bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endogenous circannual rhythm in luteinizing hormone secretion: insight from signal analysis coupled with mathematical modelling
Authors: Vidal Alexandre , Médigue Claire , Malpaux Benoît , Clément Frédérique 
Published: November 2009

In sheep, as in many vertebrates, the seasonal pattern of reproduction is timed by the annual photoperiodic cycle, characterized by seasonal changes in the day length. The photoperiodic information is translated into a circadian profile of melatonin secretion. After multiple neuronal relays (within the hypothalamus), melatonin affects gonadotrophin-releasing hormone (GnRH) secretion, which in turn controls ovarian cyclicity. The pattern of GnRH secretion is mirrored by that of luteinizing hormone (LH) secretion, whose plasmatic level can be easily measured. We addressed the question of whether there exists an endogenous circannual rhythm in a tropical sheep (Blackbelly) population that exhibits clear seasonal ovarian activity when ewes are subject to temperate latitudes. We based our analysis on LH time series collected in the course of 3 years from ewes subject to a constant photoperiodic regime. Owing to intra- and interanimal variability and unequal sampling times, the existence of an endogenous rhythm is not straightforward. We have used time–frequency signal processing methods, and especially the smooth pseudo-Wigner–Ville distribution, to extract possible hidden rhythms from the data. To further investigate the low-frequency (LF) and high-frequency (HF) components of the signals, we have designed a simple mathematical model of the LH plasmatic level accounting for the effect of experimental sampling times. The model enables us to (i) confirm the existence of an endogenous circannual rhythm as detected by the LF signal component, (ii) investigate the action mechanism of the photoperiod on the pulsatile pattern of LH secretion (control of the interpulse interval), and (iii) conclude that the HF component is mainly due to the experimental sampling protocol.
Mathematical modelling of atherosclerosis as an inflammatory disease
Authors: El Khatib N. , Génieys S. , Kazmierczak B. , Volpert V. 
Published: November 2009

Atherosclerosis is an inflammatory disease. The atherosclerosis process starts when low-density lipoproteins (LDLs) enter the intima of the blood vessel, where they are oxidized (ox-LDLs). The anti-inflammatory response triggers the recruitment of monocytes. Once in the intima, the monocytes are transformed into macrophages and foam cells, leading to the production of inflammatory cytokines and further recruitment of monocytes. This auto-amplified process leads to the formation of an atherosclerotic plaque and, possibly, to its rupture. In this paper we develop two mathematical models based on reaction–diffusion equations in order to explain the inflammatory process. The first model is one-dimensional: it does not consider the intima’s thickness and shows that low ox-LDL concentrations in the intima do not lead to a chronic inflammatory reaction. Intermediate ox-LDL concentrations correspond to a bistable system, which can lead to a travelling wave that can be initiated by certain conditions, such as infection or injury. High ox-LDL concentrations correspond to a monostable system, and even a small perturbation of the non-inflammatory case leads to travelling-wave propagation, which corresponds to a chronic inflammatory response. The second model we suggest is two-dimensional: it represents a reaction–diffusion system in a strip with nonlinear boundary conditions to describe the recruitment of monocytes as a function of the cytokines’ concentration. We prove the existence of travelling waves and confirm our previous results, which show that atherosclerosis develops as a reaction–diffusion wave. The results of the two models are confirmed by numerical simulations. The latter show that the two-dimensional model converges to the one-dimensional one if the thickness of the intima tends to zero.
Synchrony in reaction–diffusion models of morphogenesis: applications to curvature-dependent proliferation and zero-diffusion front waves
Authors: Abbas Lamia , Demongeot Jacques , Glade Nicolas 
Published: November 2009

The paper presents the classical age-dependent approach of the morphogenesis in the framework of the von Foerster equation, in which we introduce a new constraint and study a new feature: (i) the new constraint concerns cell proliferation along the contour lines of the cell density, depending on the local curvature such as it favours the amplification of the concavities (like in the gastrulation process) and (ii) the new feature consists of considering, on the cell density surface, a remarkable line (the null mean Gaussian curvature line), on which the normal diffusion vanishes, favouring local coexistence of diffusing morphogens, metabolites or cells, and hence the auto-assemblages of these entities. Two applications to biological multi-agents systems are studied, gastrulation and feather morphogenesis.
Preparation of Insoluble GST Fusion Proteins
Authors: Rebay Ilaria , Fehon Richard G. 
Published: November 2009

