (CSP: 306; HSP: 341) were included for IPPB analysis and 386 patients (CSP: 192; HSP: 194) for DPPB analysis. CSP was associated with a higher incidence of IPPB (10.8% vs 3.2%, P < 0.001) but no adverse clinical events. The procedure time of all polypectomies was shorter for CSP than for HSP (123.0 ± 117.8 vs 166.0 ± 237.7 seconds, P = 0.003), while the procedure time of polypectomies with IPPB were similar (249.8 ± 140.2 vs 227.4 ± 125.9 seconds, P = 0.64). DPPB was observed in 3 patients (1.5%) in the HSP group, including one patient (0.5%) with severe bleeding, but not in the CSP group. DISCUSSION: Despite CSP being associated with more IPPB events, it could be timely treated without adverse outcomes. Notably, no delayed bleeding occurred in the CSP group. Our findings support the use of CSP for 0-Ip polyps ≤ 10 mm.

6.
J Chin Med Assoc ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771073

RESUMO

BACKGROUND: We evaluated the diagnostic ability of macula retinal nerve fiber layer (mRNFL) thickness in preperimetric glaucoma (PPG) patients. METHODS: This prospective study included 83 patients with PPG and 83 age- and refractive error-matched normal control subjects. PPG was defined as a localized RNFL defect corresponding to glaucomatous optic disc changes with a normal visual field test. We used spectral-domain (SD) OCT to measure the circumpapillary RNFL (cpRNFL) thickness and macular ganglion cell-inner plexiform layer (GCIPL) thickness. Swept-source (SS) OCT was used to measure cpRNFL thickness, macular ganglion cell layer + inner plexiform layer (IPL) thickness (GCL+), and macular ganglion cell layer + IPL+ mRNFL thickness (GCL++). The mRNFL thickness was defined as GCL++ minus GCL+. To evaluate the diagnostic power of each parameter, the area under the receiver operating characteristics curve (AUROC) was analyzed to differentiate PPG from the normal groups. RESULTS: Using SD-OCT, all GCIPL parameters and most cpRNFL parameters, except at the nasal and temporal quadrant, were significantly lower in PPG versus normal controls. PPG eyes had significantly smaller values than normal controls for all cpRNFL and GCL parameters measured by SS-OCT, except mRNFL at the superonasal area. The inferotemporal GCL++ had the largest AUROC value (0.904), followed by inferotemporal GCL+ (0.882), inferotemporal GCIPL thickness (0.871), inferior GCL++ (0.866), inferior cpRNFL thickness by SS-OCT (0.846), inferior cpRNFL thickness by SD-OCT (0.841), and inferotemporal mRNFL thickness (0.840). The diagnostic performance was comparable between inferotemporal mRNFL thickness and the best measures of GCL (inferotemporal GCL++, p = 0.098) and cpRNFL (inferior cpRNFL thickness by SS-OCT, p = 0.546). CONCLUSION: The diagnostic ability of mRNFL thickness was comparable to that of the best measures of cpRNFL and GCL analysis for eyes with PPG. Therefore, mRNFL thickness could be a new parameter to detect early structural changes in PPG.

7.
Infect Dis Ther ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771550

RESUMO

INTRODUCTION: Ropeginterferon alfa-2b is a novel mono-pegylated proline-interferon. This clinical study aimed to evaluate its antiviral efficacy of ropeginterferon alfa-2b against SARS-CoV-2 infection. METHODS: This is a multicenter, randomized, open-label study. Adult patients with confirmed SARS-CoV-2 infection with initial cycle threshold (Ct) value < 30 and symptom onset within 4 days were enrolled. Eligible patients were randomized in a 2:1 ratio to receive a single 250-µg dose of ropeginterferon alfa-2b subcutaneously plus standard of care (SOC) or to receive SOC alone. The primary endpoint was the proportion of patients with a negative RT-PCR result for SARS-CoV-2 or discharged from the hospital before Day 8. Change in clinical status based on the World Health Organization (WHO) clinical progression scale and pulmonary infiltrations through chest radiograph were also evaluated. RESULTS: A total of 132 patients were enrolled and treated with study medication. Higher percentages of patients who achieved Ct ≥ 30 or were discharged from the hospital were observed on Day 8 and every other time point of assessment, i.e., Days 5, 11, 15, and 22, in the ropeginterferon alfa-2b group compared to the SOC alone group. However, the difference was statistically significant on Day 11 but not on Day 8. The primary endpoint was not met. The ropeginterferon alfa-2b group showed a higher improvement rate in lung infiltration on Day 5 (27.6% vs. 0.0%, p = 0.0087) and a higher improvement rate in WHO clinical progression scores on Day 8 (69.4% vs. 35.3%, p = 0.03) than those in the SOC group. No ropeginterferon alfa-2b-related serious adverse event was observed. CONCLUSION: Our data show that ropeginterferon alfa-2b with SOC shortened the duration of SARS-CoV-2 shedding compared with SOC alone. In addition, ropeginterferon alfa-2b as an additional therapy could be beneficial by improving lung infiltration.

