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1.
Hum Mol Genet ; 32(1): 104-121, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-35925837

RESUMEN

Eukaryotic RNA polymerase I (Pol I) products play fundamental roles in ribosomal assembly, protein synthesis, metabolism and cell growth. Abnormal expression of both Pol I transcription-related factors and Pol I products causes a range of diseases, including ribosomopathies and cancers. However, the factors and mechanisms governing Pol I-dependent transcription remain to be elucidated. Here, we report that transcription factor IIB-related factor 1 (BRF1), a subunit of transcription factor IIIB required for RNA polymerase III (Pol III)-mediated transcription, is a nucleolar protein and modulates Pol I-mediated transcription. We showed that BRF1 can be localized to the nucleolus in several human cell types. BRF1 expression correlates positively with Pol I product levels and tumour cell growth in vitro and in vivo. Pol III transcription inhibition assays confirmed that BRF1 modulates Pol I-directed transcription in an independent manner rather than through a Pol III product-to-45S pre-rRNA feedback mode. Mechanistically, BRF1 binds to the Pol I transcription machinery components and can be recruited to the rDNA promoter along with them. Additionally, alteration of BRF1 expression affects the recruitment of Pol I transcription machinery components to the rDNA promoter and the expression of TBP and TAF1A. These findings indicate that BRF1 modulates Pol I-directed transcription by controlling the expression of selective factor 1 subunits. In summary, we identified a novel role of BRF1 in Pol I-directed transcription, suggesting that BRF1 can independently regulate both Pol I- and Pol III-mediated transcription and act as a key coordinator of Pol I and Pol III.


Asunto(s)
Neoplasias , Factores Asociados con la Proteína de Unión a TATA , Humanos , ADN Ribosómico/genética , Neoplasias/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , ARN Polimerasa I/genética , ARN Polimerasa I/metabolismo , ARN Polimerasa III/genética , ARN Polimerasa III/metabolismo , Factores Asociados con la Proteína de Unión a TATA/genética , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Proteína de Unión a TATA-Box/genética , Proteína de Unión a TATA-Box/metabolismo , Factor de Transcripción TFIIB/genética , Factor de Transcripción TFIIB/metabolismo , Factores de Transcripción/genética , Transcripción Genética
2.
Nat Methods ; 19(3): 359-369, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35277709

RESUMEN

Long-term visualization of the dynamic interactions between intracellular structures throughout the three-dimensional space of whole live cells is essential to better understand their functions, but this task remains challenging due to the limitations of existing three-dimensional fluorescence microscopy techniques, such as an insufficient axial resolution, low volumetric imaging rate and photobleaching. Here, we present the combination of a progressive deep-learning super-resolution strategy with a double-ring-modulated selective plane illumination microscopy design capable of visualizing the dynamics of intracellular structures in live cells for hours at an isotropic spatial resolution of roughly 100 nm in three dimensions at speeds up to roughly 17 Hz. Using this approach, we reveal the complex spatial relationships and interactions between endoplasmic reticulum (ER) and mitochondria throughout live cells, providing new insights into ER-mediated mitochondrial division. We also examined the motion of Drp1 oligomers involved in mitochondrial fission and revealed the dynamic interactions between Drp1 and mitochondria in three dimensions.


Asunto(s)
Retículo Endoplásmico , Mitocondrias , Retículo Endoplásmico/metabolismo , Imagenología Tridimensional/métodos , Microscopía Fluorescente/métodos , Fotoblanqueo
3.
J Cell Mol Med ; 28(7): e18215, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38509755

RESUMEN

Oligoasthenoteratospermia (OAT), characterized by abnormally low sperm count, poor sperm motility, and abnormally high number of deformed spermatozoa, is an important cause of male infertility. Its genetic basis in many affected individuals remains unknown. Here, we found that CCDC157 variants are associated with OAT. In two cohorts, a 21-bp (g.30768132_30768152del21) and/or 24-bp (g.30772543_30772566del24) deletion of CCDC157 were identified in five sporadic OAT patients, and 2 cases within one pedigree. In a mouse model, loss of Ccdc157 led to male sterility with OAT-like phenotypes. Electron microscopy revealed misstructured acrosome and abnormal head-tail coupling apparatus in the sperm of Ccdc157-null mice. Comparative transcriptome analysis showed that the Ccdc157 mutation alters the expressions of genes involved in cell migration/motility and Golgi components. Abnormal Golgi apparatus and decreased expressions of genes involved in acrosome formation and lipid metabolism were detected in Ccdc157-deprived mouse germ cells. Interestingly, we attempted to treat infertile patients and Ccdc157 mutant mice with a Chinese medicine, Huangjin Zanyu, which improved the fertility in one patient and most mice that carried the heterozygous mutation in CCDC157. Healthy offspring were produced. Our study reveals CCDC157 is essential for sperm maturation and may serve as a marker for diagnosis of OAT.


