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1.
Small ; 20(8): e2305453, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37840417

RESUMEN

Morphology regulation and composition design have proved to be effective strategies for the fabrication of desirable microwave absorbers. However, it is still challenging to precisely control the microstructure and components of MAX phases. Herein, an entropy-driven approach, a transition from irregular grains (low entropy) to sheet structure (high entropy), is proposed to modulate the morphology of MAX phases. The theoretical calculation indicates that the morphology evolution can be ascribed to the enlarged energy difference between (11_00) and (0001) facets. The enriched structural defects and optimized morphologies yield significant dipolar polarization, interfacial polarization, multiple reflections, and scattering, which all enhance the electromagnetic wave absorption performance of (V0.25 Ti0.25 Cr0.25 Mo0.25 )2 GaC. Specifically, its minimum reflection loss can reach up to -47.12 dB at 12.13 GHz, and the optimal effective absorption bandwidth is 4.56 GHz (2.03 mm). Meanwhile, (V0.25 Ti0.25 Cr0.25 Mo0.25 )2 GaC shows also pronounced thermal insulation properties affording it good reliability in the harsh working environment. This work offers a novel approach to designing and regulating the morphology of the high entropy MAX phase, and also presents an opportunity to elucidate the relationship between entropy and electromagnetic wave absorption performance.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38728178

RESUMEN

A Gram-negative, facultative anaerobic, non-motile and rod-shaped bacterium, designated 10c7w1T, was isolated from a human gastrointestinal tract. Colonies on agar plates were small, circular, smooth and beige. The optimal growth conditions were determined to be 37 °C, pH 7.0-7.5 and 0 % (w/v) NaCl. Comparative analysis of complete 16S rRNA gene sequences revealed that strain 10c7w1T showed the highest sequence similarity of 95.8 % to Ottowia beijingensis MCCC 1A01410T, followed by Ottowia thiooxydans (95.2 %) JCM 11629T. The average amino acid identity values between 10c7w1T and O. beijingensis MCCC 1A01410T and O. thiooxydans JCM 11629T were above 60 % (71.4 and 69.5 %). The average nucleotide identity values between strain 10c7w1T and O. beijingensis MCCC 1A01410T and O. thiooxydans JCM 11629T were 76.9 and 72.5 %, respectively. The dominant fatty acids (≥10 %) were straight chain ones, with summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c) and C16 : 00 being the most abundant. Q-8 was the only respiratory quinone. The major polar lipids of strain 10c7w1T were phosphatidylethanolamine, diphosphatidylglycerol and unknown lipids. The DNA G+C content of strain 10c7w1T was 63.6 mol%. On the basis of phylogenetic, phenotypic and chemotaxonomic data, strain 10c7w1T is considered to represent a novel species within the genus Ottowia, for which the name Ottowia cancrivicina sp. nov. is proposed. The type strain is 10c7w1T (=MCCC 1H01399T=KCTC 92200T).


Asunto(s)
Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Estómago , ARN Ribosómico 16S/genética , Ácidos Grasos/química , Humanos , ADN Bacteriano/genética , Estómago/microbiología , Hibridación de Ácido Nucleico , Ubiquinona , Fosfolípidos/química
3.
J Math Biol ; 89(2): 16, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890206

RESUMEN

In this paper, a multi-patch and multi-group vector-borne disease model is proposed to study the effects of host commuting (Lagrangian approach) and/or vector migration (Eulerian approach) on disease spread. We first define the basic reproduction number of the model, R 0 , which completely determines the global dynamics of the model system. Namely, if R 0 ≤ 1 , then the disease-free equilibrium is globally asymptotically stable, and if R 0 > 1 , then there exists a unique endemic equilibrium which is globally asymptotically stable. Then, we show that the basic reproduction number has lower and upper bounds which are independent of the host residence times matrix and the vector migration matrix. In particular, nonhomogeneous mixing of hosts and vectors in a homogeneous environment generally increases disease persistence and the basic reproduction number of the model attains its minimum when the distributions of hosts and vectors are proportional. Moreover, R 0 can also be estimated by the basic reproduction numbers of disconnected patches if the environment is homogeneous. The optimal vector control strategy is obtained for a special scenario. In the two-patch and two-group case, we numerically analyze the dependence of the basic reproduction number and the total number of infected people on the host residence times matrix and illustrate the optimal vector control strategy in homogeneous and heterogeneous environments.


