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1.
Artículo en Inglés | MEDLINE | ID: mdl-38847755

RESUMEN

Right-ventricular (RV) function is an important prognostic indicator for pulmonary arterial hypertension (PAH), a vasculopathy that primarily and disproportionally affects women with distinct pre- and post-menopausal clinical outcomes. However, most animal studies have overlooked the impact of sex and ovarian hormones on RV remodeling in PAH. Here, we combined invasive measurements of RV hemodynamics and morphology with computational models of RV biomechanics in sugen-hypoxia (SuHx) treated male, ovary-intact female, and ovariectomized female rats. Despite similar pressure overload levels, SuHx induced increases in end-diastolic elastance and passive myocardial stiffening, notably in male SuHx animals, corresponding to elevated diastolic intracellular calcium. Increases in end-systolic chamber elastance were largely explained by myocardial hypertrophy in male and ovary-intact female rats, whereas ovariectomized females exhibited contractility recruitment via calcium transient augmentation. Ovary-intact female rats primarily responded with hypertrophy, showing fewer myocardial mechanical alterations and less stiffening. These findings highlight sex-related RV remodeling differences in rats, affecting systolic and diastolic RV function in PAH.

2.
Water Sci Technol ; 89(5): 1179-1194, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38483492

RESUMEN

The study investigated the denitrification effect of the iron autotrophic denitrification process for removing nitrite under anaerobic conditions, utilizing sponge iron as the electron donor. When the C/N ratio equaled 1, defined as the ratio of chemical oxygen demand to total nitrogen (TN), and the influent nitrite nitrogen (NO2--N) was at 80 mg/L, the average steady-state TN effluent concentration of this system was 41.94 mg/L during the 79-day experiment. The TN value exhibited a significant decrease compared to both the sponge iron system (68.69 mg/L) and the carbon source system (56.50 mg/L). Sponge iron is beneficial for providing an electron donor and ensuring an anaerobic system, fostering an environment that promotes microorganism growth while effectively inhibiting the conversion of nitrite to nitrate. In addition, carbon sources play a vital role in ensuring microorganism growth and reproduction, thereby aiding in TN removal. The optimal parameters based on the effectiveness of TN removal in the iron autotrophic denitrification system were determined to be s-Fe0 dosage of 30 g/L and C/N = 1.5. These results suggest that the iron autotrophic denitrification process, driven by sponge iron, can effectively remove nitrite under anaerobic conditions.


Asunto(s)
Desnitrificación , Nitritos , Anaerobiosis , Reactores Biológicos , Carbono , Hierro , Nitrógeno
3.
Angew Chem Int Ed Engl ; : e202410557, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38932706

RESUMEN

The performance and stability of organic metal halide perovskite (OMHP) optoelectronic devices have been associated with ion migration. Understanding of nanoscale resolved organic cation migration mechanism would facilitate structure engineering and commercialization of OMHP. Here, we report a three-dimensional approach for in situ nanoscale infrared imaging of organic ion migration behavior in OMHPs, enabling to distinguish migrations along grain boundary and in crystal lattice. Our results reveal that organic cation migration along OMHP film surface and grain boundaries (GBs) occurs at lower biases than in crystal lattice. We visualize the transition of organic cation migration channels from GBs to volume upon increasing electric field. The temporal resolved results demonstrate the fast MA+ migration kinetics at GBs, which is comparable to diffusivity of halide ions. Our findings help understand the role of organic cations in the performance of OMHP devices, and the proposed approach holds broad applicability for revealing migration mechanisms of organic ions in OMHPs based optoelectronic devices.

