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1.
Mol Cell ; 73(2): 314-324.e4, 2019 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-30527663

RESUMO

Macroautophagy/autophagy is a key catabolic recycling pathway that requires fine-tuned regulation to prevent pathologies and preserve homeostasis. Here, we report a new post-transcriptional pathway regulating autophagy involving the Pat1-Lsm (Lsm1 to Lsm7) mRNA-binding complex. Under nitrogen-starvation conditions, Pat1-Lsm binds a specific subset of autophagy-related (ATG) transcripts and prevents their 3' to 5' degradation by the exosome complex, leading to ATG mRNA stabilization and accumulation. This process is regulated through Pat1 dephosphorylation, is necessary for the efficient expression of specific Atg proteins, and is required for robust autophagy induction during nitrogen starvation. To the best of our knowledge, this work presents the first example of ATG transcript regulation via 3' binding factors and exosomal degradation.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Nitrogênio/deficiência , Proteínas de Ligação ao Cap de RNA/metabolismo , Estabilidade de RNA , RNA Fúngico/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Regiões 3' não Traduzidas , Proteínas Relacionadas à Autofagia/genética , Sítios de Ligação , Regulação Fúngica da Expressão Gênica , Humanos , Células Jurkat , Complexos Multiproteicos , Fosforilação , Ligação Proteica , Proteínas de Ligação ao Cap de RNA/genética , RNA Fúngico/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Transdução de Sinais
2.
Annu Rev Genet ; 52: 465-487, 2018 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-30208289

RESUMO

Advances in genome-wide sequence technologies allow for detailed insights into the complexity of RNA landscapes of organisms from all three domains of life. Recent analyses of archaeal transcriptomes identified interaction and regulation networks of noncoding RNAs in this understudied domain. Here, we review current knowledge of small, noncoding RNAs with important functions for the archaeal lifestyle, which often requires adaptation to extreme environments. One focus is RNA metabolism at elevated temperatures in hyperthermophilic archaea, which reveals elevated amounts of RNA-guided RNA modification and virus defense strategies. Genome rearrangement events result in unique fragmentation patterns of noncoding RNA genes that require elaborate maturation pathways to yield functional transcripts. RNA-binding proteins, e.g., L7Ae and LSm, are important for many posttranscriptional control functions of RNA molecules in archaeal cells. We also discuss recent insights into the regulatory potential of their noncoding RNA partners.


Assuntos
Archaea/genética , Interação Gene-Ambiente , RNA Arqueal/genética , Pequeno RNA não Traduzido/genética , Archaea/metabolismo , Regulação da Expressão Gênica em Archaea , RNA Arqueal/metabolismo , Transdução de Sinais/genética
3.
RNA ; 29(11): 1673-1690, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37562960

RESUMO

U7 snRNP is a multisubunit endonuclease required for 3' end processing of metazoan replication-dependent histone pre-mRNAs. In contrast to the spliceosomal snRNPs, U7 snRNP lacks the Sm subunits D1 and D2 and instead contains two related proteins, Lsm10 and Lsm11. The remaining five subunits of the U7 heptameric Sm ring, SmE, F, G, B, and D3, are shared with the spliceosomal snRNPs. The pathway that assembles the unique ring of U7 snRNP is unknown. Here, we show that a heterodimer of Lsm10 and Lsm11 tightly interacts with the methylosome, a complex of the arginine methyltransferase PRMT5, MEP50, and pICln known to methylate arginines in the carboxy-terminal regions of the Sm proteins B, D1, and D3 during the spliceosomal Sm ring assembly. Both biochemical and cryo-EM structural studies demonstrate that the interaction is mediated by PRMT5, which binds and methylates two arginine residues in the amino-terminal region of Lsm11. Surprisingly, PRMT5 also methylates an amino-terminal arginine in SmE, a subunit that does not undergo this type of modification during the biogenesis of the spliceosomal snRNPs. An intriguing possibility is that the unique methylation pattern of Lsm11 and SmE plays a vital role in the assembly of the U7 snRNP.


Assuntos
Ribonucleoproteína Nuclear Pequena U7 , Ribonucleoproteínas Nucleares Pequenas , Animais , Ribonucleoproteína Nuclear Pequena U7/química , Metilação , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Histonas/metabolismo , Arginina/química
4.
J Hepatol ; 81(4): 600-608, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38762169

