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1.
Phys Rev Lett ; 131(18): 186903, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37977608

RESUMEN

We study THz-driven condensate dynamics in epitaxial thin films of MgB_{2}, a prototype two-band superconductor (SC) with weak interband coupling. The temperature and excitation density dependent dynamics follow the behavior predicted by the phenomenological bottleneck model for the single-gap SC, implying adiabatic coupling between the two condensates on the ps timescale. The amplitude of the THz-driven suppression of condensate density reveals an unexpected decrease in pair-breaking efficiency with increasing temperature-unlike in the case of optical excitation. The reduced pair-breaking efficiency of narrow-band THz pulses, displaying minimum near ≈0.7 T_{c}, is attributed to THz-driven, long-lived, nonthermal quasiparticle distribution, resulting in Eliashberg-type enhancement of superconductivity, competing with pair breaking.

2.
J Chem Phys ; 158(13): 134706, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37031119

RESUMEN

In recent years, perovskite solar cells (PSCs) have been attracting more and more attention. Although perovskite materials have high defect tolerance, defects remain the main factor that seriously affects the efficiency and stability of PSCs. Herein, the ionic liquid of 1-butyl, 3-methylimidazolium acetate ([BMIM][ACO]) was introduced into the SnO2/perovskite interface for the first time. Thanks to the dipoles formed by ILs spontaneously, the work function of SnO2 was reduced and the transport ability of carriers was improved as well. Moreover, the Lewis acidity and lone pair electrons of [BMIM][ACO] contribute to the passivation of I- defects, Pb2+ defects, or Pb-I anti site defects. In addition, the presence of dipoles will repel the approach of photogenerated holes and the reverse transport of electrons, reducing the recombination of defect sites through field-effect passivation. The solar cell with efficiency of 19.43% was obtained under such a dual passivation effect, and the best device maintained 75.21% of the initial efficiency after 80 h of continuous illumination.

3.
Genomics ; 114(6): 110518, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36347326

RESUMEN

The Muscovy duck (Cairina moschata) is an economically important poultry species, which is susceptible to fatty liver. Thus, the Muscovy duck may serve as an excellent candidate animal model of non-alcoholic fatty liver disease. However, the mechanisms underlying fatty liver development in this species are poorly understood. In this study, we report a chromosome-level genome assembly of the Muscovy duck, with a contig N50 of 11.8 Mb and scaffold N50 of 83.16 Mb. The susceptibility of Muscovy duck to fatty liver was mainly attributed to weak lipid catabolism capabilities (fatty acid ß-oxidation and lipolysis). Furthermore, conserved noncoding elements (CNEs) showing accelerated evolution contributed to fatty liver formation by down-regulating the expression of genes involved in hepatic lipid catabolism. We propose that the susceptibility of Muscovy duck to fatty liver is an evolutionary by-product. In conclusion, this study revealed the potential mechanisms underlying the susceptibility of Muscovy duck to fatty liver.


Asunto(s)
Hígado Graso , Humanos , Hígado Graso/genética , Hígado Graso/veterinaria , Cromosomas , Lípidos
4.
J Asian Nat Prod Res ; 25(7): 634-640, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36259349

RESUMEN

The methanol extract of the seeds of Khaya ivorensis afforded two new mexicanolide limonoids, ivorensines A and B (1 and 2), together with one known compound, ruageanin D (3). The structures of the isolated compounds were established based on 1 D and 2 D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated limonoids were tested in vitro for antimicrobial potentials against 5 pathogenic microorganisms. As a result, compounds 1-3 exhibited antimicrobial activity against the tested Gram negative bacteria at the minimum inhibitory concentration values less than 50 µg/ml.