4.
Am J Physiol Heart Circ Physiol ; 321(4): H702-H715, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34448637

RESUMEN

Although pulmonary arterial hypertension (PAH) leads to right ventricle (RV) hypertrophy and structural remodeling, the relative contributions of changes in myocardial geometric and mechanical properties to systolic and diastolic chamber dysfunction and their time courses remain unknown. Using measurements of RV hemodynamic and morphological changes over 10 wk in a male rat model of PAH and a mathematical model of RV mechanics, we discriminated the contributions of RV geometric remodeling and alterations of myocardial material properties to changes in systolic and diastolic chamber function. Significant and rapid RV hypertrophic wall thickening was sufficient to stabilize ejection fraction in response to increased pulmonary arterial pressure by week 4 without significant changes in systolic myofilament activation. After week 4, RV end-diastolic pressure increased significantly with no corresponding changes in end-diastolic volume. Significant RV diastolic chamber stiffening by week 5 was not explained by RV hypertrophy. Instead, model analysis showed that the increases in RV end-diastolic chamber stiffness were entirely attributable to increased resting myocardial material stiffness that was not associated with significant myocardial fibrosis or changes in myocardial collagen content or type. These findings suggest that whereas systolic volume in this model of RV pressure overload is stabilized by early RV hypertrophy, diastolic dilation is prevented by subsequent resting myocardial stiffening.NEW & NOTEWORTHY Using a novel combination of hemodynamic and morphological measurements over 10 wk in a male rat model of PAH and a mathematical model of RV mechanics, we found that compensated systolic function was almost entirely explained by RV hypertrophy, but subsequently altered RV end-diastolic mechanics were primarily explained by passive myocardial stiffening that was not associated with significant collagen extracellular matrix accumulation.


Asunto(s)
Ventrículos Cardíacos/fisiopatología , Hipertrofia Ventricular Derecha/etiología , Hipertensión Arterial Pulmonar/complicaciones , Disfunción Ventricular Derecha/etiología , Función Ventricular Derecha , Remodelación Ventricular , Animales , Fenómenos Biomecánicos , Diástole , Modelos Animales de Enfermedad , Fibrosis , Ventrículos Cardíacos/patología , Hipertrofia Ventricular Derecha/patología , Hipertrofia Ventricular Derecha/fisiopatología , Masculino , Modelos Cardiovasculares , Miocardio/patología , Hipertensión Arterial Pulmonar/fisiopatología , Ratas Sprague-Dawley , Sístole , Factores de Tiempo , Disfunción Ventricular Derecha/patología , Disfunción Ventricular Derecha/fisiopatología
5.
Chem Biodivers ; 18(12): e2100687, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34726832

RESUMEN

Toxoplasmosis post serious threaten to human health, leading to severely eye and brain disease, especially for immunocompromised patients and pregnant women. The multiple side effects and long dosing period of current main treatment regiments calls for high effective and low toxicity anti-toxoplasmosis drugs. Herein, we report our efforts to synthesize a series of 2-(piperazin-1-yl)quinazolin-4(3H)-one derivatives and investigate their activity against Toxoplasma gondii tachyzoites in vitro based on cell phenotype screening. Among the 26 compounds, 8w and 8x with diaryl ether moiety at the side chain of piperazine exhibited good efficacy to inhibit T. gondii, with IC50 values of 4 µM and 3 µM, respectively. Structure-activity relationship (SAR) studies implies that hydrophobic aryl at the side chain would be preferred for improvement of activity. Molecular docking study reveals these two compounds appeared high affinity to TgCDPK1 by interaction with the hydrophobic pocket of ATP-binding cleft.


Asunto(s)
Antiprotozoarios/farmacología , Quinazolinonas/farmacología , Toxoplasma/efectos de los fármacos , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Relación Dosis-Respuesta a Droga , Simulación del Acoplamiento Molecular , Estructura Molecular , Pruebas de Sensibilidad Parasitaria , Quinazolinonas/síntesis química , Quinazolinonas/química
6.
Molecules ; 23(5)2018 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-29693609