RESUMO

BACKGROUND & AIMS: The clinical significance of change in liver stiffness measurement (LSM) by vibration-controlled transient elastography (VCTE) in patients with non-alcoholic fatty liver disease (NAFLD) is not well-understood. We prospectively defined rates of progression to and regression from LSM-defined compensated advanced chronic liver disease (cACLD) and their associations with liver-related events (LREs). METHODS: Participants in the NASH Clinical Research Network-led NAFLD Database 2 and 3 studies were included. Progression to cACLD was defined as reaching LSM ≥10 kPa in participants with LSM <10 kPa on initial VCTE; regression from cACLD was defined as reaching LSM <10 kPa in participants with baseline LSM ≥10 kPa. LREs were defined as liver-related death, liver transplant, hepatocellular carcinoma, MELD >15, development of varices, or hepatic decompensation. Univariate and multivariable interval-censored Cox regression analyses were used to compare the cumulative LRE probability by LSM progression and regression status. RESULTS: In 1,403 participants, 89 LREs developed over a mean follow-up of 4.4 years, with an annual incidence rate for LREs of 1.5 (95% CI 1.2-1.8). In participants at risk, progression to LSM ≥10 or ≥15 kPa occurred in 29% and 17%, respectively, whereas regression to LSM <10 or <15 kPa occurred in 44% and 49%, respectively. Progressors to cACLD (≥10 kPa) experienced a higher cumulative LRE rate vs. non-progressors (16% vs. 4%, adjusted hazard ratio 4.0; 95% (1.8-8.9); p <0.01). Regressors from cACLD (to LSM <10 kPa) experienced a lower LRE rate than non-regressors (7% vs. 32%, adjusted hazard ratio 0.25; 95% CI 0.10-0.61; p <0.01). CONCLUSIONS: Change in LSM over time is independently and bi-directionally associated with risk of LRE and is a non-invasive surrogate for clinical outcomes in patients with NAFLD. IMPACT AND IMPLICATIONS: The prognostic value of change in LSM in patients with NAFLD is not well understood. In this large prospective study of patients with NAFLD and serial vibration-controlled transient elastography exams, baseline and dynamic changes in LSM were associated with the risk of developing liver-related events. LSM is a useful non-invasive surrogate of clinical outcomes in patients with NAFLD.


Assuntos
Progressão da Doença , Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Técnicas de Imagem por Elasticidade/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fígado/diagnóstico por imagem , Fígado/fisiopatologia , Fígado/patologia , Adulto , Fatores de Risco , Idoso
5.
Gastroenterology ; 165(4): 1041-1052, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37442301

RESUMO

BACKGROUND & AIMS: Liver stiffness measurements (LSMs) provide an opportunity to monitor liver disease progression and regression noninvasively. We aimed to determine the prognostic relevance of LSM dynamics over time for liver-related events and death in patients with chronic liver disease. METHODS: Patients with chronic liver disease undergoing 2 or more reliable LSMs at least 180 days apart were included in this retrospective cohort study and stratified at baseline (BL) as nonadvanced chronic liver disease (non-ACLD, BL-LSM < 10 kPa), compensated ACLD (cACLD; BL-LSM ≥ 10 kPa), and decompensated ACLD. Data on all consecutive LSMs and clinical outcomes were collected. RESULTS: There were 2508 patients with 8561 reliable LSMs (3 per patient; interquartile range, 2-4) included: 1647 (65.7%) with non-ACLD, 757 (30.2%) with cACLD, and 104 (4.1%) with decompensated ACLD. Seven non-ACLD patients (0.4%) and 83 patients with cACLD (10.9%) developed hepatic decompensation (median follow-up, 71 months). A 20% increase in LSM at any time was associated with an approximately 50% increased risk of hepatic decompensation (hazard ratio, 1.58; 95% CI, 1.41-1.79; P < .001) and liver-related death (hazard ratio, 1.45; 95% CI, 1.28-1.68; P < .001) in patients with cACLD. LSM dynamics yielded a high accuracy to predict hepatic decompensation in the following 12 months (area under the receiver operating characteristics curve = 0.933). The performance of LSM dynamics was numerically better than dynamics in Fibrosis-4 score (0.873), Model for End-Stage Liver Disease (0.835), and single time-point LSM (BL-LSM: 0.846; second LSM: 0.880). Any LSM decrease to <20 kPa identified patients with cACLD with a substantially lower risk of hepatic decompensation (hazard ratio, 0.13; 95% CI, 0.07-0.24). If reliable, LSM also confers prognostic information in decompensated ACLD. CONCLUSIONS: Repeating LSM enables an individual and updated risk assessment for decompensation and liver-related mortality in ACLD.


