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1.
bioRxiv ; 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38586061

RESUMEN

During B cell development, cells progress through multiple developmental stages with the pro-B cell stage defining commitment to the B cell lineage. YY1 is a ubiquitous transcription factor that is capable of both activation and repression functions. We find here that knockout of YY1 at the pro-B cell stage eliminates B lineage commitment. YY1 knockout pro-B cells can generate T lineage cells in vitro using the OP9- DL4 feeder system, as well as in vivo after injection into sub-lethally irradiated Rag1 -/- mice. These T lineage-like cells lose their B lineage transcript profile and gain a T cell lineage profile. Single cell-RNA-seq experiments showed that as YY1 knockout pro-B cells transition into T lineage cells, various cell clusters adopt transcript profiles representing a multiplicity of hematopoietic lineages indicating unusual lineage plasticity. Given the ubiquitous nature of YY1 and its dual activation and repression functions, YY1 likely regulates commitment in multiple cell lineages.

2.
Microbiol Spectr ; 12(3): e0375022, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38299851

RESUMEN

Chronic wasting disease (CWD) is a naturally occurring prion disease in cervids that has been rapidly proliferating in the United States. Here, we investigated a potential link between CWD infection and gut microbiome by analyzing 50 fecal samples obtained from CWD-positive animals of different sexes from various regions in the USA compared to 50 CWD-negative controls using high throughput sequencing of the 16S ribosomal RNA and targeted metabolomics. Our analysis reveals promising trends in the gut microbiota that could potentially be CWD-dependent, including several bacterial taxa at each rank level, as well as taxa pairs, that can differentiate between CWD-negative and CWD-positive deer. Through machine-learning, these taxa and taxa pairs at each rank level could facilitate identification of around 70% of both the CWD-negative and the CWD-positive samples. Our results provide a potential tool for diagnostics and surveillance of CWD in the wild, as well as conceptual advances in our understanding of the disease.IMPORTANCEThis is a comprehensive study that tests the connection between the composition of the gut microbiome in deer in response to chronic wasting disease (CWD). We analyzed 50 fecal samples obtained from CWD-positive animals compared to 50 CWD-negative controls to identify CWD-dependent changes in the gut microbiome, matched with the analysis of fecal metabolites. Our results show promising trends suggesting that fecal microbial composition can directly correspond to CWD disease status. These results point to the microbial composition of the feces as a potential tool for diagnostics and surveillance of CWD in the wild, including non-invasive CWD detection in asymptomatic deer and deer habitats, and enable conceptual advances in our understanding of the disease.


Asunto(s)
Ciervos , Enfermedad Debilitante Crónica , Animales , Enfermedad Debilitante Crónica/diagnóstico , Enfermedad Debilitante Crónica/genética , Enfermedad Debilitante Crónica/metabolismo , Estudios Prospectivos , Heces , Biomarcadores/metabolismo
3.
ISA Trans ; 147: 403-438, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38320916

RESUMEN

Diagnosis of incipient faults of metro train bearings is a difficult problem under the double masking of strong wheel-rail impact interference and background noise. A novel feature extraction method using improved complementary complete local mean decomposition with adaptive noise (ICCELMDAN) and mixture correntropy-based adaptive feature enhancement (AFE) is proposed in this paper. The ICCELMDAN method uses a proposed complementary adaptive noise-assisted iterative sifting method to improve its anti-mixing and anti-splitting performance, and then can extract the complete feature from faulty bearing signals under strong background noise. The AFE method adaptively obtains the optimal parameters of mixture correntropy (MC) by employing a newly developed fault energy of mixture correntropy as the objective function in the marine predators algorithm (MPA), and can enhance the weak fault characteristic signal under strong wheel-rail impact interferences. The proposed method effectively combines the complete feature extraction capability of ICCELMDAN and the powerful feature enhancement capability of AFE, which can accurately diagnose the weak faults of metro train bearings under strong wheel-rail impact interferences in simulated and practical scenarios. Furthermore, it outperforms the existing methods in completeness of feature extraction, diagnosis accuracy and robustness from the comparative studies.

