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1.
Sensors (Basel) ; 21(21)2021 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-34770693

RESUMEN

Phased array technology features rapid and directional scanning and has become a promising approach for remote sensing and wireless communication. In addition, element-level digitization has increased the feasibility of complicated signal processing and simultaneous multi-beamforming processes. However, the high cost and bulky characteristics of beam-steering systems have prevented their extensive application. In this paper, an X-band element-level digital phased array radar utilizing fully integrated complementary metal-oxide-semiconductor (CMOS) transceivers is proposed for achieving a low-cost and compact-size digital beamforming system. An 8-10 GHz transceiver system-on-chip (SoC) fabricated in 65 nm CMOS technology offers baseband filtering, frequency translation, and global clock synchronization through the proposed periodic pulse injection technique. A 16-element subarray module with an SoC integration, antenna-in-package, and tile array configuration achieves digital beamforming, back-end computing, and dc-dc conversion with a size of 317 × 149 × 74.6 mm3. A radar demonstrator with scalable subarray modules simultaneously realizes range sensing and azimuth recognition for pulsed radar configurations. Captured by the suggested software-defined pulsed radar, a complete range-azimuth figure with a 1 km maximum observation range can be displayed within 150 ms under the current implementation.

2.
Curr Med Sci ; 38(1): 107-114, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30074159

RESUMEN

Low-temperature plasma (LTP) has shown great promise in wound healing, although the underlying mechanism remains poorly understood. In the present study, an argon atmospheric pressure plasma jet was employed to treat L929 murine fibroblasts cultured in vitro and skin wounds in BALB/c mice. The in vitro analysis revealed that treatment of fibroblasts with LTP for 15 s resulted in a significant increase in cell proliferation, secretion of epidermal growth factor (EGF) and transforming growth factor-ßi (TGF-ßi), production of intracellular reactive oxygen species (ROS), and the percentage of cells in S phase, protein expression of phosphorylated p65 (P-p65) and cyclinD1, but a noted decrease in the protein expression of inhibitor kappa B (IκB). The in vitro experiments demonstrated that 30-s LTP treatment enhanced the number of fibroblasts and the ability of collagen synthesis, while 50-s treatment led to the opposite outcomes. These results suggested that LTP treatment promotes the fibroblast proliferation in wound healing by inducing the generation of ROS, upregulating the expression of P-p65, downregulating the expression of IκB, and activating the NF-κB signaling pathway and consequently altering cell cycle progression (increased DNA synthesis in S phage).


Asunto(s)
Proliferación Celular , Fibroblastos/efectos de los fármacos , Gases em Plasma/farmacología , Transducción de Señal , Cicatrización de Heridas , Animales , Ciclo Celular , Línea Celular , Colágeno/metabolismo , Ciclina D1/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Fibroblastos/fisiología , Ratones , Ratones Endogámicos BALB C , FN-kappa B/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factor de Crecimiento Transformador beta/metabolismo
3.
Oncotarget ; 8(37): 62248-62260, 2017 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-28977942

RESUMEN

Periostin (POSTN, PN, or osteoblast-specific factor OSF-2) is a multifunctional cytokine that signals between the cell and the extracellular matrix. Periostin plays an important role in tumor development and is involved in carcinoma cell epithelial-mesenchymal transition (EMT), whereby mature epithelial cells undergo phenotypic morphological changes and become invasive, motile cells. Here, we discuss the molecular mechanisms involved in periostin-induced promotion of EMT in lung cancer cells. Online TCGA datasets demonstrate the prognostic relevance of periostin in lung cancer; a higher periostin level correlates with poor overall survival. Similarly, our IHC results show that high periostin expression is positively correlated with the EMT markers Snail and Twist, as well as stage of lung cancer. We found that recombinant periostin induces the EMT phenotype in lung cancer cells through the p38/ERK pathway, while pretreatment with chemical inhibitors prevented periostin-induced EMT induction. Moreover, we found that periostin regulates EMT by repressing microRNA-381 (miR-381) expression, which targets both Snail and Twist. Using the miR-381 mimic, we dramatically reversed periostin-induced Snail and Twist expression. Furthermore, periostin knockdown dramatically affected EMT markers and cell migration potential. The role of periostin in lung cancer progression is elucidated by the in vivo mouse model. Our findings indicate that changes in periostin expression in lung cancer may serve as a therapeutic target for the treatment of lung cancer metastasis.

