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1.
Sci Rep ; 14(1): 12418, 2024 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816453

RESUMO

Body core temperature (Tc) monitoring is crucial for minimizing heat injury risk. However, validated strategies are invasive and expensive. Although promising, aural canal temperature (Tac) is susceptible to environmental influences. This study investigated whether incorporation of external auricle temperature (Tea) into an ear-based Tc algorithm enhances its accuracy during multiple heat stress conditions. Twenty males (mean ± SD; age = 25 ± 3 years, BMI = 21.7 ± 1.8, body fat = 12 ± 3%, maximal aerobic capacity (VO2max) = 64 ± 7 ml/kg/min) donned an ear-based wearable and performed a passive heating (PAH), running (RUN) and brisk walking trial (WALK). PAH comprised of immersion in hot water (42.0 ± 0.3 °C). RUN (70 ± 3%VO2max) and WALK (50 ± 10%VO2max) were conducted in an environmental chamber (Tdb = 30.0 ± 0.2 °C, RH = 71 ± 2%). Several Tc models, developed using Tac, Tea and heart rate, were validated against gastrointestinal temperature. Inclusion of Tea as a model input improved the accuracy of the ear-based Tc algorithm. Our best performing model (Trf3) displayed good group prediction errors (mean bias error = - 0.02 ± 0.26 °C) but exhibited individual prediction errors (percentage target attainment ± 0.40 °C = 88%) that marginally exceeded our validity criterion. Therefore, Trf3 demonstrates potential utility for group-based Tc monitoring, with additional refinement needed to extend its applicability to personalized heat strain monitoring.


Assuntos
Temperatura Corporal , Pavilhão Auricular , Temperatura Alta , Dispositivos Eletrônicos Vestíveis , Humanos , Masculino , Adulto , Temperatura Corporal/fisiologia , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Pavilhão Auricular/fisiologia , Adulto Jovem , Frequência Cardíaca/fisiologia , Algoritmos
2.
Sci Rep ; 14(1): 11237, 2024 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755283

RESUMO

Osteoarthritis (OA) is the most prevalent form of arthritis, characterized by a complex pathogenesis. One of the key factors contributing to its development is the apoptosis of chondrocytes triggered by oxidative stress. Involvement of peroxisome proliferator-activated receptor gamma (PPARγ) has been reported in the regulation of oxidative stress. However, there remains unclear mechanisms that through which PPARγ influences the pathogenesis of OA. The present study aims to delve into the role of PPARγ in chondrocytes apoptosis induced by oxidative stress in the context of OA. Primary human chondrocytes, both relatively normal and OA, were isolated and cultured for the following study. Various assessments were performed, including measurements of cell proliferation, viability and cytotoxicity. Additionally, we examined cell apoptosis, levels of reactive oxygen species (ROS), nitric oxide (NO), mitochondrial membrane potential (MMP) and cytochrome C release. We also evaluated the expression of related genes and proteins, such as collagen type II (Col2a1), aggrecan, inducible nitric oxide synthase (iNOS), caspase-9, caspase-3 and PPARγ. Compared with relatively normal cartilage, the expression of PPARγ in OA cartilage was down-regulated. The proliferation of OA chondrocytes decreased, accompanied by an increase in the apoptosis rate. Down-regulation of PPARγ expression in OA chondrocytes coincided with an up-regulation of iNOS expression, leading to increased secretion of NO, endogenous ROS production, and decrease of MMP levels. Furthermore, we observed the release of cytochrome C, elevated caspase-9 and caspase-3 activities, and reduction of the components of extracellular matrix (ECM) Col2a1 and aggrecan. Accordingly, utilization of GW1929 (PPARγ Agonists) or Z-DEVD-FMK (caspase-3 inhibitor) can protect chondrocytes from mitochondrial-related apoptosis and alleviate the progression of OA. During the progression of OA, excessive oxidative stress in chondrocytes leads to apoptosis and ECM degradation. Activation of PPARγ can postpone OA by down-regulating caspase-3-dependent mitochondrial apoptosis pathway.


