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1.
Nature ; 614(7946): 81-87, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36725999

RESUMO

Micro-LEDs (µLEDs) have been explored for augmented and virtual reality display applications that require extremely high pixels per inch and luminance1,2. However, conventional manufacturing processes based on the lateral assembly of red, green and blue (RGB) µLEDs have limitations in enhancing pixel density3-6. Recent demonstrations of vertical µLED displays have attempted to address this issue by stacking freestanding RGB LED membranes and fabricating top-down7-14, but minimization of the lateral dimensions of stacked µLEDs has been difficult. Here we report full-colour, vertically stacked µLEDs that achieve, to our knowledge, the highest array density (5,100 pixels per inch) and the smallest size (4 µm) reported to date. This is enabled by a two-dimensional materials-based layer transfer technique15-18 that allows the growth of RGB LEDs of near-submicron thickness on two-dimensional material-coated substrates via remote or van der Waals epitaxy, mechanical release and stacking of LEDs, followed by top-down fabrication. The smallest-ever stack height of around 9 µm is the key enabler for record high µLED array density. We also demonstrate vertical integration of blue µLEDs with silicon membrane transistors for active matrix operation. These results establish routes to creating full-colour µLED displays for augmented and virtual reality, while also offering a generalizable platform for broader classes of three-dimensional integrated devices.

2.
Nucleic Acids Res ; 52(10): 5756-5773, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38587189

RESUMO

Dynamic interaction between BRCA2 and telomeric G-quadruplexes (G4) is crucial for maintaining telomere replication homeostasis. Cells lacking BRCA2 display telomeric damage with a subset of these cells bypassing senescence to initiate break-induced replication (BIR) for telomere synthesis. Here we show that the abnormal stabilization of telomeric G4 following BRCA2 depletion leads to telomeric repeat-containing RNA (TERRA)-R-loop accumulation, triggering liquid-liquid phase separation (LLPS) and the assembly of Alternative Lengthening of Telomeres (ALT)-associated promyelocytic leukemia (PML) bodies (APBs). Disruption of R-loops abolishes LLPS and impairs telomere synthesis. Artificial engineering of telomeric LLPS restores telomere synthesis, underscoring the critical role of LLPS in ALT. TERRA-R-loops also recruit Polycomb Repressive Complex 2 (PRC2), leading to tri-methylation of Lys27 on histone H3 (H3K27me3) at telomeres. Half of paraffin-embedded tissue sections from human breast cancers exhibit APBs and telomere length heterogeneity, suggesting that BRCA2 mutations can predispose individuals to ALT-type tumorigenesis. Overall, BRCA2 abrogation disrupts the dynamicity of telomeric G4, producing TERRA-R-loops, finally leading to the assembly of telomeric liquid condensates crucial for ALT. We propose that modulating the dynamicity of telomeric G4 and targeting TERRA-R-loops in telomeric LLPS maintenance may represent effective therapeutic strategies for treating ALT-like cancers with APBs, including those with BRCA2 disruptions.


Assuntos
Proteína BRCA2 , Replicação do DNA , Quadruplex G , Homeostase do Telômero , Telômero , Humanos , Telômero/metabolismo , Telômero/genética , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Homeostase do Telômero/genética , Replicação do DNA/genética , Histonas/metabolismo , Histonas/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Estruturas R-Loop , Complexo Repressor Polycomb 2/metabolismo , Complexo Repressor Polycomb 2/genética , Linhagem Celular Tumoral , Feminino , Separação de Fases
3.
Am J Hum Genet ; 109(10): 1814-1827, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36167069

RESUMO

Ischemic stroke, caused by vessel blockage, results in cerebral infarction, the death of brain tissue. Previously, quantitative trait locus (QTL) mapping of cerebral infarct volume and collateral vessel number identified a single, strong genetic locus regulating both phenotypes. Additional studies identified RAB GTPase-binding effector protein 2 (Rabep2) as the casual gene. However, there is yet no evidence that variation in the human ortholog of this gene plays any role in ischemic stroke outcomes. We established an in vivo evaluation platform in mice by using adeno-associated virus (AAV) gene replacement and verified that both mouse and human RABEP2 rescue the mouse Rabep2 knockout ischemic stroke volume and collateral vessel phenotypes. Importantly, this cross-species complementation enabled us to experimentally investigate the functional effects of coding sequence variation in human RABEP2. We chose four coding variants from the human population that are predicted by multiple in silico algorithms to be damaging to RABEP2 function. In vitro and in vivo analyses verify that all four led to decreased collateral vessel connections and increased infarct volume. Thus, there are naturally occurring loss-of-function alleles. This cross-species approach will expand the number of targets for therapeutics development for ischemic stroke.


