from Genetics via xlomafota13 on Inoreader http://ift.tt/2fa0C6D
via IFTTT
Τετάρτη 23 Νοεμβρίου 2016
A novel RAD21 variant associated with intrafamilial phenotypic variation in Cornelia de Lange syndrome – review of the literature
In a patient with CdLS (IV.16) we identifed a novel single basepair deletion (c.704delG) in RAD21, which encodes a cohesin pathway protein. The variant is predicted to result in a premature stop codon [p.(Ser235Ilefs*19)] and hereby would have a deleterious effect. RAD21 variants have previously been described only in five cases with cohesinopathies (b). Notably, the deletion was found in the mother and the two aunts of the index patient, and none of them had been suspected of having CdLS or a cohesinopathy prior to this study (a). The index patient can be classified as mild CdLS, but the other family members do not fulfill the diagnostic criteria of CdLS. This study together with previous reports suggests incomplete penetrance associated with RAD21 variants and these individuals may therefore be underdiagnosed.
from Genetics via xlomafota13 on Inoreader http://ift.tt/2gizlv3
via IFTTT
Intraspinal microstimulation and diaphragm activation following cervical spinal cord injury
Intraspinal microstimulation (ISMS), using implanted electrodes, can evoke locomotor movements after spinal cord injury (SCI), but has not been explored in the context of respiratory motor output. An advantage over epidural and direct muscle stimulation is the potential of ISMS to selectively stimulate components of the spinal respiratory network. The present study tested the hypothesis that medullary respiratory activity could be used to trigger mid-cervical ISMS and diaphragm motor unit activation in rats with cervical SCI. Studies were conducted after acute (hours) and subacute (5-21 days) C2 hemisection (C2Hx) injury in adult rats. Inspiratory bursting in the genioglossus (tongue) muscle was used to trigger a 250 ms train stimulus (100 Hz, 100-200 µA) to the ventral C4 spinal cord, targeting the phrenic motor nucleus. After both acute and subacute injury, genioglossus EMG activity effectively triggered ISMS and activated diaphragm motor units during the inspiratory phase. The ISMS paradigm also evoked short-term potentiation of spontaneous inspiratory activity in the previously paralyzed hemidiaphragm (i.e., bursting persisting beyond the stimulus period) in approximately 70% of the C2Hx animals. We conclude that medullary inspiratory output can be used to trigger cervical ISMS and diaphragm activity after SCI. Further refinement of this method may enable "closed loop like" ISMS approaches to sustain ventilation after severe SCI.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2fqXzCq
via IFTTT
Neuronal Pattern Separation of Motion-Relevant Input in LIP Activity
In various regions of the brain, neurons discriminate sensory stimuli by decreasing the similarity between ambiguous input patterns. Here we examine whether this process of pattern separation may drive the rapid discrimination of visual motion stimuli in the lateral intraparietal area (LIP). Starting with a simple mean-rate population model that captures neuronal activity in LIP, we show that overlapping input patterns can be reformatted dynamically to give rise to separated patterns of neuronal activity. The population model predicts that a key ingredient of pattern separation is the presence of heterogeneity in the response of individual units. Furthermore, the model proposes that pattern separation relies upon heterogeneity in the temporal dynamics of neural activity and not merely in the mean firing rates of individual neurons over time. We confirm these predictions in recordings of macaque LIP neurons and show that the accuracy of pattern separation is a strong predictor of behavioral performance. Overall, results propose that LIP relies on neuronal pattern separation to facilitate decision-relevant discrimination of sensory stimuli.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2gjEeHB
via IFTTT
Maintenance of neuronal size gradient in MNTB requires sound-evoked activit
The medial nucleus of the trapezoid body (MNTB) is an important source of inhibition during the computation of sound location. It transmits fast and precisely timed action potentials at high frequencies; this requires an efficient calcium clearance mechanism, in which the plasma membrane calcium ATPase 2 (PMCA2) is a key component. Deafwaddler (dfw2J) mutant mice have a null mutation in PMCA2 causing deafness in homozygotes (dfw2J/dfw2J) and high frequency hearing loss in heterozygotes (+/dfw2J). Despite the deafness phenotype, no significant differences in MNTB volume or cell number were observed in dfw2J homozygous mutants, suggesting PMCA2 is not required for MNTB neuron survival. The MNTB tonotopic axis encodes high to low sound frequencies across the medial to lateral dimension. We discovered a cell size gradient along this axis: lateral neuronal somata are significantly larger than medially located somata. This size gradient is decreased in +/dfw2J and absent in dfw2J/dfw2J. The lack of acoustically driven input suggests that sound-evoked activity is required for maintenance of the cell size gradient. This hypothesis was corroborated by selective elimination of auditory hair cell activity using either hair cell elimination in Pou4f3 DTR mice or inner ear tetrodotoxin (TTX) treatment. The change in soma size was reversible and recovered within 7 days of TTX treatment, suggesting that regulation of the gradient is dependent on synaptic activity, and that these changes are plastic rather than permanent.