RESUMEN

A novel heterotrinuclear complex [Cu2(L)Na(µ-NO3)]∙CH3OH∙CHCl3 derived from a symmetric bis(salamo)-type tetraoxime H4L having a naphthalenediol unit, was prepared and structurally characterized via means of elemental analyses, UV-Vis, FT-IR, fluorescent spectra and single-crystal X-ray diffraction. The heterobimetallic Cu(II)⁻Na(I) complex was acquired via the reaction of H4L with 2 equivalents of Cu(NO3)2·2H2O and 1 equivalent of NaOAc. Clearly, the heterotrinuclear Cu(II)⁻Na(I) complex has a 1:2:1 ligand-to-metal (Cu(II) and Na(I)) ratio. X-ray diffraction results exhibited the different geometric behaviors of the Na(I) and Cu(II) atoms in the heterotrinuclear complex; the both Cu(II) atoms are sited in the N2O2 coordination environments of fully deprotonated (L)4− unit. One Cu(II) atom (Cu1) is five-coordinated and possesses a geometry of slightly distorted square pyramid, while another Cu(II) atom (Cu2) is four-coordination possessing a square planar coordination geometry. Moreover, the Na(I) atom is in the O6 cavity and adopts seven-coordination with a geometry of slightly distorted single triangular prism. In addition, there are abundant supramolecular interactions in the Cu(II)⁻Na(I) complex. The fluorescence spectra showed the Cu(II)⁻Na(I) complex possesses a significant fluorescent quenching and exhibited a hypsochromic-shift compared with the ligand H4L.


Asunto(s)
Complejos de Coordinación/síntesis química , Cobre/química , Sodio/química , Complejos de Coordinación/química , Cristalografía por Rayos X , Modelos Moleculares , Estructura Molecular , Oximas/química , Espectrometría de Fluorescencia
7.
Electrophoresis ; 36(14): 1633-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25820688

RESUMEN

Previous studies have demonstrated that a large sample size is needed to reliably estimate population- and locus-specific microsatellite mutation rates. Therefore, we conducted a long-term collaboration study and performed a comprehensive analysis on the mutation characteristics of 19 autosomal short tandem repeat (STR) loci. The STR loci located on 15 of 22 autosomal chromosomes were analyzed in a total of 21,106 samples (11,468 parent-child meioses) in a Chinese population. This provided 217,892 allele transfers at 19 STR loci. An overall mutation rate of 1.20 × 10(-3) (95% CI, 1.06-1.36 × 10(-3) ) was observed in the populations across 18 of 19 STR loci, except for the TH01 locus with no mutation found. Most STR mutations (97.7%) were single-step mutations, and only a few mutations (2.30%) comprised two and multiple steps. Interestingly, approximately 93% of mutation events occur in the male germline. The mutation ratios increased with the paternal age at child birth (r = 0.99, p<0.05), but not maternal age. Last, with the combination analysis of the data from the southern Chinese population, we drew a picture of 19 STR mutations in China. In conclusion, the data from this study will provide useful information in parentage testing, kinship analysis, and population genetics.


Asunto(s)
Repeticiones de Microsatélite , Tasa de Mutación , Paternidad , Adolescente , Adulto , Anciano , Pueblo Asiatico/genética , Niño , China , Análisis Mutacional de ADN , Femenino , Sitios Genéticos , Genética de Población , Humanos , Masculino , Persona de Mediana Edad , Secuencias Repetidas en Tándem , Adulto Joven
8.
Fa Yi Xue Za Zhi ; 29(3): 196-8, 2013 Jun.
Artículo en Zh | MEDLINE | ID: mdl-24303763

RESUMEN

OBJECTIVE: To study the suspected autosomal STR loci mutation cases. METHODS: A total of 227 suspected autosomal STR loci mutation cases were selected from Center of Forensic Sciences, Beijing Genomics Institute. The allelic mutation cases were screened and the number of mutation of each STR loci was statistically analyzed. The CPI value was calculated in order to study the characteristics and rules of the mutations. RESULTS: In the 227 suspected mutation cases, 3 cases were excluded paternity, and 228 mutations were observed at 18 STR loci in the rest of the cases. The average number of STR mutation loci was 1-2. The maximum of mutation step was 4. After using 20A amplification kit, the CPI values in 3 non-parentage cases were all less than 10(4). After using 20A and 10G amplification kits, the CPI values were all larger than 10(4) in all standard parents-child triplet cases and in 99.45% of diad cases. CONCLUSION: The allelic mutation of STR loci is relatively common in forensic cases. By increasing the number of the required STR loci and supplementing the samples of the triplet, the identification errors could be decreased to a great extent when suspected autosomal STR loci mutation occurs.