Assuntos
Apoptose , Caspase 3 , Condrócitos , Mitocôndrias , Osteoartrite , PPAR gama , Espécies Reativas de Oxigênio , Humanos , Condrócitos/metabolismo , Condrócitos/patologia , PPAR gama/metabolismo , Caspase 3/metabolismo , Osteoartrite/metabolismo , Osteoartrite/patologia , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo , Potencial da Membrana Mitocondrial , Proliferação de Células , Óxido Nítrico/metabolismo , Células Cultivadas , Pessoa de Meia-Idade , Idoso , Feminino , Masculino
3.
Biomed Pharmacother ; 175: 116706, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38713944

RESUMO

Excessive oxidative stress and NLRP3 inflammasome activation are considered the main drivers of inflammatory bowel disease (IBD), and inhibition of inflammasomes ameliorates clinical symptoms and morphological manifestations of IBD. Herein, we examined the roles of NLRP3 activation in IBD and modulation of NLRP3 by sulforaphane (SFN), a compound with multiple pharmacological activities that is extracted from cruciferous plants. To simulate human IBD, we established a mouse colitis model by administering dextran sodium sulfate in the drinking water. SFN (25, 50 mg·kg-1·d-1, ig) or the positive control sulfasalazine (500 mg/kg, ig) was administered to colitis-affected mice for 7 days. Model mice displayed pathological alterations in colon tissue as well as classic symptoms of colitis beyond substantial tissue inflammation. Expression of NLRP3, ASC, and caspase-1 was significantly elevated in the colonic epithelium. The expression of NLRP3 inflammasomes led to activation of downstream proteins and increases in the cytokines IL-18 and IL-1ß. SFN administration either fully or partially reversed these changes, thus restoring IL-18 and IL-1ß, substantially inhibiting NLRP3 activation, and decreasing inflammation. SFN alleviated the inflammation induced by LPS and NLRP3 agonists in RAW264.7 cells by decreasing the levels of reactive oxygen species. In summary, our results revealed the pathological roles of oxidative stress and NLRP3 in colitis, and indicated that SFN might serve as a natural NLRP3 inhibitor, thereby providing a new strategy for alternative colitis treatment.


Assuntos
Colite Ulcerativa , Modelos Animais de Doenças , Inflamassomos , Isotiocianatos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR , Estresse Oxidativo , Sulfóxidos , Animais , Isotiocianatos/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Sulfóxidos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Colite Ulcerativa/induzido quimicamente , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Camundongos , Masculino , Sulfato de Dextrana , Colo/efeitos dos fármacos , Colo/patologia , Colo/metabolismo , Células RAW 264.7
4.
Gut ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816188

RESUMO

OBJECTIVE: Hirschsprung disease (HSCR) is a severe congenital disorder affecting 1:5000 live births. HSCR results from the failure of enteric nervous system (ENS) progenitors to fully colonise the gastrointestinal tract during embryonic development. This leads to aganglionosis in the distal bowel, resulting in disrupted motor activity and impaired peristalsis. Currently, the only viable treatment option is surgical resection of the aganglionic bowel. However, patients frequently suffer debilitating, lifelong symptoms, with multiple surgical procedures often necessary. Hence, alternative treatment options are crucial. An attractive strategy involves the transplantation of ENS progenitors generated from human pluripotent stem cells (hPSCs). DESIGN: ENS progenitors were generated from hPSCs using an accelerated protocol and characterised, in detail, through a combination of single-cell RNA sequencing, protein expression analysis and calcium imaging. We tested ENS progenitors' capacity to integrate and affect functional responses in HSCR colon, after ex vivo transplantation to organotypically cultured patient-derived colonic tissue, using organ bath contractility. RESULTS: We found that our protocol consistently gives rise to high yields of a cell population exhibiting transcriptional and functional hallmarks of early ENS progenitors. Following transplantation, hPSC-derived ENS progenitors integrate, migrate and form neurons/glia within explanted human HSCR colon samples. Importantly, the transplanted HSCR tissue displayed significantly increased basal contractile activity and increased responses to electrical stimulation compared with control tissue. CONCLUSION: Our findings demonstrate, for the first time, the potential of hPSC-derived ENS progenitors to repopulate and increase functional responses in human HSCR patient colonic tissue.