Assuntos
AVC Isquêmico , Alelos , Animais , Encéfalo/metabolismo , Mapeamento Cromossômico , Humanos , Camundongos , Proteínas de Transporte Vesicular/genética , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
4.
Plant Cell ; 34(1): 351-373, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-34718777

RESUMO

Autophagy is an intracellular trafficking mechanism by which cytosolic macromolecules and organelles are sequestered into autophagosomes for degradation inside the vacuole. In various eukaryotes including yeast, metazoans, and plants, the precursor of the autophagosome, termed the phagophore, nucleates in the vicinity of the endoplasmic reticulum (ER) with the participation of phosphatidylinositol 3-phosphate (PI3P) and the coat protein complex II (COPII). Here we show that Arabidopsis thaliana FYVE2, a plant-specific PI3P-binding protein, provides a functional link between the COPII machinery and autophagy. FYVE2 interacts with the small GTPase Secretion-associated Ras-related GTPase 1 (SAR1), which is essential for the budding of COPII vesicles. FYVE2 also interacts with ATG18A, another PI3P effector on the phagophore membrane. Fluorescently tagged FYVE2 localized to autophagic membranes near the ER and was delivered to vacuoles. SAR1 fusion proteins were also targeted to the vacuole via FYVE2-dependent autophagy. Either mutations in FYVE2 or the expression of dominant-negative mutant SAR1B proteins resulted in reduced autophagic flux and the accumulation of autophagic organelles. We propose that FYVE2 regulates autophagosome biogenesis through its interaction with ATG18A and the COPII machinery, acting downstream of ATG2.


Assuntos
Arabidopsis , Autofagossomos , Proteínas de Transporte Vesicular , Arabidopsis/genética , Arabidopsis/metabolismo , Autofagossomos/metabolismo , Proteínas de Transporte Vesicular/metabolismo
5.
Nano Lett ; 24(29): 8920-8928, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38874568

RESUMO

Blood-contacting medical devices (BCDs) require antithrombotic, antibacterial, and low-friction surfaces. Incorporating a nanostructured surface with the functional hydrogel onto BCD surfaces can enhance the performances; however, their fabrication remains challenging. Here, we introduce a straightforward method to fabricate a multifunctional hydrogel-based nanostructure on BCD surfaces using O-carboxymethyl chitosan-based short nanofibers (CMC-SNFs). CMC-SNFs, fabricated via electrospinning and cutting processes, are easily sprayed and entangled onto the BCD surface. The deposited CMC-SNFs form a robust nanoweb layer via fusion at the contact area of the nanofiber interfaces. The superhydrophilic CMC-SNF nanoweb surface creates a water-bound layer that effectively prevents the nonspecific adhesion of bacteria and blood cells, thereby enhancing both antimicrobial and antithrombotic performances. Furthermore, the CMC-SNF nanoweb exhibits excellent lubricity and durability on the bovine aorta. The demonstration results of the CMC-SNF coating on catheters and sheaths provide evidence of its capability to apply multifunctional surfaces simply for diverse BCDs.


Assuntos
Quitosana , Hidrogéis , Nanofibras , Quitosana/química , Quitosana/análogos & derivados , Nanofibras/química , Animais , Hidrogéis/química , Bovinos , Propriedades de Superfície , Humanos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química
6.
Gut ; 73(3): 533-540, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-37907259

RESUMO

OBJECTIVE: We explored clinical implications of the new definition of metabolic dysfunction-associated steatotic liver disease (MASLD) by assessing its prevalence and associated cardiovascular disease (CVD) risk. DESIGN: From nationwide health screening data, we identified 9 775 066 adults aged 20-79 who underwent health examination in 2009. Participants were categorised into four mutually exclusive groups: (1) MASLD; (2) MASLD with increased alcohol intake (MetALD); (3) MASLD with other combined aetiology (the three collectively referred to as MASLD/related steatotic liver disease (SLD)); and (4) no MASLD/related SLD. SLD was determined by fatty liver index ≥30. The primary outcome was CVD event, defined as a composite of myocardial infarction, ischaemic stroke, heart failure or cardiovascular death. RESULTS: The prevalence of MASLD, MetALD and MASLD with other combined aetiology was 27.5%, 4.4% and 1.5%, respectively. A total of 8 808 494 participants without prior CVD were followed up for a median of 12.3 years, during which 272 863 CVD events occurred. The cumulative incidence and multivariable-adjusted risk of CVD were higher in participants with MASLD/related SLD than in those without (HR 1.38 (95% CI 1.37 to 1.39)). Multivariable-adjusted HR (95% CI) of CVD events was 1.39 (1.38 to 1.40) for MASLD, 1.28 (1.26 to 1.30) for MetALD and 1.30 (1.26 to 1.34) for MASLD with other combined aetiology compared to the absence of any of these conditions. CVD risk was also higher in participants with metabolic dysfunction-associated fatty liver disease or non-alcoholic fatty liver disease than in those without the respective condition. CONCLUSION: Over one-third of Korean adults have MASLD/related SLD and bear a high CVD risk.