INTRODUCTIONA wide variety of plasmid vectors are commercially available for the production of fusion proteins in bacterial cells. Most are also designed to incorporate a tag that allows affinity purification of the expressed fusion protein from bacterial cell extracts. The most commonly used are vectors that incorporate a portion of the glutathione-S-transferase (GST) enzyme that is able to bind to immobilized glutathione and vectors that use a polyhistidine tag which binds immobilized nickel ions with high affinity. This protocol describes preparation of an insoluble GST fusion protein, isolated using glutathione agarose beads.
Confocal Immunocytochemistry of Embryonic and Juvenile Hawaiian Bobtail Squid (Euprymna scolopes) Tissues
Authors: Lee Patricia N. , McFall-Ngai Margaret J. , Callaerts Patrick , de Couet H. Gert 
Published: November 2009

INTRODUCTIONThe Hawaiian bobtail squid Euprymna scolopes is a cephalopod whose small size, short lifespan, rapid growth, and year-round availability make it suitable as a model organism. This protocol describes the preparation of whole juvenile squids by whole-mount immunocytochemistry for visualization by confocal microscopy.
Culturing Meristematic Tissue and Node Cuttings from Yams (Dioscorea)
Authors: Mignouna Hodeba D. , Abang Mathew M. , Asiedu Robert , Geeta R. 
Published: November 2009

INTRODUCTIONThis protocol describes how to produce whole yam (Dioscorea) plantlets in vitro through yam meristem culture and from yam node cuttings.
Extraction of DNA from Yam (Dioscorea) Leaves
Authors: Mignouna Hodeba D. , Abang Mathew M. , Asiedu Robert , Geeta R. 
Published: November 2009

INTRODUCTIONThis protocol describes how to extract DNA from the leaves of true yams (Dioscorea) for polymerase chain reaction (PCR) and other analyses.
Breastfeeding promotion for infants in neonatal units: a systematic review
Authors: Renfrew M. J. , Dyson L. , McCormick F. , Misso K. , Stenhouse E. , King S. E. , Williams A. F. 
Published: November 2009

AbstractBackground  Breastfeeding/breastmilk feeding of infants in neonatal units is vital to the preservation of short‐ and long‐term health, but rates are very low in many neonatal units internationally. The aim of this review was to evaluate the effectiveness of clinical, public health and health promotion interventions that may promote or inhibit breastfeeding/breastmilk feeding for infants admitted to neonatal units.Methods  Systematic review with narrative synthesis. Studies were identified from structured searches of 19 electronic databases from inception to February 2008; hand searching of bibliographies; Advisory Group members helped identify additional sources. Inclusion criteria: controlled studies of interventions intended to increase breastfeeding/feeding with breastmilk that reported breastmilk feeding outcomes and included infants admitted to neonatal units, their mothers, families and caregivers. Data were extracted and appraised for quality using standard processes. Study selection, data extraction and quality assessment were independently checked. Study heterogeneity prevented meta‐analysis.Results  Forty‐eight studies were identified, mainly measuring short‐term outcomes of single interventions in stable infants. We report here a sub‐set of 21 studies addressing interventions tested in at least one good‐quality or more than one moderate‐quality study. Effective interventions identified included kangaroo skin‐to‐skin contact, simultaneous milk expression, peer support in hospital and community, multidisciplinary staff training, and Unicef Baby Friendly accreditation of the associated maternity hospital.Conclusions  Breastfeeding/breastmilk feeding is promoted by close, continuing skin‐to‐skin contact between mother and infant, effective breastmilk expression, peer support in hospital and community, and staff training. Evidence gaps include health outcomes and costs of intervening with less clinically stable infants, and maternal health and well‐being. Effects of public health and policy interventions and the organization of neonatal services remain unclear. Infant feeding in neonatal units should be included in public health surveillance and policy development; relevant definitions are proposed.
A longitudinal study of gastrointestinal diseases in individuals diagnosed with infantile autism as children
Authors: Mouridsen S. E. , Rich B. , Isager T. 
Published: November 2009

