Association of the "major histocompatibility complex subregion" I-J determinant with bioactive glycosylation-inhibiting factor.

Murine suppressor T-cell hybridoma cells (231F1) secrete not only bioactive glycosylation-inhibiting factor (GIF) but also an inactive peptide comparable to bioactive GIF peptide in its molecular size and reactivity with anti-GIF; the amino acid sequence of the inactive peptide is identical to that of the bioactive homologue. The inactive GIF peptide in culture supernatant of both the 231F1 cells and a stable transfectant of human GIF cDNA in the murine suppressor T hybridoma selectively bound to Affi-Gel 10, whereas bioactive GIF peptides from the same sources failed to bind to the gel. The inactive cytosolic human GIF from the stable transfectant and Escherichia coli-derived recombinant human GIF also had affinity for Affi-Gel 10. Both the bioactive murine GIF peptide from the suppressor T hybridoma and bioactive recombinant human GIF from the stable transfectant bound to the anti-I-J monoclonal antibody H6 coupled to Affi-Gel. However, bioactive hGIF produced by a stable transfectant of human GIF cDNA in BMT10 cells failed to be retained in H6-coupled Affi-Gel. These results indicate that the I-J specificity is determined by the cell source of the GIF peptide and that the I-J determinant recognized by monoclonal antibody H6 does not represent a part of the primary amino acid sequence of GIF. It appears that the epitope is generated by a posttranslational modification of the peptide.

Inhibition of function in Xenopus oocytes of the inwardly rectifying G-protein-activated atrial K channel (GIRK1) by overexpression of a membrane-attached form of the C-terminal tail.

Coexpression in Xenopus oocytes of the inwardly rectifying guanine nucleotide binding (G)-protein-gated K channel GIRK1 with a myristoylated modification of the (putative) cytosolic C-terminal tail [GIRK1 aa 183-501 fused in-frame to aa 1-15 of p60src and denoted src+ (183-501)] leads to a high degree of inhibition of the inward G-protein-gated K+ current. The nonmyristoylated segment, src- (183-501), is not active. Although some interference with assembly is not precluded, the evidence indicates that the main mechanism of inhibition is interference with functional activation of the channel by G proteins. In part, the tail functions as a blocking particle similar to a "Shaker ball"; it may also function by competing for the available supply of free G beta gamma liberated by hormone activation of a seven-helix receptor. The non-G-protein-gated weak inward rectifier ROMK1 is less effectively inhibited, and a Shaker K channel was not inhibited. Immunological assays show the presence of a high concentration of src+ (183-501) in the plasma membrane and the absence of any membrane forms for the nonmyristoylated segment.

In vivo estradiol-dependent dephosphorylation of the repressor MDBP-2-H1 correlates with the loss of in vitro preferential binding to methylated DNA.

We have previously shown that estradiol treatment of roosters resulted in a rapid loss of binding activity of the repressor MDBP-2-H1 (a member of the histone H1 family) to methylated DNA that was not due to a decrease in MDBP-2-H1 concentration. Here we demonstrate that MDBP-2-H1 from rooster liver nuclear extracts is a phosphoprotein. Phosphoamino acid analysis reveals that the phosphorylation occurs exclusively on serine residues. Two-dimensional gel electrophoresis and tryptic phosphopeptide analysis show that MDBP-2-H1 is phosphorylated at several sites. Treatment of roosters with estradiol triggers a dephosphorylation of at least two sites in the protein. Phosphatase treatment of purified rooster MDBP-2-H1 combined with gel mobility shift assay indicates that phosphorylation of MDBP-2-H1 is essential for the binding to methylated DNA and that the dephosphorylation can occur on the protein bound to methylated DNA causing its release from DNA. Thus, these results suggest that in vivo modification of the phosphorylation status of MDBP-2-H1 caused by estradiol treatment may be a key step for the down regulation of its binding to methylated DNA.