Asunto(s)
Sitios Genéticos , Repeticiones de Microsatélite , Mutación , Paternidad , Dermatoglifia del ADN , Femenino , Medicina Legal , Frecuencia de los Genes , Humanos , Masculino , Juego de Reactivos para Diagnóstico , Estudios Retrospectivos
9.
Front Vet Sci ; 10: 1281834, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37771944

RESUMEN

[This corrects the article DOI: 10.3389/fvets.2021.687922.].

10.
Bioresour Technol ; 390: 129821, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37806360

RESUMEN

Sponge iron (SI) is a promising material for nitrogen removal from wastewater. This study reveals the potential functions and mechanisms of SI-mediated multiple metabolic processes in the nitrogen removal of Anammox. The results showed that although the SI application prolonged the start-up time of the reactor, achieved efficient and stable nitrogen removal after a successful start-up. The total nitrogen removal efficiency of the SI-Anammox system (92.62%) was 13.30% higher than that of R0 without SI (79.32%). The increase in nitrogen removal performance was accompanied by an increase in SAA and EPS content. Further microbial analysis showed significant enrichment of functional microorganisms, such as Candidatus_Brocadia, Nitrosomonas, Ellin6067, and Nitrospira. Multi-omics evidence suggests that efficient nitrogen removal is ultimately attributable to the enhancement of the specific key Fe- and N-functional genes in Anammox.


Asunto(s)
Compuestos de Amonio , Aguas Residuales , Anaerobiosis , Oxidación-Reducción , Compuestos de Amonio/metabolismo , Hierro , Reactores Biológicos , Nitrógeno/metabolismo , Desnitrificación , Aguas del Alcantarillado
11.
Bioresour Technol ; 368: 128307, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36370944

RESUMEN

The application of sponge iron (SI) carriers can improve the biochemical treatment performance of sequencing batch reactors (SBR) during wastewater treatment. This study used SBR reactors to explore the effects of SI dosage on the nitrogen removal performance and reactor stability and microbial community structure under low temperature and ultra-low load. In contrast to conventional SBR, the average removal rate of total nitrogen (TN) in the biological sponge iron system (BSIS) was increased by 5.38 % for 45 g/L, 18.93 % for 90 g/L, and 13.52 % for 135 g/L, respectively. The nitrogen removal performance and reactor stability showed the best performance under the SI dosage of 90 g/L. The addition of SI formed the anaerobic-anoxic-aerobic microenvironments, which facilitate the propagation of denitrifying bacteria (Saccharimonadales, Hydrogenophaga) and iron bacteria (Rhodoferax and Acinetobacter) in the BSIS. This study provides a new insight on the application of SI in the wastewater treatment.


Asunto(s)
Microbiota , Nitrógeno , Eliminación de Residuos Líquidos , Reactores Biológicos/microbiología , Desnitrificación , Hierro , Aguas Residuales , Aguas del Alcantarillado
12.
J Phys Chem Lett ; 14(50): 11318-11323, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38064367

RESUMEN

Atomic force microscopy (AFM)-based nanoscale infrared (nano-IR) techniques have found extensive application in the fields of chemistry, physics, and materials science, enabling the visualization of nanoscale features that surpass the optical diffraction limit. More recently, tentative investigations have been conducted into the use of these techniques in the field of catalysis, particularly in studying interfacial processes involving molecular monolayer samples. IR nanoimaging and nanospectroscopy offer unique perspectives on catalytic processes. Considering the specific characteristics of catalytic processes, this Perspective highlights the need for and reviews the current status of AFM-based nano-IR techniques for catalysis investigations, which aims to contribute to a deeper understanding of the nanoscale mechanisms underlying the catalytic processes.