Asunto(s)
Astenozoospermia , Infertilidad Masculina , Proteínas de la Membrana , Oligospermia , Animales , Humanos , Masculino , Ratones , Astenozoospermia/genética , Astenozoospermia/metabolismo , Infertilidad Masculina/genética , Infertilidad Masculina/metabolismo , Ratones Noqueados , Mutación/genética , Oligospermia/genética , Oligospermia/metabolismo , Semen/metabolismo , Motilidad Espermática/genética , Espermatozoides/metabolismo , Proteínas de la Membrana/metabolismo
4.
J Biol Chem ; 299(3): 102945, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36707053

RESUMEN

Deregulation of transcription factor AP2 alpha (TFAP2A) and RNA polymerase III (Pol III) products is associated with tumorigenesis. However, the mechanism underlying this event is not fully understood and the connection between TFAP2A and Pol III-directed transcription has not been investigated. Here, we report that TFAP2A functions as a positive factor in the regulation of Pol III-directed transcription and cell proliferation. We found TFAP2A is also required for the activation of Pol III transcription induced by the silencing of filamin A, a well-known cytoskeletal protein and an inhibitor in Pol III-dependent transcription identified previously. Using a chromatin immunoprecipitation technique, we showed TFAP2A positively modulates the assembly of Pol III transcription machinery factors at Pol III-transcribed gene loci. We found TFAP2A can activate the expression of Pol III transcription-related factors, including BRF1, GTF3C2, and c-MYC. Furthermore, we demonstrate TFAP2A enhances expression of MDM2, a negative regulator of tumor suppressor p53, and also inhibits p53 expression. Finally, we found MDM2 overexpression can rescue the inhibition of Pol III-directed transcription and cell proliferation caused by TFAP2A silencing. In summary, we identified that TFAP2A can activate Pol III-directed transcription by controlling multiple pathways, including general transcription factors, c-MYC and MDM2/p53. The findings from this study provide novel insights into the regulatory mechanisms of Pol III-dependent transcription and cancer cell proliferation.


Asunto(s)
Neoplasias , Factores Asociados con la Proteína de Unión a TATA , Factor de Transcripción AP-2 , Humanos , Proliferación Celular , ARN Polimerasa III/metabolismo , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Factor de Transcripción AP-2/genética , Factor de Transcripción AP-2/metabolismo , Transcripción Genética , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo
5.
Brief Bioinform ; 23(1)2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-34875683

RESUMEN

MiRNAs are a class of small non-coding RNA molecules that play an important role in many biological processes, and determining miRNA-disease associations can benefit drug development and clinical diagnosis. Although great efforts have been made to develop miRNA-disease association prediction methods, few attention has been paid to in-depth classification of miRNA-disease associations, e.g. up/down-regulation of miRNAs in diseases. In this paper, we regard known miRNA-disease associations as a signed bipartite network, which has miRNA nodes, disease nodes and two types of edges representing up/down-regulation of miRNAs in diseases, and propose a signed graph neural network method (SGNNMD) for predicting deregulation types of miRNA-disease associations. SGNNMD extracts subgraphs around miRNA-disease pairs from the signed bipartite network and learns structural features of subgraphs via a labeling algorithm and a neural network, and then combines them with biological features (i.e. miRNA-miRNA functional similarity and disease-disease semantic similarity) to build the prediction model. In the computational experiments, SGNNMD achieves highly competitive performance when compared with several baselines, including the signed graph link prediction methods, multi-relation prediction methods and one existing deregulation type prediction method. Moreover, SGNNMD has good inductive capability and can generalize to miRNAs/diseases unseen during the training.


