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1.
ACS Omega ; 9(22): 23688-23702, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38854565

RESUMEN

In China, both vanadium(V) and chromium(VI) are present in wastewater resulting from vanadate precipitation (AVP wastewater) and from leaching vanadium-chromium reduction slag. Addressing environmental preservation and the comprehensive utilization of metal resources necessitates the extraction and separation of V(V) and Cr(VI) from these mixed solutions. However, their separation is complicated by very similar physicochemical properties. This study establishes a method for the dynamic selective adsorption of V(V) from such mixtures. It evaluates the impact of various operating conditions in columns on dynamic adsorption behavior. This study examines the migration patterns of the mass transfer zone (MTZ) and forecasts its effective adsorption capacity through multivariate polynomial regression and a neural network (NN) model. The NN model's outcomes are notably more precise. Its analysis reveals that C 0 is the most critical factor, with Q and H following in importance. Furthermore, the dynamic properties were analyzed using two established models, Thomas and Klinkenberg, revealing that both intraparticle and liquid film diffusion influence the rates of exchange adsorption, with intraparticle diffusion being the more significant factor. Using 3 wt % sodium hydroxide as the eluent to elute V(V)-loaded resin at a flow rate of 4 mL/min resulted in a chromium concentration of less than 3 mg/L in the V(V) eluate, indicating high vanadium-chromium separation efficiency in this method. These findings offer theoretical insights and economic analysis data that are crucial for optimizing column operation processes.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 525-531, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-38660862

RESUMEN

OBJECTIVE: To explore the plasma metabolomic characteristics of children with transfusion-dependent thalassemia (TDT), and reveal the changes of metabolic pattern in children with TDT. METHODS: 23 children with TDT who received regular blood transfusion in Ganzhou Women and Children's Health Care Hospital in 2021 were selected, and 11 healthy children who underwent physical examination during the same period were selected as the control group. The routine indexes between children with TDT and the control group were compared, and then the metabolic composition of plasma samples from children with TDT and the control group was detected by liquid chromatography-mass spectrometry. An OPLS-DA model was established to perform differential analysis on the detected metabolites, and the differential metabolic pathways between the two groups were analyzed based on the differential metabolites. RESULTS: The results of routine testing showed that the indexes of ferritin, bilirubin, total bile acid, glucose and triglycerides in children with TDT were significantly higher than those in healthy controls, while hemoglobin and total cholesterol were significantly lower (all P <0.05). However there was no significant difference in lactate dehydrogenase between the two groups (P >0.05). Compared with the control group, 190 differential metabolites (VIP>1) were identified in TDT children. Among them, 168 compounds such as arginine, proline and glycocholic acid were significantly increased, while the other 22 compounds such as myristic acid, eleostearic acid, palmitic acid and linoleic acid were significantly decreased. The metabolic pathway analysis showed that the metabolic impact of TDT on children mainly focused on the upregulation of amino acid metabolism and downregulation of lipid metabolism. CONCLUSION: The amino acid and lipid metabolism in children with TDT were significantly changed compared with the healthy control group. This finding is helpful to optimize the treatment choice for children with TDT, and provides a new idea for clinical treatment.


Asunto(s)
Metaboloma , Talasemia , Humanos , Niño , Talasemia/terapia , Talasemia/sangre , Transfusión Sanguínea , Estudios de Casos y Controles , Plasma , Metabolómica , Triglicéridos/sangre , Femenino
3.
Pract Radiat Oncol ; 14(2): 81-82, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38431368
4.
ACS Omega ; 7(37): 33156-33166, 2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-36157726

