bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth behaviour of small surface fatigue cracks in AISI 304 stainless steel
Authors: SUH C.‐M. , SUH M.‐S. , HWANG N.‐S. 
Published: October 2011

ABSTRACTA series of axial tensile fatigue tests (R = 0.1) was carried out to investigate the initiation and the growth behaviours of very small surface fatigue cracks under two different surface conditions (viz. smooth and pitted surfaces) of AISI 304 stainless steel at room temperature. This paper deals with both of the two approaches regarding the analysis of fatigue: the approach based on the concept of fracture mechanics and low cycle fatigue. In particular, both the initiation and growth of cracks and the coalescence of small cracks by fatigue in the specimen have been investigated by the methods of surface replicas and photomicrographs. Quantitative information such as the initiation period, growth and coalescence behaviours of small cracks, and crack growth properties were systematically obtained. The results show that the accurate determination of these parameters is critical for the application of fracture mechanics to fatigue life assessment.
Theta synchronization in the limbic system: the role of Gudden's tegmental nuclei
Authors: Kocsis Bernat , Di Prisco Gonzalo Viana , Vertes Robert P. 
Published: October 2011

AbstractTheta rhythm is most prominent in the hippocampus but has also been recorded in other cortical and limbic structures and can play an important role in functional coupling of widely separated structures responsible for different components of the memory building process. Here we demonstrate in the rat that neuronal activity exhibiting strong state‐dependent synchrony with rhythmic hippocampal electroencephalogram is present also at the brainstem level, specifically in the relatively small tegmental nuclei of Gudden intimately connected with the limbic forebrain. We found that during theta states, either occurring spontaneously or triggered by sensory stimulation in the urethane anaesthetized rat, all neurons in the anterior and ventral tegmental nuclei exhibited a consistent switch from irregular discharges to rhythmic bursts. The switch between these patterns closely matched the analogous transformations in the hippocampal EEG, but the level of synchrony between the two signals varied depending on the level of theta activation. During sensory stimulation, when theta is faster and more regular, the rhythmic bursts in the tegmentum showed extremely high coherence (up to 0.96) with hippocampal field potentials. During spontaneous theta, the average coherence was lower but still highly significant (0.62). Gudden's nuclei are reciprocally connected to the mammillary body complex (MB) occupying a strategic position at the gateway of hippocampofugal connections organized in the Papez circuit. Thus, coupling between the MB‐Gudden circuit and the hippocampus and consequently the neuronal traffic through the Papez circuit and hence the assembly of limbic structures connected to the hippocampus may vary according to the activity in these specific brainstem nuclei.
Enterobactin is required for biofilm development in reduced‐genome Escherichia coli
Authors: May Thithiwat , Okabe Satoshi 
Published: October 2011

SummaryA variety of bacterial cell surface structures and quorum signalling molecules play a role in biofilm development in Escherichia coli. However, here we show that an engineered reduced‐genome E. coli mutant that lacks 17.6% of the parental E. coli genome, including the genes involved in the synthesis of various cell surface structures, such as type 1 fimbriae, curli, exopolysaccharide polymers and the autoinducer‐2 signalling molecule, is able to develop mature biofilms. Using temporal gene expression profiling, we investigated phenotypic changes in reduced‐genome biofilms in relation with the genes encoding the synthesis of different amino acids that were differentially expressed during biofilm formation. We identified and characterized entB, marR, dosC, mcbR and yahK genes, as involved in biofilm formation by the reduced‐genome E. coli. Of these, for a first time, we demonstrated that overproduction of entB and yahK, which encode an enterobactin for iron transport and a hypothetical oxidoreductase protein, respectively, promoted biofilm development and maturation. Our results indicate that specific types of genes contribute to phenotypic changes in reduced‐genome E. coli biofilms. In addition, this work demonstrates that the functions of biofilm‐specific genes could be analysed through experiments using the reduced‐genome E. coli.
Polyphyly of non‐bioluminescent Vibrio fischeri sharing a lux‐locus deletion
Authors: Wollenberg M. S. , Preheim S. P. , Polz M. F. , Ruby E. G. 
Published: October 2011

