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1.
J Hum Genet ; 69(5): 197-203, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38374166

RESUMEN

CAPZA2 encodes the α2 subunit of CAPZA, which is vital for actin polymerization and depolymerization in humans. However, understanding of diseases associated with CAPZA2 remains limited. To date, only three cases have been documented with neurodevelopmental abnormalities such as delayed motor development, speech delay, intellectual disability, hypotonia, and a history of seizures. In this study, we document a patient who exhibited seizures, mild intellectual disability, and impaired motor development yet did not demonstrate speech delay or hypotonia. The patient also suffered from recurrent instances of respiratory infections, gastrointestinal and allergic diseases. A novel de novo splicing variant c.219+1 G > A was detected in the CAPZA2 gene through whole-exome sequencing. This variant led to exon 4 skipping in mRNA splicing, confirmed by RT-PCR and Sanger sequencing. To our knowledge, this is the third study on human CAPZA2 defects, documenting the fourth unambiguously diagnosed case. Furthermore, this splicing mutation type is reported here for the first time. Our research offers additional support for the existence of a CAPZA2-related non-syndromic neurodevelopmental disorder. Our findings augment our understanding of the phenotypic range associated with CAPZA2 deficiency and enrich the knowledge of the mutational spectrum of the CAPZA2 gene.


Asunto(s)
Proteína CapZ , Discapacidades del Desarrollo , Epilepsia , Heterocigoto , Hipotonía Muscular , Mutación , Preescolar , Femenino , Humanos , Masculino , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/patología , Epilepsia/genética , Secuenciación del Exoma , Discapacidad Intelectual/genética , Discapacidad Intelectual/patología , Hipotonía Muscular/genética , Hipotonía Muscular/patología , Fenotipo , Empalme del ARN/genética , Proteína CapZ/genética
2.
Mol Cell Biochem ; 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38306011

RESUMEN

Alkylation repair homolog protein 5 (ALKBH5) is reported to participate in infantile hemangioma (IH) progression. However, the underlying mechanism of ALKBH5 in IH remains unclear. Using qRT-PCR and Western blotting, ALKBH5, forkhead box F1 (FOXF1) and hexokinase 2 (HK-2) expressions in IH tissues and IH-derived endothelial cells XPTS-1 were assessed. The Me-RIP assay was used to analyze FOXF1 m6A level. CCK8, colony formation, flow cytometry and transwell assays were employed to determine IH cell viability, proliferation, apoptosis, migration and invasion. The interactions between YTH (YT521-B homology) domain 2 (YTHDF2), FOXF1 and HK-2 were analyzed by RIP, dual luciferase reporter gene assay and/or ChIP assay. The in vivo IH growth was evaluated in immunocompromised mice. FOXF1 was overexpressed in IH tissues, and its silencing inhibited IH cell proliferation, migration and invasion whereas promoting cell apoptosis in vitro. ALKBH5 upregulation facilitated FOXF1 mRNA stability and expression in IH cells in a m6A-YTHDF2-dependent manner. FOXF1 downregulation reversed the impact of ALKBH5 upregulation on IH cellular phenotypes. It also turned out that FOXF1 positively regulated HK-2 expression in IH cells through interacting with the HK-2 promoter. HK-2 upregulation abolished FOXF1 knockdown's inhibition on IH cell aggressive behaviors. ALKBH5 or FOXF1 silencing suppressed IH tumor development via HK-2 signaling in immunocompromised mice. ALKBH5 promoted FOXF1 expression m6A-YTHDF2 dependently, which in turn elevated HK-2 expression, thereby accelerating IH development.

3.
Environ Sci Technol ; 58(22): 9804-9814, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38771927

RESUMEN

Autotrophic denitrification utilizing iron sulfides as electron donors has been well studied, but the occurrence and mechanism of abiotic nitrate (NO3-) chemodenitrification by iron sulfides have not yet been thoroughly investigated. In this study, NO3- chemodenitrification by three types of iron sulfides (FeS, FeS2, and pyrrhotite) at pH 6.37 and ambient temperature of 30 °C was investigated. FeS chemically reduced NO3- to ammonium (NH4+), with a high reduction efficiency of 97.5% and NH4+ formation selectivity of 82.6%, but FeS2 and pyrrhotite did not reduce NO3- abiotically. Electrochemical Tafel characterization confirmed that the electron release rate from FeS was higher than that from FeS2 and pyrrhotite. Quenching experiments and density functional theory calculations further elucidated the heterogeneous chemodenitrification mechanism of NO3- by FeS. Fe(II) on the FeS surface was the primary site for NO3- reduction. FeS possessing sulfur vacancies can selectively adsorb oxygen atoms from NO3- and water molecules and promote water dissociation to form adsorbed hydrogen, thereby forming NH4+. Collectively, these findings suggest that the NO3- chemodenitrification by iron sulfides cannot be ignored, which has great implications for the nitrogen, sulfur, and iron cycles in soil and water ecosystems.


