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1.
Ecol Lett ; 27(4): e14403, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38577961

RESUMO

Species interactions such as facilitation and competition play a crucial role in driving species range shifts. However, density dependence as a key feature of these processes has received little attention in both empirical and modelling studies. Herein, we used a novel, individual-based treeline model informed by rich in situ observations to quantify the contribution of density-dependent species interactions to alpine treeline dynamics, an iconic biome boundary recognized as an indicator of global warming. We found that competition and facilitation dominate in dense versus sparse vegetation scenarios respectively. The optimal balance between these two effects was identified at an intermediate vegetation thickness where the treeline elevation was the highest. Furthermore, treeline shift rates decreased sharply with vegetation thickness and the associated transition from positive to negative species interactions. We thus postulate that vegetation density must be considered when modelling species range dynamics to avoid inadequate predictions of its responses to climate warming.


Assuntos
Ecossistema , Árvores , Árvores/fisiologia , Aquecimento Global , Mudança Climática , Clima
2.
Sensors (Basel) ; 24(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38544111

RESUMO

A cyber-physical system (CPS) integrates communication and automation technologies into the operational processes of physical systems. Nowadays, as a complex CPS, an intelligent connected vehicle (ICV) may be exposed to accidental functional failures and malicious attacks. Therefore, ensuring the ICV's safety and security is crucial. Traditional safety/security analysis methods, such as failure mode and effect analysis and attack tree analysis, cannot provide a comprehensive analysis for the interactions between the system components of the ICV. In this work, we merge system-theoretic process analysis (STPA) with the concept phase of ISO 26262 and ISO/SAE 21434. We focus on the interactions between components while analyzing the safety and security of ICVs to reduce redundant efforts and inconsistencies in determining safety and security requirements. To conquer STPA's abstraction in describing causal scenarios, we improved the physical component diagram of STPA-SafeSec by adding interface elements. In addition, we proposed the loss scenario tree to describe specific scenarios that lead to unsafe/unsecure control actions. After hazard/threat analysis, a unified risk assessment process is proposed to ensure consistency in assessment criteria and to streamline the process. A case study is implemented on the autonomous emergency braking system to demonstrate the validation of the proposed method.

3.
J Atten Disord ; 28(5): 872-879, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38327077

RESUMO

OBJECTIVE: Although ADHD is highly heritable, some environmental factors contribute to its development. Given the growing evidence that gut microbiota was involved in psychiatric disorders, we aimed to identify the characteristic composition of the gut microbiota in ADHD. METHODS: We recruited 47 medication-naive children and adolescents with ADHD, and 60 healthy controls (HCs). We used shotgun metagenomics to measure the structure of the gut microbiota and analyzed the difference in bacterial taxa between ADHD and HCs. RESULTS: Significant differences were found between the ADHD and HC groups in both alpha diversity indices (Simpson index, p = .025 and Shannon index, p = .049) and beta diversity indices (Euclidean distance, Bray-Curtis distance, and JSD distance, p < 2.2e-16). Nine representative species best explain the difference. CONCLUSION: Patients with ADHD showed significant differences in the composition of the gut microbiota compared with HCs. These results may help identify potential biomarkers of ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Microbioma Gastrointestinal , Adolescente , Criança , Humanos , Microbioma Gastrointestinal/genética
4.
J Hazard Mater ; 466: 133479, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38244451

