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1.
Magn Reson Med Sci ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38749758

RESUMEN

PURPOSE: To investigate the predictive performance of radiomic features extracted from breast MRI for upgrade of ductal carcinoma in situ (DCIS) to invasive carcinoma. METHODS: This retrospective study included 71 women with DCIS lesions diagnosed preoperatively by biopsy. All women underwent breast dynamic contrast-enhanced (DCE) MRI of the breast, which included pre-contrast and five post-contrast phases continuously with a time resolution of 60s. Lesion segmentation was performed manually, and 144 radiomic features of the lesions were extracted from T2-weighted images (T2WI), pre-contrast T1-weighted images (T1WI), and post-contrast 1st, 2nd, and 5th phase subtraction images on DCE-MRI. Qualitative features of mammography, ultrasound, and MRI were also assessed. Clinicopathological features were evaluated using medical records. The least absolute shrinkage and selection operator (LASSO) algorithm was applied for features selection and model building. The predictive performance of postoperative upgrade to invasive carcinoma was assessed using the area under the receiver operating characteristic curve. RESULTS: Surgical specimens revealed 13 lesions (18.3%) that were upgraded to invasive carcinoma. Among clinicopathological and qualitative features, age was the only significant predictive variable. No significant radiomic features were observed on T2WI and post-contrast 2nd phase subtraction images on DCE-MRI. The area under the curves (AUCs) of the LASSO radiomics model integrated with age were 0.915 for pre-contrast T1WI, 0.862 for post-contrast 1st phase subtraction images, and 0.833 for post-contrast 5th phase subtraction images. The AUCs of the 200-times bootstrap internal validations were 0.885, 0.832, and 0.775. CONCLUSION: A radiomics approach using breast MRI may be a promising method for predicting the postoperative upgrade of DCIS. The present study showed that the radiomic features extracted from pre-contrast T1WI and post-contrast subtraction images in the very early phase of DCE-MRI were more predictable.

2.
Breed Sci ; 73(5): 445-449, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38737920

RESUMEN

Tan spot, a foliar disease of Triticum spp. such as bread wheat (T. aestivum L.) and durum wheat (T. turgidum ssp. durum (Desf.) Husn.) caused by the filamentous fungus Pyrenophora tritici-repentis (Died.) Drechsler leads to serious losses of crop yield and quality in some areas in Japan. P. tritici-repentis is classified into eight races according to the combinations of three necrotrophic effectors, PtrToxA, PtrToxB, and PtrToxC encoded by ToxA, ToxB, and ToxC1, respectively. Race classification has been based on reaction of a differential variety to necrotrophic effectors, which is tested by inoculation. Recent identification of the Tox genes and development of specific DNA markers have enabled us to classify races of P. tritici-repentis collected in Japan by Tox gene genotyping. We found that 17 strains collected from Triticum spp. in Japan were mainly race 1 or 2, because they carried ToxA as a toxin gene by current race classification; wheat genotype tsn1 is resistant to ToxA. Establishment of wheat cultivars carrying tsn1 would be most effective for decreasing agronomic losses caused by the disease in Japan.

