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1.
ACS Appl Mater Interfaces ; 16(22): 29049-29059, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38770760

RESUMEN

High-performance photodetectors with the detection capability of linearly polarized light have broad applications in both military and civilian fields. Quasi-one-dimensional ZrS3 as an emerging anisotropic two-dimensional material has come under the spotlight owing to its intriguing properties. However, the performance of the ZrS3 photodetector is seriously restricted by its low responsivity. Herein, a novel high-performance photodetector based on the van der Waals ZrS3/MoS2 heterostructure is proposed. Attributed to the charge trapping-assisted photogating effect, interlayer carrier transitions, and fast spatial separation of the photogenerated electron-hole pairs, the device displays superior photoresponse characteristics ranging from the ultraviolet to the visible spectrum in terms of high responsivity up to 212 A/W, an extraordinary external quantum efficiency of 8.5 × 104%, and a prompt rise/decay time of 0.19/0.38 ms. In addition, owing to the profound birefringence and dichroism effects in ZrS3 together with strong light-matter interactions in the heterostructure, profound linear-polarization sensitivity is demonstrated with a dichroic ratio of about 2.8. Overall, this photodetector not only is integrated with the excellent properties of ZrS3 and monolayer MoS2 but also further enhances the advantages through interlayer couplings, which demonstrate the strong potential of the ZrS3-based devices for high-performance, ultrafast, and polarization-sensitive photodetection.

2.
Chem Sci ; 15(17): 6397-6401, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38699277

RESUMEN

A concise and collective synthetic route to hypocretenolides was developed for the first time. This route features one-pot addition-alkylation and intramolecular 1,3-dipolar cycloaddition to efficiently assemble the 5/7/6 ring system. Our syntheses enabled multigram preparation of hypocretenolide which facilitated further biological evaluation. Preliminary CCK-8 cytotoxic results of hypocretenolide indicated its IC50 values within 1 µM against 4 colon cancer cell lines. Wound healing and transwell assays suggested the promising inhibitory activities of hypocretenolide toward the migratory capabilities of colon cancer cells in vitro. The animal results confirmed that hypocretenolide can inhibit metastasis of colon cancer cells.

3.
Org Lett ; 25(48): 8570-8574, 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-37994662

RESUMEN

Here, we report concise and divergent total syntheses of fusicoccane members brassicicenes A, R, and T. The key feature of the synthesis is the rapid construction of the 5/8/5 tricyclic core via four steps: aldol reaction, Stork-Danheiser transposition, and ring-closing metathesis from known compounds followed by concise oxidation state adjustment.

4.
Inflammopharmacology ; 30(5): 1717-1728, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35943671

RESUMEN

The efficacy of the sulforaphane derivative JY4 was evaluated in acute and chronic mouse models of ulcerative colitis induced by dextran sodium sulfate. Oral administration of JY4 led to significant improvements in symptoms, with recovery of body weight and colorectal length, together with reduced diarrhoea, bloody stools, ulceration of colonic tissue and infiltration of inflammatory cells. The oral bioavailability of JY4, determined by comparing oral dosing with injection into the tail vein, was 5.67%, which was comply with the idea in the intestinal function. Using a dual-luciferase reporter assay, immunofluorescence studies, western blot analysis and immunohistochemical staining, JY4 was shown to significant interfere with the NF-κB-p65 signaling pathway. By preventing the activation of NF-κB-p65, JY4 inhibited the overexpression of downstream inflammatory factors, thereby exerting an anti-inflammatory effect on the intestinal tract. This study thus provides a promising candidate drug, and a new concept for the treatment of ulcerative colitis.


Asunto(s)
Colitis Ulcerosa , Colitis , Animales , Antiinflamatorios/uso terapéutico , Colitis/tratamiento farmacológico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/metabolismo , Colon , Sulfato de Dextran/farmacología , Modelos Animales de Enfermedad , Isotiocianatos , Ratones , FN-kappa B/metabolismo , Sulfóxidos
5.
Comput Intell Neurosci ; 2022: 2290644, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35222623