RESUMO

In order to clarify the emission characteristics of VOCs during the initial degradation of kitchen waste, a year-long sampling campaign of kitchen waste in residential household municipal solid waste (HMSW) bins was conducted. A total of 93 VOCs with an average annual concentration of 2271 µg/m3 were detected. Alkanes and oxygenated compounds were the dominant released from the initial degradation of kitchen waste. Seasonal and daily variations were observed, with VOC concentrations generally higher in spring (1413 µg/m3) and summer (5882 µg/m3) and lower in autumn (505 µg/m3) and winter (1258 µg/m3). In addition, peak releases occurred earlier in the spring and summer (at 6 h) than in autumn and winter (at 24 h). Correlation analysis showed that ambient temperature correlated significantly with alkanes and oxygenated compounds (P < 0.01). 67 substances have been found to cause odor pollution. Based on the odor index, oxygenated compounds were the most significant odor pollutants. Acetaldehyde and 2-ketone required particular concern because of its high concentration and high odor index. This study not only enriched the understanding of emissions of VOCs from MSW front-end facilities but will also provide a scientific and theoretical basis for holistic management and odor control of MSW.

5.
Environ Sci Pollut Res Int ; 31(1): 785-802, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38017212

RESUMO

There is a considerable challenge to meeting the Sustainable Development Goals (SDGs) of ending poverty and maintaining ecosystems' function in rural areas, largely due to that the rural people's livelihood relied heavily on fragile ecosystems. China is ambitious to solve this issue by enacting economic stimulus policies such as ecological protection compensation and payment for ecosystem services (ESs). However, these interventions are generally based on stockholders' willingness and lack of scientific basis. Here, we firstly combined InVEST model and social-economic data to evaluate the ecosystem services supply and demand (ESSD), by taking 25 key counties to receive assistance in pursuing rural revitalization in Sichuan province as the study cases. The coupling coordination degree model was then employed to measure the coordination relationship of ESSD. Finally, the driving factors were analyzed based on correlation analysis and stepwise regression method. The results showed that all ESs, except carbon sequestration, were oversupplied with significant spatial heterogeneity. From 2000 to 2020, the supply of all ESs increased, in which the food production had the most notable increase ratio amounting to 48.20%, while the demand of water retention and air purification decreased substantially. Due to the inconsistency between cultivated land area and population changes, significant spatial heterogeneity existed in the coordination relationship of food production. The counties with the highest and the lowest annual average coordination index were Yanyuan (0.9950) and Rangtang (0.1208), respectively. The rural employees and the agricultural gross output value were the key positive factors influencing the quantity and coordination of ESSD, while ecological compensation and financial expenditure had no significant impact, further indicating that these policies were not linked to the performance of ecosystems' function. Finally, policy implications were raised. This study provides a scientific framework for enacting the interventions towards ecological sustainability and poverty ending from ESSD perspective.


Assuntos
Agricultura , Ecossistema , Humanos , Sequestro de Carbono , China , Alimentos , Conservação dos Recursos Naturais
6.
Neurosurg Rev ; 46(1): 265, 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37804440

RESUMO

Biopsy is recommended for patients with primary intracranial lymphoma to confirm the diagnosis, but the effect of tumor resection is still controversial. We conducted this retrospective study to better understand the epidemiology of primary intracranial lymphoma in the USA and explore the relationship between surgical resection and prognosis. Data regarding primary intracranial lymphoma, including incidence, were extracted from the SEER database. We analyzed the difference in incidence between different groups of people. We explored the effect of surgery on the survival of patients by the Kaplan-Meier method and evaluated the possible prognostic indicators by multivariate Cox proportional hazards models. The incidence significantly increased with age. The non-Hispanic Asian or Pacific Islander population exhibited the highest incidence, and the incidence was significantly higher in males than females. A total of 6428 cases were included in the cohort study, and most of the patients were diagnosed in the sixth to seventh decade of life. Sixty percent of tumors were supratentorial tumors. Surgery, especially total resection, significantly improved overall survival and cancer-specific survival. The survival of female patients, patients diagnosed before reaching 60 years of age, patients diagnosed after 2010, and patients with supratentorial lymphomas was better than that of their counterparts. The survival of patients with diffuse large B-cell lymphoma was worse than that of their counterparts. We conducted a comprehensive retrospective analysis of patients with primary intracranial lymphoma. We analyzed the difference in incidence between different groups of people. Surgery significantly improved overall and cancer-specific survival. The results of our research can help clinicians and patients better understand the epidemiology and management of primary intracranial lymphoma.


