Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Physiol Pharmacol ; 72(2)2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34374659

RESUMO

The Asian ginseng root (Panax ginseng C.A. Meyer) is a very commonly used herbal medicine worldwide. Ginseng fruit, including the berry (or pulp) and seed, is also valuable for several health conditions including immunostimulation and cancer chemoprevention. In this study, the anticancer and anti-proliferative effects of the extracts of ginseng berry and seed were evaluated. The ginsenosides in the ginseng berry concentrate (GBC) and ginseng seed extract (GSE) were analyzed. We then evaluated their anti-colorectal cancer potentials, including antiproliferation, cell cycle arrest, and apoptotic induction. Further investigation consisted of the berry's adaptive immune responses, such as the actions on the differentiation of T helper cells Treg, Th1, and Th17. The major constituents in GBC were ginsenosides Re and Rd, which can be compared to those in the root. The GBC significantly inhibited colon cancer cell growth, and its anti-proliferative effect involved mechanisms including G2/M cell cycle arrest via upregulation of cyclin A and induction of apoptosis via regulation of apoptotic related gene expressions. GBC also downregulated the expressions of pro-inflammatory cytokine genes. For the adaptive immune responses, GBC did not influence Th1 and Treg cell differentiation but significantly inhibited Th17 cell differentiation and thus regulated the balance of Th17/Treg for adaptive immunity. Although no ginsenoside was detected in the GSE, interestingly, it obviously enhanced colon cancer cell proliferation with the underlined details to be determined. Our results suggested that GBC is a promising dietary supplement for cancer chemoprevention and immunomodulation.


Assuntos
Neoplasias do Colo , Panax , Apoptose , Ciclo Celular , Diferenciação Celular , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/prevenção & controle , Medicamentos de Ervas Chinesas , Frutas , Humanos , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle , Extratos Vegetais/farmacologia
2.
Ticks Tick Borne Dis ; 11(4): 101388, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32122808

RESUMO

In north-western Europe, the common tick, Ixodes ricinus, is widely established, its distribution appears to be increasing and the spread of tick-borne diseases is of increasing concern. The project 'Flått i Nord' (Ticks in northern Norway) commenced in spring 2009 with the intention of studying the tick's distribution and that of its pathogens in northern Norway. Several methods were used: cloth-dragging, collecting from trapped small mammals, and collecting from pets. Since 2010, the occurrence of ticks in the region of northern Norway was determined directly by cloth-dragging 167 times in 109 separate locations between the latitudes of 64 °N and 70 °N (included seven locations in the northern part of Trøndelag County). The northernmost location of a permanent I. ricinus population was found to be Nordøyvågen (66.2204 °N, 12.59 °E) on the Island of Dønna. In a sample of 518 nymphal and adult ticks, the Borrelia prevalence collected close to this distribution limit varied but was low (1-15 %) compared with the locations in Trøndelag, south of the study area (15-27 %). Five specimens (1 %) were positive for Rickettsia helvetica. The length of the vegetation growing season (GSL) can be used as an approximate index for the presence of established populations of I. ricinus. The present study suggests that the threshold GSL for tick establishment is about 170 days, because the median GSL from 1991 to 2015 was 174-184 days at sites with permanent tick populations, showing a clear increase compared with the period 1961-1990. This apparent manifestation of climate change could explain the northward extension of the range of I. ricinus.


Assuntos
Distribuição Animal , Borrelia/isolamento & purificação , Ixodes/microbiologia , Ixodes/fisiologia , Rickettsia/isolamento & purificação , Animais , Feminino , Ixodes/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/microbiologia , Larva/fisiologia , Masculino , Noruega , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Ninfa/fisiologia
3.
Nanoscale Adv ; 2(6): 2448-2461, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-36133367