3.
PLoS One ; 17(9): e0274584, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36107972

RESUMEN

Ice slurry ingestion enhances exercise performance by lowering the core body temperature. However, an operational issue related to this ingestion is the requirement for a high intake of 7.5 g·kg-1 to produce the desired effects. We investigated the effects of the intake of low amounts of ice slurry at -2°C on the tympanic temperature and exercise performance during repeated high-intensity intermittent exercises in a hot environment. This study was a randomized, crossover study, with a 6-day washout period. Twelve university rugby union players performed two 30-min sessions of high-intensity intermittent exercises separated by a 15-min half-time break on a cycle ergometer in a hot environment (28.8°C ± 0.1°C, 49.5% ± 0.6% relative humidity). The participants ingested 450 g of -2°C-ice slurry (ICE), or a 30°C-beverage (CON) having the same composition as ICE, or 30°C-water (WAT) during the half-time break. The tympanic temperature and skin temperature were measured as the physiological data, and the peak power and mean power as the exercise performance data. The tympanic temperature at the half-time break and beginning of the 2nd session was significantly lower in the ICE group as compared with the CON and WAT groups. The skin temperature at the half-time break was significantly lower in the ICE group as compared with the WAT group. While the peak power and mean power during the 2nd session were significantly greater in the ICE group as compared with the CON and WAT groups. Our findings suggest that even the intake of lower amounts, as compared with those used in previous studies, of low-temperature ice slurry can reduce the body temperature and improve the peak power. These results suggest that intake of low-temperature ice slurry as a strategy for internal body cooling is useful for improving endurance exercise performance in hot environments.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Regulación de la Temperatura Corporal/fisiología , Estudios Cruzados , Ingestión de Alimentos , Calor , Humanos , Rendimiento Físico Funcional , Agua
4.
Breed Sci ; 72(5): 355-361, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36776440

RESUMEN

Improvement of preharvest sprouting (PHS) resistance is an important objective in the breeding of durum wheat (Triticum turgidum ssp. durum (Desf.) Husn.) in Japan, where the harvest timing overlaps with the rainy season. In a previous study, we showed that an R-gene associated with red seed color was the most effective at promoting PHS resistance in durum wheat. However, red-seeded durum wheat is not popular because it discolors pasta. Here, to improve PHS resistance without the R-gene, we introduced a PHS resistance allele of MOTHER OF FT AND TFL 1 (MFT) and a mutated ABA 8'-hydroxylase (ABA8'OH1-A), which is involved in abscisic acid (ABA) catabolism, singly or together into white-seeded durum wheat. The introduction of both genes reliably and stably improved PHS resistance under all tested conditions. Modification of ABA catabolism might be an effective way to improve PHS resistance in durum wheat. Our findings will contribute to improved PHS resistance in breeding for white-seeded durum wheat.

5.
Breed Sci ; 70(3): 331-341, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32714055

RESUMEN

Cadmium (Cd) is as an extremely toxic metal that can contaminate agricultural soils. To reduce the risk of Cd intake in food cereals, the development of cultivars with low grain Cd concentration (GCC) is an effective countermeasure. We analyzed quantitative trait loci (QTLs) for GCC in a doubled haploid (DH) common wheat (Triticum aestivum L.) population derived from 'Chugoku 165' (low GCC) × 'Chukei 10-22' (high GCC). We found novel loci for low GCC on the short arm of chromosome 4B and on the long arm of chromosome 6B. These QTLs accounted for 9.4%-25.4% (4B) and 9.0%-17.8% (6B) of the phenotypic variance in the DH population. An association analysis with 43 cultivars identified 3 loci at these QTLs: QCdc.4B-kita, QCdc.6B-kita1, and QCdc.6B-kita2. In contrast to durum wheat and barley, no QTL was detected on the chromosomes of homeologous group 5 for heavy metal P1B-type ATPase 3. These results will contribute to marker-assisted selection for low GCC in breeding of common wheat.

6.
Micromachines (Basel) ; 11(4)2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32331468

RESUMEN

High throughput reconstruction of in vivo cellular environments allows for efficient investigation of cellular functions. If one-side-open multi-channel microdevices are integrated with micropumps, the devices will achieve higher throughput in the manipulation of single cells while maintaining flexibility and open accessibility. This paper reports on the integration of a polydimethylsiloxane (PDMS) micronozzle array and bidirectional electrokinetic pumps driven by DC-biased AC voltages. Pt/Ti and indium tin oxide (ITO) electrodes were used to study the effect of DC bias and peak-to-peak voltage and electrodes in a low conductivity isotonic solution. The flow was bidirectionally controlled by changing the DC bias. A pump integrated with a micronozzle array was used to transport single HeLa cells into nozzle holes. The application of DC-biased AC voltage (100 kHz, 10 Vpp, and VDC: -4 V) provided a sufficient electroosmotic flow outside the nozzle array. This integration method of nozzle and pumps is anticipated to be a standard integration method. The operating conditions of DC-biased AC electrokinetic pumps in a biological buffer was clarified and found useful for cell manipulation.

