bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure-Function Relationships in the HAMP and Proximal Signaling Domains of the Aerotaxis Receptor Aer
Authors: Watts Kylie J. , Johnson Mark S. , Taylor Barry L. 
Published: January 2008

ABSTRACT

Aer, the
Escherichia coli
aerotaxis receptor, faces the cytoplasm, where the PAS (
P
er-
A
RNT-
S
im)-flavin adenine dinucleotide (FAD) domain senses redox changes in the electron transport system or cytoplasm. PAS-FAD interacts with a HAMP (
h
istidine kinase,
a
denylyl cyclase,
m
ethyl-accepting protein, and
p
hosphatase) domain to form an input-output module for Aer signaling. In this study, the structure of the Aer HAMP and proximal signaling domains was probed to elucidate structure-function relationships important for signaling. Aer residues 210 to 290 were individually replaced with cysteine and then cross-linked in vivo. The results confirmed that the Aer HAMP domain is composed of two α-helices separated by a structured loop. The proximal signaling domain consisted of two α-helices separated by a short undetermined structure. The Af1503 HAMP domain from
Archaeoglobus fulgidus
was recently shown to be a four-helix bundle. To test whether the Af1503 HAMP domain is a prototype for the Aer HAMP domain, the latter was modeled using coordinates from Af1503. Several findings supported the hypothesis that Aer has a four-helix HAMP structure: (i) cross-linking independently identified the same residues at the dimer interface that were predicted by the model, (ii) the rate of cross-linking for residue pairs was inversely proportional to the β-carbon distances measured on the model, and (iii) clockwise lesions that were not contiguous in the linear Aer sequence were clustered in one region in the folded HAMP model, defining a potential site of PAS-HAMP interaction during signaling. In silico modeling of mutant Aer proteins indicated that the four-helix HAMP structure was important for Aer stability or maturation. The significance of the HAMP and proximal signaling domain structure for signal transduction is discussed.
High-intensity ultraendurance promotes early release of muscle injury markers
Authors: Bessa A , Nissenbaum M , Monteiro A , Gandra P G , Nunes L S , Bassini-Cameron A , Werneck-de-Castro J P S , de Macedo D Vaz , Cameron L-C 
Published: January 2008

Objective:To evaluate the impact of high-intensity ultraendurance (HIU) cycling, using it as a possible way to understand muscle injury kinetics and blood immune cells’ release during high-intensity prolonged exerciseDesign:Male amateur triathletes enrolled during a cycling race of the International Bike Championship 800 km cycling relay (∼23 h). Each athlete alternately cycled 20–25 minutes until exhaustion and performed a total of approximately 200 km.Results:Creatine kinase levels in blood reached a 300% rise in a sigmoidal pattern, while lactate dehydrogenase levels increased by 30–40% following a hyperbolic pattern. Aspartate aminotransferase and alanine aminotransferase levels increased by up to 250% and 140%, respectively. Liver injury markers such as alkaline phosphatase and γ-glutamyltransferase remained stable. Platelets increased by 20–30% from pre-exercise, and there was no change in haematocrit during the race. White blood cells rose by nearly 200%. Leucocytes rose 210% during the race, with a major component coming from neutrophils, which increased more than 300%. Triacylglycerol levels were decreased at the finish and total cholesterol levels remained unchanged. Urate increased (by up to 35%) during the first half of the race, and urea levels increased with a different pattern, increasing by 45% in the second half.Conclusions:This study showed the blood appearance kinetics of muscle injury markers and some metabolites. It is suggested that the increase in these enzymes came primarily from muscle damage, rather than liver damage, and that white blood cells are selectively mobilised independently of haemoconcentration. The early appearance of muscle injury markers in this kind of exercise was also shown.
Is the association between job strain and carotid intima-media thickness attributable to pre-employment environmental and dispositional factors? The Cardiovascular Risk in Young Finns Study
Authors: Hintsa T , Kivimäki M , Elovainio M , Vahtera J , Hintsanen M , Viikari J S A , Raitakari O T , Keltikangas-Järvinen L 
Published: January 2008

