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1.
J Virol ; 98(7): e0020224, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38842318

RESUMEN

Nucleoprotein (N) is well known for its function in the encapsidation of the genomic RNAs of negative-strand RNA viruses, which leads to the formation of ribonucleoproteins that serve as templates for viral transcription and replication. However, the function of the N protein in other aspects during viral infection is far from clear. In this study, the N protein of snakehead vesiculovirus (SHVV), a kind of fish rhabdovirus, was proved to be ubiquitinated mainly via K63-linked ubiquitination. We identified nine host E3 ubiquitin ligases that interacted with SHVV N, among which seven E3 ubiquitin ligases facilitated ubiquitination of the N protein. Further investigation revealed that only two E3 ubiquitin ligases, Siah E3 ubiquitin protein ligase 2 (Siah2) and leucine-rich repeat and sterile alpha motif containing 1 (LRSAM1), mediated K63-linked ubiquitination of the N protein. SHVV infection upregulated the expression of Siah2 and LRSAM1, which maintained the stability of SHVV N. Besides, overexpression of Siah2 or LRSAM1 promoted SHVV replication, while knockdown of Siah2 or LRSAM1 inhibited SHVV replication. Deletion of the ligase domain of Siah2 or LRSAM1 did not affect their interactions with SHVV N but reduced the K63-linked ubiquitination of SHVV N and SHVV replication. In summary, Siah2 and LRSAM1 mediate K63-linked ubiquitination of SHVV N to facilitate SHVV replication, which provides novel insights into the role of the N proteins of negative-strand RNA viruses. IMPORTANCE: Ubiquitination of viral protein plays an important role in viral replication. However, the ubiquitination of the nucleoprotein (N) of negative-strand RNA viruses has rarely been investigated. This study aimed at investigating the ubiquitination of the N protein of a fish rhabdovirus SHVV (snakehead vesiculovirus), identifying the related host E3 ubiquitin ligases, and determining the role of SHVV N ubiquitination and host E3 ubiquitin ligases in viral replication. We found that SHVV N was ubiquitinated mainly via K63-linked ubiquitination, which was mediated by host E3 ubiquitin ligases Siah2 (Siah E3 ubiquitin protein ligase 2) and LRSAM1 (leucine-rich repeat and sterile alpha motif containing 1). The data suggested that Siah2 and LRSAM1 were hijacked by SHVV to ubiquitinate the N protein for viral replication, which exhibited novel anti-SHVV targets for drug design.


Asunto(s)
Nucleoproteínas , Ubiquitina-Proteína Ligasas , Ubiquitinación , Vesiculovirus , Replicación Viral , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Animales , Nucleoproteínas/metabolismo , Nucleoproteínas/genética , Vesiculovirus/fisiología , Vesiculovirus/metabolismo , Vesiculovirus/genética , Humanos , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Células HEK293 , Proteínas Virales/metabolismo , Proteínas Virales/genética , Línea Celular , Infecciones por Rhabdoviridae/virología , Infecciones por Rhabdoviridae/metabolismo , Enfermedades de los Peces/virología , Enfermedades de los Peces/metabolismo
2.
Nature ; 572(7769): 341-346, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31367039

RESUMEN

Salinity is detrimental to plant growth, crop production and food security worldwide. Excess salt triggers increases in cytosolic Ca2+ concentration, which activate Ca2+-binding proteins and upregulate the Na+/H+ antiporter in order to remove Na+. Salt-induced increases in Ca2+ have long been thought to be involved in the detection of salt stress, but the molecular components of the sensing machinery remain unknown. Here, using Ca2+-imaging-based forward genetic screens, we isolated the Arabidopsis thaliana mutant monocation-induced [Ca2+]i increases 1 (moca1), and identified MOCA1 as a glucuronosyltransferase for glycosyl inositol phosphorylceramide (GIPC) sphingolipids in the plasma membrane. MOCA1 is required for salt-induced depolarization of the cell-surface potential, Ca2+ spikes and waves, Na+/H+ antiporter activation, and regulation of growth. Na+ binds to GIPCs to gate Ca2+ influx channels. This salt-sensing mechanism might imply that plasma-membrane lipids are involved in adaption to various environmental salt levels, and could be used to improve salt resistance in crops.


