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Airborne microplastics (MPs) are important pollutants that have been present in the environment for many years and are characterized by their universality, persistence, and potential toxicity. This study investigated the effects of terrestrial and marine transport of MPs in the atmosphere of a coastal city and compared the difference between daytime and nighttime. Laser direct infrared imaging (LDIR) and polarized light microscopy were used to characterize the physical and chemical properties of MPs, including number concentration, chemical types, shape, and size. Backward trajectories were used to distinguish the air masses from marine and terrestrial transport. Twenty chemical types were detected by LDIR, with rubber (16.7%) and phenol-formaldehyde resin (PFR; 14.8%) being major components. Three main morphological types of MPs were identified, and fragments (78.1%) are the dominant type. MPs in the atmosphere were concentrated in the small particle size segment (20-50 µm). The concentration of MPs in the air mass from marine transport was 14.7 items/m3 - lower than that from terrestrial transport (32.0 items/m3). The number concentration of airborne MPs was negatively correlated with relative humidity. MPs from terrestrial transport were mainly rubber (20.2%), while those from marine transport were mainly PFR (18%). MPs in the marine transport air mass were more aged and had a lower number concentration than those in the terrestrial transport air mass. The number concentration of airborne MPs is higher during the day than at night. These findings could contribute to the development of targeted control measures and methods to reduce MP pollution.
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Contaminantes Atmosféricos , Monitoreo del Ambiente , Microplásticos , China , Microplásticos/análisis , Contaminantes Atmosféricos/análisis , Ciudades , Atmósfera/química , Tamaño de la PartículaRESUMEN
As steel production increases, large volumes of highly toxic and nitrogen-rich coking wastewater (CWW) are produced, prompting the development of a novel oxic-hydrolytic-oxic (OHO) biological treatment combination designed for highly efficient removal of nitrogen-contained contaminants. However, previous studies have not comprehensively explored the CWW biotreatment from the perspective of nitrogen metabolism functional genes and pathways. Based on the investigation of taking the full-scale OHO biotreatment combination as a case, it was found that the O1 and O2 bioreactors remove nitrogen through the ammonia assimilation accounting for 33.87% of the total nitrogen (TN) removal rate, while the H bioreactor removes nitrogen through the simultaneous nitrification-denitrification accounting for 61.11% of the TN removal rate. The major ammonia assimilation taxa include Thauera, Immundisolibacter and Thiobacillus; the major nitrifying taxa include Nitrospira and Nitrosomonas; and the major denitrifying taxa include Thiobacillus, Lautropia and Mesorhizobium. Additionally, the H bioreactor exhibits the potential to be optimized for simultaneous nitrification-denitrification coupled with anaerobic ammonium oxidation (Anammox). These understandings will guide the optimization of engineering design and operational practices, contributing to more effective and sustainable wastewater treatment strategies.
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Although the locus coeruleus (LC) is recognized as a crucial modulator for attention and perception by releasing norepinephrine into various cortical regions, the impact of LC-noradrenergic (NE) modulation on auditory discrimination behavior remains elusive. In this study, we firstly recorded local field potential (LFP) and single-unit activity (SUA) in multiple cortical regions associated with auditory-motor processing, including the auditory cortex (AC), posterior parietal cortex (PPC), secondary motor cortex (M2), anterior cingulate cortex (ACC), prefrontal cortex (PFC), and orbitofrontal cortex (OFC), in response to optogenetic activation (40Hz and 0.5s) of the LC-NE neurons in awake mice (male). We found that phasic LC stimulation induced a persistent high gamma oscillations (50 - 80Hz) in the OFC. Phasic activation of LC-NE neurons also resulted in a corresponding increase in NE levels in the OFC, accompanied by a pupillary dilation response. Furthermore, when mice were performing a Go/No-go auditory discrimination task, we optogeneticaly activated the neural projections from LC to OFC, and revealed a shortened latency in behavioral responses to sound stimuli and an increased false alarm rate. These impulsive behavioral responses may be associated with the gamma neural activity in the OFC. These findings have broadened our understanding of the neural mechanisms involved in the role of LC in auditory-motor processing.Significance Statement The locus coeruleus (LC) plays a vital role in mediating behaviors related to perception, but the underlying mechanisms remain unclear. Using optogenetic techniques, we selectively activated the neural projections from the norepinephrine (NE) neurons of LC to the orbitofrontal cortex (OFC). We found that phasical activation of LC neurons increased NE levels in the OFC and induced a gamma band neuronal activity, while also shortening the reaction latency of mice in auditory discrimination tasks, but at the cost of increased false alarm rates. These results reveal a neural mechanism involving the LC in auditory-motor processing, providing a new perspective for understanding attention and perception.