Assuntos
Linfoma Difuso de Grandes Células B , Masculino , Humanos , Feminino , Incidência , Estudos Retrospectivos , Estudos de Coortes , Programa de SEER , Taxa de Sobrevida , Prognóstico , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/epidemiologia , Linfoma Difuso de Grandes Células B/patologia
7.
Chemosphere ; 344: 140286, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37769910

RESUMO

Fungal nitrification is one kind of heterotrophic nitrification that involves certain species of fungi promoting the transformation of organic nitrogen and ammonia nitrogen to nitrite/nitrate. In this study, simulated aerated landfill reactors (SALRs) were constructed to investigate fungal nitrification in aged municipal solid refuse, with a focus on understanding the effect of temperature on the performance of fungal nitrification as well as fungal contribution to ammonia nitrogen transformation. Different nitrogen metabolism patterns have been observed in the system with fungi only (SALRF) and complete microbial consortium, i.e., bacteria + fungi (SALRC). At a temperature of 35 °C, autotrophic nitrification dominated the ammonia nitrogen transformation, while fungal nitrification did not significantly contribute to ammonia removal. However, at elevated temperatures (i.e., 45 °C and 55 °C), fungi played a crucial role in ammonia transformation through fungal assimilation and fungal nitrification, with bacterial function suppressed. Furthermore, 45 °C was found to be the optimal temperature for fungal nitrification, exhibiting the highest nitrification rate (13.98 mg L-1 d-1) which accounted for 49.80% of total nitrification rate in the aerated landfill. High throughput sequencing revealed reshaping of fungal community in response to temperature variation. The abundance of Aspergillus fumigatus, with a relative abundance ranging from 67.13% to 92.71% at elevated temperatures, suggested its significant potential for fungal nitrification. These findings have implications for the promotion of nitrogen cycle through strengthening fungal nitrification in aerated landfill sites which often operate at high temperatures.


Assuntos
Amônia , Nitrificação , Temperatura , Amônia/metabolismo , Reatores Biológicos/microbiologia , Nitrogênio/metabolismo , Instalações de Eliminação de Resíduos , Desnitrificação
8.
Medicine (Baltimore) ; 102(39): e35465, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37773783

RESUMO

RATIONALE: Rectal dedifferentiated liposarcoma (DDL) and DDL with osteosarcomatous differentiation both are extremely unwonted. In addition, there are no reports of simultaneous DDL with osteosarcoma differentiation with small cell lung cancer (SCLC) to date. Therefore, it is imperative to alert clinicians and pathologists to this extremely rare and instructive synchronous tumor. PATIENT CONCERNS: The patient was a 63-year-old male who presented with intermittent hematochezia and a swelling in the anus. Irregular masses were found on computed tomography (CT) examinations of the chest and abdomen respectively. DIAGNOSIS: The final diagnosis of synchronous occurrence of SCLC and primary rectal DDL with osteosarcomatous differentiation was established by radiological, histological, immunohistochemical and molecular findings. INTERVENTIONS: The patient underwent a puncture biopsy of the right lung mass and a complete resection of the rectal mass. OUTCOMES: The patient abandoned treatment, and multiple SCLC metastases appeared multiple metastasis 8 months after the operation. In the end, he expired suddenly due to severe cerebral hemorrhage caused by brain SCLC metastasis. LESSONS: DDL with osteosarcoma differentiation is infrequent, and its accurate diagnosis is based on morphology, immunohistochemistry and the necessary molecular tests. In rare cases, DDL occurs concurrently with other malignancies and and will be a challenge for pathologists and clinicians at this time. Accordingly, a comprehensive examination to identify possible synchronous tumors is very important in clinical practice.