13.
Front Microbiol ; 14: 1011719, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37303807

RESUMEN

Salmonella is one of the most important foodborne zoonotic pathogens, causing global morbidity and mortality in both humans and animals. Due to the extensive use of antimicrobials in food-producing animals, the antimicrobial resistance of Salmonella has attracted increasing attention globally. There have been many reports concerning the antimicrobial resistance of Salmonella from food-producing animals, meats and the environment. However, few studies on Salmonella from food-producing animals have been reported in Chongqing municipality, China. The aim of the present study was to determine the prevalence, serovar diversity, sequence types, and antimicrobial resistance of Salmonella isolated from livestock and poultry in Chongqing. Meanwhile, we also want to know the presence of ß-lactamase genes, plasmid-mediated quinolone resistance (PMQR) genes and quinolone resistance-determining region (QRDR) mutations of Salmonella isolates. A total of 129 Salmonella strains were recovered from 2,500 fecal samples at 41 farms from pigs, goats, beef cattle, rabbits, chickens, and ducks. Fourteen serovars were identified, with S. Agona and S. Derby being the dominant serovars. The 129 isolates had high resistance to doxycycline (87.6%), ampicillin (80.6%), tetracycline (79.8%), trimethoprim (77.5%), florfenicol (76.7%) chloramphenicol (72.9%), and trimethoprim-sulfamethoxazole (71.3%), but were susceptible to cefepime. A total of 114 (88.4%) isolates showed multidrug resistant phenotypes. The prevalence of ß-lactamase genes in Salmonella isolates was 89.9% (116/129), and among these isolates, 107 (82.9%) harbored blaTEM, followed by blaOXA (26, 20.2%), blaCTX-M (8, 6.2%), and blaCMY (3, 2.3%). In addition, qnrB, qnrD, qnrS, oqxA, oqxB, and aac(6')-Ib-cr were detected in 11, 2, 34, 34, 43, and 72 PMQR-producing isolates, respectively. Moreover, QRDR mutations were very common in PMQR-positive Salmonella isolates (97.2%, 70/72) with mutation(s) in parC or combinative mutations in gyrA and parC. More significantly, 32 extended spectrum beta-lactamase (ESBL)-producing isolates were identified, and 62.5% of them were found to harbor one to four PMQR genes. Furthermore, 11 sequence types were identified from the isolates, and most of ESBL-producing isolates were attributed to ST34 (15.6%) and ST40 (62.5%). The coexistence of PMQR genes with ß-lactamase genes and the extensive mutations in QRDR present in Salmonella isolates from food-producing animals suggest a potential threat to public health. Reasonable utilization and strict control strategies for antimicrobials in animal husbandry and animal treatment are necessary to reduce the emergence and dissemination of drug-resistant Salmonella isolates.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(2): 402-6, 2012 Feb.
Artículo en Zh | MEDLINE | ID: mdl-22512178

RESUMEN

A new type of humidity sensor based on optical fiber SPR sensor probe was introduced and manufactured. Firstly the sensitivity of optical fiber SPR sensor probe to environment humidity was studied. On this basis, coating with thin PVA film of different thickness and with capacity of adsorbing water molecule on the surface of optical fiber SPR sensor probe, for the purpose of monitoring relative humidity was proposed. The research shows that the SPR sensor probe coated with double layers of thin PVA film gets better detection result, and humidity measurement sensitivity is 1.59%/%RH, being improved notably compared with SPR optical fiber probe. The SPR sensor coated with single layer of thin PVA film has relative humidity measuring sensitivity of 2.411 nm/%RH related to resonance wavelength in high humidity area. In addition, the new type of optical fiber humidity-sensitive probe with PVA film losing efficiency can be reusable after special treatment.

15.
Eur J Trauma Emerg Surg ; 48(3): 1579-1588, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33483765

RESUMEN

PURPOSE: Trauma and hemorrhagic shock (T/HS) is a major cause of morbidity and mortality. Existing treatment options are largely limited to source control and fluid and blood repletion. Previously, we have shown that enteral protease inhibition improves outcomes in experimental models of T/HS by protecting the gut from malperfusion and ischemia. However, enteral protease inhibition was achieved invasively, by laparotomy and direct injection of tranexamic acid (TXA) into the small intestine. In this study, we tested a minimally invasive method of enteral protease inhibitor infusion in experimental T/HS that can be readily adapted for clinical use. METHODS: Wistar rats were exsanguinated to a mean arterial blood pressure (MABP) of 40 mmHg, with laparotomy to induce trauma. Hypovolemia was maintained for 120 min and was followed by reperfusion of shed blood. Animals were monitored for an additional 120 min. A modified orogastric multi-lumen tube was developed to enable rapid enteral infusion of a protease inhibitor solution while simultaneously mitigating risk of reflux aspiration into the airways. The catheter was used to deliver TXA (T/HS + TXA) or vehicle (T/HS) continuously into the proximal small intestine, starting 20 min into the ischemic period. RESULTS: Rats treated with enteral protease inhibition (T/HS + TXA) displayed improved outcomes compared to control animals (T/HS), including significantly improved MABP (p = 0.022) and lactate (p = 0.044). Mass spectrometry-based analysis of the plasma peptidome after T/HS indicated mitigation of systemic proteolysis in T/HS + TXA. CONCLUSION: Minimally invasive, continuous enteral protease inhibitor delivery improves outcomes in T/HS and is readily translatable to the clinical arena.