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2fr9Vul
via IFTTT
Contextual Effects of Noise on Vocalization Encoding in Primary Auditory Cortex
Robust auditory perception plays a pivotal function for processing behaviorally relevant sounds, particularly with distractions from the environment. The neuronal coding enabling this ability, however, is still not well understood. In this study we recorded single-unit activity from the primary auditory cortex (A1) of awake marmoset monkeys (Callithrix jacchus) while delivering conspecific vocalizations degraded by two different background noises: broadband white noise and vocalization babble. Noise effects on neural representation of target vocalizations were quantified by measuring the responses' similarity to those elicited by natural vocalizations as a function of signal-to-noise ratio. A clustering approach was used to describe the range of response profiles by reducing the population responses to a summary of four response classes (robust, balanced, insensitive, and brittle) under both noise conditions. This clustering approach revealed that on average about two-thirds of the neurons change their response class when encountering different noises. Therefore, the distortion induced by one particular masking background in single-unit responses is not necessarily predictable from that induced by another, suggesting the low likelihood of a unique group of noise-invariant neurons across different background conditions in A1. Regarding noise influence on neural activities, the brittle response group showed addition of spiking activity both within and between phrases of vocalizations relative to clean vocalizations, while the other groups generally showed spiking activity suppression within phrases, and the alteration between phrases was noise-dependent. Overall, the variable single-unit responses yet consistent response types imply that primate A1 performs scene analysis through the collective activity of multiple neurons.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2gjAJkL
via IFTTT
Using noise to shape motor learning
Each of our movements is selected from any number of alternative movements. Some studies have shown evidence that the central nervous system (CNS) chooses to make the specific movements that are least affected by motor noise. Previous results that the CNS has the natural tendency to minimize the effects of noise make the direct prediction that if the relationship between movements and noise were to change, the specific movements people learn to make would also change in a predictable manner. Indeed, this has been shown for well-practiced movements such as reaching. Here, we artificially manipulated the relationship between movements and visuomotor noise by adding noise to a motor task in a novel redundant geometry such that there arose a single control policy that minimized the noise. This allowed us to see if, for a novel motor task, people could learn the specific control policy that minimized noise, or if they would need to employ other compensation strategies to overcome the added noise. As predicted, subjects were able to learn movements that were biased towards the specific ones that minimized the noise, suggesting not only that the CNS can learn to minimize the effects of noise in a novel motor task but also that using artificial visuomotor noise can be a useful tool for teaching people to make specific movements. Using noise as a teaching signal promises to be useful for rehabilitative therapies and movement training with human-machine interfaces.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2fqZCX1
via IFTTT
Variations in vibrissal geometry across the rat mystacial pad: base diameter, medulla, and taper
