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1.
Dev Biol ; 482: 67-81, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34896367

RESUMO

Cell fate changes during development, differentiation, and reprogramming are largely controlled at the transcription level. The DNA-binding transcription factors (TFs) often act in a combinatorial fashion to alter chromatin states and drive cell type-specific gene expression. Recent advances in fluorescent microscopy technologies have enabled direct visualization of biomolecules involved in the process of transcription and its regulatory events at the single-molecule level in living cells. Remarkably, imaging and tracking individual TF molecules at high temporal and spatial resolution revealed that they are highly dynamic in searching and binding cognate targets, rather than static and binding constantly. In combination with investigation using techniques from biochemistry, structure biology, genetics, and genomics, a more well-rounded view of transcription regulation is emerging. In this review, we briefly cover the technical aspects of live-cell single-molecule imaging and focus on the biological relevance and interpretation of the single-molecule dynamic features of transcription regulatory events observed in the native chromatin environment of living eukaryotic cells. We also discuss how these dynamic features might shed light on mechanistic understanding of transcription regulation.


Assuntos
Cromatina/metabolismo , Regulação da Expressão Gênica/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica/genética , Animais , DNA/biossíntese , Imagem Individual de Molécula , Análise de Célula Única
2.
J Neurosci Res ; 98(3): 481-490, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31670406

RESUMO

Luminopsins (LMOs) are chimeric proteins consisting of a luciferase fused to an opsin that provide control of neuronal activity, allowing for less cumbersome and less invasive optogenetic manipulation. It was previously shown that both an external light source and the luciferase substrate, coelenterazine (CTZ), could modulate activity of LMO-expressing neurons, although the magnitudes of the photoresponses remained subpar. In this study, we created an enhanced iteration of the excitatory luminopsin LMO3, termed eLMO3, that has improved membrane targeting due to the insertion of a Golgi trafficking signal sequence. In cortical neurons in culture, the expression of eLMO3 resulted in significant reductions in the formation of intracellular aggregates, as well as in a significant increase in total photocurrents. Furthermore, we corroborated the findings with injections of adeno-associated viral vectors into the deep layers of the somatosensory cortex (the barrel cortex) of male mice. We observed greatly reduced numbers of intracellular puncta in eLMO3-expressing cortical neurons compared to those expressing the original LMO3. Finally, we quantified CTZ-driven behavior, namely whisker-touching behavior, in male mice with LMO3 expression in the barrel cortex. After CTZ administration, mice with eLMO3 displayed significantly longer whisker responses than mice with LMO3. In summary, we have engineered the superior LMO by resolving membrane trafficking defects, and we demonstrated improved membrane targeting, greater photocurrents, and greater functional responses to stimulate with CTZ.


Assuntos
Imidazóis/administração & dosagem , Luciferases/metabolismo , Substâncias Luminescentes/administração & dosagem , Neurônios/metabolismo , Opsinas/metabolismo , Optogenética/métodos , Transporte Proteico , Pirazinas/administração & dosagem , Córtex Somatossensorial/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Feminino , Medições Luminescentes , Masculino , Potenciais da Membrana , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Cultura Primária de Células , Córtex Somatossensorial/efeitos dos fármacos
3.
Clin Chem Lab Med ; 57(5): 752-758, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-30496131

