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1.
Nature ; 581(7807): 204-208, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32405000

RESUMEN

It has been speculated that brain activities might directly control adaptive immune responses in lymphoid organs, although there is little evidence for this. Here we show that splenic denervation in mice specifically compromises the formation of plasma cells during a T cell-dependent but not T cell-independent immune response. Splenic nerve activity enhances plasma cell production in a manner that requires B-cell responsiveness to acetylcholine mediated by the α9 nicotinic receptor, and T cells that express choline acetyl transferase1,2 probably act as a relay between the noradrenergic nerve and acetylcholine-responding B cells. We show that neurons in the central nucleus of the amygdala (CeA) and the paraventricular nucleus (PVN) that express corticotropin-releasing hormone (CRH) are connected to the splenic nerve; ablation or pharmacogenetic inhibition of these neurons reduces plasma cell formation, whereas pharmacogenetic activation of these neurons increases plasma cell abundance after immunization. In a newly developed behaviour regimen, mice are made to stand on an elevated platform, leading to activation of CeA and PVN CRH neurons and increased plasma cell formation. In immunized mice, the elevated platform regimen induces an increase in antigen-specific IgG antibodies in a manner that depends on CRH neurons in the CeA and PVN, an intact splenic nerve, and B cell expression of the α9 acetylcholine receptor. By identifying a specific brain-spleen neural connection that autonomically enhances humoral responses and demonstrating immune stimulation by a bodily behaviour, our study reveals brain control of adaptive immunity and suggests the possibility to enhance immunocompetency by behavioural intervention.


Asunto(s)
Conducta Animal/fisiología , Encéfalo/fisiología , Inmunidad Humoral/inmunología , Bazo/inmunología , Bazo/inervación , Acetilcolina/metabolismo , Acetilcolina/farmacología , Neuronas Adrenérgicas/metabolismo , Amígdala del Cerebelo/citología , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/metabolismo , Animales , Encéfalo/citología , Encéfalo/efectos de los fármacos , Colina O-Acetiltransferasa/metabolismo , Hormona Liberadora de Corticotropina/metabolismo , Hemocianinas/inmunología , Inmunoglobulina G/inmunología , Activación de Linfocitos , Masculino , Ratones , Núcleo Hipotalámico Paraventricular/citología , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/metabolismo , Células Plasmáticas/citología , Células Plasmáticas/efectos de los fármacos , Células Plasmáticas/inmunología , Receptores Nicotínicos/deficiencia , Receptores Nicotínicos/metabolismo , Bazo/citología , Bazo/efectos de los fármacos , Estrés Psicológico/inmunología , Estrés Psicológico/metabolismo , Linfocitos T/inmunología
2.
Artículo en Inglés | MEDLINE | ID: mdl-38458373

RESUMEN

OBJECTIVE: To assess contemporaneous and temporal dynamics of perceived social isolation (PSI), secondary conditions, and daily activity patterns in individuals post-stroke. DESIGN: Longitudinal observational study using ecological momentary assessment (EMA) as a real-time assessment of an individual's lived experiences. We conducted dynamic network analyses to examine longitudinal associations among EMA variables. SETTINGS: Home and Community. PARTICIPANTS: 202 individuals with mild-to-moderate chronic stroke (median age=60 years; 45% women; 44% black; 90% ischemic stroke; median NIHSS score=2; N=202). INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: EMA questions measured PSI, secondary conditions (pain, tiredness, stress, anxiety, worthlessness, difficulty concentrating, and cheerfulness), and daily activity patterns (being at home, being alone, and participating in productive activities). RESULTS: The median EMA response rate was 84%. The contemporaneous model showed that PSI was associated with being home, alone, and all symptoms except pain. The temporal model revealed a pathway indicating that feelings of worthlessness predicted PSI (regression coefficient=0.06, P=.019), followed by stress (regression coefficient=0.06, P=.024), and then by being not at home (regression coefficient=-0.04, P=.013). CONCLUSION: Implementing dynamic network analyses on EMA data can uncover dynamic connections among PSI, secondary conditions, and daily activity patterns after stroke. This study found a significant temporal association between PSI and negative emotions. Feeling isolated was followed by feeling stressed, which was followed by a tendency to be out of home, indicating adaptive behaviors in individuals with stroke. These findings highlight the importance of engaging in out-of-home or outdoor activities to mitigate PSI and negative emotions.

