bluuebunny/crossref_metadata_2025_split huggingface dataset:
Statistical tests for measures of colocalization in biological microscopy
Authors: MCDONALD JOHN H. , DUNN KENNETH W. 
Published: October 2013

SummaryColocalization analysis is the most common technique used for quantitative analysis of fluorescence microscopy images. Several metrics have been developed for measuring the colocalization of two probes, including Pearson's correlation coefficient (PCC) and Manders’ correlation coefficient (MCC). However, once measured, the meaning of these measurements can be unclear; interpreting PCC or MCC values requires the ability to evaluate the significance of a particular measurement, or the significance of the difference between two sets of measurements. In previous work, we showed how spatial autocorrelation confounds randomization techniques commonly used for statistical analysis of colocalization data. Here we use computer simulations of biological images to show that the Student's one‐sample t‐test can be used to test the significance of PCC or MCC measurements of colocalization, and the Student's two‐sample t‐test can be used to test the significance of the difference between measurements obtained under different experimental conditions.
Nicotine induces dendritic spine remodeling in cultured hippocampal neurons
Authors: Oda Akira , Yamagata Kanato , Nakagomi Saya , Uejima Hiroshi , Wiriyasermkul Pattama , Ohgaki Ryuichi , Nagamori Shushi , Kanai Yoshikatsu , Tanaka Hidekazu 
Published: October 2013

AbstractCholinergic neurons in the CNS are involved in synaptic plasticity and cognition. Both muscarinic and nicotinic acetylcholine receptors (nAChRs) influence plasticity and cognitive function. The mechanism underlying nAChR‐induced plasticity, however, has remained elusive. Here, we demonstrate morphological changes in dendritic spines following activation of α4β2* nAChRs, which are expressed on glutamatergic pre‐synaptic termini of cultured hippocampal neurons. Exposure of the neurons to nicotine resulted in a lateral enlargement of spine heads. This was abolished by dihydro‐β‐erythroidine, an antagonist of α4β2* nAChRs, but not by α‐bungarotoxin, an antagonist of α7 nAChRs. Tetanus toxin or a mixture of 2‐amino‐5‐phosphonovaleric acid and 6‐cyano‐7‐nitroquinoxaline‐2,3‐dione, antagonists of NMDA‐ and AMPA‐type glutamate receptors, blocked the nicotine‐induced spine remodeling. In addition, nicotine exerted full spine‐enlarging response in the post‐synaptic neuron whose β2 nAChR expression was knocked down. Finally, pre‐treatment with nicotine enhanced the Ca2+‐response of the neurons to glutamate. These data suggest that nicotine influences the activity of glutamatergic neurotransmission through the activation of pre‐synaptic α4β2 nAChRs, resulting in the modulation of spinal architecture and responsiveness. The present findings may represent one of the cellular mechanisms underlying cholinergic tuning of brain function.
image
Activation of nicotinic acetylcholine receptors (nAChRs) in brain influences plasticity and cognition. Here, activation of α4β2* nAChRs, which are expressed on glutamatergic presynaptic termini, results in the enlargement of dendritic spines through the modulation of the glutamatergic neurotransmission. The remodeled spinal architecture might be responsible for the change in responsiveness of neural circuitry, leading to cholinergic tuning of brain function.
Critical role of peripheral drug actions in experience‐dependent changes in nucleus accumbens glutamate release induced by intravenous cocaine
Authors: Wakabayashi Ken T. , Kiyatkin Eugene A. 
Published: October 2013