Asunto(s)
Compuestos de Amonio , Nitratos , Sulfuros , Nitratos/química , Compuestos de Amonio/química , Sulfuros/química , Hierro/química , Desnitrificación
4.
Phys Chem Chem Phys ; 26(21): 15494-15510, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38752432

RESUMEN

High-level ab initio calculations are conducted for studying the kinetics of three linear pentanol radicals generated through H-atom abstraction reactions. The species involved are optimized using the M06-2X/6-311++G(d,p) level of theory, while a relaxed scan at the M06-2X/6-31g level of theory with 10° increments is used for the hindrance potential for low-frequency torsional modes. Single-point energies for all stationary points are obtained through the QCISD(T) and MP2 methods in combination with cc-pVDZ, cc-pVTZ, and cc-pVQZ basis sets, which can be extrapolated to the complete basis set (CBS) limit. The rate constants and branching ratios for isomerization and decomposition reactions are computed over a temperature range of 250-2000 K and a pressure range of 0.01-100 atm. Isomerization reactions are dominant at low temperatures, while decomposition reactions are more dominant at high temperatures. The branching ratio of the isomerization reaction exhibits a slight decrease with increasing pressure, while the trend for decomposition reactions depends on the type of the breaking bond. Based on the calculations for five branched pentanol radicals in part I, kinetics of linear and branched pentanol radicals are compared in this work and the results reveal that, for the same kind of ß-scission reaction at similar positions of linear and branched pentanol radicals, the rate constants of branched ones are faster than those of linear ones at low temperatures. The hydroxyl group adjacent to the breaking bond can increase the ß-scission reaction rate constants, while the effect can be ignored when the hydroxyl group is not adjacent to the breaking bond. Moreover, compared to when the hydroxyl group is located in the middle of the carbon chain, its positioning at the chain's end yields a more noticeable impact on the products and rate constants of C-O bond and O-H bond ß-scission reactions. Besides, when incorporating calculated rate constants into the CRECK model, the updated mechanism shows a better performance for ignition delay times of 1-pentanol in the NTC range but exhibits lower reactivity at higher temperatures. The simulation of speciation profiles also shows better agreement with the experimental data obtained using a flow reactor.

5.
Phys Chem Chem Phys ; 26(25): 17631-17644, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38864351

RESUMEN

Reaction kinetics of hydrogen atom abstraction from six alkyl cyclohexanes, methyl cyclohexane (MCH), ethyl cyclohexane (ECH), n-propyl cyclohexane (nPCH), iso-propyl cyclohexane (iPCH), sec-butyl cyclohexane (sBCH) and iso-butyl cyclohexane (iBCH), by the H atom are systematically studied in this work. The M06-2X method combined with the 6-311++G(d,p) basis set is used to perform geometry optimization, frequency analysis and zero-point energy calculations for all species. The intrinsic reaction coordinate (IRC) calculations are performed to confirm the transition states connecting the reactants and products correctly. One-dimensional hindered rotors are used to treat the low frequency torsional models with potentials scanned at the M06-2X/6-31G level of theory. Electronic single-point energy calculations for all reactants, transition states, and products are performed at the QCISD(T)/CBS level of theory. High-pressure limiting rate constants of 39 reaction channels are obtained using conventional transition state theory with asymmetric Eckart tunneling corrections in the temperature range 298.15-2000 K. Reaction rate rules for H-atom abstraction by the H atom from alkyl cyclohexanes on primary, secondary and tertiary carbon sites on both the side chain and ring are provided. The obtained rate constants are given by the Arrhenius expression in the temperature range 500-2000 K, which can be used for the combustion kinetics model development for alkyl cyclohexanes.

