bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of APOE Status on Lexical–Semantic Skills in Mild Cognitive Impairment
Authors: Biundo Roberta , Gardini Simona , Caffarra Paolo , Concari Letizia , Martorana Davide , Neri Tauro Maria , Shanks Michael F. , Venneri Annalena 
Published: March 2011

AbstractThis study characterized the relationship between apolipoprotein E (APOE) status and residual semantic abilities in amnestic mild cognitive impairment (MCI). APOE status (ε4 carrier/non ε4 carrier) was determined in 30 amnestic MCIs and in 22 healthy matched non ε4 carrier controls. The lexical characteristics (age of acquisition, typicality, familiarity) of words produced in a category fluency task were determined. MCIs produced fewer words than controls and these were also earlier acquired and more familiar. The words produced by MCI ε4 carriers were earlier acquired than those of non ε4 carriers. Analyses limited to the first 10 words produced by patients and controls showed similar findings and also revealed that MCI subgroups retrieved first more typical words than controls. Follow up showed higher conversion to Alzheimer's disease (AD) in MCI ε4 carriers than in non ε4 carriers. These findings show that a significant proportion of phenotype variability in performance on category fluency in people at increased AD risk is influenced by genetic factors. These findings explain why category fluency deficits, together with episodic memory deficits, are the only consistent early deficits in MCI patients who convert to AD. (JINS, 2011, 17, 423–430)
The crystal structure of the cephalosporin deacetylating enzyme acetyl xylan esterase bound to paraoxon explains the low sensitivity of this serine hydrolase to organophosphate inactivation
Authors: Montoro-García Silvia , Gil-Ortiz Fernando , García-Carmona Francisco , Polo Luis Mariano , Rubio Vicente , Sánchez-Ferrer Álvaro 
Published: March 2011

Organophosphorus insecticides and nerve agents irreversibly inhibit serine hydrolase superfamily enzymes. One enzyme of this superfamily, the industrially important (for β-lactam antibiotic synthesis) AXE/CAH (acetyl xylan esterase/cephalosporin acetyl hydrolase) from the biotechnologically valuable organism Bacillus pumilus, exhibits low sensitivity to the organophosphate paraoxon (diethyl-p-nitrophenyl phosphate, also called paraoxon-ethyl), reflected in a high Ki for it (~5 mM) and in a slow formation (t½~1 min) of the covalent adduct of the enzyme and for DEP (E-DEP, enzyme–diethyl phosphate, i.e. enzyme–paraoxon). The crystal structure of the E-DEP complex determined at 2.7 Å resolution (1 Å=0.1 nm) reveals strain in the active Ser181-bound organophosphate as a likely cause for the limited paraoxon sensitivity. The strain results from active-site-size limitation imposed by bulky conserved aromatic residues that may exclude as substrates esters having acyl groups larger than acetate. Interestingly, in the doughnut-like homohexamer of the enzyme, the six active sites are confined within a central chamber formed between two 60°-staggered trimers. The exclusive access to this chamber through a hole around the three-fold axis possibly limits the size of the xylan natural substrates. The enzyme provides a rigid scaffold for catalysis, as reflected in the lack of movement associated with paraoxon adduct formation, as revealed by comparing this adduct structure with that also determined in the present study at 1.9 Å resolution for the paraoxon-free enzyme.
Thiols stabilize cobblestone morphology of cultured mesothelial cells
Authors: Bird Stephen D , Legge Michael , Walker Robert J. 
Published: March 2011

AbstractCellular thiols including GSH (glutathione) and l‐Cys (l‐cysteine) are essential for cell signalling, growth and differentiation. l‐Cys is derived from the extracellular thiol pool and is the rate‐limiting compound for intracellular GSH biosynthesis. The present study investigated the effect of thiol‐supplemented medium on cell growth, phenotype and total GSH of cultured hPMCs (human peritoneal mesothelial cells). Cells were cultured in medium M199 supplemented with 2% serum, with ‘plus’ or without ‘minus’ l‐Cys and compared with medium supplemented with either β‐ME (β‐mercaptoethanol) (0.25 mmol/l) or the receptor tyrosine kinase ligand EGF (epidermal growth factor, 100 ng/ml). β‐ME produced a disproportionate increase in total GSH compared with l‐Cys and other thiols tested [(procysteine (2‐oxothiazolidine‐4‐carboxylic acid) or NAC (N‐acetyl‐l‐cysteine)], while growth and morphology were identical. Cell behaviour of primary hPMCs is characterized by the transition of fibroblastoid to cobblestone morphology during early passage. l‐Cys and β‐ME promoted a rapid MET (mesenchymal‐to‐epithelial transition) within 3 days of culture, confirmed by the presence of cobblestone cells, intact organelles, abundant microvilli, primary cilia and cortical actin. In contrast, EGF produced a biphasic response consisting of delayed growth and retention of a fibroblastoid morphology. During a rapid log phase of growth, MET was accompanied by rapid catch‐up growth. Thiols may stabilize the epithelial phenotype by engaging redox‐sensitive receptors and transcription factors that modulate differentiation. These data may benefit researchers working on thiol‐mediated cell differentiation and strategies to regenerate damage to serosal membranes.
Effect of calcitonin gene‐related peptide on nitric oxide production in osteoblasts: an experimental study
Authors: Yan Li , Yinghui Tan , Bo Yang , Gang Zhang , Xian Xiao , Lu Zheng 
Published: March 2011