AbstractRecent studies reveal that cocaine experience results in persistent neuroadaptive changes within glutamate (Glu) synapses in brain areas associated with drug reward. However, it remains unclear whether cocaine affects Glu release in drug‐naive animals and how it is altered by drug experience. Using high‐speed amperometry with enzyme‐based and enzyme‐free biosensors in freely moving rats, we show that an initial intravenous cocaine injection at a low self‐administering dose (1 mg/kg) induces rapid, small and transient Glu release in the nucleus accumbens shell (NAc), which with subsequent injections rapidly becomes a much stronger, two‐component increase. Using cocaine‐methiodide, cocaine's analog that does not cross the blood–brain barrier, we confirm that the initial cocaine‐induced Glu release in theNAc has a peripheral neural origin. Unlike cocaine, Glu responses induced by cocaine‐methiodide rapidly habituate following repeated exposure. However, after cocaine experience this drug induces cocaine‐like Glu responses. Hence, the interoceptive actions of cocaine, which essentially precede its direct actions in the brain, play a critical role in experience‐dependent alterations in Glu release, cocaine‐induced neural sensitization and may contribute to cocaine addiction.imageUsing high‐speed amperometry with enzyme‐based biosensors in freely moving rats, we show that initial intravenous cocaine induces rapid, transient glutamate (Glu) release in the Nac (Nucleus accumbens), rapidly becoming a stronger, two‐component increase with subsequent injections. We show that the peripheral actions of cocaine, which precedes its direct central actions, play a critical role in experience‐dependent alterations in Glu release, possibly contributing to cocaine addiction.
Corticosterone targets distinct steps of synaptic transmission via concentration specific activation of mineralocorticoid and glucocorticoid receptors
Authors: Chatterjee Sreejata , Sikdar Sujit K. 
Published: October 2013

AbstractHippocampal neurons are affected by chronic stress and have a high density of cytoplasmic mineralocorticoid and glucocorticoid receptors (MR and GR). Detailed studies on the genomic effects of the stress hormone corticosterone at physiologically relevant concentrations on different steps in synaptic transmission are limited. In this study, we tried to delineate how activation of MR and GR by different concentrations of corticosterone affects synaptic transmission at various levels. The effect of 3‐h corticosterone (25, 50, and 100 nM) treatment on depolarization‐mediated calcium influx, vesicular release and properties of miniature excitatory post‐synaptic currents (mEPSCs) were studied in cultured hippocampal neurons. Activation of MR with 25 nM corticosterone treatment resulted in enhanced depolarization‐mediated calcium influx via a transcription‐dependent process and increased frequency of mEPSCs with larger amplitude. On the other hand, activation of GR upon 100 nM corticosterone treatment resulted in increase in the rate of vesicular release via the genomic actions of GR. Furthermore, GR activation led to significant increase in the frequency of mEPSCs with larger amplitude and faster decay. Our studies indicate that differential activation of the dual receptor system of MR and GR by corticosterone targets the steps in synaptic transmission differently.
image
The stress hormone corticosterone has multiple effects on neuronal physiology and function. In this study we show corticosterone differentially targets the steps of synaptic transmission depending on the genomic effects of its cognate receptors namely mineralocorticoid and glucocorticoid receptors (MR and GR), within its physiological range. Increasing concentrations of corticosterone enhanced synaptic transmission at distinct levels.
In vivo quantification of neuro‐glial metabolism and glial glutamate concentration using 1H‐[13C] MRS at 14.1T
Authors: Lanz Bernard , Xin Lijing , Millet Philippe , Gruetter Rolf 
Published: October 2013

AbstractAstrocytes have recently become a major center of interest in neurochemistry with the discoveries on their major role in brain energy metabolism. An interesting way to probe this glial contribution is given by in vivo 13C NMR spectroscopy coupled with the infusion labeled glial‐specific substrate, such as acetate. In this study, we infused alpha‐chloralose anesthetized rats with [2‐13C]acetate and followed the dynamics of the fractional enrichment (FE) in the positions C4 and C3 of glutamate and glutamine with high sensitivity, using 1H‐[13C] magnetic resonance spectroscopy (MRS) at 14.1T. Applying a two‐compartment mathematical model to the measured time courses yielded a glial tricarboxylic acid (TCA) cycle rate (Vg) of 0.27 ± 0.02 μmol/g/min and a glutamatergic neurotransmission rate (VNT) of 0.15 ± 0.01 μmol/g/min. Glial oxidative ATP metabolism thus accounts for 38% of total oxidative metabolism measured by NMR. Pyruvate carboxylase (VPC) was 0.09 ± 0.01 μmol/g/min, corresponding to 37% of the glial glutamine synthesis rate. The glial and neuronal transmitochondrial fluxes (Vxg and Vxn) were of the same order of magnitude as the respective TCA cycle fluxes. In addition, we estimated a glial glutamate pool size of 0.6 ± 0.1 μmol/g. The effect of spectral data quality on the fluxes estimates was analyzed by Monte Carlo simulations.
image
In this 13C‐acetate labeling study, we propose a refined two‐compartment analysis of brain energy metabolism based on 13C turnover curves of acetate, glutamate and glutamine measured with state of the art in vivo dynamic MRS at high magnetic field in rats, enabling a deeper understanding of the specific role of glial cells in brain oxidative metabolism. In addition, the robustness of the metabolic fluxes determination relative to MRS data quality was carefully studied.
Three‐dimensional moment arms and architecture of chimpanzee (Pan troglodytes) leg musculature
Authors: Holowka Nicholas B. , O'Neill Matthew C. 
Published: October 2013