Asunto(s)
Limoninas , Meliaceae , Limoninas/química , Estructura Molecular , Meliaceae/química , Semillas/química
5.
Angew Chem Int Ed Engl ; 62(26): e202303791, 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37102633

RESUMEN

Chemically recyclable, circular polymers continue to attract increasing attention, but rendering both catalysts for depolymerization and high-performance polymers recyclable is a more sustainable yet challenging goal. Here we introduce a dual catalyst/polymer recycling system in that recyclable inorganic phosphomolybdic acid catalyzes selective depolymerization of high-ceiling-temperature biodegradable poly(δ-valerolactone) in bulk phase, which, upon reaching suitable molecular weight, exhibits outstanding mechanical performance with a high tensile strength of ≈66.6 MPa, fracture strain of ≈904 %, and toughness of ≈308 MJ m-3 , and thus markedly outperforms commodity polyolefins, recovering its monomer in pure state and quantitative yield at only 100 °C. In sharp contrast, the uncatalyzed depolymerization not only requires a high temperature of >310 °C but is also low yielding and non-selective. Importantly, the recovered monomer can be repolymerized as is to reproduce the same polymer, thereby closing the circular loop, and the recycled catalyst can be reused repeatedly for depolymerization runs without loss of its catalytic activity and efficiency.


Asunto(s)
Poliésteres , Polímeros , Poliésteres/química , Polímeros/química , Polienos , Catálisis
6.
J Chem Phys ; 157(19): 194704, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36414458

RESUMEN

Black-phase formamidinium lead iodide (FAPbI3), with a narrow bandgap and high thermal stability, has emerged as an in-demand material for highly efficient perovskite solar cells (PSCs). In a two-step sequential deposition, the PbI2 film plays an important role in the formation of a perovskite film with desirable qualities. This paper explores using N-methyl-2-pyrrolidone (NMP), a strong Lewis base, and N,N-dimethylformamide (DMF) as a mixed precursor solvent (DMF/NMP) of PbI2 and reports on preparing PbI2 films with a porous morphology by thermal treatment. Porous PbI2 films ensure the diffusion and sufficient reaction of the formamidinium iodide solution to form a smooth perovskite film. In addition, a dynamic spin coating method is also introduced to improve the uniformity of the perovskite film. Both methods yield a pure α-phase FAPbI3 film immediately in the unannealed state, which is necessary for the perovskite film to maintain phase stability. Finally, PSCs with a power conversion efficiency of 21.20% (0.13 cm2) are fabricated and optimized. The unencapsulated PSCs retain 90% of the initial efficiency for 1000 hours in dry air and exhibit a good thermal stability when heated to 85 °C.

7.
Mutagenesis ; 36(4): 281-293, 2021 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-34132814

RESUMEN

Poly (ADP-ribose) polymerase-1 (PARP1), a DNA repair gene, is the crucial player in the maintenance of genome integrity. T2285C polymorphism in coding region of PARP1 has been reported to be associated with susceptibility to tumours. We explored the relationship and mechanism of T2285C polymorphism of PARP1 to its expression and activity along with risk and prognosis in non-small cell lung cancer (NSCLC). mRNA expression was measured using quantitative RT-PCR assay or collected from TCGA dataset. Protein expression was examined with immunoblotting assay. Genotypes were determined by PCR-RFLP and sequencing approaches. PARP1 activity was determined with enzyme activity assay. Regulation of SIRT7 to PARP1 was determined by overexpression and small interference experiment. Association of PARP1 T2285C polymorphism with NSCLC risk was evaluated via multiple logistic regression analysis. Comparison of treatment response and progression-free survival (PFS) of NSCLC patients among different genotypes or regimens was made by chi-square test. Results indicated that mRNA and protein expression of PARP1 dramatically increased in NSCLC tissues in comparison with paired para-carcinoma tissues (P < 0.05). TC/CC mutant genotypes were associated with markedly enhanced PARP1 mRNA level compared with TT genotype (P = 0.011). No significant difference was discovered in PARP1 protein expression among TT, TC or CC genotypes (P > 0.05). Subjects with variant allele C had higher risk of NSCLC in comparison with allele T carriers [odds ratio = 1.560; P = 0.000]. NSCLC patients carrying mutational TC or CC genotypes were correlated with unfavourable response to platinum-based chemotherapy (TT vs. TC vs. CC, P = 0.010), and shorter PFS compared with TT genotype (TT vs. TC vs. CC, P = 0.009). T2285C mutation of PARP1 resulted in the enhancement of its mRNA, but the decrease of enzyme activity in tumour cell. Overexpression of SIRT7 attenuated PARP1 expression and activity. These findings suggest the variant allele C of T2285C polymorphism of PARP1 linked to an increase of NSCLC risk, and unfavourable efficacy and prognosis of NSCLC patients with platinum-based chemotherapy, which might be associated with enhancement of its mRNA expression and the diminishment of activity. Identification of PARP1 T2285C polymorphism and mRNA expression may be the promising way for the individualised treatment of NSCLC.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/genética , Poli(ADP-Ribosa) Polimerasa-1/genética , Polimorfismo de Nucleótido Simple , Anciano , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/enzimología , Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Pronóstico , Riesgo , Sirtuinas
8.
J Cell Mol Med ; 24(24): 14426-14440, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33155438