3.
Int J Mol Sci ; 25(7)2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38612720

RESUMEN

Safety is fundamental for the practical development and application of energetic materials. Three tricyclic energetic compounds, namely, 1,3-di(1H-tetrazol-5-yl)-1H-1,2,4-triazol-5-amine (ATDT), 5'-nitro-3-(1H-tetrazol-5-yl)-2'H-[1,3'-bi(1,2,4-triazol)]-5-amine (ATNT), and 1-(3,4-dinitro-1H-pyrazol-5-yl)-3-(1H-tetrazol-5-yl)-1H-1,2,4-triazol-5-amine (ATDNP), were effectively synthesized through a simple two-step synthetic route. The introduction of intramolecular hydrogen bonds resulted in excellent molecular planarity for the three new compounds. Additionally, they exhibit regular crystal packing, leading to numerous intermolecular hydrogen bonds and π-π interactions. Benefiting from planar tricyclic structural features, ATDT, ATNT, and ATDNP are insensitive (IS > 60 J, FS = 360 N) when exposed to external stimuli. Furthermore, ATNT (Td = 361.1 °C) and ATDNP (Td = 317.0 °C) exhibit high decomposition temperatures and satisfying detonation performance. The intermolecular hydrogen bonding that produced this planar tricyclic molecular structure serves as a model for the creation of innovative multiple heterocycle energetic materials with excellent stability.


Asunto(s)
Aminas , Vendajes , Enlace de Hidrógeno , Hidrógeno
4.
Cancer Immunol Immunother ; 72(12): 4179-4194, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37831145

RESUMEN

CD47 is highly expressed in many tumor tissues and induces immune evasion by interaction with SIRP-alpha (signal regulatory protein-alpha) expressed on tumor-associated macrophages. In this study, we identified a novel CD47-blocking peptide VK17 by phage display technique. A pro-apoptotic VK30 peptide was obtained after VK17 was fused to KLA amino acid repeat at C-termini. The VK30 was specifically bound to CD47 on lung cancer cells, and subsequently inducing lung cancer cell apoptosis. Meanwhile, the expression of Bax was increased, whereas the expression of Bcl-2 and Ki-67 were reduced in the VK30-treated lung cancer cells. In addition, VK30 effectively improved the phagocytic activity of macrophages against VK30-pretreated lung cancer cells. Combinational treatment of lung cancer cells with blocking antibody anti-CD47 and VK30 additively enhanced VK30 binding to CD47, subsequently increasing lung cancer cell apoptosis and macrophage phagocytosis. Intraperitoneal administration of 2 mg/kg VK30 induced effective trafficking of VK30 into tumor tissues, and suppressing lung cancer cell growth in mice, associated with increased tumor cell apoptosis, macrophage activation and phagocytosis in vivo. The expression of CD47 was reduced in the VK30-treated tumor tissues and the expression level was positively correlated to tumor size. In addition, VK30 reduced the infiltration of CD11b+Ly6G+ neutrophils and CD11b+Ly6C+Ly6G+ granulocytic myeloid-derived suppressor cells (Gr-MDSCs) in tumor tissues, associated with suppressed expression of tumorigenic IL-6 and TNF-alpha from these cell types. Thereby, VK30 exerted anti-tumor effects in mice through inducing tumor cell apoptosis and macrophage phagocytosis. VK30 would be a novel therapeutic peptide in lung cancer immunotherapy.


Asunto(s)
Neoplasias Pulmonares , Ratones , Animales , Neoplasias Pulmonares/patología , Antígeno CD47 , Fagocitosis , Macrófagos , Péptidos/metabolismo
5.
BMC Neurol ; 23(1): 196, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37208623

RESUMEN

BACKGROUND: Patients with myasthenia gravis(MG)often experience multiple symptoms concurrently, which can have an adverse effect on their quality of life(QOL). However, a specific, systemic and reliable scale for symptom clusters in MG is lacking. AIMS: To develop reliable assessment scale for symptom clusters in patients with MG. DESIGN: A cross-sectional descriptive study. METHODS: Based on the unpleasant symptom theory(TOUS), the first draft of the scale was developed through review literature, qualitative interview, and Delphi expert correspondence, the items of the scale were presented and adjusted through cognitive interviews with 12 patients. To conveniently assess the validity and reliability of the scale, a cross-sectional survey was conducted in 283 patients with MG who were recruited from Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, from June to September 2021. RESULTS: The final symptom cluster scale for patients with MG consisted of 19 items(MGSC-19), with a content validity index ranging from 0.828 to 1.000 for each item and the content validity index was 0.980. Four common variables (ocular muscle weakness, general muscular weakness, treatment-related side effects, and psychiatric problems) were identified by exploratory factor analysis, which explained 70.187% of the total variance. The correlation coefficients between the scale dimension and the overall score ranged from 0.395 to 0.769 (all P < 0.01), while the correlation coefficients between dimensions varied from 0.324 to 0.510 (all P < 0.01). The Cronbach's alpha, retest reliability, and half reliability were 0.932, 0.845, and 0.837, respectively. CONCLUSION: The validity and reliability of MGSC-19 were generally good. This scale can be employed to identify the symptom clusters to help healthcare givers develop individualized symptom management measures for patients with MG.