AbstractThe aim of this study was to investigate the in vitro effects and regulatory mechanism of CGRP (calcitonin gene‐related peptide) on NO (nitric oxide) production in osteoblasts. MOB (primary human mandibular osteoblasts) and osteoblast‐like cells (MG‐63) were either cultured with CGRP or co‐incubated with inhibitors targeting eNOS (endothelial nitric oxide synthase), iNOS (inducible nitric oxide synthase), nNOS (neuronal nitric oxide synthase) and [Ca2+]i (intracellular Ca2+). The NO concentration in cell culture supernatants was measured during the first 24 h using the Griess test; cellular NO was marked with the fluorescent marker DAF‐FM, DA (3‐amino, 4‐aminomethyl‐2′,7′‐difluorescein; diacetate) and measured by fluorescence microscopy from 1 to 4 h after treatment. eNOS and iNOS mRNA expression levels were measured by quantitative RT‐PCR during the first 24 h after treatment. CGRP‐induced NO production in the supernatants was high between 1 to 12 h, while cellular NO was highest between 1 to 2 h after treatment and returned to basal levels by 3 h. Both in MG‐63 cells and MOBs, the most effective CGRP concentration was 10 nM with a peak time of 1 h. CGRP‐induced NO production decreased when eNOS activity was inhibited or when voltage‐dependent L‐type Ca2+ channels were blocked at 4 h. CGRP was not able to induce changes in iNOS or eNOS mRNA levels and had no effect on the cytokine‐induced increase of iNOS expression. Our results suggest that CGRP transiently induces NO production in osteoblasts by elevating intracellular Ca2+ to stimulate the activity of eNOS in vitro.
Seroepidemiology of Chronic Fatigue Syndrome: A Case-Control Study
Authors: Mawle Alison C. , Nisenbaum Rosane , Dobbins James G. , Gary Howard E. , Stewart John A. , Reyes Michele , Steele Lea , Schmid D. Scott , Reeves William C. 
Published: March 2011

Abstract
We performed serological testing for a large number of infectious agents in 26 patients from Atlanta who had chronic fatigue syndrome (CFS) and in 50 controls matched by age, race, and sex. We did not find any agent associated with CFS. In addition, we did not find elevated levels of antibody to any of a wide range of agents examined. In particular, we did not find elevated titers of antibody to any herpesvirus, nor did we find evidence of enteroviral exposure in this group of patients.
Impact of Pediatric Rome III Criteria of Functional Dyspepsia on the Diagnostic Yield of Upper Endoscopy and Predictors for a Positive Endoscopic Finding
Authors: Tam Yuk Him , Chan Kin Wai , To Ka Fai , Cheung Sing Tak , Mou Jennifer Wai Cheung , Pang Kristine Kit Yi , Wong Yuen Shan , Sihoe Jennifer Dart Yin , Lee Kim Hung 
Published: March 2011