SummaryThis study reports the first description and molecular characterization of naturally occurring, non‐bioluminescent strains of Vibrio fischeri. These ‘dark’V. fischeri strains remained non‐bioluminescent even after treatment with both autoinducer and aldehyde, substrate additions that typically maximize light production in dim strains of luminous bacteria. Surprisingly, the entire lux locus (eight genes) was absent in over 97% of these dark V. fischeri strains. Although these strains were all collected from a Massachusetts (USA) estuary in 2007, phylogenetic reconstructions allowed us to reject the hypothesis that these newly described non‐bioluminescent strains exhibit monophyly within the V. fischeri clade. These dark strains exhibited a competitive disadvantage against native bioluminescent strains when colonizing the light organ of the model V. fischeri host, the Hawaiian bobtail squid Euprymna scolopes. Significantly, we believe that the data collected in this study may suggest the first observation of a functional, parallel locus‐deletion event among independent lineages of a non‐pathogenic bacterial species.
Empagliflozin, a novel selective sodium glucose cotransporter‐2 (SGLT‐2) inhibitor: characterisation and comparison with other SGLT‐2 inhibitors
Authors: Grempler R. , Thomas L. , Eckhardt M. , Himmelsbach F. , Sauer A. , Sharp D. E. , Bakker R. A. , Mark M. , Klein T. , Eickelmann P. 
Published: October 2011

Aims: Empagliflozin is a selective sodium glucose cotransporter‐2 (SGLT‐2) inhibitor in clinical development for the treatment of type 2 diabetes mellitus. This study assessed pharmacological properties of empagliflozin in vitro and pharmacokinetic properties in vivo and compared its potency and selectivity with other SGLT‐2 inhibitors.Methods: [14C]‐alpha‐methyl glucopyranoside (AMG) uptake experiments were performed with stable cell lines over‐expressing human (h) SGLT‐1, 2 and 4. Two new cell lines over‐expressing hSGLT‐5 and hSGLT‐6 were established and [14C]‐mannose and [14C]‐myo‐inositol uptake assays developed. Binding kinetics were analysed using a radioligand binding assay with [3H]‐labelled empagliflozin and HEK293‐hSGLT‐2 cell membranes. Acute in vivo assessment of pharmacokinetics was performed with normoglycaemic beagle dogs and Zucker diabetic fatty (ZDF) rats.Results: Empagliflozin has an IC50 of 3.1 nM for hSGLT‐2. Its binding to SGLT‐2 is competitive with glucose (half‐life approximately 1 h). Compared with other SGLT‐2 inhibitors, empagliflozin has a high degree of selectivity over SGLT‐1, 4, 5 and 6. Species differences in SGLT‐1 selectivity were identified. Empagliflozin pharmacokinetics in ZDF rats were characterised by moderate total plasma clearance (CL) and bioavailability (BA), while in beagle dogs CL was low and BA was high.Conclusions: Empagliflozin is a potent and competitive SGLT‐2 inhibitor with an excellent selectivity profile and the highest selectivity window of the tested SGLT‐2 inhibitors over hSGLT‐1. Empagliflozin represents an innovative therapeutic approach to treat diabetes.
The relationship between obesity and hypoferraemia in adults: a systematic review
Authors: Cheng H. L. , Bryant C. , Cook R. , O'Connor H. , Rooney K. , Steinbeck K. 
Published: October 2011

SummaryA growing number of studies suggest a potential link between obesity and altered iron metabolism. The purpose of this systematic review was to examine existing literature on iron status in obese populations. A comprehensive literature search was conducted. Included studies recruited participants ≥ 18 years with a body mass index ≥ 30 kg m−2 and provided descriptive statistics for haemoglobin or ferritin at a minimum. There were 25 studies meeting all eligibility criteria, of these 10 examined iron status in free‐living obese individuals and 15 reported baseline iron biomarkers from bariatric surgery candidates. Non‐obese comparison groups were used by 10 (40%) articles. In these, seven obese groups reported higher mean haemoglobin concentration; six reported significantly higher ferritin concentration; and four significantly lower transferrin saturation. Due to insufficient data, it was not possible to make conclusions regarding mean differences for soluble transferrin receptor (sTfR), hepcidin or C‐reactive protein. Existing evidence suggests a tendency for higher haemoglobin and ferritin concentration and lower transferrin saturation in obesity. Alternation of iron biomarkers in obese populations may be a result of obesity‐related inflammation and/or related comorbidities. Further research incorporating measurement of inflammatory cytokines, sTfR and hepcidin is required to confirm the impact of obesity on iron status.
Flexible Semiparametric Analysis of Longitudinal Genetic Studies by Reduced Rank Smoothing
Authors: Wang Yuanjia , Huang Chiahui , Fang Yixin , Yang Qiong , Li Runze 
Published: October 2011