Asunto(s)
Miastenia Gravis , Calidad de Vida , Humanos , Síndrome , Psicometría , Estudios Transversales , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Miastenia Gravis/diagnóstico , Miastenia Gravis/psicología
6.
Artículo en Inglés | MEDLINE | ID: mdl-37884084

RESUMEN

OBJECTIVE: To examine the relationships between post-stroke depression and cognition using network analysis. In particular, we identified central depressive symptoms, central cognitive performances, and bridge components that connect these 2 constructs. DESIGN: An observational study. We applied network analysis to analyze baseline data to visualize and quantify the relationships between depression and cognition. SETTING: Home and Community. PARTICIPANTS: 202 participants with mild-to-moderate stroke (N=202; mean age: 59.7 years; 55% men; 55% Whites; 90% ischemic stroke). INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Patient Health Questionnaire (PHQ-8) for depressive symptoms and the NIH Toolbox Cognitive Battery for cognitive performances. RESULTS: Depressive symptoms were positively intercorrelated with the network, with symptoms from similar domains clustered together. Mood (expected influence=1.58), concentration (expected influence=0.67), and guilt (expected influence=0.63) were the top 3 central depressive symptoms. Cognitive performances also showed similar network patterns, with executive function (expected influence=0.89), expressive language (expected influence=0.68), and processing speed (expected influence=0.48) identified as the top 3 central cognitive performances. Psychomotor functioning (bridge expected influence=2.49) and attention (bridge expected influence=1.10) were the components connecting depression and cognition. CONCLUSIONS: The central and bridge components identified in this study might serve as targets for interventions against these deficits. Future trials are needed to compare the effectiveness of interventions targeting the central and bridge components vs general interventions treating depression and cognitive impairment as a homogenous clinical syndrome.

7.
Proc Natl Acad Sci U S A ; 117(47): 29469-29477, 2020 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-33148807

RESUMEN

The evolution of organic aerosol (OA) and brown carbon (BrC) in wildfire plumes, including the relative contributions of primary versus secondary sources, has been uncertain in part because of limited knowledge of the precursor emissions and the chemical environment of smoke plumes. We made airborne measurements of a suite of reactive trace gases, particle composition, and optical properties in fresh western US wildfire smoke in July through August 2018. We use these observations to quantify primary versus secondary sources of biomass-burning OA (BBPOA versus BBSOA) and BrC in wildfire plumes. When a daytime wildfire plume dilutes by a factor of 5 to 10, we estimate that up to one-third of the primary OA has evaporated and subsequently reacted to form BBSOA with near unit yield. The reactions of measured BBSOA precursors contribute only 13 ± 3% of the total BBSOA source, with evaporated BBPOA comprising the rest. We find that oxidation of phenolic compounds contributes the majority of BBSOA from emitted vapors. The corresponding particulate nitrophenolic compounds are estimated to explain 29 ± 15% of average BrC light absorption at 405 nm (BrC Abs405) measured in the first few hours of plume evolution, despite accounting for just 4 ± 2% of average OA mass. These measurements provide quantitative constraints on the role of dilution-driven evaporation of OA and subsequent radical-driven oxidation on the fate of biomass-burning OA and BrC in daytime wildfire plumes and point to the need to understand how processing of nighttime emissions differs.


Asunto(s)
Contaminantes Atmosféricos/química , Carbono/análisis , Humo , Incendios Forestales , Aerosoles , Monitoreo del Ambiente , Material Particulado , Estados Unidos
8.
J Ren Nutr ; 33(1): 35-44, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35752400