Assuntos
Isquemia Encefálica , Doenças Cardiovasculares , Doenças Metabólicas , Hepatopatia Gordurosa não Alcoólica , Acidente Vascular Cerebral , Adulto , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Metabólicas/complicações , Doenças Metabólicas/epidemiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia
7.
J Neurosci ; 43(1): 113-124, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36332977

RESUMO

The hippocampus is crucial for retrieval of contextual memories. The activation of a subpopulation of neurons in the dorsal CA1 (dCA1) of the hippocampus is required for memory retrieval. Given that hippocampal neurons exhibit distinct patterns of response during memory retrieval, the activity patterns of individual neurons or ensembles may be critically involved in memory retrieval. However, this relation has been unclear. To investigate this question, we used an in vivo microendoscope calcium imaging technique to optically record neuronal activity in the dCA1 of male and female mice. We observed that a portion of dCA1 neurons increased their responses to the learned context after contextual fear conditioning (FC), resulting in overall increase in response of neuronal population compared with simple context exposure. Such increased response was specific to the conditioned context as it disappeared in neutral context. The magnitude of increase in neuronal responses by FC was proportional to memory strength during retrieval. The increases in activity preferentially occurred during the putative sharp wave ripple events and were not simply because of animal's movement and immobility. At the ensemble level, synchronous cell activity patterns were associated with memory retrieval. Accordingly, when such patterns were more similar between conditioned and neutral context, animals displayed proportionally more similar level of freezing. Together, these results indicate that increase in responses of individual neurons and synchronous cell activity patterns in the dCA1 neuronal network are critically involved in representing a contextual memory recall.SIGNIFICANCE STATEMENT Neurons in the dorsal CA1 of the hippocampus are crucial for memory retrieval. By using in vivo calcium imaging methods for recording neuronal activity, we demonstrate that dCA1 neurons increased their responses to the learned context specifically by FC and such changes correlated with memory strength during retrieval. Moreover, distinct synchronous cell activity patterns were formed by FC and involved in representing contextual memory retrieval. These findings reveal dynamic activity features of dCA1 neurons that are involved in contextual memory retrieval.


Assuntos
Cálcio , Memória , Camundongos , Masculino , Feminino , Animais , Memória/fisiologia , Hipocampo/fisiologia , Neurônios/fisiologia
8.
Circulation ; 147(2): 142-153, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36382596

RESUMO

BACKGROUND: Identifying genetic variants that affect the level of cell cycle reentry and establishing the degree of cell cycle progression in those variants could help guide development of therapeutic interventions aimed at effecting cardiac regeneration. We observed that C57Bl6/NCR (B6N) mice have a marked increase in cardiomyocyte S-phase activity after permanent coronary artery ligation compared with infarcted DBA/2J (D2J) mice. METHODS: Cardiomyocyte cell cycle activity after infarction was monitored in D2J, (D2J×B6N)-F1, and (D2J×B6N)-F1×D2J backcross mice by means of bromodeoxyuridine or 5-ethynyl-2'-deoxyuridine incorporation using a nuclear-localized transgenic reporter to identify cardiomyocyte nuclei. Genome-wide quantitative trait locus analysis, fine scale genetic mapping, whole exome sequencing, and RNA sequencing analyses of the backcross mice were performed to identify the gene responsible for the elevated cardiomyocyte S-phase phenotype. RESULTS: (D2J×B6N)-F1 mice exhibited a 14-fold increase in cardiomyocyte S-phase activity in ventricular regions remote from infarct scar compared with D2J mice (0.798±0.09% versus 0.056±0.004%; P<0.001). Quantitative trait locus analysis of (D2J×B6N)-F1×D2J backcross mice revealed that the gene responsible for differential S-phase activity was located on the distal arm of chromosome 3 (logarithm of the odds score=6.38; P<0.001). Additional genetic and molecular analyses identified 3 potential candidates. Of these, Tnni3k (troponin I-interacting kinase) is expressed in B6N hearts but not in D2J hearts. Transgenic expression of TNNI3K in a D2J genetic background results in elevated cardiomyocyte S-phase activity after injury. Cardiomyocyte S-phase activity in both Tnni3k-expressing and Tnni3k-nonexpressing mice results in the formation of polyploid nuclei. CONCLUSIONS: These data indicate that Tnni3k expression increases the level of cardiomyocyte S-phase activity after injury.


