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1.
Sci Adv ; 10(17): eado0225, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669332

RESUMO

Ketones are ubiquitous in bioactive natural products, pharmaceuticals, chemical feedstocks, and synthetic intermediates. Hence, deacylative coupling reactions enable the versatile elaboration of a plethora of chemicals to access complex drug candidates and natural products. Here, we present deacylative arylation and alkynylation strategies for the synthesis of a wide range of alkyl-tethered arenes and alkynes from cyclic ketones and methyl ketones under dual nickel/photoredox catalysis. This reaction begins by generating a pre-aromatic intermediate (PAI) through the condensation of the ketone and N'-methylpicolino-hydrazonamide (MPHA), followed by the oxidative cleavage of the PAI α-C─C bond to form an alkyl radical, which is subsequently intercepted by a Ni complex, facilitating the formation of diverse C(sp3)-C(sp2)/C(sp) bonds with remarkable generality. This protocol features a one-pot reaction capability, high regioselectivity and ring-opening efficiency, mild reaction conditions, and a broad substrate scope with excellent functional group compatibility.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38569204

RESUMO

The aims of this study were (1) to determine how stair-climbing-based exercise snacks (ES) compared to moderate-intensity continuous training (MICT) for improving cardiorespiratory fitness (CRF), and (2) to explore whether ES could improve maximal fat oxidation rate (MFO) in inactive adults. Healthy, young, inactive adults (n: 42, age: 21.6 ± 2.3 years, BMI: 22.5 ± 3.6 kg·m-2, peak oxygen uptake (VO2peak): 33.6 ± 6.3 mL·kg-1·min-1) were randomly assigned to ES, MICT, or Control. ES (n = 14) and MICT (n = 13) groups performed three sessions per week over 6 weeks, while the control group (n = 15) maintained their habitual lifestyle. ES involved 3 × 30 s "all-out" stair-climbing (6 flight, 126 steps, and 18.9 m total height) bouts separated by >1 h rest, and MICT involved 40 min × 60%-70% HRmax stationary cycling. A significant group × time interaction was found for relative VO2peak (p < 0.05) with ES significantly increasing by 7% compared to baseline (MD = 2.5 mL·kg-1·min-1 (95% CI = 1.2, 3.7), Cohen's d = 0.44), while MICT had no significant effects (MD = 1.0 mL·kg-1·min-1 (-1.1, 3.2), Cohen's d = 0.17), and Control experienced a significant decrease (MD = -1.7 mL·kg-1·min-1 (-2.9, -0.4), Cohen's d = 0.26). MFO was unchanged among the three groups (group × time interaction, p > 0.05 for all). Stair climbing-based ES are a time-efficient alternative to MICT for improving CRF among inactive adults, but the tested ES intervention appears to have limited potential to increase MFO.

3.
ACS Appl Mater Interfaces ; 16(10): 12697-12705, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38415652

RESUMO

Flexible zinc-ion batteries (ZIBs) have been considered to have huge potential in portable and wearable electronics due to their high safety, cost efficiency, and considerable energy density. Therein, the design and construction of flexible electrodes significantly determine the performance and lifespan of flexible battery devices. In this work, an ultrathin flexible three-dimensional ordered macroporous (3DOM) Sn@Zn anode (60 µm in thickness) is presented to relieve dendrite growth and expand the lifespan of flexible ZIBs. The 3DOM structure can ensure uniform electric field distribution, guide oriented zinc plating/stripping, and extend the lifespan of anodes. The rich zincophilic Sn sites on the electrode surface significantly facilitate Zn nucleation. Accordingly, a lowered nucleation overpotential of 8.9 mV and an ultralong cycling performance of 2400 h at 0.1 mA cm-2 and 0.1 mAh cm-2 are achieved in symmetric cells, and the 3DOM Sn@Zn anode can also operate in deep cycling for over 200 h at 10 mA cm-2 and 5 mAh cm-2. A flexible 3DOM MnO2/Ni cathode with a high structural stability and a high mass-specific capacity is fabricated to match with the anode to form a flexible ZIB with a total thickness of 200 µm. The flexible device delivers a high volumetric energy density of 11.76 mWh cm-3 at 100 mA gMnO2-1 and a high average open-circuit voltage of 1.5 V and exhibits high-performance power supply under deformation in practical application scenarios. This work may shed some light on the design and fabrication of flexible energy-storage devices.