RESUMEN

This study presents an optimization approach for scheduling the operation room for emergency surgeries, considering the priority of surgeries. This optimization model aims to minimize the costs associated with elective and emergency surgeries and maximize the number of scheduled surgeries. In this study, surgeon assistants to perform each surgery are considered in order to achieve the goals. Since the time of each surgery varies according to the conditions of the patient, this parameter is considered as an uncertain one, and a robust optimization method is applied to deal with uncertainty. To demonstrate the effectiveness of the proposed method, a case study in one of the East Asian hospitals is presented and analyzed using GAMS software. Moreover, hybrid simulation and gray wolf optimization algorithm (GWO) have been implemented to solve the optimization model in different scenarios. The results show that increasing the risk parameters in the robust optimization model will increase the system costs. Moreover, in case of uncertainty, the solutions obtained from the GWO simulation method are on average 73.75% better than the solutions obtained from the GWO algorithm.


Asunto(s)
Inteligencia Artificial , Quirófanos , Algoritmos , Simulación por Computador , Humanos , Incertidumbre
6.
Chemosphere ; 227: 496-504, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31004816

RESUMEN

Wetland plants are proven to perform well in water treatment. However, the phytoremediation capability of wetland plants for antibiotics, especially the uptake and metabolism involved in vivo, is poorly understood. In this study, we investigated the removal, uptake, and specific metabolism by Canna indica and Iris pseudacorus of five sulfonamides (SAs) using hydroponic experiments for seven days. The removal of SAs ranged from 15.2% to 98.4% in the planted groups, whereas that in the unplanted control group was much lower (12.6%-39.9%). The accumulation of SAs in plants was in a concentration-dependent manner via an active process and is not a major removal mechanism (constituted 0.31%-3.62% of the total removal load in plant system). The results also showed differences in the removal and accumulation by plant species of SAs. The acetyl conjugates (N-acetyl SA) were formed, which significantly enhanced the uptake of SAs (P < 0.001) except sulfapyridine. The concentrations of N-acetyl SA accounted for only 0.4%-23.8% of the total SAs distribution in plants, suggesting the involvement of other metabolism pathways. Methylation and oxidation metabolites were identified in plant tissues and no SA-induced growth stress occurred, revealing that antibiotic metabolism in vivo should be associated with the ability of wetland plants to accumulate antibiotic and tolerate antibiotic stress.


Asunto(s)
Biodegradación Ambiental , Plantas/metabolismo , Sulfonamidas/metabolismo , Humedales , Antibacterianos/metabolismo , Antibacterianos/farmacocinética , Transporte Biológico , Tolerancia a Medicamentos , Iris/metabolismo , Estrés Fisiológico , Sulfonamidas/farmacocinética , Purificación del Agua
7.
Chemosphere ; 210: 29-37, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29980069

RESUMEN

The prevalence of cyanobacterial bloom (Cyano-bloom) and hepatotoxic microcystin (MC) pollution caused by eutrophication poses serious problems to aquatic ecosystems and public health. However, conventional water treatment technologies are inefficient for removing cyanotoxins. In this study, the performance of microcosm constructed wetlands (CWs) in the removal of Cyano-bloom, microcystin-LR (MC-LR), and nutrients was investigated following repeated loading of pollutants. The effects of plant and bioaugmentation of selected MC-LR degrading bacteria on removal efficiency, degrading gene mlrA abundance, and bacterial community structure were examined. More than 90% of the MC-LR and chlorophyll-a was eliminated by CWs after 3 d of hydraulic retention time (HRT) without a lag phase. No significant differences between planted and unplanted CWs were found in the MC-LR and Cyano-bloom removal and mlrA gene abundance. Nevertheless, the plants improved nutrient removal to reduce eutrophication. Bioaugmentation markedly enhanced the degradation of MC-LR from 16.7 µg L-1 to below the threshold value within 12 h, which could help shorten the HRT of CWs by increasing functional MC-LR degrading bacteria. In the soil of CWs, the following six bacterial genera with MC-LR-degrading potential were found: Sphingopyxis, Methylotenera, Pseudomonas, Methylosinus, Novosphingobium, and Sphingomonas. Among them, the first three also significantly proliferated in CWs with bioaugmentation during MC-LR degradation, indicating their high adaptability and MC-LR removal contribution. These results suggested that CWs could provide suitable conditions for MC-LR degrading microorganism proliferation, and CWs with bioaugmentation could be effective and practical measures for the remediation of eutrophication and MC pollution.