Assuntos
Técnicas de Imagem por Elasticidade , Doença Hepática Terminal , Hepatopatias , Humanos , Estudos Retrospectivos , Doença Hepática Terminal/complicações , Índice de Gravidade de Doença , Hepatopatias/patologia , Fígado/diagnóstico por imagem , Fígado/patologia , Medição de Risco , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/etiologia
6.
Liver Int ; 44(8): 1872-1885, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38573034

RESUMO

BACKGROUND & AIMS: There is a need to reduce the screen failure rate (SFR) in metabolic dysfunction-associated steatohepatitis (MASH) clinical trials (MASH+F2-3; MASH+F4) and identify people with high-risk MASH (MASH+F2-4) in clinical practice. We aimed to evaluate non-invasive tests (NITs) screening approaches for these target conditions. METHODS: This was an individual participant data meta-analysis for the performance of NITs against liver biopsy for MASH+F2-4, MASH+F2-3 and MASH+F4. Index tests were the FibroScan-AST (FAST) score, liver stiffness measured using vibration-controlled transient elastography (LSM-VCTE), the fibrosis-4 score (FIB-4) and the NAFLD fibrosis score (NFS). Area under the receiver operating characteristics curve (AUROC) and thresholds including those that achieved 34% SFR were reported. RESULTS: We included 2281 unique cases. The prevalence of MASH+F2-4, MASH+F2-3 and MASH+F4 was 31%, 24% and 7%, respectively. Area under the receiver operating characteristics curves for MASH+F2-4 were .78, .75, .68 and .57 for FAST, LSM-VCTE, FIB-4 and NFS. Area under the receiver operating characteristics curves for MASH+F2-3 were .73, .67, .60, .58 for FAST, LSM-VCTE, FIB-4 and NFS. Area under the receiver operating characteristics curves for MASH+F4 were .79, .84, .81, .76 for FAST, LSM-VCTE, FIB-4 and NFS. The sequential combination of FIB-4 and LSM-VCTE for the detection of MASH+F2-3 with threshold of .7 and 3.48, and 5.9 and 20 kPa achieved SFR of 67% and sensitivity of 60%, detecting 15 true positive cases from a theoretical group of 100 participants at the prevalence of 24%. CONCLUSIONS: Sequential combinations of NITs do not compromise diagnostic performance and may reduce resource utilisation through the need of fewer LSM-VCTE examinations.


Assuntos
Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Humanos , Técnicas de Imagem por Elasticidade/métodos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Curva ROC , Fígado/patologia , Fígado/diagnóstico por imagem , Cirrose Hepática/diagnóstico , Biópsia , Programas de Rastreamento/métodos
7.
Liver Int ; 44(7): 1700-1714, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38558221

RESUMO

BACKGROUND & AIMS: The predictors of progression from steatosis to more advanced stages of metabolic dysfunction-associated steatotic liver disease (MASLD) remain unclear. We evaluated the association between the quantity of hepatic steatosis and longitudinal changes in liver stiffness measurements (LSMs) using magnetic resonance elastography (MRE) in patients with MASLD. METHODS: We retrospectively analysed patients with MASLD who underwent at least two serial MRE and magnetic resonance imaging-based proton density fat fraction (MRI-PDFF) examinations at least 1 year apart. Fine-Gray competitive proportional hazard regression was used to identify LSM progression and regression factors. RESULTS: A total of 471 patients were enrolled. Factors linked to LSM progression were steatosis grade 3 (MRI-PDFF ≥17.1%, adjusted hazard ratio [aHR] 2.597; 95% confidence interval [CI] 1.483-4.547) and albumin-bilirubin grade 2 or 3 (aHR 2.790; 95% CI 1.284-6.091), while the only factor linked to LSM regression was % decrease rate of MRI-PDFF ≥5% (aHR 2.781; 95% CI 1.584-4.883). Steatosis grade 3 correlated with a higher incidence rate of LSM progression than steatosis grade 1 (MRI-PDFF <11.3%) in patients with LSM stage 0 (<2.5 kilopascal [kPa]), and a % annual decrease rate of MRI-PDFF ≥5% correlated with a higher incidence rate of LSM regression than that of MRI-PDFF >-5% and <5% in patients with LSM stage 1 or 2-4 (≥2.5 kPa). CONCLUSIONS: Severe hepatic steatosis was linked to significant LSM progression in patients with MASLD and low LSM (<2.5 kPa).


Assuntos
Progressão da Doença , Técnicas de Imagem por Elasticidade , Fígado Gorduroso , Fígado , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Fígado/patologia , Fígado/diagnóstico por imagem , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/patologia , Idoso , Adulto , Índice de Gravidade de Doença , Modelos de Riscos Proporcionais , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/patologia
8.
Scand J Gastroenterol ; 59(10): 1184-1191, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39219192