Assuntos
Miócitos Cardíacos , Troponina I , Camundongos , Animais , Troponina I/metabolismo , Camundongos Endogâmicos DBA , Miócitos Cardíacos/metabolismo , Ciclo Celular , Proliferação de Células , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo
9.
Breast Cancer Res ; 26(1): 14, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254240

RESUMO

BACKGROUND: This study aimed to investigate the contralateral breast cancer (CBC) recurrence rate in Korean breast cancer patients according to their BRCA1/2 germline mutation status, focusing particularly on the CBC recurrence risk in BRCA1/2 negative (BRCAx) patients. METHODS: We conducted a retrospective study on 13,107 primary breast cancer patients. The patients were divided into high-risk and low-risk groups for hereditary breast cancer based on the Korean National Health Insurance Service's eligibility criteria for BRCA1/2 germline mutation testing. The high-risk group was further categorized into the BRCA mutation group, the BRCAx group, and the not tested group. We evaluated the overall survival and cumulative risk of developing CBC in these patients. RESULTS: Among 4494 high-risk patients, 973 (21.7%) underwent genetic testing for BRCA1/2 germline mutation, revealing mutations in 158 patients (16.2%). We observed significant overall survival differences across all four groups, with the high-risk, not-tested group demonstrating notably worse overall survival (p < 0.001). However, when adjusted for other prognostic factors, there was no significant differences in hazard ratio of death between the four groups. The cumulative risk of CBC also varied among the groups. Patients with BRCA1/2 mutations showed a 7.3-fold increased risk of CBC compared to the low-risk group (95% CI 4.11-13.0, p < 0.001). Interestingly, BRCAx patients also demonstrated a significantly higher risk of CBC (HR 2.77, 95% CI 1.76-4.35, p < 0.001). The prognostic importance of the BRCAx for CBC recurrence persisted after adjusting for the age and subtype, but became insignificant when the family history of breast cancer was adjusted. CONCLUSION: Breast cancer patients who are at high risk of hereditary breast cancer but with wild-type BRCA 1/2 genes (BRCAx) have increased risk of developing contralateral breast cancer when compared to the low-risk patients. More careful surveillance and follow-up can be offered to these patients especially when they have family history of breast cancer.


Assuntos
Proteína BRCA1 , Neoplasias da Mama , Humanos , Feminino , Proteína BRCA1/genética , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Estudos Retrospectivos , Proteína BRCA2/genética , República da Coreia/epidemiologia
10.
J Hepatol ; 80(1): 20-30, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37734683

RESUMO

BACKGROUND & AIMS: Recent studies reported that moderate HBV DNA levels are significantly associated with hepatocellular carcinoma (HCC) risk in hepatitis B e antigen (HBeAg)-positive, non-cirrhotic patients with chronic hepatitis B (CHB). We aimed to develop and validate a new risk score to predict HCC development using baseline moderate HBV DNA levels in patients entering into HBeAg-positive CHB from chronic infection. METHODS: This multicenter cohort study recruited 3,585 HBeAg-positive, non-cirrhotic patients who started antiviral treatment with entecavir or tenofovir disoproxil fumarate at phase change into CHB from chronic infection in 23 tertiary university-affiliated hospitals of South Korea (2012-2020). A new HCC risk score (PAGED-B) was developed (training cohort, n = 2,367) based on multivariable Cox models. Internal validation using bootstrap sampling and external validation (validation cohort, n = 1,218) were performed. RESULTS: Sixty (1.7%) patients developed HCC (median follow-up, 5.4 years). In the training cohort, age, gender, platelets, diabetes and moderate HBV DNA levels (5.00-7.99 log10 IU/ml) were independently associated with HCC development; the PAGED-B score (based on these five predictors) showed a time-dependent AUROC of 0.81 for the prediction of HCC development at 5 years. In the validation cohort, the AUROC of PAGED-B was 0.85, significantly higher than for other risk scores (PAGE-B, mPAGE-B, CAMD, and REAL-B). When stratified by the PAGED-B score, the HCC risk was significantly higher in high-risk patients than in low-risk patients (sub-distribution hazard ratio = 8.43 in the training and 11.59 in the validation cohorts, all p <0.001). CONCLUSIONS: The newly established PAGED-B score may enable risk stratification for HCC at the time of transition into HBeAg-positive CHB. IMPACT AND IMPLICATIONS: In this study, we developed and validated a new risk score to predict hepatocellular carcinoma (HCC) development in patients entering into hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) from chronic infection. The newly established PAGED-B score, which included baseline moderate HBV DNA levels (5-8 log10 IU/ml), improved on the predictive performance of prior risk scores. Based on a patient's age, gender, diabetic status, platelet count, and moderate DNA levels (5-8 log10 IU/ml) at the phase change into CHB from chronic infection, the PAGED-B score represents a reliable and easily available risk score to predict HCC development during the first 5 years of antiviral treatment in HBeAg-positive patients entering into CHB. With a scoring range from 0 to 12 points, the PAGED-B score significantly differentiated the 5-year HCC risk: low <7 points and high ≥7 points.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Humanos , Pré-Escolar , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/induzido quimicamente , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Antígenos E da Hepatite B , DNA Viral , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/induzido quimicamente , Estudos de Coortes , Infecção Persistente , Antivirais/uso terapêutico , Fatores de Risco , Vírus da Hepatite B/genética
11.
Lancet ; 402(10415): 1835-1847, 2023 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-37871608