RESUMO

Localized Surface Plasmon Resonance (LSPR) of noble metal nanoparticles has attracted a lot of attention in recent years as enhancer of the photocatalytic activity in the visible light domain. Rare are the experimental in situ studies, coupling structural and optical responses, but they are mandatory for a deep understanding of the mechanisms underlying LSPR. Herein we present an in situ investigation during the growth of gold nanoparticles (NPs) on TiO2(110) in the 2-6 nm size range. We probed the structural and morphological properties of the supported nanoparticles by performing GIXRD and GISAXS simultaneously with their optical response in p and s polarizations recorded by SDRS. The rutile surface state turns out to have a major effect on the Au NPs growth and on their plasmonic response, both in frequency and vibration modes. The roughening of the TiO2(110) surface weakens the interaction strength between the NPs and the substrate, favoring the growth of textured in-plane randomly orientated NPs. Compared to the epitaxial clusters growing on the flat TiO2 surface, these textured NPs are characterized by a LSPR blue shift and by the presence of LSPR vibration modes perpendicular to the surface for sizes smaller than about 4 nm.

4.
Eur J Clin Microbiol Infect Dis ; 36(11): 2221-2229, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28730535

RESUMO

For laboratory diagnostics of Lyme neuroborreliosis (LNB), the recomBead Borrelia antibody index (AI) assay has shown promising results in a mixed age population, but has not previously been evaluated with specific focus on paediatric patients. The aim of the study was to evaluate the recomBead Borrelia AI assay in cerebrospinal fluid (CSF) for the laboratory diagnosis of LNB in children. We also wanted to explore whether early markers, such as CXCL13 in CSF and/or total IgM index could be useful as complementary diagnostic tools. Children being evaluated for LNB in a Swedish Lyme endemic area were included in the study (n = 146). Serum and CSF were collected on admission. Patients with other specific diagnoses were controls (n = 15). The recomBead Borrelia AI assay and the recomBead CXCL13 assay (Mikrogen) were applied together with total IgM index. The overall sensitivity for recomBead Borrelia AI (IgM and IgG together) was 74% and the specificity was 97%. However, the highest sensitivity (91%) at an acceptable level of specificity (90%) was obtained by recomBead Borrelia AI together with CXCL13 and total IgM index, showing a positive predictive value of 84% and a negative predictive value of 95%. Thus, the recomBead Borrelia AI assay performs with moderate sensitivity and high specificity in paediatric LNB patients. The major advantage seems to be increased sensitivity in the possible LNB group compared to the IDEIA assay. The diagnostic sensitivity may be further increased by using a combination of early markers, such as CXCL13 in CSF and total IgM index.


Assuntos
Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/líquido cefalorraquidiano , Grupo Borrelia Burgdorferi/imunologia , Quimiocina CXCL13/líquido cefalorraquidiano , Imunoglobulina G/sangue , Imunoglobulina G/líquido cefalorraquidiano , Imunoglobulina M/sangue , Imunoglobulina M/líquido cefalorraquidiano , Neuroborreliose de Lyme/diagnóstico , Adolescente , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Criança , Pré-Escolar , Técnicas de Laboratório Clínico/métodos , Feminino , Humanos , Neuroborreliose de Lyme/microbiologia , Masculino , Sensibilidade e Especificidade
5.
Faraday Discuss ; 152: 253-65; discussion 293-306, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22455049

RESUMO

The relationship between the catalytic activity and the size was studied in operando in the case of gold nanoparticles on TiO2(110) model catalyst during carbon monoxide oxidation. The geometrical parameters, the shape and the dispersion of the particles on the oxide support were examined in detail. The catalytic activity was found optimum for a nanoparticle diameter of about 2 nm and a height of six atomic monolayers. Above the maximum, it fits a power law of the diameter D(-24 +/- 0.3). This indicates that the low-coordinated sites play a major role in the catalytic activity, however such a model still fails to explain the activity maximum. The nanoparticle sintering was also investigated since it is suspected of being responsible for the decrease of the catalyst activity in the course of time. It was clearly observed for particles with a size around the maximum of activity and smaller. At the very beginning of the CO conversion into CO2, the sintering is strongly activated. The nanoparticles mobility is dependent upon the TiO2(110) surface direction under consideration: it is higher along the [001]TiO2 than along the [1-10]TiO2. Then, the sintering greatly slows down. This could be explained by a nanoparticles' pinning at the step edges. The thermal energy released by the exothermic CO oxidation reaction was evaluated and it suggests that the sintering results from a more complex process than from a reaction-induced local heating.