RESUMO

BACKGROUND: Hepatitis C virus (HCV) is a major cause of chronic liver disease, in which liver stiffness increases. Liver stiffness measurements (LSM) are therefore essential in diagnosing liver diseases and predicting disease development. The study objective was to perform a comprehensive prospective assessment of the liver before, after and 4 years after treatment for HCV, including an assessment of the long-term outcome of fibrosis, steatosis and inflammation. METHODS AND FINDINGS: Patients eligible for HCV treatment were included prospectively in 2018 (n = 47). Liver stiffness was measured using transient elastography and 2D shear-wave elastography (SWE). Blood tests, B-mode ultrasound (US) and SWE, were performed before, after (end of treatment [EOT]), 3 months after (EOT3) and 4 years after treatment (4Y). At the final visit, we added attenuation imaging and shear-wave dispersion slope (SWDS) measurements to assess steatosis and inflammation. Three months after treatment, the sustained virologic response rate was 93%. The median liver stiffness for baseline, EOT, EOT3 and 4Y was 8.1, 5.9, 5.6 and 6.3 kPa, respectively. There was a significant reduction in liver stiffness from baseline to EOT, and from EOT to EOT3. After 4 years, the mean attenuation coefficient (AC) was 0.58 dB/cm/MHz, and the mean SWDS value was 14.3 (m/s)/kHz. CONCLUSION: The treatment for HCV was highly effective. Measurements of liver stiffness decreased significantly after treatment and remained low after 4 years. AC measurements indicated low levels of liver steatosis. Shear-wave dispersion values indicated inflammation of the liver, but the clinical implication is undetermined and should be explored in larger studies.Clinicaltrials.gov: NCT03434470. ABBREVIATIONS: AC: attenuation coefficient; APRI: aspartate aminotransferase to platelet ratio index; ATI: attenuation imaging; cACLD: compensated advanced chronic liver disease; CAP: controlled attenuation parameter; FIB-4: Fibrosis-4 Index for liver fibrosis; HCC: hepatocellular carcinoma; LSM: liver stiffness measurement; NAFLD: non-alcoholic fatty liver disease; NASH: non-alcoholic steatohepatitis; SWDS: shear-wave dispersion slope; SWE: shear-wave elastography; US: ultrasound.


Assuntos
Antivirais , Técnicas de Imagem por Elasticidade , Hepatite C Crônica , Cirrose Hepática , Fígado , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Prospectivos , Antivirais/uso terapêutico , Seguimentos , Fígado/diagnóstico por imagem , Fígado/patologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/complicações , Hepatite C Crônica/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Idoso , Adulto , Resposta Viral Sustentada , Fígado Gorduroso/diagnóstico por imagem
9.
Dig Dis Sci ; 69(4): 1496-1506, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38376788

RESUMO

BACKGROUND & AIMS: Concurrent hepatic steatosis has diverse effects on chronic hepatitis B (CHB), however the combined effects of metabolic dysfunction-associated steatotic liver disease (MASLD) and CHB on liver fibrosis progression remains unclear. The primary aim of this study was to utilize serial fibrosis measurements to compare the dynamic change in fibrosis in CHB patients with/without concurrent MASLD. The secondary aim was to investigate factors associated with steatosis development and regression in CHB patients. METHODS: This was a retrospective cohort study of all non-cirrhotic CHB patients identified from 1/1/2011 to 31/12/2016. Hepatic steatosis was diagnosed by ultrasound. Fibrosis markers included liver stiffness (LSM) by transient elastography, APRI and FIB-4. General linear mixed effects modelling was used to fit polynomial and linear estimates. RESULTS: Of 810 CHB patients (n = 2,373 LSM measurements; median age 44.4y; 48% male; 24% HBeAg positive), 14% had concurrent MASLD. LSM was higher at baseline but decreased in MASLD patients over time, while LSM remained stable in non-MASLD patients, such that all patients had similar LSM beyond 4-5 years. MASLD patients had lower APRI compared to non-MASLD patients, which was predominately due to a higher platelet count and higher ALT over time. There was substantial discordance between LSM, APRI and FIB-4. Baseline BMI was the only factor that predicted steatosis development and regression. CONCLUSIONS: We found no evidence of an association between concurrent MASLD and fibrosis progression amongst CHB patients without baseline advanced liver disease. APRI and FIB-4 may have reduced accuracy in MASLD patients.


Assuntos
Técnicas de Imagem por Elasticidade , Fígado Gorduroso , Hepatite B Crônica , Hepatopatia Gordurosa não Alcoólica , Humanos , Masculino , Adulto , Feminino , Hepatite B Crônica/complicações , Estudos Retrospectivos , Cirrose Hepática/diagnóstico , Fígado Gorduroso/complicações , Hepatopatia Gordurosa não Alcoólica/complicações
10.
Cell Mol Life Sci ; 80(9): 247, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37578641

RESUMO

Controlled mRNA storage and stability is essential for oocyte meiosis and early embryonic development. However, how to regulate mRNA storage and stability in mammalian oogenesis remains elusive. Here we showed that LSM14B, a component of membraneless compartments including P-body-like granules and mitochondria-associated ribonucleoprotein domain (MARDO) in germ cell, is indispensable for female fertility. To reveal loss of LSM14B disrupted primordial follicle assembly and caused mRNA reduction in non-growing oocytes, which was concomitant with the impaired assembly of P-body-like granules. 10× Genomics single-cell RNA-sequencing and immunostaining were performed. Meanwhile, we conducted RNA-seq analysis of GV-stage oocytes and found that Lsm14b deficiency not only impaired the maternal mRNA accumulation but also disrupted the translation in fully grown oocytes, which was closely associated with dissolution of MARDO components. Moreover, Lsm14b-deficient oocytes reassembled a pronucleus containing decondensed chromatin after extrusion of the first polar body, through compromising the activation of maturation promoting factor, while the defects were restored via WEE1/2 inhibitor. Together, our findings reveal that Lsm14b plays a pivotal role in mammalian oogenesis by specifically controlling of oocyte mRNA storage and stability.