6.
Phys Chem Chem Phys ; 26(29): 20022-20036, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39007185

RESUMEN

The chemical kinetic studies of hydrogen atom (H-atom) abstraction reactions by hydroperoxyl (HȮ2) radicals from five branched pentanol isomers, including 3-methyl-1-butanol, 2-methyl-1-butanol, 1,1-dimethyl-1-propanol, 1,2-dimethyl-1-propanol, and 2,2-dimethyl-1-propanol were investigated systematically through high-level ab initio calculations. Geometry optimization, frequency analysis, and zero-point energy (ZPE) corrections were performed for six reactants, twenty-three transition states (TSs), and twenty-four products at the M06-2X/6-311++G(d,p) level of theory. The intrinsic reaction coordinate calculation was performed at the same level of theory to confirm the transition state connection. The one-dimensional hindered rotor treatment for low-frequency torsional modes was also treated at the M06-2X/6-311++G(d,p) level of theory. The QCISD(T)/CBS level of theory was used to calculate the single-point energies for the species whose T1 diagnostic value was lower than 0.035. At the same time, the CASPT2/CBS level of theory was used to calculate the single-point energies for the channel in which the T1 diagnostic value of transition states was greater than 0.035. Rate constants for the H-atom abstraction reactions from the five branched pentanol isomers by HȮ2 radicals were calculated by using conventional transition state theory with asymmetric Eckart tunneling corrections in the temperature range of 500-2000 K. Rate constants and branching ratios for the title reactions and the rate rules for ten different H-atom abstraction types were investigated. Temperature-dependent thermochemistry properties for all reactants and products were calculated by the composite methods of G3/G4/CBS-QB3/CBS-APNO, which were in good agreement with the data available in the literature. Rate constants for the H-atom abstraction reactions by HȮ2 radical from branched pentanol isomers were investigated in this work as part I, and those for linear pentanol isomers will be analyzed in part II. All the calculated kinetics and thermochemistry data can be utilized in the model development for branched pentanol isomers oxidation.

7.
J Nanobiotechnology ; 22(1): 460, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090717

RESUMEN

BACKGROUND: Nanoplastics (NPs) are emerging pollutants that pose risks to living organisms. Recent findings have unveiled the reproductive harm caused by polystyrene nanoparticles (PS-NPs) in female animals, yet the intricate mechanism remains incompletely understood. Under this research, we investigated whether sustained exposure to PS-NPs at certain concentrations in vivo can enter oocytes through the zona pellucida or through other routes that affect female reproduction. RESULTS: We show that PS-NPs disrupted ovarian functions and decreased oocyte quality, which may be a contributing factor to lower female fertility in mice. RNA sequencing of mouse ovaries illustrated that the PI3K-AKT signaling pathway emerged as the predominant environmental information processing pathway responding to PS-NPs. Western blotting results of ovaries in vivo and cells in vitro showed that PS-NPs deactivated PI3K-AKT signaling pathway by down-regulating the expression of PI3K and reducing AKT phosphorylation at the protein level, PI3K-AKT signaling pathway which was accompanied by the activation of autophagy and apoptosis and the disruption of steroidogenesis in granulosa cells. Since PS-NPs penetrate granulosa cells but not oocytes, we examined whether PS-NPs indirectly affect oocyte quality through granulosa cells using a granulosa cell-oocyte coculture system. Preincubation of granulosa cells with PS-NPs causes granulosa cell dysfunction, resulting in a decrease in the quality of the cocultured oocytes that can be reversed by the addition of 17ß-estradiol. CONCLUSIONS: This study provides findings on how PS-NPs impact ovarian function and include transcriptome sequencing analysis of ovarian tissue. The study demonstrates that PS-NPs impair oocyte quality by altering the functioning of ovarian granulosa cells. Therefore, it is necessary to focus on the research on the effects of PS-NPs on female reproduction and the related methods that may mitigate their toxicity.


Asunto(s)
Células de la Granulosa , Nanopartículas , Oocitos , Poliestirenos , Transducción de Señal , Animales , Femenino , Ratones , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Fertilidad/efectos de los fármacos , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Nanopartículas/toxicidad , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Ovario/efectos de los fármacos , Ovario/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Poliestirenos/toxicidad , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos
8.
Artículo en Inglés | MEDLINE | ID: mdl-38910153

