Laccase and Lectin Activities of Intracellular Proteins Produced in a Submerged Culture of the Xylotrophic Basidiomycete Lentinus edodes

The white-rot fungus Lentinus edodes produced D: -melibiose-specific lectins and two laccase forms in a lignin-containing medium. The maxima of laccase and lectin activities coincided, falling within the period of active mycelial growth. The enzymes and lectins were isolated and purified by gel filtration followed by anion-exchange chromatography. The L. edodes lectins were found to be able to stabilize the activity of the fungus's own laccases. Lectin activity during the formation of lectin-enzyme complexes remained unchanged.     

Proteome analysis of bronchoalveolar lavage in lung diseases

The proteomic approach is complementary to genomics and enables protein composition to be investigated under various clinical conditions. Its application to the study of bronchoalveolar lavage (BAL) is extremely promising. BAL proteomic studies were initially based on two-dimensional electrophoretic separation of complex protein samples and subsequent identification of proteins by different methods. With the techniques available today it is possible to attain many different research objectives. BAL proteomics can contribute to the identification of proteins in alveolar spaces with possible insights into pathogenesis and clinical application for diagnosis, prognosis and therapy. Many proteins with different functions have already been identified in BAL. Some could be biomarkers that need to be individually confirmed by correlation with clinical parameters and validation by other methods on larger cohorts of patients. The standardization of BAL sample preparation and processing for proteomic studies is an important goal that would promote and facilitate clinical applications. Here, we review the principal literature on BAL proteomic analysis applied to the study of lung diseases.     

Poly(vinyl amine)-silica composite nanoparticles: models of the silicic acid cytoplasmic pool and as a silica precursor for composite materials formation

The role of polymer (poly(vinylamine)) size (238-11000 units) on silicic acid condensation to yield soluble nanoparticles or composite precipitates has been explored by a combination of light scattering (static and dynamic), laser ablation combined with aerosol spectrometry, IR spectroscopy, and electron microscopy. Soluble nanoparticles or composite precipitates are formed according to the degree of polymerization of the organic polymer and pH. Nanoparticles prepared in the presence of the highest molecular weight polymers have core-shell like structures with dense silica cores. Composite particles formed in the presence of polymers with extent of polymerization below 1000 consist of associates of several polymer-silica nanoparticles. The mechanism of stabilization of the "soluble" silica particles in the tens of nanometer size range involves cooperative interactions with the polymer chains which varies according to chain length and pH. An example of the use of such polymer-poly(silicic acid) nanoparticles in the generation of composite polymeric materials is presented. The results obtained have relevance to the biomimetic design of new composite materials based on silica and polymers and to increasing our understanding of how silica may be manipulated (stored) in the biological environment prior to the formation of stable mineralized structures. We suspect that a similar method of storing silicic acid in an active state is used in silicifying organisms, at least in diatom algae.     

Studies of lipopolysaccharides from Yersinia pseudotuberculosis subtypes VA and VB

Lipopolysaccharides (LPS) from various strains of Yersinia pseudotuberculosis type V have been isolated and characterised. Differences in sugar composition and serological activity of LPS from various strains within the same subtype of Y. pseudotuberculosis have been revealed.     

Patch dynamics of the Mediterranean seagrass Posidonia oceanica: Implications for recolonisation process

Patch dynamics of the Mediterranean slow-growing seagrass Posidonia oceanica was studied in two shallow sites (3–10 m) of the Balearic Archipelago (Spain) through repeated censuses (1–2 year⁻¹). In the sheltered site of Es Port Bay (Cabrera Island), initial patch density (October 2001) was low: 0.05 patches m⁻², and the patch size (number of shoots) distribution was bimodal: most of the patches had less than 6 shoots or between 20 and 50 shoots. Mean patch recruitment in Es Port Bay (0.006 ± 0.002 patches m⁻² year⁻¹) exceeded mean patch loss (0.001 ± 0.001 patches m⁻² year⁻¹), yielding positive net patch recruitment (0.004 ± 0.003 patches m⁻² year⁻¹) and a slightly increased patch density 3 years later (July 2004, 0.06 patches m⁻²). In the exposed site of S’Estanyol, the initial patch density was higher (1.38 patches m⁻², August 2003), and patch size frequency decreased exponentially with size. Patch recruitment (0.26 patches m⁻² year⁻¹) and loss (0.24 patches m⁻² year⁻¹) were high, yielding a slightly increased patch density in the area 1 year later (October 2004, 1.40 patches m⁻²). Most recruited patches consisted of rooting vegetative fragments of 1–2 shoots. Seedling recruitment was observed in Summer 2004 at both sites. Episodic, seedling recruitment comprised 30% and 25% of total patch recruitment in Es Port Bay and S’Estanyol, respectively. Patch survival increased with patch size and no direct removal was observed among patches of 5 shoots or more. Most patches grew along the study, shifting patch distribution towards larger sizes. Within the size range studied (1–150 shoots), absolute shoot recruitment (shoots year⁻¹) increased linearly with patch size (R² = 0.64, p < 4 × 10⁻⁵, N = 125), while specific shoot recruitment was constant (about 0.25 ± 0.05 year⁻¹), although its variance was large for small patches. Given the slow growth rate and the high survival of patches with 5 or more shoots, even the low patch recruitment rates reported here could play a significant role in the colonisation process of P. oceanica.     