Asunto(s)
Número Básico de Reproducción , Simulación por Computador , Conceptos Matemáticos , Modelos Biológicos , Enfermedades Transmitidas por Vectores , Número Básico de Reproducción/estadística & datos numéricos , Enfermedades Transmitidas por Vectores/transmisión , Enfermedades Transmitidas por Vectores/epidemiología , Enfermedades Transmitidas por Vectores/prevención & control , Humanos , Animales , Vectores de Enfermedades , Modelos Epidemiológicos
4.
J Exp Bot ; 74(10): 2956-2967, 2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-36847172

RESUMEN

Eukaryotic cells contain organelles surrounded by monolayer or bilayer membranes. Organelles take part in highly dynamic and organized interactions at membrane contact sites, which play vital roles during development and response to stress. The endoplasmic reticulum extends throughout the cell and acts as an architectural scaffold to maintain the spatial distribution of other membrane-bound organelles. In this review, we highlight the structural organization, dynamics, and physiological functions of membrane contact sites between the endoplasmic reticulum and various membrane-bound organelles, especially recent advances in plants. We briefly introduce how the combined use of dynamic and static imaging techniques can enable monitoring of the cross-talk between organelles via membrane contact sites. Finally, we discuss future directions for research fields related to membrane contact.


Asunto(s)
Orgánulos , Células Vegetales , Orgánulos/metabolismo , Retículo Endoplásmico/metabolismo , Membranas Mitocondriales , Células Eucariotas , Membrana Celular/metabolismo
5.
Microb Pathog ; 174: 105933, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36494022

RESUMEN

Infection with Helicobacter pylori (H. pylori) is prevalent around the world and responsible for gastric cancer (GC). The development of GC from gastritis is closely associated with the bacterial virulence and the body's immune response ability. In this process, interleukin-1ß (IL-1ß) plays an important role. Under H. pylori infection, IL-1ß is highly expressed that result in gastric acid inhibition, GC-related gene methylations and disfunctions, angiogenesis. Nod-like receptor pyrin domain containing 3 (NLRP3) inflammasome mediates IL-1ß maturation in cells such as macrophages, neutrophils and dendritic cells. But how does IL-1ß get released across the cell membrane still unclear. In this review, we focus on the secretion mechanism of IL-1ß across the membrane, and to explore the role of IL-1ß in the progression of GC.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Carcinogénesis , Citocinas , Helicobacter pylori/genética , Interleucina-1beta/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo
6.
Langmuir ; 39(39): 14162-14172, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37722015

RESUMEN

Rapid endothelialization still remains challenging for blood-contacting biomaterials, especially for long-term, functional, small-diameter vascular grafts. The vascular endothelial growth factor (VEGF)-mimicking QK peptide holds great promise in promoting vascular endothelial cellular activities such as adhesion, spreading, proliferation, and migration. Syndecans are transmembrane proteoglycans that are highly expressed on cell surfaces, including vascular endothelial cells, which can act as docking receptors to provide binding sites for a variety of cellular growth and signaling molecules. Herein, a novel peptide QK-AG73 that coupled the QK domain with the syndecan binding peptide AG73 was proposed, aiming to synergistically enhance the interaction with vascular endothelial cells. In addition, mechanically matched bioactive scaffolds based on poly(l-lactide-co-ε-caprolactone) were successfully prepared by surface functionalization of the covalently combined QK-AG73 peptide. The result showed that the adhesion of human umbilical vein endothelial cells (HUVECs) was increased by approximately 2-fold on QK-AG73-modified surface compared with those modified with a single QK or AG73 peptide. Moreover, surface functionalization of electrospun scaffolds by this QK-AG73 peptide was more efficient in specifically promoting the proliferation of HUVECs and allowing them to grow with an elongated cobblestone-like cell morphology. It was hypothesized that both VEGF receptors and transmembrane syndecan receptors were involved in cellular regulation by the QK-AG73 peptide, which resulted in synergistic improvement of the interactions with vascular endothelial cells and provided a promising strategy to promote endothelialization of small-diameter vascular grafts.

