Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Inorg Chem ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967129

RESUMO

The development and exploration of uranium decorporation agents with straightforward synthesis, high removal ability, and low toxicity are crucial guarantees for the safety of workers in the nuclear industry and the public. Herein, we report the use of traditional Chinese medicine licorice for uranium decorporation. Licorice has good adsorption performance and excellent selectivity for uranium in the simulated human environment. Glycyrrhizic acid (GL) has a high affinity for uranium (p(UO2) = 13.67) and will complex with uranium at the carbonyl site. Both licorice and GL exhibit lower cytotoxicity compared to the commercial clinical decorporation agent diethylenetriamine pentaacetate sodium salts (CaNa3-DTPA). Notably, at the cellular level, the uranium removal efficiency of GL is eight times higher than that of CaNa3-DTPA. Administration of GL by prophylactic intraperitoneal injection demonstrates that its uranium removal efficiency from kidneys and bones is 55.2 and 23.9%, while CaNa3-DTPA shows an insignificant effect. The density functional theory calculation of the bonding energy between GL and uranium demonstrates that GL exhibits a higher binding affinity (-2.01 vs -1.15 eV) to uranium compared to DTPA. These findings support the potential of licorice and its active ingredient, GL, as promising candidates for uranium decorporation agents.

2.
Sci Rep ; 14(1): 14918, 2024 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942820

RESUMO

Sporting experience plays a pivotal role in shaping exercise habits, with a mutually reinforcing relationship that enhances cognitive performance. The acknowledged plasticity of cognition driven by sports necessitates a comprehensive examination. Hence, this study delves into the dynamic intricacies of the prefrontal cortex, exploring the impact of orienteering experience on cognitive performance. Our findings contribute empirical evidence regarding the functional activation of specific brain regions bridging the nexus between experiential factors and cognitive capabilities. In this cross-sectional study, a cohort of forty-nine athletes was enrolled to meticulously examine behavioral variances and prefrontal cortex dynamics among orienteering athletes of varying experience levels across diverse non-specialized scenarios. These investigations involved the utilization of functional near-infrared spectroscopy (fNIRS) to detect alterations in oxygenated hemoglobin (HbO2). The high-experience expert group exhibited neurological efficiency, demonstrating significantly diminished brain activation in the dorsolateral prefrontal, left ventral lateral prefrontal, and right orbitofrontal regions compared to the low-experience group. Within the low-experience novice group, superior performance in the spatial memory task was observed compared to the mental rotation task, with consistently lower reaction times across all conditions compared to the high-experience group. Notably, cerebral blood oxygenation activation exhibited a significant reduction in the high-experience expert group compared to the low-experience novice group, irrespective of task type. The dorsolateral prefrontal lobe exhibited activation upon task onset, irrespective of experience level. Correct rates in the spatial memory task were consistently higher than those in the mental rotation task, while brain region activation was significantly greater during the mental rotation task than the spatial memory task." This study elucidates disparities in prefrontal cortex dynamics between highly seasoned experts and neophyte novices, showcasing a cognitive edge within the highly experienced cohort and a spatial memory advantage in the inexperienced group. Our findings contribute to the comprehension of the neural mechanisms that underlie the observed cognitive advantage and provide insights into the forebrain resources mobilized by orienteering experience during spatial cognitive tasks."


Assuntos
Cognição , Córtex Pré-Frontal , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Cognição/fisiologia , Masculino , Feminino , Estudos Transversais , Adulto , Adulto Jovem , Atletas , Mapeamento Encefálico/métodos , Oxiemoglobinas/metabolismo
3.
Inorg Chem ; 63(16): 7464-7472, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38598182