Many rodents tactually sense the world through active motions of their vibrissae (whiskers), which are regularly arranged in rows and columns (arcs) on the face. The present study quantifies several geometric parameters of rat whiskers that determine the tactile information acquired. Findings include: 1) A meta-analysis of seven studies shows that whisker base diameter varies with arc length, with a surprisingly strong dependence on the whisker's row position within the array. 2) The length of the whisker medulla varies linearly with whisker length, and the medulla's base diameter varies linearly with whisker base diameter. 3) Two parameters are required to characterize whisker "taper": radius ratio (base radius divided by tip radius) and radius slope (the difference between base and tip radius, divided by arc length). A meta-analysis of five studies shows that radius ratio exhibits large variability due to variations in tip radius, while radius slope varies systematically across the array. 4) To within the resolution of the present study, radius slope does not differ between the proximal and distal segments of the whisker, where "proximal" is defined by the presence of the medulla. 5) Radius slope of the medulla is offset by a constant value from radius slope of the proximal portion of the whisker. We conclude with equations for all geometric parameters as functions of row and column position. In a companion paper we discuss some implications of these geometric results for vibrissal-based tactile sensing.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2fTJIIy
via IFTTT
Estimating oxygen uptake and energy expenditure during treadmill walking by neural network analysis of easy-to-obtain inputs
The study of oxygen uptake (Vo2) dynamics during walking exercise transitions adds valuable information regarding fitness. However, direct Vo2 measurements are not practical for general population under realistic settings. Devices to measure Vo2 are associated with elevated cost, uncomfortable use of a mask, need of trained technicians, and impossibility of long-term data collection. The objective of this study was to predict the Vo2 dynamics from heart rate and inputs from the treadmill ergometer by a novel artificial neural network approach. To accomplish this, 10 healthy young participants performed one incremental and three moderate constant work rate treadmill walking exercises. The speed and grade used for the moderate-intensity protocol was related to 80% of the Vo2 response at the gas exchange threshold estimated during the incremental exercise. The measured Vo2 was used to train an artificial neural network to create an algorithm able to predict the Vo2 based on easy-to-obtain inputs. The dynamics of the Vo2 response during exercise transition were evaluated by exponential modeling. Within each participant, the predicted Vo2 was strongly correlated to the measured Vo2 ( = 0.97 ± 0.0) and presented a low bias (~0.2%), enabling the characterization of the Vo2 dynamics during treadmill walking exercise. The proposed algorithm could be incorporated into smart devices and fitness equipment, making them suitable for tracking changes in aerobic fitness and physical health beyond the infrequent monitoring of patients during clinical interventions and rehabilitation programs.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2gigWy7
via IFTTT
Effects of repetitive transcranial magnetic stimulation of upper airway muscles during sleep in obstructive sleep apnea patients
We tested the hypothesis that stimulating the genioglossus by repetitive transcranial magnetic stimulation (rTMS) during the ascendant portion of the inspiratory flow of airflow-limited breaths would sustain the recruitment of upper airway dilator muscles over time and improve airway dynamics without arousing obstructive sleep apnea (OSA) patients. In a cross-sectional design, nine OSA patients underwent a rTMS trial during stable non-rapid eye movement (NREM) sleep. Submental muscle motor threshold (SUB) and motor-evoked potential were evaluated during wakefulness and sleep. During NREM sleep, maximal inspiratory flow, inspiratory volume, inspiratory time, shifts of electroencephalogram frequency, and pulse rate variability were assessed under three different stimulation paradigms completed at 1.2 sleep SUB stimulation output: 1) 5Hz-08 (stimulation frequency: 5 Hz; duration of train stimulation: 0.8 s); 2) 25Hz-02 (stimulation frequency: 25 Hz; duration of train stimulation: 0.2 s); and 3) 25Hz-04 (stimulation frequency: 25 Hz; duration of train stimulation: 0.4 s). SUB increased during NREM sleep (wakefulness: 23.8 ± 6.1%; NREM: 26.8 ± 5.2%; = 0.001). Two distinct airflow patterns were observed in response to rTMS: with and without initial airflow drops, without other airflow variables change regardless the stimulation paradigm applied. Finally, rTMS-induced cortical and/or autonomic arousal were observed in 36, 26, and 35% of all delivered rTMS trains during 5Hz-08, 25Hz-02, and 25Hz-04 stimulation paradigms, respectively. In conclusion, rTMS does not provide any airflow improvement of flow-limited breaths as seen with nonrepetitive TMS of upper airway dilator muscles. However, rTMS trains were free of arousals in the majority of cases.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2f9D7e5
via IFTTT
Contribution of genetic factors to platinum-based chemotherapy sensitivity and prognosis of non-small cell lung cancer