Objectives:Most previous studies of job strain and cardiovascular risk have been limited to adult data. It remains unclear whether this association might be explained by factors already present before entering the labour market. This study examined whether pre-employment family factors and participants’ own dispositional factors contribute to the relationship between job strain and carotid intima-media thickness (CIMT) among male employees.Methods:The sample consisted of 494 men from the Cardiovascular Risk in Young Finns Study. Parental socioeconomic position and parental life dissatisfaction were assessed at 9–21 years of age and components of type A behaviour (Hunter-Wolf) were assessed at 12–24 years of age before the participants had entered the labour market. Job strain, education and CIMT were assessed at 27–39 years of age when all participants were employed.Results:There was an association between higher job strain and increased CIMT in adulthood (mean 0.59 mm; 95% CI 0.42 to 0.76) which was only slightly affected on adjustment for parental socioeconomic position and parental life dissatisfaction as well as participants’ education. However, the job strain/CIMT relationship attenuated by 17% to non-significant after taking into account the effect of the participants’ type A behaviour components.Conclusions:In this contemporary cohort of men, lack of leadership (a type A behaviour component) contributed to the association between job strain and CIMT 15 years later, whereas pre-employment family factors had only a modest effect on this association.
Role of comorbidities in a cohort of patients with COPD undergoing pulmonary rehabilitation
Authors: Crisafulli E , Costi S , Luppi F , Cirelli G , Cilione C , Coletti O , Fabbri L M , Clini E M 
Published: January 2008

Background:Chronic obstructive pulmonary disease (COPD) is often associated with other chronic diseases. These patients are often admitted to hospital based rehabilitation programmes.Objectives:To determine the prevalence of chronic comorbidities in patients with COPD undergoing pulmonary rehabilitation and to assess their influence on outcome.Design:Observational retrospective cohort study.Setting:A single rehabilitation centre.Patients:2962 inpatients and outpatients with COPD (73% male, aged 71 (SD 8) years, forced expiratory volume in 1 s (FEV1) 49.3 (SD 14.8)% of predicted), graded 0, 1 or ⩾2 according to the comorbidity categories and included in a pulmonary rehabilitation programme.Measurements:The authors analysed the number of self-reported comorbidities and recorded the Charlson Index. They then calculated the percentage of patients with a predefined positive response to pulmonary rehabilitation (minimum clinically important difference (MCID)), as measured by improvement in exercise tolerance (6 min walking distance test (6MWD)), dyspnoea (Medical Research Council scale) and/or health related quality of life (St George’s Respiratory Questionnaire (SGRQ)).Results:51% of the patients reported at least one chronic comorbidity added to COPD. Metabolic (systemic hypertension, diabetes and/or dyslipidaemia) and heart diseases (chronic heart failure and/or coronary heart disease) were the most frequently reported comorbid combinations (61% and 24%, respectively) among the overall diseases associated with COPD. The prevalence of patients with MCID was different across the comorbidity categories and outcomes. In a multiple categorical logistic regression model, the Charlson Index (OR 0.72 (96% CI 0.54 to 0.98) and 0.51 (96% CI 0.38 to 0.68) vs 6MWD and SGRQ, respectively), metabolic diseases (OR 0.57 (96% CI 0.49 to 0.67) vs 6MWD) and heart diseases (OR 0.67 (96% CI 0.55 to 0.83) vs SGRQ) reduced the probability to improve outcomes of rehabilitation.Conclusions:Most patients with COPD undergoing pulmonary rehabilitation have one or more comorbidities. Despite the fact that the presence of comorbidities does not preclude access to rehabilitation, the improvement in exercise tolerance and quality of life after rehabilitation may be reduced depending on the comorbidity.
Novel Blood-Based, Five-Gene Biomarker Set for the Detection of Colorectal Cancer
Authors: Han Mark , Liew Choong Tsek , Zhang Hong Wei , Chao Samuel , Zheng Run , Yip Kok Thye , Song Zhen-Ya , Li Hiu Ming , Geng Xiao Ping , Zhu Li Xin , Lin Jian-Jiang , Marshall K. Wayne , Liew Choong Chin 
Published: January 2008