RESUMEN

Since nonmetal (NM)-doped two-dimensional (2D) materials can effectively modulate their physical properties and chemical activities, they have received a lot of attention from researchers. Therefore, the stability, electronic properties, and electrocatalytic water splitting activity of precious-metal (PM)-adsorbed silicene doped with two NM atoms are investigated based on density functional theory (DFT) in this paper. The results show that NM doping can effectively improve the stability of PM-adsorbed silicene and exhibit rich electronic properties. Meanwhile, by comparing the free energies of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) intermediates of 15 more stable NM-doped systems, it can be concluded that the electrocatalytic water splitting activity of the NM-doped systems is more influenced by the temperature. Moreover, the Si-S2-Ir-doped system exhibits good HER performance when the temperature is 300 K, while the Si-N2-Pt-doped system shows excellent OER activity. Our theoretical study shows that NM doping can effectively promote the stability and electrocatalytic water splitting of PM-adsorbed silicene, which can help in the application of silicene in electrocatalytic water splitting.

5.
Transbound Emerg Dis ; 69(5): e3202-e3207, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35119777

RESUMEN

Porcine reproductive and respiratory syndrome virus (PRRSV) is an important pathogen that causes huge economic losses to the swine industry worldwide. Here, a novel variant of PRRSV strain named TJnh2021 was isolated from nursery piglets with morbidity rate (75%) and mortality rate (40%) in Tianjin Province of China in 2021. Phylogenetic and molecular evolutionary analyses revealed that TJnh2021 was highly similar to NADC34-like (lineage 1.5, isolated in North America in 2014) in the ORF1ab-ORF2 and ORF6-ORF7 coding regions, as well as to QYYZ-like (lineage 3, isolated in China in 2010) in the ORF3-ORF5, suggestive of a natural recombination event. Recombination analyses revealed that recombination events occurred in two interlineage recombination events between lineages 1.5 and 3, and two breakpoints in ORF2 (nt12196) and ORF5 (nt13628) (with reference to the VR-2332 strain). Animal experiments demonstrated that TJnh2021 caused mortality rates of 40% and exhibited higher pathogenicity in piglets compared to other lineage 1.5 strains reported in China. Taken altogether, NADC34-like PRRSV has undergone genetic exchange with Chinese local PRRSV strains and recombination might be responsible for the variations in pathogenicity and highlight the importance of surveillance of this lineage in China.


Asunto(s)
Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Enfermedades de los Porcinos , Animales , China/epidemiología , Variación Genética , Genoma Viral , Filogenia , Síndrome Respiratorio y de la Reproducción Porcina/epidemiología , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Recombinación Genética , Porcinos , Virulencia/genética
7.
RSC Adv ; 10(41): 24549-24554, 2020 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35516172

RESUMEN

In this study, methanofullerenes and 2',3'-dihydrofuran C60 derivatives were selectively synthesized in high yields via the reactions of C60 with ß-keto esters under mild conditions by controlling the addition sequence and molar ratio of iodine and base. The structures of the products were determined by spectroscopic characterization. Moreover, a possible reaction mechanism for the selective formation of fullerene derivatives was proposed.

8.
J Phys Condens Matter ; 32(3): 035501, 2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31585446

RESUMEN

Planar bismuthene grown on SiC substrate provides a promising candidate to engineer van der Waals double-layer (DL) made of two dimensional (2D) topological insulators. We perform systematical calculations in DL hydrogenated bismuthene (H-Bi) that can be used to simulate the experimentally grown planar bismuthene to explore realizable 2D topological insulator van der Waals DL. Two possible geometry configurations of AA- and AB-stacked DL H-Bi are investigated. Due to pseudo Jahn-Teller effect, AB-stacked DL H-Bi has a strong interlayer coupling interaction and shows buckled lattice. Particularly, both AA- and AB-stacked DL H-Bi are topologically trivial rather than topologically nontrivial. The physical origin of the trivial topology is clarified by analyzing orbital composition. We discuss how the electronic properties are modified by interlayer coupling, external strain, and metal atom intercalation. It is also found that, for AB-stacked DL H-Bi, metal atom intercalation gives rise to novel multiple Rashba splitting near the valence band top, which is expected to manipulate the same spin in different planar bismuthene layers. Our results present various and tunable electronic properties of van der Waals DL H-Bi and allow for probing into multiple Rashba effect in 2D inversion-asymmetric topological insulators.