RESUMO

BACKGROUND: No adjuvant treatment has been established for patients who remain at high risk for hepatocellular carcinoma recurrence after curative-intent resection or ablation. We aimed to assess the efficacy of adjuvant atezolizumab plus bevacizumab versus active surveillance in patients with high-risk hepatocellular carcinoma. METHODS: In the global, open-label, phase 3 IMbrave050 study, adult patients with high-risk surgically resected or ablated hepatocellular carcinoma were recruited from 134 hospitals and medical centres in 26 countries in four WHO regions (European region, region of the Americas, South-East Asia region, and Western Pacific region). Patients were randomly assigned in a 1:1 ratio via an interactive voice-web response system using permuted blocks, using a block size of 4, to receive intravenous 1200 mg atezolizumab plus 15 mg/kg bevacizumab every 3 weeks for 17 cycles (12 months) or to active surveillance. The primary endpoint was recurrence-free survival by independent review facility assessment in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT04102098. FINDINGS: The intention-to-treat population included 668 patients randomly assigned between Dec 31, 2019, and Nov 25, 2021, to either atezolizumab plus bevacizumab (n=334) or to active surveillance (n=334). At the prespecified interim analysis (Oct 21, 2022), median duration of follow-up was 17·4 months (IQR 13·9-22·1). Adjuvant atezolizumab plus bevacizumab was associated with significantly improved recurrence-free survival (median, not evaluable [NE]; [95% CI 22·1-NE]) compared with active surveillance (median, NE [21·4-NE]; hazard ratio, 0·72 [adjusted 95% CI 0·53-0·98]; p=0·012). Grade 3 or 4 adverse events occurred in 136 (41%) of 332 patients who received atezolizumab plus bevacizumab and 44 (13%) of 330 patients in the active surveillance group. Grade 5 adverse events occurred in six patients (2%, two of which were treatment related) in the atezolizumab plus bevacizumab group, and one patient (<1%) in the active surveillance group. Both atezolizumab and bevacizumab were discontinued because of adverse events in 29 patients (9%) who received atezolizumab plus bevacizumab. INTERPRETATION: Among patients at high risk of hepatocellular carcinoma recurrence following curative-intent resection or ablation, recurrence-free survival was improved in those who received atezolizumab plus bevacizumab versus active surveillance. To our knowledge, IMbrave050 is the first phase 3 study of adjuvant treatment for hepatocellular carcinoma to report positive results. However, longer follow-up for both recurrence-free and overall survival is needed to assess the benefit-risk profile more fully. FUNDING: F Hoffmann-La Roche/Genentech.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Adulto , Humanos , Bevacizumab/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/cirurgia , Conduta Expectante , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia
12.
Artigo em Inglês | MEDLINE | ID: mdl-38750867

RESUMO

BACKGROUND & AIMS: This study aims to reevaluate upper reference limit (URL) for alanine aminotransferase (ALT) by considering the changing epidemiology of major liver diseases. We employed histological and metabolic parameters in Asian living liver donors. METHODS: We performed a retrospective analysis of 5455 potential living liver donors from 2005 to 2019. Participants were screened for hepatitis B, C, HIV, and alcohol use. Histologically and metabolically healthy participants were assessed using the Prati criteria (body mass index <23 kg/m2, triglyceride ≤200 mg/dL, fasting glucose ≤105 mg/dL, total cholesterol ≤220 mg/dL). The updated ALT-URL was determined as the 95th percentile among participants without hepatic steatosis and who met the Prati criteria. RESULTS: The median age was 30 years, with a male predominance (66.2%). Among 5455 participants, 3162 (58.0%) showed no hepatic steatosis, with 1553 (49.1%) meeting both the criteria for no steatosis and the Prati criteria for metabolic health. The updated URL for ALT in these participants was 34 U/L for males and 22 U/L for females, which was significantly lower than conventionally accepted values. Using this revised ALT-URL, 72.8% of males with ALT levels ≥34 U/L and 55.0% of females with ALT levels ≥22 U/L showed signs of steatosis, whereas 32.7% of males and 22.2% of females met the criteria for metabolic syndrome. CONCLUSIONS: Our study provided the newly established reference intervals for ALT levels in a metabolically and histologically verified Asian population. The proposed URL for ALT are 34 U/L and 22 U/L for males and females, respectively.