Asunto(s)
MicroARNs , Redes Neurales de la Computación , Algoritmos , Biología Computacional/métodos , Regulación hacia Abajo , MicroARNs/genética
6.
Artículo en Inglés | MEDLINE | ID: mdl-38815737

RESUMEN

OBJECTIVE: Kashin-Beck disease (KBD) is an endemic, degenerative, and cartilage-damaging disease for which low selenium and T-2 toxins are considered environmental pathogenic factors. This study aimed to investigate the molecular mechanisms of autophagy in cartilage damage caused by T-2 toxin and the protective effect of chondroitin sulfate A nano-elemental selenium (CSA-SeNP) on the cartilage. METHODS: KBD chondrocytes and C28/I2 human chondrocyte cell lines were used. T-2 toxin, AKT inhibitor, and CSA-SeNP treatment experiments were conducted separately, with a treatment time of 24 h. Autophagy was monitored using MDC staining, and mRFP-GFP-LC3 adenovirus, respectively. RT-qPCR and western blotting were used to detect the expression of the relevant genes and proteins. RESULTS: The suppression of autophagy observed in KBD chondrocytes was replicated by applying 10 ng/mL T-2 toxin to C28/I2 chondrocytes for 24 h. The AKT/TSCR/Rheb/mTOR signaling pathway was activated by T-2 toxin, which inhibits autophagy. The supplementation with CSA-SeNP alleviated the inhibition of autophagy by T-2 toxin through the AKT/TSCR/Rheb/mTOR signaling pathway. CONCLUSIONS: Loss of autophagy regulated by the AKT/TSCR/Rheb/mTOR signaling pathway plays an important role in cartilage damage caused by T-2 toxin. CSA-SeNP supplementation attenuated inhibition of autophagy in chondrocytes by T-2 toxin by modulating this signaling pathway. These findings provide promising new targets for the prevention and treatment of cartilage disease.

7.
Opt Express ; 32(7): 12243-12256, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571053

RESUMEN

Integral imaging is a kind of true three-dimensional (3D) display technology that uses a lens array to reconstruct vivid 3D images with full parallax and true color. In order to present a high-quality 3D image, it's vital to correct the axial position error caused by the misalignment and deformation of the lens array which makes the reconstructed lights deviate from the correct directions, resulting in severe voxel drifting and image blurring. We proposed a sub-pixel marking method to measure the axial position error of the lenses with great accuracy by addressing the sub-pixels under each lens and forming a homologous sub-pixel pair. The proposed measurement method relies on the geometric center alignment of image points, which is specifically expressed as the overlap between the test 3D voxel and the reference 3D voxel. Hence, measurement accuracy could be higher. Additionally, a depth-based sub-pixel correction method was proposed to eliminate the voxel drifting. The proposed correction method takes the voxel depth into consideration in the correction coefficient, and achieves accurate error correction for 3D images with different depths. The experimental results well confirmed that the proposed measuring and correction methods can greatly suppress the voxel drifting caused by the axial position error of the lenses, and greatly improve the 3D image quality.

8.
Exp Cell Res ; 428(2): 113651, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37201744

RESUMEN

Oncoprotein-induced transcript 3 (OIT3) facilitates macrophage M2 polarization and hepatocellular carcinoma (HCC) progression, however, whether OIT3 regulates tumor immunity remains largely unknown. Here we found that OIT3 was upregulated in HCC-associated macrophages, which inhibited CD4+ and CD8+ T-cell infiltration in the tumor microenvironment (TME). Mechanistically, OIT3 increased the expression of PD-L1 on tumor-associated macrophages (TAMs) by activating NF-κB signaling, blockade of NF-κB reversed the immunosuppressive activity of TAMs and dampens HCC tumorigenesis. Our findings provide the molecular basis for OIT3 enhancing tumor immunosuppression and highlighted a potential therapeutic strategy for targeting the TAMs of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Antígeno B7-H1/metabolismo , Carcinogénesis/patología , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Neoplasias Hepáticas/metabolismo , Macrófagos/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Proteínas Oncogénicas/metabolismo , Microambiente Tumoral
9.
Arch Phys Med Rehabil ; 105(2): 235-242, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37392780