5.
Elife ; 122024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713053

RESUMO

Uncovering the regulators of cellular aging will unravel the complexity of aging biology and identify potential therapeutic interventions to delay the onset and progress of chronic, aging-related diseases. In this work, we systematically compared genesets involved in regulating the lifespan of Saccharomyces cerevisiae (a powerful model organism to study the cellular aging of humans) and those with expression changes under rapamycin treatment. Among the functionally uncharacterized genes in the overlap set, YBR238C stood out as the only one downregulated by rapamycin and with an increased chronological and replicative lifespan upon deletion. We show that YBR238C and its paralog RMD9 oppositely affect mitochondria and aging. YBR238C deletion increases the cellular lifespan by enhancing mitochondrial function. Its overexpression accelerates cellular aging via mitochondrial dysfunction. We find that the phenotypic effect of YBR238C is largely explained by HAP4- and RMD9-dependent mechanisms. Furthermore, we find that genetic- or chemical-based induction of mitochondrial dysfunction increases TORC1 (Target of Rapamycin Complex 1) activity that, subsequently, accelerates cellular aging. Notably, TORC1 inhibition by rapamycin (or deletion of YBR238C) improves the shortened lifespan under these mitochondrial dysfunction conditions in yeast and human cells. The growth of mutant cells (a proxy of TORC1 activity) with enhanced mitochondrial function is sensitive to rapamycin whereas the growth of defective mitochondrial mutants is largely resistant to rapamycin compared to wild type. Our findings demonstrate a feedback loop between TORC1 and mitochondria (the TORC1-MItochondria-TORC1 (TOMITO) signaling process) that regulates cellular aging processes. Hereby, YBR238C is an effector of TORC1 modulating mitochondrial function.


Assuntos
Senescência Celular , Mitocôndrias , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Transdução de Sinais , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/genética , Senescência Celular/genética , Sirolimo/farmacologia , Regulação Fúngica da Expressão Gênica , Deleção de Genes , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/genética
6.
Acta Pharmacol Sin ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811775

RESUMO

Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to the epidermal growth factor precursor homologous domain A (EGF-A) of low-density lipoprotein receptor (LDLR) in the liver and triggers the degradation of LDLR via the lysosomal pathway, consequently leading to an elevation in plasma LDL-C levels. Inhibiting PCSK9 prolongs the lifespan of LDLR and maintains cholesterol homeostasis in the body. Thus, PCSK9 is an innovative pharmacological target for treating hypercholesterolemia and atherosclerosis. In this study, we discovered that E28362 was a novel small-molecule PCSK9 inhibitor by conducting a virtual screening of a library containing 40,000 compounds. E28362 (5, 10, 20 µM) dose-dependently increased the protein levels of LDLR in both total protein and the membrane fraction in both HepG2 and AML12 cells, and enhanced the uptake of DiI-LDL in AML12 cells. MTT assay showed that E28362 up to 80 µM had no obvious toxicity in HepG2, AML12, and HEK293a cells. The effects of E28362 on hyperlipidemia and atherosclerosis were evaluated in three different animal models. In high-fat diet-fed golden hamsters, administration of E28362 (6.7, 20, 60 mg·kg-1·d-1, i.g.) for 4 weeks significantly reduced plasma total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C) and PCSK9 levels, and reduced liver TC and TG contents. In Western diet-fed ApoE-/- mice (20, 60 mg·kg-1·d-1, i.g.) and human PCSK9 D374Y overexpression mice (60 mg·kg-1·d-1, i.g.), administration of E28362 for 12 weeks significantly decreased plasma LDL-C levels and the area of atherosclerotic lesions in en face aortas and aortic roots. Moreover, E28362 significantly increased the protein expression level of LDLR in the liver. We revealed that E28362 selectively bound to PCSK9 in HepG2 and AML12 cells, blocked the interaction between LDLR and PCSK9, and induced the degradation of PCSK9 through the ubiquitin-proteasome pathway, which finally resulted in increased LDLR protein levels. In conclusion, E28362 can block the interaction between PCSK9 and LDLR, induce the degradation of PCSK9, increase LDLR protein levels, and alleviate hyperlipidemia and atherosclerosis in three distinct animal models, suggesting that E28362 is a promising lead compound for the treatment of hyperlipidemia and atherosclerosis.