Asunto(s)
Arabidopsis/citología , Arabidopsis/metabolismo , Señalización del Calcio , Calcio/metabolismo , Glicoesfingolípidos/metabolismo , Células Vegetales/metabolismo , Cloruro de Sodio/metabolismo , Arabidopsis/genética , Glucuronosiltransferasa/genética , Glucuronosiltransferasa/metabolismo , Potenciales de la Membrana/efectos de los fármacos , Mutación , Estrés Salino/genética , Estrés Salino/fisiología , Cloruro de Sodio/farmacología , Intercambiadores de Sodio-Hidrógeno/metabolismo
3.
Differentiation ; 138: 100789, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38896972

RESUMEN

Osteoclast (OC) differentiation, vital for bone resorption, depends on osteoclast and precursor fusion. Osteoprotegerin (OPG) inhibits osteoclast differentiation. OPG's influence on fusion and mechanisms is unclear. Osteoclasts and precursors were treated with OPG alone or with ATP. OPG significantly reduced OC number, area and motility and ATP mitigated OPG's inhibition. However, OPG hardly affected the motility of precusors. OPG downregulated fusion-related molecules (CD44, CD47, DC-STAMP, ATP6V0D2) in osteoclasts, reducing only CD47 in precursors. OPG reduced Connexin43 phosphorylated forms (P1 and P2) in osteoclasts, affecting only P2 in precursors. OPG disrupted subcellular localization of CD44, CD47, DC-STAMP, ATP6V0D2, and Connexin43 in both cell types. Findings underscore OPG's multifaceted impact, inhibiting multinucleated osteoclast and mononuclear precursor fusion through distinct molecular mechanisms. Notably, ATP mitigates OPG's inhibitory effect, suggesting a potential regulatory role for the ATP signaling pathway. This study enhances understanding of intricate processes in osteoclast differentiation and fusion, offering insights into potential therapeutic targets for abnormal bone metabolism.


Asunto(s)
Adenosina Trifosfato , Diferenciación Celular , Osteoclastos , Osteoprotegerina , Osteoprotegerina/metabolismo , Osteoprotegerina/genética , Osteoclastos/metabolismo , Osteoclastos/citología , Animales , Adenosina Trifosfato/metabolismo , Ratones , Conexina 43/metabolismo , Conexina 43/genética , Fusión Celular , Antígeno CD47/metabolismo , Antígeno CD47/genética , Receptores de Hialuranos/metabolismo , Receptores de Hialuranos/genética , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Resorción Ósea/metabolismo , Resorción Ósea/genética , Resorción Ósea/patología , Transducción de Señal , ATPasas de Translocación de Protón Vacuolares/metabolismo , ATPasas de Translocación de Protón Vacuolares/genética , Proteínas del Tejido Nervioso
4.
J Cell Physiol ; 239(2): e31129, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38192063

RESUMEN

Myelodysplastic syndromes (MDS) are a group of heterogeneous myeloid clonal disorders characterized by ineffective hematopoiesis. Accumulating evidence has shown that macrophages (MΦs) are important components in the regulation of tumor progression and hematopoietic stem cells (HSCs). However, the roles of bone marrow (BM) MΦs in regulating normal and malignant hematopoiesis in different clinical stages of MDS are largely unknown. Age-paired patients with lower-risk MDS (N = 15), higher-risk MDS (N = 15), de novo acute myeloid leukemia (AML) (N = 15), and healthy donors (HDs) (N = 15) were enrolled. Flow cytometry analysis showed increased pro-inflammatory monocyte subsets and a decreased classically activated (M1) MΦs/alternatively activated (M2) MΦs ratio in the BM of patients with higher-risk MDS compared to lower-risk MDS. BM MФs from patients with higher-risk MDS and AML showed impaired phagocytosis activity but increased migration compared with lower-risk MDS group. AML BM MΦs showed markedly higher S100A8/A9 levels than lower-risk MDS BM MΦs. More importantly, coculture experiments suggested that the HSC supporting abilities of BM MΦs from patients with higher-risk MDS decreased, whereas the malignant cell supporting abilities increased compared with lower-risk MDS. Gene Ontology enrichment comparing BM MΦs from lower-risk MDS and higher-risk MDS for genes was involved in hematopoiesis- and immunity-related pathways. Our results suggest that BM MΦs are involved in ineffective hematopoiesis in patients with MDS, which indicates that repairing aberrant BM MΦs may represent a promising therapeutic approach for patients with MDS.