7.
J Nanosci Nanotechnol ; 19(5): 2913-2924, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30501800

RESUMEN

We fabricated p-type boron (B)-doped silicon nanoparticles (SiNPs) with a mean diameter of 3.4 nm by a complex chemical reaction of inexpensive pure Si and pure B powders using a combination of ultra-high-speed mixing and thermal annealing techniques. The hole concentration in the p-type SiNPs increased with increasing Si:B blend ratio because of the incorporation of electrically active B atoms into the SiNP core; thus, the conductance of the p-type SiNPs was also enhanced by increasing the mobile carrier concentration. Furthermore, we discuss the effect of the Si:B blend ratio on the photovoltaic performances of the heterojunction solar cells consisting of poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) (PEDOT:PSS)/p-type SiNPs/n-type Si with a micro-pyramidal structure. The photovoltaic parameters decreased with increasing Si:B blend ratio because of the influence of the insufficient collection rate of the separated charge carriers resulting from reduction in the pn junction region and increase in the carrier recombination. This resulted in the highest power conversion efficiency of 2.57% at a low Si:B blend ratio. These findings are important for designing heterojunction solar cells using p-type SiNPs.

8.
Insect Biochem Mol Biol ; 84: 40-47, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28414175

RESUMEN

A trypsin-like protease called initiatorin is known to initiate sperm motility in the silkworm, Bombyx mori, but little is known about the signaling events leading to sperm flagellar beating. The aim of this study was to investigate whether this mechanism of sperm motility activation involves the signaling transmitter nitric oxide (NO). NO is produced from the amino acid L-arginine by the enzyme action of nitric oxide synthase (NOS; EC 1.14.13.39). Simple treatment of quiescent sperm with an NO donor (SNAP or NOC7) in vitro did not lead to activation of motility. Nevertheless, initiatorin- or trypsin-induced motility was blocked by pretreatment of sperm with either the NOS inhibitor L-NAME or NO scavenger carboxy-PTIO. These observations suggested that NO may play important physiological roles in the acquisition of sperm motility under the in vitro condition used here. Then, we investigated whether NO synthesis would occur in the spermatophore, a capsule containing spermatozoa that is created by the contents of various male reproductive glands and is the site of sperm maturation. The amounts of NO2- and NO3-, stable metabolites of NO, reached maximum values after enclosure in the spermatophore, a time when apyrene spermatozoa acquire vigorous motility. Moreover, RT-PCR and Western blotting analyses of NOS indicated that it is abundantly expressed in glandula (g.) lacteola of the virgin male ejaculatory duct, from which it is secreted to the seminal fluid and transferred to the female during mating. Previous studies demonstrated that free L-arginine is supplied de novo by a specific proteolytic reaction in which initiatorin participates during spermatophore formation (Osanai et al., 1987c). Based on these results, it can be presumed that the mixing of seminal fluid contents from each male reproductive organ during ejaculation induced NO production outside of the spermatid, and exogenous NO stimulated a signaling pathway involved in the activation of silkworm apyrene sperm.


Asunto(s)
Bombyx/fisiología , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico/metabolismo , Motilidad Espermática , Animales , Femenino , Masculino , NG-Nitroarginina Metil Éster , Nitratos/metabolismo , Nitritos/metabolismo , S-Nitroso-N-Acetilpenicilamina , Semen/enzimología , Transducción de Señal , Espermatogonias/metabolismo , Triazenos
9.
Micromachines (Basel) ; 8(12)2017 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-30400543