Asunto(s)
Choque Hemorrágico , Ácido Tranexámico , Animales , Modelos Animales de Enfermedad , Humanos , Intestino Delgado , Isquemia , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/uso terapéutico , Ratas , Ratas Wistar , Choque Hemorrágico/tratamiento farmacológico , Ácido Tranexámico/uso terapéutico
16.
Mol Biol Rep ; 38(4): 2315-22, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21076875

RESUMEN

In the present study, we investigated the diversity distributions of allelic frequencies of 15 short tandem repeats (STRs) loci in a sample of Chinese Hui ethnic group in the Ningxia Hui Autonomous Region. The allelic frequencies of the 15 STR loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA) were obtained from 2975 unrelated healthy Hui individuals. The STR genotyping data of all the samples were generated by DNA extraction, multiple amplification, GeneScan and genotype analysis. The genetic distances among different populations were calculated by using Nei's method and a phylogenetic tree was constructed based on the allelic frequencies of the same 15 STR loci using the neighbor-joining method. A total of 185 alleles were observed in the Hui population, with the corresponding allelic frequencies ranging from 0.0002 to 0.5322. Chi-Square tests showed that all STR loci were in Hardy-Weinberg equilibrium. The forensic statistical parameters of all the loci showed high values. The population data in this study were compared with the previously published population data from other ethnics or areas. The Hui population showed significant differences from the Minnan Han, Uigur, Ewenki, Yi, Tibetan, Maonan and Malay ethnic minority groups in some loci, and from the South Morocco population and the Moroccan population in all the loci. Our results are valuable for human individual identification and paternity testing in the Chinese Hui population and are expected to enrich the genetic information resources of Chinese populations.


Asunto(s)
Pueblo Asiatico/genética , Etnicidad/genética , Repeticiones de Microsatélite/genética , Filogenia , Polimorfismo Genético/genética , China , Análisis por Conglomerados , Frecuencia de los Genes , Genotipo , Humanos
17.
Front Vet Sci ; 8: 687922, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34307527

RESUMEN

Bovine Pasteurella multocida serogroup A (bovine PmA) is one of the most important pathogens causing fatal pneumonia in cattle. However, it is largely unknown how nutrition shapes bovine PmA infection. Here, we discovered that the infected lung held the highest bacterial density than other tissues during infection. By screening the different metabolites between high (lung)- and low (liver)-bacterial density tissues, the present work revealed that L-ascorbic acid and L-aspartic acid directly influenced bovine P. multocida growth. Interestingly, L-ascorbic acid, which is expressed at higher levels in the infected livers, inhibited bovine PmA growth as well as virulence factor expression and promoted macrophage bactericidal activity in vitro. In addition, ascorbic acid synthesis was repressed upon bovine PmA infection, and supplementation with exogenous L-ascorbic acid significantly reduced the bacterial burden of the infected lungs and mouse mortality. Collectively, our study has profiled the metabolite difference of the murine lung and liver during bovine PmA infection. The screened L-ascorbic acid showed repression of bovine PmA growth and virulence expression in vitro and supplementation could significantly increase the survival rate of mice and reduce the bacterial load in vivo, which implied that L-ascorbic acid could serve as a potential protective agent for bovine PmA infection in clinic.