13.
Biochem Biophys Res Commun ; 720: 150098, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38749190

RESUMO

Telomerase reverse transcriptase (TERT) not only upholds telomeric equilibrium but also plays a pivotal role in multiple non-canonical cellular mechanisms, particularly in the context of aging, cancer, and genomic stability. Though depletion of SIRT1 in mouse embryonic fibroblasts has demonstrated telomere shortening, the impact of SIRT1 on enabling TERT to regulate telomeric homeostasis remains enigmatic. Here, we reveal that SIRT1 directly interacts with TERT, and promotes the nuclear localization and stability of TERT. Reverse transcriptase (RT) domain of TERT and N-terminus of SIRT1 mainly participated in their direct interaction. TERT, concomitantly expressed with intact SIRT1, exhibits nuclear localization, whereas TERT co-expressed with N-terminal-deleted SIRT1 remains in the cytosol. Furthermore, overexpression of SIRT1 enhances the nuclear localization and protein stability of TERT, akin to overexpression of deacetylase-inactive SIRT1, whereas N-terminal-deleted SIRT1 has no effect on TERT. These findings suggest a novel regulatory role of SIRT1 for TERT through direct interaction. This interaction provides new insights into the fields of aging, cancer, and genome stability governed by TERT and SIRT1.


Assuntos
Sirtuína 1 , Telomerase , Animais , Humanos , Camundongos , Núcleo Celular/metabolismo , Estabilidade Enzimática , Células HEK293 , Ligação Proteica , Estabilidade Proteica , Sirtuína 1/metabolismo , Sirtuína 1/genética , Telomerase/metabolismo , Telomerase/genética
14.
Biochem Biophys Res Commun ; 726: 150306, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-38917634

RESUMO

The folate metabolism enzyme ALDH1L1 catalyzed 10-formyltetrahydrofolate to tetrahydrofolate and CO2. Non-small cell lung cancer cells (NSCLC) strongly express ALDH1L1. Gossypol binds to an allosteric site and disrupts the folate metabolism by preventing NADP+ binding. The Cryo-EM structures of tetrameric C-terminal aldehyde dehydrogenase human ALDH1L1 complex with gossypol were examined. Gossypol-bound ALDH1L1 interfered with NADP+ by shifting the allosteric site of the structural conformation, producing a closed-form NADP+ binding site. In addition, the inhibition activity of ALDH1L1 was targeted with gossypol in NSCLC. The gossypol treatment had anti-cancer effects on NSCLC by blocking NADPH and ATP production. These findings emphasize the structure characterizing ALDH1L1 with gossypol.


Assuntos
Gossipol , Humanos , Gossipol/química , Gossipol/farmacologia , Gossipol/metabolismo , NADP/metabolismo , NADP/química , Modelos Moleculares , Microscopia Crioeletrônica , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Aldeído Oxirredutases/metabolismo , Aldeído Oxirredutases/química , Ligação Proteica , Sítios de Ligação , Sítio Alostérico , Conformação Proteica , Linhagem Celular Tumoral , Oxirredutases atuantes sobre Doadores de Grupo CH-NH
15.
Biochem Biophys Res Commun ; 697: 149544, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38245927

RESUMO

T-cell immunoglobulin and mucin protein 3 (Tim-3), also known as Hepatitis A virus cellular receptor 2, has been discovered to have a negative regulatory effect on murine T-cell responses. Galectin-9 exhibits various biological effects, including cell aggregation, eosinophil chemoattraction, activation, and apoptosis, observed in murine thymocytes, T-cells, and human melanoma cells. Such approach demonstrated that Galectin-9 acts as a binding partner on Tim-3 and mediates the T-cell inhibitory effects. Tl-gal is a homologous protein to galectin-9, isolated from the adult stage of the canine gastrointestinal nematode parasite Toxascaris leonina. However, molecular mechanism between Tim-3 and galectin-9 is still remain unknown. Here, we describe the cryo-electron microscopy and X-ray structures and interactions of the Tim-3 and Tl-gal complex as well as their biochemical and biophysical characterization. In the structure, Ser46 residue of Tl-gal NCRD was bound to Asp25 residue of hTim-3. Compared to our previous study, the binding site of the complex is the same as the sugar binding site (the Ser46 residue) of Tl-gal. In addition, analysis of the complex structure revealed that the four Tl-gal molecules were in an open form packing and one mTim-3 peptide was bound to one Tl-gal molecule. These observations suggest that how Tl-gal binds hTim3 is essential to understanding the molecular mechanism for the Tim-3-galectin 9 interaction that regulates immune responses. This could potentially serve as a therapeutic target for inflammatory diseases.