RESUMEN

OBJECTIVE: To identify clinical factors (physical and psychological symptoms and post-traumatic growth) that predict social participation outcome at 24-month after burn injury. DESIGN: A prospective cohort study based on Burn Model System National Database. SETTING: Burn Model System centers. PARTICIPANTS: 181 adult participants less than 2 years after burn injury (N=181). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Demographic and injury variables were collected at discharge. Predictor variables were assessed at 6 and 12 months: Post-Traumatic Growth Inventory Short Form (PTGI-SF), Post-Traumatic Stress Disorder Checklist Civilian Version (PCL-C), Patient-Reported Outcomes Measurement Information System (PROMIS-29) Depression, Anxiety, Sleep Disturbance, Fatigue, and Pain Interference short forms, and self-reported Heat Intolerance. Social participation was measured at 24 months using the Life Impact Burn Recovery Evaluation (LIBRE) Social Interactions and Social Activities short forms. RESULTS: Linear and multivariable regression models were used to examine predictor variables for social participation outcomes, controlling for demographic and injury variables. For LIBRE Social Interactions, significant predictors included the PCL-C total score at 6 months (ß=-0.27, P<.001) and 12 months (ß=-0.39, P<.001), and PROMIS-29 Pain Interference at 6 months (ß=-0.20, P<.01). For LIBRE Social Activities, significant predictors consisted of the PROMIS-29 Depression at 6 months (ß=-0.37, P<.001) and 12 months (ß=-0.37, P<.001), PROMIS-29 Pain Interference at 6 months (ß=-0.40, P<.001) and 12 months (ß=-0.37, P<.001), and Heat Intolerance at 12 months (ß=-4.55, P<.01). CONCLUSIONS: Post-traumatic stress and pain predicted social interactions outcomes, while depression, pain and heat intolerance predicted social activities outcomes in people with burn injury.


Asunto(s)
Quemaduras , Participación Social , Adulto , Humanos , Estudios Prospectivos , Calidad de Vida/psicología , Dolor , Quemaduras/psicología
10.
Artículo en Inglés | MEDLINE | ID: mdl-38754720

RESUMEN

OBJECTIVE: To examine the moderation effects of daily behavior on the associations between symptoms and social participation outcomes after burn injury. DESIGN: A 6-month prospective cohort study. SETTING: Community. PARTICIPANTS: Twenty-four adult burn survivors. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Symptoms and social participation outcomes were assessed weekly using smartphone surveys, including symptoms of pain (Patient-Reported Outcomes Measurement Information System [PROMIS] Pain Intensity and Pain Interference), anxiety (PROMIS Anxiety), and depression (Patient Health Questionnaire), as well as outcomes of social interactions and social activities (Life Impact Burn Recovery Evaluation [LIBRE] Social Interactions and Social Activities). Daily behaviors were automatically recorded by a smartphone application and smartphone logs, including physical activity (steps, travel miles, and activity minutes), sleep (sleep hours), and social contact (number of phone calls and message contacts). RESULTS: Multilevel models controlling for demographic and burn injury variables examined the associations between symptoms and social participation outcomes and the moderation effects of daily behaviors. Lower (worse) LIBRE Social Interactions and LIBRE Social Activities scores were significantly associated with higher (worse) PROMIS Pain Intensity, PROMIS Pain Interference, PROMIS Anxiety, and Patient Health Questionnaire-8 scores (P<.05). Additionally, daily steps and activity minutes were associated with LIBRE Social Interactions and LIBRE Social Activities (P<.05), and significantly moderated the association between PROMIS Anxiety and LIBRE Social Activities (P<.001). CONCLUSIONS: Social participation outcomes are associated with pain, anxiety, and depression symptoms after burn injury, and are buffered by daily physical activity. Future intervention studies should examine physical activity promotion to improve social recovery after burns.