4.
Cyborg Bionic Syst ; 5: 0076, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38274711

RESUMO

The integration of multiple electrophysiological biomarkers is crucial for monitoring neonatal seizure dynamics. The present study aimed to characterize the temporal dynamics of neonatal seizures by analyzing intrinsic waveforms of epileptic electroencephalogram (EEG) signals. We proposed a complementary set of methods considering envelope power, focal sharpness changes, and nonlinear patterns of EEG signals of 79 neonates with seizures. Features derived from EEG signals were used as input to the machine learning classifier. All three characteristics were significantly elevated during seizure events, as agreed upon by all viewers (P < 0.0001). Envelope power was elevated in the entire seizure period, and the degree of nonlinearity rose at the termination of a seizure event. Epileptic sharpness effectively characterizes an entire seizure event, complementing the role of envelope power in identifying its onset. However, the degree of nonlinearity showed superior discriminability for the termination of a seizure event. The proposed computational methods for intrinsic sharp or nonlinear EEG patterns evolving during neonatal seizure could share some features with envelope power. Current findings may be helpful in developing strategies to improve neonatal seizure monitoring.

5.
Microb Biotechnol ; 16(11): 2114-2130, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37792264

RESUMO

The severity of heat stroke (HS) is associated with intestinal injury, which is generally considered an essential issue for HS. Heat acclimation (HA) is considered the best strategy to protect against HS. In addition, HA has a protective effect on intestinal injuries caused by HS. Considering the essential role of gut microbes in intestinal structure and function, we decided to investigate the potential protective mechanism of HA in reducing intestinal injury caused by HS. HA model was established by male C57BL/6J mice (5-6 weeks old, 17-19 g) were exposed at (34 ± 0.7)°C for 4 weeks to establish an animal HA model. The protective effect of HA on intestinal barrier injury in HS was investigated by 16S rRNA gene sequencing and nontargeted liquid chromatography-mass spectrometry (LC-MS) metabolomics. According to the experimental results, HA can change the composition of the gut microbiota, which increases the proportion of lactobacilli, faecal bacteria, and urinobacteria but decreases the proportion of deoxycholic acid. Moreover, HA can reduce liver and kidney injury and systemic inflammation caused by HS and reduce intestinal injury by enhancing the integrity of the intestinal barrier. In addition, HA regulates inflammation by inhibiting NF-κB signalling and increasing tight junction protein expression in HS mice. HA induces changes in the gut microbiota, which may enhance tight junction protein expression, thereby reducing intestinal inflammation, promoting bile acid metabolism, and ultimately maintaining the integrity of the intestinal barrier. In conclusion, HA induced changes in the gut microbiota. Among the gut microbiota, lactobacilli may play a key role in the potential protective mechanism of HA.


Assuntos
Microbioma Gastrointestinal , Golpe de Calor , Camundongos , Masculino , Animais , RNA Ribossômico 16S/genética , Temperatura Alta , Camundongos Endogâmicos C57BL , Inflamação , Proteínas de Junções Íntimas , Aclimatação
6.
Langmuir ; 39(44): 15653-15664, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37856252

RESUMO

Designing stimulus-switch viscoelastic solutions and Pickering emulsions with reversible CO2-responsive behavior remains a challenge. A rosin-based CO2-responsive surfactant, N-cetyl-maleimidepimaric acid N,N-dimethylenediamide (C16MPAN), was synthesized and used to prepare CO2-triggered viscoelastic solutions and Pickering emulsions. This surfactant exhibited excellent CO2-responsive performance in water and formed a viscoelastic solution. This viscoelastic system was investigated by dynamic light scattering (DLS), rheology, and cryogenic transmission electron microscopy (Cory-TEM). The shear viscosity of the system increased by 3-4 orders of magnitude after bubbling with CO2 and a large number of elongated, flexible, tubular wormlike micelles were observed. Further, Pickering emulsions were prepared by C16MPAN+ synergistically with cellulose nanocrystals (CNCs), whose stability and switchability were investigated via adsorption isotherm, droplet size, contact angle, and macroscopic photographs. C16MPAN+ was adsorbed with CNCs to form mechanical barriers at the oil-water interface, making the emulsion stable for at least three months, and desorption from CNCs enabled emulsion breaking. The cycle could be switched reversibly multiple times and the particle size distribution of emulsion was basically the same. This work enriches the application of biomass resources in intelligent responsive materials.