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Critical-sized segmental bone defects cannot heal spontaneously, leading to disability and significant increase in mortality. However, current treatments utilizing bone grafts face a variety of challenges from donor availability to poor osseointegration. Drugs such as growth factors increase cancer risk and are very costly. Here, a porous bioceramic scaffold that promotes bone regeneration via solely mechanobiological design is reported. Two types of scaffolds with high versus low pore curvatures are created using high-precision 3D printing technology to fabricate pore curvatures radius in the 100s of micrometers. While both are able to support bone formation, the high-curvature pores induce higher ectopic bone formation and increased vessel invasion. Scaffolds with high-curvature pores also promote faster regeneration of critical-sized segmental bone defects by activating mechanosensitive pathways. High-curvature pore recruits skeletal stem cells and type H vessels from both the periosteum and the marrow during the early phase of repair. High-curvature pores have increased survival of transplanted GFP-labeled skeletal stem cells (SSCs) and recruit more host SSCs. Taken together, the bioceramic scaffolds with defined micrometer-scale pore curvatures demonstrate a mechanobiological approach for orthopedic scaffold design.
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Y2O3 is a cost-effective and environmentally friendly wide-band gap photocatalyst with extensive application potential. However, its limited ability to be excited by visible light restricts its practical uses. In this study, we coupled the narrow bandgap semiconductor AgI with Y2O3 to form a Z-scheme heterostructure, significantly promoting its photocatalytic degradation activity. Characterization and experimental results demonstrated the formation of Y-O-Ag bonds through coupling with AgI, leading to an increase in oxygen vacancies in Y2O3, which promotes the chemisorption of H2O and O2. The Y-O-Ag bond introduction promotes electron transfer, improves hole utilization, and boosts energy transfer efficiency, thus promoting the efficient generation of ·OH and 1O2. The photocatalytic degradation rates of RhB and o-nitrophenol by 7.5% AgI/Y2O3 were 26.5 and 4 times higher than those of pure Y2O3, respectively. This study provides theoretical support for the Z-scheme heterojunction to improve photocatalytic activity and offers efficient solutions and practical design ideas for sewage purification.
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Biological treatment is commonly used in coking wastewater (CWW) treatment. Prokaryotic microbial communities in CWW treatment have been comprehensively studied. However, viruses, as the critical microorganisms affecting microbial processes and thus engineering parameters, still remain poorly understood in CWW treatment context. Employing viromics sequencing, the composition and function of the viral community in CWW treatment were discovered, revealing novel viral communities and key auxiliary metabolic functions. Caudovirales appeared to be the predominant viral order in the oxic-hydrolytic-oxic (OHO) CWW treatment combination, showing relative abundances of 62.47 %, 56.64 % and 92.20 % in bioreactors O1, H and O2, respectively. At the family level, Myoviridae, Podoviridae and Siphoviridae mainly prevailed in bioreactors O1 and H while Phycodnaviridae dominated in O2. A total of 56.23-92.24% of novel viral contigs defied family-level characterization in this distinct CWW habitat. The virus-host prediction results revealed most viruses infecting the specific functional taxa Pseudomonas, Acidovorax and Thauera in the entire OHO combination, demonstrating the viruses affecting bacterial physiology and pollutants removal from CWW. Viral auxiliary metabolic genes (AMGs) were screened, revealing their involvement in the metabolism of contaminants and toxicity tolerance. In the bioreactor O1, AMGs were enriched in detoxification and phosphorus ingestion, where glutathione S-transferase (GSTs) and beta-ketoadipyl CoA thiolase (fadA) participated in biodegradation of polycyclic aromatic hydrocarbons and phenols, respectively. In the bioreactors H and O2, the AMGs focused on cell division and epicyte formation of the hosts, where GDPmannose 4,6-dehydratase (gmd) related to lipopolysaccharides biosynthesis was considered to play an important role in the growth of nitrifiers. The diversities of viruses and AMGs decreased along the CWW treatment process, pointing to a reinforced virus-host adaptive strategy in stressful operation environments. In this study, the symbiotic virus-bacteria interaction patterns were proposed with a theoretical basis for promoting CWW biological treatment efficiency. The findings filled the gaps in the virus-bacteria interactions at the full-scale CWW treatment and provided great value for understanding the mechanism of biological toxicity and sludge activity in industrial wastewater treatment.