11.
Ecotoxicol Environ Saf ; 279: 116503, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38810288

RESUMEN

Kashin-Beck disease (KBD) is an endemic, environmentally associated cartilage disease. Previous studies have shown that the environmental suspected pathogenic factors of KBD, T-2 toxin and low selenium, are involved in the regulation of inflammation, oxidative stress and autophagy in some tissues and organs. In cartilage diseases, the level of cellular autophagy determines the fate of the chondrocytes. However, whether autophagy is involved in KBD cartilage lesions, and the role of low selenium and T-2 toxins in KBD cartilage injury and autophagy are still unclear. This work took the classical AMPK/mTOR/ULK1 autophagy regulatory pathway as the entry point to clarify the relationship between the environmental suspected pathogenic factors and chondrocyte autophagy. Transmission electron microscopy was used to observe the autophagy of chondrocytes in KBD patients. qRT-PCR and western blot were used to analyze the expression of AMPK/mTOR/ULK1 pathway and autophagy markers. The rat model of KBD was established by low selenium and T-2 toxin, the autophagy in rat cartilage was detected after 4- and 12-week interventions. Chondrocyte autophagy was found in KBD, and the AMPK/mTOR/ULK1 pathway was down-regulated. In the rat model, the pathway showed an up-regulated trend when low selenium and T-2 toxin, were treated for a short time or low concentration, and autophagy level increased. However, when low selenium and T-2 toxin were treated for a long time or at high concentrations, the pathway showed a down-regulated trend, and the autophagy level was reduced and even defective. In conclusion, in the process of KBD cartilage lesion, chondrocyte autophagy level may increase in the early stage, and decrease in the late stage with the progression of lesion. Low selenium and T-2 toxins may affect autophagy by AMPK/mTOR/ULK1 pathway.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Condrocitos , Enfermedad de Kashin-Beck , Selenio , Toxina T-2 , Serina-Treonina Quinasas TOR , Toxina T-2/toxicidad , Toxina T-2/análogos & derivados , Autofagia/efectos de los fármacos , Enfermedad de Kashin-Beck/patología , Serina-Treonina Quinasas TOR/metabolismo , Animales , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Masculino , Condrocitos/efectos de los fármacos , Condrocitos/patología , Humanos , Proteínas Quinasas Activadas por AMP/metabolismo , Ratas , Femenino , Persona de Mediana Edad , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Adulto , Péptidos y Proteínas de Señalización Intracelular
12.
Molecules ; 29(5)2024 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-38474642

RESUMEN

Biochar (BC) is a new type of carbon material with a high specific surface area, porous structure, and good adsorption capacity, which can effectively adsorb and enrich organic pollutants. Meanwhile, nano zero-valent iron (nZVI) has excellent catalytic activity and can rapidly degrade organic pollutants through reduction and oxidation reactions. The combined utilization of BC and nZVI can not only give full play to their advantages in the adsorption and catalytic degradation of organic pollutants, but also help to reduce the agglomeration of nZVI, thus improving its efficiency in water treatment and providing strong technical support for water resources protection and environmental quality improvement. This article provides a detailed introduction to the preparation method and characterization technology, reaction mechanism, influencing factors, and specific applications of BC and nZVI, and elaborates on the research progress of BC-nZVI in activating persulfate (PS) to degrade organic pollutants in water. It has been proven experimentally that BC-nZVI can effectively remove phenols, dyes, pesticides, and other organic pollutants. Meanwhile, in response to the existing problems in current research, this article proposes future research directions and challenges, and summarizes the application prospects and development trends of BC-nZVI in water treatment. In summary, BC-nZVI-activated PS is an efficient technology for degrading organic pollutants in water, providing an effective solution for protecting water resources and improving environmental quality, and has significant application value.

13.
Molecules ; 29(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38474682

RESUMEN

Nowadays, antibiotics are widely used, increasing the risk of contamination of the water body and further threatening human health. The traditional water treatment process is less efficient in degrading antibiotics, and the advanced oxidation process (AOPs) is cleaner and more efficient than the traditional biochemical degradation process. The combined ozone/peroxymonosulfate (PMS) advanced oxidation process (O3/PMS) based on sulfate radical (SO4•-) and hydroxyl radical (•OH) has developed rapidly in recent years. The O3/PMS process has become one of the most effective ways to treat antibiotic wastewater. The reaction mechanism of O3/PMS was reviewed in this paper, and the research and application progress of the O3/PMS process in the degradation of antibiotics in drinking water and wastewater effluent were evaluated. The operation characteristics and current application range of the process were summarized, which has a certain reference value for further research on O3/PMS process.