4.
Medicine (Baltimore) ; 96(52): e9485, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29384942

RESUMEN

Lung cancer is one of the most common cancers and is associated with a poor survival rate in the Chinese Han population. Analysis of genetic variants could lead to improvements in prognosis following lung cancer treatment. Resistin (RETN) is an important mediator of metabolic diseases and tumor progression. In this study, we explored the effects of RETN single nucleotide polymorphisms (SNPs) on the susceptibility and clinicopathological characteristics of patients with lung cancer. Four RETN SNPs (rs7408174, rs1862513, rs3745367, and rs3219175) were analyzed using TaqMan SNP genotyping in 371 patients with lung cancer and 451 cancer-free controls. The results showed that the RETN SNP rs3219175 with AG or at least 1 A allele was associated with a higher risk of lung cancer than wild-type (GG) carriers. Moreover, the RETN SNP rs3219175 with AG or AG + AA alleles was associated with a higher risk of distant metastasis than that in patients carrying GG alleles. We also used genotype-tissue expression datasets to compare the correlation of the RETN SNP rs3219175 in lung tissue and whole blood. In conclusion, our study demonstrated, for the first time, that RETN polymorphisms were correlated with lung cancer progression in the Chinese Han population.


Asunto(s)
Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Resistina/genética , Adulto , Factores de Edad , Anciano , Consumo de Bebidas Alcohólicas/epidemiología , Alelos , Pueblo Asiatico , Estudios de Casos y Controles , China/epidemiología , Femenino , Genotipo , Humanos , Neoplasias Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Reacción en Cadena en Tiempo Real de la Polimerasa , Fumar/epidemiología
5.
Sydowia ; 69: 229-264, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29386695

RESUMEN

The present study introduces seven new species, one new combination, one new variety and several interesting taxonomical notes and/or geographical records. Most of the new taxa are Ascomycetes, but the study also includes a new variety of a Basidiomycete. Novel species include Gyromitra khanspurensis (Discinaceae, Pezizales, Pezizomycetes) from Pakistan growing near Cedrus deoadara and Paramyrothecium guiyangense and Paramyrothecium verruridum (Stachybotriaceae, Hypocreales, Sordariomycetes) both isolated from soil in China. New species from South Africa are Sclerostagonospora elegiae on culm litter of Elegia equisetacea, Sclerostagonospora fusiformis on culm litter of Thamnochortus spicigerus, Sclerostagonospora pinguis on culm litter of Cannomois virgata and Sclerostagonospora sulcata on culm litter of Ischyrolepis subverticellata (Phaeosphaeriaceae, Pleosporales, Dothideomycetes). Hapalocystis berkeleyi var. kickxii with its basionym Hypoxylon kickxii is shown to be a taxon on species level and thus recombined as Hapalocystis kickxii (Sydowiellaceae, Diaporthales, Sordariomycetes), and it is lecto- and epitypified. The new variety Pluteus romellii var. luteoalbus (Pluteaceae, Agaricales, Agaricomycetes) growing on a mossy fallen stem of a deciduous tree is described from Czech Republic. Cortinarius scaurocaninus (Cortinariaceae, Agaricales, Agaricomycetes) is new for Austria, Humicola grisea (Chaetomiaceae, Sordariales, Sordariomycetes) is an interesting new record for Chile. Two taxa are reported as new for Turkey: the lichenicolous fungus Opegrapha parasitica (Opegraphaceae, Arthoniales, Arthoniomycetes) growing partly immersed in the thallus of Aspicilia and the lichen Rinodina zwackhiana (Physciaceae, Teloschistales, Lecanoromycetes) from calcareous rock. Finally, Xerula strigosa (Physalacriaceae, Agaricales, Agaricomycetes), described from China, is confirmed to be present also in Pakistan.

6.
J Zhejiang Univ Sci B ; 16(6): 503-10, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26055912

RESUMEN

In cattle, dietary protein is gradually degraded into peptide-bound amino acids (PBAAs), free amino acids (FAAs), and ultimately into ammonia by the rumen microbes. Both PBAA and FAA are milk protein precursors, and the rumen and small intestines are the main sites where such precursors are produced and absorbed. This work was designed to investigate the expression of the peptide transporter PepT1 and the AA transporters ASCT2, y(+)LAT1, and ATB(0,+), and the concentrations of PBAA, FAA, and soluble protein in the rumen, omasum, and duodenum of dairy cows. Tissues and digesta were collected from six healthy Chinese Holstein dairy cows immediately after the animals were slaughtered. The expression of transporters was analyzed by real-time quantitative polymerase chain reaction (PCR). The FAA concentration was assessed using an amino acid (AA) analyzer, PBAA concentration by quantification of AA before and after acid-hydrolysis by 6 mol/L HCl, and soluble protein concentration by quantification of the bicinchoninic acid content. The results showed that the relative abundance of mRNA of the transporters and the soluble non-ammonia nitrogen (SNAN) concentration of each fraction were greater in the duodenum than in the rumen or omasum. These results indicate that the duodenum is the predominant location within the nonmesenteric digestive tract for producing milk protein precursors. In addition, PBAA was the largest component of SNAN in the digesta from the rumen, omasum, and duodenum. In conclusion, the duodenum has the greatest concentrations of SNAN and PBAA, and the greatest potential for absorption of SNAN in the form of PBAA in the nonmesenteric gastrointestinal tissues of dairy cows.