Assuntos
Oócitos , Oogênese , Animais , Feminino , RNA Mensageiro/genética , Oogênese/genética , Folículo Ovariano , Meiose/genética , Fertilidade/genética , Mamíferos
11.
J Clin Densitom ; 27(2): 101479, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38447349

RESUMO

OBJECTIVE: Hyperprolactinemia has negative impacts on metabolism and musculoskeletal health. In this study, individuals with active prolactinoma were evaluated for nonalcoholic fatty liver disease (NAFLD) and musculoskeletal health, which are underemphasized in the literature. METHODS: Twelve active prolactinoma patients and twelve healthy controls matched by age, gender, and BMI were included. Magnetic resonance imaging-proton density fat fraction (MRI-PDFF) was used to evaluate hepatic steatosis and magnetic resonance elastography (MRE) to evaluate liver stiffness measurement (LSM). Abdominal muscle mass, and vertebral MRI-PDFF was also evaluated with MRI. Body compositions were evaluated by dual energy X-ray absorptiometry (DXA). The skeletal muscle quality (SMQ) was classified as normal, low and weak by using "handgrip strength/appendicular skeletal muscle mass (HGS/ASM)" ratio based on the cut-off values previously stated in the literature. RESULTS: Prolactin, HbA1c and CRP levels were higher in prolactinoma patients (p<0.001, p=0.033 and p=0.035, respectively). The median MRI-PDFF and MRE-LSM were 3.0% (2.01-15.20) and 2.22 kPa (2.0-2.5) in the prolactinoma group and 2.5% (1.65-10.00) and 2.19 kPa (1.92-2.54) in the control group, respectively and similiar between groups. In prolactinoma patients, liver MRI-PDFF showed a positive and strong correlation with the duration of disease and traditional risk factors for NAFLD. Total, vertebral and pelvic bone mineral density was similar between groups, while vertebral MRI-PDFF tended to be higher in prolactinoma patients (p=0.075). Muscle mass and strength parameters were similar between groups, but HGS/ASM tended to be higher in prolactinoma patients (p=0.057). Muscle mass was low in 33.3% of prolactinoma patients and 66.6 of controls. According to SMQ, all prolactinoma patients had normal SMQ, whereas 66.6% of the controls had normal SMQ. CONCLUSION: Prolactinoma patients demonstrated similar liver MRI-PDFF and MRE-LSM to controls despite their impaired metabolic profile and lower gonadal hormone levels. Hyperprolactinemia may improve muscle quality in prolactinoma patients despite hypogonadism.


Assuntos
Absorciometria de Fóton , Imageamento por Ressonância Magnética , Músculo Esquelético , Hepatopatia Gordurosa não Alcoólica , Neoplasias Hipofisárias , Prolactinoma , Humanos , Projetos Piloto , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiopatologia , Estudos de Casos e Controles , Prolactinoma/diagnóstico por imagem , Prolactinoma/fisiopatologia , Prolactinoma/complicações , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/fisiopatologia , Técnicas de Imagem por Elasticidade , Força da Mão , Fígado/diagnóstico por imagem , Fígado/patologia , Hemoglobinas Glicadas , Densidade Óssea , Prolactina/sangue , Composição Corporal
12.
Int J Mol Sci ; 25(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38203750

RESUMO

The Sm protein superfamily includes Sm, like-Sm (Lsm), and Hfq found in the Eukarya, Archaea, and Bacteria domains. Archaeal Lsm proteins have been shown to bind sRNAs and are probably involved in various cellular processes, suggesting a similar function in regulating sRNAs by Hfq in bacteria. Moreover, archaeal Lsm proteins probably represent the ancestral Lsm domain from which eukaryotic Sm proteins have evolved. In this work, Haloferax mediterranei was used as a model organism because it has been widely used to investigate the nitrogen cycle and its regulation in Haloarchaea. Predicting this protein's secondary and tertiary structures has resulted in a three-dimensional model like the solved Lsm protein structure of Archaeoglobus fulgidus. To obtain information on the oligomerization state of the protein, homologous overexpression and purification by means of molecular exclusion chromatography have been performed. The results show that this protein can form hexameric complexes, which can aggregate into 6 or 12 hexameric rings depending on the NaCl concentration and without RNA. In addition, the study of transcriptional expression via microarrays has allowed us to obtain the target genes regulated by the Lsm protein under nutritional stress conditions: nitrogen or carbon starvation. Microarray analysis has shown the first universal stress proteins (USP) in this microorganism that mediate survival in situations of nitrogen deficiency.