Ammonia removal using activated carbons: effect of the surface chemistry in dry and moist conditions

The effect of surface chemistry (nature and amount of oxygen groups) in the removal of ammonia was studied using a modified resin-based activated carbon. NH3 breakthrough column experiments show that the modification of the original activated carbon with nitric acid, that is, the incorporation of oxygen surface groups, highly improves the adsorption behavior at room temperature. Apparently, there is a linear relationship between the total adsorption capacity and the amount of the more acidic and less stable oxygen surface groups. Similar experiments using moist air clearly show that the effect of humidity highly depends on the surface chemistry of the carbon used. Moisture highly improves the adsorption behavior for samples with a low concentration of oxygen functionalities, probably due to the preferential adsorption of ammonia via dissolution into water. On the contrary, moisture exhibits a small effect on samples with a rich surface chemistry due to the preferential adsorption pathway via Brønsted and Lewis acid centers from the carbon surface. FTIR analyses of the exhausted oxidized samples confirm both the formation of NH4+ species interacting with the Brønsted acid sites, together with the presence of NH3 species coordinated, through the lone pair electron, to Lewis acid sites on the graphene layers.

Tailoring the porosity of chemically activated hydrothermal carbons: Influence of the precursor and hydrothermal carbonization temperature

Advanced porous materials with tailored porosity (extremely high development of microporosity together with a narrow micropore size distribution (MPSD)) are required in energy and environmental related applications. Lignocellulosic biomass derived HTC carbons are good precursors for the synthesis of activated carbons (ACs) via KOH chemical activation. However, more research is needed in order to tailor the microporosity for those specific applications. In the present work, the influence of the precursor and HTC temperature on the porous properties of the resulting ACs is analyzed, remarking that, regardless of the precursor, highly microporous ACs could be generated. The HTC temperature was found to be an extremely influential parameter affecting the porosity development and the MPSD of the ACs. Tuning of the MPSD of the ACs was achieved by modification of the HTC temperature. Promising preliminary results in gas storage (i.e. CO2 capture and high pressure CH4 storage) were obtained with these materials, showing the effectiveness of this synthesis strategy in converting a low value lignocellulosic biomass into a functional carbon material with high performance in gas storage applications.

Effects of boron on eutectic modification of hypoeutectic Al-Si alloys

The effects of boron on the eutectic modification and solidification mode of hypoeutectic Al-Si alloys have been studied adding different boride phases. The results show that boron does not cause modification of the eutectic silicon. Boron-containing samples display eutectic nucleation and growth characteristics similar to that of unmodified alloys. (C) 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.

Lymphoproliferative disease of the ocular adnexa: A clinical and pathologic study with statistical analysis of 69 patients

Purpose: To evaluate the clinical features, treatment, and outcomes of a cohort of patients with ocular adnexal lymphoproliferative disease classified according to the World Health Organization modification of the Revised European-American Classification of Lymphoid neoplasms and to perform a robust statistical analysis of these data. Methods: Sixty-nine cases of ocular adnexal lymphoproliferative disease, seen in a tertiary referral center from 1992 to 2003, were included in the study. Lesions were classified by using the World Health Organization modification of the Revised European-American Classification of Lymphoid neoplasms classification. Outcome variables included disease-specific Survival, relapse-free survival, local control, and distant control. Results: Stage IV disease at presentation, aggressive lymphoma histology, the presence of prior or concurrent systemic lymphoma at presentation, and bilateral adnexal disease were significant predictors for reduced disease-specific survival, local control, and distant control. Multivariate analysis found that aggressive histology and bilateral adnexal disease had significantly reduced disease-specific Survival. Conclusions: The typical presentation of adnexal lymphoproliferative disease is with a painless mass, swelling, or proptosis; however, pain and inflammation occurred in 20% and 30% of patients, respectively. Stage at presentation, tumor histology, primary or secondary status, and whether the process was unilateral or bilateral were significant variables for disease outcome. In this study, distant spread of lymphoma was lower in patients who received greater than 20 Gy of orbital radiotherapy.

On the tracks of the earliest dinosaurs: implications for the hypothesis of dinosaurian monophyly

From the record of dinosaurian skeletal remains it has been inferred that the origin and initial diversification of dinosaurs were rapid events, occupying an interval of about 5 million years in the Late Triassic. By contrast numerous reports of dinosauroid tracks imply that the emergence of dinosaurs was a more protracted affair extending through much of the Early and Middle Triassic. This study finds no convincing evidence of dinosaur tracks before the late Ladinian. Each of the three dinosaurian clades - Theropoda, Sauropodomorpha, Ornithischia - produced a unique track morphotype that appears to be an independent modification of the chirotherioid pattern attributed to stem-group archosaurs (thecodontian reptiles). The existence of three divergent track morphotypes is consistent with the concept of dinosaurian polyphyly but can be reconciled with the hypothesis of dinosaurian monophyly only by invoking many and rapid reversals in the locomotor anatomy of early dinosaurs. The origin of dinosaurs was not the correlate or consequence of any single event or process, be it global change, competitive replacement, or opportunism in the wake of mass extinction. Instead the origin of dinosaurs is envisaged as a series of three cladogenetic events over an interval of at least 10 million years and possibly as much as 25 million years. This scenario of dinosaurian polyphyly is as well-supported by fossil evidence as is the currently favoured view of dinosaurian monophyly.