RESUMEN

PURPOSE: To validate the Graves ophthalmopathy quality of life (GO-QOL) questionnaire in screening DON and to construct an effective model. METHODS: A total of 194 GO patients were recruited and divided into DON and non-DON (mild and moderate-to-severe) groups. Eye examinations were performed, and quality of life was assessed by the GO-QOL questionnaire. The random forest, decision tree model, receiver operator characteristic (ROC) curve, accuracy and Brier score were determined by R software. RESULTS: In GO-QOL, age, best corrected visual acuity (BCVA), exophthalmos, CAS, severity, and Gorman score were found to be factors related to visual function scores. On the appearance scale, gender, duration of GO, BCVA, exophthalmos, CAS and severity of GO were relevant. Both the visual function scores and appearance scores were significantly lower in DON groups than in non-DON groups (33.18 ± 24.54 versus 81.26 ± 17.39, 60.08 ± 24.82 versus 76.14 ± 27.56). The sensitivity, specificity, and AUC of the visual function scores were 91.1%, 81.7% and 0.939, respectively Visual function scores were used to construct a decision tree model. The sensitivity, specificity, and AUC of the model were 92.9%, 88.0% and 0.941, respectively, with an accuracy of 89.7% and a Brier score of 0.024. CONCLUSIONS: Visual function scores were qualified as a screening method for DON, with a cutoff point of 58. A multifactorial screening model based on visual function scores was constructed.

9.
Ecotoxicol Environ Saf ; 273: 116121, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38402792

RESUMEN

In recent years, nanoplastics (NPs) and triclosan (TCS, a pharmaceutical and personal care product) have emerged as environmental pollution issues, and their combined presence has raised widespread concern regarding potential risks to organisms. However, the combined toxicity and mechanisms of NPs and TCS remain unclear. In this study, we investigated the toxic effects of polystyrene NPs and TCS and their mechanisms on KGN cells, a human ovarian granulosa cell line. We exposed KGN cells to NPs (150 µg/mL) and TCS (15 µM) alone or together for 24 hours. Co-exposure significantly reduced cell viability. Compared with exposure to NPs or TCS alone, co-exposure increased reactive oxygen species (ROS) production. Interestingly, co-exposure to NPs and TCS produced synergistic effects. We examined the activity of superoxide dismutase (SOD) and catalase (CAT), two antioxidant enzymes; it was significantly decreased after co-exposure. We also noted an increase in the lipid oxidation product malondialdehyde (MDA) after co-exposure. Furthermore, co-exposure to NPs and TCS had a more detrimental effect on mitochondrial function than the individual treatments. Co-exposure activated the NRF2-KEAP1-HO-1 antioxidant stress pathway. Surprisingly, the expression of SESTRIN2, an antioxidant protein, was inhibited by co-exposure treatments. Co-exposure to NPs and TCS significantly increased the autophagy-related proteins LC3B-II and LC3B-Ⅰ and decreased P62. Moreover, co-exposure enhanced CASPASE-3 expression and inhibited the BCL-2/BAX ratio. In summary, our study revealed the synergistic toxic effects of NPs and TCS in vitro exposure. Our findings provide insight into the toxic mechanisms associated with co-exposure to NPs and TCS to KGN cells by inducing oxidative stress, activations of the NRF2-KEAP1-HO-1 pathway, autophagy, and apoptosis.


Asunto(s)
Triclosán , Femenino , Humanos , Especies Reactivas de Oxígeno/metabolismo , Triclosán/toxicidad , Triclosán/metabolismo , Antioxidantes/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Microplásticos/metabolismo , Poliestirenos/toxicidad , Poliestirenos/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Células de la Granulosa/metabolismo
10.
Reprod Biol Endocrinol ; 21(1): 38, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37081483

RESUMEN

BACKGROUND: Ovarian aging is a process of decline in its reserve leading to ovary dysfunction and even reduced health quality in offspring. However, aging-related molecular pathways in the ovary remain obscure. Lysine succinylation (Ksuc), a newly post-translational modification (PTM), has been found to be broadly conserved in both eukaryotic and prokaryotic cells, and associated with multiple pathophysiological processes. There are no relevant reports revealing a link between the molecular mechanisms of ovarian aging and Ksuc. METHODS: The level of Ksuc in ovaries of aged and premature ovarian insufficiency (POI) mice were detected by immunoblotting and immunohistochemical. To further explore the role of Ksuc in ovarian aging, using in vitro mouse ovary tissue culture and an in vivo mouse model with changed Ksuc level. RESULTS: Increased Ksuc in ovaries of aged and POI mice and distribution of Ksuc in various types of mice ovarian cells and the high level of Ksuc in granulosa cells (GCs) were revealed. Histological assessments and hormone levels analyses showed that the high Ksuc level down-regulated the ovarian index and the anti-Müllerian hormone (AMH) and estrogen levels, and increased follicular atresia. Moreover, in the high Ksuc groups, the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) intensities and the expression of Cleaved-caspase-3 increased and the expression of B-cell lymphoma-2 (Bcl-2) decreased together with positively-expressed P21, an aging-related marker. These results suggest that ovarian aging is likely associated with alteration in Ksuc. CONCLUSION: The present study has identified Ksuc in mouse ovary and found that high Ksuc level most likely contributes to ovarian aging which is expected further investigation to provide new information for delaying physiological ovarian aging and treating pathological ovarian aging.