6.
Rev Sci Instrum ; 78(8): 083902, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17764330

RESUMO

A new experimental setup has been developed to enable in situ studies of catalyst surfaces during chemical reactions by means of surface x-ray diffraction (SXRD) and grazing incidence small angle x-ray scattering. The x-ray reactor chamber was designed for both ultrahigh-vacuum (UHV) and reactive gas environments. A laser beam heating of the sample was implemented; the sample temperature reaches 1100 K in UHV and 600 K in the presence of reactive gases. The reactor equipment allows dynamical observations of the surface with various, perfectly mixed gases at controlled partial pressures. It can run in two modes: as a bath reactor in the pressure range of 1-1000 mbars and as a continuous flow cell for pressure lower than 10(-3) mbar. The reactor is connected to an UHV preparation chamber also equipped with low energy electron diffraction and Auger spectroscopy. This setup is thus perfectly well suited to extend in situ studies to more complex surfaces, such as epitaxial films or supported nanoparticles. It offers the possibility to follow the chemically induced changes of the morphology, the structure, the composition, and growth processes of the model catalyst surface during exposure to reactive gases. As an example the Pd(8)Ni(92)(110) surface structure was followed by SXRD under a few millibars of hydrogen and during butadiene hydrogenation while the reaction was monitored by quadrupole mass spectrometry. This experiment evidenced the great sensitivity of the diffracted intensity to the subtle interaction between the surface atoms and the gas molecules.


Assuntos
Espalhamento a Baixo Ângulo , Manejo de Espécimes/instrumentação , Difração de Raios X/instrumentação , Catálise , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Manejo de Espécimes/métodos , Propriedades de Superfície , Difração de Raios X/métodos
7.
Phys Rev Lett ; 89(14): 146106, 2002 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-12366060

RESUMO

The structure of a four monolayer deposit of Pd on Ni(110) has been determined by a combination of x-ray diffraction experiments and density-functional theory calculations. This Pd film presents, after annealing at 500 K, a (Nx2) reconstruction associated with a large enhancement of its catalytic activity. The N superstructure, along the dense [11;0] direction, comes from periodic edge dislocations initiated by a vacancy in the first Pd layer. In the perpendicular direction, the doubling of the period originates in a pairing-buckling displacement of the rows. This study evidences a new Pd atoms arrangement with quasi-four-fold hollow sites on the surface, which could play an important role in the exceptional catalytic activity.

8.
Genomics ; 3(4): 380-4, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2907504

RESUMO

The gene coding for a Na+,K+-ATPase alpha subunit (ATP1A3) has been localized to the q12----q13.2 region of human chromosome 19, potentially close to the myotonic dystrophy (DM) gene. In view of previous studies implicating a Na+,K+-ATPase in the pathology of DM, we have examined the possibility that ATP1A3 is a candidate for the DM locus. Although linked, several clear instances of recombination between ATP1A3 and DM rule out the possibility that mutations in ATP1A3 cause the disease. Examination of multiply informative pedigrees indicates the gene order DM-APOC2-ATP1A3.


Assuntos
Cromossomos Humanos Par 19 , Genes , Ligação Genética , Distrofia Miotônica/genética , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , ATPase Trocadora de Sódio-Potássio/genética , Animais , Mapeamento Cromossômico , Sondas de DNA , Desoxirribonucleases de Sítio Específico do Tipo II , Feminino , Humanos , Células Híbridas/citologia , Substâncias Macromoleculares , Masculino , Linhagem
9.
Genomics ; 3(2): 124-8, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2906322