4.
Diabetol Metab Syndr ; 16(1): 32, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297321

RESUMEN

BACKGROUND AND PURPOSE: Glucose-to-glycated hemoglobin ratio (GAR) is considered a more reliable marker of stress hyperglycemia by correcting for basal blood glucose levels. This study aimed to investigate the extent to which GAR is associated with 3 month and 1 year all-cause mortalities in patients with acute ischemic stroke (AIS) undergoing mechanical thrombectomy (MT). METHODS: We retrospectively followed 553 AIS patients who underwent MT. The degree of stress hyperglycemia was quantified as the GAR, defined as fasting plasma glucose (mmol/L)/hemoglobin A1c (HbA1c) (%) on the second day after admission. According to the GAR quartiles, the patients were further categorized into four groups (group 1-group 4). We assessed the association between GAR and all-cause mortalities, clinical outcomes during hospitalization and function outcomes at 3 months. The associations between stress hyperglycemia and all-cause mortalities were analyzed using a Cox proportional-hazards model, while other outcomes were analyzed using multiple logistic regression analysis. RESULTS: The follow-up lasted a median of 18 months (range 0-66 months). The 3 month mortality rate was 9.58% (n = 53) and the 1 year mortality rate was 18.62% (n = 103). The Kaplan-Meier analysis revealed a significant inverse relationship between GAR and mortality (P < 0.001). In the Cox proportional-hazards model at 3 months, compared with group1, group 4 of GAR was associated with a significant increase in the risk of 3 month mortality (hazard ratio [HR] = 4.11, 95% confidence interval [CI] 1.41-12.0, P = 0.01) after adjusting for potential covariates. On multivariate logistic regression analysis, GAR was strongly associated with an increased risk of 3 month poor function outcome. CONCLUSIONS: Stress hyperglycemia, quantified by a higher GAR, is associated with all-cause mortality and poor functional outcomes in patients with AIS who undergo MT. Furthermore, GAR may contribute to improving the predictive efficiency of all-cause mortality in patients with AIS after MT, especially short-term all-cause mortality.

5.
Neural Regen Res ; 19(5): 1156-1160, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37862222

RESUMEN

Microvasculature of the retina is considered an alternative marker of cerebral vascular risk in healthy populations. However, the ability of retinal vasculature changes, specifically focusing on retinal vessel diameter, to predict the recurrence of cerebrovascular events in patients with ischemic stroke has not been determined comprehensively. While previous studies have shown a link between retinal vessel diameter and recurrent cerebrovascular events, they have not incorporated this information into a predictive model. Therefore, this study aimed to investigate the relationship between retinal vessel diameter and subsequent cerebrovascular events in patients with acute ischemic stroke. Additionally, we sought to establish a predictive model by combining retinal veessel diameter with traditional risk factors. We performed a prospective observational study of 141 patients with acute ischemic stroke who were admitted to the First Affiliated Hospital of Jinan University. All of these patients underwent digital retinal imaging within 72 hours of admission and were followed up for 3 years. We found that, after adjusting for related risk factors, patients with acute ischemic stroke with mean arteriolar diameter within 0.5-1.0 disc diameters of the disc margin (MAD0.5-1.0DD) of ≥ 74.14 µm and mean venular diameter within 0.5-1.0 disc diameters of the disc margin (MVD0.5-1.0DD) of ≥ 83.91 µm tended to experience recurrent cerebrovascular events. We established three multivariate Cox proportional hazard regression models: model 1 included traditional risk factors, model 2 added MAD0.5-1.0DD to model 1, and model 3 added MVD0.5-1.0DD to model 1. Model 3 had the greatest potential to predict subsequent cerebrovascular events, followed by model 2, and finally model 1. These findings indicate that combining retinal venular or arteriolar diameter with traditional risk factors could improve the prediction of recurrent cerebrovascular events in patients with acute ischemic stroke, and that retinal imaging could be a useful and non-invasive method for identifying high-risk patients who require closer monitoring and more aggressive management.