RESUMO

Background Proteinuria is a marker of poor outcomes in several diseases; however, few studies have been conducted to explore the prognostic value of proteinuria, assessed by urine dipstick test, for clinical outcomes in patients with type B acute aortic dissection (TBAD) undergoing thoracic endovascular aortic repair (TEVAR). Methods Consecutive patients with TBAD undergoing TEVAR were enrolled from January 2010 to July 2015. Proteinuria was defined as trace or higher, according to the results of urine dipstick testing. Associations among proteinuria and adverse events were evaluated. Results In total, 671 patients with a mean age of 44±15 years were included in the analysis. Proteinuria was detected in 281 patients (41.9%) before TEVAR. Multivariate logistic regression analysis showed that C-reactive protein and impaired renal function were independent predictors for proteinuria. During hospitalization, 21 patients died. In-hospital mortality was higher in patients with proteinuria (1.5% vs. 5.3%, p=0.005). After a median 3.4 years follow up, the post-TEVAR death rate was 10.4% (85 patients were lost to follow-up). The long-term cumulative mortality was significantly higher in patients with proteinuria (17.2% vs. 8.2%, log-rank=11.36, p=0.001). Multivariate Cox survival modeling indicated that proteinuria was significantly associated with long-term death, after adjustment for potential confounding risk factors (HR=1.92, p=0.012). Conclusions Pre-TEVAR proteinuria was identified as a prognostic marker in patients with TBAD and has potential for application as a convenient and simple risk assessment method before TEVAR.


Assuntos
Aorta Torácica/cirurgia , Dissecção Aórtica/diagnóstico , Proteinúria , Adulto , Idoso , Dissecção Aórtica/mortalidade , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/mortalidade , Procedimentos Endovasculares/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Resultado do Tratamento
4.
Front Neurol ; 15: 1380353, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38798711

RESUMO

Background and aim: Traumatic brain injury (TBI), a leading cause of high morbidity and mortality, represents a significant global public health challenge. Currently, no effective treatment for TBI exists. Curcumin, an active compound extracted from the root of Curcuma longa, has demonstrated neuroprotective properties both in vitro and in vivo. Notably, it has shown potential in reducing oxidative stress and inflammation and enhancing redox balance. This paper conducts a systematic review and meta-analysis to explore curcumin's role in TBI animal models extensively. The findings offer valuable insights for future human clinical trials evaluating curcumin as a therapeutic supplement or nutraceutical in TBI management. Methods: Comprehensive literature searches were conducted across MEDLINE, Embase, Cochrane, Web of Science, and Google Scholar databases. These searches aimed to identify relevant manuscripts in all languages, utilizing the keywords "curcumin" and "traumatic brain injury." Results: The final quantitative analysis included 18 eligible articles corresponding to animal studies. The analysis revealed that curcumin significantly reduced inflammatory cytokines, including IL-1ß (p = 0.000), IL-6 (p = 0.002), and TNF-α (p = 0.000), across various concentrations, time points, and administration routes. Additionally, curcumin markedly enhanced the activity of oxidative stress markers such as SOD (p = 0.000), Sir2 (p = 0.000), GPx (p = 0.000), and Nrf2 (p = 0.000), while reducing MDA (p = 0.000), 4-HNE (p = 0.001), and oxyprotein levels (p = 0.024). Furthermore, curcumin improved cerebral edema (p = 0.000) and upregulated neuroprotective factors like synapsin I (p = 0.019), BDNF (p = 0.000), and CREB (p = 0.000), without reducing mNSS (p = 0.144). About autophagy and apoptosis, curcumin increased the activity of Beclin-1 (p = 0.000) and Bcl-2 (p = 0.000), while decreasing caspase-3 (p = 0.000), the apoptosis index (p = 0.000), and P62 (p = 0.002). Conclusion: Curcumin supplementation positively affects traumatic brain injury (TBI) by alleviating oxidative stress and inflammatory responses and promoting neuroprotection. It holds potential as a therapeutic agent for human TBI. However, this conclusion necessitates further substantiation through high-quality literature and additional randomized controlled trials (RCTs). Systematic Review Registration: https://www.crd.york.ac.uk/prospero/. The registration number of PROSPERO: CRD42023452685.