Publication date: Available online 23 November 2016
Source:Mutation Research/Reviews in Mutation Research
Author(s): Cristina Pérez-Ramírez, Marisa Cañadas-Garre, Miguel Ángel Molina, Ana I. Robles, María José Faus-Dáder, Miguel Ángel Calleja-Hernández
Although platinum-based chemotherapy remains the standard treatment for advanced NSCLC patients, clinical outcomes are poor and most patients develop high-grade toxicities. Genetic factors, such as single nucleotide polymorphisms (SNPs) involved in platinum pharmacodynamics, metabolism and mechanism of action, may account for inter-individual differences shown in effectiveness and toxicity. Polymorphisms in genes involved in DNA repair and others such as PI3K/PTEN/AKT and TGF-β pathways have been demonstrated to be associated with response, survival and toxicity in advanced NSCLC patients treated with platinum-based chemotherapy. Other cellular processes, like DNA methylation and proliferation have been connected with clinical outcome for platinum-based chemotherapy regimens through folate metabolism and cytokine signaling.The influence of gene polymorphisms in the NER pathway on clinical outcome has been extensively investigated in advanced NSCLC patients treated with platinum-based chemotherapy but contradictory results have been reported. The most recent and thorough meta-analyses have failed to show an association between ERCC1 C118T/C8092A and ERCC5 rs1047768 polymorphisms and response to platinum based chemotherapy. However, other polymorphisms in ERCC2 (Lys751Gln and Asp312Asn) and ERCC5 (rs2094258 and rs2296147) and have been related with overall survival (OS) and progression-free survival (PFS), respectively. The Arg194Trp and Gln399Arg polymorphisms in XRCC1, have also been extensively investigated. Their effects seem to be dependent on ethnicity, and recent meta-analyses have confirmed an association with response in Asian but not in Caucasian patients. The influence on overall response rate (ORR) of the rs861539 polymorphism in XRCC3, part of (DSB) repair pathway, has also been confirmed in a meta-analysis.Finally, SNPs in genes coding proteins of the p53, PI3K, TGF-β, membrane transporters, gluthatione metabolism enzymes and cytokine pathways have been less extensively investigated. Some polymorphisms have been reported to be associated with toxicity or clinical outcome, but data generally come from a limited number of studies and need to be confirmed.
Graphical abstract
from Genetics via xlomafota13 on Inoreader http://ift.tt/2fTzrvT
via IFTTT
TERT promoter mutations in telomere biology
Publication date: Available online 23 November 2016
Source:Mutation Research/Reviews in Mutation Research
Author(s): Barbara Heidenreich, Rajiv Kumar
Telomere repeats at chromosomal ends, critical to genome integrity, are maintained through an elaborate network of proteins and pathways. Shelterin complex proteins shield telomeres from induction of DNA damage response to overcome end protection problem. A specialized ribonucleic protein, telomerase, maintains telomere homeostasis through repeat addition to counter intrinsic shortcomings of DNA replication that leads to gradual sequence shortening in successive mitoses. The biogenesis and recruitment of telomerase composed of telomerase reverse transcriptase (TERT) subunit and an RNA component, takes place through the intricate machinery that involves an elaborate number of molecules. The synthesis of telomeres remains a controlled and limited process. Inherited mutations in the molecules involved in the process directly or indirectly cause telomeropathies. Telomerase, while present in stem cells, is deactivated due to epigenetic silencing of the rate-limiting TERT upon differentiation in most of somatic cells with a few exceptions. However, in most of the cancer cells telomerase reactivation remains a ubiquitous process and constitutes one of the major hallmarks. Discovery of mutations within the core promoter of the TERT gene that create de novo binding sites for E-twenty-six (ETS) transcription factors provided a mechanism for cancer-specific telomerase reactivation. The TERT promoter mutations occur mainly in tumors from tissues with low rates of self-renewal. In melanoma, glioma, hepatocellular carcinoma, urothelial carcinoma and others, the promoter mutations have been shown to define subsets of patients with adverse disease outcomes, associate with increased transcription of TERT, telomerase reactivation and affect telomere length; in stem cells the mutations inhibit TERT silencing following differentiation into adult cells. The TERT promoter mutations cause an epigenetic switch on the mutant allele along with recruitment of pol II following the binding of GABPA/B1 complex that leads to mono-allelic expression. Thus, the TERT promoter mutations hold potential as biomarkers as well as future therapeutic targets.