Asunto(s)
Cianobacterias/metabolismo , Microcistinas/aislamiento & purificación , Humedales , Biodegradación Ambiental , Eutrofización , Toxinas Marinas , Microcystis/aislamiento & purificación , Purificación del Agua/métodos
8.
Environ Technol ; 39(16): 2138-2150, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28678620

RESUMEN

Untreated water from mining sites spreads heavy metal contamination. The present study assessed the phytoextraction performance of heavy metal-accumulating plants and the effects of chemical chelators on cadmium (Cd), lead (Pb), zinc (Zn), and copper (Cu) removal from paddy fields that have been continuously irrigated with mining wastewater from mines for 55 years. Outdoor pot experiments showed that the total Pb, Zn, and Cd content was lower in the rhizosphere soil of Amaranthus hypochondriacus than in that of Sedum alfredii, Solanum nigrum, and Sorghum bicolor. The aboveground biomass (dry weight) and relative growth rate of A. hypochondriacus were significantly higher than that of the other three species (P < .05). However, the total metal accumulation was significantly higher in the A. hypochondriacus system than in the other plants' system (P < .05). The increase in shoot biomass of A. hypochondriacus depended mostly on the chelator type [ethylenediaminetetraacetic acid (EDTA), malate, oxalate, and citrate] and their application frequency. Single application of EDTA significantly increased the shoot biomass of A. hypochondriacus and total metal removal loading from soil (P < .05). In conclusion, A. hypochondriacus may be effective for in situ phytoremediation of heavy metal-contaminated farmland soil and EDTA can accelerate the phytoextraction effect.


Asunto(s)
Riego Agrícola , Contaminantes del Suelo , Aguas Residuales , Biodegradación Ambiental , Quelantes , Plomo , Metales Pesados , Suelo , Zinc
9.
ACS Appl Mater Interfaces ; 9(16): 14180-14186, 2017 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-28387517

RESUMEN

N-doped carbon materials is of particular attraction for anodes of lithium-ion batteries (LIBs) because of their high surface areas, superior electrical conductivity, and excellent mechanical strength, which can store energy by adsorption/desorption of Li+ at the interfaces between the electrolyte and electrode. By directly carbonization of zeolitic imidazolate framework-8 nanospheres synthesized by an emulsion-based interfacial reaction, we obtained N-doped hollow carbon nanospheres with tunable shell thickness (20 nm to solid sphere) and different N dopant concentrations (3.9 to 21.7 at %). The optimized anode material possessed a shell thickness of 20 nm and contained 16.6 at % N dopants that were predominately pyridinic and pyrrolic. The anode delivered a specific capacity of 2053 mA h g-1 at 100 mA g-1 and 879 mA h g-1 at 5 A g-1 for 1000 cycles, implying a superior cycling stability. The improved electrochemical performance can be ascribed to (1) the Li+ adsorption dominated energy storage mechanism prevents the volume change of the electrode materials, (2) the hollow nanostructure assembled by the nanometer-sized primary particles prevents the agglomeration of the nanoparticles and favors for Li+ diffusion, (3) the optimized N dopant concentration and configuration facilitate the adsorption of Li+; and (4) the graphitic carbon nanostructure ensures a good electrical conductivity.

10.
Res Dev Disabil ; 60: 83-95, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27914305

RESUMEN

This study assessed the effects of a cross-circuit training intervention program on the body composition, cardiorespiratory fitness, balance, and muscular strength endurance of overweight or obese students with intellectual disability. A total of 43 students with intellectual disability (aged 13-19 years) were enrolled in this program; 28 overweight/obese students were assigned to either an obesity-control group (n=14) or obesity-exercise group (n=14), and those with normal weight were assigned to a normal weight group (n=15). The experiment was divided into three periods: pretest (involving the three groups), exercise intervention (involving only the obesity-exercise group), and post-test (involving the obesity-exercise and obesity-control groups). The test involved measuring the body composition, 1-min sit-ups, dynamic and static balance, vertical jumps, and modified Bruce treadmill protocols for measuring cardiorespiratory fitness. The exercise program involving the cross-circuit training concept was conducted nonstop with different types of exercise activities. The training program lasted 12 weeks, and it was executed 5days a week, with each daily session lasting 50min. The results revealed that the obesity-exercise group demonstrated reduced weight, BMI, and fat mass after the intervention program. Moreover, the exercise tolerance test (including total exercise time and maximal heart rate), dynamic balance, sit-up, and vertical jump performance of the participants improved significantly. In conclusion, the cross-circuit training program effectively improved cardiorespiratory fitness, dynamic balance, muscular strength and endurance, and weight control in overweight or obese students with intellectual disability enrolled in a special education school.