6.
Future Oncol ; 19(36): 2405-2416, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38018520

RESUMEN

Background: This single-center retrospective study compared the efficacy of breast-conserving therapy along with axillary lymph node dissection (ALND) with mastectomy and ALND with regard to survival of Chinese patients with occult breast cancer. Materials & methods: Univariate Kaplan-Meier analysis and multivariate Cox proportional hazards model were used to compare treatments and prognosis. Results: A total of 111 patients with a median follow-up of 72.9 months were included. 39 patients with mastectomy + ALND had better disease-free survival than 72 patients with breast-conserving therapy + ALND (HR = 0.31; p = 0.012). Patients with radiotherapy demonstrated inferior survival for both overall survival (HR = 2.67; p = 0.071) and disease-free survival (HR = 5.35; p = 0.002). Surgical strategies and radiotherapy remained significantly predictive of better disease-free survival in multivariate analyses. Conclusion: Mastectomy and ALND demonstrate superior disease-free prognosis compared with breast-conserving therapy and ALND in occult breast cancer.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/cirugía , Mastectomía , Estudios Retrospectivos , Pronóstico , Mastectomía Segmentaria , Escisión del Ganglio Linfático/efectos adversos , Biopsia del Ganglio Linfático Centinela
7.
bioRxiv ; 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37034790

RESUMEN

Lack of non-muscle ß -actin gene (Actb) leads to early embryonic lethality in mice, however mice with ß - to γ -actin replacement develop normally and show no detectable phenotypes at young age. Here we investigated the effect of this replacement in the retina. During aging, these mice have accelerated de-generation of retinal structure and function, including elongated microvilli and defective mitochondria of retinal pigment epithelium (RPE), abnormally bulging photoreceptor outer segments (OS) accompanied by reduced transducin concentration and light sensitivity, and accumulation of autofluorescent microglia cells in the subretinal space between RPE and OS. These defects are accompanied by changes in the F-actin binding of several key actin interacting partners, including ezrin, myosin, talin, and vinculin known to play central roles in modulating actin cytoskeleton and cell adhesion and mediating the phagocytosis of OS. Our data show that ß -actin protein is essential for maintaining normal retinal structure and function.

8.
J Mol Neurosci ; 72(12): 2389-2397, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36441377

RESUMEN

Focal cortical infarction leads to secondary degeneration of the ipsilateral hippocampus, which is associated with poststroke cognitive impairment. VX-765 is a potent small-molecule caspase-1 inhibitor that protects against central nervous system diseases. The present study aimed to determine the protective effects of VX-765 on ß-amyloid (Aß) deposition and secondary degeneration in the hippocampus as well as cognitive decline after cortical infarction. Sprague-Dawley rats were used to establish a distal middle cerebral artery occlusion (dMCAO) model and randomly divided into the vehicle and VX-765 groups. Rats in the vehicle and VX-765 groups, respectively, were subcutaneously injected with VX-765 (50 mg/kg/d) and an isopycnic vehicle once a day for 28 days, starting 1 h after dMCAO. At the end of this 28-day period, cognitive impairment was evaluated with the Morris water maze, and secondary hippocampal damage was evaluated with Nissl staining and immunostaining methods. Neuronal damage and pyroptosis were detected by TUNEL and immunoblotting. The results revealed that VX-765 treatment ameliorated poststroke cognitive dysfunction after ischemia. VX-765 reduced Aß deposition, neuronal loss, and glial activation compared with the vehicle control. In addition, VX-765 treatment increased BDNF levels and normalized synaptophysin protein levels in the hippocampus after cortical infarction. Notably, VX-765 treatment significantly reduced the expression of the pyroptosis-related molecules caspase-1, NLRP3, apoptosis-associated speck-like protein (ASC), gasdermin D, IL-1ß, and IL-18. Additionally, VX-765 significantly decreased the numbers of TUNEL-positive cells and the levels of Bax and cleaved caspase-3 (cC3) and enhanced the levels of Bcl-2 and Bcl-xl after ischemia. Inflammatory pathways, such as the NF-κB and mitogen-activated protein kinase (MAPK) pathways, were inhibited by VX-765 treatment after ischemia. These findings revealed that VX-765 reduced Aß deposition, pyroptosis, and apoptosis in the ipsilateral hippocampus, which may be associated with reduced secondary degeneration and cognitive decline following focal cortical infarction.