from Genetics via xlomafota13 on Inoreader http://ift.tt/2ftGmvr
via IFTTT
Sex-based difference in Achilles peritendinous levels of matrix metalloproteinases and growth factors after acute resistance exercise
Several recent investigations have demonstrated that the ability of various tendons to alter structural and functional properties in response to exercise are muted in women when compared to men. We hypothesize that this disparity between men and women may be due to a reduced tendon production of key mediators of tendon extracellular matrix (ECM) remodeling in response to mechanical loading, e.g. exercise. Using microdialysis before and after an acute bout of resistance exercise, we evaluated Achilles peritendinous levels of insulin-like growth factor-1 (IGF-1) and interleukin-6 (IL-6), which have both been shown to increase tendon collagen synthesis. Additionally, the matrix remodeling enzymes matrix metalloproteinase-2 (MMP-2), MMP-9, and tissue inhibitor of metalloproteinase-1 (TIMP-1) were also evaluated. IGF-1 levels were elevated (p<0.05) to a similar extent in men and women after 3-hours of exercise but remained elevated at 4-hours in only women. IL-6 levels were ~4-fold greater after exercise in both men and women (p<0.05). MMP-2 levels increased to a similar extent (~2-3-fold) in men and women (p<0.05). In contrast, MMP-9 increased with exercise but only in men (p<0.05). Lastly, TIMP-1 levels also increased (p<0.05) with exercise in men and women but the increase was more prolonged in women. In conclusion, we observed modest sex-differences in tendon release of MMP-9, TIMP-1, and IGF-1 after acute resistance exercise. If such differences persist throughout a chronic exercise training, they may contribute to the reduced ability of women to adapt to exercise when compared to men.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2gnONqO
via IFTTT
The effect of alternate-day caloric restriction on the metabolic consequences of eight days' bed rest in healthy lean men: a randomized trial
Background: Physical activity and alternate-day fasting/caloric restriction may both ameliorate aspects of the metabolic syndrome, such as insulin resistance, visceral fat mass accumulation, and cognitive impairment, by overlapping mechanisms. Objective: To test the hypothesis that alternate-day caloric restriction (ADCR) with overall energy balance would reduce insulin resistance and accumulation of visceral fat, in addition to improving cognitive functions, after eight consecutive days in bed. Design: Healthy, lean men (n = 20) were randomized to 1) 8 days' bed rest with 3 daily iso-energetic meals (control group, n = 10); and 2) 8 days' bed rest with 25% of total energy requirements every other day and 175% of total energy requirements every other day (ADCR group). Oral glucose tolerance testing, DXA scans, magnetic resonance imaging of the abdomen and brain, VO2 max, and tests for cognitive function were performed before and after bed rest. In addition, daily fasting blood samples and 24 h glucose profiles by continuous glucose monitoring system were assessed during the 8 days bed rest period. Results: Bed rest induced insulin resistance, visceral fat accumulation, and worsening of mood. No positive effects emerged from ADCR on these negative health outcomes. Compared to the control group, ADCR was associated with improved and steadier glycemic control on fasting days, and higher glycemic fluctuation and indices of insulin resistance on overeating days. Conclusions: In contrast to our hypothesis, the metabolic impairment induced by eight days of bed rest was not counteracted by ADCR with overall energy balance.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2gCRMhY
via IFTTT
A mechanistic physicochemical model of carbon dioxide transport in blood
A number of mathematical models have been produced that, given the Pco2 and Po2 of blood, will calculate the total concentrations for CO2 and O2 in blood. However, all these models contain at least some empirical features, and thus do not represent all of the underlying physicochemical processes in an entirely mechanistic manner. The aim of this study was to develop a physicochemical model of CO2 carriage by the blood to determine whether our understanding of the physical chemistry of the major chemical components of blood together with their interactions is sufficiently strong to predict the physiological properties of CO2 carriage by whole blood. Standard values are used for the ionic composition of the blood, the plasma albumin concentration and the haemoglobin concentration. All Km values required for the model are taken from the literature. The distribution of bicarbonate, chloride and H+ ions across the red cell membrane follows that of a Gibbs-Donnan equilibrium. The system of equations that results is solved numerically using constraints for mass balance and electro-neutrality. The model reproduces the phenomena associated with CO2 carriage, including the magnitude of the Haldane effect, very well. The structural nature of the model allows various hypothetical scenarios to be explored. Here we examine the effects of: i) removing the ability of haemoglobin to form carbamino compounds; ii) allowing a degree of Cl– binding to deoxygenated haemoglobin; and iii) removing the chloride (Hamburger) shift. The insights gained could not have been obtained from empirical models.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2gnSaOF