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Aguas Residuales , Aguas Residuales/virología , Reactores Biológicos , Bacterias/metabolismo , Eliminación de Residuos Líquidos/métodos , Coque , Virus , SimbiosisRESUMEN
In this work, corn straw was used as raw material, Hummers method and activation were used to adjust the graphite structure in biochar, and preparing straw based biochar (H-BCS) with ultra-high specific surface area (3441.80 m2/g), highly total pore volume (1.9859 cm3/g), and further enhanced physicochemical properties. Compared with untreated straw biochar (BCS), the specific surface area and total pore volume of H-BCS were increased by 47.24 % and 55.85 %, respectively. H-BCS showed good removal ability in subsequent experiments by using chloramphenicol (CP), hexavalent chromium (Cr6+), and crystal violet (CV) as adsorption models. In addition, the adsorption capacities of H-BCS (CP: 1396.30 mg/g, Cr6+: 218.40 mg/g, and CV: 1246.24 mg/g) are not only higher than most adsorbents, even after undergoing 5 cycles of regeneration, its adsorption capacity remains above 80 %, indicating significant potential for practical applications. In addition, we also speculated and analyzed the conjecture about the "graphite-structure regulation" during the preparation process, and finally discussed the possible mechanism during the adsorption processes. We hope this work could provide a new strategy to solve the restriction of biochar performance by further exploring the regulation of graphite structure in carbon materials.
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Carbón Orgánico , Grafito , Contaminantes Químicos del Agua , Carbón Orgánico/química , Grafito/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Adsorción , Eliminación de Residuos Líquidos/métodos , Cromo/química , Contaminación del Agua/prevención & control , Zea mays/química , Purificación del Agua/métodosRESUMEN
To explore the impact of different functional groups on Hg(II) adsorption, a range of poly(pyrrole methane)s functionalized by -Cl, -CN, -NH2, -OH and -COOH were synthesized and applied to reveal the interaction between different functional groups and mercury ions in water, and the adsorption mechanism was revealed through combined FT-IR, XPS, and DFT calculations. The adsorption performance can be improved to varying degrees by the incorporation of functional groups. Among them, the oxygen-containing functional groups (-OH and -COOH) exhibit stronger affinity for Hg(II) and can increase the adsorption capacity from 180 mg g-1 to more than 1400 mg g-1 at 318 K, with distribution coefficient (Kd) exceeding 105 mL g-1. The variations in the capture and immobilization capabilities of functionalized poly(pyrrole methane)s predominantly stem from the unique interactions between their functional groups and mercury ions. In particular, oxygen-containing -OH and -COOH effectively capture Hg(OH)2 through hydrogen bonding, and further deprotonate to form the -O-Hg-OH and -COO-Hg-OH complexes which are more stable than those obtained from other functionalized groups. Finally, the ecological safety has been fully demonstrated through bactericidal and bacteriostatic experiments to prove the functionalized poly(pyrrole methane)s can be as an environmentally friendly adsorbent for purifying contaminated water.