RESUMEN

A robust pick and placement operation of a single cell is necessary for efficient sample collection. Detection and manipulation of single cells requires minimum invasiveness. We report a less-invasive method for picking up and placing single cells using optical and electrical observations for robust cell manipulation. We measured the ionic current through a glass pipette during a cell capture and release operation to detect its capture. Trapping a cell on the pipette tip by suction decreased the current and allowed the detection of cell capture within 1 s. A time-series ionic current was sensitive to the location of a cell and effective at detecting a single cell. A time-series ionic current had a higher signal-to-noise ratio than time-series microscope images. Cell membrane integrity was analyzed at the different capturing and voltage conditions. Serum protein coating shows improvement of a cell release from a pipette tip. Measurement of trajectory and distance of a cell reveals that the movement depends on an ejection flow and the flow in a dish. We achieved a pick-up and placement operation for single cells that was compatible with an open-top microwell while performing observations using optical microscopy and measurements using an electrical current.

10.
Breed Sci ; 67(5): 466-471, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29398940

RESUMEN

Preharvest sprouting (PHS) of durum wheat (Triticum turgidum ssp. durum (Desf.) Husn.) is an important problem in Japan, where the rainy season overlaps with the harvest season. Since there are few PHS-resistant genetic resources in durum wheat, we introduced an R-gene for red seeds, the MFT gene, and the QPhs-5AL QTL, all of which are associated with PHS resistance, into durum wheat from a PHS-resistant bread wheat (T. aestivum L.) cultivar, 'Zenkoujikomugi' (Zen), by backcross breeding. Developed near isogenic lines (NILs) with red seeds had a lower percentage germination (PG) and germination index (GI) than the recurrent parent, and seed color had the greatest effect. A NIL combining all three sequences had the lowest GI and PG, with a similar GI to that of 'Shiroganekomugi' bread wheat. Among NILs with white seeds, a NIL combining MFT and QPhs-5AL had the lowest GI and PG. As the combination of all three sequences from Zen conferred PHS resistance on durum wheat, PHS-resistant genetic resources in bread wheat can be used in breeding durum wheat.

11.
Biomed Microdevices ; 17(2): 41, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25749639

RESUMEN

Parallel manipulation of single cells is important for reconstructing in vivo cellular microenvironments and studying cell functions. To manipulate single cells and reconstruct their environments, development of a versatile manipulation tool is necessary. In this study, we developed an array of hollow probes using microelectromechanical systems fabrication technology and demonstrated the manipulation of single cells. We conducted a cell aspiration experiment with a glass pipette and modeled a cell using a standard linear solid model, which provided information for designing hollow stepped probes for minimally invasive single-cell manipulation. We etched a silicon wafer on both sides and formed through holes with stepped structures. The inner diameters of the holes were reduced by SiO2 deposition of plasma-enhanced chemical vapor deposition to trap cells on the tips. This fabrication process makes it possible to control the wall thickness, inner diameter, and outer diameter of the probes. With the fabricated probes, single cells were manipulated and placed in microwells at a single-cell level in a parallel manner. We studied the capture, release, and survival rates of cells at different suction and release pressures and found that the cell trapping rate was directly proportional to the suction pressure, whereas the release rate and viability decreased with increasing the suction pressure. The proposed manipulation system makes it possible to place cells in a well array and observe the adherence, spreading, culture, and death of the cells. This system has potential as a tool for massively parallel manipulation and for three-dimensional hetero cellular assays.


Asunto(s)
Ingeniería Biomédica/métodos , Análisis de la Célula Individual/instrumentación , Supervivencia Celular , Diseño de Equipo , Células HeLa , Humanos , Dióxido de Silicio/química , Análisis de la Célula Individual/métodos
12.
Phytochemistry ; 113: 33-40, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-24947336