9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 48(3): 427-430, 2017 May.
Artículo en Chino | MEDLINE | ID: mdl-28616919

RESUMEN

OBJECTIVES: To investigate the effects of early enteral immunonutrition on postoperative immune function and rehabilitation of gastric cancer patients with nutritional risk. METHODS: New hospitalized patients with gastric cancer were evaluated the nutrient status based on NRS 2002. The patients who scored between 3 to 5 points were randomized into two groups(30 cases for each group), and those in experimental group were given 7-d early postoperative enteral immune nutrition, those in control group were given normal nutrition. The immune indexes (CD3+, CD4+, CD8+ and CD4+/CD8+) and nutritional indexes(transferrin, pre-albumin, albumin) were measured before operation and at the 3rd and 7th day postoperatively. In addition, the first flatus time, gastrointestinal adverse reactions and complications, length of hospital stays were compared between the two groups. RESULTS: The level of CD4+/CD8+ and transferrin, pre-albumin, albumin in experimental group were significantly higher than those in control group at the third and seventh day postoperatively (P<0.05).Compared with the control group, the experimental group had shorter first flatus time after surgery, which were (63.5±7.3) h vs. (72.8±8.6 ) h respectively (P<0.05).There were no statistically difference on pneumonia, anastomosis leakage, severe abdominal distension, inflammatory bowel obstruction and total postoperative hospitalization time between the two groups (P>0.05). CONCLUSIONS: Early enteral immunonutrition can effectively promote the recovery of nutritional status and immune function in gastric cancer patients with nutrition risk.


Asunto(s)
Nutrición Enteral , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/terapia , Albúminas/análisis , Relación CD4-CD8 , Humanos , Tiempo de Internación , Estado Nutricional , Complicaciones Posoperatorias , Periodo Posoperatorio , Transferrina/análisis
10.
Biochem Biophys Res Commun ; 465(3): 575-9, 2015 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-26296469

RESUMEN

Nanog safeguards pluripotency in mouse embryonic stem cells (mESCs). Insight into the regulation of Nanog is important for a better understanding of the molecular mechanisms that control pluripotency of mESCs. In a silico analysis, we identify four GATA-1 putative binding sites in Nanog proximal promoter. The Nanog promoter activity can be significantly repressed by ectopic expression of GATA-1 evidenced by a promoter reporter assay. Mutation studies reveal that one of the four putative binding sites counts for GATA-1 repressing Nanog promoter activity. Direct binding of GATA-1 on Nanog proximal promoter is confirmed by electrophoretic mobility shift assay and chromatin immunoprecipitation. Our data provide new insights into the expanded regulatory circuitry that coordinates Nanog expression.


Asunto(s)
Factor de Transcripción GATA1/metabolismo , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas de Homeodominio/metabolismo , Animales , Línea Celular , Factor de Transcripción GATA1/genética , Proteínas de Homeodominio/genética , Ratones , Células Madre Embrionarias de Ratones , Proteína Homeótica Nanog , Regiones Promotoras Genéticas/genética
11.
Biochem Biophys Res Commun ; 464(3): 936-42, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26188092

RESUMEN

Hesx1, a homeobox gene expressed in embryonic stem cells (ESCs), has been implicated in the core transcription factors governing the pluripotent state. However, data about the underlying mechanism of how Hesx1 is involved in maintaining pluripotency is still scarce. In this study, we find Hesx1 responds to multiple pluripotency-related pathway inhibitors as well as LIF stimulation. Particularly, the expression of Hesx1 can be readily induced by dual inhibition (2i) of glycogen synthase kinase 3 and mitogen-activated protein kinase. Forced expression of Hesx1 can partially compensate for the withdrawal of either LIF or each component of 2i. We also demonstrate that LIF and each inhibitor of 2i can induce Hesx1 independent of one another. We tentatively put forward that Hesx1 is a common downstream target of LIF- and 2i-mediated self-renewal signaling pathways and plays an important role in maintaining ESC identity. Our study extends the methods of identifying the missing crucial factors in establishing ESC pluripotency.