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Mercurio , Metano , Contaminantes Químicos del Agua , Purificación del Agua , Mercurio/química , Adsorción , Metano/química , Metano/toxicidad , Purificación del Agua/métodos , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad , CinéticaRESUMEN
Bullous pemphigoid (BP) and pemphigus vulgaris (PV) are two common subtypes of autoimmune bullous disease (AIBD). The key role of circulating autoreactive immune cells contributing to skin damage of AIBD has been widely recognized. Nevertheless, the immune characteristics in cutaneous lesions remain unclear. Here, we performed single-cell RNA sequencing (scRNA-seq) and single-cell VDJ sequencing (scRNA-seq) to generate transcriptional profiles for cells and T/B cell clonetype in skin lesions of BP and PV. We found that the proportions of NK&T, macrophages/ dendritic cells, B cells, and mast cells increased in BP and PV lesions. Then, BP and PV cells constituted over 75% of all myeloid cell subtypes, CD4+ T cell subtypes and CD8+ T cell subtypes. Strikingly, CD8+ Trm was identified to be expanded in PV, and located in the intermediate state of the pseudotime trajectory from CD8+ Tm to CD8+ Tem. Interestingly, CD8+ Tem and CD4+ Treg highly expressed exhaustion-related genes, especially in BP lesions. Moreover, the enhanced cell communication between stromal cells and immune cells like B cells and macrophages/ dendritic cells was also identified in BP and PV lesions. Finally, clone expansion was observed in T cells of BP and PV compared with HC, while CD8+ Trm represented the highest ratio of hyperexpanded TCR clones among all T cell subtypes. Our study generally depicts a large and comprehensive single-cell landscape of cutaneous lesions and highlights immune cell features in BP and PV. This offers potential research targets for further investigation.
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Penfigoide Ampolloso , Pénfigo , Análisis de la Célula Individual , Humanos , Penfigoide Ampolloso/inmunología , Penfigoide Ampolloso/genética , Penfigoide Ampolloso/patología , Pénfigo/inmunología , Pénfigo/genética , Pénfigo/patología , Análisis de la Célula Individual/métodos , Piel/inmunología , Piel/patología , Linfocitos T CD8-positivos/inmunología , Femenino , Masculino , Análisis de Secuencia de ARN , Linfocitos T CD4-Positivos/inmunología , Macrófagos/inmunología , Linfocitos B/inmunología , Anciano , Células Dendríticas/inmunología , Persona de Mediana EdadRESUMEN
Microplastic (MP) pollution is evolving into one of the most pressing environmental concerns worldwide. This study assessed the impact of economic activities on atmospheric MP pollution across 17 megacities in northern China, analyzing the correlation between the deposition flux of atmospheric MPs and variables such as city population, gross domestic product (GDP), and industrial structure. The results have shown that the MP pollution is obviously impacted by human activities related to increased GDP, population, as well as tertiary service sector, in which the MP pollution shows most close relationship with the GDP growth. Polypropylene, polyamide, polyurethane, and polyethylene were identified as the primary components of atmospheric MPs. The average particle size of MPs in atmospheric dustfall is 78.3 µm, and the frequency of MP particles increases as the particle size decreases. The findings highlight the complex relationship between socio-economic development and atmospheric MP accumulation, providing essential insights for the formulation of targeted emission reduction strategies.