RESUMEN

OBJECTIVES: Although technology-supported interventions are effective for reducing chronic disease risk, little is known about the relative and combined efficacy of mobile health strategies aimed at multiple lifestyle factors. The purpose of this clinical trial is to evaluate the efficacy of technology-supported behavioral intervention strategies for managing multiple lifestyle-related health outcomes in overweight adults with type 2 diabetes (T2D) and chronic kidney disease (CKD). DESIGN AND METHODS: Using a 2 × 2 factorial design, adults with excess body weight (body mass index ≥27 kg/m2, age ≥40 years), T2D, and CKD stages 2-4 were randomized to an advice control group, or remotely delivered programs consisting of synchronous group-based education (all groups), plus (1) Social Cognitive Theory-based behavioral counseling and/or (2) mobile self-monitoring of diet and physical activity. All programs targeted weight loss, greater physical activity, and lower intakes of sodium and phosphorus-containing food additives. RESULTS: Of 256 randomized participants, 186 (73%) completed 6-month assessments. Compared to the ADVICE group, mHealth interventions did not result in significant changes in weight loss, or urinary sodium and phosphorus excretion. In aggregate analyses, groups receiving mobile self-monitoring had greater weight loss at 3 months (P = .02), but between 3 and 6 months, weight losses plateaued, and by 6 months, the differences were no longer statistically significant. CONCLUSIONS: When engaging patients with T2D and CKD in multiple behavior changes, self-monitoring diet and physical activity demonstrated significantly larger short-term weight losses. Theory-based behavioral counseling alone was no better than baseline advice and demonstrated no interaction effect with self-monitoring.


Asunto(s)
Diabetes Mellitus Tipo 2 , Insuficiencia Renal Crónica , Adulto , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Estilo de Vida , Insuficiencia Renal Crónica/terapia , Consejo , Aumento de Peso , Pérdida de Peso , Fósforo , Sodio
9.
Altern Ther Health Med ; 29(8): 898-906, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37708563

RESUMEN

Background: Chemotherapy-induced peripheral neuropathy (CIPN), one of the most common adverse events associated with chemotherapy, may affect efficacy because of the interruption of chemotherapy or change of regimen in severe cases, and may even increase cancer mortality. Relevant data supports the evidence that acupuncture can treat pain and sensory abnormalities. However, choosing the most effective acupuncture therapy is difficult because of the lack of evidence-based medicine and comparisons between different acupuncture therapies for treating CIPN. The aim of this study was to use a network meta-analysis (NMA) to evaluate the efficacy of different acupuncture therapies for CIPN. Methods: We searched Embase, PubMed, Web of Science, The Cochrane Library, The Chinese Journal Full Text Database, Chinese Biomedical Literature Database, and WanFang Database for randomized controlled trials (RCTs) of acupuncture for CIPN. The search period was from the creation of the relevant library to August 10, 2023. A total of 2 investigators independently performed literature screening, data extraction, and risk for bias evaluation. Stata 14.0 software (StataCorp LLC, College Station, Texas USA), was used for the NMA. Results: A total of 13 eligible RCTs involving 746 patients and 6 acupuncture therapies were included in the study. The NMA results showed that electroacupuncture was superior to moxibustion, manual acupuncture, acupoint injection and Western medicine in improving the total effective rate of treatment of CIPN; electroacupuncture + moxibustion was better than manual acupuncture, acupoint injection, and Western medicine. Manual acupuncture's total effective rate was better than Western medicine. However, electroacupuncture was the most effective treatment for CIPN according to the surface under the cumulative ranking curve (SUCRA) ranking. Conclusion: After a comprehensive evaluation of 6 acupuncture therapies for treating CIPN based on NMA, electroacupuncture may be the best option for treating CIPN. However, would be more convincing to get evidence from more RCTs.


Asunto(s)
Terapia por Acupuntura , Antineoplásicos , Moxibustión , Enfermedades del Sistema Nervioso Periférico , Humanos , Metaanálisis en Red , Terapia por Acupuntura/métodos , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Enfermedades del Sistema Nervioso Periférico/terapia , Antineoplásicos/efectos adversos
10.
Sensors (Basel) ; 23(10)2023 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-37430501

RESUMEN

For the existing visual-inertial SLAM algorithm, when the robot is moving at a constant speed or purely rotating and encounters scenes with insufficient visual features, problems of low accuracy and poor robustness arise. Aiming to solve the problems of low accuracy and robustness of the visual inertial SLAM algorithm, a tightly coupled vision-IMU-2D lidar odometry (VILO) algorithm is proposed. Firstly, low-cost 2D lidar observations and visual-inertial observations are fused in a tightly coupled manner. Secondly, the low-cost 2D lidar odometry model is used to derive the Jacobian matrix of the lidar residual with respect to the state variable to be estimated, and the residual constraint equation of the vision-IMU-2D lidar is constructed. Thirdly, the nonlinear solution method is used to obtain the optimal robot pose, which solves the problem of how to fuse 2D lidar observations with visual-inertial information in a tightly coupled manner. The results show that the algorithm still has reliable pose-estimation accuracy and robustness in many special environments, and the position error and yaw angle error are greatly reduced. Our research improves the accuracy and robustness of the multi-sensor fusion SLAM algorithm.