Assuntos
Proteínas Arqueais , Haloferax mediterranei , Haloferax mediterranei/genética , Proteínas Arqueais/genética , Proteínas de Choque Térmico , Archaea , Nitrogênio
13.
Genes Chromosomes Cancer ; 62(1): 52-56, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35932215

RESUMO

Extraskeletal myxoid chondrosarcoma (EMC) is a rare soft tissue neoplasm of uncertain lineage characterized by the pathognomonic rearrangement of the NR4A3 gene, which in most cases is fused with EWSR1. Other NR4A3 fusion partners have been described, namely TAF15, FUS, TCF12, and TGF. Some studies suggest that EMCs with non-EWSR1 variant fusion are associated with high-grade morphology and worst clinical behavior compared to EWSR1::NR4A3 tumors, supporting the potential significance of particular fusion variant in EMC. We report a case of a 34-year-old male who presented with calf EMC and subsequently developed a slowly progressive metastatic disease 3 years after diagnosis. Whole-transcriptome analysis with total RNA sequencing enabled identification of a novel fusion transcript LSM14A::NR4A3, expanding the molecular spectrum of EMC.


Assuntos
Condrossarcoma , Receptores de Esteroides , Neoplasias de Tecidos Moles , Masculino , Humanos , Adulto , Receptores dos Hormônios Tireóideos/genética , Receptores de Esteroides/genética , Proteínas de Fusão Oncogênica/genética , Condrossarcoma/patologia , Neoplasias de Tecidos Moles/genética , Proteínas de Ligação a DNA
14.
Am J Physiol Cell Physiol ; 324(5): C1007-C1016, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36939200

RESUMO

MicroRNAs play a critical role in bone marrow mesenchymal stem cell (MSC) chondrogenesis and regulate the progression of joint regeneration in osteoarthritis. Our previous research confirmed that miR146a relieves osteoarthritis by modulating cartilage homeostasis. However, few studies have revealed the relationship between miR146a and the chondrogenesis of MSCs, and the exact mechanisms remain unclear. This study aimed to determine the function of miR146a in the chondrogenic differentiation of MSCs and the potential mechanisms involved. MiR146a expression increased during chondrogenesis. MiR146a knockout (KO) led to the increased chondrogenesis of MSCs compared to that in wild-type (WT) MSCs, whereas the overexpression of miR146a by mimics resulted in the decreased chondrogenesis of MSCs, as determined by the mRNA expression of collagen, type II, alpha 1 (COL2A1), aggrecan, cartilage oligomeric matrix protein (COMP), and matrix metallopeptidase 13 (MMP13). Furthermore, cartilage defects could be treated better when injected with spheres induced from miR146aKO MSCs than from WT MSCs, indicating that miR146a inhibits chondrogenesis in vivo. In addition, based on miRNA-mRNA prediction analysis and a dual-luciferase reporter assay, we observed that the deletion of miR146a led to the increased expression of Lsm11 during chondrogenesis and demonstrated that miR146a targeted Lsm11 by binding to its 3'-untranslated region (UTR) and inhibited its translation. The inhibition of Lsm11 by silencing RNA (siRNA) reversed the increased ability of chondrogenesis by knocking out miR146a both in vivo and in vitro, suggesting that miR146a inhibits chondrogenesis by directly inhibiting Lsm11 in MSCs, which may be a novel target for treating osteoarthritis.


Assuntos
Células-Tronco Mesenquimais , MicroRNAs , Osteoartrite , Humanos , Células da Medula Óssea/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Condrócitos/metabolismo , Condrogênese/genética , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo
15.
Mol Carcinog ; 62(12): 1902-1917, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37642290

RESUMO

Abnormal RNA N7-methylguanosine (m7G) modification is known to contribute to effects on tumor occurrence and development. Nevertheless, the mechanisms of its function in immunoregulation, tumor microenvironment (TME) modulation, and tumor promotion remain largely unknown. A series of computer-aided bioinformatic analyses were conducted based on transcriptomic, single-cell sequence, and spatial transcriptomic data to determine the m7G modification patterns in head and neck squamous cell carcinoma (HNSCC). Consensus clustering approach was employed according to the expressions of 33 m7G regulators. ESTIMATE, CIBERSORT, and single sample gene set enrichment analysis algorithms were adopted to investigate the immune cell infiltration features. A prognostic model named m7Gscore was established. Seurat, SingleR, and Monocle2 were used to analyze the single-cell sequence profiling. STUtility was used to integrate multiple spatial transcriptomic datasets. Quantitative reverse transcription polymerase chain reaction, transwell, and wound-healing assay were performed to verify the oncogenes. Here, three different m7G modification patterns were highlighted in HNSCC patients, which were also related to various clinical manifestations and three representative immunophenotypes: immune-excluded, immune-desert, and inflamed, separately. Patients with lower m7Gscore were highlighted by higher immune cell infiltrations, better overall survival rates, lesser tumor mutation burden (TMB), lower sensitivities to target inhibitors therapies, and better immunotherapeutic response. Moreover, DCPS, EIF4E, EIF4E2, LSM1, NCBP2, NUDT1, and NUDT5 were identified to play critical roles in T-cell differentiation. Knockdown of LSM1/NUDT5 could restrain the malignancy of HNSCC cells. Collectively, quantitative assessment of m7G modification patterns in individual HNSCC patients could contribute to identifying more efficient immunotherapeutic approaches and improve the clinical outcome of HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Oncogenes , Humanos , Metilação , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , RNA , Neoplasias de Cabeça e Pescoço/genética , Microambiente Tumoral/genética
16.
New Phytol ; 239(2): 506-517, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37194956