RESUMO

Uranium accumulation in the kidneys and bones following internal contamination results in severe damage, emphasizing the pressing need for the discovery of actinide decorporation agents with efficient removal of uranium and low toxicity. In this work, cinnamic acid (3-phenyl-2-propenoic acid, CD), a natural aromatic carboxylic acid, is investigated as a potential uranium decorporation ligand. CD demonstrates markedly lower cytotoxicity than that of diethylenetriaminepentaacetic acid (DTPA), an actinide decorporation agent approved by the FDA, and effectively removes approximately 44.5% of uranyl from NRK-52E cells. More importantly, the results of the prompt administration of the CD solution remove 48.2 and 27.3% of uranyl from the kidneys and femurs of mice, respectively. Assessments of serum renal function reveal the potential of CD to ameliorate uranyl-induced renal injury. Furthermore, the single crystal of CD and uranyl compound (C9H7O2)2·UO2 (denoted as UO2-CD) reveals the formation of uranyl dimers as secondary building units. Thermodynamic analysis of the solution shows that CD coordinates with uranyl to form a 2:1 molar ratio complex at a physiological pH of 7.4. Density functional theory (DFT) calculations further show that CD exhibits a significant 7-fold heightened affinity for uranyl binding in comparison to DTPA.


Assuntos
Cinamatos , Urânio , Cinamatos/química , Cinamatos/farmacologia , Animais , Ligantes , Camundongos , Urânio/química , Urânio/metabolismo , Urânio/toxicidade , Rim/efeitos dos fármacos , Rim/metabolismo , Linhagem Celular , Teoria da Densidade Funcional , Ratos , Estrutura Molecular , Sobrevivência Celular/efeitos dos fármacos , Quelantes/química , Quelantes/farmacologia , Quelantes/síntese química
4.
J Hazard Mater ; 460: 132356, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37633015

RESUMO

The development of inexpensive and efficient semiconductor catalysts for photo-assisted uranium extraction from seawater remains a huge challenge. Herein, we have successfully synthesized amidoxime-rich g-C3N4 (AO-C3N4) by simply amidoximing a cyano-rich precursor for photo-assisted uranium extraction from seawater. The amidoxime groups not only served as the U(VI) binding sites for efficient uranium adsorption, but also significantly improved the visible light absorption capacity and carrier separation efficiency via introducing defect energy level, resulting in the excellent photocatalytic activity for AO-C3N4 towards photo-assisted uranium extraction. In the process of photo-assisted uranium extraction, U(VI) was first adsorbed by the amidoxime groups on the AO-C3N4 and then reduced to U(IV), while (UO2)O2·2H2O and (UO2)O2·4H2O were further formed by the oxidation of U(IV) by superoxide radicals (·O2-). Moreover, the generated reactive oxygen species (ROS) under light endowed AO-C3N4 with outstanding antibacterial properties, preventing the limitation of uranium extraction capacity from marine biofouling.

5.
Inorg Chem ; 62(14): 5799-5809, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36974005

RESUMO

The capture of the radionuclides strontium and cesium is of great importance to the environment, human health, and the sustainable development of nuclear energy, and zirconium phosphate with excellent ion exchange capacity has potential application in this field. In this work, we organically granulated zirconium phosphate to induce the formation of composite bead materials (CA@ZrP) with a calcium-containing phase with selectivity for Sr2+ and Cs+ higher than that of pure ZrP in low-pH environments and competing ionic environments. The adsorption performance of the material was systematically investigated. It was concluded that the adsorption performance of CA@ZrP improved with an increase in temperature, and under the dynamic adsorption experimental conditions, the treatment capacity of CA@ZrP for Sr2+ and Cs+ reached 404.79 and 302.2 bed volumes, respectively. The systematic study and characterization showed that the generation of the calcium-containing phase [Ca0.55ZrH0.9(PO4)2] promoted the exchange of Ca2+ with Sr2+ and Cs+, thus improving the selectivity of the composite beads. The highly selective composite bead material can be prepared in batches and easily recycled, providing a new idea for practical engineering applications.

