bluuebunny/crossref_metadata_2025_split huggingface dataset:
Advances in antimicrobial peptide immunobiology
Authors: Yount Nannette Y. , Bayer Arnold S. , Xiong Yan Q. , Yeaman Michael R. 
Published: May 2006

AbstractAntimicrobial peptides are ancient components of the innate immune system and have been isolated from organisms spanning the phylogenetic spectrum. Over an evolutionary time span, these peptides have retained potency, in the face of highly mutable target microorganisms. This fact suggests important coevolutionary influences in the host–pathogen relationship. Despite their diverse origins, the majority of antimicrobial peptides have common biophysical parameters that are likely essential for activity, including small size, cationicity, and amphipathicity. Although more than 900 different antimicrobial peptides have been characterized, most can be grouped as belonging to one of three structural classes: (1) linear, often of α‐helical propensity; (2) cysteine stabilized, most commonly conforming to β‐sheet structure; and (3) those with one or more predominant amino acid residues, but variable in structure. Interestingly, these biophysical and structural features are retained in ribosomally as well as nonribosomally synthesized peptides. Therefore, it appears that a relatively limited set of physicochemical features is required for antimicrobial peptide efficacy against a broad spectrum of microbial pathogens.During the past several years, a number of themes have emerged within the field of antimicrobial peptide immunobiology. One developing area expands upon known microbicidal mechanisms of antimicrobial peptides to include targets beyond the plasma membrane. Examples include antimicrobial peptide activity involving structures such as extracellular polysaccharide and cell wall components, as well as the identification of an increasing number of intracellular targets. Additional areas of interest include an expanding recognition of antimicrobial peptide multifunctionality, and the identification of large antimicrobial proteins, and antimicrobial peptide or protein fragments derived thereof. The following discussion highlights such recent developments in antimicrobial peptide immunobiology, with an emphasis on the biophysical aspects of host‐defense polypeptide action and mechanisms of microbial resistance. © 2006 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 84: 435–458, 2006This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Adsorption of albumin on prosthetic materials: Implication for tribological behavior
Authors: Serro A.P. , Gispert M.P. , Martins M.C.L. , Brogueira P. , Colaço R. , Saramago B. 
Published: May 2006

AbstractThe orthopedic prosthesis used to substitute damaged natural joints are lubricated by a pseudosynovial fluid that contains biological macromolecules with potential boundary lubrication properties. Proteins are some of those macromolecules whose role in the lubrication process is not yet completely understood. In a previous work, we investigated the influence of the presence of albumin, the major synovial protein, upon the tribological behavior of three of the most used pairs of artificial joint materials: ultra high molecular weight polyethylene (UHMWPE) against counterfaces of alumina, CoCrMo alloy, and 316L stainless steel. Albumin was found to cause a significant decrease in the friction coefficient when the counterfaces were metallic because transfer of UHMWPE was avoided, but this effect was much weaker in the case of alumina. The objective of the present work was to look for an explanation for these differences in tribological behavior in terms of albumin adsorption. With this goal, studies on adsorption of bovine serum albumin (BSA) on the counterface materials, from a biological model fluid (Hanks' balanced salt solution), were carried out using radiolabeled albumin (125I‐BSA), X‐ray photoelectron spectroscopy, and atomic force microscopy. The conclusion from all techniques is that the driving force for albumin adsorption is higher on the metals than on alumina. These results confirm that the greater the amount of protein adsorbed on the counterface, the more efficient is the protection against the transfer of polymeric film to the counterface. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Influence of different restorative materials on lysozyme and amylase activity of the salivary pellicle in situ
Authors: Hannig Christian , Wasser Mathias , Becker Klaus , Hannig Matthias , Huber Karin , Attin Thomas 
Published: May 2006