via IFTTT
Aerobic exercise in humans mobilizes HSC in an intensity dependent manner
Hematopoietic stem and progenitor cells are necessary to maintain, repair, and reconstitute the hematopoietic blood cell system. Mobilization of these cells from bone marrow to blood can be greatly increased under certain conditions, one such being exercise. The purpose of this study was to identify the importance of exercise intensity in hematopoietic mobilization, to better understand the mobilization kinetics post exercise, and to determine if exercise is capable of mobilizing several specific populations of hematopoietic cells that have clinical relevance in a transplant setting. Healthy individuals were exercised on a cycle ergometer at 70% of their WRpeak until volitional fatigue and at 30% of their WRpeak work matched to the 70% WRpeak bout. Blood was collected prior to, immediately post, and 10, 30 and 60 minutes post exercise. Total blood cells, hematocrit, and mononuclear cells isolated by density gradient centrifugation were counted. Specific populations of hematopoietic stem cells were analyzed by flow cytometry. Mononuclear cells, CD34+, CD34+/CD38-, CD34+/CD110+, CD3-/CD16+/CD56+, CD11c+/CD123-, and CD11c-/CD123+ cells per mL of blood increased post exercise. Overall, the 70% WRpeak exercise group showed greater mobilization immediately post exercise, while there was no observable increase in mobilization in the work matched 30% WRpeak exercise group. Mobilization of specific populations of hematopoietic cells mirrored changes in the general mobilization of mononuclear cells, suggesting that exercise serves as a non-specific mobilization stimulus. Evidently, higher intensity exercise is capable of mobilizing hematopoietic cells to a large extent and immediately post exercise is an ideal timepoint for their collection.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2gD3Yze
via IFTTT
Restoration of thermoregulation after exercise
Performing exercise, especially in the hot conditions, can heat the body causing significant increases in internal body temperature. To offset this increase, powerful and highly developed autonomic thermoregulatory responses (i.e., skin blood flow and sweating) are activated to enhance whole-body heat loss; a response mediated by temperature sensitive receptors in both the skin and the internal core regions of the body. Independent of thermal control of heat loss, nonthermal factors can have profound consequences on the body's ability to dissipate heat during exercise. These include the activation of the body's sensory receptors (i.e., baroreceptors, metaboreceptors, mechanoreceptors, etc.) as well as phenotypic factors such as age, sex, acclimation, fitness, and chronic diseases such as diabetes. The influence of these factors extend into recovery such that marked impairments in thermoregulatory function occur leading to prolonged and sustained elevations in body core temperature. Irrespective of the level of hyperthermia, there is a time-dependent suppression of the body's physiological ability to dissipate heat. This delay in the restoration of postexercise thermoregulation has been associated with disturbances in cardiovascular function which manifests most commonly as postexercise hypotension. This review examines the current knowledge regarding the restoration of thermoregulation postexercise. In addition, the factors that are thought to accelerate or delay the return of body core temperature to resting levels are highlighted with a particular emphasis on strategies to manage heat stress in athletic and/or occupational settings.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2gjm1dr
via IFTTT
Nutritional implications for ultra-endurance walking and running events
This paper examines the various nutritional challenges which athletes encounter in preparing for and participating in ultra-endurance walking and running events. Special attention is paid to energy level, perf...
from Physiology via xlomafota13 on Inoreader http://ift.tt/2fHF7pO
via IFTTT
Editorial board members
Source:Gene Expression Patterns, Volume 22, Issue 2
from Genetics via xlomafota13 on Inoreader http://ift.tt/2gCSD27
via IFTTT
False non-reactive VDRL in a patient with later syphilis and underlying HIV infection: A case report
2016-11-23T17-42-32Z
Source: Case Study and Case Report
Sonnes Fredson.