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The improper disposal of large amounts of phosphogypsum generated during the production process of the phosphorus chemical industry (PCI) still exists. The leachate formed by phosphogypsum stockpiles could pose a threat to the ecological environment and human health. Nevertheless, information regarding the harmful effects of phosphogypsum leachate on organisms is still limited. Herein, the physicochemical characteristics of phosphogypsum leachate were analyzed, and its toxicity effect on zebrafish (Danio rerio), particularly in terms of hepatotoxicity and potential mechanisms, were evaluated. The results indicated that P, NH3-N, TN, F-, As, Cd, Cr, Co, Ni, Zn, Mn, and Hg of phosphogypsum leachate exceeded the V class of surface water environmental quality standards (GB 3838-2002) to varying degrees. Acute toxicity test showed that the 96 h LC50 values of phosphogypsum leachate to zebrafish was 2.08 %. Under exposure to phosphogypsum leachate, zebrafish exhibited concentration-dependent liver damage, characterized by vacuolization and infiltration of inflammatory cells. The increased in Malondialdehyde (MDA) content and altered activities of antioxidant enzymes in the liver indicated the induction of oxidative stress and oxidative damage. The expression of apoptosis-related genes (P53, PUMA, Caspase3, Bcl-2, and Bax) were up-regulated at low dosage group and down-regulated at medium and high dosage groups, suggesting the occurrence of hepatocyte apoptosis or necrosis. Additionally, phosphogypsum leachate influenced the composition of the zebrafish gut microbiota by reducing the relative abundance of Bacteroidota, Aeromonas, Flavobacterium, Vibrio, and increasing that of Rhodobacter and Pirellula. Correlation analysis revealed that gut microbiota dysbiosis was associated with phosphogypsum leachate-induced hepatotoxicity. Altogether, exposure to phosphogypsum leachate caused liver damage in zebrafish, likely through oxidative stress and apoptosis, with the intestinal flora also playing a significant role. These findings contribute to understanding the ecological toxicity of phosphogypsum leachate and promote the sustainable development of PCI.
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Sulfato de Calcio , Enfermedad Hepática Inducida por Sustancias y Drogas , Contaminantes Químicos del Agua , Animales , Humanos , Pez Cebra/metabolismo , Estrés Oxidativo , Fósforo/metabolismo , Contaminantes Químicos del Agua/metabolismoRESUMEN
Kerion, a severe manifestation of tinea capitis caused by dermatophytes, is a fungal skin disease primarily affecting children. This report discusses six cases of pediatric kerion that were successfully treated with a combination of photodynamic therapy (PDT) and antifungal agents. Additionally, we conducted a literature review, identifying and analyzing six published reports on kerion and tinea capitis. The characteristics and efficacies of these cases are summarized. In summary, early combination therapy and proactive pre-treatment interventions proved effective in maximizing therapeutic outcomes, reducing disease duration and minimizing adverse reactions such as cicatricial alopecia. This approach has emerged as a favorable choice for the treatment of kerion.
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Antifúngicos , Fotoquimioterapia , Fármacos Fotosensibilizantes , Tiña del Cuero Cabelludo , Humanos , Fotoquimioterapia/métodos , Antifúngicos/uso terapéutico , Fármacos Fotosensibilizantes/uso terapéutico , Masculino , Femenino , Niño , Tiña del Cuero Cabelludo/tratamiento farmacológico , Preescolar , Ácido Aminolevulínico/uso terapéutico , Terapia Combinada , AdolescenteRESUMEN
ABSTRACT: We present 2 cases of diffuse FDG accumulation in the esophagus due to drinking hot water before an 18 F-FDG PET/CT scan. Drinking large volume of hot water immediately before the FDG PET/CT study may lead to challenges in the interpretation of the hypermetabolic esophagus.
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Esófago , Fluorodesoxiglucosa F18 , Calor , Tomografía Computarizada por Tomografía de Emisión de Positrones , Agua , Femenino , Humanos , Masculino , Persona de Mediana Edad , Transporte Biológico , Ingestión de Líquidos , Esófago/diagnóstico por imagen , Esófago/metabolismo , Fluorodesoxiglucosa F18/farmacocinética , Calor/efectos adversos , Agua/metabolismoRESUMEN
ABSTRACT: The involvement of the ureter as a site of metastasis of colorectal cancer is quite rare. Here we present FDG PET/CT findings of the right ureter metastasis from colon cancer in a patient after colectomy 6 years ago. 18 F-FDG PET/CT showed increased 18 F-FDG uptake in the right ureter with SUV max of 4.3. The pathology and immunohistochemistry confirmed the diagnosis of ureter metastasis from colon cancer.