8.
Plast Reconstr Surg Glob Open ; 12(5): e5812, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38752217

RESUMO

Background: Antithrombotic agents are used after free-flap surgery to prevent thrombus formation and improve flap outcomes. However, the reports vary. Therefore, this meta-analysis aimed to elucidate the need for antithrombotic agents in this context. Methods: We searched for studies that compared the outcomes of patients undergoing free-flap surgery with or without postoperative antithrombotic agents in the PubMed, Cochrane, and ClinicalTrials.gov databases. The primary outcome was total flap failure, with secondary outcomes including partial flap failure, pedicle thrombosis, and bleeding/hematoma. The relative risks (RRs) of outcomes with or without antithrombotic use were evaluated. Results: Fifteen studies (n = 6755 cases) were included. Antithrombotic agents did not reduce flap failure or pedicle thrombosis risks but increased bleeding and hematoma risks (RR, 1.535). Subgroup analyses by antiplatelet and anticoagulant use demonstrated results similar to those of antithrombotic use. The RR of bleeding/hematoma was 1.761 and 2.740 in the antiplatelet and anticoagulant groups, respectively. Postoperative dextran-40 administration reduced the risk of partial flap failure, with an RR of 0.535. Conclusions: Postoperative antithrombotic, antiplatelet, or anticoagulant use did not change the risk of total/partial flap failure or pedicle thrombosis but increased the risk of hematoma/bleeding. Postoperative use of dextran-40 reduced the risk of partial flap failure. Increased intraflap blood flow may decrease the risk of partial flap failure. However, dextran-40 may cause severe pulmonary distress. Further prospective studies are required to evaluate the effects of these agents on thrombus formation, intraflap blood flow, and partial flap failure risk.

9.
Biochem Biophys Res Commun ; 717: 150045, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38718572

RESUMO

The ubiquitin-proteasome system (UPS) plays a key role in maintaining cellular protein homeostasis and participates in modulating various cellular functions. Target of rapamycin (TOR), a highly conserved Ser/Thr kinase found across species from yeasts to humans, forms two multi-protein complexes, TORC1 and TORC2, to orchestrate cellular processes crucial for optimal growth, survival, and stress responses. While UPS-mediated regulation of mammalian TOR complexes has been documented, the ubiquitination of yeast TOR complexes remains largely unexplored. Here we report a functional interplay between the UPS and TORC2 in Saccharomyces cerevisiae. Using avo3-2ts, a temperature-sensitive mutant of the essential TORC2 component Avo3 exhibiting TORC2 defects at restrictive temperatures, we obtained evidence for UPS-dependent protein degradation and downregulation of the TORC2 component Avo2. Our results established the involvement of the E3 ubiquitin ligase Ubr1 and its catalytic activity in mediating Avo2 degradation in cells with defective Avo3. Coimmunoprecipitation revealed the interaction between Avo2 and Ubr1, indicating Avo2 as a potential substrate of Ubr1. Furthermore, depleting Ubr1 rescued the growth of avo3-2ts cells at restrictive temperatures, suggesting an essential role of Avo2 in sustaining cell viability under heat stress and/or TORC2 dysfunction. This study uncovers a role of UPS in yeast TORC2 regulation, highlighting the impact of protein degradation control on cellular signaling.