Asunto(s)
Disfunción Cognitiva , Hipocampo , Animales , Ratas , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/etiología , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Ratas Sprague-Dawley
9.
J Infect Dev Ctries ; 16(11): 1706-1714, 2022 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-36449642

RESUMEN

INTRODUCTION: Our study aimed to investigate the performance of deep learning (DL)-based diagnostic systems in alerting against COVID-19, especially among asymptomatic individuals coming from overseas, and to analyze the features of identified asymptomatic patients in detail. METHODOLOGY: DL diagnostic systems were deployed to assist in the screening of COVID-19, including the pneumonia system and pulmonary nodules system. 1,917 overseas returnees who underwent CT examination and rRT-PCR tests were enrolled. DL pneumonia system promptly alerted clinicians to suspected COVID-19 after CT examinations while the performance was evaluated with rRT-PCR results as the reference. The radiological features of asymptomatic COVID-19 cases were described according to the Nomenclature of the Fleischner Society. RESULTS: Fifty-three cases were confirmed as COVID-19 patients by rRT-PCR tests, including 5 asymptomatic cases. DL pneumonia system correctly alerted 50 cases as suspected COVID-19 with a sensitivity of 0.9434 and specificity of 0.9592 (within 2 minutes per case); while the pulmonary nodules system alerted 2 of the 3 missed asymptomatic cases. Additionally, five asymptomatic patients presented different characteristics such as elevated creatine kinase level and prolonged prothrombin time, as well as atypical radiological features. CONCLUSIONS: DL diagnostic systems are promising complementary approaches for prompt screening of imported COVID-19 patients, even the imported asymptomatic cases. Unique clinical and radiological characteristics of asymptomatic cases might be of great value in screening as well. ADVANCES IN KNOWLEDGE: DL-based systems are practical, efficient, and reliable to assist radiologists in screening COVID-19 patients. Differential features of asymptomatic patients might be useful to clinicians in the frontline to differentiate asymptomatic cases.


Asunto(s)
COVID-19 , Aprendizaje Profundo , Humanos , COVID-19/diagnóstico , Investigación , Radiólogos
10.
iScience ; 25(10): 105186, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36248738

RESUMEN

Cytoplasmic beta- and gamma-actin are ubiquitously expressed in every eukaryotic cell. They are encoded by different genes, but their amino acid sequences differ only by four conservative substitutions at the N-termini, making it difficult to dissect their individual regulation. Here, we analyzed actin from cultured cells and tissues by mass spectrometry and found that beta, unlike gamma actin, undergoes sequential removal of N-terminal Asp residues, leading to truncated actin species found in both F- and G-actin preparations. This processing affects up to ∼3% of beta actin in different cell types. We used CRISPR/Cas-9 in cultured cells to delete two candidate enzymes capable of mediating this type of processing. This deletion abolishes most of the beta actin N-terminal processing and results in changes in F-actin levels, cell spreading, filopodia formation, and cell migration. Our results demonstrate previously unknown isoform-specific actin regulation that can potentially affect actin functions in cells.

11.
Sci Rep ; 12(1): 15014, 2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36056159

RESUMEN

Under the background of automobile intelligence, cockpit comfort is receiving increasing attention, and intelligent cockpit comfort evaluation is especially important. To study the intelligent cockpit comfort evaluation model, this paper divides the intelligent cockpit comfort influencing factors into four factors and influencing indices: acoustic environment, optical environment, thermal environment, and human-computer interaction environment. The subjective and objective evaluation methods are used to obtain the subjective weights and objective weights of each index by the analytic hierarchy process and the improved entropy weight method, respectively. On this basis, the weights are combined by using the game theory viewpoint to obtain a comprehensive evaluation model of the intelligent automobile cockpit comfort. Then, the cloud algorithm was used to generate the rank comprehensive cloud model of each index for comparison. The research results found that among the four main factors affecting the intelligent automobile cockpit comfort, human-computer interaction has the greatest impact on it, followed by the thermal environment, acoustic environment, and optical environment. The results of the study can be used in intelligent cockpit design to make intelligent cockpits provide better services for people.