AbstractPurpose: We applied a unique method to identify genes expressed in whole blood that can serve as biomarkers to detect colorectal cancer (CRC).Experimental Design: Total RNA was isolated from 211 blood samples (110 non-CRC, 101 CRC). Microarray and quantitative real-time PCR were used for biomarker screening and validation, respectively.Results: From a set of 31 RNA samples (16 CRC, 15 controls), we selected 37 genes from analyzed microarray data that differed significantly between CRC samples and controls (P &lt; 0.05). We tested these genes with a second set of 115 samples (58 CRC, 57 controls) using quantitative real-time PCR, validating 17 genes as differentially expressed. Five of these genes were selected for logistic regression analysis, of which two were the most up-regulated (CDA and MGC20553) and three were the most down-regulated (BANK1, BCNP1, and MS4A1) in CRC patients. Logit (P) of the five-gene panel had an area under the curve of 0.88 (95% confidence interval, 0.81-0.94). At a cutoff of logit (P) &gt;+0.5 as disease (high risk), &lt;−0.5 as control (low risk), and in between as an intermediate zone, the five-gene biomarker combination yielded a sensitivity of 94% (47 of 50) and a specificity of 77% (33 of 43). The intermediate zone contained 22 samples. We validated the predictive power of these five genes with a novel third set of 92 samples, correctly identifying 88% (30 of 34) of CRC samples and 64% (27 of 42) of non-CRC samples. The intermediate zone contained 16 samples.Conclusion: Our results indicate that the five-gene biomarker panel can be used as a novel blood-based test for CRC.
Who is sitting next to me? Relatedness between next neighbours in common lizards
Authors: Hofmann Sylvia 
Published: January 2008

AbstractSeveral lizard species have been shown to exhibit kin recognition, including green iguanas (Iguana iguana), three Australian Scincid species (Egernia stokesii, E. striolata and Tiliqua rugosa) and common lizards (Lacerta vivipara). Thus, observations of close neighboured individuals of the common lizard that consist of differently or same-aged individuals at a given site may generate speculation about the relatedness structure of such combinations and putative “social” patterns of this species. A total of 682 lizards were sampled from a population in a nature reserve near Leipzig, Germany. Relatedness statistics were calculated using five microsatellite DNA loci. The relatedness of individuals that were sighted or captured together was compared by grouping them on sex and age. The results showed that pairs of adults and juveniles were significantly more related than all other combinations, with adults showing the lowest mean values of relatedness, followed by a similar low level of relatedness between subadults. Most “pairs” were found in juveniles. Pairs of subadults and juveniles as well as of adults and juveniles consisted mainly of females. In subadults and adults, males were non-related. Little evidence was found to indicate that relatedness is relevant to the spatial distance between individuals. The relatedness patterns of associated individuals may arise from male sex-biased dispersal rather than from active kin preferences based on kin discrimination.
Is melanism adaptive in sea kraits?
Authors: Bonnet Xavier , Lorioux Sophie , Brischoux François , De Crignis Margot 
Published: January 2008

AbstractOntogenic melanism (progressive darkening of the skin) has been documented in snakes. Black coloration of the skin often compromises the cryptic effects associated with other patterns (e.g. zigzags) and exposes individuals to predation; however, the mortality risk can be balanced, for example by a thermoregulatory advantage during sun basking. Such adaptive context has been proposed to explain the appearance and the maintenance of melanism within snake populations. Based on a very large captures and re-captures sample (>8000 observations) gathered on two species of sea-kraits (Laticauda saintgironsi and L. laticaudata in New Caledonia), we observed that melanism occurred in only one species (L. laticaudata), was infrequent and concerned adult snakes solely. None of three adaptive hypotheses respectively linked to thermoregulation, predation, or protection against sun radiations, provided a satisfactory account for the occurrence of melanism in our study populations. Therefore, we suggest that melanism was a fortuitous phenomenon.
Estimating altitude in distribution records of Amphibians and Reptiles: a comparative study between topographic maps and Remote Sensing data
Authors: García-Meléndez Eduardo , Ribeiro Raquel , Brito José Carlos , Sillero Neftalí 
Published: January 2008