7.
J Exerc Sci Fit ; 21(4): 345-353, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37701125

RESUMO

Purpose: This study aimed to examine the short-term effects of SARS-CoV-2 infection and return to sport (RTS) on neuromuscular performance, body composition, and mental health in well-trained young kayakers. Methods: 17 vaccinated kayakers (8 male, 9 female) underwent body composition assessment, peak power output bench press (BP), and 40-s maximum repetition BP tests 23.9 ± 1.6 days before and 22.5 ± 1.6 days after a SARS-CoV-2 infection. A linear transducer was used to examine the BP performance. The perception of training load and mental health were quantified with Borg's CR-10 scale and the Hooper questionnaire before and after infection. The difference and relationship of variables were used Wilcoxon test, Student t-test, Pearson's, and Spearman's r correlation coefficients. Results: There was a significant increase in body mass, fat-free mass, and skeletal muscle mass, but no significant changes in body fat, fat mass, and all BP performance after infection (p < 0.05). There was a significant reduction in training hours per week, session rating of perceived exertion (sRPE), internal training load (sRPE-TL), fatigue, muscle soreness levels, and Hooper index, but no changes in sleep quality and stress levels after infection (p < 0.05). The training and mental health during the RTS period was significantly correlated (r = -0.85 to 0.70) with physical performance after infection. Conclusion: A SARS-CoV-2 infection did not appear to impair the upper-body neuromuscular performance and mental health of vaccinated well-trained young kayakers after a short-term RTS period. These findings can assist coaches, and medical and club staff when guiding RTS strategies after other acute infections or similar restrictions.

8.
Ying Yong Sheng Tai Xue Bao ; 34(7): 1779-1786, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37694461

RESUMO

To understand the responses of radial growth to climatic factors and the differences in ecological resilience to drought between a heliophilous species Larix principis-rupprechtii and a shade species Picea meyeri in mixed forests, we developed the tree-ring width chronologies of L. principis-rupprechtii and P. meyeri in three mixed forests based on the samples collected from Toudaogou of Saihanba in Hebei, Ningwu County and Kelan County in Shanxi Province. We analyzed the correlation between climatic factors and various chronologies and examined the differences in resistance (Rc), recovery (Rt), and resilience (Rs) of L. principis-rupprechtii and P. meyeri in response to drought stress. The results showed that the radial growth of L. principis-rupprechtii and P. meyeri was negatively correlated with the mean and maximum air temperature from May to July in three mixed forests, and was positively correlated with the Palmer drought index (PDSI) from May to September. Radial growth decline in trees due to drought stress was significantly different between the two species among the three sites, indicating different physiological and ecological regulation strategies. The resistance of P. meyeri was stronger than that of L. principis-rupprechtii at the three study sites, with stronger resilience and resilient elasticity of L. principis-rupprechtii than P. meyeri. As a result, P. meyeri exhibited greater drought resistance than L. principis-rupprechtii. Under global warming condition, L. principis-rupprechtii might be at greater risk of growth decline than P. meyeri in this region.


Assuntos
Larix , Picea , Secas , Resistência à Seca , Florestas , Árvores
9.
Biomolecules ; 13(3)2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36979471

RESUMO

Macrophages are innate immune cells and often classified as M1 macrophages (pro-inflammatory states) and M2 macrophages (anti-inflammatory states). Exosomes are cell-derived nanovesicles that range in diameter from 30 to 150 nm. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), are abundant in exosomes and exosomal ncRNAs influence immune responses. Exosomal ncRNAs control macrophage-linked intercellular communication via their targets or signaling pathways, which can play positive or negative roles in lung cancer and inflammatory lung disorders, including acute lung injury (ALI), asthma, and pulmonary fibrosis. In lung cancer, exosomal ncRNAs mediated intercellular communication between lung tumor cells and tumor-associated macrophages (TAMs), coordinating cancer proliferation, migration, invasion, metastasis, immune evasion, and therapy resistance. In inflammatory lung illnesses, exosomal ncRNAs mediate macrophage activation and inflammation to promote or inhibit lung damage. Furthermore, we also discussed the possible applications of exosomal ncRNA-based therapies for lung disorders.