Systemic Neurochemical Alterations in Schizophrenic Brain: Glutamate Metabolism in Focus

We have used a systemic approach to establish a relationship between enzyme measures of glial glutamate and energy metabolism (glutamine synthetase and glutamine synthetase-like protein, glutamate dehydrogenase isoenzymes, brain isoform creatine phosphokinase) and two major glial proteins (glial fibrillary acidic protein and myelin basic protein) in autopsied brain samples taken from patients with schizophrenia (SCH) and mentally healthy subjects (23 and 22 cases, respectively). These biochemical parameters were measured in tissue extracts in three brain areas (prefrontal cortex, caudate nucleus, and cerebellum). Significant differences in the level of at least one of the glutamate metabolizing enzymes were observed between two studied groups in all studied brain areas. Different patterns of correlative links between the biochemical parameters were found in healthy and schizophrenic brains. These findings give a new perspective to our understanding of the impaired regulation of enzyme levels in the brain in SCH.     

A shift in sensitivity to auxin within development of maize seedlings

The auxin-induced changes in cytosolic concentrations of Ca(2+) and H(+) ions were investigated in protoplasts from maize coleoptile cells at 3rd, 4th and 5th day of development of etiolated seedlings. The shifts in [Ca(2+)](cyt) and [H(+)](cyt) were detected by use of fluorescence microscopy in single protoplasts loaded with the tetra[acetoxymethyl]esters of the fluorescent calcium binding Fura 2, or pH-sensitive carboxyfluorescein, BCECF, respectively. Both the auxin-induced shifts in the ion concentrations were specific to the physiologically active synthetic auxin, naphthalene-1-acetic acid (1-NAA), and not to the non-active naphthalene-2-acetic acid (2-NAA). Regardless of the age of the seedlings, the rise in [Ca(2+)](cyt) was prior to the acidification in all investigated cases. The maximal acidification coincided with the highest amplitude of [Ca(2+)](cyt) change, but not directly depended on the concentration of 1-NAA. Within aging of the seedlings the amplitude of auxin-induced [Ca(2+)](cyt) elevation decreased. The shift in auxin-induced acidification was almost equal at 3rd and 4th day, but largely dropped at 5th day of development. The acidification was related to changes in the plasma membrane H(+)-ATPase activity, detected as phosphate release. The decrement in amplitude of both the tested auxin-triggered reactions well coincided with the end of the physiological function of the coleoptile. Hence the primary auxin-induced increase in [Ca(2+)](cyt), which is supposed to be an important element of hormone signal perception and transduction, can be used as a test for elucidation of plant cell sensitivity to auxin.     

Patterns of Protozoan Infections: Spatiotemporal Associations with Cattle Density

Waste from cattle production contains protozoa, such as Cryptosporidium spp. and Giardia, which can be transmitted to humans. People residing in areas of high cattle density may be at increased risk for protozoan infections. The objective of this study was to assess spatial and temporal associations between cattle density and hospitalizations for protozoan infections in the U.S. elderly. Data on protozoan infections were abstracted from Centers for Medicare and Medicaid Services datasets for a 14-year period (1991–2004). Cattle inventory data were abstracted from the 2002 U.S. Census of Agriculture. Counties were classified into one of five exposure categories based on both cattle density and human density. Our analyses considered differences in rates, trends, and variations in seasonal patterns based on exposure categories. Cryptosporidiosis demonstrated a trend of increasing annual rates related to increased potential exposure to cattle. Both cryptosporidiosis and giardiasis demonstrated significant seasonal patterns peaking during the fourth week of October in areas of high cattle/low population density and the second week of September in counties with low cattle/low human density, respectively. Counties with low human population density (regardless of cattle density) had the highest rate of all protozoan infections, peaking in the summer. These results demonstrate the elderly population is at increased risk of protozoan infections in areas of high cattle density, particularly cryptosporidiosis. The seasonal patterns and higher annual rates seen in rural areas suggest time-variant environmental exposures, which may be affected with geographical and temporal targeting of agricultural policies and interventions to improve public health.