RESUMO

Volume and surface area of chloroplasts and surface area of plasmodesmata pit fields are presented for two C4 species, maize and sugarcane, with respect to cell surface area and cell volume. Serial block face scanning electron microscopy (SBF-SEM) and confocal laser scanning microscopy with the Airyscan system (LSM) were used. Chloroplast size estimates were much faster and easier using LSM than with SBF-SEM; however, the results were more variable than SBF-SEM. Mesophyll cells were lobed where chloroplasts were located, facilitating cell-to-cell connections while allowing for greater intercellular airspace exposure. Bundle sheath cells were cylindrical with chloroplasts arranged centrifugally. Chloroplasts occupied c. 30-50% of mesophyll cell volume, and 60-70% of bundle sheath cell volume. Roughly 2-3% of each cell surface area was covered by plasmodesmata pit fields for both bundle sheath and mesophyll cells. This work will aid future research to develop SBF-SEM methodologies with the aim to better understand the effect of cell structure on C4 photosynthesis.


Assuntos
Saccharum , Zea mays , Zea mays/metabolismo , Plasmodesmos/metabolismo , Cloroplastos/metabolismo , Folhas de Planta/metabolismo , Fotossíntese , Células do Mesofilo/metabolismo , Grão Comestível
17.
J Med Virol ; 95(7): e28943, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37436779

RESUMO

A proportion of chronic hepatitis B virus (HBV) carriers with normal alanine transaminase (ALT) present with significant liver histological changes (SLHC). To construct a noninvasive nomogram model to identify SLHC in chronic HBV carriers with different upper limits of normal (ULNs) for ALT. The training cohort consisted of 732 chronic HBV carriers who were stratified into four sets according to different ULNs for ALT: chronic HBV carriers I, II, III, and IV. The external validation cohort comprised 277 chronic HBV carriers. Logistic regression and least absolute shrinkage and selection operator analyses were applied to develop a nomogram model to predict SLHC. A nomogram model-HBGP (based on hepatitis B surface antigen, gamma-glutamyl transpeptidase, and platelet count) demonstrated good performance in diagnosing SLHC with area under the curve (AUCs) of 0.866 (95% confidence interval [CI]: 0.839-0.892) and 0.885 (95% CI: 0.845-0.925) in the training and validation cohorts, respectively. Furthermore, HBGP displayed high diagnostic values for SLHC with AUCs of 0.866 (95% CI: 0.839-0.892), 0.868 (95% CI: 0.838-0.898), 0.865 (95% CI: 0.828-0.901), and 0.853 (95% CI: 0.798-0.908) in chronic HBV carriers I, II, III, and IV, respectively. Additionally, HBGP showed greater ability in predicting SLHC compared with the existing predictors. HBGP has shown high predictive performance for SLHC, and thus may lead to an informed decision on the initiation of antiviral treatment.


Assuntos
Hepatite B Crônica , Humanos , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/patologia , Nomogramas , Vírus da Hepatite B/genética , Cirrose Hepática/diagnóstico , Alanina Transaminase , DNA Viral , Antígenos E da Hepatite B
18.
Glob Chang Biol ; 29(15): 4440-4452, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37303068