Asunto(s)
Lisina , Insuficiencia Ovárica Primaria , Humanos , Femenino , Ratones , Animales , Lisina/metabolismo , Atresia Folicular , Insuficiencia Ovárica Primaria/terapia , Envejecimiento
11.
BMC Cancer ; 23(1): 576, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37349711

RESUMEN

BACKGROUND: To the best of our knowledge, no previous studies have explored the relationship between visceral obesity and malnutrition. Therefore, this study has aimed to investigate the association between them in patients with rectal cancer. METHODS: Patients with rectal cancer who underwent proctectomy were included. Malnutrition was defined according to the Global Leadership Initiative on Malnutrition (GLIM). Visceral obesity was measured using computed tomography (CT). The patients were classified into four groups according to the presence of malnutrition or visceral obesity. Univariate and multivariate logistic regression analyses were performed to evaluate risk factors for postoperative complications. Univariate and multivariate cox regression analyses were performed to evaluate the risk factors for overall survival (OS) and cancer-specific survival (CSS). Kaplan-Meier survival curves and log-rank tests were performed for the four groups. RESULTS: This study enrolled 624 patients. 204 (32.7%) patients were included in the well-nourished non-visceral obesity (WN) group, 264 (42.3%) patients were included in the well-nourished visceral obesity (WO) group, 114 (18.3%) patients were included in the malnourished non-visceral obesity (MN) group, and 42 (6.7%) patients were included in the malnourished visceral obesity (MO) group. In the multivariate logistic regression analysis, the Charlson comorbidity index (CCI), MN, and MO were associated with postoperative complications. In the multivariate cox regression analysis, age, American Society of Anesthesiologists (ASA) score, tumor differentiation, tumor node metastasis (TNM), and MO were associated with worsened OS and CSS. CONCLUSIONS: This study demonstrated that the combination of visceral obesity and malnutrition resulted in higher postoperative complication and mortality rates and was a good indicator of poor prognosis in patients with rectal cancer.


Asunto(s)
Desnutrición , Proctectomía , Neoplasias del Recto , Humanos , Estudios Retrospectivos , Neoplasias del Recto/complicaciones , Neoplasias del Recto/cirugía , Proctectomía/efectos adversos , Proctectomía/métodos , Desnutrición/complicaciones , Desnutrición/epidemiología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Obesidad , Obesidad Abdominal/complicaciones , Evaluación Nutricional , Estado Nutricional
12.
Environ Sci Technol ; 57(2): 1177-1185, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36538289

RESUMEN

Photochemically generated reactive oxygen species (ROS) play numerous key roles in earth's surface biogeochemical processes and pollutant dynamics. ROS production has historically been linked to the photosensitization of natural organic matter. Here, we report the photochemical ROS production from three naturally abundant iron minerals. All investigated iron minerals are photoactive toward sunlight irradiation, with photogenerated currents linearly correlated with incident light intensity. Hydroxyl radicals (•OH) and hydrogen peroxide (H2O2) are identified as the major ROS species, with apparent quantum yields ranging from 1.4 × 10-8 to 3.9 × 10-8 and 5.8 × 10-8 to 2.5 × 10-6, respectively. Photochemical ROS production exhibits high wavelength dependence, for instance, the •OH quantum yield decreases with the increase of light wavelength from 375 to 425 nm, and above 425 nm it sharply decreases to zero. The temperature shows a positive impact on •OH production, with apparent activation energies ranging from 8.0 to 17.8 kJ/mol. Interestingly, natural iron minerals with impurities exhibit higher ROS production than their pure crystal counterparts. Compared with organic photosensitizers, iron minerals exhibit higher wavelength dependence, higher selectivity, lower efficiency, and long-term stability in photochemical ROS production. Our study highlights natural inorganic iron mineral photochemistry as a ubiquitous yet previously overlooked source of ROS.