AbstractAltitude is an important factor when explaining species distributions. However, many biogeographical studies register altitude directly through topographic maps; a time-consuming manual process prone to mistakes. Currently, GIS and DEMs allow this work to be done more efficiently. Two methods for registering altitude for locations of amphibians and reptiles in the Iberian Peninsula were compared in order to evaluate their efficiency and similarity: manually through topographic maps, and automatically with a GIS, where two DEMs were analysed: the SRTM DEM and a DEM generated through topographic maps. The SRTM altitudes were similar to those recorded by the manual method (only Rana perezi presented differences), whereas the other DEM had differences in almost all amphibians and three reptiles. The differences between both DEMs corresponded mostly to rivers and band effect of radar sensor. The GIS method was faster, efficient and no time was consumed in searching and correcting human errors.
Phalangeal formulae and ontogenetic variation of carpal morphology in Testudo horsfieldii and T. hermanni
Authors: Hitschfeld Ellen , Auer Markus , Fritz Uwe 
Published: January 2008

AbstractWe compared variation in phalangeal and carpal morphology of the Central Asian Testudo horsfieldii, a burrow-digging tortoise species, with its sister taxon T. hermanni, a Mediterranean species without extensive digging behaviour. Thirty-two Testudo horsfieldii kazachstanica shared the same phalangeal formula (0-2-2-1-1). The distal carpal 1 and metacarpal I as well as the pisiform were consistently lacking, sometimes also the medial centrale. Phalangeal morphology was more variable in Testudo hermanni hermanni. In 29 specimens four phalangeal formulae were found that differed with respect to the reduction of digit 1 (1-2-2-2-1, M-2-2-2-1, D-2-2-2-1, 0-2-2-2-1). The pisiform develops late in ontogeny and is lacking in very most juveniles and subadults. In contrast to T. h. kazachstanica, the medial centrale is always present. In both T. h. kazachstanica and T. h. hermanni carpalia increasingly fuse with age and size. The underlying morphological patterns differ however. The extreme character state in aged T. h. kazachstanica is one large solid bone element, formed by the fused intermedium, ulnare and both centralia. Aged T. h. hermanni have, in contrast, two separate larger carpal elements, one formed by the fused lateral and medial centralia and the other by the fused distal carpalia 1 and 2; the intermedium and ulnare never fuse with one another or with other carpalia. While a partial or complete loss of digit 1 seems to be characteristic for all Testudo species, we propose that the extensive fusion of carpal elements in T. horsfieldii is correlated with its natural history because a rigid manus could be advantageous for burrow-digging. Also the reduction of digit 4 (one phalanx present), a rare character among testudinids and not occurring in other Testudo species, could be linked with its mode of life.
Population density in Podarcis lilfordi (Squamata, Lacertidae), a lizard species endemic to small islets in the Balearic Islands (Spain)
Authors: Pérez-Mellado Valentín , Martín-Vallejo Javier , Brown Richard , Picornell Antonia , Castro José , Ramón María Misericordia , Terrassa Bárbara , García-Díez Teresa , Hernández-Estévez José Ángel 
Published: January 2008

AbstractThe Balearic lizard, Podarcis lilfordi, is present in 43 insular populations in the Cabrera archipelago and around the coasts of Mallorca and Menorca islands (Spain). We studied lizard densities over the entire range of distribution, analyzing observed differences of density in relation to island area, habitat diversity, availability of resources, presence of predators, competitors and human disturbances. The density of the Balearic lizard varies from less than 35 to almost 8000 lizards ha–1, with an average of around 1500 lizards ha–1. In some very small islets we detected no more than 10 individuals. Using a subsample of nine coastal islets (Menorca) we did not find any significant correlation between ground arthropod biomass and lizard density. The combination of island area and its maximal altitude, its so-called biotic capacity, was also uncorrelated with lizard density. In addition, neither degree of island accessibility nor presence/absence of seagull breeding colonies, were able to explain lizard densities. Islands without ship rats (Rattus rattus) showed a significantly higher lizard density, but islands in which rat eradication programs were launched during the study period, showed lower densities than those with rats but no eradication actions. Genetic variability was significantly higher on bigger lizard populations, lacking a correlation with lizard densities. No single independent variable can explain density differences among populations under study. Our results are discussed in the light of available hypotheses on factors affecting population densities.
Phagocytosis and intracellular killing of MD-2 opsonized Gram-negative bacteria depend on TLR4 signaling
Authors: Jain Vishal , Halle Annett , Halmen Kristen A. , Lien Egil , Charrel-Dennis Marie , Ram Sanjay , Golenbock Douglas T. , Visintin Alberto 
Published: January 2008