Asunto(s)
Aminoácidos/metabolismo , Bovinos/metabolismo , Duodeno/metabolismo , Absorción Intestinal/fisiología , Nitrógeno/metabolismo , Péptidos/metabolismo , Absorción Fisiológica/fisiología , Aminoácidos/química , Amoníaco/metabolismo , Animales , Duodeno/química , Femenino , Mesenterio/metabolismo , Nitrógeno/química , Péptidos/química , Solubilidad
7.
Am J Respir Cell Mol Biol ; 42(2): 218-26, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19395679

RESUMEN

Myofibroblasts are known to play key roles in wound healing and fibrosis. They are thought to arise de novo from fibroblasts, and are characterized by induction of alpha-smooth muscle actin (alpha-SMA) expression. The homeobox transcription factor Csx/Nkx2.5 is critical in heart development and cardiogenesis by inducing expression of genes associated with cardiomyocyte differentiation. Here, we report a novel repressor activity of Nkx2.5 on myofibroblast differentiation. Because a key marker of myofibroblast differentiation is expression of the alpha-SMA gene, we first scanned its promoter region for possible cis-acting elements. The results show three potential binding sites (designated Nkx2.5 element [NKE]-1, -2, and -3) containing the Nkx2.5/Csx consensus binding motif (5'-TNNAGTG-3'). To determine their functional importance, site-directed mutagenesis directed at these elements individually and in combination indicated that mutation of NKE1 and -3 significantly enhanced alpha-SMA gene promoter activity, whereas mutation of NKE2 did not have a significant effect. The results of gel shift assays confirmed that Nkx2.5 could bind to both NKE1 and -3, but not to NKE2. Consistent with the mutagenesis studies, ectopically induced expression of Nkx2.5 inhibited alpha-SMA gene expression. Analysis of nkx2.5 gene expression indicates that it was significantly induced by basic fibroblast growth factor treatment of isolated lung fibroblasts in vitro. In vivo, lung Nkx2.5 expression was significantly diminished in bleomycin-induced pulmonary fibrosis. These findings are consistent with a novel function for Nkx2.5 as a repressor of alpha-SMA gene transcription, which may be of homeostatic significance as a means of suppressing myofibroblast differentiation in the absence of tissue injury.


Asunto(s)
Fibroblastos/citología , Fibroblastos/metabolismo , Proteínas de Homeodominio/metabolismo , Mioblastos del Músculo Liso/citología , Mioblastos del Músculo Liso/metabolismo , Factores de Transcripción/metabolismo , Actinas/genética , Actinas/metabolismo , Animales , Secuencia de Bases , Sitios de Unión/genética , Bleomicina/toxicidad , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Células Cultivadas , Secuencia de Consenso , ADN/genética , Femenino , Factor 2 de Crecimiento de Fibroblastos/farmacología , Expresión Génica/efectos de los fármacos , Proteína Homeótica Nkx-2.5 , Proteínas de Homeodominio/química , Proteínas de Homeodominio/genética , Técnicas In Vitro , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Regiones Promotoras Genéticas , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/genética , Ratas , Ratas Endogámicas F344 , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homología de Secuencia de Aminoácido , Factores de Transcripción/química , Factores de Transcripción/genética , Transfección
8.
J Zhejiang Univ Sci B ; 9(10): 829-34, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18837112

RESUMEN

Twenty-four soil samples of eight ecosystem-types around the Yellow River source area were investigated for the number and specific composition of soil dematiaceous hyphomycetes by dilution plate technique. And then the co-relationship between genus species of soil dematiaceous hyphomycetes and ecosystem-types was analyzed. The results show that the amount and species distribution of soil dematiaceous hyphomycetes had an obvious variability in different ecosystem-types, and that the dominant genus species varied in the eight ecosystem-types studied, with Cladosporium being the dominant genus in seven of the eight ecosystem-types except wetland. The index of species diversity varied in different ecosystem-types. The niche breadth analysis showed that Cladosporium had the highest niche breadth and distributed in all ecosystem-types, while the genera with a narrow niche breadth distributed only in a few ecosystem-types. The results of niche overlap index analysis indicated that Stachybotrys and Torula, Doratomyces and Scolecobasidium, Cladosporium and Chrysosporium had a higher niche overlap, whereas Arthrinium and Gliomastix, Phialophora and Doratomyces, Oidiodendron and Ulocladium had no niche overlap.