AbstractLysozyme and amylase are the most abundant enzymatic components in the salivary pellicle. The purpose of the present study was to determine the influence of different substrata on amylase and lysozyme activity in salivary pellicles formed in situ. Slabs (5 mm diameter) of bovine dentine and enamel, of titanium, gold alloy, resin composite, PMMA, amalgam, and feldspar ceramic were fixed on the buccal sites of individual splints worn by six subjects for 30 min to allow pellicle formation. Thereafter, slabs were removed from the trays and rinsed with running water. Lysozyme activity was determined via lysis of Micrococcus lysodeicticus. Amylase activity was measured with a photometric method using 2‐chloro‐4‐nitrophenyl‐4‐O‐β‐D‐galactopyranosylmaltotriosid (GalG2CNP) as substrate. Both pellicle enzymes were evaluated in the immobilized as well as in the desorbed state. Salivary enzyme activities were also measured. All investigated pellicles exhibited lysozyme and amylase activity. Great intraindividual and interindividual differences were observed. Over all samples, immobilized amylase activity amounted to 0.65 ± 0.64 mU/cm2. Immobilized lysozyme activity was 5.04 ± 1.55 U/cm2. There were no major effects of the substratum on pellicle‐bound amylase and lysozyme activity. Immobilized and desorbed enzyme activities revealed a strong correlation (lysozyme: r = 0.700; amylase: r = 0.990). Salivary enzyme activities had only little impact on pellicle‐bound enzyme activities. Amylase and lysozyme are incorporated in the acquired in situ pellicle on different solid surfaces in an active conformation. Dental material and enzyme activity in the saliva have only little impact on enzymatic activity in the pellicle in situ. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Non‐invasive detection of antibiotics and physiological substances in the aqueous humor by raman spectroscopy
Authors: Sideroudi Theoharia I. , Pharmakakis Nikolaos M. , Papatheodorou George N. , Voyiatzis George A. 
Published: May 2006

AbstractBackground and ObjectivesLaser Raman spectroscopy is an inelastic light scattering technique able to characterize molecules in aqueous environments. The purpose of this work is to develop a non‐contact and non‐invasive spectroscopic method to identify and eventually quantify the presence of medicines (e.g., antibiotics) and physiological substances (e.g., glucose) in the aqueous humor of the eye.Study Design/Materials and MethodsA new laser light delivery probe has been developed and adapted to a Raman spectroscopic system with the ability of favorable collection of the Raman light at 90° scattering geometry while scanning the anterior chamber of the eye. Different amounts of ceftazidime, amphotericin B, and glucose had been injected in the aqueous humor of porcine eyes, maximum 24 hours after death and extraction, in‐vitro. Raman measurements were excited with a visible (514.5 nm) laser beam at a power of 25 mW and an exposure/acquisition time of 1 second.ResultsThe specific collection optics and Raman analysis components used in the present work have resolved the Raman signatures of probed molecules and low concentrations of ceftazidime (0.9 mg/mL), amphotericin B (9 µg/mL), and glucose (2 mg/ml) separately injected in the anterior chamber of porcine eyes were detected in vitro.ConclusionThis special illumination design gives the opportunity of avoiding the direct exposure to the laser light of basic cordial tissues of the eye, like lens and retina, although an optimum collection of scattered light is accomplished. Concentrations close to the minimum inhibitory concentration (MIC) have been detected for ceftazidime and amphotericin b; the detection of glucose has been realized at concentrations close to the early pathological levels of patients with diabetes. Lasers Surg. Med. © 2006 Wiley‐Liss, Inc.
EGFR amplification and lack of activating mutations in metaplastic breast carcinomas
Authors: Reis‐Filho JS , Pinheiro C , Lambros MBK , Milanezi F , Carvalho S , Savage K , Simpson PT , Jones C , Swift S , Mackay A , Reis RM , Hornick JL , Pereira EM , Baltazar F , Fletcher CDM , Ashworth A , Lakhani SR , Schmitt FC 
Published: May 2006