7.
Parasitol Res ; 123(4): 189, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639821

RESUMO

Toxocara canis is a parasitic zoonose that is distributed worldwide and is one of the two pathogens causing toxocariasis. After infection, it causes serious public health and safety problems, which pose significant veterinary and medical challenges. To better understand the regulatory effects of T. canis infection on the host immune cells, murine macrophages (RAW264.7) were incubated with recombinant T. canis C-type lectin 4 (rTc-CTL-4) protein in vitro. The quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were used to analyze the nucleotide-binding oligomerization domain-containing protein 1/2 (NOD1/2), receptor-interacting protein 2 (RIP2), nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB), and mitogen-activated protein kinase (MAPK) on mRNA level and protein expression level in macrophages. Our results indicated that 10 µg/mL rTc-CTL-4 protein could modulate the expression of NOD1, NOD2, and RIP2 at both the transcriptional and translational levels. The protein translation levels of NF-κB, P-p65, p38, and P-p38 in macrophages were also modulated by rTc-CTL-4 protein. Macrophages were co-incubated with rTc-CTL-4 protein after siRNA silencing of NOD1, NOD2, and RIP2. The expression levels of NF-κB, P-p65, p38, and P-p38 were significantly changed compared with the negative control groups (Neg. Ctrl.). Taken together, rTc-CTL-4 protein seemed to act on NOD1/2-RIP2-NF-κB and MAPK signaling pathways in macrophages and might activate MAPK and NF-κB signaling pathways by regulating NOD1, NOD2, and RIP2. The insights from the above studies could contribute to our understanding of immune recognition and regulatory mechanisms of T. canis infection in the host animals.


Assuntos
NF-kappa B , Toxocara canis , Animais , Camundongos , NF-kappa B/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Toxocara canis/metabolismo , Transdução de Sinais/fisiologia , Macrófagos
8.
Dermatitis ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563786

RESUMO

Background: Mutations in filaggrin (FLG), the gene that codes for the skin barrier protein, have been shown to be associated with atopic dermatitis (AD). Objective: The objectives of this study were to determine the effects of genetic counseling and parental education on infants at a high risk of AD. Methods: We enrolled 7521 newborns in Taiwan from January 1, 2016, to March 30, 2020, and all of them received genetic testing encompassing 20 known FLG mutations. The genetic counseling and AD prevention and care team consisted of pediatricians, dermatologists, social workers, and genetic counselors. The counseling was arranged for at least 30 minutes within 45 days after delivery. Results: A total of 2963 high-risk infants (39.4%) were identified. Homozygous c.1432C>T was the most commonly identified mutation. A total of 418 neonates' parents were stratified into counseling and noncounseling groups, where the effect of parental education was evaluated. The genetically stratified parental education program was effective in preventing AD development by 63.3% in high-risk infants before 12 months of life (P < 0.0001). Conclusion: Genetic stratification and parental education are effective in preventing the development of AD in high-risk infants before 12 months of life.

9.
Heliyon ; 10(7): e28959, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601542

RESUMO

Stroke represents a significant threat to global human health, characterized by high rates of morbidity, disability, and mortality. Predominantly, strokes are ischemic in nature. Ischemic stroke (IS) is influenced by various cell death pathways, notably autophagy and ferroptosis. Recent studies have increasingly highlighted the interplay between autophagy and ferroptosis, a process likely driven by the accumulation of reactive oxygen species (ROS). Post-IS, either the inhibition of autophagy or its excessive activation can escalate ROS levels. Concurrently, the interaction between ROS and lipids during ferroptosis further augments ROS accumulation. Elevated ROS levels can provoke endoplasmic reticulum stress-induced autophagy and, in conjunction with free iron (Fe2+), can trigger ferroptosis. Moreover, ROS contribute to protein and lipid oxidation, endothelial dysfunction, and an inflammatory response, all of which mediate secondary brain injury following IS. This review succinctly explores the mechanisms of ROS-mediated crosstalk between autophagy and ferroptosis and the detrimental impact of increased ROS on IS. It also offers novel perspectives for IS treatment strategies.