Assuntos
Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Humanos , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , MicroRNAs/metabolismo , Neoplasias Pulmonares/patologia , Comunicação Celular , Macrófagos/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-36833806

RESUMO

The outbreak of COVID-19 has drawn wider attention from residents with growing demand for outdoor space in residential areas because of restrictions on residents' mobility, especially in China. However, the high-rise residential complex in China is featured with a high population density along with less outdoor space per household. This means that the current status of outdoor space in residential areas is far from satisfying residents' growing needs. This is consistent with our preliminary survey that highlights general low satisfaction of residents with outdoor space. According to the hierarchical theory of needs, a literature review, and a questionnaire survey, a framework is proposed in this study to examine the universal value system of high-rise residential outdoor space using the Yangtze River Delta Area as a case study. This framework consists of six dimensions, i.e., space physical comfort (physical environment and space size), space function (functional complexity and scale, age-range, and time-range), space safety (daily, social, and hygiene safety), space diversity (spatial layerings, forms, and scales diversity), accessibility (spatial attraction and concentration and path clarity) and sustainability (cultural, social, ecological, and financial sustainability). Consequently, a questionnaire was designed according to the framework and 251 valid questionnaires were received. Then, structural equation modeling (SEM) was undertaken to examine the impact of each dimension on the value of outdoor space and the framework was optimized into four dimensions, i.e., space physical comfort, space function, space safety, and DAT (space diversity, accessibility, and sustainability). Finally, the mechanism of how outdoor space quality influences the high-rise residential complex is analyzed. These findings provide useful input for the future planning and design of high-rise residential areas.


Assuntos
COVID-19 , Rios , Humanos , Meio Social , China , Inquéritos e Questionários
11.
Front Psychol ; 13: 1022966, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324783

RESUMO

Objective: To explore how a stringent campus lockdown affects the physical activity (PA), sleep and mental health of Chinese university students living in student dormitories during the COVID-19 pandemic. Methods: Data on PA, sleep and mental health were collected between 24 March and 4 April 2022 from 2084 university students (mean age = 22.4 years, 61.1% male students) via an online questionnaire distributed by the students' advisers of each dormitory. The Chinese short version of the International Physical Activity Questionnaire (IPAQ-C), Athens Insomnia Scale (CAIS) and General Health Questionnaire 12-item (GHQ-12) were applied. The Mann-Whitney test and Kruskal-Wallis tests were used to evaluate the PA profile differences between genders, before and during the lockdown period and between students' living environments. Chi-squared (χ2) or Fisher's exact test was used to assess changes in health behaviors by gender and students' living environment compared to before the lockdown. A mediation model was used to examine whether sleep disorder mediated the relationship between PA and mental health in different students' living environments. Results: Participants reported a significant decrease in weekly total PA levels (63.9%). Mean daily sedentary time increased by 21.4% and daily lying time increased by 10.7% compared to before lockdown. Among the participants, 21.2% had experienced insomnia, and 39.0% reported having high mental distress. Female students reported 10% higher rates of sleep disorders than male students (p < 0.001), and also experienced a higher incidence of mental disorders (p < 0.001). Students living with three roommates had a larger decrease in frequencies and durations of participation in light PA than other students (p < 0.001). PA was negatively associated with sleep and mental health, and sleep disorder was a mediating factor between PA and mental health in the students living with two and three roommates. Conclusion: This study showed that strict lockdowns within university dormitories during the COVID-19 pandemic had a negative effect on the health of university students by changing their health behaviors, physical activity and sleep. Our findings indicate a need for strategies to promote an active lifestyle for students in space-limited dormitories in order to maintain health during a prolonged lockdown.