Asunto(s)
Células Madre Embrionarias/metabolismo , Proteínas de Homeodominio/metabolismo , Células Madre Pluripotentes/fisiología , Proteínas Represoras/metabolismo , Animales , Diferenciación Celular/genética , Células Cultivadas , Células Madre Embrionarias/citología , Células Madre Embrionarias/efectos de los fármacos , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3/metabolismo , Proteínas de Homeodominio/genética , Factor Inhibidor de Leucemia/farmacología , Ratones Transgénicos , Proteína Homeótica Nanog , Factor 3 de Transcripción de Unión a Octámeros/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Proteínas Represoras/genética , Factores de Transcripción SOXB1/genética , Transducción de Señal , Tretinoina/farmacología
12.
Science ; 334(6061): 1367-72, 2011 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-22096103

RESUMEN

The end-Permian mass extinction was the most severe biodiversity crisis in Earth history. To better constrain the timing, and ultimately the causes of this event, we collected a suite of geochronologic, isotopic, and biostratigraphic data on several well-preserved sedimentary sections in South China. High-precision U-Pb dating reveals that the extinction peak occurred just before 252.28 ± 0.08 million years ago, after a decline of 2 per mil (‰) in δ(13)C over 90,000 years, and coincided with a δ(13)C excursion of -5‰ that is estimated to have lasted ≤20,000 years. The extinction interval was less than 200,000 years and synchronous in marine and terrestrial realms; associated charcoal-rich and soot-bearing layers indicate widespread wildfires on land. A massive release of thermogenic carbon dioxide and/or methane may have caused the catastrophic extinction.


Asunto(s)
Biodiversidad , Ecosistema , Extinción Biológica , Fósiles , Animales , Dióxido de Carbono , Isótopos de Carbono , China , Incendios , Sedimentos Geológicos , Invertebrados/clasificación , Isótopos , Plomo , Espectrometría de Masas , Metano , Océanos y Mares , Plantas/clasificación , Técnica de Dilución de Radioisótopos , Datación Radiométrica , Agua de Mar/química , Tiempo , Uranio , Vertebrados/clasificación
14.
Chin Med Sci J ; 20(2): 77-82, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16075742

RESUMEN

OBJECTIVE: To analyze the trends of case detection and other indicators of leprosy in China during 1985-2002. METHODS: Data reported by each province were collected by China National Leprosy Database in Nanjing P.R. China. All data about registered cases were put into computer for analysis. RESULTS: From 1985 to 2002, a total of 49,477 new leprosy cases had been detected. Among them, 69.5% were multibacillary cases and 25.4% had grade 2 disability. The child cases aged below 15 years accounted for 3.74% of total cases. Totally, 5824 cases and 303 cases relapsed after dapsone (DDS) mono-therapy and multidrug therapy (MDT), respectively. Case detection showed a marked reduction from 0.47/100,000 in 1985 to 0.18/100,000 in 1993 although there were several spurts due to operational factors. From 1994, case detection showed no significant decline. The grade 2 disability among new patients decreased from 31.4% in 1985 to 23.4% in 2002. The child case detection rate among new cases fluctuated between 2.70%-3.56% from 1999 to 2002. The incidence of relapse declined after the introduction of DDS mono-therapy. However, it increased after the introduction of MDT. CONCLUSION: China experiences in leprosy control show that it will take a long time with continuing present leprosy control activities to bring down the case detection and other indicators to a very low level even after reaching the elimination goal of leprosy.