11.
Molecules ; 28(3)2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36770985

RESUMEN

Amphiphilic polysaccharides can be used as wall materials and applied to encapsulate hydrophobic active chemicals; moreover, there is significant demand for novel medical high-molecular-weight materials with various functions. In order to prepare amphiphilic schizophyllan (SPG), octenyl succinic anhydride (OSA) was chosen to synthesize OSA-modified schizophyllan (OSSPG) using an esterified reaction. The modification of OSSPG was demonstrated through FT-IR and thermal analysis. Moreover, it was found that OSSPG has a better capacity for loading curcumin, and the loading amount was 20 µg/mg, which was 2.6 times higher than that of SPG. In addition, a hydrogel made up of PVA, borax, and C-OSSPG (OSSPG loaded with curcumin) was prepared by means of the one-pot method, based on the biological effects of curcumin and the immune-activating properties of SPG. The mechanical properties and biological activity of the hydrogel were investigated. The experimental results show that the dynamic cross-linking of PVA and borax provided the C-OSSPG/BP hydrogel dressing with exceptional self-healing properties, and it was discovered that the C-OSSPG content increased the hydrogel's swelling and moisturizing properties. In fibroblast cell tests, the cells treated with hydrogel had survival rates of 80% or above. Furthermore, a hydrogel containing C-OSSPG could effectively promote cell migration. Due to the excellent anti-inflammatory properties of curcumin, the hydrogel also significantly reduces the generation of inflammatory factors, such as TNF-α and IL-6, and thus has a potential application as a wound dressing medicinal material.


Asunto(s)
Curcumina , Sizofirano , Hidrogeles/química , Curcumina/farmacología , Curcumina/química , Sizofirano/farmacología , Cicatrización de Heridas , Anhídridos Succínicos , Espectroscopía Infrarroja por Transformada de Fourier , Vendajes , Antiinflamatorios/farmacología
12.
BMC Immunol ; 23(1): 25, 2022 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-35606692

RESUMEN

BACKGROUND: Signal transducer and activator of transcription 6 (STAT6) is an intracelluar transcriotion factor and NLRP3 (Nod-like receptor containing a pyrin domain 3) is a component of NLRP3 inflammasome in pyroptotic cells. There was increased activation of STAT6 and expression of NLRP3 in mice with murine acute lung injury (ALI). However, it is unknown their roles in the development of murine ALI. We in this study, investigated the effects of STAT6 signaling on murine ALI and pyroptosis in STAT6 knock-out (KO) mice and macrophages. RESULTS: STAT6 was activated in the lung tissues of mice 2 days after intratracheal treatmemt with 5 mg/kg LPS. Lack of STAT6 expression in KO mice induced more severe lung inflammation, associated with elevated neutrophil influx and expression of TNF-alpha, IL-6 and IL-1beta in the inflamed lung tissues. In addition, the expression of NLRP3, ASC (apoptosis-associated speck-like protein containing a CARD), p-p38 MAPK (p38 mitogen-activated protein kinase) and ratio of LC3-II/I (microtubule-associated protein-1 light chain-3) was increased, accompanied with the increased polarization of Siglec-F(-) subtype macrophages in KO mice with ALI. Further studies in bone marrow-derived macrophages (BMDMs) revealed that lack of STAT6 increased the expression of NLRP3 and p-p38 MAPK, in association with elevated expression of TNF-alpha, IL-1beta and Calreticulin in LPS-treated KO BMDMs. CONCLUSIONS: Lack of STAT6 exacerbated murine ALI through improving the expression of NLRP3 and activation of p38 MAPK in macrophages. STAT6 has an immune suppressive role in the development of ALI and would be a promising therapeutic target in the treatment of ALI and possibly among patients with acute respiratory distress syndrome (ARDS).