RESUMEN

Human cytomegalovirus (HCMV) infection in the respiratory tract leads to pneumonitis in immunocompromised hosts without available vaccine. Considering cytomegalovirus (CMV) mainly invades through the respiratory tract, CMV-specific pulmonary mucosal vaccine development that provides a long-lasting protection against CMV challenge gains our attention. In this study, N-terminal domain of GP96 (GP96-NT) was used as a mucosal adjuvant to enhance the induction of pulmonary-resident CD8 T cells elicited by MCMV glycoprotein B (gB) vaccine. Mice were intranasally co-immunized with 50 µg pgB and equal amount of pGP96-NT vaccine 4 times at 2-week intervals, and then i.n. challenged with MCMV at 16 weeks after the last immunization. Compared with pgB immunization alone, co-immunization with pgB/pGP96-NT enhanced a long-lasting protection against MCMV pneumonitis by significantly improved pneumonitis pathology, enhanced bodyweight, reduced viral burdens and increased survival rate. Moreover, the increased CD8 T cells were observed in lung but not spleen from pgB/pGP96-NT co-immunized mice. The increments of pulmonary CD8 T cells might be mainly due to non-circulating pulmonary-resident CD8 T-cell subset expansion but not circulating CD8 T-cell populations that home to inflammation site upon MCMV challenge. Finally, the deterioration of MCMV pneumonitis by depletion of pulmonary site-specific CD8 T cells in mice that were pgB/pGP96-NT co-immunization might be a clue to interpret the non-circulating pulmonary-resident CD8 T subset expansion. These data might uncover a promising long-lasting prophylactic vaccine strategy against MCMV-induced pneumonitis.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/virología , Citomegalovirus/inmunología , Neumonía/inmunología , Neumonía/virología , Proteínas Virales/inmunología , Administración Intranasal , Animales , Linfocitos T CD8-positivos/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Femenino , Interacciones Huésped-Patógeno , Humanos , Inmunización , Memoria Inmunológica , Pulmón/inmunología , Pulmón/patología , Activación de Linfocitos/inmunología , Ratones , Plásmidos/genética , Bazo/inmunología , Bazo/patología , Vacunación , Vacunas de ADN/inmunología , Vacunas Virales/inmunología
9.
Pak J Pharm Sci ; 32(4): 1467-1475, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31608864

RESUMEN

Recently, several studies have demonstrated that reactive oxygen species are responsible for inducing multiple organ failure and septic shock. Particularly, mitochondrial dysfunction has been demonstrated in the pathogenesis of multiple organ dysfunction syndrome (MODS). In cytopathic hypoxia, impairment of mitochondrial oxidative phosphorylation decreases aerobic adenosine triphosphate (ATP) production and potentially induces MODS. Shen-Fu (SF) injections are widely used in the treatment of various diseases. SF exhibits cardiovascular protective effects. For example, it can stretch the coronary artery, stabilize blood pressure, regulate IRI, and improve the overall heart function. Clinical studies have demonstrated that SF injections have notable therapeutic effects on septic and hemorrhagic shocks. In the present study, the effects of SF injection on mitochondrial function in the intestinal epithelial cells of rats with endotoxemia were analyzed.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Endotoxemia/tratamiento farmacológico , Intestino Delgado/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Animales , Citocromos c/metabolismo , Citocinas/sangre , Medicamentos Herbarios Chinos/administración & dosificación , Endotoxemia/metabolismo , Endotoxemia/patología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Inyecciones Intravenosas , Intestino Delgado/patología , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/patología , Ratas Sprague-Dawley
10.
J Neurosci ; 37(17): 4508-4524, 2017 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-28348138