7.
Nanotechnology ; 34(36)2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37257441

RESUMEN

The construction of multi-component composites has become an attractive strategy for high-performance microwave absorption through balancing the magnetic and dielectric loss. However, the influences of different components on absorption performance are ambiguous, which has inevitably hampered the widespread applications of microwave absorbents. Herein, we rationally designed the multi-component absorbers of N-doped carbon composited with Fe/Fe3C nanoparticles, and systematically investigated the impacts of Fe/Fe3C nanoparticles and Fe-Nxmoieties on the microwave-absorbing capacities. It is found that the coexisitence of Fe/Fe3C and Fe-Nxis indispensable to realize the strong microwave absorption ability by simultaneously enhancing the dielectric and magnetic loss in the frequency range of 2-18 GHz. As expected, our optimal absorber dispersed in paraffin with a filler loading of 15 wt% exhibits the minimum reflection loss (RLmin) value of -49 dB and the maximum effective absorption bandwidth (BWeff) value of 4.2 GHz at a low thickness. Our work specifies the importance and influence of the coexistence between the Fe-Nxconfigurations and Fe/Fe3C nanoparticles in the carbon-based composites for the superior microwave absorption and inspires the future fabrication of extraordinary materials in the electromagnetic field.

8.
BMC Public Health ; 23(1): 109, 2023 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-36647034

RESUMEN

Preventive behaviors during the COVID-19 pandemic are especially critical to the protection of individuals whose family members or acquaintances have been infected. However, limited research has explored the influence of infection cues on preventive behaviors. This study proposed an interaction model of environment-cognitive/affective-behavior to elucidate the mechanism by which infection cues influence preventive behaviors and the roles of risk perception, negative emotions, and perceived efficacy in that influence. To explore the relationships among these factors, we conducted a cross-sectional online survey in 34 provinces in China during the first wave of the COVID-19 pandemic. A total of 26,511 participants responded to the survey, and 20,205 valid responses (76.2%) were obtained for further analysis. The moderated mediation results show that infection cues positively predicted preventive behaviors in a manner mediated by risk perception and negative emotions. Moreover, perceived efficacy moderated the influence of infection cues not only on preventive behaviors but also on risk perception and negative emotions. The higher the perceived efficacy, the stronger these influences were. These findings validated our model, which elucidates the mechanisms underlying the promoting effect of infection cues on preventive behaviors during the initial stage of the COVID-19 pandemic. The implications of these results for the COVID-19 pandemic and beyond are discussed.


Asunto(s)
COVID-19 , Humanos , COVID-19/prevención & control , COVID-19/psicología , Estudios Transversales , Pandemias/prevención & control , Señales (Psicología) , Conductas Relacionadas con la Salud , Encuestas y Cuestionarios , Emociones , Percepción
9.
J Ultrasound Med ; 42(1): 221-231, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35929079