12.
Front Genet ; 13: 1003964, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36186445

RESUMO

Acute lung injury (ALI) is a pulmonary illness with a high burden of morbidity and mortality around the world. Chronic lung diseases also represent life-threatening situations. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a type of long non-coding RNA (lncRNA) and is highly abundant in lung tissues. MALAT1 can function as a competitive endogenous RNA (ceRNA) to impair the microRNA (miRNA) inhibition on targeted messenger RNAs (mRNAs). In this review, we summarized that MALAT1 mainly participates in pulmonary cell biology and lung inflammation. Therefore, MALAT1 can positively or negatively regulate ALI and chronic lung diseases (e.g., chronic obstructive pulmonary disease (COPD), bronchopulmonary dysplasia (BPD), pulmonary fibrosis, asthma, and pulmonary hypertension (PH)). Besides, we also found a MALAT1-miRNA-mRNA ceRNA regulatory network in acute and chronic lung diseases. Through this review, we hope to cast light on the regulatory mechanisms of MALAT1 in ALI and chronic lung disease and provide a promising approach for lung disease treatment.

13.
Sports Med Health Sci ; 4(2): 133-139, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35782277

RESUMO

This study investigated the factors that are associated with sleep disturbances among Chinese athletes. Sleep quality and associated factors were assessed by the Athlete Sleep Screening Questionnaire (ASSQ, n â€‹= â€‹394, aged 18-32 years, 47.6% female). Sleep difficulty score (SDS) and level of sleep problem (none, mild, moderate, or severe) were used to classify participants' sleep quality. Categorical variables were analyzed by Chi-square or fisher's exact tests. An ordinal logistic regression analysis was used to explore factors with poor sleep (SDS ≥8). Approximately 14.2% of participants had moderate to severe sleep problem (SDS ≥8). Fifty-nine percent of the athletes reported sleep disturbance during travel, while 43.3% experienced daytime dysfunction when travelling for competition. No significant difference was found in the SDS category between gender, sports level and events. Athletes with evening chronotype were more likely to report worse sleep than athletes with morning and intermediate chronotype (OR, 2.25; 95%CI, 1.44-3.52; p â€‹< â€‹0.001). For each additional year of age, there was an increase of odds ratio for poor sleep quality (OR, 1.15; 95%CI, 1.04-1.26; p â€‹= â€‹0.004), while each additional year of training reduced the odds ratio (OR, 0.95; 95%CI, 0.91-0.99; p â€‹= â€‹0.044). To improve sleep health in athletes, chronotype, travel-related issues, age and years of training should be taken into consideration.

14.
Ecotoxicol Environ Saf ; 242: 113878, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35849902

RESUMO

Nickel-induced allergic contact dermatitis (ACD) is a common skin disease. The mechanism by which nickel causes ACD is not clear. There is no treatment for it, only symptomatic therapy. However, due to the lifetime sensitization characteristics, the recurrence rate in patients is high. T lymphocytes play a key role in nickel-induced ACD. Elucidating the potential mechanism underlying nickel-induced T lymphocyte signalling might make it possible to achieve targeted treatment of nickel-induced ACD. In our study, a phosphoproteomic approach based on tandem mass tag (TMT) labelling and LCMS/MS analyses was employed. An animal model of nickel allergy was established. Splenic T lymphocytes were purified for quantitative phosphoproteomic analysis. The numbers of phosphoproteins, phosphopeptides and phosphosites identified in this study were 3072, 7977 and 10,200, respectively. Comprehensive gene ontology (GO) analysis combined with Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that nickel can significantly affect the phosphorylation of the mTOR signalling pathway in T lymphocytes. Western blotting analysis was used to detect changes in the expression of autophagy-related proteins (Beclin 1, LC3II, and p62). Nickel allergy changed autophagy-related protein expression (p < 0.05). It has been demonstrated that nickel causes autophagy of T lymphocytes in the spleen. Using autophagy inhibitors to intervene, it was found that Th1 differentiation was inhibited, and the expression of Th1-related inflammatory factors was downregulated. Overall, the identification of relevant signalling pathways yielded new insights into the molecular mechanisms underlying nickel allergy and might help in the discovery and development of mechanism-based drugs.