Asunto(s)
Capacidad Cardiovascular , Educación Especial , Terapia por Ejercicio/métodos , Discapacidad Intelectual/rehabilitación , Fuerza Muscular , Obesidad/rehabilitación , Resistencia Física , Equilibrio Postural , Adolescente , Composición Corporal , Índice de Masa Corporal , Estudios de Casos y Controles , Prueba de Esfuerzo , Tolerancia al Ejercicio , Femenino , Humanos , Discapacidad Intelectual/complicaciones , Masculino , Obesidad/complicaciones , Sobrepeso/complicaciones , Sobrepeso/rehabilitación , Aptitud Física , Instituciones Académicas , Pérdida de Peso , Adulto Joven
11.
PLoS One ; 9(12): e114777, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25486118

RESUMEN

Recently, a large meta-analysis of five genome wide association studies (GWAS) identified a novel locus (rs2718058) adjacent to NME8 that played a preventive role in Alzheimer's disease (AD). However, this link between the single nucleotide polymorphism (SNP) rs2718058 and the pathology of AD have not been mentioned yet. Therefore, this study assessed the strength of association between the NME8 rs2718058 genotypes and AD-related measures including the cerebrospinal fluid (CSF) amyloid beta, tau, P-tau concentrations, neuroimaging biomarkers and cognitive performance, in a large cohort from Alzheimer's Disease Neuroimaging Initiative (ADNI) database. We used information of a total of 719 individuals, including 211 normal cognition (NC), 346 mild cognitive impairment (MCI) and 162 AD. Although we didn't observe a positive relationship between rs2718058 and AD, it was significantly associated with several AD related endophenotypes. Among the normal cognitively normal participants, the minor allele G carriers showed significantly associated with higher CDRSB score than A allele carriers (P = 0.021). Occipital gyrus atrophy were significantly associated with NME8 genotype status (P = 0.002), with A allele carriers has more atrophy than the minor allele G carriers in AD patients; lateral ventricle (both right and left) cerebral metabolic rate for glucose (CMRgl) were significantly associated with NME8 genotype (P < 0.05), with GA genotype had higher metabolism than GG and AA genotypes in MCI group; the atrophic right hippocampus in 18 months is significantly different between the three group, with GG and AA genotypes had more hippocampus atrophy than GA genotypes in the whole group. Together, our results are consistent with the direction of previous research, suggesting that NME8 rs2718058 appears to play a role in lowering the brain neurodegeneration.


Asunto(s)
Enfermedad de Alzheimer/genética , Biomarcadores/análisis , Trastornos del Conocimiento/etiología , Neuroimagen , Polimorfismo Genético/genética , Tiorredoxinas/genética , Anciano , Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/patología , Trastornos del Conocimiento/líquido cefalorraquídeo , Trastornos del Conocimiento/patología , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Masculino , Pruebas Neuropsicológicas
12.
ACS Appl Mater Interfaces ; 6(20): 18163-71, 2014 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-25247890

RESUMEN

Metal-organic frameworks (MOFs) represent an emerging class of crystalline materials with well-defined pore structures and hold great potentials in a wide range of important applications. The functionality of MOFs can be further extended by integration with other functional materials, e.g., encapsulating metal nanoparticles, to form hybrid materials with novel properties. In spite of various synthetic approaches that have been developed recently, a facile method to prepare hierarchical hollow MOF nanostructures still remains a challenge. Here we describe a facile emulsion-based interfacial reaction method for the large-scale synthesis of hollow zeolitic imidazolate framework 8 (ZIF-8) nanospheres with controllable shell thickness. We further demonstrate that functional metal nanoparticles such as Pd nanocubes can be encapsulated during the emulsification process and used for heterogeneous catalysis. The inherently porous structure of ZIF-8 shells enables encapsulated catalysts to show size-selective hydrogenation reactions.