ABSTRACTObjective:Pediatric Rome III criteria of functional dyspepsia (FD) has eliminated the mandatory use of upper endoscopy and recommended a symptom‐based approach. In the absence of alarm symptoms, FD can be positively diagnosed in children having normal physical findings without exclusionary investigations. We aimed to investigate the effectiveness of Rome III guidelines to discriminate organic diseases from FD and to identify the predictors for positive endoscopic findings.Patients and Methods:A prospective study was conducted on consecutive children fulfilling Rome III criteria of FD. Upper endoscopy was performed in all subjects, both with and without alarm features.Results:Eighty consecutive children ages 7 to 15 were recruited. Nine (11.3%) had experienced alarm features. Five (6.3%) had organic diseases confirmed in upper endoscopy: duodenal ulcer (n = 2), duodenitis with erosion (n = 2), and gastritis with erosion (n = 1), 33.3% of children having alarm features had organic pathology, compared with 2.8% of those without (P < 0.01). A male predominance (80% vs 25.3%, P < 0.01), higher prevalence of alarm features (60% vs 8%, P < 0.01), and higher prevalence of Helicobacter pylori infection (80% vs 5.3%, P < 0.01) were found in children with organic diseases, compared with FD. Multivariate analysis identified H pylori infection (odds ratio 23.2; 95% confidence interval 1.5–333) and nocturnal pain (odds ratio 26.3; 95% confidence interval 1.2–500) to be independent predictors for positive endoscopic findings.Conclusions:Rome III recommendations of screening dyspeptic children for alarm features and investigation for H pylori are effective to identify children who have a higher likelihood of organic diseases and require upper endoscopy before making a diagnosis of FD.
Socio‐demographic factors influence the attitudes of local residents towards trophy hunting activities in the Kilombero Valley, Tanzania
Authors: Jew Eleanor , Bonnington Colin 
Published: March 2011

AbstractWithin the Kilombero Game Controlled Area (KGCA) of Tanzania, protection is offered to large mammal populations by trophy hunting concessions that maintain natural habitat through the prevention of extensive human encroachment. The opinions of local communities to wildlife management operations such as trophy hunting play an important role in their long‐term viability. This study addresses the influence of socio‐demographic factors on the opinions of local communities to trophy hunting in areas that are not part of community‐based management projects, which is where most research of this type has previously been conducted. Semi‐structured questionnaires were conducted in 24 villages within the Kilombero Valley (fifteen interviews per village) in August–December 2007. The extent to which socio‐demographic factors including location (e.g. village of residence) and individual respondent characteristics (e.g. gender and age) influenced the respondents’ opinions was analysed. Of these socio‐demographic factors, all, except age and district of residence, were found to influence the opinions of local residents.Socio‐demographic factors play an important role in determining local communities’ attitudes towards trophy hunting, and this must be taken into account during the design and assessment of wildlife management conservation strategies, both locally in the KGCA and in similar national and international initiatives.
Efficacy and safety of home-based subcutaneous immunoglobulin replacement therapy in paediatric patients with primary immunodeficiencies
Authors:   Vivaglobin Study Group, Borte M , Bernatowska E , Ochs H D , Roifman C M 
Published: March 2011

Summary
Subcutaneous immunoglobulin infusions are effective, safe and well tolerated in the treatment of primary immunodeficiencies, but only limited data on the treatment of children are available. We investigated the efficacy, safety and pharmacokinetics of home therapy with a 16% liquid human immunoglobulin G preparation (Vivaglobin®) when administered subcutaneously in children with primary immunodeficiencies. Data were analysed from 22 children (2–&lt;12 years) who participated in two prospective, open-label studies (one in Europe/Brazil, one in North America). All children had previously received intravenous immunoglobulins. They started weekly subcutaneous immunoglobulin infusions with an approximately 3-month wash-in/wash-out period, followed by a 6-month (Europe/Brazil) or 12-month (North America) efficacy evaluation period. In Europe/Brazil, subcutaneous doses generally equalled the previous weekly equivalent intravenous doses. In North America, subcutaneous doses during the efficacy evaluation period were 126% (median) of the previous weekly equivalent intravenous doses. Efficacy end-points in both studies included the occurrence of serious bacterial infections and any infections, and serum immunoglobulin G trough levels. Median serum immunoglobulin G trough levels exceeded those during previous intravenous therapy by 13% (North America) and 16% (Europe/Brazil). During the efficacy evaluation period of both studies, none of the children had a serious bacterial infection; the mean overall infection rate/patient year was 4·7 in Europe/Brazil and 5·6 in North America, concurring with previous reports in adults. The adverse event profile was comparable to previous reports in adults. Both studies confirmed the efficacy and safety of subcutaneous immunoglobulin therapy with Vivaglobin in children with primary immunodeficiencies.
Kin structure and genotype‐dependent mortality: a study using the neotropical tree Caryocar brasiliense
Authors: Collevatti Rosane G. , Hay John D. 
Published: March 2011