Assuntos
Regulação para Baixo , Alvo Mecanístico do Complexo 2 de Rapamicina , Complexo de Endopeptidases do Proteassoma , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Ubiquitina-Proteína Ligases , Ubiquitina , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Proteólise , Ubiquitinação
10.
Phys Med Biol ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38718814

RESUMO

OBJECTIVE: To evaluate the feasibility of using a deep learning dose prediction approach to identify patients who could benefit most from proton therapy based on the normal tissue complication probability (NTCP) model. Approach: Two 3D UNets were established to predict photon and proton doses. A dataset of 95 patients with localized prostate cancer was randomly partitioned into 55, 10, and 30 for training, validation, and testing, respectively. We selected NTCP models for late rectum bleeding and acute urinary urgency of grade 2 or higher to quantify the benefit of proton therapy. Propagated uncertainties of predicted ΔNTCPs resulting from the dose prediction errors were calculated. Patient selection accuracies for a single endpoint and a composite evaluation were assessed under different ΔNTCP thresholds. Main results: Our deep learning-based dose prediction technique can reduce the time spent on plan comparison from approximately 2 days to as little as 5 seconds. The expanded uncertainty of predicted ΔNTCPs for rectum and bladder endpoints propagated from the dose prediction error were 0.0042 and 0.0016, respectively, which is less than one-third of the acceptable tolerance. The averaged selection accuracies for rectum bleeding, urinary urgency, and composite evaluation were 90%, 93.5%, and 93.5%, respectively. Significance: Our study demonstrates that deep learning dose prediction and NTCP evaluation scheme could distinguish the NTCP differences between photon and proton treatment modalities. In addition, the dose prediction uncertainty does not significantly influence the decision accuracy of NTCP-based patient selection for proton therapy. Therefore, automated deep learning dose prediction and NTCP evaluation schemes can potentially be used to screen large patient populations and to avoid unnecessary delays in the start of prostate cancer radiotherapy in the future.

11.
J Formos Med Assoc ; 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38710607

RESUMO

BACKGROUND/PURPOSE: Taiwan is one of the countries with the lowest birth rate in the world. We investigated factors associated with the time to diagnosis and treatment of infertility in Taiwan. METHODS: The study was conducted through an online questionnaire in December 2021. The questionnaire was adapted from a previously published multinational survey, and culture-specific questions were added. 91 infertile patients and 89 partners of patients in Taiwan, aged 20- to 45- year-old, were included. RESULTS: The average duration before diagnosis was 2.9 years, followed by 1.5 years before treatment. Older age at marriage (p = 0.0024), higher education level (P = 0.0001), and a higher gender equality score (p = 0.0031) were associated with earlier diagnosis. Conversely, folk therapy use was linked to later diagnosis (p < 0.0001) and treatment (p < 0.0001). Notably, in the female (p = 0.039) and patient (p = 0.0377) subgroups, a higher gender equality score was associated with a shorter duration of folk therapy. Subjectively, the most frequent factor influencing treatment decision was affordability or lack thereof. The government subsidy for in vitro fertilization led to increased treatment willingness for 46.3% of respondents, and 47.3% reported more likely to pursue earlier treatment. CONCLUSIONS: This study highlights the influence of education, gender equality, folk therapy, and government subsidy on fertility care decisions. To improve the timeliness of infertility healthcare in Taiwan, potential strategies include promoting education, fostering gender equality, providing financial support, and raising awareness on the association between folk therapy and delayed medical care.

12.
Nat Commun ; 15(1): 3729, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702330

RESUMO

The unique virus-cell interaction in Epstein-Barr virus (EBV)-associated malignancies implies targeting the viral latent-lytic switch is a promising therapeutic strategy. However, the lack of specific and efficient therapeutic agents to induce lytic cycle in these cancers is a major challenge facing clinical implementation. We develop a synthetic transcriptional activator that specifically activates endogenous BZLF1 and efficiently induces lytic reactivation in EBV-positive cancer cells. A lipid nanoparticle encapsulating nucleoside-modified mRNA which encodes a BZLF1-specific transcriptional activator (mTZ3-LNP) is synthesized for EBV-targeted therapy. Compared with conventional chemical inducers, mTZ3-LNP more efficiently activates EBV lytic gene expression in EBV-associated epithelial cancers. Here we show the potency and safety of treatment with mTZ3-LNP to suppress tumor growth in EBV-positive cancer models. The combination of mTZ3-LNP and ganciclovir yields highly selective cytotoxic effects of mRNA-based lytic induction therapy against EBV-positive tumor cells, indicating the potential of mRNA nanomedicine in the treatment of EBV-associated epithelial cancers.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Lipossomos , Nanopartículas , Transativadores , Humanos , Herpesvirus Humano 4/genética , Transativadores/metabolismo , Transativadores/genética , Infecções por Vírus Epstein-Barr/virologia , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Animais , Nanopartículas/química , Linhagem Celular Tumoral , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ativação Viral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Camundongos Nus , Feminino
13.
Mikrochim Acta ; 191(6): 298, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709403