Asunto(s)
Hongos Mitospóricos/clasificación , Hongos Mitospóricos/aislamiento & purificación , Microbiología del Suelo , China , Ecosistema , Agua Dulce/microbiología , Especificidad de la Especie
9.
J Zhejiang Univ Sci B ; 6(8): 793-7, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16052713

RESUMEN

Three yearling lambs with a rumen cannula were used to investigate the effects of supplementation with an urea-minerals lick block (ULB) on the kinetics of ruminal fibre digestion, nutrient digestibility and nitrogen (N) utilization of rice straw (RS), ammonia bicarbonate (AB)treated RS (ABRS) and hay prepared from natural pasture. The digestibility of dry matter and organic matter of RS increased by 13.1% and 12.7% (P<0.05) when the diet was supplemented with ULB, and approached to that of ABRS, indicating that the effect of ULB on digestibility of RS is similar to that of AB treatment. The digestibility of ABRS was slightly improved by the ULB feeding. Nitrogen retention was highest in lambs fed on ABRS alone, followed by hay with ULB, and was lowest in animals fed on RS with ULB. However, both the amount and proportion of N retention to N intake were enhanced by ULB supplementation to lambs fed on hay. The proportion of N retained to N digested decreased due to ULB supplementation to lambs fed on RS or ABRS. Supplementing ULB did not greatly influence the rumen degradation of either dry matter or crude protein in each of the three diets. RS and hay had similar values in the potential extent of digestion (PED) and digestion rate of PED (kd) of fibrous materials, but the discrete lag time for RS was lower than that for hay. The AB treatment significantly increased the PED (P<0.05) and kd (P<0.05) of RS. Neither the PED nor kd for RS and ABRS was influenced by ULB supplementation, but the kd for hay significantly increased due to ULB. The lag time for hay was also shortened by the ULB feeding. The ULB improved the digestion of fibre in the rumen of lambs fed on low quality roughage. It is inferred that while ULB is effective in increasing nutrient digestibility of low quality roughages by improving ruminal fibre digestion. A synchronized supply of N and energy to rumen microbes should be considered to improve the efficiency of N utilization when the basal diet is ammoniated straw.


Asunto(s)
Alimentación Animal , Fibras de la Dieta/metabolismo , Suplementos Dietéticos , Digestión/fisiología , Conducta Alimentaria/fisiología , Ovinos/fisiología , Urea/administración & dosificación , Administración Oral , Animales , Digestión/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Minerales/administración & dosificación , Nitrógeno/metabolismo
10.
J Zhejiang Univ Sci B ; 6(8): 787-92, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16052712

RESUMEN

The effect of tea saponins (TS) on rumen fermentation and methane emission was examined using an in vitro gas production technique named Reading Pressure Technique. Three levels of TS addition (0, 0.2, 0.4 mg/ml) were evaluated in the faunated and defaunated rumen fluid. Compared to the control, TS addition decreased the 24 h gas production in the faunated rumen fluid, but had a minor effect on gas yield in the defaunated rumen fluid. The TS significantly reduced methane production in vitro. In the faunated rumen fluid, 0.2 or 0.4 mg/ml TS decreased the 24 h methane emission by 12.7% or 14.0%, respectively. Rumen fluid pH value was affected neither by TS addition nor by defaunation. The TS addition had only minor effects on volatile fatty acids, but the yield and pattern of volatile fatty acids were greatly affected by defaunation. While the molar proportion of acetate was not affected by defaunation, the propionate was significantly increased and the butyrate significantly decreased. Ammonia-N concentration and microbial protein yield were influenced by TS inclusion and defaunation. Inclusion of 0.4 mg/ml TS increased the microbial protein mass by 18.4% and 13.8% and decreased the ammonia-N concentration by 8.3% and 19.6% in the faunated and defaunated rumen fluid, respectively. Protozoa counts were significantly reduced by TS inclusion. The current study demonstrated the beneficial effect of TS on methane production and rumen fermentation, and indicated that this may be due to the effect of the associated depression on protozoa counts.


Asunto(s)
Camellia sinensis/metabolismo , Eucariontes/fisiología , Contenido Digestivo/efectos de los fármacos , Contenido Digestivo/microbiología , Metano/metabolismo , Rumen/metabolismo , Rumen/microbiología , Saponinas/farmacología , Animales , Eucariontes/efectos de los fármacos , Fermentación/efectos de los fármacos , Técnicas In Vitro , Extractos Vegetales/farmacología , Semillas/metabolismo , Ovinos , Té/química
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