Assuntos
Dermatite Alérgica de Contato , Níquel , Animais , Autofagia , Níquel/toxicidade , Transdução de Sinais , Linfócitos T
15.
Transl Cancer Res ; 11(4): 973-979, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35571672

RESUMO

Background: Small cell lung cancer (SCLC) is clinically the most aggressive subtype of lung cancer, and accounts for about 15% of all newly diagnosed lung cancer cases. Approximately 1/3 of SCLC patients are diagnosed with limited-stage SCLC (LS-SCLC). The standard of treatment for most patients with LS-SCLC is concurrent chemoradiotherapy. LS-SCLC is sensitive to first-line therapy, but has a high recurrence rate and patients show a poor response to second-line treatment. Referring to extensive-stage SCLC (ES-SCLC), durvalumab plus platinum-etoposide chemotherapy has been approved by the Food Drug Administration and National Medical Products Administration. It is hoped that durvalumab will produce good results for LS-SCLC patients. Case Description: In this article, we report the case of a 75-year-old male patient with LS-SCLC of the left lung (tumor, node metastasis stage cT3N0M0 IIB) who received 2 cycles durvalumab plus neoadjuvant chemotherapy. The neoadjuvant therapy was favorable and no adverse events were observed. The assessment of the tumor via Resist1.1 by videography indicated a complete response. Then a thoracoscopic resection of the left lower lobe of the lung was performed under general anesthesia. The operation was successful, and the patient's postoperative recovery was good. Fortunately, the postoperative pathology results showed pathological complete response. After the surgery, the patient received 3 cycles of adjuvant therapy. Now, the patient is still alive and there is no sign of tumor recurrence. Conclusions: This case highlights the benefits of neoadjuvant programmed death-ligand 1 (PD-L1) inhibitor plus chemotherapy and radical surgery for patients with LS-SCLC and identifies a significant treatment option for LS-SCLC patients.

16.
World J Clin Cases ; 10(7): 2330-2335, 2022 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35321175

RESUMO

BACKGROUND: Alström syndrome (AS) is a rare autosomal recessive disease that is generally induced by mutations of the Alström syndrome 1 (ALMS1) gene. We report a case of AS, extend the spectrum of ALMS1 mutations and highlight the biological role of ALMS1 to explore the relationship between dilated cardiomyopathy (DCM) and mutations in ALMS1. CASE SUMMARY: We present the case of an infant with AS mainly manifesting with DCM that was caused by a novel mutation of the ALMS1 gene. Whole-exome sequencing revealed a simultaneous large deletion and point mutation in ALMS1, leading to frameshift and missense mutations, respectively, rather than nonsense or frameshift mutations, which have been reported previously. Upon optimized anti-remodeling therapy, biohumoral exams and arrhythmic burden of the infant were alleviated at follow-up after 6 mo. CONCLUSION: We identified novel mutations of ALMS1 and extended the spectrum of ALMS1 mutations in an infant with AS.

17.
Ecotoxicol Environ Saf ; 228: 112980, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34794024

RESUMO

BACKGROUND: Electromagnetic pollution cannot be ignored. Long-term low-dose electromagnetic field (EMF) exposure can cause central nervous system dysfunction without effective prevention. MATERIALS/METHODS: Male C57BL/6J mice (6-8 weeks, 17-20 g) were used in this study. Depression-like and anxiety-like behaviors detected by behavioral experiments were compared among different treatments. 16S rRNA gene sequencing and non-targeted liquid chromatography-mass spectrometry (LC-MS) metabolomics were used to explore the relationship between EMF exposure and heat acclimation (HA) effects on gut microbes and serum metabolites. RESULTS: Both EMF and HA regulated the proportions of p_Firmicutes and p_Bacteroidota. EMF exposure caused the proportions of 6 kinds of bacteria, such as g_Butyricicoccus and g_Anaerotruncus, to change significantly (p < 0.05). HA restored the balance of gut microbes that was affected by EMF exposure and the proportion of probiotics (g_Lactobacillus) increased significantly (p < 0.01). Serum metabolite analysis suggested that HA alleviated the disturbance of serum metabolites (such as cholesterol and D-mannose) induced by EMF exposure. Both the metabolic KEGG pathways and PICRUSt functional analysis demonstrated that tryptophan metabolism, pyrimidine metabolism and amino acid biosynthesis were involved. CONCLUSIONS: EMF exposure not only led to depression-like neurobehavioral disorders, but also to gut microbiota imbalance. HA alleviated the depression features caused by EMF exposure. Based on the analysis of gut microbiota associated with serum metabolites, we speculated that gut microbiota might play a vital role in the cross-tolerance provided by HA.