10.
World J Clin Cases ; 12(8): 1461-1466, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38576819

RESUMO

BACKGROUND: Appendiceal intussusception is a pathological condition in which the appendix is inverted into the cecum, which may cause symptoms that resemble those of other gastrointestinal disorders and may induce intestinal obstruction. The rarity of this case presentation is the co-occurrence of appendiceal intussusception and cecal adenocarcinoma, a combination that to our knowledge has not previously been reported in the medical literature. This case provides new insights into the complexities of diagnosing and managing overlapping pathologies. CASE SUMMARY: A 25-year-old woman presented with persistent periumbilical pain and bloody stools. An initial biopsy showed cecal cancer; however, subsequent colonoscopy and computed tomography findings raised the suspicion of appendiceal intussusception, which was later confirmed postoperatively. This unique case was characterized by a combination of intussusception and adenocarcinoma of the cecum. The intervention included a laparoscopic right hemicolectomy, which led to the histopathological diagnosis of mucinous adenocarcinoma with appendiceal intussusception. The patient recovered well postoperatively and was advised to initiate adjuvant chemotherapy. This case highlights not only the importance of considering appendiceal intussusception in the differential diagnosis, but also the possibility of appendicitis and the atypical presentation of neoplastic lesions. CONCLUSIONS: Physicians should consider the possibility of appendiceal intussusception in cases of atypical appendicitis, particularly when associated with neoplastic presentation.

11.
Cardiovasc Diabetol ; 23(1): 133, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654269

RESUMO

BACKGROUND: Metabolic syndrome (MetS) can increase the risk of morbidity and mortality of cardiovascular disease and obstructive coronary artery disease (OCAD), which usually have a poor prognosis. This study aimed to explore the impact of MetS on left ventricular (LV) deformation and function in OCAD patients and investigate the independent factors of impaired LV function and deformation. MATERIALS AND METHODS: A total of 121 patients with OCAD and 52 sex- and age-matched controls who underwent cardiac magnetic resonance scanning were enrolled in the study. All OCAD patients were divided into two groups: OCAD with MetS [OCAD(MetS+), n = 83] and OCAD without MetS [OCAD(MetS-), n = 38]. LV functional and global strain parameters were measured and compared among the three groups. Multivariable linear regression analyses were constructed to investigate the independent factors of LV impairment in OCAD patients. Logistic regression analysis and receiver operating characteristic (ROC) curve analysis were performed to test the prediction efficiency of MetS for LV impairment. RESULTS: From controls to the OCAD(MetS-) group to the OCAD(MetS+) group, LV mass (LVM) increased, and LV global function index (LVGFI) and LV global longitudinal peak strain (GLPS) decreased (all p < 0.05). Compared with the OCAD(MetS-) group, the LV GLPS declined significantly (p = 0.027), the LVM increased (p = 0.006), and the LVGFI decreased (p = 0.043) in the OCAD(MetS+) group. After adjustment for covariates in OCAD patients, MetS was an independent factor of decreased LV GLPS (ß = - 0.211, p = 0.002) and increased LVM (ß = 0.221, p = 0.003). The logistic multivariable regression analysis and ROC analysis showed that combined MetS improved the efficiency of predicting LV GLPS reduction (AUC = 0.88) and LVM (AUC = 0.89) increase. CONCLUSIONS: MetS aggravated the damage of LV deformation and function in OCAD patients and was independently associated with LV deformation and impaired LV strain. Additionally, MetS increased the prediction efficiency of increased LVM and decreased LV GLPS. Early detection and intervention of MetS in patients with OCAD is of great significance.


Assuntos
Síndrome Metabólica , Valor Preditivo dos Testes , Disfunção Ventricular Esquerda , Função Ventricular Esquerda , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Síndrome Metabólica/fisiopatologia , Síndrome Metabólica/complicações , Síndrome Metabólica/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Idoso , Estudos de Casos e Controles , Medição de Risco , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/complicações , Imagem Cinética por Ressonância Magnética , Fatores de Risco , Prognóstico , Estenose Coronária/fisiopatologia , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/complicações
12.
Angew Chem Int Ed Engl ; : e202404213, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600431