RESUMO

A restriction fragment length polymorphism (RFLP) at the human FGR gene, a member of the src family of protooncogenes, has been identified and used to locate FGR on the genetic linkage map of human chromosome 1p. Single-copy sequences subcloned from a cosmid containing the human FGR gene were used to screen a panel of genomic DNAs for RFLPs. One plasmid, designated pB8, detected a high-frequency EcoRI RFLP (allele frequencies, 0.57/0.43). Analysis of a panel of somatic cell hybrids demonstrated that pB8 maps to the region 1p31-pter. Genetic linkage analysis of the 40 families provided by the Centre d'Etude du Polymorphisme Humain (CEPH) showed that FGR maps to a location 3.1 cM from the Rh blood group locus (RH), and falls in the 17.5-cM gap between alpha-fucosidase (FUCA1) and D1S57. The relative gene order of RH and FGR could not be determined unequivocally, but the most favored gene order was 1pter-PND-ALPL-FUCA1-FGR-RH-D1S57-MYCL.


Assuntos
Cromossomos Humanos Par 1 , Ligação Genética , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Proto-Oncogenes , Alelos , Mapeamento Cromossômico , Enzimas de Restrição do DNA , Humanos , Hibridização de Ácido Nucleico
10.
J Biol Chem ; 259(22): 13980-5, 1984 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-6094534

RESUMO

The nucleotide sequence of the HindIII-D fragment of adenovirus type 2 has been determined. The sequence, which is located between coordinates 41.8 and 51.0, covers most of the L2 cotermination family. It includes three major open translational reading frames encoding the carboxyl-terminal part of the penton base as well as the major core polypeptides V and VII. An additional minor open translational reading frame encoding a highly basic polypeptide was detected in the sequence. The L2 region has a very compact organization with very short distances between the different genes, although no overlapping coding sequences were found. The predicted amino acid sequences of core proteins V and VII reveal that they are highly basic proteins and polypeptide VII resembles the arginine-rich H4 histones in its amino acid composition, but no striking similarities are apparent at the amino acid sequence level. The candidate polypeptide encoded by the newly discovered translational reading frame contains 29% basic residues and includes a hypothetical recognition sequence for the adenovirus-encoded endopeptidase. In conjunction with previously published sequences and those reported in accompanying papers (Akusjärvi, G., Aleström, P., Pettersson, M., Lager, M., Jörnvall, H., and Pettersson, U. (1984) J. Biol. Chem. 259, 13976-13979; Roberts, R. J., O'Neill, K. E., and Yen, C. E. (1984) J. Biol. Chem. 259, 13965-13975) a complete sequence can now be reconstructed for the 35,937-base pairs adenovirus type 2 genome.


Assuntos
Adenovírus Humanos/genética , DNA Viral/análise , Proteínas Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Enzimas de Restrição do DNA/metabolismo , Desoxirribonuclease HindIII , Endonucleases/metabolismo , Conformação de Ácido Nucleico , Endonucleases Específicas para DNA e RNA de Cadeia Simples , Proteínas do Core Viral , Proteínas Virais/análise
11.
J Biol Chem ; 259(22): 13976-9, 1984 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-6501284

RESUMO

The nucleotide sequence of the gene for the adenovirus type 2 hexon has been determined. The hexon polypeptide consists of 967 amino acid residues and has a molecular weight of 109,058. Several tentative parts in the previously reported amino acid sequence were resolved from the DNA sequence. The existence of regions with unusual properties in the hexon protein was confirmed, including a region consisting of 16 consecutive acidic residues in the N-terminal part of the protein. In conjunction with previously published sequences and sequences reported in the accompanying papers (Aleström, P., Akusjärvi, G., Lager, M., Yeh-Kai, L., and Petterson, U. (1984) J. Biol. Chem. 259, 13980-13985; Roberts, R. J., O'Neill, K. E., and Yen, C. E. (1984) J. Biol. Chem. 259, 13965-13975) a complete sequence of the 35,937-base pairs-long adenovirus type 2 genome can now be reconstructed.


Assuntos
Adenovírus Humanos/genética , Proteínas do Capsídeo , Capsídeo/genética , DNA Viral/análise , Sequência de Aminoácidos , Sequência de Bases , Capsídeo/análise , Brometo de Cianogênio , Fragmentos de Peptídeos/análise , RNA Mensageiro/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...