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1.
Phys Chem Chem Phys ; 26(30): 20167-20215, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39028293

RESUMEN

Amines, a class of prototypical volatile organic compounds, have garnered considerable interest within the context of atmospheric and combustion chemistry due to their substantial contributions to the formation of hazardous pollutants in the atmosphere. In the current energy landscape, the implementation of carbon-neutral energy and strategic initiatives leads to generation of new amine sources that cannot be overlooked in terms of the emission scale. To reduce the emission level of amines from their sources and mitigate their impact on the formation of harmful substances, a comprehensive understanding of the fundamental reaction kinetics during the degeneration process of amines is imperative. This perspective article first presents an overview of both traditional amine sources and emerging amine sources within the context of carbon peaking and carbon neutrality and then highlights the importance of H-abstraction reactions in understanding the atmospheric and combustion chemistry of amines from the perspective of reaction kinetics. Subsequently, the current experimental and theoretical techniques for investigating the H-abstraction reactions of amines are introduced, and a concise summary of research endeavors made in this field over the past few decades is provided. In order to provide accurate kinetic parameters of the H-abstraction reactions of amines, advanced kinetic calculations are performed using the multi-path canonical variational theory combined with the small-curvature tunneling and specific-reaction parameter methods. By comparing with the literature data, current kinetic calculations are comprehensively evaluated, and these validated data are valuable for the development of the reaction mechanism of amines.

2.
J Phys Chem A ; 128(11): 2191-2199, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38456900

RESUMEN

Barrierless bond dissociation reactions play an important role in fuel combustion. In this work, the pressure-dependent dissociation rate constants of ethylamine (EA) are accurately determined using variable-reaction-coordinate variational transition-state theory combined with the system-specific quantum Rice-Ramsperger-Kassel method. Before the kinetics calculations, the performances of four density functional theory methods in describing the bond dissociation of EA are evaluated against the benchmark method, FIC-MRCISD(T)+Q/cc-pVTZ, and the MN15-L/cc-pVTZ method is the best choice. By comparison of the Gibbs free energies and the rate constants for the bond dissociation reactions of EA, ethanol, and propane, the influence of functional groups on the reaction kinetics is discussed. The kinetics calculations show that the dissociation rate constants of EA are sensitive to pressure at low pressures and high temperatures, and the dominant channel is the reaction that yields C2H5 and NH2 radicals. A literature combustion model of EA is updated with our calculations, and the satisfactory agreement between the model predictions and reported ignition delay times of EA suggests the reliability of our calculations.

3.
Public Health ; 228: 92-99, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38340507

RESUMEN

OBJECTIVES: To investigate the independent impacts of adverse childhood experiences (ACEs) and positive childhood experiences (PCEs) on the health-related quality of life (HRQOL) of Chinese adolescents, and to explore the potential moderating role of PCEs in the association between ACEs and HRQOL. STUDY DESIGN: This was a cross-sectional study. METHODS: We surveyed 6982 students aged 11-20 in Guangzhou, China, from November to December 2021. Adolescents self-reported their ACEs, PCEs, and HRQOL by the Childhood Trauma Questionnaire Short Form, the Adverse Childhood Experiences-International Questionnaire, the Benevolent Childhood Experiences Scale, and the Paediatric Quality of Life Inventory Version 4.0, respectively. Multivariable linear regressions were performed to examine the associations between ACEs, PCEs, and HRQOL controlled for adolescents' age, gender, single-child status, boarding school attendance, primary caregivers, as well as parental age and occupational status. Likelihood-ratio tests were further applied to explore the moderating role of PCEs. RESULTS: In the models that considered both ACEs and PCEs, ACEs were significantly associated with lower HRQOL scores in all dimensions, summary scales, and total scale (ß = -13.88, 95% confidence interval [CI]: -14.82, -12.94 for total scale). Conversely, exposure to an above-average number of PCEs was associated with higher HRQOL scores in all measured aspects (ß = 7.20, 95%CI: 6.57, 7.84 for total scale). PCEs significantly moderated the association between ACEs and all HRQOL dimensions, summary scales, and total scale, except school functioning. CONCLUSION: ACEs and PCEs exert independent and opposite impacts on adolescents' HRQOL. PCEs could mitigate the negative impacts of ACEs. Enhancing resilience, like PCEs, may contribute to improving the HRQOL among adolescents who have exposed to ACEs.