AbstractThe muscular and skeletal morphology of the chimpanzee ankle and foot differs from that of humans in many important respects. However, little information is available on the moment arms and architecture of the muscles that function around chimpanzee ankle and foot joints. The main goals of this study were to determine the influence of changes in leg and foot position on the moment arms of these muscle–tendon units (MTUs), and provide new measurements of their architecture. Three‐dimensional moment arm data were collected from two adult, cadaveric Pan troglodytes specimens for 11 MTUs that cross the ankle and foot joints. Tendon‐excursion measurements were made throughout the full range of plantarflexion–dorsiflexion (PF–DF) and eversion–inversion (EV–IN), including repeated measurements for mm. gastrocnemius at 0 °, 45 °, 90 ° and 135 ° of knee flexion. The total range of motion was calculated from three‐dimensional joint motion data while ensuring that foot movement was restricted to a single plane. Measurements of muscle mass, fascicle length, pennation angle and physiological cross‐sectional area were then collected for each MTU. Our results demonstrate that joint position has a significant effect on moment arm lengths, and that in some cases this effect is counterintuitive. These new data contribute to filling a significant gap in previously published chimpanzee moment arm data, providing a comprehensive characterization of the MTUs that move the chimpanzee ankle and foot joints. They also provide empirical support to the notion that chimpanzees have larger ranges of motion at these joints than humans. Comparison of osteometric estimates of moment arm lengths to direct tendon‐excursion measures provides some guidance for the use of skeletal features in estimations of PF–DF moment arms. Finally, muscle architecture data are consistent with the findings of previous studies, and increase the sample size of the chimpanzee data that are currently available.
Immunolocalisation of fibrillin microfibrils in the calf metacarpal and vertebral growth plate
Authors: Yu Jing , Urban Jill 
Published: October 2013

AbstractOvergrowth of limbs and spinal deformities are typical clinical manifestations of Marfan syndrome (MFS) and congenital contractural arachnodactyly (CCA), caused by mutations of the genes encoding fibrillin‐1 (FBN1) and fibrillin‐2 (FBN2), respectively. FBN1 mutations are also associated with acromicric (AD) and geleophysic dysplasias (GD), and with Weill–Marchesani syndrome (WMS), which is characterised by short stature. The mechanisms leading to such abnormal skeletal growth and the involvement of the fibrillins are not understood. Postnatal longitudinal bone growth mainly occurs in the epiphyseal growth plate. Here we investigated the organisation of fibrillin microfibrils in the growth plate of the long bone and vertebra immunohistochemically. Fibrillin‐1 was dual‐immunostained with elastin, with fibrillin‐2 or with collagen X. We report that fibrillin microfibrils are distributed throughout all regions of the growth plate, and that fibrillin‐1 and fibrillin‐2 were differentially organised. Fibrillin‐1 was more abundant in the extracellular matrix of the resting and proliferative zones of the growth plate than in the hypertrophic zone. More fibrillin‐2 was found in the calcified region than in the other regions. No elastin fibres were observed in either the proliferative or hypertrophic zones. This study indicates that, as fibrillin microfibrils are involved in growth factor binding and may play a mechanical role, they could be directly involved in regulating bone growth. Hence, mutations of the fibrillins could affect their functional role in growth and lead to the growth disorders seen in patients with MFS, CCA, AD, GD and WMS.
‘Touching people in relationships’: a qualitative study of close relationships for people with an intellectual disability
Authors: Sullivan Faye , Bowden Keith , McKenzie Karen , Quayle Ethel 
Published: October 2013