Assuntos
Neoplasias Ósseas , Lipossarcoma , Neoplasias Pulmonares , Osteossarcoma , Carcinoma de Pequenas Células do Pulmão , Masculino , Humanos , Pessoa de Meia-Idade , Lipossarcoma/patologia , Osteossarcoma/patologia , Diferenciação Celular , Neoplasias Pulmonares/secundário
9.
Food Funct ; 14(19): 8951-8963, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37724446

RESUMO

Background: Previous studies have shown the potential role of vitamin K supplementation in the prevention and treatment of many diseases. However, the effect of vitamin K supplementation on blood glucose remains controversial. The purpose of this study was to assess the effects of vitamin K supplementation on glycemia-related indicators, including Fasting Blood Sugar (FBS), Fasting Insulin (FINS) and Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). The potential association between vitamin K and type 2 diabetes mellitus (T2DM) risk was also evaluated. Methods: Up to April 2023, Cochrane, PubMed, Web of Science, Medline and EMBASE databases were searched to assess the effects of vitamin K on blood glucose and the risk of developing T2DM. Results: A meta-analysis of seven studies (813 participants) found vitamin K supplementation significantly reduced FBS (SMD = -0.150 mg dl-1, 95% CI = -0.290, -0.010 mg dl-1) and HOMA-IR (SMD = -0.200, 95% CI = -0.330, -0.060), but not FINS. Five studies with a total of 105 798 participants were included in the meta-analysis of the association between vitamin K and T2DM. The results showed that vitamin K was associated with the reduced risk of developing T2DM (HR = 0.79, 95% CI [0.71-0.88], P < 0.001). Conclusion: The meta-analysis demonstrated that vitamin K supplementation had a significant effect on the regulation of FBS and HOMA-IR in the population. Moreover, vitamin K was associated with the reduced risk of developing T2DM. Considering some limitations found in this study, additional data from large clinical trials are needed.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Vitamina K , Humanos , Glicemia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Suplementos Nutricionais , Insulina , Resistência à Insulina/fisiologia
10.
Sci Total Environ ; 904: 166672, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37657538

RESUMO

Microbial (bacteria and fungi) community structures and their distributions in urban household municipal solid waste (HMSW) were characterized in a sampling campaign in 38 cities of China covering 5 climatic zones. All samples were collected from garbage containers in residential communities during the Winter of 2022, from January 11 to 26. A total of 247 bacterial genera belonging to 22 phyla were identified among the samples. Firmicutes (44.3 %), Bacteroidetes (33.77 %) and Proteobacteria (21.54 %) were the top 3 dominant phyla, and Arcicella (33.11 %) and Leuconostoc (21.87 %) were the dominant genera. Meanwhile, 124 fungal genera from 7 fungal phyla were detected. Ascomycota was the most dominant phylum, with an average relative abundance of 77.31 %. Hanseniaspora (24.03 %), Debaryomyces (13.47 %), Candida (12.18) were the top 3 dominant fungal genera. Alpha-diversity analysis showed that the species richness and diversity of bacterial and fungal communities of HMSW samples belonging to different climatic zones did not differ significantly. Nonmetric multidimensional scaling (NMDS) analysis confirmed that climatic had an effect on microbial communities but did not show a significant correlation. In addition, the distribution of microbial community in different samples from the same climate zone varied considerably, suggesting the HMSW source play important role in shaping microbial community composition. Considering that residential HMSW is relatively fresh, we speculates that the original microorganisms residing in different components of HMSW are key influencing factor for the community, while the reshaping force driven by environmental conditions are relatively weak. In addition, the study identified 13 bacterial and 16 fungal pathogens with Pseudomonas putida (0.25 %) and Sclerotinia sclerotiorum (2.12 %) as the most abundant potential pathogenic bacteria and fungi, respectively. These findings provide valuable information for characterizing microbial features and potential risks of HMSW in its management system.