Asunto(s)
Infecciones , Macrófagos , Síndromes Mielodisplásicos , Humanos , Médula Ósea/patología , Hematopoyesis , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Macrófagos/patología , Síndromes Mielodisplásicos/genética , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Infecciones/patología
5.
Clin Immunol ; 261: 109929, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38331303

RESUMEN

Previous studies have shown that epigenetic factors are involved in the occurrence and development of rheumatoid arthritis (RA). However, the role of N6-methyladenosine (m6A) methylation in RA has not been determined. The aim of this study was to investigate the role and regulatory mechanisms of hypoxia-induced expression of the m6A demethylase alkB homolog 5 (ALKBH5) in RA fibroblast-like synoviocytes (FLSs). Synovial tissues were collected from RA and osteoarthritis (OA) patients, and RA FLSs were obtained. ALKBH5 expression in RA FLSs and collagen-induced arthritis (CIA) model rats was determined using quantitative reverse transcription-PCR (qRT-PCR), western blotting and immunohistochemistry (IHC). Using ALKBH5 overexpression and knockdown, we determined the role of ALKBH5 in RA FLS aggression and inflammation. The role of ALKBH5 in RA FLS regulation was explored using m6A-methylated RNA sequencing and methylated RNA immunoprecipitation coupled with quantitative real-time PCR. The expression of ALKBH5 was increased in RA synovial tissues, CIA model rats and RA FLSs, and a hypoxic environment increased the expression of ALKBH5 in FLSs. Increased expression of ALKBH5 promoted the proliferation and migration of RA-FLSs and inflammation. Conversely, decreased ALKBH5 expression inhibited the migration of RA-FLSs and inflammation. Mechanistically, hypoxia-induced ALKBH5 expression promoted FLS aggression and inflammation by regulating CH25H mRNA stability. Our study elucidated the functional roles of ALKBH5 and mRNA m6A methylation in RA and revealed that the HIF1α/2α-ALKBH5-CH25H pathway may be key for FLS aggression and inflammation. This study provides a novel approach for the treatment of RA by targeting the HIF1α/2α-ALKBH5-CH25H pathway.


Asunto(s)
Adenina/análogos & derivados , Agresión , Artritis Reumatoide , Humanos , Ratas , Animales , Artritis Reumatoide/genética , Artritis Reumatoide/metabolismo , Inflamación/metabolismo , Hipoxia , Fibroblastos/metabolismo , Proliferación Celular , Células Cultivadas , Desmetilasa de ARN, Homólogo 5 de AlkB/genética , Desmetilasa de ARN, Homólogo 5 de AlkB/metabolismo
6.
Mol Carcinog ; 63(7): 1362-1377, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38656551

RESUMEN

Acetyl-CoAacyltransferase2 (ACAA2) is a key enzyme in the fatty acid oxidation pathway that catalyzes the final step of mitochondrial ß oxidation, which plays an important role in fatty acid metabolism. The expression of ACAA2 is closely related to the occurrence and malignant progression of tumors. However, the function of ACAA2 in ovarian cancer is unclear. The expression level and prognostic value of ACAA2 were analyzed by databases. Gain and loss of function were carried out to explore the function of ACAA2 in ovarian cancer. RNA-seq and bioinformatics methods were applied to illustrate the regulatory mechanism of ACAA2. ACAA2 overexpression promoted the growth, proliferation, migration, and invasion of ovarian cancer, and ACAA2 knockdown inhibited the malignant progression of ovarian cancer as well as the ability of subcutaneous tumor formation in nude mice. At the same time, we found that OGT can induce glycosylation modification of ACAA2 and regulate the karyoplasmic distribution of ACAA2. OGT plays a vital role in ovarian cancer as a function of oncogenes. In addition, through RNA-seq sequencing, we found that ACAA2 regulates the expression of DIXDC1. ACAA2 regulated the malignant progression of ovarian cancer through the WNT/ß-Catenin signaling pathway probably. ACAA2 is an oncogene in ovarian cancer and has the potential to be a target for ovarian cancer therapy.


Asunto(s)
Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Ratones Desnudos , Neoplasias Ováricas , Femenino , Humanos , Neoplasias Ováricas/patología , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Animales , Ratones , Línea Celular Tumoral , Movimiento Celular , Vía de Señalización Wnt , Pronóstico , Carcinogénesis/genética
7.
Ann Hematol ; 103(4): 1293-1303, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38148345