Asunto(s)
Lesión Pulmonar Aguda , Proteína con Dominio Pirina 3 de la Familia NLR , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/metabolismo , Animales , Humanos , Inflamasomas/metabolismo , Lipopolisacáridos/farmacología , Macrófagos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Factor de Transcripción STAT6/genética , Factor de Transcripción STAT6/metabolismo , Factor de Transcripción STAT6/farmacología , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
13.
Environ Sci Technol ; 56(6): 3645-3657, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35229595

RESUMEN

Wildfire-influenced air masses under regional background conditions were characterized at the Mt. Bachelor Observatory (∼2800 m a.s.l.) in summer 2019 to provide a better understanding of the aging of biomass burning organic aerosols (BBOAs) and their impacts on the remote troposphere in the western United States. Submicron aerosol (PM1) concentrations were low (average ± 1σ = 2.2 ± 1.9 µg sm-3), but oxidized BBOAs (average O/C = 0.84) were constantly detected throughout the study. The BBOA correlated well with black carbon, furfural, and acetonitrile and comprised above 50% of PM1 during plume events when the peak PM1 concentration reached 18.0 µg sm-3. Wildfire plumes with estimated transport times varying from ∼10 h to >10 days were identified. The plumes showed ΔOA/ΔCO values ranging from 0.038 to 0.122 ppb ppb-1 with a significant negative relation to plume age, indicating BBOA loss relative to CO during long-range transport. Additionally, increases of average O/C and aerosol sizes were seen in more aged plumes. The mass-based size mode was approximately 700 nm (Dva) in the most oxidized plume that likely originated in Siberia, suggesting aqueous-phase processing during transport. This work highlights the widespread impacts that wildfire emissions have on aerosol concentration and properties, and thus climate, in the western United States.


Asunto(s)
Contaminantes Atmosféricos , Incendios Forestales , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Biomasa , Monitoreo del Ambiente , Material Particulado/análisis , Estados Unidos
14.
Acta Pharmacol Sin ; 43(8): 1979-1988, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34934196

RESUMEN

Cardiac hypertrophy, as one of the major predisposing factors for chronic heart failure, lacks effective interventions. Exploring the pathogenesis of cardiac hypertrophy will reveal potential therapeutic targets. S-nitrosylation is a kind of posttranslational modification that occurs at active cysteines of proteins to mediate various cellular processes. We here identified heat shock protein 90 (Hsp90) as a highly S-nitrosylated target in the hearts of rodents with hypertrophy, and the role of Hsp90 in cardiac hypertrophy remains undefined. The S-nitrosylation of Hsp90 (SNO-Hsp90) levels were elevated in angiotensin II (Ang II)- or phenylephrine (PE)-treated neonatal rat cardiomyocytes (NRCMs) in vitro as well as in cardiomyocytes isolated from mice subjected to transverse aortic constriction (TAC) in vivo. We demonstrated that the elevated SNO-Hsp90 levels were mediated by decreased S-nitrosoglutathione reductase (GSNOR) expression during cardiac hypertrophy, and delivery of GSNOR adeno-associated virus expression vectors (AAV9-GSNOR) decreased the SNO-Hsp90 levels to attenuate cardiac hypertrophy. Mass spectrometry analysis revealed that cysteine 589 (Cys589) might be the S-nitrosylation site of Hsp90. Delivery of the mutated AAV9-Hsp90-C589A inhibited SNO-Hsp90 levels and attenuated cardiac hypertrophy. We further revealed that SNO-Hsp90 led to increased interaction of glycogen synthase kinase 3ß (GSK3ß) and Hsp90, leading to elevated GSK3ß phosphorylation and decreased eIF2Bε phosphorylation, thereby aggravating cardiac hypertrophy. Application of GSK3ß inhibitor TWS119 abolished the protective effect of Hsp90-C589A mutation in Ang II-treated NRCMs. In conclusion, this study demonstrates a critical role of SNO-Hsp90 in cardiac hypertrophy, which may be of a therapeutic target for cardiac hypertrophy treatment.


Asunto(s)
Cardiomegalia , Insuficiencia Cardíaca , Angiotensina II/metabolismo , Angiotensina II/farmacología , Animales , Cardiomegalia/patología , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Insuficiencia Cardíaca/metabolismo , Ratones , Ratones Endogámicos C57BL , Miocitos Cardíacos/metabolismo , Ratas , Transducción de Señal
15.
Appl Opt ; 61(2): 540-545, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35200895

RESUMEN

A novel method called even-power phase modulation is proposed in a self-mixing displacement sensor to improve measuring accuracy, to the best of our knowledge, which is realized by combining the even-power fast algorithm with the sinusoidal phase-modulation method. By performing the even-power fast algorithm in the self-mixing interference system, the spectrum of harmonic components is broadened. In this case, the extracted first and second harmonic components in the frequency domain contain rich information, and the displacement of the target can be accurately reconstructed. The principle and signal processing approach are introduced in detail, and the simulation results show that the reconstruction error can be effectively reduced compared with the electro-optic modulator phase modulation method. A series of experiments at different vibration amplitudes is conducted to confirm the feasibility and effectiveness of the method. An amplitude of 120 nm is proved to be measurable, and the absolute error is 10 nm, which shows great potential in the field of non-contact nanometer vibration measurement sensors.