Assuntos
Receptor Celular 2 do Vírus da Hepatite A , Toxascaris , Adulto , Camundongos , Animais , Humanos , Cães , Toxascaris/química , Toxascaris/metabolismo , Microscopia Crioeletrônica , Galectinas/metabolismo , Imunoglobulinas , Mucinas
16.
BMC Plant Biol ; 24(1): 527, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38858674

RESUMO

BACKGROUND: Angelica Gigas (Purple parsnip) is an important medicinal plant that is cultivated and utilized in Korea, Japan, and China. It contains bioactive substances especially coumarins with anti-inflammatory, anti-platelet aggregation, anti-cancer, anti-diabetic, antimicrobial, anti-obesity, anti-oxidant, immunomodulatory, and neuroprotective properties. This medicinal crop can be genetically improved, and the metabolites can be obtained by embryonic stem cells. In this context, we established the protoplast-to-plant regeneration methodology in Angelica gigas. RESULTS: In the present investigation, we isolated the protoplast from the embryogenic callus by applying methods that we have developed earlier and established protoplast cultures using Murashige and Skoog (MS) liquid medium and by embedding the protoplast in thin alginate layer (TAL) methods. We supplemented the culture medium with growth regulators namely 2,4-dichlorophenoxyaceticacid (2,4-D, 0, 0.75, 1.5 mg L- 1), kinetin (KN, 0, 0.5, and 1.0 mg L- 1) and phytosulfokine (PSK, 0, 50, 100 nM) to induce protoplast division, microcolony formation, and embryogenic callus regeneration. We applied central composite design (CCD) and response surface methodology (RSM) for the optimization of 2,4-D, KN, and PSK levels during protoplast division, micro-callus formation, and induction of embryogenic callus stages. The results revealed that 0.04 mg L- 1 2,4-D + 0.5 mg L- 1 KN + 2 nM PSK, 0.5 mg L- 1 2,4-D + 0.9 mg L- 1 KN and 90 nM PSK, and 1.5 mg L- 1 2,4-D and 1 mg L- 1 KN were optimum for protoplast division, micro-callus formation and induction embryogenic callus. MS basal semi-solid medium without growth regulators was good for the development of embryos and plant regeneration. CONCLUSIONS: This study demonstrated successful protoplast culture, protoplast division, micro-callus formation, induction embryogenic callus, somatic embryogenesis, and plant regeneration in A. gigas. The methodologies developed here are quite useful for the genetic improvement of this important medicinal plant.


Assuntos
Angelica , Reguladores de Crescimento de Plantas , Técnicas de Embriogênese Somática de Plantas , Protoplastos , Angelica/embriologia , Reguladores de Crescimento de Plantas/farmacologia , Técnicas de Embriogênese Somática de Plantas/métodos , Protoplastos/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos
17.
Breast Cancer Res Treat ; 205(3): 465-474, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38526688

RESUMO

PURPOSE: Central lumpectomy (CL) is a breast-conserving surgical (BCS) technique that involves excision of the nipple-areolar complex with breast tumor in centrally located breast cancers. We aimed to investigate the long-term clinical outcomes of CL in comparison with conventional BCS (cBCS). METHODS: Patient records who underwent BCS with clear resection margins for invasive breast cancer between 2004 and 2018 were retrospectively reviewed. Of the total 6,533 patients, 106 (1.6%) underwent CL. Median follow-up duration was 73.4 months. 1:3 propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were used to minimize selection bias. RESULTS: The CL group showed a significantly higher ipsilateral breast tumor recurrence (IBTR) rate than the cBCS group (10-year IBTR rate: 5.8% vs. 3.1%, p = 0.004), even after adjusting for other variables (hazard ratio (HR), 2.65; 95% confidence interval (CI), 1.07-6.60, p = 0.048). However, there were no significant differences observed in regional recurrence, distant metastasis, or overall survival rates between the two groups. Both PSM and IPTW analyses showed significantly higher IBTR in the CL group (PSM HR, 3.27; 95% CI, 0.94-11.36; p = 0.048 and IPTW HR, 4.66; 95%CI, 1.85-11.77; p < 0.001). Lastly, when analyzing 2,213 patients whose tumors were located within 3 cm of the nipple, the CL group showed a significantly higher IBTR than the cBCS group before and after PSM. CONCLUSION: CL was associated with a higher rate of IBTR compared to cBCS, while other survival outcomes were comparable. For centrally located tumors, CL may be considered for patients preferring breast preservation. However, higher risk for IBTR should be informed and careful surveillance may be necessary during the early post-operative follow-up periods.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Recidiva Local de Neoplasia , Pontuação de Propensão , Humanos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Mastectomia Segmentar/métodos , Feminino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/epidemiologia , Estudos Retrospectivos , Idoso , Adulto , Resultado do Tratamento , Seguimentos , Invasividade Neoplásica
18.
Small ; 20(9): e2304747, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37847909