RESUMEN

OBJECTIVES: To investigate the brain tissue elasticity in normal term and premature neonates using compression elastography and shear wave elastography. METHODS: This prospective observational study enrolled term and premature neonates admitted to the Third Affiliated Hospital of Guangzhou Medical University between July 2019 and December 2020. RESULTS: A total of 106 neonates, including 65 premature neonates and 41 term neonates, were enrolled. The elastic modulus of the frontal white matter in males was significantly lower than in females (11.67 ± 0.98 versus 12.25 ± 1.31, P = .030), but the shear wave velocity of the thalamus in males was significantly lower than in females (1.18 ± 0.13 versus 1.82 ± 0.10, P < .001). There was no significant correlation between real-time body weight and brain tissue elasticity including elastic modulus and shear wave velocity. But, the shear wave velocity of parietal white matter (r = 0.319, P = .014) and thalamus (r = -0.268, P = .040) and the elastic modulus of parietal white matter (r = 0.356, P = .006) were correlated with corrected gestational age. CONCLUSIONS: Clinicians may consider using elastography to determine brain tissue elasticity in term and preterm neonates.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Masculino , Recién Nacido , Femenino , Humanos , Estudios Prospectivos , Elasticidad , Encéfalo/diagnóstico por imagen , Módulo de Elasticidad
10.
Pediatr Radiol ; 53(2): 256-264, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36066614

RESUMEN

BACKGROUND: Dental age estimation is important for developmental assessment and individual identification. The London Atlas, a recently proposed method for dental age estimation, has been reported to perform satisfactorily in various populations. OBJECTIVE: In this study, we assessed the reproducibility, repeatability and applicability of the London Atlas method in the East China population and compared it with the Demirjian method. MATERIALS AND METHODS: We assessed panoramic radiographs of 835 pediatric patients ages 6.0-19.9 years using the London Atlas and the Demirjian method. We employed the intraclass correlation coefficient and Bland-Altman analysis to evaluate reproducibility and repeatability, respectively. We assessed the agreement between dental age and chronological age and calculated 95% and 80% prediction intervals for each dental age stage. Sensitivity, specificity and predictive values were calculated to assess the performance of both methods for identifying threshold ages. RESULTS: The London Atlas has better reproducibility and repeatability (intraclass correlation coefficients: 0.98 and 0.99; 95% limits of agreement: - 1.34 to 1.56 and - 1.22 to 0.88, respectively). Dental age estimated using the London Atlas was closer to chronological age in both genders (median absolute error = 0.58). The 95% prediction intervals for chronological age were wide (0.99 to 9.89 years). CONCLUSION: The London Atlas has excellent reproducibility and repeatability. Thus, it might offer an alternative method for developmental assessment. We observed considerable variation in dental development in the East China population, which needs further research.


Asunto(s)
Determinación de la Edad por los Dientes , Diente , Humanos , Niño , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Lactante , Preescolar , Londres , Reproducibilidad de los Resultados , Determinación de la Edad por los Dientes/métodos , China
11.
Int Heart J ; 64(3): 442-452, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37258120

RESUMEN

Emerging evidence uncovers the important involvement of circular RNAs (circRNAs) in the dysfunction of cardiomyocytes under hypoxia conditions. However, no studies proved whether circTRRAP (hsa_circ_0081241) can participate in cardiomyocyte injury evoked by hypoxia.A qRT-PCR or immunoblotting method was used to evaluate the expression of circTRRAP, miR-761, and mitogen-activated protein kinase kinase kinase 2 (MAP3K2). The direct relationships of circTRRAP/miR-761 and miR-761/MAP3K2 were confirmed by RNA immunoprecipitation (RIP) assay, dual-luciferase reporter assay, and RNA pull-down assay. The effects of the circTRRAP/miR-761/MAP3K2 axis on cell functional behaviors were examined by 5-ethynyl-2'-deoxyuridine (EdU) assay, CCK-8 assay, and flow cytometry. The production levels of proinflammatory cytokines (IL-1ß, TNF-α, and IL-6) were evaluated by enzyme-linked immunosorbent assay.CircTRRAP and MAP3K2 were overexpressed but miR-761 was downregulated in AC16 cardiomyocytes under hypoxia and in the serum of patients with acute myocardial infarction. Silencing circTRRAP attenuated hypoxia-evoked inflammation, apoptosis, and oxidative stress in human AC16 cardiomyocytes. CircTRRAP targeted miR-761, and miR-761 directly targeted and suppressed MAP3K2. CircTRRAP involved the post-transcriptional regulation of MAP3K2 through miR-761, indicating its competing endogenous RNA (ceRNA) activity. Moreover, miR-761 inhibition abolished the effects of circTRRAP depletion in hypoxia-induced cell injury. MAP3K2 silencing phenocopied miR-761 increase in attenuating hypoxia-evoked cardiomyocyte inflammation, apoptosis, and oxidative stress.Our study demonstrates that circTRRAP can protect AC16 cardiomyocytes from hypoxia-evoked injury through the miR-761/MAP3K2 axis.