Asunto(s)
Hierro , Luz Solar , Especies Reactivas de Oxígeno , Peróxido de Hidrógeno/química , Minerales
13.
Phys Chem Chem Phys ; 25(26): 17320-17336, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37345723

RESUMEN

Theoretical investigations on the kinetics of decomposition and isomerization reactions for five types of branched pentanol radicals are carried out in this work. The M06-2X/6-311++G(d,p) level of theory was used to optimize the geometries of all reactants, transition states, and products, while the hindrance potentials for the lower frequency modes in all of the species were obtained through a relaxed scan with an increment of 10° at the M06-2X/6-31G level of theory. Single-point energies of all species were determined at the QCISD(T)/cc-pVDZ, TZ level of theories with basis set corrections from MP2/cc-pVDZ, TZ, QZ methods. The RRKM/master equation was solved to calculate the pressure- and temperature-dependent rate coefficients for all channels in the pressure range of 0.01-100 atm over 250-2000 K. Pressure and temperature-dependent branching fractions of key species produced from pentanol radicals show that most of the pentanol radical isomers tend to isomerize to alkoxy radicals via a six-membered-ring or five-membered-ring transition state at low temperatures, producing ketones or aldehydes. At higher temperatures, the ß-scission reactions are the main reaction channels for the consumption of pentanol radicals. A weak pressure dependence has been found for all isomerization reactions, and it becomes more and more important as pressure increases. The pressure dependence trends are different for the ß-scission reactions of different branched pentanol radicals. In part I, the results for branched pentanol radical isomers are presented in detail, while in part II the results for linear pentanol radical isomers will be discussed.

14.
Phys Chem Chem Phys ; 25(15): 10795-10810, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-37010903

RESUMEN

Chemical kinetic studies of hydrogen atom abstraction reactions by hydroperoxyl (HȮ2) radical from six alkyl cyclohexanes of methyl cyclohexane (MCH), ethyl cyclohexane (ECH), n-propyl cyclohexane (nPCH), iso-propyl cyclohexane (iPCH), sec-butyl cyclohexane (sBCH), and iso-butyl cyclohexane (iBCH) are carried out systematically through high-level ab initio calculations. Geometry optimizations and frequency calculations for all species involved in the reactions are performed at the M06-2X/6-311++G(d,p) level of theory. Electronic single-point energy calculations are calculated at the UCCSD(T)-F12a/cc-pVDZ-F12 level of theory, with zero-point energy corrections. High-pressure limit rate constants for the reactions of alkyl cyclohexanes + HȮ2, in the temperature range of 500-2000 K, are calculated using conventional transition state theory taking asymmetric Eckart tunneling corrections and the one-dimensional hindered rotor approximation into consideration. Elementary reaction rate constants and branching ratios for each alkyl cyclohexane species were investigated, and rate constant rules of primary, secondary, and tertiary sites on the side-chain and the ring are provided here. Additionally, temperature-dependent thermochemical properties for reactants and products were also obtained in this work. The updated kinetics and thermochemistry data are used in the alkyl cyclohexane mechanisms to investigate their effects on ignition delay time predictions of shock tube and rapid compression machine data, and species concentrations from a jet-stirred reactor. It is found that these investigated reactions promote ignition delay times in the temperature range of 800-1200 K and also improve the prediction of cyclic olefin species formation which stems from the decomposition of fuel radicals.

15.
J Phys Chem A ; 127(8): 1960-1974, 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36802637

RESUMEN

The detailed kinetic properties of hydrogen atom abstraction by methylperoxy (CH3Ȯ2) radicals from alkanes, alkenes, dienes, alkynes, ethers, and ketones are systematically studied in this work. Geometry optimization, frequency analysis, and zero-point energy corrections were performed for all species at the M06-2X/6-311++G(d,p) level of theory. The intrinsic reaction coordinate calculation was consistently performed to ensure that the transition state connects the correct reactants and products, and one-dimensional hindered rotor scanning results were performed at the M06-2X/6-31G level of theory. The single-point energies of all reactants, transition states, and products were obtained at the QCISD(T)/CBS level of theory. High-pressure-limit rate constants of 61 reaction channels were calculated using conventional transition state theory with asymmetric Eckart tunneling corrections over the temperature range of 298.15-2000 K. Reaction rate rules for H atom abstraction by CH3Ȯ2 radicals from fuel molecules with different functional groups are constructed, which can be used in the development of combustion models of these fuels and fuel types. In addition, the influence of the functional groups on the internal rotation of the hindered rotor is also discussed.