Assuntos
COVID-19 , Resíduos Sólidos , Humanos , Bactérias , China/epidemiologia , Surtos de Doenças
11.
12.
Curr Opin Clin Nutr Metab Care ; 26(6): 543-550, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37555800

RESUMO

PURPOSE OF REVIEW: This review will highlight recent studies that have examined the endothelial glycocalyx in a variety of health conditions, as well as potential glycocalyx-targeted therapies. RECENT FINDINGS: A degraded glycocalyx is present in individuals that consume high sodium diet or have kidney disease, diabetes, preeclampsia, coronavirus disease 2019 (COVID-19), or sepsis. Specifically, these conditions are accompanied by elevated glycocalyx components in the blood, such as syndecan-1, syndecans-4, heparin sulfate, and enhanced heparinase activity. Impaired glycocalyx barrier function is accompanied by decreased nitric oxide bioavailability, increased leukocyte adhesion to endothelial cells, and vascular permeability. Glycocalyx degradation appears to play a key role in the progression of cardiovascular complications. However, studies that have used glycocalyx-targeted therapies to treat these conditions are scarce. Various therapeutics can restore the glycocalyx in kidney disease, diabetes, COVID-19, and sepsis. Exposing endothelial cells to glycocalyx components, such as heparin sulfate and hyaluronan protects the glycocalyx. SUMMARY: We conclude that the glycocalyx is degraded in a variety of health conditions, although it remains to be determined whether glycocalyx degradation plays a causal role in disease progression and severity, and whether glycocalyx-targeted therapies improve patient health outcomes. Future studies are warranted to investigate therapeutic strategies that target the endothelial glycocalyx.


Assuntos
COVID-19 , Diabetes Mellitus , Nefropatias , Sepse , Humanos , Células Endoteliais/metabolismo , Glicocálix/metabolismo , COVID-19/metabolismo , Heparina/metabolismo , Diabetes Mellitus/metabolismo , Nefropatias/metabolismo , Sulfatos/metabolismo , Endotélio Vascular
13.
Nutrients ; 15(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37432260

RESUMO

Sulforaphane (SFN), an isothiocyanate, is one of the major dietary phytochemicals found in cruciferous vegetables. Many studies suggest that SFN can protect against cancer and cardiometabolic diseases. Despite the proposed systemic and local vascular protective mechanisms, SFN's potential to inhibit atherogenesis by targeting macrophages remains unknown. In this study, in high fat diet fed ApoE-deficient (ApoE-/-) mice, oral SFN treatment improved dyslipidemia and inhibited atherosclerotic plaque formation and the unstable phenotype, as demonstrated by reductions in the lesion areas in both the aortic sinus and whole aorta, percentages of necrotic cores, vascular macrophage infiltration and reactive oxygen species (ROS) generation. In THP-1-derived macrophages, preadministration SFN alleviated oxidized low-density lipoprotein (ox-LDL)-induced lipid accumulation, oxidative stress and mitochondrial injury. Moreover, a functional study revealed that peritoneal macrophages isolated from SFN-treated mice exhibited attenuated cholesterol influx and enhanced apolipoprotein A-I (apoA-I)- and high-density lipoprotein (HDL)-mediated cholesterol efflux. Mechanistic analysis revealed that SFN supplementation induced both intralesional and intraperitoneal macrophage phenotypic switching toward high expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and ATP-binding cassette subfamily A/G member 1 (ABCA1/G1) and low expression of peroxisome proliferator-activated receptor γ (PPARγ) and cluster of differentiation 36 (CD36), which was further validated by the aortic protein expression. These results suggest that the regulation of macrophages' cholesterol transport and accumulation may be mainly responsible for SFN's potential atheroprotective properties, and the regulatory mechanisms might involve upregulating ABCA1/G1 and downregulating CD36 via the modulation of PPARγ and Nrf2.