RESUMEN

The purine permeases (PUPs) constitute a large plasma membrane-localized transporter family in plants that mediates the proton-coupled uptake of nucleotide bases and their derivatives, such as adenine, cytokinins, and caffeine. A Nicotiana tabacum (tobacco) PUP-family transporter, nicotine uptake permease 1 (NtNUP1), was previously shown to transport tobacco alkaloids and to affect both nicotine biosynthesis and root growth in tobacco plants. Since Arabidopsis PUP1, which belongs to the same subclade as NtNUP1, was recently reported to transport pyridoxine and its derivatives (vitamin B6), it was of interest to examine whether NtNUP1 could also transport these substrates. Direct uptake measurements in the yeast Saccharomyces cerevisiae demonstrated that NtNUP1 efficiently promoted the uptake of pyridoxamine, pyridoxine, anatabine, and nicotine. The naturally occurring (S)-isomer of nicotine was preferentially transported over the (R)-isomer. Transport studies using tobacco BY-2 cell lines overexpressing NtNUP1 or PUP1 showed that NtNUP1, similar to PUP1, transported various compounds containing a pyridine ring, but that the two transporters had distinct substrate preferences. Therefore, the previously reported effects of NtNUP1 on tobacco physiology might involve bioactive metabolites other than tobacco alkaloids.


Asunto(s)
Alcaloides/metabolismo , Nicotiana/metabolismo , Proteínas de Transporte de Nucleobases/metabolismo , Piridinas/metabolismo , Vitamina B 6/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Piridoxamina/metabolismo , Piridoxina/metabolismo , Saccharomyces cerevisiae/genética , Nicotiana/química
13.
Plant Physiol ; 166(4): 2195-204, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25344505

RESUMEN

The down-regulation of a tobacco (Nicotiana tabacum) plasma membrane-localized nicotine uptake permease, NUP1, was previously reported to reduce total alkaloid levels in tobacco plants. However, it was unclear how this nicotine transporter affected the biosynthesis of the alkaloid nicotine. When NUP1 expression was suppressed in cultured tobacco cells treated with jasmonate, which induces nicotine biosynthesis, the NICOTINE2-locus transcription factor gene ETHYLENE RESPONSE FACTOR189 (ERF189) and its target structural genes, which function in nicotine biosynthesis and transport, were strongly suppressed, resulting in decreased total alkaloid levels. Conversely, NUP1 overexpression had the opposite effect. In these experiments, the expression levels of the MYC2 transcription factor gene and its jasmonate-inducible target gene were not altered. Inhibiting tobacco alkaloid biosynthesis by suppressing the expression of genes encoding enzymes in the nicotine pathway did not affect the expression of ERF189 and other nicotine pathway genes, indicating that ERF189 is not regulated by cellular alkaloid levels. Suppressing the expression of jasmonate signaling components in cultured tobacco cells showed that NUP1 acts downstream of the CORONATINE INSENSITIVE1 receptor and MYC2, but upstream of ERF189. These results suggest that although jasmonate-activated expression of MYC2 induces the expression of both NUP1 and ERF189, expression of ERF189 may actually be mediated by NUP1. Furthermore, NUP1 overexpression in tobacco plants inhibited the long-range transport of nicotine from the roots to the aerial parts. Thus, NUP1 not only mediates the uptake of tobacco alkaloids into root cells, but also positively controls the expression of ERF189, a key gene in the biosynthesis of these alkaloids.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Nicotiana/enzimología , Nicotina/metabolismo , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Aminoácidos/metabolismo , Transporte Biológico , Membrana Celular/metabolismo , Células Cultivadas , Ciclopentanos/farmacología , Regulación hacia Abajo , Etilenos/metabolismo , Indenos/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Oxilipinas/farmacología , Proteínas de Plantas/genética , Raíces de Plantas/enzimología , Raíces de Plantas/genética , Nicotiana/genética , Factores de Transcripción/genética
14.
Genome Announc ; 2(1)2014 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-24504001

RESUMEN

Lactobacillus namurensis Chizuka 01 was isolated from nukadoko, which is a fermented rice bran bed traditionally used in Japan for pickling vegetables. Here, we report the first draft of an annotated genome sequence of this organism. This paper is the first published report of the genomic sequence of L. namurensis.