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Neoplasias del Colon , Uréter , Humanos , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de PositronesRESUMEN
ABSTRACT: A 24-year-old man with a history of osteosarcoma presented with swelling in his right thigh for more than 1 year. 18 F-FDG PET/CT demonstrated increased FDG uptake in multiple juxtacortical masses around the prosthesis, which highly suggested the possibility of osteosarcoma recurrence. A biopsy was performed, and the pathology confirmed the diagnosis of particle disease. The current case indicates that particle disease should be considered when interpreting the PET/CT images with high FDG uptake around the prosthesis.
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Neoplasias Óseas , Osteosarcoma , Masculino , Humanos , Adulto Joven , Adulto , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Osteosarcoma/diagnóstico por imagen , Neoplasias Óseas/diagnóstico por imagenRESUMEN
The rapid development of the phosphorus chemical industry has caused serious pollution problems in the regional eco-environment. However, understanding of their ecotoxic effects remains limited. This study aimed to investigate the developmental toxicity of a stream polluted by a phosphorus chemical plant (PCP) on zebrafish embryos. For this, zebrafish embryos were exposed to stream water (0, 25, 50, and 100% v/v) for 96 h, and developmental toxicity, oxidative stress, apoptosis, and DNA damage were assessed. Stream water-treated embryos exhibited decreased hatching rates, heart rates, and body lengths, as well as increased mortality and malformation rates. The general morphology score system indicated that the swim bladder and pigmentation were the main abnormal morphological endpoints. Stream water promoted antioxidant enzymes (superoxide dismutase (SOD), peroxidase (POD), and glutathione peroxidase (GPx)), lipid peroxidation, and DNA damage. It also triggered apoptosis in the embryos' heads, hearts, and spines by activating apoptotic enzymes (Caspase-3 and Caspase-9). Additionally, stream water influenced growth, oxidative stress, and apoptosis-related 19 gene expression. Notably, tyr, sod (Mn), and caspase9 were the most sensitive indicators of growth, oxidative stress, and apoptosis, respectively. The current trial concluded that PCP-polluted stream water exhibited significant developmental toxicity to zebrafish embryos, which was regulated by the oxidative stress-mediated activation of endogenous apoptotic signaling pathways.
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Contaminantes Químicos del Agua , Pez Cebra , Animales , Pez Cebra/metabolismo , Ríos , Embrión no Mamífero , Contaminantes Químicos del Agua/metabolismo , Estrés Oxidativo , Superóxido Dismutasa/metabolismoRESUMEN
BACKGROUND: Angiotensin converting enzyme 2 (ACE2) exerts renoprotective effects in diabetic kidney disease (DKD) by converting angiotensin (Ang) II into Ang (1-7). Previous studies have demonstrated that ACE2 expression in renal tubules is downregulated in DKD, but the mechanism is not fully understood. Sirtuin-1 (Sirt1) is a protein deacetylase that may regulate the activity of the renin-angiotensin system. The present study investigated the effects of Sirt1 on ACE2 expression under high glucose (HG) conditions and the underlying signaling pathway. METHODS AND RESULTS: Rats with DKD and NRK-52E cells cultured with HG were employed in this study. Western blotting, immunohistochemistry detection and qRT-PCR were performed for protein and mRNA expression analyses. Rats subjected to DKD displayed downregulated expression of Sirt1 and ACE2 in kidneys. Resveratrol, an activator of Sirt1, restored ACE2 expression and ameliorated renal injuries. Similarly, pharmacological activation of Sirt1 with SRT1720 markedly upregulated ACE2 in NRK-52E cells cultured with HG, while Sirt1 small interfering RNA (siRNA) further suppressed ACE2 expression. In addition, A disintegrin and metalloproteinase (ADAM) 17 was observed to be upregulated, and its inhibitor, tissue inhibitor of metalloproteinase 3 (TIMP3), was downregulated in the kidneys of diabetic rats and NRK-52E cells incubated with HG. The TIMP3/ADAM17 pathway was involved in the regulation of ACE2 expression, as evidenced by decreased ACE2 expression levels after TIMP3-siRNA pretreatment. SRT1720 ameliorated the imbalance of TIMP3/ADAM17 induced by HG and consequently enhanced the expression of ACE2. Notably, the above effect of SRT1720 on ACE2 was interrupted by TIMP3-siRNA. CONCLUSIONS: Our findings suggest that Sirt1 activation may prevent HG-induced downregulation of renal tubular ACE2 by modulating the TIMP3/ADAM17 pathway. Sirt1 stimulation might be a potential strategy for the treatment of DKD.