Aims and objectivesTo explore the experiences and perceptions of close and sexual relationships of people with an intellectual disability.BackgroundPositive interpersonal relationships are beneficial for people with an intellectual disability, acting as a protective barrier against, social stigma and negative outcomes such as physical and mental health problems. The social networks of people with an intellectual disability are, however, often more restricted than those of the general population. There has been very little research exploring the views and experiences of people with an intellectual disability about social and sexual relationships.DesignExploratory study using a qualitative research design.MethodsSemi‐structured interviews were conducted with 10 (6 male, 4 female) participants. Data were analysed using interpretive phenomenological analysis.Results‘Touching other people in relationships’ was identified as a superordinate theme. The theme was represented by five subthemes: ‘Is wrong’; ‘Unsafe to talk about’; ‘Suggesting is safe’; ‘No freedom or fun’; and ‘Being touched’. The findings presented are drawn from a larger qualitative study.ConclusionsThe findings highlight the importance of touch and sexual behaviours in the close relationships of participants. Negative perceptions were observed to surround sexual behaviours. Rules and restrictions regarding physical contact were also described.Relevance to clinical practiceDisseminating these findings may increase awareness of the importance of physical contact in the close relationships of people with an intellectual disability and promote positive support arrangements.
Who Writes the News? Corporate Press Releases during Merger Negotiations
Authors: AHERN KENNETH R. , SOSYURA DENIS 
Published: October 2013

ABSTRACTFirms have an incentive to manage media coverage to influence their stock prices during important corporate events. Using comprehensive data on media coverage and merger negotiations, we find that bidders in stock mergers originate substantially more news stories after the start of merger negotiations, but before the public announcement. This strategy generates a short‐lived run‐up in bidders' stock prices during the period when the stock exchange ratio is determined, which substantially impacts the takeover price. Our results demonstrate that the timing and content of financial media coverage may be biased by firms seeking to manipulate their stock price.
Molecular investigation of menstrual tissue for the presence of Chlamydia trachomatis, Ureaplasma urealyticum and Mycoplasma hominis collected by women with a history of infertility
Authors: Michou I. Vassiliki , Constantoulakis Pantelis , Makarounis Kostantinos , Georgoulias Giorgos , Kapetanios Vassilis , Tsilivakos Vassilis 
Published: October 2013

AbstractAimAt present, routine laboratory investigation of the infectious agents implicated in female genital infections is mainly based on culture/direct fluorescence antibody (DFA) (immunofluorescence antibody test) results of cervicovaginal secretions. In this study the use of the menstrual tissue is introduced for the molecular detection of pathogens which are implicated in female infertility.Material and MethodsCervicovaginal secretions and menstrual tissue samples of 87 women (mean age 34.07 ± 5.17) experiencing infertility problems were screened for Chlamydia trachomatis, Ureaplasma urealyticum and Mycoplasma hominis presence using polymerase chain reaction (PCR, light cycler‐PCR). Cervicovaginal secretions were also tested by the culture/DFA technique. The results were compared using the binomial test.ResultsIn the overall study group, the prevalence of C. trachomatis was 25.3%, 18.3%, and 13.8%, the prevalence of U. urealyticum was 18.3%, 16.09% and 12.6% and the prevalence of M. hominis was 13.7%, 19.5% and 8.0% in the menstrual tissue, cervicovaginal secretions using PCR and cervicovaginal secretions culture/DFA, respectively. A statistically significant difference was revealed between the two methods for all three microbes and between menstrual tissue and cervicovaginal secretions PCR for chlamydia.ConclusionsThe use of menstrual tissue along with the PCR method seems to be an effective and thus novel alternative for the investigation of the infectious agents lying in the genital tract. One of the main advantages of this technique compared to cervicovaginal secretions is that it is non‐invasive and the sample can be collected at home, thus allowing the early detection and treatment of a condition that can otherwise lead to serious consequences, such as tubal obstruction, pelvic inflammatory disease, ectopic pregnancy, spontaneous abortions and unexplained infertility.
Expression of Concern: Novel modification of B‐Lynch uterine compression sutures for management of atonic postpartum hemorrhage: VV uterine compression sutures
Authors: El‐Refaeey Abdel‐Aziz , Gibreel Ahmed , Fawzy Muhammad 
Published: October 2013