A critical analysis of the 'amyloid cascade hypothesis'

The 'amyloid cascade hypothesis' (ACH) is the most influential model of the pathogenesis of Alzheimer's disease (AD). The hypothesis proposes that the deposition of β-amyloid (Aβ) is the initial pathological event in AD, leading to the formation of extracellular senile plaques (SP), tau-immunoreactive neurofibrillary tangles (NFT), neuronal loss, and ultimately, clinical dementia. Ever since the formulation of the ACH, however, there have been questions regarding whether it completely describes AD pathogenesis. This review critically examines various aspects of the ACH including its origin and development, the role of amyloid precursor protein (APP), whether SP and NFT are related to the development of clinical dementia, whether Aβ and tau are 'reactive' proteins, and whether there is a pathogenic relationship between SP and NFT. The results of transgenic experiments and treatments for AD designed on the basis of the ACH are also reviewed. It was concluded: (1) Aβ and tau could be the products rather than the cause of neuro-degeneration in AD, (2) it is doubtful whether there is a direct causal link between Aβ and tau, and (3) SP and NFT may not be directly related to the development of dementia, (4) transgenic models involving APP alone do not completely replicate AD pathology, and (5) treatments based on the ACH have been unsuccessful. Hence, a modification of the ACH is proposed which may provide a more complete explanation of the pathogenesis of AD.

On some Modifications of the Nekrassov Method for Numerical Solution of Linear Systems of Equations

A modification of the Nekrassov method for finding a solution of a linear system of algebraic equations is given and a numerical example is shown.

On the Approximation of the Generalized Cut Function of Degree p+1 By Smooth Sigmoid Functions

We introduce a modification of the familiar cut function by replacing the linear part in its definition by a polynomial of degree p + 1 obtaining thus a sigmoid function called generalized cut function of degree p + 1 (GCFP). We then study the uniform approximation of the (GCFP) by smooth sigmoid functions such as the logistic and the shifted logistic functions. The limiting case of the interval-valued Heaviside step function is also discussed which imposes the use of Hausdorff metric. Numerical examples are presented using CAS MATHEMATICA.

Clinical evaluation of the Shin-Nippon SRW-5000 autorefractor in adults:an update

Purpose: The Shin-Nippon SRW-5000 is an open view autorefractor that superseded the Canon R-1 autorefractor in the mid-1990s and has been used widely in optometry and vision science laboratories. It has been used to measure refractive error, accommodation responses both statically and dynamically, off-axis refractive error, and adapted to measure pupil size. This paper presents an overview of the original 2001 clinical evaluation of the SRW-5000 in adults (Mallen et al., Ophthal Physiol Opt 2001; 21: 101) and provides an update on the use and modification of the instrument since the original publication. Recent findings: The SRW-5000 instrument, and the family of devices which followed, have shown excellent validity, repeatability, and utility in clinical and research settings. The instruments have also shown great potential for increased research functionality following a number of modifications. Summary: The SRW-5000 and its derivatives have been, and continue to be, of significant importance in our drive to understand myopia progression, myopia control techniques, and oculomotor function in human vision.

Biodiversity of the surface microbial consortia from Limburger, Reblochon, Livarot, Tilsit, and Gubbeen cheeses