RESUMEN

Diallyl disulfide (DADS), one of the main components of garlic, is well known to have anticancer effects on multiple cancers. However, its efficacy in treating multiple myeloma (MM) is yet to be determined. We explored the effects of DADS on MM cells and investigated the synergistic effects of DADS when combined with five anti-MM drugs, including melphalan, bortezomib, carfilzomib, doxorubicin, and lenalidomide. We analyzed cell viability, cell apoptosis, and DNA damage to determine the efficacy of DADS and the drug combinations. Our findings revealed that DADS induces apoptosis in MM cells through the mitochondria-dependent pathway and increases the levels of γ-H2AX, a DNA damage marker. Combination index (CI) measurements indicated that the combination of DADS with melphalan has a significant synergistic effect on MM cells. This was further confirmed by the increases in apoptotic cells and DNA damage in MM cells treated with the two drug combinations compared with those cells treated with a single drug alone. The synergy between DADS and melphalan was also observed in primary MM cells. Furthermore, mechanistic investigations showed that DADS decreases reduced glutathione (GSH) levels and increases reactive oxygen species (ROS) production in MM cells. The addition of GSH is effective in neutralizing DADS cytotoxicity and inhibiting the synergy between DADS and melphalan in MM cells. Taken together, our study highlights the effectiveness of DADS in treating MM cells and the promising therapeutic potential of combining DADS and melphalan for MM treatment.


Asunto(s)
Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-disulfónico/análogos & derivados , Compuestos Alílicos , Disulfuros , Melfalán , Mieloma Múltiple , Humanos , Especies Reactivas de Oxígeno , Melfalán/farmacología , Mieloma Múltiple/tratamiento farmacológico , Daño del ADN , Apoptosis , Combinación de Medicamentos
8.
Ann Hematol ; 103(9): 3627-3637, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38647678

RESUMEN

Iron contributes to tumor initiation and progression; however, excessive intracellular free Fe2+ can be toxic to cancer cells. Our findings confirmed that multiple myeloma (MM) cells exhibited elevated intracellular iron levels and increased ferritin, a key protein for iron storage, compared with normal cells. Interestingly, Bortezomib (BTZ) was found to trigger ferritin degradation, increase free intracellular Fe2+, and promote ferroptosis in MM cells. Subsequent mechanistic investigation revealed that BTZ effectively increased NCOA4 levels by preventing proteasomal degradation in MM cells. When we knocked down NCOA4 or blocked autophagy using chloroquine, BTZ-induced ferritin degradation and the increase in intracellular free Fe2+ were significantly reduced in MM cells, confirming the role of BTZ in enhancing ferritinophagy. Furthermore, the combination of BTZ with RSL-3, a specific inhibitor of GPX4 and inducer of ferroptosis, synergistically promoted ferroptosis in MM cell lines and increased cell death in both MM cell lines and primary MM cells. The induction of ferroptosis inhibitor liproxstatin-1 successfully counteracted the synergistic effect of BTZ and RSL-3 in MM cells. Altogether, our findings reveal that BTZ elevates intracellular free Fe2+ by enhancing NCOA4-mediated ferritinophagy and synergizes with RSL-3 by increasing ferroptosisin MM cells.


Asunto(s)
Bortezomib , Sinergismo Farmacológico , Ferritinas , Ferroptosis , Hierro , Mieloma Múltiple , Coactivadores de Receptor Nuclear , Humanos , Mieloma Múltiple/metabolismo , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/patología , Coactivadores de Receptor Nuclear/metabolismo , Coactivadores de Receptor Nuclear/genética , Bortezomib/farmacología , Ferritinas/metabolismo , Ferroptosis/efectos de los fármacos , Hierro/metabolismo , Línea Celular Tumoral , Autofagia/efectos de los fármacos , Antineoplásicos/farmacología , Carbolinas
9.
Environ Sci Technol ; 58(35): 15381-15394, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39136294

RESUMEN

China is confronting the dual challenges of air pollution and climate change, mandating the co-control of air pollutants and CO2 emissions from their shared sources. Here we identify key sources for co-control that prioritize the mitigation of PM2.5-related health burdens, given the homogeneous impacts of CO2 emissions from various sources. By applying an integrated analysis framework that consists of a detailed emission inventory, a chemical transport model, a multisource fused dataset, and epidemiological concentration-response functions, we systematically evaluate the contribution of emissions from 390 sources (30 provinces and 13 socioeconomic sectors) to PM2.5-related health impacts and CO2 emissions, as well as the marginal health benefits of CO2 abatement across China. The estimated source-specific contributions exhibit substantial disparities, with the marginal benefits varying by 3 orders of magnitude. The rural residential, transportation, metal, and power and heating sectors emerge as pivotal sources for co-control, with regard to their relatively large marginal benefits or the sectoral total benefits. In addition, populous and heavily industrialized provinces such as Shandong and Henan are identified as the key regions for co-control. Our study highlights the significance of incorporating health benefits into formulating air pollution and carbon co-control strategies for improving the overall social welfare.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Dióxido de Carbono , China , Dióxido de Carbono/análisis , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Cambio Climático , Monitoreo del Ambiente
10.
Artículo en Inglés | MEDLINE | ID: mdl-39292262