16.
Int J Mol Sci ; 23(10)2022 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-35628620

RESUMEN

3-PBA is a major degradation intermediate of pyrethroids. Its widespread existence in the environment poses a severe threat to the ecosystem and human health. This study evaluated the adsorption capacity of L. plantarum RS20 toward 3-PBA. Batch adsorption experiments indicated that the optimal adsorption conditions were a temperature of 37 °C and initial pH of 6.0-8.0, under which the removal rate was positively correlated with the cell concentration. In addition, there was no link between the incubation time and adsorption rate. The kinetic study showed that the adsorption process fitted well with the pseudo-second-order model, and the adsorption isotherms could be described by both Langmuir and Freundlich equations. Heat and acid treatments showed that the ability of strain RS20 in removing 3-PBA was independent of microbial vitality. Indeed, it was involved with chemisorption and physisorption via the cell walls. The cell walls made the highest contribution to 3-PBA removal, according to the adsorption experiments using different cellular components. This finding was further reconfirmed by SEM. FTIR spectroscopy analysis indicated that carboxyl, hydroxyl, amino groups, and -C-N were the functional sites for the binding of 3-PBA. The co-culture experiments showed that the adsorption of strain RS20 enhanced the degradation of 3-PBA by strain SC-1. Strain RS20 could also survive and effectively remove 3-PBA in simulated digestive juices. Collectively, strain RS20 could be employed as a biological detoxification agent for humans and animals by eliminating 3-PBA from foods, feeds, and the digestive tract in the future.


Asunto(s)
Lactobacillus plantarum , Contaminantes Químicos del Agua , Adsorción , Benzoatos , Ecosistema , Contaminantes Químicos del Agua/química
17.
J Gastroenterol Hepatol ; 36(12): 3429-3437, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34258777

RESUMEN

BACKGROUND AND AIM: Regorafenib is a potent multikinase inhibitor for the second-line targeted therapy against hepatocellular carcinoma (HCC); however, drug resistance is emerging in clinical settings. Although cancer stem cells (CSCs) are considered as key determinate of drug sensitivity, it remains unclear how CSCs may communicate with the differentiated counterparts (non-CSC) to dictate therapeutic efficacy. Therefore, we sought to investigate the regorafenib resistance mechanism of CSCs in HCC. METHODS: We used sphere formation and soft agar colony formation assays to evaluate the stemness capacity of cancer cells. Cell viability assay was performed to detect the sensitivity of cancer cells to regorafenib. Real-time quantitative polymerase chain reaction and western blot were used to analyze gene expression. Mouse xenograft tumor model was performed to assess Regorafenib sensitivity in vivo. RESULTS: Exosomes are highly enriched in CSC supernatant compared with that of non-CSC, and RAB27A mediates exosome secretion from CSCs to maintain stem-like phenotype and regorafenib insensitivity. Moreover, exosomes released by CSCs upregulate the expression of Nanog in non-CSC, while depleting Nanog sensitizes non-CSC to regorafenib in the presence of CSC exosomes. Consistently, analysis of TCGA datasets reveals that RAB27A expression tightly correlates with Nanog in HCC tissues. More importantly, depletion of RAB27A downregulates Nanog expression and sensitizes cancer cells to regorafenib in nude mice. CONCLUSIONS: Our findings suggest that CSCs release exosomes in a RAB27A-dependent manner to induce Nanog expression and regorafenib resistance in differentiated cells, targeting this exosome signaling between distinct cellular subsets may be a potential therapeutic strategy for HCC patients.


Asunto(s)
Carcinoma Hepatocelular , Resistencia a Antineoplásicos , Neoplasias Hepáticas , Proteína Homeótica Nanog , Proteínas rab27 de Unión a GTP , Animales , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Resistencia a Antineoplásicos/genética , Exosomas/metabolismo , Expresión Génica , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Ratones , Ratones Desnudos , Proteína Homeótica Nanog/genética , Células Madre Neoplásicas/metabolismo , Compuestos de Fenilurea/farmacología , Piridinas/farmacología , Proteínas rab27 de Unión a GTP/genética
18.
Environ Sci Technol ; 54(19): 11838-11847, 2020 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-32857515