AbstractMetaplastic breast carcinomas are reported to harbour epidermal growth factor receptor (EGFR) overexpression in up to 80% of the cases, but EGFR gene amplification is the underlying genetic mechanism in around one‐third of these. In this study, EGFR gene amplification as defined by chromogenic in situ hybridization and protein overexpression was examined in a cohort of 47 metaplastic breast carcinomas. Furthermore, the presence of activating EGFR mutations in exons 18, 19, 20, and 21 was investigated. Thirty‐two cases showed EGFR overexpression and of these, 11 (34%) harboured EGFR gene amplification. In addition, EGFR amplification showed a statistically significant association with EGFR overexpression (p < 0.0094) and was restricted to carcinomas with homologous metaplasia. Ten cases, five with and five without EGFR amplification, were subjected to microarray‐based CGH, which demonstrated that EGFR copy number gain may occur by amplification of a discrete genomic region or by gains of the short arm of chromosome 7 with a breakpoint near the EGFR gene locus, the minimal region of amplification mapping to EGFR, LANCL2, and SEC61G. No activating EGFR mutations were identified, suggesting that this is unlikely to be a common alternative underlying genetic mechanism for EGFR expression in metaplastic breast carcinomas. Given that metaplastic breast carcinomas are resistant to conventional chemotherapy or hormone therapy regimens and that tumours with EGFR amplification are reported to be sensitive to EGFR tyrosine kinase inhibitors, these findings indicate that further studies are warranted to explore EGFR tyrosine kinase inhibitors as potential therapeutic agents for metaplastic breast carcinomas harbouring amplification of 7p11.2. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Proteomic analysis of tomato fruits from two ecotypes during ripening
Authors: Rocco Mariapina , D'Ambrosio Chiara , Arena Simona , Faurobert Mirelle , Scaloni Andrea , Marra Mauro 
Published: May 2006

AbstractRipening of climacteric fruits is a complex physiological phenomenon, which makes berries attractive/palatable and also determines their nutritional characteristics. We report here a comparative proteomic investigation on tomato fruits from a regional and commercial elite ecotype during maturation. Several hundreds of protein components were resolved on 2‐DE gels (pH range 4–7) stained with colloidal Coomassie; almost 57% presented overlapping gel coordinates between the two compared varieties. Specific proteins were recognized in each ecotype as differentially expressed during ripening. Constant and variable components were excised, in‐gel digested and analysed by MALDI‐TOF‐MS and µLC‐ESI‐IT‐MS/MS approaches. Peptide MS and MS/MS data were searched against publicly available protein and EST databases, and 83 protein spots were unambiguously identified by MS. Gel matching procedures allowed further identification of proteins between ecotypes. In general, common variably expressed proteins in both ecotypes during maturation were associated to important physiological processes such as redox status control, defence, stress, carbon metabolism, energy production and cellular signalling. Protein components differentially expressed in each variety were also identified. The role of some of the identified proteins in the berries is discussed in relation to tomato fruit ripening. Accordingly, this investigation provides the first characterization of the tomato fruit proteome and description of its variation during maturation.
SPECTRAL EVIDENCE FOR A NEW PHOTOREACTIVE COMPONENT OF THE OXYGEN-EVOLVING SYSTEM IN PHOTOSYNTHESIS
Authors: Knaff David B. , Arnon Daniel I. 
Published: May 2006

On illuminating chloroplasts with “short-wavelength” monochromatic light that supports oxygen evolution, spectral evidence was obtained for a new photoreactive chloroplast component, provisionally designated C550, which shows a reversible decrease of absorbance with a maximum at 550 mμ. The light-induced absorbance changes in C550 have been separated from those due to cytochromes in the same spectral region.
The light-induced decrease of absorbance in C550 appears to be independent of temperature, persisting even at -189° and is therefore likely to be linked to the primary light reaction associated with oxygen evolution in photosynthesis.
Isolation of a 5S RNA-Protein Complex from Mammalian Ribosomes
Authors: Blobel Günter 
Published: May 2006