5.
Cell Stem Cell ; 31(5): 694-716.e11, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38631356

RESUMO

Understanding cellular coordination remains a challenge despite knowledge of individual pathways. The RNA exosome, targeting a wide range of RNA substrates, is often downregulated in cellular senescence. Utilizing an auxin-inducible system, we observed that RNA exosome depletion in embryonic stem cells significantly affects the transcriptome and proteome, causing pluripotency loss and pre-senescence onset. Mechanistically, exosome depletion triggers acute nuclear RNA aggregation, disrupting nuclear RNA-protein equilibrium. This disturbance limits nuclear protein availability and hinders polymerase initiation and engagement, reducing gene transcription. Concurrently, it promptly disrupts nucleolar transcription, ribosomal processes, and nuclear exporting, resulting in a translational shutdown. Prolonged exosome depletion induces nuclear structural changes resembling senescent cells, including aberrant chromatin compaction, chromocenter disassembly, and intensified heterochromatic foci. These effects suggest that the dynamic turnover of nuclear RNA orchestrates crosstalk between essential processes to optimize cellular function. Disruptions in nuclear RNA homeostasis result in systemic functional decline, altering the cell state and promoting senescence.


Assuntos
Senescência Celular , Homeostase , RNA Nuclear , Animais , RNA Nuclear/metabolismo , Camundongos , Diferenciação Celular , Linhagem da Célula , Núcleo Celular/metabolismo , Transcriptoma/genética , Humanos
6.
Front Oncol ; 13: 1199556, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37664022

RESUMO

Introduction: Limb-salvage surgery has become the mainstream approaches for the treatment of sarcoma in the lower extremity. In cases where the sarcoma infiltrates the primary vessel, concurrent resection of the vessels and vascular reconstruction are required to ensure sufficient resection and preservation of limb function. The objective of this study is to assess the clinical outcomes of patients who underwent vascular reconstruction utilizing synthetic grafts for limb salvage, specifically in terms of postoperative complications and limb functional status. Methods: Between September 2016 and October 2021, 15 consecutive patients who underwent 15 arterial and 3 venous reconstruction procedures were included in this retrospective study. Incidence of postoperative morbidity, graft patency, rate of limb salvage, and overall survival of patients were analyzed. Results: The median follow-up was 12.5 months (range, 4.5-72.0). Graft thrombosis occurred in 5 patients (33.3%) and graft occlusion occurred in 3 patients (20.0%). The median overall survival was 28.0 months with the estimated 2-year and 5-year overall survival of 57.8% and 43.4% respectively. The 1-year and 2-year estimated patency rates of arterial reconstructions were 82.3% and 62.1%, respectively. None of the included patients with limb amputation were observed as a consequence of severe vascular complications, while two patients underwent amputation due to the repeat recurrence, resulting in a limb salvage rate of 86.7%. Conclusion: Our results show that the combination of vascular reconstruction and oncologic resection is a feasible option for preserving limbs in cases of musculoskeletal sarcoma with vessel involvement in the lower extremity. When vascular reconstruction surgery is performed, synthetic substitutes can be effectively used with low perioperative morbidity and an acceptable rate of limb salvage.

7.
IEEE J Biomed Health Inform ; 25(6): 2193-2203, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33170786

RESUMO

In 2019, outbreaks of vaccine-preventable diseases reached the highest number in the US since 1992. Medical misinformation, such as antivaccine content propagating through social media, is associated with increases in vaccine delay and refusal. Our overall goal is to develop an automatic detector for antivaccine messages to counteract the negative impact that antivaccine messages have on the public health. Very few extant detection systems have considered multimodality of social media posts (images, texts, and hashtags), and instead focus on textual components, despite the rapid growth of photo-sharing applications (e.g., Instagram). As a result, existing systems are not sufficient for detecting antivaccine messages with heavy visual components (e.g., images) posted on these newer platforms. To solve this problem, we propose a deep learning network that leverages both visual and textual information. A new semantic- and task-level attention mechanism was created to help our model to focus on the essential contents of a post that signal antivaccine messages. The proposed model, which consists of three branches, can generate comprehensive fused features for predictions. Moreover, an ensemble method is proposed to further improve the final prediction accuracy. To evaluate the proposed model's performance, a real-world social media dataset that consists of more than 30,000 samples was collected from Instagram between January 2016 and October 2019. Our 30 experiment results demonstrate that the final network achieves above 97% testing accuracy and outperforms other relevant models, demonstrating that it can detect a large amount of antivaccine messages posted daily. The implementation code is available at https://github.com/wzhings/antivaccine_detection.