18.
Nano Lett ; 21(14): 6064-6070, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34240608

RESUMO

Numerous laboratories have observed random lasing from optically pumped solutions of plasmonic nanoparticles (NPs) suspended with organic dye molecules. The underlying mechanism is typically attributed to the formation of closed-loop optical cavities enabled by the large local field and scattering enhancements in the vicinity of plasmonic NPs. In this manuscript, we propose an alternative mechanism that does not directly require the plasmon resonance. We used high-speed confocal microspectroscopy to observe the photophysical dynamics of NPs in solution. Laser pulses induce the formation of microbubbles that surround and encapsulate the NPs, then sharp peaks <1.0 nm are observed that match the spectral signature of random lasing. Electromagnetic simulations indicate that ensembles of microbubbles may form optical corral containing standing wave patterns that are sufficient to sustain coherent optical feedback in a gain medium. Collectively, these results show that ensembles of plasmonic-induced bubbles can generate optical feedback and random lasing.


Assuntos
Microbolhas , Nanopartículas , Lasers , Luz
19.
Nat Aging ; 1(5): 454-472, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34263179

RESUMO

Cellular senescence restrains the expansion of neoplastic cells through several layers of regulation. We report that the histone H3-specific demethylase KDM4 is expressed as human stromal cells undergo senescence. In clinical oncology, upregulated KDM4 and diminished H3K9/H3K36 methylation correlate with poorer survival of prostate cancer patients post-chemotherapy. Global chromatin accessibility mapping via ATAC-seq, and expression profiling through RNA-seq, reveal global changes of chromatin openness and spatiotemporal reprogramming of the transcriptomic landscape, which underlie the senescence-associated secretory phenotype (SASP). Selective targeting of KDM4 dampens the SASP of senescent stromal cells, promotes cancer cell apoptosis in the treatment-damaged tumor microenvironment (TME), and prolongs survival of experimental animals. Our study supports dynamic changes of H3K9/H3K36 methylation during senescence, identifies an unusually permissive chromatin state, and unmasks KDM4 as a key SASP modulator. KDM4 targeting presents a novel therapeutic avenue to manipulate cellular senescence and limit its contribution to age-related pathologies including cancer.


Assuntos
Neoplasias da Próstata , Fenótipo Secretor Associado à Senescência , Masculino , Animais , Humanos , Epigenômica , Senescência Celular/genética , Cromatina/genética , Microambiente Tumoral
20.
Adv Mater ; 33(31): e2101745, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34146362

RESUMO

Alkali metals have low potentials and high capacities, making them ideal anodes for next-generation batteries, but they suffer major problems, including dendrite growth and low Coulombic efficiency (CE). Achieving uniform metal deposition and having a reliable solid electrolyte interphase (SEI) are the basic requirements for overcoming these problems. Here, a general remedy is reported for various alkali-metal anodes by the supramolecularization of alkali-metal cations with crown ethers that follows a size-matching rule. The positively charged supramolecular complex provides electrostatic shielding layers to regulate metal deposition and suppress dendrite formation. More promisingly, it reforms electric double layers and drives the production of organic-dominated SEIs with improved flexibility that can accommodate large volume changes. The high flexibility of SEIs during metal deposition and dissolution reduces the amount of dead metal and improves CE and cycling stability. Specifically, a 200% excess Li-based full cell has a capacity retention of ≈100% after 100 cycles. This crown-like supramolecularization strategy is a new chemistry that may be used for the production of dendrite-free metal-anode-based batteries not limited to the cases with alkali metal. It is also expected as a practical technology to improve the uniformity of coatings produced in the electrodeposition industry.

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