Sexually transmitted disease (STD) is still important public health problem around the world. Syphilis is an old disease that is still detectable in the present day. VDRL serological test is the classical laboratory investigation for syphilis. The problem of false reactive and false non-reactive VDRL is interesting finding. Here, the author reports a case of false non-reactive VRDL in a patient with later syphilis and underlying HIV infection.
from Scope via xlomafota13 on Inoreader http://ift.tt/2gnyYQM
via IFTTT
Preface to a special issue “Japanese national mapping projects on large-scale environmental monitoring and mapping in Fukushima volume 2”
Publication date: Available online 23 November 2016
Source:Journal of Environmental Radioactivity
Author(s): Kimiaki Saito, Yuichi Onda
from Radiology via xlomafota13 on Inoreader http://ift.tt/2fHeh16
via IFTTT
Editorial board
Publication date: December 2016
Source:Journal of Environmental Radioactivity, Volume 165
from Radiology via xlomafota13 on Inoreader http://ift.tt/2f8Har2
via IFTTT
Biosorption of U(VI) by modified Hottentot Fern: Kinetics and equilibrium studies
Publication date: Available online 23 November 2016
Source:Journal of Environmental Radioactivity
Author(s): Ke Zhou, Yaochi Liu, Zhaoguang Yang, Houzhi Liu
Batch experiments were conducted to investigate the biosorption of U(VI) onto Hottentot Fern (Cyclosorus interruptus). The selective adsorption, the adsorption of different sections of Cyclosorus interruptus (CI), and the adsorption of polluted CI compared with that of unpolluted one were studied in detail. The raw CI and the CI modified by CaCl2, MgCl2, MgCl2/H2O2 were investigated for adsorption of U(VI) from aqueous solution. The results indicate that raw CI showed good adsorption selectivity for U(VI), compared with the adsorption of Cu(II), Co(II) and Ni(II). The stem of CI possesses a prominent adsorption capacity compared to the leaf and root of CI, and the unpolluted CI showed its superiority in adsorption capacity than the polluted CI. Adsorption rate was very fast during the first 30 min in the whole adsorption process. The pseudo-second-order kinetics model was proposed for the adsorption of U(VI) and the equilibrium data fitted well to Langmuir adsorption isotherms. The maximum adsorption capacity of R-CI, Ca-CI, Mg-CI and Mg/H2O2-CI is 41.67, 52.63, 62.50 and 71.43 mg g−1 at 20 °C, respectively.
from Radiology via xlomafota13 on Inoreader http://ift.tt/2fHa7Xe
via IFTTT
Handling of recent plagiarism in JER
Publication date: December 2016
Source:Journal of Environmental Radioactivity, Volume 165
Author(s): S.C. (Steve) Sheppard
from Radiology via xlomafota13 on Inoreader http://ift.tt/2f8Omn3
via IFTTT
Activities and geochronology of 137Cs in lake sediments resulting from sediment resuspension
Publication date: Available online 23 November 2016
Source:Journal of Environmental Radioactivity
Author(s): Gerald Matisoff
In lakes with a large surface area to watershed ratio 137Cs delivery is primarily by direct atmospheric fallout to the lake surface, where its activity in the sediments has been used to estimate the exposure to organisms and sediment mass deposition rates. Comparison of 137Cs in the historical atmospheric fallout record with 137Cs activity profiles in sediment cores reveals that although the general features of a maxima in the fallout deposition can be matched to activity peaks in the core, the general shape of the 137Cs profile is not an exact replica of the fallout history. Instead, the sediment reflects post-depositional processes such as resuspension, bioturbation, partitioning of 137Cs between the sediment solids and the pore fluids, and molecular diffusion of 137Cs through the pore fluids. Presented here is a model that couples these processes to a system time averaging (STA) model that accounts for the time history of 137Cs fallout and the particle residence time in the water column or in the 'active' surface sediment subject to resuspension. Sediment profiles are examined by comparing reasonable ranges of each of the coefficients of each of these major processes and by applying the model to cores collected from two large, shallow lakes, Lake Erie (USA/Canada) and Lake Winnipeg (Canada). The results indicate that the STA model with molecular diffusion and sediment resuspension best describes the data from these large, shallow lakes.