Assuntos
Aprendizado Profundo , Mídias Sociais , Comunicação , Humanos , Saúde Pública
8.
Accid Anal Prev ; 151: 105962, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33385966

RESUMO

Reducing traffic fatal crashes has been an important mission of transportation. With the rapid development of sensor and Artificial Intelligence (AI) technologies, the computer vision (CV)-based crash anticipation in the near-crash phase is receiving growing attention. The ability to perceive fatal crash risks in an early stage is of paramount importance as well because it can improve the reliability of crash anticipation. Yet this task is challenging because it requires establishing a relationship between the driving scene information that CV can recognize and the fatal crash features that CV will not get until the crash occurrence. Image data with the annotation for directly training a reliable AI model for the early visual perception of fatal crash risks are not abundant. The Fatality Analysis Reporting System (FARS) contains big data on fatal crashes, which is a reliable data source for finding fatal crash clusters and discovering their distribution patterns to tell the association between driving scene characteristics and fatal crash features. To enhance CV's ability to perceive fatal crash risks earlier, this paper develops a data analytics model from fatal crash report data, which is named scenario-wise, spatio-temporal attention guidance. First, the paper identifies five descriptive variables that are sparse and thus allow for decomposing the 5-year (2013-2017) fatal crash dataset to develop scenario-wise attention guidance. Then, an exploratory analysis of location- and time-related descriptive variables suggests dividing fatal crashes into spatially defined groups. A group's temporal distribution pattern is an indicator of the similarity of fatal crashes in the group. Hierarchical clustering and K-means clustering further merge the spatially defined groups into six clusters according to the similarity of their temporal patterns. After that, association rule mining discovers the statistical relationship between the temporal information of driving scenes with fatal crash features, such as the first harmful event and the manner of collisions, for each cluster. The paper illustrates how the developed attention guidance supports the design and implementation of a preliminary CV model that can identify agents of a possibility to involve in fatal crashes from their environmental and context information.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Inteligência Artificial , Computadores , Análise de Dados , Reprodutibilidade dos Testes , Percepção Visual
9.
Int J Gynecol Cancer ; 20(7): 1240-3, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21495238

RESUMO

AIMS: This study was performed to determine whether the incidence of cervical cancer in women aged 35 or younger has changed for the past 30 years and to examine the clinical characteristics of the cases. METHODS: The clinical and pathological data of 6257 patients with cervical cancer treated between January 1975 and December 2009 were retrospectively analyzed. RESULTS: The prevalence of young (≤ 35 years old) patients steadily increased from 2.8% to 15.7% for the past 30 years. The ratio of adenocarcinoma also rose from 1975-1979 to 2005-2009. In an analysis by age group, in group A, adenocarcinoma was found in 17% (≤ 35 years old); in group B, 7.1% (> 35 years old) [χ² = 78.92, P < 0.0001]. The clinical presentation presented showed that 36.4% of patients presented mainly postcoital bleeding in group A, whereas the symptom of irregular genital bleeding predominated in group B (P < 0.0001). The patients detected by routine cytological screening in group A (8.7%) were more than the patients in group B (3%). CONCLUSIONS: The prevalence of cervical cancer in young women has been increasing steadily in Hubei, China. It is necessary for all sexually active women and women aged 35 years or even younger to undergo cervical cancer screening.