Summary 1. In many species, density‐dependent processes regulate population size through size‐ and neighbourhood‐dependent mortality. 2. If a kin structure exists in a particular population, mortality may be spatially clustered due to enhanced competition among relatives. 3. Demography, kin structure and genetic diversity, based on 10 microsatellite loci, of a local population of the Neotropical tree Caryocar brasiliense were studied for 23 years. Overall population growth was static (λ = 1.0) during this time, but some time intervals showed negative growth. 4. Mortality was spatially clustered and negatively correlated with spatial distance among pairs of individuals at distances lower than c. 13 m. Probability of death was related to individual genotypes, and seedlings and juveniles with lower proportion of heterozygous loci had the highest probability of mortality. 5. Kinship was significantly related to spatial distance among pairs of individuals at distance lower than 10 m and kinship structure did not change along the life stages, but the inbreeding coefficient was not significantly different from zero in adults. 6. Synthesis. We hypothesize that genetic clustering in C. brasiliense dissipates over time due to more intense competition among relatives. Thus, the kin structure in C. brasiliense is highly important in determining mortality patterns, driving the spatial pattern in plant recruitment.
Heterozygosity–fitness correlations among wild populations of European tree frog (Hyla arborea) detect fixation load
Authors: LUQUET E. , DAVID P. , LENA J.‐P. , JOLY P. , KONECNY L. , DUFRESNES C. , PERRIN N. , PLENET S. 
Published: March 2011

AbstractQuantifying the impacts of inbreeding and genetic drift on fitness traits in fragmented populations is becoming a major goal in conservation biology. Such impacts occur at different levels and involve different sets of loci. Genetic drift randomly fixes slightly deleterious alleles leading to different fixation load among populations. By contrast, inbreeding depression arises from highly deleterious alleles in segregation within a population and creates variation among individuals. A popular approach is to measure correlations between molecular variation and phenotypic performances. This approach has been mainly used at the individual level to detect inbreeding depression within populations and sometimes at the population level but without consideration about the genetic processes measured. For the first time, we used in this study a molecular approach considering both the interpopulation and intrapopulation level to discriminate the relative importance of inbreeding depression vs. fixation load in isolated and non‐fragmented populations of European tree frog (Hyla arborea), complemented with interpopulational crosses. We demonstrated that the positive correlations observed between genetic heterozygosity and larval performances on merged data were mainly caused by co‐variations in genetic diversity and fixation load among populations rather than by inbreeding depression and segregating deleterious alleles within populations. Such a method is highly relevant in a conservation perspective because, depending on how populations lose fitness (inbreeding vs. fixation load), specific management actions may be designed to improve the persistence of populations.
Expression of the ompATb operon accelerates ammonia secretion and adaptation of Mycobacterium tuberculosis to acidic environments
Authors: Song Houhui , Huff Jason , Janik Katharine , Walter Kerstin , Keller Christine , Ehlers Stefan , Bossmann Stefan H. , Niederweis Michael 
Published: March 2011

SummaryHomeostasis of intracellular pH is a trait critical for survival of Mycobacterium tuberculosis in macrophages. However, mechanisms by which M. tuberculosis adapts to acidic environments are poorly understood. In this study, we analysed the physiological functions of OmpATb, a surface‐accessible protein of M. tuberculosis. OmpATb did not complement the permeability defects of a Mycobacterium smegmatis porin mutant to glucose, serine and glycerol, in contrast to the porin MspA. Uptake rates of these solutes were unchanged in an ompATb operon mutant of M. tuberculosis indicating that OmpATb is not a general porin. Chemical analysis of low‐pH culture filtrates showed that the proteins encoded by the ompATb operon are involved in generating a rapid ammonia burst, which neutralized medium pH and preceded exponential growth of M. tuberculosis. Addition of ammonia accelerated growth of the ompATb operon mutant demonstrating that ammonia secretion is indeed a mechanism by which M. tuberculosis neutralizes acidic environments. Infection experiments revealed that the ompATb operon was not required for full virulence in mice suggesting that M. tuberculosis has multiple mechanisms of resisting phagosomal acidification. Taken together, these results show that the ompATb operon is necessary for rapid ammonia secretion and adaptation of M. tuberculosis to acidic environments in vitro but not in mice.
Effect of GABA‐ergic mechanisms on synaptosomal NO synthesis and the nitrergic component of NANC relaxation in rat ileum
Authors: Kurjak M. , Fichna J. , Harbarth J. , Sennefelder A. , Allescher H. D. , Schusdziarra V. , Storr M. , Otto B. 
Published: March 2011