Asunto(s)
MicroARNs , Miocitos Cardíacos , Humanos , Estrés Oxidativo/genética , Apoptosis/genética , Hipoxia/genética , Inflamación/genética , MicroARNs/genética , MAP Quinasa Quinasa Quinasa 2
12.
Langmuir ; 38(38): 11770-11777, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36164807

RESUMEN

A magnetic surfactant, which combines the properties of a surfactant with magnetic responsiveness, shows great potential in biotechnology, separation, adsorption, and catalysis, especially in non-invasive manipulation through a magnetic field. However, a molecularly magnetic surfactant is usually paramagnetic for the amorphous and less ordered structures. In this work, magnetic surfactant 1-methyl-3-hexadecane-imidazolium [MnCl2Br] (C16M[Mn]) is reported to self-assemble in water. The C16M[Mn] magnetic surfactant self-assembles in water to form a lamellar hydrogel from 10 to 50 wt % at and below room temperature. The hydrogel changes from a gel to a sol at 30 °C, and the hexadecane chains in the hydrogel change from noncrystalline to crystalline at 0 °C. In the hydrogel state, the lamellar domain spacing is varied from 36 to 45 nm depending on the concentration and self-assembly temperature. After self-assembly, the magnetic susceptibility of the freeze-dried magnetic surfactant is increased. Most important is the fact that the freeze-dried sample at a high concentration (40-50 wt %) shows the highest magnetic susceptibility, which is related to the closer molecular packing and the more ordered structures. The self-assembly-induced increase in magnetic susceptibility provides a method for improving the magnetic properties of a magnetic surfactant.

13.
Biomacromolecules ; 23(2): 530-542, 2022 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-34965723

RESUMEN

Ice formation and recrystallization exert severe impairments to cellular cryopreservation. In light of cell-damaging washing procedures in the current glycerol approach, many researches have been devoted to the development of biocompatible cryoprotectants for optimal bioprotection of human erythrocytes. Herein, we develop a novel ACTIVE glycopeptide of saccharide-grafted ε-poly(L-lysine), that can be credited with adsorption on membrane surfaces, cryopreservation with trehalose, and icephilicity for validity of human erythrocytes. Then, by Borch reductive amination or amidation, glucose, lactose, maltose, maltotriose, or trehalose was tethered to ε-polylysine. The synthesized ACTIVE glycopeptides with intrinsic icephilicity could localize on the membrane surface of human erythrocytes and improve cryopreservation with trehalose, so that remarkable post-thaw cryosurvival of human erythrocytes was achieved with a slight variation in cell morphology and functions. Human erythrocytes (∼50% hematocrit) in cryostores could maintain high cryosurvival above 74%, even after plunged in liquid nitrogen for 6 months. Analyses of differential scanning calorimetry, Raman spectroscopy, and dynamic ice shaping suggested that this cryopreservation protocol combined with the ACTIVE glycopeptide and trehalose could enhance the hydrogen bond network in nonfrozen solutions, resulting in inhibition of recrystallization and growth of ice. Therefore, the ACTIVE glycopeptide can be applied as a trehalose-associated "chaperone", providing a new way to serve as a candidate in glycerol-free human erythrocyte cryopreservation.