15.
Plant Cell Physiol ; 55(2): 436-44, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24287136

RESUMEN

Biosynthesis of nicotine in tobacco requires N-methylputrescine oxidase (MPO), which belongs to the copper-containing amine oxidase superfamily. Previous studies identified tobacco MPO1 and its close homolog NtDAO1 (formerly called MPO2), of which MPO1 has been shown preferentially to oxidize N-methylated amines. We show here that NtDAO1, as well as a homologous Arabidopsis diamine oxidase (DAO), accept non-N-methylated amines more efficiently than their corresponding N-methylated amines. MPO1 is coordinately regulated with other nicotine biosynthesis genes with regard to COI1-MYC2-dependent jasmonate induction and its dependence on nicotine-specific ERF transcription factors, whereas NtDAO1 is constitutively expressed at low basal levels in tobacco plants. Both MPO1 and NtDAO1 are targeted to peroxisomes by their C-terminal motifs, and the peroxisomal localization of MPO1 is required for it to function in nicotine biosynthesis in jasmonate-elicited cultured tobacco cells. Restricted occurrence of the MPO subfamily in Nicotiana and Solanum indicates that, during the formation of the Solanaceae, MPO has evolved from a DAO, which functions in polyamine catabolism within peroxisomes, by optimizing substrate preference and gene expression patterns to be suitable for alkaloid formation.


Asunto(s)
Amina Oxidasa (conteniendo Cobre)/genética , Arabidopsis/enzimología , Regulación de la Expresión Génica de las Plantas , Nicotiana/enzimología , Putrescina/metabolismo , Alcaloides/análisis , Alcaloides/metabolismo , Amina Oxidasa (conteniendo Cobre)/metabolismo , Arabidopsis/citología , Arabidopsis/genética , Ciclopentanos/metabolismo , Evolución Molecular , Modelos Biológicos , Nicotina/metabolismo , Oxilipinas/metabolismo , Peroxisomas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Hojas de la Planta/citología , Hojas de la Planta/enzimología , Hojas de la Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/citología , Raíces de Plantas/enzimología , Raíces de Plantas/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Transporte de Proteínas , Interferencia de ARN , Proteínas Recombinantes , Especificidad por Sustrato , Nicotiana/citología , Nicotiana/genética
16.
Chemosphere ; 89(4): 378-82, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22732300

RESUMEN

We developed a novel polymer type sulfoxide-modified solid phase enabling to achieve selective separation of polychlorinated biphenyls (PCBs) from insulation oil. In this study, firstly we prepared base-polymer based on the concept of the molecular imprinting to capture PCBs in selectively, then, the sulfoxide groups were modified on the pore surface of base-polymers by changing preparation methods. As results of liquid chromatographic analyses for the polymers as columns, the base-polymer prepared by xylene as a porogenic solvent showed selective retention ability for chlorinated aromatic compounds by the porogen imprinting effect. Additionally, the polymer-type sulfoxide solid phases showed highly retention ability for PCBs by increasing amount of introduced sulfoxide groups. Consequently, the results of separation of PCBs comparing to insulation oil suggested that the prepared solid phase can be used for the selective separation of PCBs at the same level as a commercially available media utilized for the regulated method.


Asunto(s)
Aceites Industriales/análisis , Aceite Mineral/análisis , Bifenilos Policlorados/análisis , Extracción en Fase Sólida/métodos , Sulfóxidos/química , Cromatografía Liquida , Impresión Molecular , Polímeros/síntesis química , Solventes/química , Espectroscopía Infrarroja por Transformada de Fourier , Xilenos/química
17.
J Sep Sci ; 34(16-17): 2193-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21674793

RESUMEN

We report the fundamental chromatographic retention properties of spongy monolith that was previously reported as a novel separation medium for the effective pretreatment of environmental pollutants. According to the detailed examination on liquid chromatographic evaluations using hydrophobic, hydrophilic, and polyaromatic compounds as solutes, the spongy monolith consisted of poly(ethylene-co-vinyl acetate) and having macroporous co-continuous structures showed the selective retention ability for polyaromatic hydrocarbons (PAHs), especially coplanar compounds, whereas lower selectivity was observed for typical hydrophobic and hydrophilic compounds compared with the commonly used C18 medium. Moreover, we demonstrate the effective preconcentration of benzo[a]pyrene using a spongy monolith as a pretreatment column of an online column switching HPLC system.