RESUMO

Electrocatalytic carbon dioxide/carbon monoxide reduction reaction (CO(2)RR) has emerged as a prospective and appealing strategy to realize carbon neutrality for manufacturing sustainable chemical products. Developing highly active electrocatalysts and stable devices has been demonstrated as effective approach to enhance the conversion efficiency of CO(2)RR. In order to rationally design electrocatalysts and devices, a comprehensive understanding of the intrinsic structure evolution within catalysts and micro-environment change around electrode interface, particularly under operation conditions, is indispensable. Synchrotron radiation has been recognized as a versatile characterization platform, garnering widespread attention owing to its high brightness, elevated flux, excellent directivity, strong polarization and exceptional stability. This review systematically introduces the applications of synchrotron radiation technologies classified by radiation sources with varying wavelengths in CO(2)RR. By virtue of in situ/operando synchrotron radiationanalytical techniques, we also summarize relevant dynamic evolution processes from electronic structure, atomic configuration, molecular adsorption, crystal lattice and devices, spanning scales from the angstrom to the micrometer. The merits and limitations of diverse synchrotron characterization techniques are summarized, and their applicable scenarios in CO(2)RR are further presented. On the basis of the state-of-the-art fourth-generation synchrotron facilities, a perspective for further deeper understanding of the CO(2)RR process using synchrotron radiation analytical techniques is proposed.

13.
ACS Chem Neurosci ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634698

RESUMO

Neuronal death resulting from ischemic stroke is the primary cause of adult mortality and disability, and effective neuroprotective agents for poststroke intervention are still lacking. Remote ischemic postconditioning (RIPostC) has demonstrated significant protective effects against ischemia in various organs; however, the specific mechanisms are not fully understood. This study investigated the potential neuroprotective mechanisms of RIPostC in the context of ischemic stroke. Using a rat model of middle cerebral artery occlusion, we found that RIPostC mitigated neurological damage, improved movement in the open-field test, and protected against neuronal apoptosis. In terms of energy metabolism, RIPostC enhanced ATP levels, suppressed lactate content, and increased the production of ketone bodies (KBs). In the ferroptosis assay, RIPostC protected against lipoperoxidation, reversed the reduction of glutathione peroxidase 4 (GPX4), and mitigated the excessive expression of long-chain acyl-CoA synthetase family member 4 (ACSL4). In oxygen-glucose deprivation/reoxygenation-treated HT22 cells, KBs maintained GPX4 levels, suppressed ACSL4 expression, and preserved the mitochondrial cristae number. However, the effect of KBs on the expression of GPX4, ACSL4, and the number of mitochondrial cristae was blocked by erastin. Moreover, both RIPostC and KBs reduced total iron and ferrous ion content by repressing iron transporters both in vitro and in vivo. In conclusion, KBs-induced mitigation of ferroptosis could represent a new therapeutic mechanism for RIPostC in treating stroke.

14.
Biochem Biophys Res Commun ; 714: 149964, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38669753

RESUMO

Human DDX3X, an important member of the DEAD-box family RNA helicases, plays a crucial role in RNA metabolism and is involved in cancer development, viral infection, and neurodegenerative disease. Although there have been many studies on the physiological functions of human DDX3X, issues regarding its exact targets and mechanisms of action remain unclear. In this study, we systematically characterized the biochemical activities and substrate specificity of DDX3X. The results demonstrate that DDX3X is a bidirectional RNA helicase to unwind RNA duplex and RNA-DNA hybrid driven by ATP. DDX3X also has nucleic acid annealing activity, especially for DNA. More importantly, it can function as a typical nucleic acid chaperone which destabilizes highly structured DNA and RNA in an ATP-independent manner and promotes their annealing to form a more stable structure. Further truncation mutations confirmed that the highly disordered N-tail and C-tail are critical for the biochemical activities of DDX3X. They are functionally complementary, with the N-tail being crucial. These results will shed new light on our understanding of the molecular mechanism of DDX3X in RNA metabolism and DNA repair, and have potential significance for the development of antiviral/anticancer drugs targeting DDX3X.