13.
Environ Geochem Health ; 34(3): 323-35, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21881861

RESUMEN

Concentrations and distributions of selected fluoroquinolones (norfloxacin, ciprofloxacin and enrofloxacin) in water, sediments and nine kinds of fish species collected from 6 sites in two marine aquaculture regions of the Pearl River Delta, China, were analyzed by using high-performance liquid chromatography with fluorescence detector (HPLC). The results showed that the concentrations of ciprofloxacin and enrofloxacin were below the limits of quantification (LOQ) in all water samples except for norfloxacin. Norfloxacin and ciprofloxacin concentrations ranged from 1.88 to 11.20 ng g(-1) dry wt, 0.76-2.42 ng g(-1) dry wt in sediments collected from the Dapeng'ao region (sites 1-3) and ranged from 2.31 to 4.75 ng g(-1) dry wt, 1.26-1.76 ng g(-1) dry wt in sediments collected from the Hailing Island region (sites 4-6), respectively. However, no enrofloxacin was found in all sediment samples. The three fluoroquinolones (FQs) were detected in all fish samples, and the concentrations were higher in liver tissues than those in muscle tissues. The levels of norfloxacin were higher than ciprofloxacin and enrofloxacin in both liver and muscle tissues. Among the nine marine fish species, Siganus fuscescens from Hailing Island had a significantly high level of norfloxacin in liver tissue (254.58 ng g(-1) wet wt), followed by Sparus macrocephalus (133.15 ng g(-1) wet wt) from Dapeng'ao, and the lowest value was Lutianus argentimaculatus (5.18 ng g(-1) wet wt) from Hailing Island. The obtained results of FQs in present study do not represent a risk to the human health in Guangdong coastal area, based on the maximum residue limits (MRLs) established by Chinese Government and the acceptable daily intake (ADI) recommended by the Food and Agriculture Organization and World Health Organization (FAO/WHO).


Asunto(s)
Antiinfecciosos/análisis , Ciprofloxacina/análisis , Norfloxacino/análisis , Perciformes/metabolismo , Contaminantes Químicos del Agua/análisis , Animales , Antiinfecciosos/metabolismo , China , Cromatografía Líquida de Alta Presión , Ciprofloxacina/metabolismo , Monitoreo del Ambiente/normas , Sedimentos Geológicos/análisis , Humanos , Límite de Detección , Norfloxacino/metabolismo , Medición de Riesgo , Agua de Mar/análisis , Especificidad de la Especie , Contaminantes Químicos del Agua/metabolismo
14.
Biochim Biophys Acta ; 1800(6): 565-73, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20188798

RESUMEN

BACKGROUND: The Rh blood D group provides a clinically important model of aberrant splicing with skipped exons. Approximately 30% of serologically D-negative Chinese individuals have an intact RHD gene (DEL phenotype) and induce allo-immunization in transfusions. The RHD1227GNA polymorphism occurs in >95% DEL phenotype of Asian descent. The effects of RHD 1227A and a novel allele on exon 9 splicing were examined. RESULTS: Amplified DEL RNA products revealed that 3 transcripts involved skipping of exons 8-9, exon 9, or exon 9 with an inserted 170-bp cryptic exon located between exons 7 and 8. A novel, single nucleotide polymorphism was identified in the 7th intron, (IVS7) 923C>T, and present in all DEL patients. The odds ratio of RHD1227G>A allele with DEL phenotype was 2711. Splicing analysis of transcripts from minigenes containing the 1227GNA allele, but not the (IVS7) 923C>T allele, demonstrated aberrant exon 9 skipping. CONCLUSIONS: A combined haplotype of 1227G>A and IVS7 923C>T alleles was apparent in >95% DEL Chinese individuals. RHD1227A mutation significantly increased aberrant mRNA splicing, producing a hybrid RHD mRNA lacking exon 9. These results provide a molecular basis of the DEL phenotype in the Chinese population.