SummaryIn longitudinal genetic studies, investigators collect repeated measurements on a trait that changes with time along with genetic markers. For family-based longitudinal studies, since repeated measurements are nested within subjects and subjects are nested within families, both the subject level and the measurement level correlations must be taken into account in the statistical analysis to achieve more accurate estimation. In such studies, the primary interests include testing for a quantitative trait locus effect, and estimating the age-specific quantitative trait locus effect and residual polygenic heritability function. We propose flexible semiparametric models and their statistical estimation and hypothesis testing procedures for longitudinal genetic data. We employ penalized splines to estimate non-parametric functions in the model. We find that misspecifying the baseline function or the genetic effect function in a parametric analysis may lead to a substantially inflated or highly conservative type I error rate on testing and large mean-squared error on estimation. We apply the proposed approaches to examine age-specific effects of genetic variants reported in a recent genomewide association study of blood pressure collected in the Framingham Heart Study.
Evaluation of the efficacy and safety of a CS20® protective barrier gel containing OGT compared with topical aciclovir and placebo on functional and objective symptoms of labial herpes recurrences: a randomized clinical trial
Authors: Khemis A. , Duteil L. , Coudert A.C. , Tillet Y. , Dereure O. , Ortonne J.P. 
Published: October 2011

AbstractBackground  Topical or systemic antiviral drugs reduce the duration of herpes simplex virus 1 (HSV‐1) recurrences but may not alleviate functional symptoms.Objectives  To assess the efficacy and safety of CS20 (Acura 24®) protective barrier gel versus topical aciclovir and placebo in resolving functional symptoms in HSV‐1 labial recurrences.Methods  A prospective, randomized, single‐centre, assessor‐blinded study of CS20 versus topical aciclovir or placebo. The primary endpoint was the total score of four herpes‐related functional symptoms (pain, burning, itching, and tingling sensations), evaluated by visual analogue scale (VAS). Secondary endpoints encompassed objective skin changes (oedema, crusting and erythema), evaluated by specific clinical scores.Results  In a study of 106 patients, compared with placebo, a significant improvement in total functional symptom score was observed after 1 day of treatment in the CS20 group, but only after 7 days of treatment in the topical aciclovir group. Burning sensations were significantly reduced by CS20 compared with aciclovir (Days 1–2) or placebo (Days 1–7). Compared to placebo, CS20 significantly reduced pain intensity on Days 1–6. CS20 induced significant and early improvements in the clinical scores for oedema and crusting compared with placebo. Time to cure was similar for CS20 and aciclovir. The treatments were well tolerated and adverse events were comparable in the three treatment groups.Limitations  The single‐centre and single‐blind design of the study and the preselection of patients.Conclusion  CS20 showed superior effectiveness against functional symptoms (pain and burning) associated with HSV‐1 labial recurrences and was similar to aciclovir for time to cure.
Insulin‐like growth factor‐I gene polymorphism in acne vulgaris
Authors: Tasli L. , Turgut S. , Kacar N. , Ayada C. , Coban M. , Akcilar R. , Ergin S. 
Published: October 2011