Assuntos
Trifosfato de Adenosina , RNA Helicases DEAD-box , Chaperonas Moleculares , Humanos , Trifosfato de Adenosina/metabolismo , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/genética , DNA/metabolismo , DNA/química , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , RNA/metabolismo , RNA/química , RNA/genética , Especificidade por Substrato
15.
ACS Omega ; 9(9): 10517-10521, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38463289

RESUMO

Tungsten (W) is an extremely rare and vital metal extensively used in metallurgy, the chemical industry, optoelectronic devices, and machinery manufacturing. In this work, an environmentally friendly and efficient physical method based on photon-phonon resonance absorption (PPRA) is proposed for separating W from scheelite. We calculated the vibrational spectrum of calcium tungstate (CaWO4) and assigned the infrared (IR) absorption and Raman scattering peaks through a dynamic analysis of the normal modes. We focused on the strong IR absorption peaks related to W and identified three high-intensity IR-active modes at around 830 cm-1, corresponding to the stretching of the W-O bonds. Therefore, we propose the use of high-power terahertz (∼25 THz) laser radiation to facilitate W extraction from compounds, leveraging the high efficiency of PPRA. Experimental testing is required to determine the precise absorption frequency under industrial production conditions.

16.
J AAPOS ; 28(2): 103861, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38442849

RESUMO

PURPOSE: To evaluate the surgical effect of the Wright central plication on vertical rectus muscles to correct vertical strabismus. METHODS: In this multicenter, retrospective, observational outcomes study, data were collected from two surgeons in different practice settings (2017-22). All patients who underwent vertical rectus central plication were included; those undergoing any concurrent strabismus surgery for vertical strabismus were excluded. Primary outcome was amount of strabismus correction in prism diopters per vertical rectus central plication. Secondary outcome was to determine factors associated with better or worse surgical outcomes and patient and patient responses. Data were analyzed using descriptive and bivariate statistics. RESULTS: A total of 36 patients were included. Mean age was 60 years. Mean follow-up was 8.4 months. Of the 36 patients, 11 (31%) had idiopathic strabismus, and 7 (19%) had congenital superior oblique palsy. The remainder had a history that included prior ocular surgery, trauma, and Brown syndrome; 16 (44 %) had prior strabismus surgery. Of 31 patients with preoperative diplopia, 23 (74%) had postoperative resolution of diplopia, and 10 of 16 patients with preoperative prisms (63%) no longer required prisms postoperatively. Mean vertical deviation change was 4.7Δ. Subgroup analysis removing patients with congenital superior oblique palsy showed a larger response of 5.5Δ. 78% of patients had a final deviation <5Δ. No complications or induced postoperative diplopia was reported. CONCLUSIONS: In our study cohort, vertical rectus central plication corrected approximately 5Δ (range, 4.5Δ-5.5Δ) of vertical strabismus due to a variety of causes.


Assuntos
Procedimentos Cirúrgicos Oftalmológicos , Estrabismo , Humanos , Pessoa de Meia-Idade , Diplopia/etiologia , Diplopia/cirurgia , Estudos Retrospectivos , Estrabismo/etiologia , Estrabismo/cirurgia , Músculos Oculomotores/cirurgia , Paralisia/cirurgia , Resultado do Tratamento
17.
Injury ; 55(6): 111482, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38461103

RESUMO

BACKGROUND: This study aimed to assess the clinical epidemiological characteristics of children with electrical injuries and discuss the countermeasures for the prevention of electrical injuries in children. METHODS: The children with electrical injuries were grouped according to whether or not they were admitted to the hospital for treatment into inpatient and outpatient groups. Clinical data such as gender, causes of injury and injury-causing voltage distribution in different age groups were analyzed. The factors affecting hospitalization were subjected to χ2 test, Kruskal-Wallis H test, and logistic regression analysis. RESULTS: A total of 321 children were included with 37 divided into inpatient group and 284 divided into outpatient group. The incidence of electrical injuries was highest in children ≤6 years old and in the summer. There were significantly different in gender, place of occurrence, cause of injury and injury-causing voltage between the two groups (p < 0.05). Injury-causing voltage is an independent risk factor affecting hospitalization of children with electrical injuries (OR = 0.116, 95 %CI = 0.040-0.334, p = 0.000). In children ≤6 years old, boys suffered electrical injuries more frequently than girls; battery powered vehicle (47.53 %) was primarily the cause of injury; most of the patients (64.64 %) were exposed to low voltage below 100 Vs, mainly in the case of adolescent children. CONCLUSION: Male preschoolers accounted for the majority of electrical injury cases, and these accidents mostly happened in household electrical appliances and household battery cars. Overall, it is necessary to improve family electrical safety education and reinforce protective measures against electric injury to children.