18.
Phys Chem Chem Phys ; 12(39): 12570-7, 2010 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-20730133

RESUMEN

The film structure and electronic structure of a biradical hydrocarbon, diphenyl derivative of s-indacenodiphenalene (Ph(2)-IDPL) solid film has been investigated. A small energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) compared with that of typical π-conjugated small molecules was observed even for the amorphous film of Ph(2)-IDPL. This result indicates that the small HOMO-LUMO gap is an important characteristic of the singlet biradical electronic structure and well explains the previously reported ambipolar field effects of amorphous Ph(2)-IDPL film by Chikamatsu et al., Appl. Phys. Lett. 2007, 91, 043506. It was found that the gas-deposition method substantially improved the crystallinity of the film where Ph(2)-IDPL molecules form quasi one-dimensional (1D) molecular chains normal to the substrate surface. An extremely small HOMO-LUMO gap was observed in the polycrystalline Ph(2)-IDPL film, which is possibly caused by strong intermolecular coupling. The photon energy dependence of ultraviolet photoemission spectra shows that the stacked Ph(2)-IDPL molecular chain in the polycrystalline film develops an energy band structure in the direction of the surface normal of the film. The intermolecular covalency therefore evolves into the quasi 1D energy band along the molecular stacking direction.

19.
Biol Pharm Bull ; 32(10): 1741-8, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19801837

RESUMEN

Processed aconite root (PA) is a crude drug used in traditional Chinese or Japanese medicine to generate heat in interior body and dispel cold. We evaluated the effects of PA on hypothermia and reduction in the activity of natural killer (NK) cells in mice exposed to chronic cold stress. Male mice were reared at 4 degrees C, and powdered PA was administered for 10 d as a food additive. Core body temperature of mice significantly decreased by approximately 1 degrees C after rearing in a cold environment, and PA administration significantly restored the reduction in core body temperature in a dose-dependent manner. After 10 d, splenic NK-cell activity of cold-stressed mice was significantly reduced, and the reduction was dose-dependently recovered by PA administration. An aconitine-type alkaloid fraction prepared from PA was ineffective when administered to cold-stressed mice, and the thermogenic effect on hypothermic mice was present in the fraction containing low-molecular-weight compounds without alkaloids. In cold-stressed mice, the weight of brown adipose tissue (BAT) and uncoupling protein (UCP)-1 level in BAT increased, whereas the weight of white adipose tissue decreased. The increase in UCP-1 level in BAT of cold-stressed mice was further augmented by PA treatment. These results indicate that PA exhibited a thermogenic effect on hypothermia induced by cold stress in mice by additional upregulation of UCP-1 level in BAT, which was already enhanced by hypothermia, and that the active ingredients present in PA are non-alkaloidal low-molecular-weight compounds.


Asunto(s)
Aconitum/química , Hipotermia/tratamiento farmacológico , Células Asesinas Naturales/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Termogénesis/efectos de los fármacos , Tejido Adiposo/efectos de los fármacos , Alcaloides/farmacología , Alcaloides/uso terapéutico , Animales , Frío , Relación Dosis-Respuesta a Droga , Hipotermia/inmunología , Hipotermia Inducida/métodos , Canales Iónicos/metabolismo , Células Asesinas Naturales/metabolismo , Masculino , Ratones , Ratones Endogámicos , Proteínas Mitocondriales/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Extractos Vegetales/farmacología , Raíces de Plantas , Recalentamiento/métodos , Bazo/efectos de los fármacos , Bazo/inmunología , Estrés Fisiológico/efectos de los fármacos , Proteína Desacopladora 1
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