Asunto(s)
Control de Enfermedades Transmisibles , Evaluación de la Discapacidad , Lepra/epidemiología , Adolescente , Adulto , Factores de Edad , Niño , China/epidemiología , Control de Enfermedades Transmisibles/tendencias , Dapsona/administración & dosificación , Dapsona/uso terapéutico , Quimioterapia Combinada , Humanos , Incidencia , Leprostáticos/administración & dosificación , Leprostáticos/uso terapéutico , Lepra/tratamiento farmacológico , Lepra/prevención & control , Recurrencia
15.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 22(3): 320-3, 2005 Jun.
Artículo en Chino | MEDLINE | ID: mdl-15952126

RESUMEN

OBJECTIVE: To assess the association between polymorphisms within the interferon-Gamma receptor gene(IFN-GammaR) and systemic lupus erythematosus (SLE) in Chinese people. METHODS: The IFN-GammaR genotypes of 94 SLE patients and 80 healthy subjects were examined by the reverse transcription-polymerase chain reaction (RT-PCR)-single-strand conformation polymorphism (SSCP) method, RT-PCR-restriction fragment length polymorphism (RFLP) method and DNA sequencing. RESULTS: There was no statistically significant difference in the IFN-GammaR genotype frequencies between the two groups. The IFN-Gamma R2 Arg64/Arg64 genotype decreased the risk of SLE (OR = 2.481, 95% CI 0.992 - 6.203, P = 0.047). The decreased risk of the development of SLE was detected in the individuals who had the combination of IFN-GammaR2 Arg64/Arg64 genotype and IFN-GammaR1 Val14/Val14 genotype (OR = 2.481, 95% CI 0.992 - 6.203, P = 0.047). CONCLUSION: The IFN-GammaR2 Arg64/Arg64 genotype does not determine susceptibility to SLE in Chinese people, and the combination of IFN-Gamma R2 Arg64/Arg64 genotype and IFN-Gamma R1 Val14/Val14 genotype does not, either.


Asunto(s)
Lupus Eritematoso Sistémico/genética , Polimorfismo Genético/genética , Receptores de Interferón/genética , Adolescente , Adulto , Secuencia de Bases , Femenino , Predisposición Genética a la Enfermedad/genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Conformacional Retorcido-Simple , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Receptor de Interferón gamma
16.
Ai Zheng ; 24(2): 194-8, 2005 Feb.
Artículo en Chino | MEDLINE | ID: mdl-15694032

RESUMEN

BACKGROUND & OBJECTIVE: Treating metastatic vertebral tumor is a common difficulty. Conservative treatment can't efficiently release the pain, and establish the spinal column; while operation may destroy normal tissue, and cause many complications, which would prolong the time of in-hospital, and delay the treatment of primary disease, at the same time, operation is not suitable for multiple metastatic spinal tumors. This study was designed to investigate the efficacy of percutaneous vertebroplasty (PVP) on metastatic spinal tumor under the guidance of digital subtraction angiography (DSA). METHODS: A total of 58 patients with metastatic spinal tumor were divided into 2 groups according to their intention, 28 (group A) were treated with PVP combined radiochemotherapy, 30 (group B) were treated with routine radiochemotherapy. Baselines of the 2 groups have no significant difference. Two months after treatment, the life quality, therapeutic response, stabilization of the vertebral column, and toxic effect were compared between group A and group B. RESULTS: After treatment, both groups showed significant changes in life quality, and therapeutic response (P < 0.05, t(1)=2.74, t(2)=11.74). Group A showed no complication. Group B showed 5 cases of pathologic constrictive fracture in spinal body. CONCLUSION: PVP is a simple and minimally invasive treatment with few complications, which can release pain, decrease incidence of pathologic constrictive fracture in spinal body, and improve life quality of patients with metastatic spinal tumor.


Asunto(s)
Vértebras Lumbares/cirugía , Procedimientos Ortopédicos/métodos , Neoplasias de la Columna Vertebral/secundario , Neoplasias de la Columna Vertebral/cirugía , Vértebras Torácicas/cirugía , Anciano , Dolor de Espalda/etiología , Dolor de Espalda/terapia , Cementos para Huesos/uso terapéutico , Neoplasias de la Mama/patología , Neoplasias del Colon/patología , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Calidad de Vida , Neoplasias de la Columna Vertebral/terapia , Resultado del Tratamiento
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