Asunto(s)
Exones , Empalme del ARN , Sistema del Grupo Sanguíneo Rh-Hr/genética , Alelos , Secuencia de Bases , Cartilla de ADN , Humanos , Reacción en Cadena de la Polimerasa , Taiwán
15.
Sheng Wu Gong Cheng Xue Bao ; 25(6): 892-6, 2009 Jun.
Artículo en Chino | MEDLINE | ID: mdl-19777818

RESUMEN

To improve mass transfer and enhance the yield for C(1,2) biodehydrogenation of steroid 11beta-hydroxyl medroxyprogesterone, we carried out the dehydrogenation reaction of 11beta-hydroxyl medroxyprogesterone in an oil-in-water (O/W) microemulsion by Arthrobacter simplex UR016. We studied the effects of system composition, dehydrogenation temperature and substrate concentration on microbial transformation. We formulated a suitable O/W microemulsion system with Arthrobacter simplex UR016 culture broth as aqueous phase, 10 g/L of edible oil as oil phase, 4 g/L of Tween-O80 and 7% (V/V) alcohol as surfactant and cosurfactant. The optimal dehydrogenation temperature was 33 degrees C. The results showed that in Tween-80/alcohol/edible oil/water microemulsion system, the hydrophobic steroid was solubilised and diffused effectively, with the maximum conversion rate of 88.6% at 46 h under 4 g/L substrate concentration, an increase of 66.2% compared to that in aqueous system. The C(1,2) biodehydrogenation of 11beta-hydroxyl medroxyprogesterone is more efficient in water-edible oil microemulsion system than in aqueous system.


Asunto(s)
Arthrobacter/metabolismo , Medroxiprogesterona/química , Medroxiprogesterona/metabolismo , Biotransformación , Emulsiones , Hidrogenación
16.
Ecotoxicology ; 18(6): 677-84, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19495962

RESUMEN

The toxic effects of norfloxacin (NOR) and butylated hydroxyanisole (BHA) on the microalga Scenedesmus obliquus were assessed in terms of growth rate, concentration of chlorophyll a, activities of 7-ethoxyresorufin-o-dealkylases (EROD), glutathione s-transferase (GST), catalase (CAT) and total malondialdehyde content (MDA). The 96 h EC(50) was 38.49 and 11.12 mg/l for NOR and BHA, respectively. Growth of S. obliquus was affected slightly under low concentrations of BHA (<4 mg/l) and NOR (<15 mg/l) over the 96 h exposure period. With the increasing concentrations of these two compounds, growth of S. oblique decreased significantly. Growth inhibition was 82.4% at 60.0 mg/l for NOR and 60.6% at 16.0 mg/l for BHA after 96 h. A similar trend was also observed for chlorophyll alpha. NOR and BHA affected Phase I and Phase II enzyme activities differently. Upon exposure to NOR, EROD was induced at concentration <15.0 mg/l and depressed at concentrations >30 mg/l significantly. CAT and GST exhibited similar trends during the exposure period. Compared to controls, MDA content only showed high induction at high concentrations of NOR (>30 mg/l). However, EROD activity did not display any change compared to control responses during BHA exposure, whereas GST showed significant induction for all concentrations over the exposure period. CAT activity showed induction at low concentration and depression at high concentration. MDA content increased with the rise of BHA during the exposure period. These types of assays, revealing toxic effects of NOR and BHA to phototrophs, could be employed to assess the potential risks of these xenobiotics to aquatic ecological systems.


Asunto(s)
Hidroxianisol Butilado/toxicidad , Agua Dulce/análisis , Norfloxacino/toxicidad , Scenedesmus/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Catalasa/metabolismo , Clorofila/metabolismo , Clorofila A , Citocromo P-450 CYP1A1/metabolismo , Relación Dosis-Respuesta a Droga , Glutatión Transferasa/metabolismo , Norfloxacino/análisis , Estrés Oxidativo/efectos de los fármacos , Scenedesmus/enzimología , Scenedesmus/crecimiento & desarrollo , Factores de Tiempo , Pruebas de Toxicidad
17.
Transl Res ; 149(1): 31-6, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17196520

RESUMEN

The Rhesus (Rh) blood group is the most polymorphic blood group system. Serological analyses revealed that only 0.1% to 0.4% of the Chinese population exhibited a D-negative phenotype. In contrast to D-negative Caucasian persons, who are mostly associated with a deletion of RHD between the upstream and downstream Rhesus boxes, approximately 30% of apparently D-negative Chinese were actually DEL, potentially harboring a grossly intact RHD gene. The authors' previous detection of the RHD 1227A allele in all DEL samples prompted the conclusion that the RHD 1227A gene is highly prevalent in DEL populations of Chinese ethnicity, which indicates that it may be a marker for the rapid detection of DEL. Currently, random surveys for RHD 1227 A allele and for hybrid Rhesus box were conducted among 399 Han Chinese in Taiwan. The estimated frequencies of RHD 1227G/G, RHD 1227A/G, RHD A/A, RHD 1227G/-, RHD 1227A/-, and RHD-/- were 0.89054, 0.0118, 0.00016, 0.0414, 0.00055, and 0.00192, respectively. These results were consistent with the prevalence of D-negative and DEL in persons of Chinese ethnicity. The authors conclude that detection of RHD 1227A and hybrid Rhesus box alleles is predictive of Rh phenotypes in the Chinese population.