Assuntos
Adenocarcinoma/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adenocarcinoma/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/epidemiologia , China/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Neoplasias do Colo do Útero/epidemiologia , Esfregaço Vaginal , Adulto Jovem
10.
J Interv Med ; 2(4): 146-149, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34805891

RESUMO

PURPOSE: The aim of this study was to evaluate the clinical effects of the Trivex system in the treatment of primary severe superficial varicose veins of the lower extremity and compare Trivex to the point-form-stripping combined with foam sclerotherapy (FS). METHODS: A total of 64 patients (35 females, 29 males; mean age, 57 ±â€¯11 years [range, 29-79 years]) with primary severe superficial varicose veins of the lower extremity involving 64 legs were included between October 2015 and July 2019. The maximum diameter of the vein branches was >20 mm, which appeared to be cystic dilatation and forms large-scale in the crus or the thigh. All patients underwent high ligation and endovenous laser ablation or stripping of the trunk under general anesthesia. The surgical time, pain/phlebitis, number of incisions, amount of bleeding, recurrence of varicose vein, incidence of surgical site infections (SSIs), satisfaction score, and improvement in clinical symptoms were evaluated respectively with the patients in two groups: Group A, with patients who underwent treatment with the Trivex system, and Group B, patients who underwent treatment by point-form-stripping combined with FS. RESULTS: All procedures were performed successfully. The average operative time in Group A was 56 ±â€¯11 min, whereas that of Group B was 90 ±â€¯33 min, which was a significant difference (p < 0.05). Group A patients felt little pain after surgery, whereas in Group B the level of pain peaked on postoperative day 30, mostly due to thrombophlebitis after FS. There was no recurrence of varicose vein was observed in any patient, however, there were some residual effects in Group B, including the amount of bleeding volume, in-hospital stays, pain/phlebitis, and number of incisions (P < 0.05). There were no significant differences with respect to SSIs, improvement in clinical symptoms, and satisfaction scores observed (p>0.05). CONCLUSIONS: This study shows that patients benefited from both treatment options. However, primary severe superficial varicose veins of the lower extremity treated with the Trivex system suffered less pain with fewer incisions than severe branches treated with the point-form-stripping combined with foam sclerotherapy (FS). In summary, the Trivex system is a suitable treatment prior to point-form-stripping combined with foam sclerotherapy (FS) for those who demand a high level of appearance, and especially for young patients, the Trivex system is recommended.

11.
Water Res ; 84: 198-206, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26233659

RESUMO

Although the identification of effective oxidant species has been extensively studied, yet the subcellular mechanism of bacterial inactivation has never been clearly elucidated in electrochemical disinfection processes. In this study, subcellular mechanism of Escherichia coli inactivation during electrochemical disinfection was revealed in terms of comprehensive factors such as cell morphology, total organic components, K(+) leakage, membrane permeability, lipid peroxidation, membrane potential, membrane proteins, intracellular enzyme, cellular ATP level and DNA. The electrolysis was conducted with boron-doped diamond anode in three electrolytes including chloride, sulfate and phosphate. Results demonstrated that cell inactivation was mainly attributed to damage to the intracellular enzymatic systems in chloride solution. In sulfate solution, certain essential membrane proteins like the K(+) ion transport systems were eliminated. Thus, the pronounced K(+) leakage from cytosol resulted in gradual collapse of the membrane potential, which would hinder the subcellular localization of cell division-related proteins as well as ATP synthesis and thereby lead to the bacterial inactivation. Remarkable lipid peroxidation was observed, while the intracellular damage was negligible. In phosphate solution, the cells sequentially underwent overall destruction as a whole cell with no captured intermediate state, during which the organic components of the cells were mostly subjected to mineralization. This study provided a thorough insight into the bacterial inactivation mechanism on the subcellular level.


Assuntos
Boro/toxicidade , Diamante/química , Escherichia coli/efeitos dos fármacos , Boro/química , Desinfecção , Técnicas Eletroquímicas , Eletrodos , Eletrólitos
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