Comprehensive collaborative studies from our laboratories reveal the extensive biodiversity of the microflora of the surfaces of smear-ripened cheeses. Two thousand five hundred ninety-seven strains of bacteria and 2,446 strains of yeasts from the surface of the smear-ripened cheeses Limburger, Reblochon, Livarot, Tilsit, and Gubbeen, isolated at three or four times during ripening, were identified; 55 species of bacteria and 30 species of yeast were found. The microfloras of the five cheeses showed many similarities but also many differences and interbatch variation. Very few of the commercial smear microorganisms, deliberately inoculated onto the cheese surface, were reisolated and then mainly from the initial stages of ripening, implying that smear cheese production units must have an adventitious "house" flora. Limburger cheese had the simplest microflora, containing two yeasts, Debaryomyces hansenii and Geotrichum candidum, and two bacteria, Arthrobacter arilaitensis and Brevibacterium aurantiacum. The microflora of Livarot was the most complicated, comprising 10 yeasts and 38 bacteria, including many gram-negative organisms. Reblochon also had a very diverse microflora containing 8 yeasts and 13 bacteria (excluding gram-negative organisms which were not identified), while Gubbeen had 7 yeasts and 18 bacteria and Tilsit had 5 yeasts and 9 bacteria. D. hansenii was by far the dominant yeast, followed in order by G. candidum, Candida catenulata, and Kluyveromyces lactis. B. aurantiacum was the dominant bacterium and was found in every batch of the 5 cheeses. The next most common bacteria, in order, were Staphylococcus saprophyticus, A. arilaitensis, Corynebacterium casei, Corynebacterium variabile, and Microbacterium gubbeenense. S. saprophyticus was mainly found in Gubbeen, and A. arilaitensis was found in all cheeses but not in every batch. C. casei was found in most batches of Reblochon, Livarot, Tilsit, and Gubbeen. C. variabile was found in all batches of Gubbeen and Reblochon but in only one batch of Tilsit and in no batch of Limburger or Livarot. Other bacteria were isolated in low numbers from each of the cheeses, suggesting that each of the 5 cheeses has a unique microflora. In Gubbeen cheese, several different strains of the dominant bacteria were present, as determined by pulsed-field gel electrophoresis, and many of the less common bacteria were present as single clones. The culture-independent method, denaturing gradient gel electrophoresis, resulted in identification of several bacteria which were not found by the culture-dependent (isolation and rep-PCR identification) method. It was thus a useful complementary technique to identify other bacteria in the cheeses. The gross composition, the rate of increase in pH, and the indices of proteolysis were different in most of the cheeses.

Living on both sides of the fence: A phenomenological study of human resource development professionals as downsizing survivors and strategic human resource development facilitators

This phenomenological study explored how HR professionals who identified themselves as facilitators of strategic HRD (SHRD) perceived the experience of being an organizational agent-downsizing survivor. Criterion and snowball sampling were used to recruit 15 participants for this study. A semi-structured interview guide was used to interview participants. Creswell's (2007) simplified version of Moustakas's (1994) Modification of the Stevick-Colaizzi-Keen Method of Analysis of Phenomenological Data was used to analyze the data. Four main themes and corresponding sub-themes emerged from an inductive data analysis. The four main themes were a) the emotionality of downsizing, b) feeling responsible, c) choice and control, and d) possibilities for growth. Participants perceived downsizing as an emotional organizational change event that required them to manage their own emotions while helping others do the same. They performed their roles within an organizational atmosphere that was perceived as chaotic and filled with apprehension, shock, and a sense of ongoing loss, sadness and grieving. They sometimes experienced guilt and doubt and felt deceptive for having to keep secrets from others when planning for downsizing. Participants felt a strong sense of responsibility to protect employees emotionally, balance employee and organizational interests, and try to ensure the best outcomes for both. Often being there for others meant that they put on their games faces and took care of themselves last. Participants spoke of the importance of choosing one's attitude, being proactive rather than reactive, and finding ways to regain control in the midst of organizational crisis. They also perceived that although downsizing was emotionally difficult to go through that it provided possibilities for self, employee, and organizational growth.

Determination of Uranium, Thorium, and Ionium in sediment cores of the Caribbean and Ionian Sea

A rapid procedure for Io (Th230) dating of sediments with accumulation rates in the range of several cm/1000 years is described. Studying of large sample populations with very small Io-excess activity is possible as the counting time (around 1500 min/sample) are 2 to 5 times shorter than with the standard Io-excess method. Improved sensitivity of the Io-excess measurement is achieved by: 1) extraction ( ~90 %) of the authigenic Io-excess with EDTA, with minor leaching ( ~30 %) of the allogenic Th232 and Io-supported, 2) processing samples as large as 10 g or more. The procedure was applied to sediments from the Caribbean (V 12-122) and from the Ionian Sea (M22_48 and M17_17). In the case of the standard core V 12-122 our results are in good agreement with previous time-consuming Io determinations. The resulting average accumulation rates of 2.0 ± 0.3 cm/1000 years for the Ionian Sea cores are close to the average derived from magnetic reversal studies of a nearby core.