Asunto(s)
Hielo , Trehalosa , Supervivencia Celular , Criopreservación/métodos , Crioprotectores/farmacología , Eritrocitos , Glicerol/farmacología , Glicopéptidos/farmacología , Humanos , Trehalosa/farmacología
14.
J Appl Toxicol ; 42(10): 1662-1670, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35470462

RESUMEN

Chlorpyrifos and cyfluthrin are insecticides commonly used in agriculture. The mixed residues of chlorpyrifos and cyfluthrin in the aquatic environment may have combined effects on nontarget species. Therefore, studying the combined toxic effects and mechanisms of pesticide mixtures is of great significance to environmental risk assessment. To evaluate the risk of combined exposure, we examined the effects of both compounds, separately and together, on motor activity, acetylcholinesterase (AChE) activity, and neurotransmitter levels in larval zebrafish. Chlorpyrifos exposure significantly reduced functional motor capacity (swim distance and velocity) and enhanced meandering, while cyfluthrin exposure alone had no significant effects on swim parameters. However, combined exposure significantly reduced total swimming distance and mean velocity and increased meandering. Both compounds alone and the combination significantly reduced AChE activity, and the combined effect was antagonistic. Combined exposure also significantly altered the concentrations of serotonin, serotonin precursors, and dopamine precursors, as well as concentrations of the amino acid neurotransmitters glycine, alanine, and aspartic acid. Combined exposure to chlorpyrifos and cyfluthrin exhibited distinct joint action modes in terms of neurobehavior, AChE activity, and neurotransmitter levels, thereby providing an experimental basis for assessing the combined exposure to chlorpyrifos and cyfluthrin's environmental risk.


Asunto(s)
Cloropirifos , Insecticidas , Acetilcolinesterasa/metabolismo , Animales , Cloropirifos/metabolismo , Cloropirifos/toxicidad , Insecticidas/toxicidad , Larva/metabolismo , Neurotransmisores , Nitrilos , Piretrinas , Serotonina/metabolismo , Pez Cebra/metabolismo
15.
J Appl Toxicol ; 42(9): 1524-1532, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35289950

RESUMEN

Inhalation of beryllium and its compounds can cause lung injuries, resulting from inflammation and oxidative stress. Multivesicular bodies (MVB), such as exosomes, are membrane vesicles produced by early and late endosomes that mediate intercellular communications. However, the role of exosomes in beryllium toxicity has not been elucidated. This current study aimed to investigate the functional role of exosomes in lung injury resulting from beryllium sulfate (BeSO4 ). Here, Sprague-Dawley (SD) rats were exposed to 4, 8, and 12 mg/kg BeSO4 by nonexposed intratracheal instillation. Murine macrophage (RAW 264.7) cells were pretreated with 50 nmol/L rapamycin (an mTOR signaling pathway inhibitor) for 30 min and then cultured for 24 h with 100 µg/mL exosomes, which had been previously isolated from the serum of 12 mg/kg BeSO4 -treated SD rats. Compared with those of the controls, exposure to BeSO4 in vivo increased LDH activity, elevated levels of inflammatory cytokines (IL-10, TNF-α, and IFN-γ) alongside inflammation-related proteins expression (COX-2 and iNOS), and enhanced secretion of exosomes from the SD rat's serum. Moreover, the BeSO4 -Exos-induced upregulation of LDH activity and inflammatory responses in RAW 264.7 cells can be alleviated following pretreatment with rapamycin. Collectively, these results suggest that serum exosomes play an important role in pulmonary inflammation induced by BeSO4 in RAW 264.7 cells via the mTOR pathway.


Asunto(s)
Berilio , Exosomas , Animales , Berilio/farmacología , Berilio/toxicidad , Exosomas/metabolismo , Inflamación/inducido químicamente , Macrófagos , Ratones , Ratas , Ratas Sprague-Dawley , Sirolimus/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
16.
J Appl Toxicol ; 42(2): 230-243, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34091916