RESUMEN

Action potentials, taking place over milliseconds, are the basis of neural computation. However, the dynamics of excitability over longer, behaviorally relevant timescales remain underexplored. A recent experiment used long-term recordings from single neurons to reveal multiple timescale fluctuations in response to constant stimuli, along with more reliable responses to variable stimuli. Here, we demonstrate that this apparent paradox is resolved if neurons operate in a marginally stable dynamic regime, which we reveal using a novel inference method. Excitability in this regime is characterized by large fluctuations while retaining high sensitivity to external varying stimuli. A new model with a dynamic recovery timescale that interacts with excitability captures this dynamic regime and predicts the neurons' response with high accuracy. The model explains most experimental observations under several stimulus statistics. The compact structure of our model permits further exploration on the network level.SIGNIFICANCE STATEMENT Excitability is the basis for all neural computations and its long-term dynamics reveal a complex combination of many timescales. We discovered that neural excitability operates under a marginally stable regime in which the system is dominated by internal fluctuation while retaining high sensitivity to externally varying stimuli. We offer a novel approach to modeling excitability dynamics by assuming that the recovery timescale is itself a dynamic variable. Our model is able to capture a wide range of experimental phenomena using few parameters with significantly higher predictive power than previous models.


Asunto(s)
Potenciales de Acción/fisiología , Fenómenos Electrofisiológicos/fisiología , Neuronas/fisiología , Algoritmos , Humanos , Modelos Neurológicos , Red Nerviosa/fisiología , Dinámicas no Lineales
11.
Int J Gynecol Cancer ; 28(5): 903-914, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29561301

RESUMEN

BACKGROUND: Angiogenesis inhibitors showed activity in ovarian cancer, but preliminary data could not accurately reflect the survival benefit. We thus did a systematic review and meta-analysis of randomized controlled trials to reassess the efficacy and safety of angiogenesis inhibitors combined with chemotherapy for ovarian cancer. METHODS: We searched PubMed, EMBASE, Cochrane, and ClinicalTrials.gov for randomized controlled trials comparing angiogenesis inhibitors containing therapy with conventional chemotherapy alone or no further treatment. Our main outcomes were the progression-free survival (PFS), overall survival (OS), and common adverse events. RESULTS: Fifteen trials were included (N = 8721 participants). For newly diagnosed ovarian cancer, combination treatment with angiogenesis inhibitors and chemotherapy yielded a lower risk of disease progression (hazard ratio [HR], 0.83; 95% confidence interval (CI), 0.71-0.97) and no improved OS (HR, 0.95; 95% CI, 0.86-1.05). In the high-risk progression subgroup, the addition of bevacizumab significantly improved PFS (HR, 0.72; 95% CI, 0.65-0.81) and OS (HR, 0.84; 95%CI, 0.74-0.96). In recurrent patients, the combined HR was 0.58 (95% CI, 0.52-0.65) for PFS, and for OS, the combined HR was 0.86 (95% CI, 0.79-0.94). We found no significant improvement for either PFS (HR, 0.80; 95% CI, 0.63-1.01) or OS (HR, 1.06; 95% CI, 0.88-1.28) in the pure maintenance therapy.In the overall population, angiogenesis inhibitors increased the incidence of gastrointestinal perforation (risk ratio [RR], 2.57; 95% CI, 1.66-3.97), hypertension (RR, 7.60; 95% CI, 2.79-20.70), arterial thromboembolism (RR, 2.27; 95% CI, 1.34-3.84), proteinuria (RR, 4.31; 95% CI, 2.15-8.64), and complication of wound healing (RR, 1.72, 95% CI, 1.12-2.63). CONCLUSIONS: Combination treatment with angiogenesis inhibitors and chemotherapy significantly improved PFS and OS in both patients with high-risk of progression and recurrent ovarian cancer, with an increased incidence of common adverse events. Conversely, we detected no statistically significant survival benefit in the pure maintenance setting. The main limitation of the review is clinical heterogeneity across the studies.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Inhibidores de la Angiogénesis/efectos adversos , Femenino , Humanos , Neoplasias Ováricas/mortalidad , Ensayos Clínicos Controlados Aleatorios como Asunto
12.
Ecotoxicol Environ Saf ; 153: 84-90, 2018 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-29407743