RESUMO

Dynamic Global Vegetation Models (DGVMs) provide a state-of-the-art process-based approach to study the complex interplay between vegetation and its physical environment. For example, they help to predict how terrestrial plants interact with climate, soils, disturbance and competition for resources. We argue that there is untapped potential for the use of DGVMs in ecological and ecophysiological research. One fundamental barrier to realize this potential is that many researchers with relevant expertize (ecology, plant physiology, soil science, etc.) lack access to the technical resources or awareness of the research potential of DGVMs. Here we present the Land Sites Platform (LSP): new software that facilitates single-site simulations with the Functionally Assembled Terrestrial Ecosystem Simulator, an advanced DGVM coupled with the Community Land Model. The LSP includes a Graphical User Interface and an Application Programming Interface, which improve the user experience and lower the technical thresholds for installing these model architectures and setting up model experiments. The software is distributed via version-controlled containers; researchers and students can run simulations directly on their personal computers or servers, with relatively low hardware requirements, and on different operating systems. Version 1.0 of the LSP supports site-level simulations. We provide input data for 20 established geo-ecological observation sites in Norway and workflows to add generic sites from public global datasets. The LSP makes standard model experiments with default data easily achievable (e.g., for educational or introductory purposes) while retaining flexibility for more advanced scientific uses. We further provide tools to visualize the model input and output, including simple examples to relate predictions to local observations. The LSP improves access to land surface and DGVM modelling as a building block of community cyberinfrastructure that may inspire new avenues for mechanistic ecosystem research across disciplines.


Assuntos
Clima , Ecossistema , Humanos , Fenômenos Fisiológicos Vegetais , Software , Plantas
19.
Liver Int ; 43(12): 2604-2610, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37724792

RESUMO

BACKGROUND AND AIMS: Several studies reported an association between liver stiffness measurement (LSM) obtained through vibration-controlled transient elastography (VCTE) and all-cause mortality in patients with nonalcoholic fatty liver disease (NAFLD). The objective of this systematic review and meta-analysis was to summarize available evidence on the nature and magnitude of this association. METHODS: We systematically searched PubMed-MEDLINE and Scopus up to April 2023 for observational cohort studies in which LSM was measured with VCTE in patients with NAFLD or in general population settings, with a follow-up ≥1 year and with available data on all-cause mortality. Measures of association from individual studies were meta-analysed using random effects models. Of the 517 titles initially scrutinized, we included seven studies with data on 18 771 participants (47.1% male) and a mean follow-up of 3.6 years. We included effect estimates obtained in the models with the highest degree of adjustment for potential confounders available in each study. RESULTS: When analysed as a categorical variable based on specific LSM cut-offs, liver fibrosis was associated with an increased risk of all-cause death (HR 2.10, 95% CI 1.56-2.83; test for overall effect z = 4.919, p < 0.001). Results were consistent when LSM was considered as a continuous variable (HR for 1 kPa increase: 1.03, 95% CI 1.01-1.05; test for overall effect z = 3.341, p = 0.001). There was borderline significant heterogeneity among the studies (I2 = 50.2% and I2 = 66.7% in the two analyses, respectively). No significant publication bias was detected by funnel plot analysis and Egger's and Begg's tests. CONCLUSION: The present meta-analysis indicates that LSM, as a proxy of liver fibrosis, is independently and directly associated with a higher mortality risk in patients with NAFLD.


Assuntos
Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Humanos , Masculino , Feminino , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Cirrose Hepática/complicações , Técnicas de Imagem por Elasticidade/métodos , Fígado/diagnóstico por imagem , Fígado/patologia
20.
Pharmacol Res ; 198: 107008, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37995895

RESUMO

LSM1 is part of the cytoplasmic protein complex Lsm1-7-Pat1 and is likely involved in pre-mRNA degradation by aiding U4/U6 snRNP formation. More research is needed to uncover LSM1's potential in breast cancer (BRCA) clinical pathology, the tumor immune microenvironment, and precision oncology. We discovered LSM1 as a diagnostic marker for advanced BRCA with poor survival, using a multi-omics approach. We studied LSM1 expression across BRCA regions and its link to immune cells through various methods, including spatial transcriptomics and single-cell RNA-sequencing. We also examined how silencing LSM1 affects mitochondrial function and energy metabolism in the tumor environment. These findings were confirmed using 54 BRCA patient biopsies and tissue microarrays. Immunofluorescence and bioinformatics assessed LSM1's connection to clinicopathological features and prognosis. This study uncovers gene patterns linked to breast cancer, with LSM1 linked to macrophage energy processes. Silencing LSM1 in breast cancer cells disrupts mitochondria and energy metabolism. Spatial analysis aligns with previous results, showing LSM1's connection to macrophages. Biopsies confirm LSM1 elevation in advanced breast cancer with increased macrophage presence. To summarize, LSM1 changes may drive BRCA progression, making it a potential diagnostic and prognostic marker. It also influences energy metabolism and the tumor's immune environment during metastasis, showing promise for precision medicine and drug screening in BRCA.


Assuntos
Neoplasias da Mama , Proteínas de Saccharomyces cerevisiae , Humanos , Feminino , Proteínas de Ligação a RNA/genética , Proteínas de Ligação ao Cap de RNA/genética , Proteínas de Ligação ao Cap de RNA/metabolismo , Saccharomyces cerevisiae/genética , RNA Mensageiro/metabolismo , Neoplasias da Mama/genética , Macrófagos Associados a Tumor/metabolismo , Medicina de Precisão , Microambiente Tumoral , Proteínas Proto-Oncogênicas/metabolismo
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