Assuntos
Aterosclerose , Células Espumosas , Animais , Camundongos , Fator 2 Relacionado a NF-E2 , PPAR gama , Macrófagos , Isotiocianatos/farmacologia , Aterosclerose/tratamento farmacológico , Aterosclerose/etiologia , Aterosclerose/prevenção & controle
14.
J Colloid Interface Sci ; 649: 279-289, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37348347

RESUMO

Due to the rapid growth of electronic equipment technology, efficient electromagnetic shielding materials are needed for equipment and human protection. Among them, foam shielding materials with absorption as the primary mechanism have higher application value than highly reflective materials. Highly absorbing shielding materials can reduce the secondary pollution caused by electromagnetic wave reflection. In this study, we added Fe3O4@Polyvinyl alcohol (Fe3O4@PVA) and graphene oxide@silver (GO@Ag) into the polyurethane (PU) matrix and constructed Fe3O4@PVA and GO@Ag/PU composite foam by foaming. Fe3O4@PVA and GO@Ag form an excellent network structure in the PU foam skeleton, significantly improving its electromagnetic shielding effectiveness (EMI SE) and mechanical properties. The shielding effectiveness reached 30.9 dB with a specific EMI SE (SSE) of 274.9 dB × cm3 × g-1 at a Fe3O4@PVA filling of 7 wt%, where the electromagnetic wave absorption accounted for more than 80 % of the total EMI SE, proving absorption as the primary shielding mechanism. The results show that Fe3O4, as a ferromagnet, has both the dielectric loss of ferroelectric materials and the hysteresis loss of ferromagnetic materials in electromagnetic shielding, effectively improving the wave absorption performance of composite shielding materials. Therefore, this work provides a promising idea for efficient and lightweight wave-absorbing shielding materials in aerospace, portable electronic devices and lightweight wearable devices.

15.
Sci Rep ; 13(1): 9372, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296187

RESUMO

Neuromyelitis optica spectrum disorders (NMOSD) are severe inflammatory disorders of the central nervous system targeting aquaporin-4 (AQP4). The risk factors for NMOSD remain to be determined, though they may be related to diet and nutrition. This study aimed to explore the possibility of a causal relationship between specific food intake and AQP4-positive NMOSD risk. The study followed a two-sample Mendelian randomization (MR) design. Genetic instruments and self-reported information on the intake of 29 types of food were obtained from a genome-wide association study (GWAS) on 445,779 UK Biobank participants. A total of 132 individuals with AQP4-positive NMOSD and 784 controls from this GWAS were included in our study. The associations were evaluated using inverse-variance-weighted meta-analysis, weighted-median analysis, and MR-Egger regression. A high consumption of oily fish and raw vegetables was associated with a decreased risk of AQP4-positive NMOSD (odds ratio [OR] = 1.78 × 10-16, 95% confidence interval [CI] = 2.60 × 10-25-1.22 × 10-7, p = 0.001; OR = 5.28 × 10-6, 95% CI = 4.67 × 10-11-0.598, p = 0.041, respectively). The results were consistent in the sensitivity analyses, and no evidence of directional pleiotropy was observed. Our study provides useful implications for the development of AQP4-positive NMOSD prevention strategies. Further research is needed to determine the exact causal relationship and mechanisms underlying the association between specific food intake and AQP4-positive NMOSD.


Assuntos
Neuromielite Óptica , Animais , Neuromielite Óptica/epidemiologia , Neuromielite Óptica/genética , Neuromielite Óptica/complicações , Verduras/genética , Estudo de Associação Genômica Ampla , Distribuição Aleatória , Aquaporina 4/genética , Autoanticorpos/genética
16.
J Appl Physiol (1985) ; 134(5): 1224-1231, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37022961