AbstractBackground  Acne vulgaris is a multifactorial disease of the skin. Several studies have shown that elevated levels of serum insulin‐like growth factor‐I (IGF‐I) correlate with overproduction of sebum and acne. Recently functional relationship between IGF‐I (CA) polymorphism and circulating IGF‐I levels in adults has been reported.Aims  The aim of our study was to investigate for the first time whether IGF‐I (CA) polymorphism might be involved in the pathogenesis of acne or not.Methods  We included 115 acne patients and 117 healthy subjects to the study. The clinical grade of acne was assessed based on the Global Acne Grading System. Participants were questioned about diabetes mellitus, PCOS and other systemic disease. We searched for the IGF‐I (CA) 19 polymorphism in this study. The IGF‐I (CA) 19 polymorphism was performed by polymerase chain reaction.Results  We categorized the IGF‐I (CA) 19 polymorphism area into three groups as lower than 192 bp, 192–194 bp and higher than 194 bp. We found that the frequency of genotype IGF‐1 (CA) 19 gene was significantly different between control and acne patients (P = 0.0002). A significant association between IGF‐I (CA) genotypes and severity of acne was found (P = 0.015). No significant difference was found between male and female patients (P > 0.05).Conclusions  Our results suggest that IGF‐I (CA) 19 polymorphism may contribute to a predisposition to acne in Turkish patients.
Is it better in the moonlight? Nocturnal activity of insular cottonmouth snakes increases with lunar light levels
Authors: Lillywhite H. B. , Brischoux F. 
Published: October 2011

AbstractBoth theoretical and empirical investigations suggest that predation risk and availability of resources interact as trade‐offs to produce patterns of predation‐sensitive foraging. Such interactions have been explored intensely in terrestrial predator–prey systems where both nocturnal prey and predators adjust their activity and foraging behaviour to levels of moonlight. In the case of prey, higher levels of moonlight increase predation risks, and thus prey display lower levels of activity and/or shifts in their use of microhabitat during full moon nights. Predators also display parallel modifications of their activity rhythms during full moon nights – but why? Are predators also sensitive to increased predation, or do predators adjust their behaviour to that of their prey in order to optimize foraging success? Herein, we examined nocturnal predatory behaviour in a natural system where insular cottonmouth snakes, Agkistrodon piscivorus conanti, forage for fish carrion that is indifferent to levels of moonlight, thereby removing complexities linked to the behavioural patterns of prey. Our results demonstrated that insular cottonmouths increase their activity during full moon nights. Predation pressure on snakes foraging in the open does not seem to drive their nocturnal behaviour insofar as small‐sized individuals – presumably more susceptible to predation – are equally abundant as adult snakes irrespective of levels of moonlight. These results suggest that variation in predator's activity in natural predator–prey systems during risky (full moon) nights might be attributable principally to the availability and detectability of prey rather than a foraging‐safety trade‐off specific to the predator.
Risk of recurrence and subsequent delivery after obstetric anal sphincter injuries
Authors: Baghestan E , Irgens LM , Børdahl PE , Rasmussen S 
Published: October 2011

Please cite this paper as: Baghestan E, Irgens L, Børdahl P, Rasmussen S. Risk of recurrence and subsequent delivery after obstetric anal sphincter injuries. BJOG 2012;119:62–69.Objective  To investigate the recurrence risk, the likelihood of having further deliveries and mode of delivery after third to fourth degree obstetric anal sphincter injuries (OASIS).Design  Population‐based cohort study.Setting  The Medical Birth Registry of Norway.Population  A cohort of 828 864 mothers with singleton, vertex‐presenting infants, weighing 500 g or more, during the period 1967–2004.Methods  Comparison of women with and without a history of OASIS with respect to the occurrence of OASIS, subsequent delivery rate and planned caesarean rate.Main outcome measures  OASIS in second and third deliveries, subsequent delivery rate and mode of delivery.Results  Adjusted odds ratios of the recurrence of OASIS in women with a history of OASIS in the first, and in both the first and second deliveries, were 4.2 (95% CI 3.9–4.5; 5.6%) and 10.6 (95% CI 6.2–18.1; 9.5%), respectively, relative to women without a history of OASIS. Instrumental deliveries, in particular forceps deliveries, birthweights of 3500 g or more and large maternity units were associated with a recurrence of OASIS. Instrumental delivery did not further increase the excess recurrence risk associated with high birthweight. A man who fathered a child whose delivery was complicated by OASIS was more likely to father another child whose delivery was complicated by OASIS in another woman who gave birth in the same maternity unit (adjusted OR 2.1; 95% CI 1.2–3.7; 5.6%). However, if the deliveries took place in different maternity units, the recurrence risk was not significantly increased (OR 1.3; 95% CI 0.8–2.1; 4.4%). The subsequent delivery rate was not different in women with and without previous OASIS, whereas women with a previous OASIS were more often scheduled to caesarean delivery.Conclusion  Recurrence risks in second and third deliveries were high. A history of OASIS had little or no impact on the rates of subsequent deliveries. Women with previous OASIS were delivered more frequently by planned caesarean delivery.
Impact of mode of delivery on levator morphology: a prospective observational study with three‐dimensional ultrasound early in the postpartum period
Authors: Albrich SB , Laterza RM , Skala C , Salvatore S , Koelbl H , Naumann G 
Published: October 2011