5S RNA is removed from the large ribosomal subunit of both rat liver and rabbit reticulocyte ribosomes by treatment with EDTA to remove magnesium ions. The RNA is removed not as a naked molecule, but in association with a single ribosomal protein (molecular weight about 35,000) as a ribonucleoprotein, sedimenting at about 7 S. Conditions for the exclusive removal of the 5S RNA-protein complex have been established.
Both ribosomal subunits undergo distinct changes in their sedimentation rate, concomitant with the loss of their biological activity, when sedimented into sucrose gradients containing high concentrations of monovalent ions and low concentrations of magnesium. Under these conditions the large subunit loses 5S RNA, the 5S RNA-associated protein, and several more proteins.
Reducible Crosslinks in Hydroxylysine-Deficient Collagens of a Heritable Disorder of Connective Tissue
Authors: Eyre David R. , Glimcher Melvin J. 
Published: May 2006

Reducible compounds that participate in crosslinking were analyzed in hydroxylysine-deficient collagens of patients with a heritable disorder of connective tissue. After treatment with [
3
H]sodium borohydride, new compounds, as well as a totally different pattern of tritiated compounds, were found in hydroxylysine-deficient collagen from skin as compared with age-matched controls. The amount of desmosines detected indicated that more elastin was present in abnormal skin than in control skin.

Bone collagen, which was not as deficient in hydroxylysine as skin collagen, had the same compounds as normal bone collagen, but their relative proportions were altered, consistent with a deficiency of hydroxylysine, a precursor of the crosslinks. Although the content of hydroxylysine in collagen of cartilage is essentially normal in these patients, analysis after reduction revealed a different pattern of reduced compounds from that of normal cartilage. It is speculated that Type II collagen, the major collagen component in cartilage, contains a normal amount of hydroxylysine, while Type I collagen, which is the major source of the crosslinks, is hydroxylysine-deficient. This distribution would explain the findings of an abnormal profile of reducible compounds despite an almost normal total hydroxylysine content.
The finding that the deficiency of hydroxylysine in the collagen of these patients is accompanied by changes in number, chemical nature, and, probably, distribution of crosslinkages, and the previously reported alterations in the solubility characteristics, suggest that at least some skeletal and connective tissue abnormalities are directly related to underlying molecular pathology.
Carotenoid Transformations in the Chloroplast Envelope
Authors: Jeffrey S. W. , Douce Roland , Benson A. A. 
Published: May 2006

The envelope of the spinach chloroplast is a yellow membrane system with a unique carotenoid composition. Envelopes prepared from dark-treated leaves had a violaxanthin content up to 3.5 times the lutein plus zeaxanthin content, whereas in chloroplast envelopes from illuminated leaves this ratio was only 0.75. Light-catalyzed changes in violaxanthin content also occurred in the thylakoid fraction.
The role of this reversible light-catalyzed de-epoxidation of violaxanthin in the function of the envelope of the chloroplast is discussed.
Constancy in Human Sperm DNA Content
Authors: Sarkar Siddhartha , Jones O. W. , Shioura Norio 
Published: May 2006

The frequency distribution of DNA content of human sperm was measured in an automated flow microfluorometer. The flow method measures the DNA content by quantifying the amount of fluorescence emitted by the fluorescent Feulgen stained DNA of single sperm cells suspended in microdroplets. The variability in the mean value for the haploid amount of DNA in sperm from 15 randomly chosen donors was less than 1%. Statistical tests on the observed frequency distribution data indicated that each sperm population probably consists of two homogenous components present in almost equal proportions but differing in mean DNA content. The difference in their modal values for DNA is within the range of known values of DNA difference between the two sex chromosomes.
Sperm of donors segregating balanced translocations, when compared to the random samples as a class, showed greater variability in the mean DNA content.
MAGNIFYING COLONOSCOPY FOR THE DIAGNOSIS OF INFLAMMATORY CHANGES IN ULCERATIVE COLITIS
Authors: Sugano Satoshi , Fujinuma Sumio , Sakai Yoshihiro 
Published: May 2006