RESUMO

All-solid-state lithium batteries (ASSLBs) are considered promising alternatives to current lithium-ion batteries that employ liquid electrolytes due to their high energy density and enhanced safety. Among various types of solid electrolytes, sulfide-based electrolytes are being actively studied, because they exhibit high ionic conductivity and high ductility, which enable good interfacial contacts in solid electrolytes without sintering at high temperatures. To improve the energy density of the sulfide-based ASSLBs, it is essential to increase the loading of active material in the composite cathode. In this study, the Ni-rich LiNix Coy Mn1-x-y O2 (NCM) materials are explored with different Ni content, particle size, and crystalline form to probe suitable cathode active materials for high-performance ASSLBs with high energy density. The results reveal that single-crystalline LiNi0.82 Co0.10 Mn0.08 O2 material with a small particle size exhibits the best cycling performance in the ASSLB assembled with a high mass loaded cathode (active mass loading: 26 mg cm-2 , areal capacity: 5.0 mAh cm-2 ) in terms of discharge capacity, capacity retention, and rate capability.

19.
J Synchrotron Radiat ; 31(Pt 1): 202-207, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37930256

RESUMO

Near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy is a powerful tool for identifying chemical bonding states at synchrotron radiation facilities. Advances in new materials require researchers in both academia and industry to measure tens to hundreds of samples during the available beam time on a synchrotron beamline, which is typically allocated to users. Automated measurement methods, along with analysis software, have been developed for beamlines. Automated measurements facilitate high-throughput experiments and accumulate vast amounts of measured spectral data. The analysis software supports various functions for analyzing the experimental data; however, these analysis methods are complicated, and learning them can be time-consuming. To process large amounts of spectral data, a new analysis software, dedicated to NEXAFS spectroscopy, that is easy to use and can provide results in a short time is desired. Herein, the development of Beagle is described, software calculating molecular orientation from NEXAFS spectroscopy data that can report results in a short time comparable with that required to measure one sample at the beamline. It was designed to progress in a single sequence from data loading to the printing of the results with a `click of a button'. The functions of the software include recognizing the dataset, correcting the background, normalizing the plot, calculating the electron yield and determining the molecular orientation. The analysis results can be saved as {\tt{.txt}} files (spectral data), {\tt{.pdf}} files (graphic images) and Origin files (spectral data and graphic images).

20.
Plant Physiol ; 191(3): 2012-2026, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36653329

RESUMO

Legumes acquire soil nutrients through nitrogen-fixing root nodules and lateral roots. To balance the costs and benefits of nodulation, legumes negatively control root nodule number by autoregulatory and hormonal pathways. How legumes simultaneously coordinate root nodule and lateral root development to procure nutrients remains poorly understood. In Medicago (Medicago truncatula), a subset of mature C-TERMINALLY ENCODED PEPTIDE (CEP) hormones can systemically promote nodule number, but all CEP hormones tested to date negatively regulate lateral root number. Here we showed that Medicago CEP7 produces a mature peptide, SymCEP7, that promotes nodulation from the shoot without compromising lateral root number. Rhizobial inoculation induced CEP7 in the susceptible root nodulation zone in a Nod factor-dependent manner, and, in contrast to other CEP genes, its transcription level was elevated in the ethylene signaling mutant sickle. Using mass spectrometry, fluorescence microscopy and expression analysis, we demonstrated that SymCEP7 activity requires the COMPACT ROOT ARCHITECTURE 2 receptor and activates the shoot-to-root systemic effector, miR2111. Shoot-applied SymCEP7 rapidly promoted nodule number in the pM to nM range at concentrations up to five orders of magnitude lower than effects mediated by root-applied SymCEP7. Shoot-applied SymCEP7 also promoted nodule number in White Clover (Trifolium repens) and Lotus (Lotus japonicus), which suggests that this biological function may be evolutionarily conserved. We propose that SymCEP7 acts in the Medicago shoot to counter balance the autoregulation pathways induced rapidly by rhizobia to enable nodulation without compromising lateral root growth, thus promoting the acquisition of nutrients other than nitrogen to support their growth.


Assuntos
Lotus , Medicago truncatula , Rhizobium , Trifolium , Nodulação/genética , Raízes de Plantas/metabolismo , Medicago truncatula/metabolismo , Rhizobium/fisiologia , Lotus/genética , Peptídeos/metabolismo , Trifolium/metabolismo , Hormônios/metabolismo , Nitrogênio/metabolismo , Nódulos Radiculares de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Simbiose , Regulação da Expressão Gênica de Plantas
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