6.
Inorg Chem ; 62(11): 4705-4715, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36880867

RESUMO

The low efficient transfer of photogenerated electrons to an active catalytic site is a pivotal problem for the photoreduction of highly soluble hexavalent uranium [U(VI)] to low soluble tetravalent uranium [U(IV)]. Herein, we successfully synthesized a TiO2-x/1T-MoS2/reduced graphene oxide heterojunction (T2-xTMR) with dual charge-transfer channels by exploiting the difference in Fermi levels between the heterojunction interfaces, which induced multilevel separation of photogenerated carriers. Theoretical and experimental results demonstrate that the presence of the electron buffer layer promoted the efficient migration of photogenerated electrons between the dual charge-transfer channels, which achieved effective separation of photogenerated carriers in physical/spatial dimensions and significantly extended the lifetime of photogenerated electrons. The migration of photogenerated electrons to the active catalytic site after multilevel spatial separation enabled the T2-xTMR dual co-photocatalyst to remove 97.4% of the high concentration of U(VI) from the liquid-phase system within 80 min. This work provides a practical reference for utilizing multiple co-catalysts to accomplish directed spatial separation of photogenerated carriers.

7.
Medicine (Baltimore) ; 101(30): e29670, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35905251

RESUMO

RATIONALE: Midgut malrotation is a rare congenital abnormality resulting from failure of complete intestinal rotation and subsequent fixation during early fetal development. There appeared to be no obvious symptoms in most patients, and a few patients may exhibit symptoms similar to hyperemesis gravidarum, such as nausea and vomiting. Here, we present a case of midgut malrotation presenting as hyperemesis gravidarum. PATIENT CONCERNS: A 27-year-old woman with an intrauterine pregnancy of 27 + 6 weeks complained of severe nausea and vomiting for 2 weeks. DIAGNOSIS: Magnetic resonance imaging showed obvious dilatation in the proximal part of the duodenum and gastric cavity and the absence of a duodenal path dorsal to the superior mesenteric artery, which was diagnosed as midgut malrotation. INTERVENTIONS: Considering that the patient's vital signs were stable, without manifestation of peritonitis or the risks of surgery to the fetus, conservative treatment was adopted. Unfortunately, the fetus developed severe hydrocephalus at 32 weeks. The patient and her family decided to abandon the fetus, and a mid-trimester-induced abortion was performed. OUTCOMES: The related symptoms completely disappeared after delivery, and the relevant examination after discharge also confirmed the presence of midgut malrotation without gastrointestinal discomfort within 1 year after delivery. LESSONS: Midgut malrotation can be considered as a differential diagnosis of hyperemesis gravidarum. Conservative treatment under close monitoring is desirable in pregnant women diagnosed with midgut malrotation.


Assuntos
Anormalidades do Sistema Digestório , Hiperêmese Gravídica , Volvo Intestinal , Adulto , Anormalidades do Sistema Digestório/complicações , Anormalidades do Sistema Digestório/diagnóstico , Anormalidades do Sistema Digestório/cirurgia , Feminino , Humanos , Hiperêmese Gravídica/complicações , Hiperêmese Gravídica/diagnóstico , Volvo Intestinal/complicações , Volvo Intestinal/diagnóstico , Volvo Intestinal/cirurgia , Náusea/etiologia , Gravidez
8.
Inorg Chem ; 61(4): 2242-2250, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35025499

RESUMO

Not only a critical matter in the nuclear fuel cycle but uranium is also a global contaminant with both radioactive and chemical toxicity. Reducing soluble hexavalent uranium [U(VI)] to relatively nonimmigrated tetravalent uranium [U(IV)] by photocatalytic technologies is recognized as a highly promising strategy for avoiding environmental pollution and re-extracting uranium resources from nuclear wastewater. Herein, we have designed a heterojunction photocatalyst constructed from the carbon aerogels (CA) and the CdS nanoflowers with an S-vacancy (CA@CdS-SV). With the S-vacancy and heterojunction being synergized, the U(VI) removal rate exceeded 97% in 40 min without the addition of any sacrificial agents. As impacted by the synergistic effects of the S-vacancy and heterojunction, thermodynamics and kinetics revealed that photogenerated electrons were first captured via shallow traps generated by vacancies on CdS-SV and then transferred to the CA surfaces through the heterojunction to realize the spatial separation of carriers, thereby achieving a satisfactory performance. This work is considered to underpin the improvement of U(VI) immobilization by exploiting the synergistic effect of vacancy engineering and the Schottky heterojunction from the perspective of thermodynamics and kinetics.

