Search results

Filter

Filetype

Your search for "*" yielded 530186 hits

In vitro self-assembly of the light harvesting pigment-protein LH2 revealed by ultrafast spectroscopy and electron microscopy

Controlled ensemble formation of protein-surfactant systems provides a fundamental concept for the realization of nanoscale devices with self-organizing capability. In this context, spectroscopic monitoring of pigment-containing proteins yields detailed structural information. Here we have studied the association behavior of the bacterial light-harvesting protein LH2 from Rhodobacter spheroides in

Modelling tracer transport by a cumulus ensemble: lateral boundary conditions and large-scale ascent

The vertical transport of tracers by a cumulus ensemble at the TOGA-COARE site is modelled during a 7 day episode using 2-D and 3-D cloud-resolving setups of the Weather Research and Forecast (WRF) model. Lateral boundary conditions (LBC) for tracers, water vapour, and wind are specified and the horizontal advection of trace gases across the lateral domain boundaries is considered. Furthermore, th

N-methyl-D-aspartate receptor-mediated increase of neurogenesis in adult rat dentate gyrus following stroke

Neurogenesis in the adult rat dentate gyrus was studied following focal ischemic insults produced by middle cerebral artery occlusion (MCAO). Animals were subjected to either 30 min of MCAO, which causes damage confined to the striatum, or 2 h of MCAO, which leads to both striatal and cortical infarction. When compared to sham-operated rats, MCAO-rats showed a marked increase of the number of cell

Apolipoprotein D is involved in the mechanisms regulating protection from oxidative stress

Many nervous system pathologies are associated with increased levels of apolipoprotein D (ApoD), a lipocalin also expressed during normal development and aging. An ApoD homologous gene in Drosophila, Glial Lazarillo, regulates resistance to stress, and neurodegeneration in the aging brain. Here we study for the first time the protective potential of ApoD in a vertebrate model organism. Loss of mou

Sertindole: efficacy and safety in schizophrenia

Sertindole is an antipsychotic drug with affinity for dopamine D, serotonin 5-HT2A and 5-HT2C, and alpha(1)-adrenoreceptors. Preclinical studies suggest that sertindole acts preferentially on limbic and cortical dopaminergic neurons and clinical trials have confirmed that sertindole is effective at a low cloparnine D-2 occupancy level. The active substance has a long half-life. Oral administration

Nontangential limits in Pt(µ)-spaces and the index of invariant subgroups

Abstract Let μ be a finite positive measure on the closed disk D¯ in the complex plane, let 1 ≤ t < ∞, and let Pt(μ) denote the closure of the analytic polynomials in Lt(μ). We suppose that D is the set of analytic bounded point evaluations for Pt(μ), and that Pt(μ) contains no nontrivial characteristic functions. It is then known that the restriction of μ to ∂D must be of the form h|dz|. W

Diffuse axonal damage, myelin impairment, astrocytosis and inflammatory response following microinjections of NMDA into the rat striatum

White matter damage and inflammatory response are important secondary outcomes after acute neural disorders. Nevertheless, a few studies addressed the temporal outcomes of these pathological events using non-traumatic models of acute brain injury. In the present study, we describe acute inflammatory response and white matter neuropathology between 1 and 7 days after acute excitotoxic striatal dama

Human immunodeficiency virus (HIV)-2-specific T lymphocyte proliferative responses in HIV-2-infected and in HIV-2-exposed but uninfected individuals in Guinea-Bissau

Human immunodeficiency virus (HIV)-2-specific T lymphocyte proliferative responses were determined in cultures of peripheral blood mononuclear cells from HIV-2-exposed uninfected individuals, HIV-2-infected individuals and HIV-negative controls in Guinea-Bissau. Increased HIV-2-specific T lymphocyte proliferative responses were detected in both groups compared to HIV-negative controls (healthy HIV

Light intensity limits the foraging activity in nocturnal and crepuscular bees.

A crepuscular or nocturnal lifestyle has evolved in bees several times independently, probably to explore rewarding pollen sources without competition and to minimize predation and nest parasites. Despite these obvious advantages, only few bee species are nocturnal. Here we show that the sensitivity of the bee apposition eye is a major factor limiting the ability to forage in dim light. We present

Food selectivity and grazing impact on toxic Dinophysis spp. by copepods feeding on natural plankton assemblages

Food selectivity and grazing impact by Acartia bifilosa, Temora longicornis and Centropages typicus on Dinophysis spp. plankton assemblages were experimentally investigated in the Baltic Sea. Toxin analyses were carried out on phyto- and zooplankton-dominated size fractions from field-collected samples to assess if toxins produced by Dinophysis spp. would end up in the zooplankton. All copepod spe

Data-analysis of pyrolysis-chromatograms by means of simca pattern-recognition

The variability between repetitive pyrolysis—chromatograms of the same type of samples is not totally random, but can in part be modelled by a principal components (PC) model. This makes it possible to use efficiently repetitive pyrolysis-chromatograms of samples of known types to obtain separate PC models for each type. Samples of unknown origin can then be classified according to which of the PC

Agrobacterium tumefaciens as an agent of disease

Twenty-six years ago it was found that the common soil bacterium Agrobacterium tumefaciens is capable of extraordinary feats of interkingdom genetic transfer. Since this discovery, A. tumefaciens has served as a model system for the study of type IV bacterial secretory systems, horizontal gene transfer and bacterial-plant signal exchange. It has also been modified for controlled genetic transforma

Antimicrobial activity of metabolites from mycelial cultures of Chilean Basidiomycetes

We reported seven compounds isolated from mycelial cultures of Chilean Basidiomycetes. The compound structures were elucidated by spectroscopic methods. Two polyacetylenes were isolated from Gymnopilus spectabilis: hepta-4,6-diyn-3-ol (1) and 7-chloro-hepta-4,6-diyn-3 ol (2). We isolated the aromatic compounds p-anisaldehyde (3) and 3-chloro-p-anisaldehyde (4) from Hypholoma capnoides. H. fascicul

Late Holocene environmental change at treeline in the Northern Coast Mountains, British Columbia, Canada

An integrated stratigraphic, paleoecological, and geochronological study of lake and fen sediments just beyond the terminus of Berendon Glacier provides insights into late Holocene climate, vegetation, and glacier change in the northern Coast Mountains of British Columbia. Cores collected from two small lakes in the foreland of Berendon Glacier and pits dug in a nearby fen record Little lee Age an

Storage and voiding symptoms: pathophysiologic aspects.

Lower urinary tract symptoms (LUTS) can be categorized as storage, voiding, and postmicturition symptoms. Although often associated with benign prostatic hyperplasia (BPH), they may also occur in women. This observation, the beneficial effects of a-adrenoceptor (AR) antagonists in men with BPH and LUTS, and the frail correlation between LUTS, and prostatic enlargement and/or outflow obstruction ha