AbstractBackground  A number of studies have indicated a link between gastrointestinal (GI) diseases and autism spectrum disorders.Method  The objective of this study was to compare the prevalence and types of GI diseases in a clinical sample of 118 individuals diagnosed as children with infantile autism (IA) with GI diseases in 336 matched controls from the general population, based on data from the nationwide Danish National Hospital Register (DNHR). The average observation time was 30.3 years (SD 0.4) (range 27–30 years), and mean age at the end of the observation period was 42.7 years (SD 7.7) (range between 27 and 57 years of age).Results  Of the 118 individuals with IA, 97 (82.2%) had been in contact with a medical hospital (inpatient hospitalization or outpatient visits) during the observation period, compared with 312/336 (92.9%) in the control group (P= 0.001). A similar proportion of members from the case and comparison group had a diagnosis of any GI disease in the DNHR: 30.5% against 30.7%, but the nature of their diseases may be somewhat different. Only diseases of oral cavity were significantly associated with IA: 20.3% against 1.2%, P < 0.0001. Otherwise, specific GI diseases occurred with low frequency in both groups.Conclusion  Overall, no evidence was found that patients with IA were more likely than control persons without IA to have defined GI diseases during the 30.3‐year observation period.
Pollen‐derived low‐molecular weight factors inhibit 6‐sulfo LacNAc+ dendritic cells' capacity to induce T‐helper type 1 responses
Authors: Gilles S. , Jacoby D. , Blume C. , Mueller M. J. , Jakob T. , Behrendt H. , Schaekel K. , Traidl‐Hoffmann C. 
Published: November 2009

SummaryBackground
Evidence is accumulating that the pollen exsudate contains an array of non‐allergenic, pro‐inflammatory and immunomodulatory substances acting on the innate and adaptive immune system. In this context, pollen‐associated E1‐phytoprostanes (PPE1) were shown to licence human monocyte‐derived dendritic cells for T‐helper type 2 (Th2) polarization of naïve T cells.Objective
This study aims at analysing the impact of pollen‐associated lipid mediators on cytokine secretion and maturation of 6‐sulfo LacNAc+ dendritic cells (slanDCs), the most abundant native dendritic cell (DC) in human peripheral blood, and further dissecting the biologically active substance(s) within aqueous pollen extracts.Results
Aqueous birch pollen extracts dose‐dependently inhibited the lipopolysaccharide (LPS)‐induced IL‐12 p70 production, while the levels of IL‐6 remained unaffected. PPE1 inhibited secretion of both IL‐12 p70 and IL‐6. Aqueous pollen extracts, but not PPE1 or F1‐phytoprostanes significantly reduced the LPS‐induced surface expression of the maturation markers CD80, CD83, CD40 and CCR‐7, an effect that was independent of proteins and that was still present in a 3 kDa cut‐off fraction of the pollen extract. These effects were observed irrespective of the atopy status of the donors. Finally, slanDCs exposed to aqueous pollen extracts were impaired in eliciting an IFN‐γ response in naïve CD4+ T cells.Conclusion
Our data show that slanDCs, a subset of human blood DCs with constitutively high potency to induce Th1 responses, are susceptible to the Th2 polarizing effect of low molecular weight, non‐protein factors derived from pollen. Cite this as: S. Gilles, D. Jacoby, C. Blume, M. J. Mueller, T. Jakob, H. Behrendt, K. Schaekel and C. Traidl‐Hoffmann, Clinical & Experimental Allergy, 2010 (40) 269–278.
The role of paracetamol in the pathogenesis of asthma
Authors: Farquhar H. , Stewart A. , Mitchell E. , Crane J. , Eyers S. , Weatherall M. , Beasley R. 
Published: November 2009