Asunto(s)
Identidad de Género , Pruebas Psicológicas , Calidad de Vida , Humanos , Adolescente , Estudios Transversales , Autoinforme
4.
Zhonghua Zhong Liu Za Zhi ; 46(2): 140-145, 2024 Feb 23.
Artículo en Zh | MEDLINE | ID: mdl-38418188

RESUMEN

Objectives: This study aims to explore the clinical significance of lateral pelvic sentinel lymph node biopsy (SLNB) using indocyanine green (ICG) fluorescence navigation in laparoscopic lateral pelvic lymph node dissection (LLND) and evaluate the accuracy and feasibility of this technique to predict the status of lateral pelvic lymph nodes (LPLNs). Methods: The clinical and pathological characteristics, surgical outcomes, lymph node findings and perioperative complications of 16 rectal cancer patients who underwent SLNB using ICG fluorescence navigation in laparoscopic LLND in the Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College during April 2017 and October 2022 were retrospectively collected and analyzed. The patients did not receive preoperative neoadjuvant radiotherapy and presented with LPLNs but without LPLN enlargement (MRI showed the maximum short axes of the LPLNs were ≥5 mm and <10 mm at first visit). Results: All 16 patients were successfully performed SLNB using ICG fluorescence navigation in laparoscopic LLND. Three patients underwent bilateral LLND and 13 patients underwent unilateral LLND. The lateral pelvic sentinel lymph nodes (SLNs) were clearly fluorescent before dissection in 14 patients and the detection rate of SLNs for these patients was 87.5%. Lateral pelvic SLN metastasis was diagnosed in 2 patients and negative results were found in 12 patients by frozen pathological examinations. Among the 14 patients in whom lateral pelvic SLNs were detected, the dissected lateral pelvic non-SLNs were all negative. All dissected LPLNs were negative in two patients without fluorescent lateral pelvic SLNs. The specificity, sensitivity, negative predictive value, and accuracy was 85.7%, 100%, 100%, and 100%, respectively. Conclusions: This study indicates that lateral pelvic SLNB using ICG fluorescence navigation shows promise as a safe and feasible procedure with good accuracy. This technique may replace preventive LLND for locally advanced lower rectal cancer.


Asunto(s)
Laparoscopía , Neoplasias del Recto , Ganglio Linfático Centinela , Humanos , Biopsia del Ganglio Linfático Centinela/métodos , Verde de Indocianina , Relevancia Clínica , Estudios Retrospectivos , Escisión del Ganglio Linfático , Ganglio Linfático Centinela/diagnóstico por imagen , Ganglio Linfático Centinela/cirugía , Ganglio Linfático Centinela/patología , Colorantes , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/cirugía , Ganglios Linfáticos/patología , Laparoscopía/métodos , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/cirugía , Neoplasias del Recto/patología
5.
Zhonghua Yi Xue Za Zhi ; 104(3): 218-221, 2024 Jan 16.
Artículo en Zh | MEDLINE | ID: mdl-38220448

RESUMEN

The clinical characteristics, auxiliary examinations, skin and neuropathological features of 7 patients who had reticular cyanosis with peripheral neuropathy from the Department of Neurology, Huashan Hospital, Fudan University from January 2019 to December 2022 were retrospectively analyzed. Among the 7 patients, 5 were female and 2 were male.The age of onset of peripheral neuropathy was (39.8±21.3) years and the disease duration of peripheral neuropathy was (2.7±2.3) years. Three patients had acute onset and 4 patients had chronic onset. All the patients had limb numbness, with limb weakness in 6 patients and pain in 5 cases. Neuroelectrophysiological examination revealed 1 case of mononeuropathy, 2 cases of polyneuropathy, 2 cases of peripheral neuropathy, and 2 cases of sensory neuron neuropathy. Skin biopsy was performed in 3 patients, which presented hyperplasia and expansion of blood vessels in the dermis with lymphocyte infiltration. Nerve biopsy was performed in 3 patients, indicating axonal damage. Reticular cyanosis with peripheral neuropathy characterizes with numbness and weakness of limbs, most of which were accompanied by pain. Electrophysiological changes are in various forms. The pathological changes are dominated by the damage of axonal.


Asunto(s)
Livedo Reticularis , Enfermedades del Sistema Nervioso Periférico , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Cianosis/complicaciones , Hipoestesia/complicaciones , Livedo Reticularis/complicaciones , Dolor , Estudios Retrospectivos
6.
Nan Fang Yi Ke Da Xue Xue Bao ; 44(2): 226-235, 2024 Feb 20.
Artículo en Zh | MEDLINE | ID: mdl-38501407