16.
Bioorg Chem ; 131: 106317, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36525920

RESUMEN

Radioresistance represents a common phenomenon found in cancer treatment. Herein, the current study sought to evaluate the effects of a nanodrug delivery system of YSAYPDSVPMMS (YSA) peptide-modified gold nanoparticles-dextran-based hydrogel loaded with paclitaxel-succinic anhydride (P-Y/G@NHs) on non-small cell lung cancer (NSCLC) cell radiosensitivity. Firstly, utilizing the coupling reaction and layer-by-layer assembly technique, P-Y/G@NHs was prepared. The therapeutic effects of the P-Y/G@NHs in NSCLC cells in relation to the PI3K/AKT signaling pathway were examined by assessing the colony formation, apoptosis, and reactive oxygen species (ROS) generation of A549 cells under 10 Gy X-rays irradiation. Moreover, A549 tumor-bearing mice were generated to further validate the therapeutic effect in vivo. We confirmed the successful conjugation of the nanocomposite. Under 10 Gy X-rays irradiation, P-Y/G@NHs reduced the number of colonies of A549 cells, while inducing both cell apoptosis and ROS production. Moreover, P-Y/G@NHs enhanced the radiosensitivity of A549 cells by inhibiting the PI3K/AKT signaling pathway. In vivo fluorescence experiments validated that P-Y/G@NHs effectively-targeted and accumulated at the tumor site in nude mice, thus augmenting the radiosensitivity of tumors without significant immune toxicity or side effects. Conclusively, our findings highlighted that P-Y/G@NHs significantly enhanced the radiosensitivity of NSCLC cells by repressing the PI3K/AKT signaling pathway.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Nanopartículas del Metal , Animales , Ratones , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Ratones Desnudos , Especies Reactivas de Oxígeno/metabolismo , Oro/farmacología , Línea Celular Tumoral , Transducción de Señal , Apoptosis , Proliferación Celular
17.
Planta Med ; 89(15): 1468-1482, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37541437

RESUMEN

Boswellia is a traditional medicine for bruises and injuries. Its main active ingredient, acetyl-11-keto-beta-boswellic acid, has antioxidant and antiapoptotic effects. In this experiment, we used Sprague-Dawley rats to make a sciatic nerve injury model to detect the transcription factor NF-E2-related factor 2/heme oxygenase 1 signaling pathway and apoptosis, combined with clinical indicators, for testing whether acetyl-11-keto-beta-boswellic acid can reduce oxidative stress and promote sciatic nerve repair. Our results showed that acetyl-11-keto-beta-boswellic acid administration promoted myelin regeneration and functional recovery in the rat sciatic nerve, reduced lipid peroxidation levels, upregulated the expression of various antioxidant enzymes and enhanced enzyme activity, decreased the expression levels of apoptosis-related proteins, and promoted nuclear translocation of the transcription factor NF-E2-related factor 2 protein. In vitro studies revealed that acetyl-11-keto-beta-boswellic acid reduced H2O2-induced reactive oxygen species production, restored mitochondrial membrane potential, upregulated the expression of various antioxidant enzymes, and downregulated apoptosis-related indicators in Schwann cells, and these therapeutic effects of acetyl-11-keto-beta-boswellic acid were reversed after ML385 treatment in Schwann cells. In summary, acetyl-11-keto-beta-boswellic acid alleviates oxidative stress and apoptosis caused by sciatic nerve injury in rats by activating the transcription factor NF-E2-related factor 2/heme oxygenase 1 signaling pathway, promotes the recovery of sciatic nerve function in rats, and is a promising therapeutic agent to promote sciatic nerve repair by alleviating excessive oxidative stress.


Asunto(s)
Hemo-Oxigenasa 1 , Triterpenos , Ratas , Animales , Hemo-Oxigenasa 1/metabolismo , Hemo-Oxigenasa 1/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Ratas Sprague-Dawley , Antioxidantes/farmacología , Antioxidantes/metabolismo , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/farmacología , Estrés Oxidativo , Transducción de Señal , Triterpenos/farmacología , Triterpenos/uso terapéutico , Triterpenos/metabolismo , Nervio Ciático/metabolismo , Células de Schwann/metabolismo
18.
Clin Exp Ophthalmol ; 51(5): 453-461, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37084233