Asunto(s)
Algoritmos , Automóviles , Entropía , Humanos , Inteligencia
12.
ACS Appl Mater Interfaces ; 14(33): 38132-38143, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35971597

RESUMEN

Anion exchange membrane fuel cells (AEMFCs), which operate on a variety of green fuels, can achieve high power without emitting greenhouse gases. However, the lack of high ionic conductivity and long-term durability of anion-exchange membranes (AEMs) as their key components is a major obstacle hindering the commercial application of AEMFCs. Here, a series of homogeneous semi-interpenetrating network (semi-IPN) AEMs formed by cross-linking a copolymer of styrene (St) and 4-vinylbenzyl chloride (VBC) with branched polyethylenimine (BPEI) were designed. The pure carbon copolymer skeleton without sulfone/ether bonds accompanied by the semi-IPN endows the AEMs with excellent chemical stability. Moreover, the cross-linking effect of flexible BPEI chains is supposed to promote the "strong-flexible" mechanical properties, while the presence of multiquaternary ammonium groups can boost the formation of microphase separation, thereby enhancing the ionic conductivity of these AEMs. Consequently, the optimized (S1V1)3Q AEM exhibits an excellent hydroxide conductivity of 106 mS cm-1 at 80 °C, as well as more than 81% residual conductivity after soaking in 1 M NaOH at 60 °C for 720 h. Furthermore, the H2/O2 fuel cell assembled with (S1V1)3Q AEM delivers a peak power density of 150.2 mW cm-2 at 60 °C and 40% relative humidity. All results indicate that the approach of combining a pure carbon backbone polymer with a semi-IPN structure may be a viable strategy for fabricating AEMs that can be used in AEMFCs for long-term applications.

13.
Transl Neurodegener ; 11(1): 20, 2022 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-35395956

RESUMEN

BACKGROUND: Alpha-synuclein (α-syn) exhibits pathological misfolding in many human neurodegenerative disorders. We previously showed that α-syn is arginylated in the mouse brain and that lack of arginylation leads to neurodegeneration in mice. METHODS: Here, we tested α-syn arginylation in human brain pathology using newly derived antibodies in combination with Western blotting, biochemical assays, and experiments in live neurons. RESULTS: We found that α-syn was arginylated in the human brain on E46 and E83, two sites previously implicated in α-syn pathology and familial cases of Parkinson's disease. The levels of arginylation in different brain samples ranged between ~ 3% and ~ 50% of the total α-syn pool, and this arginylation nearly exclusively concentrated in the subcellular α-syn fraction that sedimented at low centrifugation speeds and appeared to be simultaneously targeted by multiple posttranslational modifications. Arginylated α-syn was less susceptible to S129 phosphorylation and pathological aggregation in neurons. The arginylation level inversely correlated with the overall α-syn levels and with patient age, suggesting a possible causal relationship between arginylation decline and α-syn-dependent neuropathology. CONCLUSION: We propose that α-syn arginylation constitutes a potential neuroprotective mechanism that prevents its abnormal accumulation during neurodegeneration and aging in the human brain.