RESUMEN

Accelerated repetitive transcranial magnetic stimulation (rTMS) is a promising treatment for treatment-resistant depression (TRD). We aimed to investigate the existence of clinical predictive factors in response to accelerated rTMS in the treatment of TRD. In total, 119 TRD patients who received accelerated rTMS were included in this study. The stimulation protocol was 15 Hz stimulation over the the left dorsolateral prefrontal cortex. The protocol consisted of 25 sessions, each session lasting 30 min for a total of 3000 pulses. Five sessions were applied per day for 5 consecutive days. At baseline (T0), day 5 (immediately after treatment) (T1), 4 weeks after treatment (T2), depression severity was evaluated using the 17-item Hamilton Depression Rating Scale (HAMD-17), cognitive function was evaluated using Wisconsin Card Sorting Test (WCST), the intensity of suicidal ideation was evaluated using the Columbia-Suicide Severity Rating Scale (C-SSRS). Systemic immune-inflammation index (SII) was calculated at T0 and T2. The HAMD-17 scores, WCST performance, the C-SSRS scores at T1 and T2 were improved from T0 (P < 0.01). The SII at T2 was lower than at T0 (P < 0.01). The response rates at T1 and T2 were 57.98% (69/119) and 48.74% (58/119), respectively. The results of binary logistic analysis showed that shorter course of depression, two failed antidepressant trials, no history of ECT treatment, and lower levels of SII were predictive factors for accelerated rTMS treatment response at T1 and T2 (P < 0.05), while not having a history of hospitalization was a predictive factor for response at T2 (P < 0.05) but not at T1 (P > 0.05). Based on ROC curve analysis, the optimal cut-off values of SII for discriminating responders from non-responders at T1 and T2 were < 478.56 and < 485.03, respectively. The AUC of SII at T0 predicting response for T1 and T2 were 0.729 and 0.797. We found several clinical predictors of better responses to the accelerated rTMS. Identifying clinical predictors of response is relevant to personalize and adapt rTMS protocols in TRD patients.

11.
Clin Lab ; 70(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38623678

RESUMEN

BACKGROUND: The goal was to develop a risk assessment model for predicting red blood cell (RBC) transfusion in neonatal patients to assist hospital blood supply departments in providing small portions of RBCs to those requiring RBC transfusion on time. METHODS: Clinical information was collected from 1,201 children admitted to the neonatal unit. Clinical factors associated with predicting RBC transfusion were screened, and prediction models were developed using stepwise and multifactorial logistic regression analyses, followed by the evaluation of prediction models using receiver operating characteristic curves, calibration curves, and decision curve analysis (DCA). RESULTS: Overall, 81 neonatal patients were transfused with RBCs, and the variables of gestational age at birth, age < 1 month, receipt of mechanical ventilation, and infant anemia were included in the final prediction model. The area under the curve of the prediction model was 0.936 (0.921 - 0.949), which was significantly higher than that of the individual indicators of gestational age at birth, age at admission < 1 month, receipt of mechanical ventilation, and infant anemia (p < 0.001). DCA showed a standardized net benefit for the possible risk of infant RBC transfusion at 0.1 - 1.0. CONCLUSIONS: We developed a risk assessment model to predict the risk of RBC transfusion in neonatal patients that can effectively assess the risk of RBC transfusion in children.


Asunto(s)
Anemia , Transfusión de Eritrocitos , Recién Nacido , Lactante , Niño , Humanos , Transfusión de Eritrocitos/efectos adversos , Anemia/diagnóstico , Anemia/terapia , Edad Gestacional , Eritrocitos , Medición de Riesgo
12.
Neurol Sci ; 2024 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-39466326

RESUMEN

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disease characterized by motor paralysis, tremor,and cognitive impairment. Risk factors such as brain hypoxia caused by aging and abnormal expression of HIF-1α areconsidered to be key to the development of PD, including α-synuclein accumulation and ferroptosis. However, therelationship between HIF-1α signaling and ferroptosis in PD has not been elucidated. The stable expression of HIF-1αinhibits the pathological development of PD. Aging aggravates PD pathology by promoting α-synuclein accumulationand oxidative stress. METHODS: The literature on lipid peroxidation, oxidative stress, iron metabolism and other key factors in Parkinson'sdisease in recent years was reviewed through a variety of literature search channels, such as PubMed and Elsevier. RESULTS: HIF-1α mediated ferroptosis through oxidative stress and GPX4-GSH system. HIF-1α mediates ferroptosisthrough Keap1-Nrf2-ARE, Grx3 and Grx4. HIF-1α mediates ferroptosis through iron metabolism. CONCLUSION: This article reviews the oxygen-dependent regulatory mechanism of HIF-1α and its role in cerebralhypoxia homeostasis. Studies in the past decade have shown that Hif-1α mediated ferroptosis is important in PD.HIF-1α has a dual role, depending on the degree of cellular hypoxia and the environment. The equilibrium complexityneeds to be explained, and the role of ferroptosis needs to be investigated. The literature shows that the stabilizationof HIF-1α with PHD inhibitors and the combination of antioxidants and iron chelators are potential therapeuticdirections. In the future, the optimal use time and dose of inhibitors should be studied to improve the efficacy.