RESUMEN

Beryllium and its compounds are systemic toxicants that are widely applied in many industries. Hydrogen sulfide has been found to protect cells. The present study aimed to determine the protective mechanisms involved in hydrogen sulfide treatment of 16HBE cells following beryllium sulfate-induced injury. 16HBE cells were treated with beryllium sulfate doses ranging between 0 and 300 µM BeSO4 . Additionally, 16HBE cells were subjected to pretreatment with either a 300 µM dose of sodium hydrosulfide (a hydrogen sulfide donor) or 10 mM DL-propargylglycine (a cystathionine-γ-lyase inhibitor) for 6 hr before then being treated with 150 µM beryllium sulfate for 48 hr. This study illustrates that beryllium sulfate induces a reduction in cell viability, increases lactate dehydrogenase (LDH) release, and increases cellular apoptosis and autophagy in 16HBE cells. Interestingly, pretreating 16HBE cells with sodium hydrosulfide significantly reduced the beryllium sulfate-induced apoptosis and autophagy. Moreover, it increased the mitochondrial membrane potential and alleviated the G2/M-phase cell cycle arrest. However, pretreatment with 10 mM DL-propargylglycine promoted the opposite effects. PI3K/Akt/mTOR and Nrf2/ARE signaling pathways are also activated following pretreatment with sodium hydrosulfide. These results indicate the protection provided by hydrogen sulfide in 16HBE cells against beryllium sulfate-induced injury is associated with the inhibition of apoptosis and autophagy through the activation of the PI3K/Akt/mTOR and Nrf2/ARE signaling pathways. Therefore, hydrogen sulfide has the potential to be a promising candidate in the treatment against beryllium disease.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Berilio/toxicidad , Sulfuro de Hidrógeno/farmacología , Sustancias Protectoras/farmacología , Bronquios , Línea Celular , Células Epiteliales , Humanos
17.
BMC Oral Health ; 22(1): 373, 2022 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-36057573

RESUMEN

BACKGROUND: The comparison of the two Willems dental age estimation methods (gender-specific (Willems I) and non-gender-specific (Willems II)) has not been fully investigated. Here we aimed to explore the applicability of the Willems dental age estimation in an Eastern Chinese population, which may cast light on the field of dental age estimation. METHODS: A total of 1211 oral panoramic radiographs (582 boys and 629 girls) of the Chinese Han population aged 11-16 years old were collected. Dental ages (DAs) were calculated using the Willems method. Statistical significance was set at a p-value < 0.05. Age differences between chronological age (CA) and dental age were analyzed by paired t-tests and mean absolute error (MAE). RESULTS: The differences between CA and DA determined by the Willems I method were + 0.44 and + 0.09 years for boys and girls, respectively. When using the Willems II method, these differences were + 0.57 and - 0.09. The MAEs of the Willems I method between DA and CA were 0.95 and 1.00 years in boys and girls, respectively. For Willems II, MAEs were 1.02 and 1.00 years in boys and girls. CONCLUSIONS: This study showed that the Willems I method was more accurate than the Willems II method in the boys' group for predicting age from a whole scale. In comparison, Willems II is more competitive in the girls' group. Neither method may be satisfactory for 11-to-16-year-old teenagers in Eastern China.


Asunto(s)
Determinación de la Edad por los Dientes , Diente , Adolescente , Determinación de la Edad por los Dientes/métodos , Pueblo Asiatico , Niño , China , Femenino , Humanos , Masculino , Radiografía Panorámica
18.
Bull Math Biol ; 83(11): 111, 2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34581872

RESUMEN

Zika virus disease is a viral disease primarily transmitted to humans through the bite of infected female mosquitoes. Recent evidence indicates that the virus can also be sexually transmitted in hosts and vertically transmitted in vectors. In this paper, we propose a Zika model with three transmission routes, that is, vector-borne transmission between humans and mosquitoes, sexual transmission within humans and vertical transmission within mosquitoes. The basic reproduction number [Formula: see text] is computed and shown to be a sharp threshold quantity. Namely, the disease-free equilibrium is globally asymptotically stable as [Formula: see text], whereas there exists a unique endemic equilibrium which is globally asymptotically stable as [Formula: see text]. The relative contributions of each transmission route on the reproduction number, and the short- and long-term host infections are analyzed. Numerical simulations confirm that vectorial transmission contributes the most to the initial and subsequent transmission. The role of sexual transmission in the early phase of a Zika outbreak is greater than the long term, while vertical transmission is the opposite. Reducing mosquito bites is the most effective measure in lowering the risk of Zika virus infection.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Animales , Número Básico de Reproducción , Femenino , Humanos , Conceptos Matemáticos , Modelos Biológicos , Mosquitos Vectores , Infección por el Virus Zika/epidemiología
19.
J Appl Toxicol ; 41(8): 1275-1285, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33197057