Assuntos
Traumatismos por Eletricidade , Hospitalização , Humanos , Masculino , Feminino , Pré-Escolar , Criança , Estudos Retrospectivos , Traumatismos por Eletricidade/epidemiologia , Incidência , Hospitalização/estatística & dados numéricos , Fatores de Risco , Adolescente , Lactente , China/epidemiologia , Acidentes Domésticos/prevenção & controle , Acidentes Domésticos/estatística & dados numéricos , Distribuição por Idade , Distribuição por Sexo , Queimaduras por Corrente Elétrica/epidemiologia , Queimaduras por Corrente Elétrica/prevenção & controle , Estações do Ano , Fontes de Energia Elétrica
19.
J Am Heart Assoc ; 13(7): e033609, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38533936

RESUMO

BACKGROUND: Remote ischemic conditioning has been found to be effective in improving functional outcomes in acute ischemic stroke. We conducted a post hoc analysis of the RICAMIS (Remote Ischemic Conditioning for Acute Moderate Ischemic Stroke) trial to determine whether long-term remote ischemic conditioning duration after stroke onset is associated with better clinical outcomes in ischemic stroke. METHODS AND RESULTS: Patients from the full analysis set were included in this secondary analysis. The primary outcome was the proportion of patients with an excellent functional outcome at 90 days, defined as a modified Rankin Scale score of 0 to 1. Among the 1776 patients, there were 55 patients in the 1 to 7 days remote ischemic conditioning group, 345 in the 8 to 10 days group, 412 in the 11 to 13 days group, 51 in the 14 to 16 days group, and 913 in the control group. Compared with the control group, a significantly higher proportion of excellent functional outcomes at 90 days was found in the 11 to 13 days remote ischemic conditioning group (adjusted absolute difference, 9.1% [95% CI, 3.7%-14.5%]; P =0.001), which was attenuated in the other groups (adjusted absolute difference in the 8-10 days group, 2.0% [95% CI, -4.0% to 8.0%]; P=0.51; adjusted absolute difference in the 14-16 days group, 7.4% [95% CI, -5.8% to 20.5%]; P=0.27), but compared to the control group, there was lower proportion of excellent functional outcomes in the 1 to 7 days group (adjusted absolute difference, -14.4% [95% CI, -27.8% to 0.0%]; P=0.05). CONCLUSIONS: Among patients with acute moderate ischemic stroke, a higher likelihood of excellent clinical outcome was found in patients with longer duration of remote ischemic conditioning.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/terapia , Isquemia Encefálica/complicações , AVC Isquêmico/complicações , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/complicações , Resultado do Tratamento
20.
Int J Biol Macromol ; 263(Pt 1): 130688, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458294

RESUMO

This study reports the rational engineering of the S1' substrate-binding pocket of a thermally-stable keratinase from Pseudomonas aeruginosa 4-3 (4-3Ker) to improve substrate specificity to typical keratinase (K/C > 0.5) and catalytic activity without compromising thermal stability for efficient keratin degradation. Of 10 chosen mutation hotspots in the S1' substrate-binding pocket, the top three mutations M128R, A138V, and V142I showing the best catalytic activity and substrate specificity were identified. Their double and triple combinatorial mutants synergistically overcame limitations of single mutants, fabricating an excellent M128R/A138V/V142I triple mutant which displayed a 1.21-fold increase in keratin catalytic activity, 1.10-fold enhancement in keratin/casein activity ratio, and a 3.13 °C increase in half-inactivation temperature compared to 4-3Ker. Molecular dynamics simulations revealed enhanced flexibility of critical amino acid residues at the substrate access tunnel, improved global protein rigidity, and heightened hydrophobicity within the active site likely underpinned the increased catalytic activity and substrate specificity. Additionally, the triple mutant improved the feather degradation rate by 32.86 % over the wild-type, far exceeding commercial keratinase in substrate specificity and thermal stability. This study exemplified engineering a typical keratinase with enhanced substrate specificity, catalytic activity, and thermal stability from thermally-stable 4-3Ker, providing a more robust tool for feather degradation.


Assuntos
Queratinas , Peptídeo Hidrolases , Queratinas/metabolismo , Especificidade por Substrato , Peptídeo Hidrolases/metabolismo , Temperatura , Concentração de Íons de Hidrogênio
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