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Enzima Convertidora de Angiotensina 2 , Diabetes Mellitus Experimental , Animales , Ratas , Angiotensina II , Regulación hacia Abajo , Glucosa/farmacología , Riñón , ARN Interferente Pequeño , Sirtuina 1/genéticaRESUMEN
OBJECTIVES: To evaluate alveolar bone dimensions and its relationship with tooth movement (retraction, intrusion and torque) during orthodontic treatment with fixed appliance and clear aligners. METHODS: Thirty-two patients were included in this retrospective clinical study. Cone beam computed tomography (CBCT) was collected before and after treatment to measure the volume of dehiscence and fenestrations in the maxillary anterior region, anterior alveolar bone thickness and height and degree of tooth movement. Rank-sum tests were used to compare the differences in alveolar bone defect volumes between clear aligners and fixed appliance, multiple linear regression analysis was used for study evaluation, and kappa statistics were used to assess internal consistency and test-retest reliability. RESULTS: Post-operatively, most alveolar bone defects occurred on the labial side. The incidence of bone fenestration was 23.96% in the clear aligner group and 26.18% in the fixed appliance group, which was higher than the incidence of bone dehiscence (5.21%). The labial bone height decreased by 0.272 mm, and the palatal bone height increased by 0.617 mm for every 1 mm downward intrusion of the anterior tooth apex in the fixed appliance group. In the clear aligner group, there was no significant change in the labial bone height, and the palatal bone height decreased by 0.447 mm for every 1 mm of anterior tooth retraction coronally. CONCLUSIONS: In the fixed appliance group, anterior tooth intrusion and retraction may have led to alveolar bone resorption by its compression at the cervical level. This study provides a three-dimensional tooth movement evaluation method by using CBCT.
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Incisivo , Aparatos Ortodóncicos Removibles , Humanos , Estudios Retrospectivos , Reproducibilidad de los Resultados , Maxilar/cirugía , Extracción Dental , Tomografía Computarizada de Haz Cónico , Remodelación Ósea , Técnicas de Movimiento Dental , Aparatos Ortodóncicos FijosRESUMEN
Atmospheric microplastics (MPs) have received global attention across various sectors of society due to their potential negative impacts. This study aims to understand the physicochemical characteristics of MPs in inland and coastal megacities for raising awareness about the urgent need to reduce plastic pollution. Laser Direct Infrared Imaging (LDIR) and Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDX) techniques were employed to characterize atmospheric MPs in megacities (inland megacity Beijing and coastal megacity Shanghai) in China, focusing on their physicochemical characteristics, including compositional types, number concentration, morphology, size, possible sources, and potential health risks. The LDIR analysis identified sixteen different types of MPs present in the atmospheres of Beijing and Shanghai. The number concentration of atmospheric MPs in Beijing (3.0 items/m3) is 1.8 times that of Shanghai (1.7 items/m3). The study found that the variations in MP pollution between Beijing and Shanghai are influenced by the urban industrial structure and geographical location. Morphological analysis indicates that fragment MPs have the highest relative abundance in Beijing, while fibrous MPs dominate the atmosphere of Shanghai. Additionally, the study assessed the potential health risks of atmospheric MPs to urban residents. The results suggest that residents of Beijing face more severe health risks from atmospheric MPs compared to those in Shanghai. These findings underscore the urgency to address the issue of atmospheric MPs and provide crucial evidence for the formulation of relevant environmental and health policies.