AbstractAimThe aim of this study was to demonstrate a novel modification of uterine compression sutures for use in women with primary postpartum hemorrhage and to evaluate its effectiveness.Material and MethodsThis was a prospective observational study. Nineteen patients with atonic postpartum hemorrhage were subjected to the novel VV uterine compression sutures at the time of cesarean delivery.ResultsThe procedure was successful in 18 out of 19 women (94.7%) in controlling the bleeding and preserving the patient's uterus. Only one patient required supravaginal hysterectomy.ConclusionsVV compression sutures comprise an easy, safe and effective procedure that can be applied in cases of atonic postpartum hemorrhage.
Determinants of pelvic organ prolapse among the women of the western part of Nepal: A case–control study
Authors: Thapa Subash , Angdembe Mangesh , Chauhan Deepak , Joshi Ranjila 
Published: October 2013

AbstractAimThis study was carried out in order to identify the determinants of pelvic organ prolapse (POP) among the women of the western part of Nepal.MethodsThis was a matched case–control study. Cases were defined as women diagnosed with third and fourth degree POP, and the control group consisted of women who were screened and confirmed of not having any degree of POP. Cases (n = 183) and controls (n = 183) were randomly selected and for each case, one control was selected, matched by age and place of residence. A semistructured interview was carried out to obtain the information for both groups. Bivariate analysis along with conditional logistic regression analysis was carried out to identify the association between selected variables with POP.ResultsThe results showed the significant association between number of vaginal deliveries, tear of vagina in the last childbirth, sphincter damage in the last childbirth and duration of labor in the last childbirth with POP, after adjusting for educational status of the women, carrying heavy loads, type of usual work and incidence of diarrhea.ConclusionThe results suggest that prolonged labor along with vaginal delivery having sphincter and vaginal tear are the determinants of POP and program managers should strongly consider these factors to develop interventions targeting the prevention of POP.
Asymmetrical fetal growth is not associated with altered trophoblast apoptotic activity in idiopathic intrauterine growth retardation
Authors: Roje Damir , Zekic Tomas Sandra , Capkun Vesna , Marusic Jelena , Resic Jasminka , Kuzmic Prusac Ivana 
Published: October 2013

AbstractAimTo investigate whether there is difference in trophoblast apoptosis between infants with asymmetrical idiopathic intrauterine growth retardation (IUGR) and those with symmetrical fetal growth appropriate for gestational age (AGA).MethodsData and placentas from 52 singleton term pregnancies with idiopathic IUGR, from which a subgroup of 33 (63.4%) infants with asymmetrical growth and malnutrition was identified using the ponderal index served as a study group. The control group included 60 (86.9%) infants with symmetrical growth, identified by the same criterion among 69 normal singleton pregnancies with AGA. IUGR was defined by birthweight less than the 10th percentile of standard values. Ponderal index value was considered as the measurement of fetal growth proportionality.ResultsThe proportion of fetal thinness up to ponderal index value was greater in the IUGR group than control (χ2 = 9.2; P = 0.002). There was no statistically significant difference in the cytotrophoblast proliferation (t = 0.88; P = 0.373), trophoblast expression of the Bcl‐2 anti‐apoptotic factor (z = 0.66; P = 0.505), total trophoblast apoptotic index (t = 0.45; P = 0.651), as in cytotrophoblast (t = 0.01; P = 0.988) and syncytiotrophoblast apoptotic index (t = 0.34; P = 0.730) between the idiopathic asymmetrical IUGR and control group.ConclusionAsymmetry of fetal growth is a result of rather long‐term placental nutritive insufficiency in which trophoblasts have a central role. Although being crucial for its functioning, the proliferative and apoptotic trophoblast activity remains unaltered in the placentas from pregnancies with idiopathic IUGR and asymmetrical fetal growth. The results obtained in this study indicate that placental nutritive insufficiency may develop without any deviation in the physiological trophoblast regeneration via apoptosis.