RESUMEN

Surfactants are widely used in household and industrial products for cleaning and/or solubilization in our daily life. Therefore, they are finally discharged into wastewater treatment plants (WWTPs), which may be the major point pollution source for environment if they were not completely removed during wastewater treatment. In this study, two typical industrial and domestic WWTPs with different wastewater treatment technologies were considered for the topic. Totally, two types of surfactants were analyzed in 24 h influent and each processing unit effluent. Four linear alkylbenzene sulfonates (LASs) with the alkyl chain from C10 to C13, and two benzalkonium chlorides (BACs) with the alkyl chain of C12 and C14 were selected as target compounds. The total concentrations of LASs in influent varied from 19.2 to 1889 µg/L and LAS-C11 and LAS-C12 were the predominant compounds with the concentration from 6.01 to 641 µg/L and 8.02-674 µg/L, respectively. The total concentrations of BACs were much lower than those of LASs, with the concentration ranging from 0.00935 to 1.85 µg/L. Significant positive correlations were observed between concentrations of LASs and BACs in influent, indicating their same and/or similar sources. Compared with the concentration of influent, the concentration of effluent was much lower, indicating the high removal efficiency by the two wastewater treatment processes. Biological treatment unit and cyclic activated sludge system were the main treatment units for the removing of surfactants, which suggested that these two types of surfactants can be easily degraded under aerobic condition. Seasonal variation indicated that the removal efficiencies of surfactants in autumn were a little higher than those in winter. The results of this study provided new insights into the environmental fate of surfactants in wastewater treatment system.


Asunto(s)
Ácidos Alcanesulfónicos/análisis , Tensoactivos/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Aerobiosis , China , Estaciones del Año , Aguas del Alcantarillado/química
13.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 35(1): 74-77, 2018 Feb 10.
Artículo en Zh | MEDLINE | ID: mdl-29419865

RESUMEN

OBJECTIVE To screen for mutations in a Chinese pedigree affected with hypokalemic periodic paralysis. METHODS The proband and nine family members were enrolled for the analysis of CACNA1S and SCN4A gene mutations. Genomic DNA was extracted from peripheral blood samples. The coding regions of the two genes were amplified with PCR and subjected to Sanger sequencing. Potential impact of suspected mutations was predicted with Bioinformatics software. The mutations were also verified among 100 healthy controls. RESULTS The proband and 5 family members (including 5 males and 1 female) had presented with episodes of flaccid paralysis accompanied by low serum potassium. Genetic testing has identified a c.664C>T (p.Arg222Trp) mutation in the proband, which has been reported previously. The same mutation was identified in other 5 affected members from the family. No mutation of the CACNA1S gene was detected. CONCLUSION The c.664C>T mutation of the SCN4A gene probably underlies the hypokalemic periodic paralysis in this family. All patients from the family have shown a complete penetrance of the disease.


Asunto(s)
Pruebas Genéticas/métodos , Parálisis Periódica Hipopotasémica/genética , Mutación , Canal de Sodio Activado por Voltaje NAV1.4/genética , Adulto , Anciano , Pueblo Asiatico/genética , Secuencia de Bases , China , Análisis Mutacional de ADN , Femenino , Humanos , Parálisis Periódica Hipopotasémica/diagnóstico , Parálisis Periódica Hipopotasémica/etnología , Masculino , Persona de Mediana Edad , Linaje
14.
Apoptosis ; 22(4): 519-530, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28078537

RESUMEN

We have found that Fas/FasL-mediated "extrinsic" pathway promoted cell apoptosis induced by renal ischemic injury. This study is to elucidate the upstream mechanism regulating FasL-induced extrinsic pathway during renal ischemia/reperfusion. Results demonstrated that when SIRT2 was activated by renal ischemia/reperfusion, activated SIRT2 could bind to and deacetylate FOXO3a, promoting FOXO3a nuclear translocation which resulted in an increase of nuclear FOXO3a along with FasL expression and activation of caspase8 and caspase3, triggering cell apoptosis during renal ischemia/reperfusion. The administration of SIRT2 inhibitor AGK2 prior to renal ischemia decreased significantly the number of apoptotic renal tubular cells and alleviated ultrastructure injury. These results indicate that inhibition of FOXO3a deacetylation might be a promising therapeutic approach for renal ischemia /reperfusion injury.