Asunto(s)
Sistema del Grupo Sanguíneo Rh-Hr/genética , Adolescente , Adulto , Femenino , Eliminación de Gen , Frecuencia de los Genes , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Taiwán/etnología
18.
J Hazard Mater ; 133(1-3): 276-82, 2006 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-16314041

RESUMEN

With the growing general concern about the pollution by fly ash (FA), there has been global interest in its utilization. Purified FA or FA micro-beads are suitable as polymer filling materials because of their density, good dispersity and fluidity of globular particles. However, FA as a filler has not been widely used up to now on account of low whiteness values and low friction of untreated FA surface. In order to improve the FA quality, a surface modification method by using isothermal heating is proposed in this paper. Preparation of composite fly ash (CFA) in the Ca(OH)(2)-H(2)O-CO(2) system is described. Good coating results on FA surfaces can be achieved under suitable operating parameters. The characteristics of CFA are discussed and analyzed based on data from X-ray diffraction, scanning electron microscopy (SEM), infrared spectra, and BET multiple-point nitrogen adsorption method. Feedstocks with less than 45 microm grain size, 2.86 m(2) g(-1) specific surface area, and 36.68 whiteness value revealed an increase in specific surface area ranging from 8.69 to 10.01 m(2) g(-1) and an increase in whiteness values ranging from 63.67 to 73.13 after coating. A SEM study allowed a detailed determination of the morphology of the surface roughness. Filling tests also show that a rough surface of the CFA enhances contact opportunities and improves the interface between polymer and CFA blended with polypropylene (PP).


Asunto(s)
Carbono/química , Carbono/aislamiento & purificación , Polímeros/química , Ceniza del Carbón , Calor , Microscopía Electrónica de Rastreo , Material Particulado , Silicatos/química , Espectroscopía Infrarroja por Transformada de Fourier , Factores de Tiempo , Difracción de Rayos X
19.
J Lab Clin Med ; 146(6): 321-5, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16310514

RESUMEN

The Rhesus (Rh) blood group is the most polymorphic human blood group system, and it is clinically significant in transfusion medicine. About 15% of Caucasoid people are RhD-negative, whereas in the Asian population, the RhD-negative blood type only occurs in 0.1% to 0.5%. However, approximately 30% of apparently RhD-negative Taiwanese people actually were RhD(el). Traditionally, we verify RhD(el) by a serologically adsorption-elution procedure with polyclonal anti-D. In our recent report, RhC phenotype is highly associated with RhD(el), and RHD1227A is a useful genetic marker for RhD(el). For setting up a rapid protocol to detect RhD(el) in clinical laboratory, a total number of 395 Taiwanese serological RhD-negative blood samples, those with RhC (+) phenotypes as selected by serological tests, were further screened by adsorption/elution tests and RHD1227A allele by specific sequence primer-polymerase chain reaction (SSP-PCR) for RhD(el). Among 395 blood samples collected from RhD-negative subjects, the incidence of RhC (+) was 43% (171/395). One hundred and twenty six of the 171 RhC (+) samples were positive for both adsorption/elution for RhD detection and SSP-PCR assay for RHD1227A. The sensitivity and specificity were 96.9% and 97.5%, respectively, for RHD1227A detection as compared with the traditional adsorption/elution test. Our results also indicated that RHD1227A was highly linked to Ce haplotypes (95.2%). In conclusion, combined RhC (+) phenotyping and RHD1227A analysis can be a simple and accurate laboratory screening protocol for RhD(el) detection in RhD-negative population.


Asunto(s)
Medicina Clínica/métodos , Sistema del Grupo Sanguíneo Rh-Hr/genética , Pueblo Asiatico/genética , Genotipo , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Taiwán
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