RESUMEN

Wildfires have a significant adverse impact on air quality in the United States (US). To understand the potential health impacts of wildfire smoke, many epidemiology studies rely on concentrations of fine particulate matter (PM) as a smoke tracer. However, there are many gas-phase hazardous air pollutants (HAPs) identified by the Environmental Protection Agency (EPA) that are also present in wildfire smoke plumes. Using observations from the Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption, and Nitrogen (WE-CAN), a 2018 aircraft-based field campaign that measured HAPs and PM in western US wildfire smoke plumes, we identify the relationships between HAPs and associated health risks, PM, and smoke age. We find the ratios between acute, chronic noncancer, and chronic cancer HAPs health risk and PM in smoke decrease as a function of smoke age by up to 72% from fresh (<1 day of aging) to old (>3 days of aging) smoke. We show that acrolein, formaldehyde, benzene, and hydrogen cyanide are the dominant contributors to gas-phase HAPs risk in smoke plumes. Finally, we use ratios of HAPs to PM along with annual average smoke-specific PM to estimate current and potential future smoke HAPs risks.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Incendios Forestales , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Humo/efectos adversos , Humo/análisis , Estados Unidos
19.
Environ Sci Technol ; 54(10): 5954-5963, 2020 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-32294377

RESUMEN

Wildfires are an important source of nitrous acid (HONO), a photolabile radical precursor, yet in situ measurements and quantification of primary HONO emissions from open wildfires have been scarce. We present airborne observations of HONO within wildfire plumes sampled during the Western Wildfire Experiment for Cloud chemistry, Aerosol absorption and Nitrogen (WE-CAN) campaign. ΔHONO/ΔCO close to the fire locations ranged from 0.7 to 17 pptv ppbv-1 using a maximum enhancement method, with the median similar to previous observations of temperate forest fire plumes. Measured HONO to NOx enhancement ratios were generally factors of 2, or higher, at early plume ages than previous studies. Enhancement ratios scale with modified combustion efficiency and certain nitrogenous trace gases, which may be useful to estimate HONO release when HONO observations are lacking or plumes have photochemical exposures exceeding an hour as emitted HONO is rapidly photolyzed. We find that HONO photolysis is the dominant contributor to hydrogen oxide radicals (HOx = OH + HO2) in early stage (<3 h) wildfire plume evolution. These results highlight the role of HONO as a major component of reactive nitrogen emissions from wildfires and the main driver of initial photochemical oxidation.


Asunto(s)
Contaminantes Atmosféricos/análisis , Incendios Forestales , Aerosoles , Ácido Nitroso/análisis , Humo
20.
J Cell Mol Med ; 23(12): 8101-8113, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31559687

RESUMEN

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) are life-threatening condition in critically ill patients. Resveratrol (Res), a natural polyphenol, has therapeutic effect in animal model with ALI; however, whether Res attenuates ALI through modulation of macrophage phenotypes in the animal model remains unknown. We in this study treated LPS-induced murine ALI with 30 mg/kg Res and observed significantly reduced severity of ALI in the Res-treated mice 48 hours after Res treatment. Neutrophil infiltrates were significantly reduced, accompanied with lower infiltration of CD45+ Siglec F- phenotype macrophages, but higher population of CD45+ Siglec F+ and CD45+ CD206+ alternatively activated macrophages (M2 cells) in the Res-treated mice with ALI. In addition, the expression of IL-1beta and CXCL15 cytokines was suppressed in the treated mice. However, Res treatment in mice with myeloid cell-restricted SOCS3 deficiency did not significantly attenuate ALI severity and failed to increase population of both CD45+ Siglec F+ and CD45+ CD206+ M2 subtype macrophages in the murine ALI. Further studies in wild-type macrophages revealed that Res treatment effectively reduced the expression of IL-6 and CXCL15, and increased the expression of arginase-1, SIRT1 and SOCS3. However, macrophages' lack of SOCS3 expression were resistant to the Res-induced suppression of IL-6 and CXCL15 in vitro. Thus, we conclude that Res suppressed CD45+ Siglec F- and CD45+ CD206- M1 subtype macrophages through SOCS3 signalling in the LPS-induced murine ALI.


Asunto(s)
Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/metabolismo , Lectinas Tipo C/metabolismo , Antígenos Comunes de Leucocito/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Lectinas de Unión a Manosa/metabolismo , Receptores de Superficie Celular/metabolismo , Resveratrol/uso terapéutico , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo , Acetilación , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/genética , Animales , Arginasa/genética , Arginasa/metabolismo , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Modelos Animales de Enfermedad , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolisacáridos , Masculino , Receptor de Manosa , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Resveratrol/farmacología , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Sirtuina 1/genética , Sirtuina 1/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/deficiencia , Proteína 3 Supresora de la Señalización de Citocinas/genética
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