Asunto(s)
Transporte Activo de Núcleo Celular/fisiología , Apoptosis/fisiología , Proteína Ligando Fas/fisiología , Proteína Forkhead Box O3/metabolismo , Isquemia/patología , Riñón/irrigación sanguínea , Daño por Reperfusión/patología , Sirtuina 2/fisiología , Acetilación , Animales , Núcleo Celular/metabolismo , Evaluación Preclínica de Medicamentos , Activación Enzimática , Furanos/farmacología , Isquemia/metabolismo , Riñón/patología , Masculino , Procesamiento Proteico-Postraduccional , Quinolinas/farmacología , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismo
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(10): 3163-8, 2016 Oct.
Artículo en Zh | MEDLINE | ID: mdl-30222263

RESUMEN

Two series of chalcogenide glasses in Ge-Sb-S ternary system were synthesized with melt-quenching method. The phycochemical properties and spectral characteristic of glasses with different content of Ge and Sb were obtained with a series of measurements, and the systematic analysis on the change of optical properties was conducted in terms of microstructure of glasses combined with the Raman spectra. With constraint theory based on mean coordination number (Z), we described the variation trend of network structure directly. It was found that as long as the value of Z reaches 2.6, new vibration peaks would be formed in the Raman spectra indicating the presence of threshold behavior as well as the change of the network structure of the Ge-Sb-S glasses which could be expressed in a specific varition in the number of metal bonds and the nonmetal bonds. The appearance of new functional groups in the network have changed the total bond energy of glasses, and then affected the energy band structure of glasses representing the corresponding threshold behavior of the value of optical band gap (Eopg).

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(6): 1741-5, 2015 Jun.
Artículo en Zh | MEDLINE | ID: mdl-26601401

RESUMEN

The main analysis error of pressed powder pellet of carbonate comes from particle-size effect and mineral effect. So in the article in order to eliminate the particle-size effect, the ultrafine pressed powder pellet sample preparation is used to the determination of multi-elements and carbon-dioxide in carbonate. To prepare the ultrafine powder the FRITSCH planetary Micro Mill machine and tungsten carbide media is utilized. To conquer the conglomeration during the process of grinding, the wet grinding is preferred. The surface morphology of the pellet is more smooth and neat, the Compton scatter effect is reduced with the decrease in particle size. The intensity of the spectral line is varied with the change of the particle size, generally the intensity of the spectral line is increased with the decrease in the particle size. But when the particle size of more than one component of the material is decreased, the intensity of the spectral line may increase for S, Si, Mg, or decrease for Ca, Al, Ti, K, which depend on the respective mass absorption coefficient . The change of the composition of the phase with milling is also researched. The incident depth of respective element is given from theoretical calculation. When the sample is grounded to the particle size of less than the penetration depth of all the analyte, the effect of the particle size on the intensity of the spectral line is much reduced. In the experiment, when grounded the sample to less than 8 µm(d95), the particle-size effect is much eliminated, with the correction method of theoretical α coefficient and the empirical coefficient, 14 major, minor and trace element in the carbonate can be determined accurately. And the precision of the method is much improved with RSD < 2%, except Na2O. Carbon is ultra-light element, the fluorescence yield is low and the interference is serious. With the manual multi-layer crystal PX4, coarse collimator, empirical correction, X-ray spectrometer can be used to determine the carbon dioxide in the carbonate quantitatively. The intensity of the carbon is increase with the times of the measurement and the time delay even the pellet is stored in the dessicator. So employing the latest pressed powder pellet is suggested.