RESUMEN

BACKGROUND: Current modalities for diagnosing carotid cavernous fistula (CCF) are inaccurate in analysing retinal microcirculations and nerve fibre changes. Retinal microvascular and neural alterations occur in CCF patients and can be quantitatively measured using optical coherence tomography angiography (OCTA). We measured the neurovascular changes in the eyes of CCF patients and used OCTA as a supplementary method. METHODS: This cross-sectional study studied 54 eyes of 27 unilateral CCF subjects and 54 eyes of 27 healthy age- and sex-matched controls. OCTA parameters in the macula and optic nerve head (ONH) were analysed using a one-way analysis of variance with further Bonferroni corrections. Parameters with statistical significance were included in a multivariable binary logistic regression analysis and receiver operating characteristic (ROC) curves were generated. RESULTS: There was significantly less deep-vessel density (DVD) and ONH-associated capillary density in both eyes of CCF patients than in controls, while the differences between the affected and contralateral eyes were insignificant. The retinal nerve fibre layer and ganglion cell complex thickness were lower in the affected eyes than in the contralateral or controlled eyes. ROC curves identified DVD and ONH-associated capillary density as significant parameters in both eyes of CCF patients. CONCLUSION: The retinal microvascular circulation was affected in both eyes of unilateral CCF patients. Microvascular alterations occurred before retinal neural damage. This quantitative study suggests a supplementary measurement for diagnosing CCF and detecting early neurovascular impairments.


Asunto(s)
Fístula del Seno Cavernoso de la Carótida , Disco Óptico , Humanos , Tomografía de Coherencia Óptica/métodos , Fístula del Seno Cavernoso de la Carótida/diagnóstico , Estudios Transversales , Angiografía , Disco Óptico/irrigación sanguínea , Angiografía con Fluoresceína/métodos , Vasos Retinianos
19.
Ecotoxicol Environ Saf ; 257: 114941, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37087970

RESUMEN

Nanoplastics (NPs) have recently emerged in the context of global plastic pollution. They may be more toxic than macroplastics litter and microplastic fragments due to its abundances, tiny sizes, and cellular accessibility. The female reproductive toxicity of NPs has been widely documented for aquatic animals, but their effects and underlying mechanisms remain poorly understood in mammals. This study aimed to explore the effects of NPs on female reproduction using human ovarian granulosa cells (GCs) and female mice. The accumulation of polystyrene NPs (PS-NPs) in human granulosa-like tumor cells (KGN cells) and the ovaries of female Balb/c mice were evaluated by exposure to fluorescent PS-NPs. Proliferation and apoptosis, reactive oxygen species (ROS), and Hippo signaling pathway-related factors were analyzed in KGN cells. In addition, fertility rate, litter size, ovarian weight and microstructure, follicle development, serum level of anti-Mullerian hormone, and apoptosis in ovaries were examined in female mice. Here, the PS-NPs can penetrate the KGN cells and accumulate in the ovaries. In vitro, 100 µg/ml PS-NPs inhibited proliferation, induced apoptosis, accumulated ROS, activated three key regulators of the Hippo signaling pathway (MST1, LATS1, and YAP1), and downregulated the mRNA levels of CTGF and Cyr61 in KGN cells. Furthermore, salidroside, an antioxidative compound extracted from Rhodiola rosea, alleviated the damage of PS-NPs to KGN and inhibited the activation of the Hippo signal pathway. In vivo, exposure to 1 mg/day PS-NPs resulted in decreased fertility, abnormal ovarian function, and increased ovarian apoptosis in female mice. Overall, our data suggest that PS-NPs cause granulosa cell apoptosis and affect ovarian functions, leading to reduced fertility in female mice, by inducing oxidative stress and dysregulating the Hippo pathway.


Asunto(s)
Microplásticos , Poliestirenos , Humanos , Femenino , Animales , Ratones , Poliestirenos/metabolismo , Microplásticos/metabolismo , Ovario , Especies Reactivas de Oxígeno/metabolismo , Plásticos/metabolismo , Células de la Granulosa , Mamíferos
20.
Cancer Sci ; 113(4): 1417-1427, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35133063

RESUMEN

Resistance to irradiation (IR) remains a major therapeutic challenge in tumor radiotherapy. The development of novel tumor-specific radiosensitizers is crucial for effective radiotherapy against solid tumors. Here, we revealed that remodeling tumor tissue penetration via tumor-penetrating peptide internalizing arginine-glycine-aspartic acid RGD (iRGD) enhanced irradiation efficacy. The growth of 4T1 and CT26 multicellular tumor spheroids (MCTS) and tumors was delayed significantly by the treatment with IR and iRGD. Mechanistically, iRGD reduced hypoxia in MCTS and tumors, resulting in enhanced apoptosis after MCTS and tumors were treated with IR and iRGD. This is the first report that shows enhanced radiation efficacy by remodeling tumor-specific tissue penetration with iRGD, implying the potential clinical application of peptides in future tumor therapy.


Asunto(s)
Oligopéptidos , Hipoxia Tumoral , Apoptosis , Línea Celular Tumoral , Humanos , Oligopéptidos/uso terapéutico , Péptidos , Radioterapia
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