SummaryParacetamol use represents a putative risk factor for the development of asthma. There is convincing epidemiological evidence that the risk of asthma may be increased with exposure to paracetamol in the intrauterine environment, infancy, later childhood and adult life. A dose‐dependent association has also been observed in these different age groups in different populations world‐wide. An association has also been shown between paracetamol use in both rhinoconjunctivitis and eczema. There is biological plausibility with paracetamol use leading to decreased glutathione levels resulting in increased oxidant‐induced inflammation and potentially enhanced T‐helper type 2 responses. At the population level, patterns of paracetamol use might explain, to some extent, the world‐wide variation in the prevalence of asthma and related disorders, particularly the high rates in English‐speaking countries, which have high per capita prescription and over‐the‐counter use of paracetamol. A temporal association also exists between the international trends of increasing paracetamol use and increasing prevalence of asthma over recent decades. Further research is urgently required, in particular randomized‐controlled trials (RCTs) into the long‐term effects of frequent paracetamol use in childhood, to determine the magnitude and characteristics of any such risk. Importantly, RCTs will also enable evidence‐based guidelines for the recommended use of paracetamol to be developed.Cite this as: H. Farquhar, A. Stewart, E. Mitchell, J. Crane, S. Eyers, M. Weatherall and R. Beasley,Clinical & Experimental Allergy, 2010 (40) 32–41.
Spring migration decisions in relation to weather are predicted by wing morphology among trans‐Mediterranean migratory birds
Authors: Saino Nicola , Rubolini Diego , Von Hardenberg Jost , Ambrosini Roberto , Provenzale Antonello , Romano Maria , Spina Fernando 
Published: November 2009

Summary1. Meteorological conditions are critical determinants of bird migration. However, response to weather should vary among species as well as between males and females, as phenotypic traits relevant to migration are also shaped by natural selection acting differentially on species and either sex in other life cycle phases.2. We studied the covariation between capture frequencies and meteorological conditions at departure and at a stopover site during northward spring migration in 21 species of migratory birds. The stopover site is a small island located at the northern end of a wide ecological barrier (the Mediterranen Sea), that is crossed with non‐stop flights by migrants departing from North Africa.3. Head and crosswinds at departure, and tail and crosswinds at stopover reduced the number of birds captured, although the strength of these effects varied among species. In the subset of 10 sexually dimorphic species, males and females were not differentially susceptible to weather conditions.4. Because sexual and natural selection pressures on traits relevant to migration vary among species, we investigated whether body mass and wing morphology predicted species susceptibility to weather in analyses controlling for phylogenetic effects, using wing loading, wing aspect ratio, the ‘brachial index’, and wingtip roundedness and convexity as indicators of the morphology of the flight apparatus.5. Captures of species whose wing morphology is more typical of long‐distance migrants were less affected by tail and crosswinds, suggesting that long‐distance migrants are less susceptible to weather.6. Meteorological conditions at departure independently concurred with those at stopover in determining capture frequencies. The effect of weather on migration covaried with wing morphological traits that co‐evolved with migratory strategies. Changes in meteorological conditions driven by current climate change thus have the potential to differentially affect migration phenology in relation to migratory strategy and morphology of individual species.
Ultraviolet crown colouration affects contest outcomes among male blue tits, but only in the absence of prior encounters
Authors: Vedder Oscar , Schut Elske , Magrath Michael J. L. , Komdeur Jan 
Published: November 2009

Summary 1. Static animal colour patches may function among competitors to minimize conflict escalation over resources, by serving as a signal of resource holding potential or aggressiveness. Empirical evidence for the use of colour patches in conflict resolution is largely restricted to pigment‐based colours (melanins and carotenoids) and rarely defines the context in which the signals are used. 2. Here we test whether structural‐based ultraviolet (UV) crown colouration functions in conflict resolution among dyads of first‐year male blue tits Cyanistes caeruleus in captivity, in a context that is known to favour aggressive individuals. 3. We found that on first encounter in a pairwise context, experimentally UV‐reduced males were significantly more likely to lose to control‐treated opponents than expected by chance. However, this disparity was less pronounced when conflicts were settled with physical fighting or when the opponent was considerably smaller in size. 4. When the same dyads were tested again several weeks later, but with the UV treatment reversed among opponents, none of the effects remained significant, but instead the winner was most likely to be the individual that won at their first encounter. 5. Our results suggest that structural‐based UV colouration can affect the outcome of an interaction, but that size differences and the outcome of initial interactions between opponents can override the influence of this signal in conflict resolution. Whether there is a functional basis to maintain a link between aggressiveness and colouration may thus be highly dependent on the general context under which individuals compete in the wild.
Hypermethylation of APC promoter 1A is associated with moderate activation of Wnt signalling pathway in a subset  of colorectal serrated adenomas
Authors: Fu Xiangsheng , Li Jing , Li Kang , Tian Xiaoxiao , Zhang Yali 
Published: November 2009