Please cite this paper as: Albrich S, Laterza R, Skala C, Salvatore S, Koelbl H, Naumann G. Impact of mode of delivery on levator morphology: a prospective observational study with three‐dimensional ultrasound early in the postpartum period. BJOG 2012;119:51–61.Objective  To evaluate morphology and integrity of the levator ani muscle (LAM) with three‐dimensional ultrasound early in the postpartum period.Design  Prospective cross‐sectional observational study.Setting  University hospital in Germany.Population  Women after vaginal delivery and caesarean section with no previous vaginal delivery.Methods  Three‐dimensional perineal ultrasound was performed between 48 and 72 hours postpartum. The axial plane at the level of minimal hiatal dimension and tomographic ultrasound imaging were used to determine LAM biometry and defect.Main outcome measures  Primary outcome was to compare hiatal dimensions and levator defect following vaginal delivery or caesarean section. For secondary outcomes, we evaluated the role of caesarean section in protecting levator integrity, and the possible involvement of the first stage of labour in LAM changes.Results  In all, 157 women participated: 81 (51.6%) following vaginal delivery (70 spontaneous and 11 operative deliveries) and 76 (48.4%) following caesarean section (55 elective and 21 emergency caesarean sections). All biometric indices of the levator were higher after vaginal delivery (P < 0.001), except for LAM thickness. LAM defects were found to be significantly associated with vaginal delivery, with relative risk 7.5 (P < 0.001). Following vaginal delivery, 32 (39.5%) levator defects were found: 27 (38.5%) after spontaneous delivery and five (45.4%) after operative delivery. Four (5.2%) women had a levator defect following emergency caesarean section.Conclusion  Vaginal delivery modifies and damages the LAM: the risk of levator defect after vaginal delivery is more than seven times higher than after caesarean section. Despite this, emergency caesarean section seems to have no complete preventive effect on LAM trauma.
Phosphorylation of microtubule‐associated protein tau by AMPK‐related kinases
Authors: Yoshida Hirotaka , Goedert Michel 
Published: October 2011

J. Neurochem. (2012) 120, 165–176.AbstractMicrotubule‐associated protein tau is abnormally hyperphosphorylated in the intracellular filamentous inclusions seen in neurodegenerative disorders with dementia, such as Alzheimer’s disease and other tauopathies. Microtubule‐associated protein/microtubule‐affinity regulating kinases (MARKs) have previously been identified as kinases which phosphorylate KxGS motifs in the tandem repeats of tau. They are members of the 5′‐AMP‐activated protein kinase (AMPK)‐related kinases in the Ca2+/calmodulin‐dependent protein kinase group. In this study, we examined the ability of AMPK‐related kinases, brain‐specific kinases 1 and 2, maternal embryonic leucine‐zipper kinase, MARK1, and salt‐inducible kinase (SIK), to phosphorylate tau. We found that they phosphorylated S262 and S356 in KxGS motifs in the repeats of tau, thus resulting in immunoreactivity with antibody 12E8. MARK1 and SIK most effectively phosphorylated tau, and their down‐regulation resulted in a reduction of 12E8‐labelling. BX 795, an inhibitor of MARK1 and SIK, reduced 12E8‐immunolabelling of tau in rat cortical neurons. These findings reveal a significant contribution of AMPK‐related kinases to the phosphorylation of tau at S262/S356.