RESUMO

As a real-time fluid biopsy method, the detection of circulating tumor cells (CTCs) provides important information for the early diagnosis, precise treatment, and prognosis of cancer. However, the low density of CTCs in the peripheral blood hampers their capture and detection with high sensitivity and selectivity using currently available methods. Hence, we designed a sandwich-type electrochemical aptasensor that utilizes holothurian-shaped AuPd nanoparticles (AuPd HSs), tetrahedral DNA nanostructures (TDNs), and CuPdPt nanowire networks (NWs) interwoven with a graphdiyne (GDY) sheet for ultrasensitive non-destructive detection of MCF-7 breast cancer cells. CuPdPt NW-GDY effectively enhanced the electron transfer rate and coupled with the loaded TDNs. The TDNs could capture MCF-7 cells with precision and firmness, and the resulting composite complex was combined with AuPd HSs to form a sandwich-type structure. This novel aptasensor showed a linear range between 10 and 106 cells mL-1 and an ultralow detection limit of 7 cells mL-1. The specificity, stability, and repeatability of the measurements were successfully verified. Moreover, we used benzonase nuclease to achieve non-destructive recovery of cells for further clinical studies. According to the results, our aptasensor was more sensitive measuring the number of CTCs than other approaches because of the employment of TDNs, CuPdPt NW-GDY, and AuPd HSs. We designed a reliable sensor system for the detection of CTCs in the peripheral blood, which could serve as a new approach for cancer diagnosis at an early stage.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Nanopartículas Metálicas , Células Neoplásicas Circulantes , Paládio , Células Neoplásicas Circulantes/patologia , Humanos , Células MCF-7 , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Aptâmeros de Nucleotídeos/química , Ouro/química , DNA/química , Técnicas Biossensoriais/métodos , Paládio/química
14.
Arch Toxicol ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753188

RESUMO

Long interspersed nuclear element-1 (LINE-1) methylation serves as an indicator of global DNA methylation. This study explored the correlation between LINE-1 methylation and chronic kidney disease (CKD). We also evaluated whether LINE-1 methylation could modify the association between CKD and metal exposure. A total of 213 patients with clinically defined CKD, without hemodialysis and 416 age and sex matched controls were recruited. Levels of LINE-1 methylation, total urinary arsenic, blood lead, blood cadmium, and plasma selenium were assessed. The results reveal a positive association between LINE-1 methylation and CKD, with an odds ratio (OR) of 5.30 (95% confidence interval: 2.81 to 9.99). Total urinary arsenic and blood cadmium concentrations were positively related with LINE-1 methylation. This study was the first to observe that low plasma selenium, high blood cadmium, and high blood lead levels significantly and additively interact with increased LINE-1 methylation to increase the OR of CKD. Additionally, high LINE-1 methylation interacted multiplicatively with low plasma selenium to increase the OR of CKD (p < 0.001). This study highlighted the significant association between LINE-1 hypermethylation and CKD. Furthermore, the results demonstrate that LINE-1 methylation can interact with high blood cadmium or low plasma selenium to affect CKD risk.

15.
Environ Int ; 188: 108671, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38749119

RESUMO

OBJECTIVE: Parabens are a group of substances commonly employed as antimicrobial preservatives. The effect of parabens on the development of neurotoxicity in children is still controversial. This study aimed to explore the associations between parabens exposure and children's neurodevelopmental performance, emphasizing potential sex differences and the combined effects of parabens. METHODS: We used the long-term follow-up study of Taiwanese generation, Taiwan Birth Panel Study II (TBPS II). We recruited the group of children at 6-8 years old. And, we measured parabens in children urine, including methylparaben (MP), ethylparaben (EP), propylparaben (PP) and butylparaben (BP). Children's attention-related performance was evaluated using the Conners Kiddie Continuous Performance Test 2nd Edition (K-CPT 2). The study employed both linear regression and mixture analysis quantile g-computation (QGC) methods to discern associations. A stratified analysis by sex and QGC was implemented to delve deeper into the cumulative effects of parabens. RESULTS: A total of 446 subjects completed both the parabens analysis and the K-CPT 2 survey. The overall association between parabens and neurodevelopmental performance was not pronounced, but discernible sex differences emerged. In the single pollutant analysis, elevated PP concentrations were associated with higher K-CPT 2 scores particularly in detectability (d') (ß = 0.92 [95 % CI = 0.15 to 1.69]) and commissions (ß = 0.95 [95 % CI = 0.12 to 1.78]), among girls. Further, in the mixture analysis, a significant association between PP and detectability (d') was observed in girls (ß = 1.68 [95 % CI = 0.11 to 3.26]). CONCLUSIONS: This study identified sex-specific associations between parabens and attention performance. Consistent outcomes across single and mixture analysis methods. Further research is crucial to clarify these causal associations.