Aims:  The role of Wnt signalling pathway in serrated adenomas (SAs) remains to be identified. The aim of this study was to determine whether Wnt signalling plays a role in the pathogenesis of SAs, and to clarify the mechanism of Wnt signalling activation in SAs.Methods and results:  This study investigated immunoreactivities of adenomatous polyposis coli (APC) and β‐catenin, mutations of APC and β‐catenin genes, methylation status of APC promoter 1A in 12 SAs, and compared the findings with normal colorectal mucosa, hyperplastic polyps, traditional adenomas (TAs) and colorectal cancers (CRCs). APC expression was moderately decreased in SAs. Cytoplasmic accumulation of β‐catenin was demonstrated in 41.7% (5/12) of SAs, but membranous immunoreactivity of β‐catenin was lost in only 8.3% (1/12) of SAs. No β‐catenin mutation was detected in any of 12 SAs, and only one SA was found to be positive for APC gene mutation. Complete methylation of APC promoter 1A was found in 41.7% (5/12) of SAs, but in no TAs or CRCs.Conclusions:  Hypermethylation of APC promoter 1A, instead of mutations involving APC and β‐catenin, contributes to moderate activation of Wnt signalling in a subset of SAs.
Mucin extravasation in breast core biopsies – clinical significance and outcome correlation
Authors: Begum S M Khodeza Nahar , Jara‐Lazaro Ana Richelia , Thike Aye Aye , Tse Gary M‐K , Wong Jill S‐L , Ho Juliana T‐S , Tan Puay Hoon 
Published: November 2009

Aims:  To document the spectrum of lesions associated with mucin extravasation (ME) in breast core biopsy specimens, and to correlate with open surgical excisions.Methods and results:  Thirty‐nine lesions in 37 women with ME on core biopsies constituted the study group. Fibrocystic change (FC), atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS) were found in 21 (53.8%), 13 (33.3%) and four (10.3%) core biopsy specimens, respectively, with one (2.6%) consisting only of mucin pools. Except for the latter, all disclosed mucocoele‐like lesions (MLL) accompanying ME. Columnar cell lesions (CCL) were frequently observed (84.6%). On open biopsy, three cases underdiagnosed on core biopsy included FC that later disclosed ADH; one ADH lesion on core later upgraded to DCIS; and a case of mucin pools that revealed mucinous carcinoma on excision. The extent of CCL on core biopsy appeared to predict sinister lesions on open excision. For calcified lesions that were completely removed on core biopsy, there were no malignant lesions discovered on open excision that had not already been diagnosed preoperatively.Conclusions:  ME and MLL on core biopsy warrant close radiological–pathological correlation. When the entire radiological abnormality has been removed with large core mammotome biopsy specimens, surgery may potentially be avoided in histologically benign lesions, although such an approach requires further validation.
Clinicopathological study of a series of 92 adrenocortical carcinomas: from a proposal of simplified diagnostic algorithm to prognostic stratification
Authors: Volante Marco , Bollito Enrico , Sperone Paola , Tavaglione Veronica , Daffara Fulvia , Porpiglia Francesco , Terzolo Massimo , Berruti Alfredo , Papotti Mauro 
Published: November 2009

Aims:  Pathological diagnosis of adrenocortical carcinoma relies on several microscopic features commonly used in combination in different scoring systems that are sometimes subjective and/or time consuming. The aim was to investigate the impact of individual pathological parameters in the diagnosis and prognosis of adrenocortical carcinoma.Methods and results:  The series included 92 malignant cases and a control series of 47 adenomas, all classified according to Weiss score criteria. The presence of disruption of the reticular network, as highlighted by histochemical staining, was present in all adrenocortical carcinomas and the inclusion of at least one of the three following additional parameters – mitotic index >5/50 high‐power fields (HPF), presence of necrosis and presence of vascular invasion – gave an algorithm with 100% sensitivity and specificity to recognize malignant tumours according to the Weiss system, with easier and more practical applicability. Moreover, on multivariate analysis, stage III/IV and mitotic count >9/50 HPF showed a strong adverse impact on disease‐free and overall survival, leading to the identification of three risk groups affected by a significantly different prognosis.Conclusions:  We have defined an easy‐to‐perform and highly specific and sensitive algorithm for the diagnosis and prognostic categorization of adrenocortical tumours.