9.
J Hazard Mater ; 422: 126912, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34416695

RESUMO

How to efficiently treat radioactive uranium-containing nuclear wastewater is one of the significant challenges to ensure the safety of nuclear technology and to avoid environmental pollution. Here we firstly prepare the metal-free 2D/2D C3N5/GO nanosheets, and customize a type-II heterojunction based on the band bending theory to achieve enhanced uranium extraction capacity via synergistic adsorption photoreduction engineering. The structure of C3N5 is explained by electron energy loss spectroscopy and synchrotron-based near-edge X-ray absorption fine structure. And C3N5 with larger π-conjugated structure expands the light response range to 747 nm, which is about 1.67 times that of C3N4. Further, we also use density functional theory to prove the existence of alternating energy levels so that photogenerated electrons could be continuously injected into the surface of GO to ensure the effective separation of electron-hole pairs and increase the material activity. The results show that the removal ratio of uranium by 2D/2D C3N5/GO heterojunction is achieved as high as 96.1% even at a low uranium concentration of 10 ppm, and reached 93.4% after exposure to gamma-ray. This work will lay a foundation for customizing the energy band structure of nonmetal-based 2D/2D nanohybrids and enriching uranium-containing wastewater through adsorption photoreduction engineering in the future.

10.
ACS Omega ; 6(43): 28538-28547, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34746549

RESUMO

Photocatalysts have been extensively used for hydrogen evolution or organic degradation. In this work, two different heterojunction types of composite photocatalysts, 1T-MoS2@TiO2 with Schottky heterojunction and 2H-MoS2@TiO2 with type-II heterojunction, are synthesized via hydrothermal synthesis. These two composite materials exhibit excellent photocatalytic activity toward the degradation of tannic acid, which is a typical organic in nuclear wastewater. At an optimal loading of 16% 1T-MoS2, the 1T-MoS2@TiO2 shows the highest degradation capacity of 98%, which is 3.2 times higher than that of pure TiO2. The degradation rate of 16% 1T-MoS2@TiO2 is much higher than that of 13% 2H-MoS2@TiO2. The enhanced photocatalytic activity might be attributed to the improved charge transfer according to the mechanism investigation, supported by the X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS) analyses. This work provides new opportunities for constructing highly efficient catalysts for nuclear waste disposal.

11.
Cell Biochem Biophys ; 70(2): 1421-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25005769

RESUMO

To investigate associations of single nucleotide polymorphisms (SNPs) rs2228314 of sterol regulatory element-binding protein-2 (SREBP-2) or rs11039155 of liver X receptor α (LXRα) with susceptibility to polycystic ovary syndrome (PCOS) in a Chinese Han population. SREBP-2 rs2228314 and LXRα rs11039155 polymorphisms were genotyped in patients with PCOS and age- and sex-matched PCOS-free controls from a Chinese Han population. A total of 605 patients with PCOS and 615 controls were recruited in this study. We found that GC and CC genotypes of rs2228314, and variant C, were associated with a significantly increased risk of PCOS. In addition, GA and AA genotypes of rs11039155, as well as variant A, were also associated with a significantly increased risk of PCOS. Our results showed that SREBP-2 rs2228314 G to C change and variant C genotype as well as LXRα rs11039155 G to A change and variant A may contribute to PCOS in Chinese Han population.


Assuntos
Povo Asiático/etnologia , Etnicidade/genética , Predisposição Genética para Doença/genética , Receptores Nucleares Órfãos/genética , Síndrome do Ovário Policístico/genética , Polimorfismo de Nucleotídeo Único , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Receptores X do Fígado , Masculino , Síndrome do Ovário Policístico/metabolismo
12.
Zhonghua Fu Chan Ke Za Zhi ; 45(11): 843-7, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21211284