13.
Appl Opt ; 63(16): 4435-4440, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38856624

RESUMEN

The integration of silicon waveguides with low-dimensional materials with excellent optoelectronic properties can enable compact and highly integrated optical devices with multiple advantages for multiple fields. A carbon nanotube (CNT) photodetector integrated on the silicon waveguide has the potential to meet on-chip high-speed optical interconnection systems, based on the outstanding properties of CNTs such as picosecond-level intrinsic photoresponse time, high charge carrier mobility, broad spectral response, high absorption coefficient, and so on. However, the thermal stability of the device may be compromised due to the local suspension in the channel for the height difference between the WG and the substrate. Here, we report a low-cost and low-optical-loss method to achieve the planarized silicon waveguide. After that, the CNT photodetectors integrated on the original and planarized waveguide with asymmetric palladium (Pd)-hafnium (Hf) metal contacts are fabricated. The influence of this planarization method on the performance of devices is analyzed via comparing the dark leakage current, the leakage current rectification ratio (CRR), the series resistances (R S), and the photoelectric response. Finally, a CNT photodetector based on the planarized waveguide with a photocurrent (I p h ) ∼510.84n A, a photoresponsivity (R I) ∼51.04m A/W, the dark current ∼0.389µA, as well as a 3 dB bandwidth ∼34G H z at the large reverse voltage -3V is shown.

14.
BMC Public Health ; 24(1): 531, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38378524

RESUMEN

BACKGROUND: In the global trend of actively promoting the participation of older adults in the digital age, the relevant negative issues featuring potential Internet Addiction (IA) among them has risen to be a new challenge facing the global public health. However, there is a severe lack of related research. This study aimed to gain a comprehensive understanding of the phenomenon and process of IA among the elderly. The purpose of this paper is to introduce factors that may influence IA in the demographic. METHODS: This study employed qualitative descriptive research methods to investigate older adults' perceptions and experiences of IA. Semi-structured in-depth personal interviews were conducted between March and June 2023 with 36 senior citizens from urban communities in Chongqing, Southwest China. Data were analyzed via inductive content analysis methods. RESULTS: Through data analysis, 2 main categories concerning IA in older adults were identified: risk factors and protective factors. The risk factor categories include 5 individual factors (e.g., Internet as the major avenue for pursuing personal hobbies and interests, etc.), 3 family factors (e.g., household WIFI increasing the risk of prolonged Internet use indoors, etc.), 2 peer factors (e.g., peer recommendation and guidance as catalysts for intensified Internet engagement, etc.), 2 socio-environmental factors (e.g., the widespread daily Internet use spurs offline intolerance, etc.), and 3 Internet platform factors (e.g., the plenitude of online content triggers endless viewing/browsing behaviors, etc.). The category of protective factors encompasses 2 individual factors (e.g., a higher level of perceived risk regarding internet health hazards, etc.) and 2 family factors (e.g., more family commitment, etc.). CONCLUSIONS: Older adults' Internet addictive behaviors are shaped by multiple and complex internal and external factors. A higher level of online health risk perception is a key protective factor to effectively avoid the occurrence and deterioration of IA among the aged, a distinct finding from this study. It is believed that the "individual-family-peer-community" synergy strategy is expected to become an essential direction for IA intervention for older adults, in order to promote healthy Internet use among older adults.