17.
Mol Biol Rep ; 41(10): 6611-8, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25167853

RESUMEN

This study aims to evaluate the ischemic injury of the liver in a porcine model of cardiac death assessed by in vivo microdialysis. A porcine model of cardiac death was established by the suffocation method. Metabolic indicators were monitored using the microdialysis technique during warm ischemia time (WIT) and cold ischemia time (CIT). Pathological changes in ischemic-injured livers were observed by haematoxylin-eosin staining. The predictive values of biochemical parameters regarding the liver donor were evaluated by receiver operating characteristic curve analysis. All statistical analyses were conducted using the SPSS 18.0 software (SPSS Inc, Chicago, Illinois, USA). The degree of warm ischemic injury of the livers increased with prolonged WIT. Serum glucose, glycerol, pyruvate, lactic acid levels and lactate-to-pyruvate (L/P) ratio increased gradually during WIT. Results from Pearson correlation analyses indicated that serum lactate level and L/P ratio were positively associated with the degree of warm ischemic injury of the livers. The degree of cold ischemic injury of the livers gradually increased after 12 h CIT. Serum glucose, lactic acid and L/P ratio achieved a peak after 6-8 h of CIT, but gradually decreased with prolonged CIT. The peak of glycerol occurred after 8 h of CIT, while no changes were found with prolonged CIT. Serum pyruvate level exhibited an increasing trend after 12 h CIT. Our results confirmed that serum glucose and lactate levels were negatively correlated with cold ischemic injury of the liver. However, serum glycerol and pyruvate levels showed positive correlations with cold ischemic injury of the liver. The liver donor was unavailable after 30 min WIT and 24 h CIT. The cut-off value of serum lactate level for warm ischemic injury of the livers was 2.374 with a sensitivity (Sen) of 90 % and specificity (Spe) of 95 %; while the L/P radio was 0.026 (Sen = 80 %, Spe = 83 %). In addition, the cut-off values of serum glucose, lactate, glycerol and pyruvate levels for cold ischemic injury of the livers were 0.339 (Sen = 100 %, Spe = 77 %), 1.172 (Sen = 100 %, Spe = 61 %), 56.359 (Sen = 100 %, Spe = 65 %) and 0.020 (Sen = 100 %, Spe = 67 %), respectively. Our findings provide empirical evidences that serum glucose, lactate levels and L/P ratio may be good indicators for the degree of warm ischemic injury of the livers after cardiac death; while serum glucose, lactate, glycerol and pyruvate levels may be important in predicting cold ischemic injury.


Asunto(s)
Muerte , Isquemia , Hígado/irrigación sanguínea , Hígado/patología , Microdiálisis , Animales , Curva ROC , Porcinos , Temperatura , Factores de Tiempo
18.
Rev Clin Esp (Barc) ; 224(1): 17-23, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38142976

RESUMEN

BACKGROUND: Arteriosclerosis has been proven to be a risk factor for the development of heart failure and readmission. ePWV is a novel non-invasive and simple indicator of arterial stiffness, and this study aims to investigate its relationship with all-cause mortality rate in patients with heart failure. METHODS: This study is a cohort study that included 1272 patients with heart failure from NHANES data from 1999 to 2018. The ePWV was divided into three groups, and the cumulative mortality rate of heart failure patients was calculated using KM survival curves. The relationship between ePWV and all-cause mortality rate in heart failure patients was represented by a smoothed curve fitting. COX regression analysis was used to assess the association between ePWV and all-cause mortality rate in heart failure patients. RESULTS: The average age of the study population was 67.8 ± 12.6 years, with 862 males and 650 females. During the 12-month follow-up period, there were 790 cases of all-cause mortality. Cox regression analysis was used to validate the relationship between ePWV and all-cause mortality rate in patients with heart failure. Patients with higher levels of ePWV tended to have a higher all-cause mortality rate. After adjustment for multiple factors, an increase in ePWV was positively associated with all-cause mortality rate (HR = 1.17, 95% confidence interval (CI): (1.12, 1.22)). Compared to the lowest tertile, the multivariable-adjusted HR and 95% CI for the highest tertile of ePWV were 1.81 (95% CI: (1.45, 2.27)). Additionally, a smoothed curve fitting was used to observe the relationship between ePWV and mortality rate, where the curve demonstrated a positive correlation between ePWV and all-cause mortality rate. Furthermore, KM survival curves indicated that all-cause mortality rate increased with the increase in ePWV. Subgroup analysis suggested a correlation between ePWV and mortality rate. CONCLUSION: Our study shows that ePWV is positively associated with all-cause mortality in patients with heart failure.