Asunto(s)
Agua Potable , Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Humanos , Aguas Residuales , Antibacterianos , Contaminantes Químicos del Agua/análisis , Peróxidos , Oxidación-Reducción
14.
J Biol Chem ; 298(3): 101581, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35038452

RESUMEN

RNA polymerase III (pol III) products play fundamental roles in a variety of cellular processes, including protein synthesis and cancer cell proliferation. In addition, dysregulation of pol III-directed transcription closely correlates with tumorigenesis. It is therefore of interest to identify novel pathways or factors governing pol III-directed transcription. Here, we show that transcription factor (TF) GATA binding protein 4 (GATA4) expression in SaOS2 cells was stimulated by the silencing of filamin A (FLNA), a repressor of pol III-directed transcription, suggesting that GATA4 is potentially associated with the regulation of pol III-directed transcription. Indeed, we show that GATA4 expression positively correlates with pol III-mediated transcription and tumor cell proliferation. Mechanistically, we found that GATA4 depletion inhibits the occupancies of the pol III transcription machinery factors at the loci of pol III target genes by reducing expression of both TFIIIB subunit TFIIB-related factor 1 and TFIIIC subunit general transcription factor 3C subunit 2 (GTF3C2). GATA4 has been shown to activate specificity factor 1 (Sp1) gene transcription by binding to the Sp1 gene promoter, and Sp1 has been confirmed to activate pol III gene transcription by directly binding to both Brf1 and Gtf3c2 gene promoters. Thus, the findings from this study suggest that GATA4 links FLNA and Sp1 signaling to form an FLNA/GATA4/Sp1 axis to modulate pol III-directed transcription and transformed cell proliferation. Taken together, these results provide novel insights into the regulatory mechanism of pol III-directed transcription.


Asunto(s)
Filaminas , Factor de Transcripción GATA4 , Proteínas Quinasas , ARN Polimerasa III , Proliferación Celular , Filaminas/genética , Filaminas/metabolismo , Factor de Transcripción GATA4/genética , Factor de Transcripción GATA4/metabolismo , Proteínas Quinasas/metabolismo , ARN Polimerasa III/metabolismo , Transducción de Señal , Factores de Transcripción/genética , Transcripción Genética
15.
Br J Cancer ; 128(5): 766-782, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36526675

RESUMEN

BACKGROUND: Deregulation of either RNA polymerase I (Pol I)-directed transcription or expression of signal transducer and activator of transcription 3 (STAT3) correlates closely with tumorigenesis. However, the connection between STAT3 and Pol I-directed transcription hasn't been investigated. METHODS: The role of STAT3 in Pol I-directed transcription was determined using combined techniques. The regulation of tumor cell growth mediated by STAT3 and Pol I products was analyzed in vitro and in vivo. RNAseq, ChIP assays and rescue assays were used to uncover the mechanism of Pol I transcription mediated by STAT3. RESULTS: STAT3 expression positively correlates with Pol I product levels and cancer cell growth. The inhibition of STAT3 or Pol I products suppresses cell growth. Mechanistically, STAT3 activates Pol I-directed transcription by enhancing the recruitment of the Pol I transcription machinery to the rDNA promoter. STAT3 directly activates Rpa34 gene transcription by binding to the RPA34 promoter, which enhances the occupancies of the Pol II transcription machinery factors at this promoter. Cancer patients with RPA34 high expression lead to poor survival probability and short survival time. CONCLUSION: STAT3 potentiates Pol I-dependent transcription and tumor cell growth by activating RPA34 in vitro and in vivo.


Asunto(s)
ARN Polimerasa I , Factor de Transcripción STAT3 , Transcripción Genética , Humanos , Regiones Promotoras Genéticas , ARN Polimerasa I/genética , ARN Polimerasa II/genética , ARN Polimerasa II/metabolismo , Factor de Transcripción STAT3/metabolismo
16.
Radiology ; 307(1): e220739, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36413130