Background:  Endoscopic observation is the most effective method for the evaluation of staging in ulcerative colitis (UC). However, in cases with very mild inflammatory activity, histopathological diagnosis may also be required. Unfortunately, biopsy‐related accidents are not uncommon. As an alternative, we have used a magnifying colonoscope commonly used for tumor diagnosis to examine in detail the colon mucosa of UC patients in clinical remission, and then compared these findings relative to conventional endoscopy using histopathological diagnosis.Subjects and Methods:  Among UC cases examined by colonoscopy between April 2000 and April 2005, 27 cases without hematochezia for at least 1 month were enrolled in this study. Following observations of inflammatory changes using conventional colonoscopy, magnifying observation and biopsies at a total of 144 sites were evaluated. Using histopathological standards, acute‐phase inflammation was indicated by the presence of neutrophil infiltration, whereas chronic‐phase inflammation was indicated by infiltration of lymphocytes, plasma cells and eosinophils.Results:  Indicators of significant inflammation by conventional observation was erosion. Under magnification, inflammation appears as superficial defects in mucosa and small whitish spots. When the presence of infiltrating neutrophils was used as a positive histological marker for inflammation, there was no difference in the accuracy of diagnosis by conventional observation (95.1%) versus magnifying observation (97.2%). In contrast, when lymphocyte infiltration was used as a marker, the accuracy of diagnosis increased significantly (88.2%) using magnifying observation relative to conventional observation (61.1%).Conclusions:  Magnifying endoscopy can be used effectively in the evaluation of minute mucosal changes in cases of UC remission.
Role of MAP Kinase‐Dependent Apoptotic Pathway in Innate Immune Responses and Viral Infection
Authors: Sumbayev V. V. , Yasinska I. M. 
Published: May 2006

AbstractMitogen‐activated protein (MAP) kinase cascades are multifunctional signalling networks that influence cell growth, differentiation, apoptosis and cellular responses to stress. Apoptosis signal‐regulating kinase 1 (ASK1) is a MAP kinase kinase kinase that triggers apoptogenic kinase cascade leading to the phosphorylation/activation of c‐Jun N‐terminal kinases (JNK) and p38‐MAP kinase, which are responsible to induce apoptotic cell death. This pathway plays a pivotal role in the transduction of signals from different apoptotic stimuli. Recently, it has become evident that ASK1 and its downstream pathway are employed in the transduction of signals from Toll‐like receptors (TLR) – multistep processes that interfere with different intracellular signalling pathways. TLR are the key proteins that allow mammals to detect pathogens and mediate innate immune responses. In addition, ASK1 and its downstream pathway play a target role in the regulation of apoptosis in some cases of viral infection – AIDS, influenza, hepatitis C and others. In the present review, we summarize current knowledge about the role of ASK1 and its downstream pathway in innate immune responses and viral infection.
On the track of the Red Queen: bark beetles, their nematodes, local climate and geographic parthenogenesis
Authors: Meirmans S. , Skorping A. , Løyning M. K. , Kirkendall L. R. 
Published: May 2006

Abstract
Geographic parthenogenesis has been explained as resulting from parasite pressure (Red Queen hypothesis): several studies have found high degrees of sexuals where the prevalence of parasites is high. However, it is important to address whether prevalence of parasites mirrors risk of infection. We explored geographic parthenogenesis of Ips acuminatus bark beetles and their nematodes. Local climate is crucial for nematode stages outside the host, in spring and summer, and prevalence should thus be associated with those temperatures if prevalence reliably reflects exposure risk across populations. This was the case; however, high prevalence of a virulent nematode species was not associated with many sexuals, whereas highly sexual populations were characterized by high infection risk of benign nematodes. Low virulence of the latter makes Red Queen dynamics unlikely. Geographical patterns of parthenogenesis were instead associated with winter temperature and variance in temperature.