16.
Mol Carcinog ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607240

RESUMO

DNA methylation, an epigenetic regulatory mechanism dictating gene transcription, plays a critical role in the occurrence and development of cancer. However, the molecular underpinnings of LINC00987 methylation in the regulation of lung adenocarcinoma (LUAD) remain elusive. This study investigated LINC00987 expression in LUAD patients through analysis of The Cancer Genome Atlas data sets. Quantitative real-time polymerase chain reaction (RT-qPCR) and fluorescence in situ hybridization assays were used to assess LINC00987 expression in LUAD. The bisulfite genomic sequence PCR (BSP) assay was used to determine the methylation levels of the LINC00987 promoter. The interaction between LINC00987 and SND1 was elucidated via immunoprecipitation and RNA pull-down assays. The functional significance of LINC00987 and SND1 in Calu-3 and NCI-H1688 cells was evaluated in vitro through CCK-8, EdU, Transwell, flow cytometry, and vasculogenic mimicry (VM) tube formation assays. LINC00987 expression decreased in LUAD concomitant with hypermethylation of the promoter region, while hypomethylation of the LINC00987 promoter in LUAD tissues correlated with tumor progression. Treatment with 5-Aza-CdR augmented LINC00987 expression and inhibited tumor growth. Mechanistically, LINC00987 overexpression impeded LUAD progression and VM through direct binding with SND1, thereby facilitating its phosphorylation and subsequent degradation. Additionally, overexpression of SND1 counteracted the adverse effects of LINC00987 downregulation on cell proliferation, apoptosis, cell migration, invasion, and VM in LUAD in vitro. In conclusion, this pioneering study focuses on the expression and function of LINC00987 and reveals that hypermethylation of the LINC00987 gene may contribute to LUAD progression. LINC00987 has emerged as a potential tumor suppressor gene in tumorigenesis through its binding with SND1 to facilitate its phosphorylation and subsequent degradation.

17.
JBMR Plus ; 8(5): ziae031, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38606146

RESUMO

Nonunion resulting from early bone resorption is common after bone transplantation surgery. In these patients, instability or osteoporosis causes hyperactive catabolism relative to anabolism, leading to graft resorption instead of fusion. Systemic zoledronate administration inhibits osteoclastogenesis and is widely used to prevent osteoporosis; however, evidence on local zoledronate application is controversial due to osteoblast cytotoxicity, uncontrolled dosing regimens, and local release methods. We investigated the effects of zolendronate on osteoclastogenesis and osteogenesis and explored the corresponding signaling pathways. In vitro cytotoxicity and differentiation of MC3T3E1 cells, rat bone marrow stromal cells (BMSCs) and preosteoclasts (RAW264.7 cells) were evaluated with different zolendronate concentrations. In vivo bone regeneration ability was tested by transplanting different concentrations of zolendronate with ß-tricalcium phosphate (TCP) bone substitute into rat femoral critical-sized bone defects. In vitro, zolendronate concentrations below 2.5 × 10-7 M did not compromise viability in the three cell lines and did not promote osteogenic differentiation in MC3T3E1 cells and BMSCs. In RAW264.7 cells, zoledronate inhibited extracellular regulated protein kinases and c-Jun n-terminal kinase signaling, downregulating c-Fos and NFATc1 expression, with reduced expression of fusion-related dendritic cell­specific transmembrane protein and osteoclast-specific Ctsk and tartrate-resistant acid phosphatase (. In vivo, histological staining revealed increased osteoid formation and neovascularization and reduced fibrotic tissue with 500 µM and 2000 µM zolendronate. More osteoclasts were found in the normal saline group after 6 weeks, and sequential osteoclast formation occurred after zoledronate treatment, indicating inhibition of bone resorption during early callus formation without inhibition of late-stage bone remodeling. In vivo, soaking ß-TCP artificial bone with 500 µM or 2000 µM zoledronate is a promising approach for bone regeneration, with potential applications in bone transplantation.