RESUMEN

Background Liver microcirculation dysfunction plays a vital role in the occurrence and development of liver diseases, and thus, there is a clinical need for in vivo, noninvasive, and quantitative evaluation of liver microcirculation. Purpose To evaluate the feasibility of ultrasensitive US microvessel imaging (UMI) in the visualization and quantification of hepatic microvessels in healthy and cirrhotic rats. Materials and Methods In vivo studies were performed to image hepatic microvasculature by means of laparotomy in Sprague-Dawley rats (five cirrhotic and five control rats). In vivo conventional power Doppler US and ex vivo micro-CT were performed for comparison. UMI-based quantifications of perfusion, tortuosity, and integrity of microvessels were compared between the control and cirrhotic groups by using the Wilcoxon test. Spearman correlations between quantification parameters and pathologic fibrosis, perfusion function, and hepatic hypoxia were evaluated. Results UMI helped detect minute vessels below the liver capsule, as compared with conventional power Doppler US and micro-CT. With use of UMI, lower perfusion indicated by vessel density (median, 22% [IQR, 20%-28%] vs 41% [IQR, 37%-46%]; P = .008) and fractional moving blood volume (FMBV) (median, 6.4% [IQR, 4.8%-8.6%] vs 13% [IQR, 12%-14%]; P = .008) and higher tortuosity indicated by the sum of angles metric (SOAM) (median, 3.0 [IQR, 2.9-3.0] vs 2.7 [IQR, 2.6-2.9]; P = .008) were demonstrated in the cirrhotic rat group compared with the control group. Vessel density (r = 0.85, P = .003), FMBV (r = 0.86, P = .002), and median SOAM (r = -0.83, P = .003) showed strong correlations with pathologically derived vessel density labeled with dextran. Vessel density (r = -0.81, P = .005) and median SOAM (r = 0.87, P = .001) also showed strong correlations with hepatic tissue hypoxia. Conclusion Contrast-free ultrasensitive US microvessel imaging provided noninvasive in vivo imaging and quantification of hepatic microvessels in cirrhotic rat liver. © RSNA, 2022 Supplemental material is available for this article. See also the editorial by Fetzer in this issue.


Asunto(s)
Hígado , Microvasos , Ratas , Animales , Microcirculación , Ratas Sprague-Dawley , Hígado/patología , Microvasos/diagnóstico por imagen , Microvasos/patología , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/patología
17.
BMC Med ; 21(1): 77, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36855099

RESUMEN

BACKGROUND: Heterozygous familial hypercholesterolemia (HeFH) is largely underdiagnosed and undertreated in China where few patients achieved recommended target levels of low density lipoprotein cholesterol (LDL-C). We conducted the first randomized, placebo-controlled clinical trial in Chinese patients with HeFH to assess the efficacy and safety of tafolecimab, a novel fully human proprotein convertase subtilisin/kexin type 9 (PCSK9) monoclonal antibody. METHODS: Patients diagnosed with HeFH by Simon Broome criteria and on a stable lipid-lowering therapy for at least 4 weeks were randomized 2:2:1:1 to receive subcutaneous tafolecimab 150 mg every 2 weeks (Q2W), tafolecimab 450 mg every 4 weeks (Q4W), placebo Q2W or placebo Q4W in the 12-week double-blind treatment period. After that, participants received open-label tafolecimab 150 mg Q2W or 450 mg Q4W for 12 weeks. The primary endpoint was the percent change from baseline to week 12 in LDL-C levels. Secondary endpoints included proportion of participants achieving ≥50% LDL-C reductions and proportion of participants with LDL-C <1.8 mmol/L at week 12 and 24, the change from baseline to week 12 in non-high density lipoprotein cholesterol (non-HDL-C), apolipoprotein B and lipoprotein(a) levels, as well as the change from baseline to week 24 in lipid levels. RESULTS: In total, 149 participants were randomized and 148 received at least one dose of the study treatment. At week 12, tafolecimab treatment induced significant reductions in LDL-C levels (treatment difference versus placebo [on-treatment estimand]: -57.4% [97.5% CI, -69.2 to -45.5] for 150 mg Q2W; -61.9% [-73.4 to -50.4] for 450 mg Q4W; both P <0.0001). At both dose regimens, significantly more participants treated with tafolecimab achieved ≥50% LDL-C reductions or LDL-C <1.8 mmol/L at week 12 as compared with corresponding placebo groups (all P <0.0001). Meanwhile, non-HDL-C, apolipoprotein B and lipoprotein(a) levels were significantly reduced in the tafolecimab groups at week 12. The lipid-lowering effects of tafolecimab were maintained till week 24. During the double-blind treatment period, the most commonly-reported adverse events in the tafolecimab groups included upper respiratory tract infection, increased blood creatine phosphokinase, increased alanine aminotransferase, increased aspartate aminotransferase and hypertension. CONCLUSIONS: Tafolecimab administered either 150 mg Q2W or 450 mg Q4W yielded significant and persistent reductions in LDL-C levels and showed a favorable safety profile in Chinese patients with HeFH. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04179669.