Asunto(s)
Conducta Adictiva , Trastorno de Adicción a Internet , Humanos , Anciano , China/epidemiología , Proyectos de Investigación , Grupo Paritario , Internet , Conducta Adictiva/epidemiología
15.
Ecotoxicol Environ Saf ; 278: 116404, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38705038

RESUMEN

Manganese (Mn) is an essential trace element for maintaining bodily functions. Excessive exposure to Mn can pose serious health risks to humans and animals, particularly to the nervous system. While Mn has been implicated as a neurotoxin, the exact mechanism of its toxicity remains unclear. Ferroptosis is a form of programmed cell death that results from iron-dependent lipid peroxidation. It plays a role in various physiological and pathological cellular processes and may be closely related to Mn-induced neurotoxicity. However, the mechanism of ferroptosis in Mn-induced neurotoxicity has not been thoroughly investigated. Therefore, this study aims to investigate the role and mechanism of ferroptosis in Mn-induced neurotoxicity. Using bioinformatics, we identified significant changes in genes associated with ferroptosis in Mn-exposed animal and cellular models. We then evaluated the role of ferroptosis in Mn-induced neurotoxicity at both the animal and cellular levels. Our findings suggest that Mn exposure causes weight loss and nervous system damage in mice. In vitro and in vivo experiments have shown that exposure to Mn increases malondialdehyde, reactive oxygen species, and ferrous iron, while decreasing glutathione and adenosine triphosphate. These findings suggest that Mn exposure leads to a significant increase in lipid peroxidation and disrupts iron metabolism, resulting in oxidative stress injury and ferroptosis. Furthermore, we assessed the expression levels of proteins and mRNAs related to ferroptosis, confirming its significant involvement in Mn-induced neurotoxicity.


Asunto(s)
Ferroptosis , Sobrecarga de Hierro , Peroxidación de Lípido , Manganeso , Oxidación-Reducción , Ferroptosis/efectos de los fármacos , Animales , Manganeso/toxicidad , Ratones , Peroxidación de Lípido/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Síndromes de Neurotoxicidad/patología , Masculino , Hierro/toxicidad , Hierro/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Humanos
16.
Ecotoxicol Environ Saf ; 286: 117216, 2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-39437518

RESUMEN

Cadmium (Cd) has adverse effects on organisms. Serine is an essential nutritional factor and its nutritional value is extremely high for body. To explore the effects of serine on spleen toxicity induced by Cd in mice, cadmium chloride (CdCl2, 50 mg/L) and serine (50 g/L) were individually administered or co-administrated in drinking water of mice for 18 weeks. Results demonstrated that Cd exposure induced splenic toxicity and serine against the toxicity damage caused by Cd in mice. Under Cd stress, trace element homeostasis was disturbed, the mice's body weight and spleen index were increased, and splenic morphology and ultrastructure were altered. Furthermore, Cd exposure led to the cell populations disorder, which in turn triggers cell death. Notably, Cd treatment induced oxidative stress and inflammation, increased M1/M2 (iNOS, CD68) and Th1/Th2 (T-bet, CD4) levels, decreased M1/M2 (Arg1) and Th1/Th2 (GATA3) levels, while disrupted the macrophages and lymphocytes homeostasis, which trigged apoptosis and pyroptosis in spleen. In contrast, serine supplementation changed the levels of Cd and other elements, weakened Cd-induced tissue damage and inflammation, enhanced antioxidant capacity, significantly restored cell homeostasis, and effectively inhibited Cd-induced apoptosis and pyroptosis in the spleen. Shortly, the results verified that serine had an ameliorating toxicity effect and restored the M1/M2 and Th1/Th2 balance, restrained apoptosis and pyroptosis induced by Cd.

17.
J Environ Manage ; 353: 120142, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38306855

RESUMEN

The effective removal of heavy metal ions from sewage remains a critical issue, and applying the operability of magnetic materials to large volume wastewater treatment has been a significant challenge. In this paper, metal ions adsorption induced aggregation strategy is proposed to solve this contradiction. The intelligent magnetic fluid designed in this study is a well-dispersed fluid state when treating sewage, and can efficiently adsorb heavy metal ions in wastewater with high adsorption capacity and ultra-fast adsorption kinetics. More importantly, after saturation of adsorption, the magnetic fluid will transform from a well-dispersed fluid state to an agglomeration state which is easy to precipitate and separate via external magnetic field. In a simple and effective way, the particles size of magnetic nanoparticles was precisely controlled by cellulose derivatives modification to obtain a stable magnetic fluid in water. The Freundlich model best described Cu2+ adsorption on magnetite nanoparticles, the correlation coefficients from the Cu2+ adsorption on the two magnetic fluids are 0.9554 and 0.9336, n are 1.868 and 2.117, revealing a favorable adsorption of Cu2+ onto magnetic fluids. The pseudo second-order model fitted the adsorption kinetic data better, the qe are 0.1948 and 0.1315 mmol/g and the R2 are 0.9999, indicating that the adsorption of Cu2+ onto the magnetic fluid was dominated by chemisorption. Moreover, the removal rate of Cu2+ in tap water and lake water was more than 97.1%, and the removal rate of large volume sewage was 81.7%. The synthetic magnetic fluid has high adsorption capacity, ultra-fast adsorption kinetics, reusability and easy separation, indicating its potential application for the removal of heavy metal ions from large-volume sewage.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Cobre/análisis , Aguas del Alcantarillado , Adsorción , Iones , Agua , Fenómenos Magnéticos , Cinética , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno
18.
Environ Geochem Health ; 46(3): 75, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38367077