RESUMO

OBJECTIVE: To study changes of glial fibrillary acidic protein (GFAP) expression and neural apoptosis in rat hippocampus and cortex of cesarean delivered offspring. METHODS: Thirty-eight pregnant SD rats were randomly allocated into 2 groups: 19 rats in vaginal delivery (VD) and 19 rats in cesarean section (CS). Forty-eight fetuses born by VD were kept intact, 40 fetuses were delivered by CS on day 21 of gestation. The fetal brain tissues were taken out on postnatal day 30 and 115, the expression profiles of GFAP in hippocampus and cortex were measured by immunohistochemical staining and western blot. Apoptotic cells were detected using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. RESULTS: (1) The expression profiles of GFAP: on postnatal day 115, the mean number of GFAP-immunoreactive astrocytes of hippocampus 29.7 ± 10.9 in VD group was significantly lower than 36.2 ± 2.8 in CS group (P < 0.05). The average GFAP-positive cells in the cortex of frontal lobe of 23.2 ± 4.6 in VD group was significantly lower than 36.8 ± 5.9 in CS group (P < 0.01). Likewise, on postnatal day 30, the mean number of GFAP-immunoreactive astrocytes of frontal cortex of 27.8 ± 6.0 in VD group was remarkably lower than 39.4 ± 4.5 in CS group (P < 0.01). The average GFAP-positive cells in the hippocampus of 31.5 ± 3.5 in VD group were not significantly lower than 37.2 ± 7.0 in CS group (P > 0.05). The expression of GFAP was detected in hippocampus and frontal cortex by western blot, however, there was no significant different expression of GFAP between VD group and CS group. (2) Neuronal apoptosis: TUNEL staining results indicated that, on postnatal day 115, fewer apoptotic cells scattered in offspring hippocampus subregion were only shown in CS group, never in VD group. No TUNEL positive staining cells were labeled in hippocampal subregion in VD group, therefore significantly lower than that of CS group (P < 0.05). CONCLUSIONS: There were different influences of cesarean section on GFAP expression in hippocampus or cortex in different developmental stage of offspring. Cesarean section might increase GFAP expression in the hippocampus and frontal cortex, even trigger neuronal apoptosis of hippocampus region.


Assuntos
Apoptose , Encéfalo/metabolismo , Cesárea/efeitos adversos , Proteína Glial Fibrilar Ácida/metabolismo , Animais , Astrócitos/metabolismo , Northern Blotting , Córtex Cerebral/metabolismo , Parto Obstétrico/métodos , Feminino , Hipocampo/metabolismo , Imuno-Histoquímica , Neurônios , Gravidez , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Regulação para Cima
13.
Zhonghua Fu Chan Ke Za Zhi ; 39(9): 609-11, 2004 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-15498189

RESUMO

OBJECTIVE: To elucidate the possible relationship between pregnancy-induced hypertension syndrome (PIH) and expression of vimentin, type IV collagen and fibronectin in human placenta. METHODS: Nineteen pregnant women (PIH group) and 15 normal pregnant women (control group) matched for age and gestation were recruited. The expression of vimentin, type IV collagen and fibronectin in the placenta of PIH patients and normal subjects was investigated using immunohistochemical perioxidase-antiperoxidase (PAP) staining technique combined with an analysis through a computer-aided microphotographic system and compared between the two groups. RESULTS: The average grey value difference (GVD) which indicated positive staining of vimentin was 30 +/- 7 in section images of the moderate and severe PIH group, significantly lower than that of normal control group, 42 +/- 6 and mild PIH group, 42 +/- 9 (P < 0.01). The average GVD of type IV collagen in moderate and severe PIH group was 70 +/- 6, significantly higher than 29 +/- 4 of control group and 30 +/- 5 of mild PIH group (P < 0.001). The average GVD of fibronectin in moderate and severe PIH group was 37 +/- 4, significantly higher than that in control group, 31 +/- 4 and mild PIH group, 32 +/- 6 (P < 0. 05). CONCLUSIONS: There is tight relationship between abnormal expression of placental vimentin, type IV collagen, fibronectin and pathogenesis of PIH. Furthermore, the severity of PIH is positively correlated with the abnormal expression levels of those proteins.


Assuntos
Colágeno Tipo IV/metabolismo , Fibronectinas/metabolismo , Hipertensão Induzida pela Gravidez/metabolismo , Placenta/metabolismo , Vimentina/metabolismo , Adulto , Endotélio Vascular/metabolismo , Feminino , Humanos , Hipertensão Induzida pela Gravidez/etiologia , Imuno-Histoquímica , Gravidez
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...