RESUMO

Female mice have a greater capacity for exercising in the heat than male mice, reaching greater power output and longer times of heat exposure before succumbing to exertional heat stroke (EHS). Differences in body mass, size, or testosterone do not explain these distinct sex responses. Whether the ovaries could account for the superior exercise capacity in the heat in females remains unknown. Here, we determined the influence of ovariectomy (OVX) on exercise capacity in the heat, thermoregulation, intestinal damage, and heat shock response in a mouse EHS model. We performed bilateral OVX (n = 10) or sham (n = 8) surgeries in young adult (4 mo) female C57/BL6J mice. Upon recovery from surgeries, mice exercised on a forced wheel placed inside an environmental chamber set at 37.5 °C and 40% relative humidity until experiencing loss of consciousness (LOC). Terminal experiments were performed 3 h after LOC. OVX increased body mass by the time of EHS (sham = 3.8 ± 1.1, OVX = 8.3 ± 3.2 g, P < 0.05), resulted in shorter running distance (sham = 753 ± 189, OVX = 490 ± 87 m, P < 0.05), and shorter time to LOC (sham = 126.3 ± 21, OVX = 99.1 ± 19.8 min, P < 0.05). Histopathological assessment of the intestines revealed damage in the jejunum (sham = 0.2 ± 0.7, OVX = 2.1 ± 1.7 AU, P < 0.05) and ileum (sham = 0.3 ± 0.5, OVX = 1.8 ± 1.4 AU, P < 0.05). OVX increased mesenteric microvascular density (sham = 101 ± 25, OVX = 156 ± 66 10-2 mm/mm2, P < 0.05) and decreased concentration of circulatory heat shock protein 72 (HSP72) (sham = 26.7 ± 15.8, OVX = 10.3 ± 4.6 ng/mL, P < 0.05). No differences were observed in cytokines or chemokines between groups. Our findings indicate that OVX aggravates the pathophysiological response to EHS in mice.NEW & NOTEWORTHY Females outperform males in a mouse model of exertional heat stroke (EHS). Here, we show for the first time the impact of ovariectomy (OVX) on EHS pathophysiology. OVX resulted in a shorter exercise capacity in the heat, greater intestinal damage, and lower heat shock response following EHS.


Assuntos
Golpe de Calor , Humanos , Camundongos , Masculino , Feminino , Animais , Citocinas , Ovariectomia
18.
Am J Physiol Heart Circ Physiol ; 324(4): H473-H483, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36735405

RESUMO

Excess salt consumption contributes to hypertension and arterial dysfunction in humans living in industrialized societies. However, this arterial phenotype is not typically observed in inbred, genetically identical mouse strains that consume a high-salt (HS) diet. Therefore, we sought to determine the effects of HS diet consumption on systolic blood pressure (BP) and arterial function in UM-HET3 mice, an outbred, genetically diverse strain of mice. Male and female UM-HET3 mice underwent a low-salt [LS (1% NaCl)] or HS (4% NaCl) diet for 12 wk. Systolic BP and aortic stiffness, determined by pulse wave velocity (PWV), were increased in HS after 2 and 4 wk, respectively, compared with baseline and continued to increase through week 12 (P < 0.05). Systolic BP was higher from weeks 2-12 and PWV was higher from weeks 4-12 in HS compared with LS mice (P < 0.05). Aortic collagen content was ∼81% higher in HS compared with LS (P < 0.05), whereas aortic elastin content was similar between groups (P > 0.05). Carotid artery endothelium-dependent dilation (EDD) was ∼10% lower in HS compared with LS (P < 0.05), endothelium-independent dilation was similar between groups (P > 0.05). Finally, there was a strong relationship between systolic BP and PWV (r2 = 0.40, P < 0.05), as well as inverse relationship between EDD and systolic BP (r2 = 0.21, P < 0.05) or PWV (r2 = 0.20, P < 0.05). In summary, HS diet consumption in UM-HET3 mice increases systolic BP, which is accompanied by aortic stiffening and impaired EDD. These data suggest that outbred, genetically diverse mice may provide unique translational insight into arterial adaptations of humans that consume an HS diet.NEW & NOTEWORTHY Excess salt consumption is a contributor to hypertension and arterial dysfunction in humans living in industrialized societies, but this phenotype is not observed in inbred, genetically identical mice that consume a high-salt (HS) diet. This study reveals that a HS diet in outbred, genetically diverse mice progressively increases systolic blood pressure and induce arterial dysfunction. These data suggest that genetically diverse mice may provide translational insight into arterial adaptations in humans that consume an HS diet.