RESUMEN

Beryllium and its compounds are systemic toxicants that mainly accumulate in the lungs. As a regulator of gene expression, microRNAs (miRNAs) were involved in some lung diseases. This study aimed to analyze the levels of some inflammatory cytokine and the differential expressions of miRNAs in human bronchial epithelial cells (16HBE) induced by beryllium sulfate (BeSO4 ) and to further explore the biological functions of differentially expressed miRNAs. The profile of miRNAs in 16HBE cells was detected using the high-throughput sequencing between the control groups (n = 3) and the 150 µmol/L of BeSO4 -treated groups (n = 3). Bioinformatics analysis of differentially expressed miRNAs was performed, including the prediction of target genes, Gene Ontology (GO) analysis, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to verify some damage-related miRNAs. We found that BeSO4 can increase the levels of some inflammatory cytokine such as interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-α), interferon-γ (IFN-γ), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). And BeSO4 altered miRNAs expression of 16HBE cells and a total of 179 differentially expressed miRNAs were identified, including 88 upregulated miRNAs and 91 downregulated miRNAs. The target genes predicted by 28 dysregulated miRNAs were mainly involved in the transcription regulation, signal transduction, MAPK, and VEGF signaling pathway. The qRT-PCR verification results were consistent with the sequencing results. miRNA expression profiling in 16HBE cells exposed to BeSO4 provides new insights into the toxicity mechanism of beryllium exposure.


Asunto(s)
Berilio/toxicidad , Bronquios/efectos de los fármacos , MicroARNs/metabolismo , Mucosa Respiratoria/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Western Blotting , Bronquios/citología , Bronquios/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Mucosa Respiratoria/citología , Mucosa Respiratoria/metabolismo
20.
Pak J Pharm Sci ; 34(1(Special)): 381-386, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34275783

RESUMEN

To investigate the effects of hydralazine combined with nitrate on serum levels of Adropin and brain natriuretic peptide (BNP), left ventricular remodeling and prognosis in patients with chronic heart failure (CHF). 126 CHF patients were divided into control group (n=13, sodium nitroprusside) and combined treatment group (n=63, sodium nitroprusside ± hydralazine). Serum Adropin and BNP levels and left ventricular mass index (LVMI) of patients before treatment and 10 days after treatment were recorded, so did patient's end-point events. It was found that compared with those before treatment, the serum levels of Adropin, BNP, and LVMI in combined group and control group after 10 days of treatment were lower (P<0.05). The end-point event rate in the combined group was 19.05% (12/63). The serum levels of Adropin, BNP, and LVMI in the combined group with end-point events were higher than those of patients without end-point events (P<0.05). Spearman correlation analysis showed that serum levels of Adropin and BNP were positively correlated with LVMI and the end-point events rate (P<0.05). To sum up, hydralazine combined with sodium nitroprusside treatment can effectively reduce serum Adropin and BNP levels, and the risk of left ventricular remodeling and poor prognosis in patients with CHF.


Asunto(s)
Insuficiencia Cardíaca/tratamiento farmacológico , Hidralazina/uso terapéutico , Nitroprusiato/uso terapéutico , Vasodilatadores/uso terapéutico , Remodelación Ventricular , Anciano , Anciano de 80 o más Años , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/diagnóstico por imagen , Humanos , Péptidos y Proteínas de Señalización Intercelular/sangre , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Pronóstico
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