Asunto(s)
Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Sinucleinopatías , Animales , Encéfalo/metabolismo , Humanos , Ratones , Enfermedad de Parkinson/patología , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
14.
Front Aging Neurosci ; 14: 1071377, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36688168

RESUMEN

Background and purpose: Stress hyperglycemia is common in critical and severe diseases. However, few studies have examined the association between stress hyperglycemia and the functional outcomes of patients with anterior circulation stroke, after mechanical thrombectomy (MT), in different diabetes status. This study therefore aimed to determine the relationship between stress hyperglycemia and the risk of adverse neurological functional outcomes in anterior circulation stroke patients with and without diabetes after MT. Methods: Data of 408 patients with acute anterior circulation stroke treated with MT through the green-channel treatment system for emergency stroke at the First Affiliated Hospital of Jinan University between January 2016 and December 2020 were reviewed retrospectively. The stress hyperglycemia ratio (SHR) was calculated as fasting plasma glucose (mmol/L) divided by glycosylated hemoglobin (%). The patients were stratified into four groups by quartiles of SHR (Q1-Q4). The primary outcome was an excellent (nondisabled) functional outcome at 3 months after admission (modified Rankin Scale score of 0-1). The relationship between stress hyperglycemia and neurological outcome after stroke was assessed using multivariate logistic regression. Results: After adjusting for potential confounders, compared with patients in Q1, those in Q4 were less likely to have an excellent outcome at 3 months (odds ratio [OR], 0.32, 95% confidence interval [CI], 0.14-0.66, p = 0.003), a good outcome at 3 months (OR, 0.41, 95% CI, 0.20-0.84, p = 0.020), and major neurological improvement (OR, 0.38, 95% CI, 0.19-0.73, p = 0.004). Severe stress hyperglycemia increased risks of 3-months all-cause mortality (OR, 2.82, 95% CI, 1.09-8.29, p = 0.041) and ICH (OR, 2.54, 95% CI, 1.21-5.50, p = 0.015). Conclusion: Stress hyperglycemia was associated with a reduced rate of excellent neurological outcomes, and increased mortality and ICH risks in patients with anterior circulation stroke after MT regardless of diabetes status.

15.
Front Public Health ; 9: 769687, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34746088

RESUMEN

This article takes the Guangdong Province of China as the research object and uses the difference-in-difference model to evaluate the impact of smart city construction on the quality of public occupational health and intercity differences. The obtained results show that smart city construction significantly improves the quality of public occupational health, and it is still valid after a series of robustness tests. The effect of this policy is stronger in cities that belong to the Pearl River Delta region or sub-provincial level cities. This study indicates that the central government should improve the pilot evaluation system and the performance appraisal mechanism of smart cities from the perspective of top-level design during the process of promoting smart city construction, which aims to correctly guide local governments to promote the construction of smart cities. To achieve the full improvement effect of smart city construction on the quality of public occupational health, local governments should implement smart city strategies in a purposeful and planned way according to the actual situation of the development of the jurisdiction.


Asunto(s)
Salud Laboral , China , Ciudades , Salud Pública , Ríos
16.
Elife ; 102021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-34165080

RESUMEN

ß- and γ-cytoplasmic actins are ubiquitously expressed in every cell type and are nearly identical at the amino acid level but play vastly different roles in vivo. Their essential roles in embryogenesis and mesenchymal cell migration critically depend on the nucleotide sequences of their genes, rather than their amino acid sequences; however, it is unclear which gene elements underlie this effect. Here we address the specific role of the coding sequence in ß- and γ-cytoplasmic actins' intracellular functions, using stable polyclonal populations of immortalized mouse embryonic fibroblasts with exogenously expressed actin isoforms and their 'codon-switched' variants. When targeted to the cell periphery using ß-actin 3'UTR; ß-actin and γ-actin have differential effects on cell migration. These effects directly depend on the coding sequence. Single-molecule measurements of actin isoform translation, combined with fluorescence recovery after photobleaching, demonstrate a pronounced difference in ß- and γ-actins' translation elongation rates in cells, leading to changes in their dynamics at focal adhesions, impairments in actin bundle formation, and reduced cell anchoring to the substrate during migration. Our results demonstrate that coding sequence-mediated differences in actin translation play a key role in cell migration.