RESUMEN

Asthma is a common chronic heterogeneous disease. Outdoor air pollutants are an important cause of acute asthma. Until now, the association between the risk of acute asthma and outdoor air pollutants is unclear. And the relationship between the different phenotypes of asthma and outdoor air pollutants has not been reported. Thus, an analysis of the association between outdoor air pollutants and daily acute asthma inpatient and outpatient visits in Xi'an, China, from January 1 to December 31, 2018, was conducted. A total of 3395 people were included in the study. The statistical analysis and relational analysis based on the logistic regression were used for illustrating the relatedness of the acute asthma risk factor and phenotype with outdoor air pollutants, while the age, gender, pollen peak and non-pollen peak periods, high type 2 (T2) asthma and non-high T2 asthma were also stratified. Results showed that particulate matter with particle size below 10 µm and 2.5 µm (PM10 and PM2.5), sulfur dioxide(SO2), nitrogen dioxide(NO2), and carbon monoxide(CO) increase the risk of acute asthma and that air pollutants have a lagged effect on asthma patients. PM10, NO2, CO, and Ozone (O3) are associated with an increased risk of acute attacks of high T2 asthma. PM10, PM2.5, SO2, NO2 and CO are associated with an increased risk of acute asthma in males of 0-16 years old. PM10 and PM2.5 are more harmful to asthma patients with abnormal lung function.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Asma , Masculino , Humanos , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Dióxido de Nitrógeno/toxicidad , Dióxido de Nitrógeno/análisis , Material Particulado/toxicidad , Material Particulado/análisis , Asma/inducido químicamente , Asma/epidemiología , Factores de Riesgo , China/epidemiología
19.
Angew Chem Int Ed Engl ; : e202413657, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39187433

RESUMEN

Regulating the catalytic reaction pathway to essentially break the activity/stability trade-off that limits RuO2 and thus achieves exceptional stability and activity for the acidic oxygen evolution reaction (OER) is important yet challenging. Herein, we propose a novel strategy of incorporating atomically dispersed V species, including O-bridged V dimers and V single atoms, into RuO2 lattices to trigger direct O-O radical coupling to release O2 without the generation of *OOH intermediates. Vn-RuO2 showed high activity with a low overpotential of 227 mV at 10 mA cm-2 and outstanding stability during a 1050 h test in acidic electrolyte. Operando spectroscopic studies and theoretical calculations revealed that compared with the V single atom-doping case, the introduction of the V dimer into RuO2 further decreases the Ru-V atomic distance and weakens the adsorption strength of the *O intermediate to the active V site, which supports the more energetically favorable oxygen radical coupling mechanism (OCM). Furthermore, the highly asymmetric Ru-O-V local structure stabilizes the surface Ru active center by lowering the valence state and increasing the resistance against overoxidation, which result in outstanding stability. This study provides insight into ways of increasing the intrinsic catalytic activity and stability of RuO2 by atomically dispersed species modification.

20.
J Am Chem Soc ; 145(24): 13038-13047, 2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37285479

RESUMEN

The design of active and low-cost electrocatalyst for hydrogen evolution reaction (HER) is the key to achieving a clean hydrogen energy infrastructure. The most successful design principle of hydrogen electrocatalyst is the activity volcano plot, which is based on Sabatier principle and has been used to understand the exceptional activity of noble metal and design of metal alloy catalysts. However, this application of volcano plot in designing single-atom electrocatalysts (SAEs) on nitrogen doped graphene (TM/N4C catalysts) for HER has been less successful due to the nonmetallic nature of the single metal atom site. Herein, by performing ab initio molecular dynamics simulations and free energy calculations on a series of SAEs systems (TM/N4C with TM = 3d, 4d, or 5d metals), we find that the strong charge-dipole interaction between the negatively charged *H intermediate and the interfacial H2O molecules could alter the transition path of the acidic Volmer reaction and dramatically raise its kinetic barrier, despite its favorable adsorption free energy. Such kinetic hindrance is also experimentally confirmed by electrochemical measurements. By combining the hydrogen adsorption free energy and the physics of competing interfacial interactions, we propose a unifying design principle for engineering the SAEs used for hydrogen energy conversion, which incorporates both thermodynamic and kinetic considerations and allows going beyond the activity volcano model.

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