Asunto(s)
Insuficiencia Cardíaca , Análisis de la Onda del Pulso , Masculino , Femenino , Humanos , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Encuestas Nutricionales , Factores de Riesgo
19.
CNS Neurosci Ther ; 30(1): e14362, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37469037

RESUMEN

AIMS: The basolateral amygdala (BLA) plays an integral role in anxiety disorders (such as post traumatic stress disorder) stem from dysregulated fear memory. The excitability of glutamatergic neurons in the BLA correlates with fear memory, and the afterhyperpolarization current (IAHP ) mediated by small-conductance calcium-activated potassium channel subtype 2 (SK2) dominates the excitability of glutamatergicneurons. This study aimed to explore the effect of MPP2 interacts with SK2 in the excitability of glutamatergic neurons in the BLA and the extinction of conditioned fear in mice. METHODS: Fear memory was analyzed via freezing percentage. Western blotting and fluorescence quantitative PCR were used to determine the expression of protein and mRNA respectively. Electrophysiology was employed to measure the excitability of glutamatergic neurons and IAHP . RESULTS: Fear conditioning decreased the levels of synaptic SK2 channels in the BLA, which were restored following fear extinction. Notably, reduced expression of synaptic SK2 channels in the BLA during fear conditioning was caused by the increased activity of protein kinase A (PKA), while increased levels of synaptic SK2 channels in the BLA during fear extinction were mediated by interactions with membrane-palmitoylated protein 2 (MPP2). CONCLUSIONS: Our results revealed that MPP2 interacts with the SK2 channels and rescues the excitability of glutamatergic neurons by increasing the expression of synaptic SK2 channels in the BLA to promote the normalization of anxiety disorders and provide a new direction for the treatment.


Asunto(s)
Complejo Nuclear Basolateral , Animales , Ratones , Complejo Nuclear Basolateral/fisiología , Fenómenos Electrofisiológicos , Extinción Psicológica/fisiología , Miedo/fisiología , Neuronas
20.
Poult Sci ; 103(3): 103376, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38228059

RESUMEN

Wenchang chicken, a prized local breed in Hainan Province of China renowned for its exceptional adaptability to tropical environments and good meat quality, is deeply favored by the public. However, an insufficient understanding of its population architecture and the unclear genetic basis that governs its typical attributes have posed challenges in the protection and breeding of this precious breed. To address these gaps, we conducted whole-genome resequencing on 200 Wenchang chicken samples derived from 10 distinct strains, and we gathered data on an array of 21 phenotype traits. Population genomics analysis unveiled distinctive population structures in Wenchang chickens, primarily attributed to strong artificial selection for different feather colors. Selection sweep analysis identified a group of candidate genes, including PCDH9, DPF3, CDIN1, and SUGCT, closely linked to adaptations that enhance resilience in tropical island habitats. Genome-wide association studies (GWAS) highlighted potential candidate genes associated with diverse feather color traits, encompassing TYR, RAB38, TRPM1, GABARAPL2, CDH1, ZMIZ1, LYST, MC1R, and SASH1. Through the comprehensive analysis of high-quality genomic and phenotypic data across diverse Wenchang chicken resource groups, this study unveils the intricate genetic backgrounds and population structures of Wenchang chickens. Additionally, it identifies multiple candidate genes linked to environmental adaptation, feather color variations, and production traits. These insights not only provide genetic reference for the purification and breeding of Wenchang chickens but also broaden our understanding of the genetic basis of phenotypic diversity in chickens.


Asunto(s)
Pollos , Estudio de Asociación del Genoma Completo , Animales , Pollos/genética , Estudio de Asociación del Genoma Completo/veterinaria , Genómica , Fenotipo , Serogrupo
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