Most mammalian cells make both ß- and γ-actin, two proteins which shape the cell's internal skeleton and its ability to migrate. The molecules share over 99% of their sequence, yet they play distinct roles. In fact, deleting the ß-actin gene in mice causes death in the womb, while the animals can survive with comparatively milder issues without their γ-actin gene. How two similar proteins can have such different biological roles is a long-standing mystery. A closer look could hold some clues: ß- and γ-actin may contain the same blocks (or amino acids), but the genetic sequences that encode these proteins differ by about 13%. This is because different units of genetic information ­ known as synonymous codons ­ can encode the same amino acid. These 'silent substitutions' have no effect on the sequence of the proteins, yet a cell reads synonymous codons (and therefore produces proteins) at different speeds. To find out the impact of silent substitutions, Vedula et al. swapped the codons for the two proteins, forcing mouse cells to produce ß-actin using γ-actin codons, and vice versa. Cells with non-manipulated γ-actin and those with ß-actin made using γ-actin codons could move much faster than cells with ß-actin. This suggested that silent substitutions were indeed affecting the role of the protein. Vedula et al. found that cells read γ-codons ­ and therefore made γ-actin ­ much more slowly than ß-codons: this also affected how quickly the protein could be dispatched where it was needed in the cell. Slower production meant that bundles of γ-actin were shorter, which allowed cells to move faster by providing a weaker anchoring system. Overall, this work provides new links between silent substitutions and protein behavior, a relatively new research area which is likely to shed light on other protein families.


Asunto(s)
Actinas/metabolismo , Movimiento Celular/fisiología , Biosíntesis de Proteínas/fisiología , Actinas/genética , Sustitución de Aminoácidos , Animales , Secuencia de Bases , Adhesiones Focales , Regulación de la Expresión Génica , Ratones , Isoformas de Proteínas , ARN Mensajero/genética , ARN Mensajero/metabolismo
17.
Sci Rep ; 11(1): 9376, 2021 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-33931669

RESUMEN

Regulator of G-protein signaling 7 (RGS7) is predominately present in the nervous system and is essential for neuronal signaling involving G-proteins. Prior studies in cultured cells showed that RGS7 is regulated via proteasomal degradation, however no protein is known to facilitate proteasomal degradation of RGS7 and it has not been shown whether this regulation affects G-protein signaling in neurons. Here we used a knockout mouse model with conditional deletion of arginyltransferase (Ate1) in the nervous system and found that in retinal ON bipolar cells, where RGS7 modulates a G-protein to signal light increments, deletion of Ate1 raised the level of RGS7. Electroretinographs revealed that lack of Ate1 leads to increased light-evoked response sensitivities of ON-bipolar cells, as well as their downstream neurons. In cultured mouse embryonic fibroblasts (MEF), RGS7 was rapidly degraded via proteasome pathway and this degradation was abolished in Ate1 knockout MEF. Our results indicate that Ate1 regulates RGS7 protein level by facilitating proteasomal degradation of RGS7 and thus affects G-protein signaling in neurons.


Asunto(s)
Aminoaciltransferasas/fisiología , Fibroblastos/metabolismo , Luz , Sistema Nervioso/metabolismo , Proteínas RGS/metabolismo , Células Bipolares de la Retina/metabolismo , Animales , Femenino , Fibroblastos/patología , Fibroblastos/efectos de la radiación , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Sistema Nervioso/patología , Sistema Nervioso/efectos de la radiación , Proteínas RGS/genética , Células Bipolares de la Retina/patología , Células Bipolares de la Retina/efectos de la radiación , Transducción de Señal
18.
Sci Rep ; 11(1): 6483, 2021 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-33753799