Asunto(s)
Anticuerpos Monoclonales , Hipercolesterolemia , Hiperlipoproteinemia Tipo II , Inhibidores de PCSK9 , Humanos , Anticuerpos Monoclonales/uso terapéutico , Apolipoproteínas , LDL-Colesterol , Pueblos del Este de Asia , Hiperlipoproteinemia Tipo II/tratamiento farmacológico , Lipoproteína(a) , Inhibidores de PCSK9/uso terapéutico
18.
Opt Express ; 31(18): 29132-29144, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37710719

RESUMEN

Compared with conventional scattered backlight systems, integral imaging (InIm) display system with collimated backlight can reduce the voxel size, but apparent voxel separation and severe graininess still exist in reconstructed 3D images. In this paper, an InIm 3D display system with anisotropic backlight control of sub-pixels was proposed to resolve both voxel aliasing and voxel separation simultaneously. It consists of an anisotropic backlight unit (ABU), a transmissive liquid crystal panel (LCP), and a lens array. The ABU with specific horizontal and vertical divergence angles was proposed and designed. Within the depth of field, the light rays emitted from sub-pixels are controlled precisely by the ABU to minimize the voxel size as well as stitch adjacent voxels seamlessly, thus improving the 3D image quality effectively. In the experiment, the prototype of our proposed ABU-type InIm system was developed, and the spatial frequency was nearly two times of conventional scattered backlight InIm system. Additionally, the proposed system eliminated the voxel separation which usually occurs in collimated backlight InIm system. As a result, voxels reconstructed by our proposed system were stitched in space without aliasing and separation, thereby greatly enhancing the 3D resolution and image quality.

19.
BMC Cancer ; 23(1): 1076, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37936091

RESUMEN

BACKGROUND: The clinical profiles of recurrent retroperitoneal liposarcoma (RLS) need to be explored. The recurrence patterns of RLS are controversial and ambiguous. METHODS: A total of 138 patients with recurrent RLS were finally recruited in the study. The analysis of overall survival (OS) and recurrence-free survival (RFS) was performed by Kaplan‒Meier analysis. To identify independent prognostic factors, all significant variables on univariate Cox regression analysis (P ≤ 0.05) were subjected to multivariate Cox regression analysis. The corresponding nomogram model was further built to predict the survival status of patients. RESULTS: Among patients, the 1-, 3-, and 5-year OS rates were 70.7%, 35.9% and 30.9%, respectively. The 1-, 3- and 5-year RFS rates of the 55 patients who underwent R0 resection were 76.1%, 50.8% and 34.4%, respectively. The multivariate analysis revealed that resection method, tumor size, status of pathological differentiation, pathological subtypes and recurrence pattern were independent risk factors for OS or RFS. Patients with distant recurrence (DR) pattern usually had multifocal tumors (90.5% vs. 74.7%, P < 0.05); they were prone to experience changes of pathological differentiation (69.9% vs. 33.3%, P < 0.05) and had a better prognosis than those with local recurrence (LR) pattern. R0 resection and combined organ resection favored the survival of patients with DR pattern in some cases. CONCLUSIONS: Patients with DR pattern had better prognosis, and they may benefit more from aggressive combined resection than those with LR pattern. Classifying the recurrence patterns of RLS provides guidance for individualized clinical management of recurrent RLS.


Asunto(s)
Liposarcoma , Neoplasias Retroperitoneales , Humanos , Recurrencia Local de Neoplasia/patología , Liposarcoma/patología , Neoplasias Retroperitoneales/cirugía , Neoplasias Retroperitoneales/patología , Espacio Retroperitoneal/patología , Pronóstico , Tasa de Supervivencia , Estudios Retrospectivos
20.
Crit Rev Food Sci Nutr ; 63(9): 1155-1169, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36394558

RESUMEN

Barley is one of the world's oldest cereal crops forming an important component of many traditional diets. Barley is rich in a variety of bioactive phytochemicals with potentially health-promoting effects. However, its beneficial nutritional attributes are not being fully realized because of the limited number of foods it is currently utilized in. It is therefore crucial for the food industry to produce novel barley-based foods that are healthy and cater to customers' tastes. This article reviews the nutritional and functional characteristics of barley, with an emphasis on its ability to improve glucose/lipid metabolism. Then, recent trends in barley product development are discussed. Finally, current limitations and future research directions in glucolipid modulation mechanisms and barley bioprocessing are discussed.


Asunto(s)
Hordeum , Hordeum/química , Suplementos Dietéticos , Nutrientes , Dieta , Grano Comestible
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