AbstractBoth Toll-like receptor 4 (TLR4)– and MD-2–deficient mice succumb to otherwise nonfatal Gram-negative bacteria inocula, demonstrating the pivotal role played by these proteins in antibacterial defense in mammals. MD-2 is a soluble endogenous ligand for TLR4 and a receptor for lipopolysaccharide (LPS). LPS-bound MD-2 transmits an activating signal onto TLR4. In this report, we show that both recombinant and endogenous soluble MD-2 bind tightly to the surface of live Gram-negative bacteria. As a consequence, MD-2 enhances cellular activation, bacterial internalization, and intracellular killing, all in a TLR4-dependent manner. The enhanced internalization of MD-2–coated bacteria was not observed in macrophages expressing Lpsd, a signaling-incompetent mutant form of TLR4, suggesting that the enhanced phagocytosis observed is dependent on signal transduction. The data confirm the notion that soluble MD-2 is a genuine opsonin that enhances proinflammatory opsonophagocytosis by bridging live Gram-negative bacteria to the LPS transducing complex. The presented results extend our understanding of the role of the TLR4/MD-2 signaling axis in bacterial recognition by phagocytes.
Acute severe mitral regurgitation: consideration of papillary muscle architecture
Authors: Czarnecki Andrew , Thakrar Amar , Fang Tielan , Lytwyn Matthew , Ahmadie Roien , Pascoe Edward , Jassal Davinder S 
Published: January 2008

Abstract
We present a case of an individual who presented with acute severe mitral regurgitation in the setting of an inferior ST elevation myocardial infarction. Both transthoracic and transesophageal echocardiography demonstrated a posteriorly directed eccentric jet of severe mitral regurgitation with flail anterior mitral valve leaflet attached presumably to the anterior papillary muscle. Intraoperative findings demonstrated rupture of the postero-medial papillary muscle attached via chords to the anterior mitral valve leaflet. This case serves to remind us that both the anterior and posterior leaflets of the mitral valve are attached to both papillary muscle heads. The direction and eccentricity of the mitral regurgitant jet on echocardiography helps to locate the leaflet involved, but not necessarily the coexisting papillary muscle pathology.
Synchronous multiple small bowel intussusceptions in an adult with blue rubber bleb naevus syndrome: Report of a case and review of literature
Authors: Lee Clement , Debnath Debasish , Whitburn Tara , Farrugia Mark , Gonzalez Federico 
Published: January 2008

Abstract

Background
Blue rubber bleb naevus syndrome (BRBNS), is an uncommon condition characterised by cavernous haemangiomas of skin and gastrointestinal tract. The most common complication of this syndrome is gastrointestinal bleeding. Intussusception of bowel, although a known complication, has rarely been reported.

Case presentation
We report the case of a 37-year-old man who presented with multiple intussusceptions of small bowel. He required an urgent laparotomy and bowel resections. He suffered from BRBNS. This is the first reported case of multiple synchronous intussusceptions affecting both jejunum and ileum, secondary to haemangiomas occurring in an adult with BRBNS. The underlying conditions of acute abdomen in patients with BRBNS may include intramural haemorrhage, infarction, volvulus or intussusception of bowel. Treatment options include pharmacological manipulation, bowel resection, and interventions such as sclerotherapy, angiographic embolisation, endoscopic ligation, electrocautery and laser photocoagulation for visceral lesions.

Conclusion
A high index of suspicion is required whilst dealing with acute abdomen in patients with BRBNS. Clinical trials may provide some answers as to the preference of treatment in individual cases, as the current level of evidence does not offer a clear choice of optimal treatment.