RESUMEN

This study compared the differences in the clinical manifestations, treatment courses and clinical turnover between mild and moderate coronavirus disease 2019 (COVID-19). Clinical data of the patients with imported COVID-19 admitted to Beijing Xiaotangshan Designated Hospital between March 15 and April 30, 2020, were retrospectively analysed. A total of 53 COVID-19 patients were included, with 21 mild and 32 moderate cases. Compared with the mild group, the moderate group showed significant differences in breathing frequency, lymphocyte count, neutrophil percentage, neutrophil/lymphocyte ratio, procalcitonin, C-reactive protein, and dynamic erythrocyte sedimentation rate. In the moderate group, 87.5% exhibited ground-glass opacities, 14% exhibited consolidative opacities, 53.1% exhibited local lesions and 68.8% exhibited unilateral lesions. The proportion of patients who received antiviral or antibiotic treatment in the moderate group was higher than that in the mild group, and the number of cases that progressed to severe disease in the moderate group was also significantly higher (18.7% vs. 0%, p = 0.035). Compared with patients with mild COVID-19, those with moderate COVID-19 exhibited more noticeable inflammatory reactions, more severe pulmonary imaging manifestations and earlier expression of protective antibodies. The overall turnover of the moderate cases was poorer than that of the mild cases.


Asunto(s)
COVID-19/patología , Adulto , Antivirales/uso terapéutico , Sedimentación Sanguínea , Proteína C-Reactiva/análisis , COVID-19/mortalidad , COVID-19/virología , China , Femenino , Humanos , Estimación de Kaplan-Meier , Pulmón/diagnóstico por imagen , Recuento de Linfocitos , Linfocitos/citología , Masculino , Persona de Mediana Edad , Neutrófilos/citología , Polipéptido alfa Relacionado con Calcitonina/análisis , Estudios Retrospectivos , SARS-CoV-2/aislamiento & purificación , Índice de Severidad de la Enfermedad , Adulto Joven , Tratamiento Farmacológico de COVID-19
19.
J Neurol ; 268(7): 2560-2569, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33555418

RESUMEN

OBJECTIVE: To investigate the safety and efficacy of intensive statin in the acute phase of ischemic stroke after intravenous thrombolysis therapy. METHODS: A total of 310 stroke patients treated with rt-PA were randomly scheduled into the intensive statin group (rosuvastatin 20 mg daily × 14 days) and the control group (rosuvastatin 5 mg daily × 14 days). The primary clinical endpoint was excellent functional outcome (mRS ≤ 1) at 3 months, and the primary safety endpoint was symptomatic intracranial hemorrhage (sICH) in 90 days. RESULTS: The intensive statin users did not achieve a favorable outcome in excellent functional outcome (mRS ≤ 1) at 3 months compared with controls (70.3% vs. 66.5%, p = 0.464). Intensive statin also not significantly improved the overall distribution of scores on the modified Rankin scale, as compared with controls (p = 0.82 by the Cochran-Mantel-Haenszel test). The incidence of primary safety endpoint events (sICH) in 90 days did not significantly differ between the intensive statin group and control group (0.6% vs. 1.3%, p > 0.999). CONCLUSION: The INSPIRE study indicated that intensive statin therapy may not improve clinical outcomes compared with the low dose of statin therapy in AIS patients undergoing intravenous thrombolysis, and the two groups had similar safety profile. CLINICAL TRIAL REGISTRATION: URL: http://www.chictr.org . Unique identifier: ChiCTR-IPR-16008642.


Asunto(s)
Isquemia Encefálica , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Isquemia Encefálica/complicaciones , Isquemia Encefálica/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Humanos , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica , Activador de Tejido Plasminógeno/uso terapéutico , Resultado del Tratamiento
20.
Front Cell Dev Biol ; 9: 807345, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35127722

RESUMEN

Arginylation is a post-translational modification mediated by the arginyltransferase (Ate1). We recently showed that conditional deletion of Ate1 in the nervous system leads to increased light-evoked response sensitivities of ON-bipolar cells in the retina, indicating that arginylation regulates the G-protein signaling complexes of those neurons and/or photoreceptors. However, none of the key players in the signaling pathway were previously shown to be arginylated. Here we show that Gαt1, Gß1, RGS6, and RGS7 are arginylated in the retina and RGS6 and RGS7 protein levels are elevated in Ate1 knockout, suggesting that arginylation plays a direct role in regulating their protein level and the G-protein-mediated responses in the retina.

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