18.
Ying Yong Sheng Tai Xue Bao ; 32(1): 261-270, 2021 Jan.
Artículo en Zh | MEDLINE | ID: mdl-33477234

RESUMEN

The rapid urbanization has greatly changed the spatial pattern and function of regional habitats, profoundly affected the material flow and energy flow between habitats, and also posed a serious threat to habitats and biodiversity. Here, we used InVEST model, landscape index and multiple linear regression to systematically analyze the spatial and temporal variation and influencing factors for the impacts of urbanization on habitat quality in the Loess Plateau and the densely populated areas from 1990 to 2018. The results showed that the urban expansion of Loess Plateau significantly affected habitat quality. Between 1990 and 2018, the area of construction land increased by 49.6%, resulting in a 5.2% reduction in the total area of habitat patch. After 2010, the urban patch area increased, but the patch density and fragmentation decreased, resulting in a spatial pattern of "high outside and low inside" for urban habitat quality. The rate of urban expansion in densely populated areas was significantly negatively correlated with the habitat quality. The average value of habitat quality in the region dropped by 2.7%, whereas the level of habitat degradation increased by 33.4%. The level of habitat quality was unstable, and patches with high-level habitats were easily converted to lower level. The conversion rates of Lanzhou, Xi'an-Xianyang and Taiyuan were 12.9%, 2.9% and 1.7%, respectively. There were eight influencing factors that could effectively explain the spatial variation of habitat quality (R2=68.7%). Among those factors, population density and distance to roads were the main factors for the fragmentation of habitats, while slope, GDP and precipitation had positive effects on the optimization of habitat spatial patterns.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Biodiversidad , China , Urbanización
19.
J Colloid Interface Sci ; 596: 89-99, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33838328

RESUMEN

Construction of binder-free electrodes with hierarchical core-shell nanostructures is considered to be an effective route to promote the electrochemical performance of supercapacitors. In this work, the porous Ni0.5Mn0.5Co2O4 nanoflowers anchored on nickel foam are utilized as framework for further growing Co3O4 nanowires, resulting in the hierarchical sea urchin-like Ni0.5Mn0.5Co2O4@Co3O4 core-shell microspheres on nickel foam. Owing to the advantages brought by unique porous architecture and synergistic effect of the multi-component composites, the as-prepared electrode exhibits a high specific capacitance (931 F/g at 1 A/g), excellent rate performance (77% capacitance retention at 20 A/g) and outstanding cycle stability (92% retention over 5000 cycles at 5 A/g). Additionally, the assembled Ni0.5Mn0.5Co2O4@Co3O4//AC (activated carbon) asymmetric supercapacitor achieves a high energy density (50 Wh/kg at 750 W/kg) and long durability (88% retention after 5000 cycles).

20.
Hepatol Res ; 39(10): 979-87, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19624768

RESUMEN

AIM: To develop a sandwich enzyme-linked immunosorbent assay (ELISA) measuring hepatoma-specific datura stramonium agglutinin-tightly bounding gamma-glutamyltransferase (DSA-GGT) and evaluate its clinical application for hepatocellular carcinoma (HCC) diagnosis. METHODS: Serum DSA-GGT concentrations were measured with the sandwich ELISA system in 96 patients with HCC, 240 patients with chronic liver diseases and 119 healthy subjects. The diagnostic performance of DSA-GGT for HCC was assessed using receiver operating characteristic (ROC) curves. The diagnostic accuracy of DSA-GGT was compared with serum alpha-fetoprotein (AFP). RESULTS: The area under the ROC curve of DSA-GGT in discriminating patients with HCC from non-HCC was 0.865 (95% confidence interval: 0.818-0.915, P < 0.001). Serum DSA-GGT was positive in 67 out of 96 patients with HCC and 23 out of 240 patients with non-HCC diseases. The sensitivity and specificity of DSA-GGT and AFP for the diagnosis of HCC were 69.8% and 90.5%, and 72.9% and 89.1%, respectively. A higher sensitivity (93.8%) in the identification of HCC was observed by combining DSA-GGT and AFP. CONCLUSION: The sandwich ELISA system showed good reliability and reproducibility, and using the measurement, we found that serum DSA-GGT was a valuable marker of HCC, as a usable complementary to AFP. The sensitivity for identifying HCC could be significantly improved by combining DSA-GGT and AFP, and the combination could be used in large-scale screening for HCC in susceptible individuals.

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