Assuntos
Hipertensão , Cloreto de Sódio , Humanos , Masculino , Feminino , Camundongos , Animais , Pressão Sanguínea , Cloreto de Sódio/farmacologia , Análise de Onda de Pulso , Cloreto de Sódio na Dieta , Dieta
19.
J Exerc Sci Fit ; 21(2): 179-185, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36816779

RESUMO

A consensus on the acute cardiovascular responses to low intensity (LI) resistance exercise (RE) combined with blood flow restriction (BFR) has not yet been reached. This study was designed to compare acute cardiovascular responses to a single bout of LIRE, high intensity (HI) RE, and LIRE with BFR in physically active young males. Participants completed 3 RE sessions in random order, where each session consists of 4 sets of unilateral dumbbell bicep curls. Cardiovascular hemodynamics were measured at baseline and right after each set of RE. Aortic augmentation index (AIx) was significantly higher after set 2,3,4 of RE in LI + BFR session compared to LI session (P < 0.05). Brachial systolic blood pressure (SBP), heart rate (HR), brachial rate pressure product (RPP), and central RPP responses did not differ between LI and LI + BFR sessions (P > 0.05). HI session had a higher central SBP, brachial RPP, central RPP, and aortic AIx compared to LI session after each set of RE (P < 0.05), but not brachial SBP (P > 0.05). Taken together, this study showed that LIRE combined with BFR acutely augmented aortic stiffness, as also observed in HI session, but myocardial oxygen consumption was only higher in HI session when compared to LI session. Thus, although BFR did not exaggerate cardiovascular responses nor cause extra myocardial oxygen consumption, it should be prescribed with caution when control of acute aortic stiffening is necessary during RE.

20.
Waste Manag ; 160: 173-181, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36848761

RESUMO

Volatile organic compounds (VOCs) emission on the working face of a large sanitary landfill in northern China was characterized in a one-year long sampling campaign. A total of 67 VOCs with average annual concentration of 2903.01 µg/m3 were detected. Ethanol was the dominant species of detected VOCs, accounting for 76.4-82.3% of the total volatile organic compounds (TVOCs) concentration. VOCs emission showed seasonal variation as the highest concentration was detected in summer and lowest appeared in winter. Furthermore, 50 VOCs identified were non-carcinogenic chemicals and 21 of them were carcinogenic chemicals. Risk assessment showed that the average total non-carcinogenic risk value (HIT) was 4.95, which far exceeded the threshold value of 1; and the average total carcinogenic risk value (RiskT) was 8.45 × 10-5, close to the limit of 1 × 10-4. That means both the non-carcinogenic and carcinogenic risks of long-term exposure to these VOCs could not be ignored. Some of the oxygenated compounds (Acrolein, Ethyl acetate, etc.), halocarbons (1,1,2-Trichloroethane, 1,2-Dichloropropane, etc.) and aromatic compounds (Naphthalene, m + p-Xylene, etc.) consisted the main contributors to non-carcinogenic risks. Meanwhile, carcinogenic risks were mainly caused by halocarbons (cis-1,2-Dichloroethylene, FREON11, etc.) and aromatic compounds (Benzene, Ethylbenzene, etc.). In addition, statistical analysis revealed that the HIT values were related to the concentrations of risk aromatic compounds, halocarbons and hydrocarbons; RiskT values were only related to the concentrations of risk aromatic compounds and halocarbons. The research results provide an important theoretical basis for occupational risk management and VOCs emission prevention in landfills.


Assuntos
Hidrocarbonetos Halogenados , Saúde Ocupacional , Compostos Orgânicos Voláteis , Resíduos Sólidos , Acroleína
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