18.
Biochem Biophys Res Commun ; 710: 149874, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38581950

RESUMO

Synaptic plasticity is crucial as it dynamically molds the strength and connectivity of neural circuits, influencing learning, memory, and the development of neurological disorders. Metformin, a widely prescribed anti-diabetic medication, has been shown to readily cross the blood-brain barrier (BBB) and the placenta. However, its prolonged impact on neuronal morphology and functions remains underexplored. In this study, we investigated the influence of metformin on dendrite development and synaptic plasticity in embryonic brains and primary rat cortical neurons. Our findings reveal a negative modulation of dendrite development by metformin, as evidenced by altered dendritic arborization, impaired dendritic spine morphology and disruptions in synaptic plasticity, suggesting a potential link between metformin exposure and aberrations in neuronal connectivity. In addition, we extend our insights to the impact of maternal metformin exposure on embryonic brains, revealing a significant inhibition of dendrite development in E18.5 rat brains. In conclusion, this study adds to the expanding knowledge base on the non-metabolic effects of metformin, emphasizing the significance of assessing its potential influence on both neuronal structure and function. There is an urgent need for further investigations into the enduring impact of prolonged metformin administration on the structural and functional aspects of neurons.


Assuntos
Plasticidade Neuronal , Neurônios , Gravidez , Feminino , Ratos , Animais , Plasticidade Neuronal/fisiologia , Aprendizagem , Barreira Hematoencefálica , Dendritos
19.
Elife ; 132024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602170

RESUMO

Stains are known to be anti-inflammatory, but the mechanism remains poorly understood. Here we show that macrophages, either treated with statin in vitro or from statin-treated mice, have reduced cholesterol levels and higher expression of Jmjd3, a H3K27me3 demethylase. We provide evidence that lowering cholesterol levels in macrophages suppresses the ATP synthase in the inner mitochondrial membrane (IMM) and changes the proton gradient in the mitochondria. This activates NFkB and Jmjd3 expression to remove the repressive marker H3K27me3. Accordingly, the epigenome is altered by the cholesterol reduction. When subsequently challenged by the inflammatory stimulus LPS (M1), both macrophages treated with statins in vitro or isolated from statin-treated mice in vivo, express lower levels pro-inflammatory cytokines than controls, while augmenting anti-inflammatory Il10 expression. On the other hand, when macrophages are alternatively activated by IL4 (M2), statins promote the expression of Arg1, Ym1, and Mrc1. The enhanced expression is correlated with the statin-induced removal of H3K27me3 from these genes prior to activation. In addition, Jmjd3 and its demethylase activity are necessary for cholesterol to modulate both M1 and M2 activation. We conclude that upregulation of Jmjd3 is a key event for the anti-inflammatory function of statins on macrophages.

20.
J Biomech ; 168: 112059, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631187

RESUMO

The progression of cardiovascular disease is intricately influenced by a complex interplay between physiological pathways, biochemical processes, and physical mechanisms. This study aimed to develop an in-silico physics-based approach to comprehensively model the multifaceted vascular pathophysiological adaptations. This approach focused on capturing the progression of proximal pulmonary arterial hypertension, which is significantly associated with the irreversible degradation of arterial walls and compensatory stress-induced growth and remodeling. This study incorporated critical characteristics related to the distinct time scales for the deformation, thus reflecting the impact of mean pressure on artery growth and tissue damage. The in-silico simulation of the progression of pulmonary hypertension was realized based on computational code combined with the finite element method (FEM) for the simulation of disease progression. The parametric studies further explored the consequences of these irreversible processes. This computational modeling approach may advance our understanding of pulmonary hypertension and its progression.


Assuntos
Simulação por Computador , Progressão da Doença , Hipertensão Pulmonar , Modelos Cardiovasculares , Artéria Pulmonar , Humanos , Hipertensão Pulmonar/fisiopatologia , Artéria Pulmonar/fisiopatologia , Análise de Elementos Finitos
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