RESUMEN

OBJECTIVE: To investigate the protective effect of colchicine against myocardial ischemia-reperfusion injury (I/R) and explore the underlying mechanism. METHODS: H9C2 cells exposed to hypoxia/reoxygenation (H/R) were treated with 3 nmol/L colchicine, after which the changes in cell viability were assessed using MTT assay, and AMPK phosphorylation, the expressions of NOX4, NRF2, SOD2, BAX, Bcl-2, and cleaved caspase-3 were detected with Western blotting. Male C57BL/6 mice were randomized into sham operation, I/R, I/R+colchicine, and I/R+colchicine+dorsomorphin (DSMP) groups. After the treatments, myocardial expressions of p-AMPK/AMPK, 8-OHdG, cleaved caspase-3, mitochondrial BAX (Mito-BAX), and cytoplasmic cytochrome C (Cyt-Cyto C) were examined and cardiac functions, infarct area, ATP content, and serum levels of lactic dehydrogenase (LDH) and cardiac troponin T (cTnT) levels were assessed. RESULTS: In H9C2 cells, H/R exposure significantly reduced AMPK phosphorylation and expressions of NRF2, SOD2, and Bcl-2, lowered cell viability, and up-regulated the expressions of NOX4, BAX, and cleaved caspase-3 (P < 0.05), and these changes were obviously alleviated by colchicine treatment (P < 0.05). In the mouse models, myocardial I/R injury significantly reduced myocardial AMPK phosphorylation level, ATP content, and expressions of NRF2, SOD2 and Bcl-2, caused cardiac function impairment, enhanced NOX4, Mito-BAX, Cyt-Cyto C, BAX, 8-OHdG, and cleaved caspase-3 expressions, and increased infarct area and serum LDH and cTnT levels (P < 0.05). Colchicine treatment significantly reversed the damaging effects of I/R (P < 0.05), but its protective effects was obviously antagonized by DSMP (P < 0.05). CONCLUSION: Colchicine alleviates myocardial I/R injury and protects cardiac function in mice by reducing myocardial oxidative stress and apoptosis via activating AMPK.


Asunto(s)
Daño por Reperfusión Miocárdica , Ratones , Animales , Masculino , Daño por Reperfusión Miocárdica/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Miocitos Cardíacos , Caspasa 3/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Apoptosis , Infarto/complicaciones , Infarto/metabolismo , Adenosina Trifosfato/metabolismo
7.
J Dent Res ; : 220345241256286, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39101661

RESUMEN

Tooth development is a complex process orchestrated by intricate gene regulatory networks, involving both odontogenic epithelium and ectomesenchyme. Six1, a pivotal transcription factor (TF), is involved in the development of the lower incisor. However, its precise role during incisor development and the molecular mechanisms underpinning its regulatory functions remain poorly understood. This study employs Six1 deletion mouse models to elucidate the critical regulatory role of Six1 in governing dental mesenchyme development. By performing single-cell RNA sequencing, we constructed a comprehensive transcriptome atlas of tooth germ development from the bud to bell stage. Our analyses suggest that the dental follicle and the dental papilla (DP) are differentiated from dental ectomesenchyme (DEM) and identify the key TFs underlying these distinct states. Notably, we show that Dlx1, Dlx2, and Dlx5 (Dlx1/2/5) may function as the key TFs that promote the formation of DP. We further show that the deletion of Six1 perturbs dental mesenchyme development by impeding the transitions from DEM to DP states. Importantly, SIX1 directly binds to the promoters of Dlx1/2/5 to promote their co-expression, which subsequently leads to widespread epigenetic and transcriptional remodeling. In summary, our findings unveil Six1's indispensable role in incisor development, offering key insights into TF-driven regulatory networks that govern dental mesenchyme cell fate transitions during tooth development.

10.
Clin. transl. oncol. (Print) ; 24(7): 1347-1353, julio 2022.
Artículo en Inglés | IBECS (España) | ID: ibc-203833

RESUMEN

AimTo introduce a novel endo-luminal balloon-assisted drainage (EBAD) and compare postoperative complication rates between EBAD and diverting stoma (DS) groups.MethodsThe single center prospective non-random cohort study included a total of 163 patients in convenience patients with rectal cancer between January 2019 and January 2021. Out of 163 patients, 83 underwent DS and 80 EBAD. Primary endpoints were postoperative complication rate.ResultsThe total number of complications was 28 in the DS group vs. 22 in the EBAD group (P = 0.388). 18 patients (21.7%) in the DS group and 14 patients (17.5%) in the EBAD group developed postoperative complication (P = 0.501). There were no differences identified for anastomotic leak rates between the two groups (P = 0.677). The rate of the pelvic abscess was lower in the EBAD group (1/80, 1.3%) than in the DS group (4/83, 4.8%) but with no statistical significance (P = 0.386). Compared with the DS group, the median operative time was shorter in the EBAD group (225 vs. 173.5 min, P < 0.001). Regarding incomplete small bowel obstruction, a higher prevalence was observed in the DS group compared to the EBAD group (7.2% vs 2.5%, P = 0.301). 7 patients (11.3%) in the DS group developed a para-stomal hernia, while no patient suffered a catheter-related complication. The median postoperative hospital stay was shorter in the DS groups than in the EBAD group (7 vs 8 days, P = 0.009). The median residence time of endo-luminal balloon-assisted drainage was 5.41 days. The median average and total volume of drainage were 51.57 ml/day and 255 ml, respectively.ConclusionEBAD is feasible and safe with similar postoperative complications when compared with a DS. EBAD may replace DS after rectum resection.


Asunto(s)
Humanos , Anastomosis Quirúrgica , Drenaje/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Neoplasias del Recto/cirugía , Estudios Retrospectivos , Recto
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