AbstractBackground γ‐Aminobutyric acid (GABA) acts on specific neural receptors [A, B and C(Aρ)] to modulate gastrointestinal function. The precise role of GABA receptor activation in the regulation of presynaptic nitric oxide (NO) synthesis in nerve terminals is unknown.Methods Rat ileal nerve terminals were isolated by differential centrifugation. Nitric oxide synthesis was analysed using a L‐[3H]arginine assay. In vitro studies were performed under non‐adrenergic non‐cholinergic (NANC) conditions on isolated ileal segments.Key Results γ‐Aminobutyric acid inhibited NO synthesis significantly (n = 6, P < 0.05) [(fmol mg−1 min−1) control: 27.7 ± 1.5, 10−6 mol L−1: 19.7 ± 1.3; 10−5 mol L−1: 17.5 ± 3.0]. This effect was antagonized by the GABA A receptor antagonist bicuculline and the GABA C receptor antagonist (1,2,5,6‐tetrahydropyridin‐4‐yl)methylphosphinic acid (TPMPA), but not by the GABA B receptor antagonist SCH 50911. The GABA A receptor agonist muscimol [(fmol mg−1 min−1) control: 27.6 ± 1.0, 10−6 mol L−1: 19.1 ± 1.7, n = 5, P < 0.05] and the GABA C receptor agonist cis‐4‐aminocrotonic acid (CACA) [(fmol mg−1 min−1) control: 29.5 ± 3.2, 10−3 mol L−1: 20.3 ± 2.5, n = 6, P < 0.05], mimicked the GABA‐effect, whereas the GABA B agonist baclofen was ineffective. Bicuculline reversed the inhibitory effect of muscimol, TPMPA antagonized the effect of CACA. In functional experiments the GABA A and C receptor agonists reduced the NANC relaxation induced by electrical field stimulation in rat ileum by about 40%. After NOS‐inhibition by Nε‐nitro‐l‐arginine methyl ester (l‐NAME) the GABA A receptor agonist had no effect, whereas the GABA C receptor agonist still showed a residual response.Conclusions & Inferences γ‐Aminobutyric acid inhibits neural NO synthesis in rat ileum by GABA A and GABA C(Aρ) receptor‐mediated mechanisms.
Contrasting growth and adaptive responses of two oak species to flooding stress: role of non‐symbiotic haemoglobin
Authors: PARENT CLAIRE , CRÈVECOEUR MICHÈLE , CAPELLI NICOLAS , DAT JAMES F. 
Published: March 2011

ABSTRACTSoil flooding is an environmental constraint that is increasingly important for forest ecosystems, affecting tree growth and regeneration. As a result, selection pressure will alter forest diversity and distribution by favouring tree species tolerant of soil oxygen deprivation. Sessile and pedunculate oaks are the most abundant oak species and they exhibit a strong differential tolerance to waterlogging. In order to gain some understanding of the mechanisms of tolerance of both species to hypoxia, we undertook the characterization of the physiological, morphological, cellular and molecular responses of both species to flooding stress. Our results indicate that pedunculate oak, the more tolerant species, succeeded in maintaining its growth, water status and photosynthetic activity at a higher level than sessile oak. Furthermore, pedunculate oak developed aerenchyma in its root cortex as well as adventitious roots. The later exhibited a strong accumulation of class1 non‐symbiotic haemoglobin localized by in situ hybridization in the protoderm and in some cortical cells. In conclusion, the higher tolerance of pedunculate oak to flooding was associated with an enhanced capacity to maintain photosynthesis and water homeostasis, coupled with the development of adaptive features (aerenchyma, adventitious roots) and with a higher expression of non‐symbiotic haemoglobin in the roots.
The OzT8 locus in rice protects leaf carbon assimilation rate and photosynthetic capacity under ozone stress
Authors: CHEN CHARLES P. , FREI MICHAEL , WISSUWA MATTHIAS 
Published: March 2011

ABSTRACTTropospheric ozone (O3) is a phytotoxic air pollutant whose current background concentrations in parts of East Asia have caused estimated rice yield losses of up to 20%; currently, however, little is known about the mechanisms of O3 tolerance in rice. We previously identified a quantitative trait locus (QTL) in rice called OzT8, which was associated with relative dry weight under ozone stress. The photosynthetic response in SL46, a Nipponbare (NB)–Kasalath chromosome segment substitution line (SL) containing the OzT8 locus, was compared to the parent NB in multiple ozone fumigation experiments (100 ppb, 8 h d–1, 23 d). By day 23, SL46 showed significantly less reduction of photosynthetic capacity compared to NB; the maximum carboxylation rate of ribulose 1·5‐bisphosphate carboxylase/oxygenase (Rubisco) decreased by 24% in SL46 compared to 49% in NB, and the maximum electron transport rate decreased by 16 and 39%, respectively. The midday carbon assimilation rates also showed a similar trend, but there was no genotypic difference in stomatal conductance. These results indicate that the OzT8 locus confers ozone tolerance via biochemical acclimation, not avoidance, making it a potentially valuable target for breeding of ozone tolerance into future rice lines. The sequence of photosynthetic response of rice to ozone stress and related tolerance factors are also discussed.