Graphical abstract
from Radiology via xlomafota13 on Inoreader http://ift.tt/2fH7MeX
via IFTTT
Replica weapons: A collective effort to stop mistake of fact shootings
By Dave Blake, Force Certified Analyst, Certified Criminal Investigator
In September, police officers in Columbus, Ohio, were called to an armed robbery. They spotted people who fit the description of the robbers and pursued them on foot. When one suspect pulled a handgun from his waistband, he was immediately shot and killed by police. The handgun was discovered to be a replica BB gun with a laser sight and the suspect a 13-year-old boy.
There have been several cases around the country where children have been mistaken for armed suspects and lost their lives. In two similar incidents, one in October 2013 and another in November 2014, a 13- and a 12-year-old boy were also killed by police. Both boys were handling replica guns with the orange safety tips removed. These tragedies have devastated families and communities, as well as the officers who pulled the triggers.
The public is understandably quick to blame law enforcement for these "mistake of fact" shootings, incidents where an officer reasonably – but inaccurately – believed the suspect was armed and posed an imminent threat. In order to stop such incidents that involve replica weapons, we should consider if there is also a larger social problem at play.
Read the full story: Replica weapons: A collective effort to stop mistake of fact shootings
from EMS via xlomafota13 on Inoreader http://ift.tt/2g5hPuS
via IFTTT
Effect of silver nanoparticle on renal cell: a preliminary study
2016-11-23T16-31-07Z
Source: Advance Laboratory Medicine International
Alendra Alama, Corrosa Ponteno.
This is a report on in vitro testing on effect of silver nanoparticle on renal cell. According to this work, it revealed that after mixing the renal cell sediment with silver nanoparticle solution, the silver nanoparticle can be seen within the renal cells. In conclusion, the silver nanoparticle contains penetrating property into renal cell and this is the laboratory report on this observation implying for the possibility of nephrotoxicity due to the use of nanoparticle in the present nanomaterial era.
from Scope via xlomafota13 on Inoreader http://ift.tt/2giN5cF
via IFTTT
TMS combined with EEG in Genetic Generalized Epilepsy: A phase II diagnostic accuracy study
Epilepsy, the propensity for recurrent, unprovoked epileptic seizures, is one of the commonest serious neurological disorders. It is estimated that approximately 65 million people worldwide suffer from this disease, experiencing significant negative consequences on their physical and mental health, education, ability to work and their overall quality of life (Moshe et al, 2015).
from Physiology via xlomafota13 on Inoreader http://ift.tt/2f8EDwW
via IFTTT
Tissue Correlation of Nitrite in Plant Parts of Cassava (Manihot esculenta Crantz) and Nitrosamine Toxicity in Wistar Rat
2016-11-23T15-50-10Z
Source: Journal of Investigational Biochemistry
John Uyinmwen Bazuaye, Emmanuel Ndubisi Maduagwu, Babatunji Emmanuel Oyinloye.
Aim: This study was designed to determine the correlation in nitrite content of cassava (Manihot esculenta Crantz) as present in the various parts (roots, stems and leaves) and the possible hepatotoxicity when Wistar rats are exposed to N-nitosamine precursors. Methods: Cassava cultivar used for this experiment was collected from International Institute of Tropical Agriculture, Ibadan, Nigeria (IITA). Various parts (Roots, Stems and Leaves) was weighed and homogenized. The homogenate was filtered to get clear solution and nitrite content therein was analyzed. Thirty Wistar rats divided into three groups, classified into; Group 1, Group 2 and Group 3 were used for the in-vivo experiment. The urine nitrite content and serum biomarkers of toxicity namely; Serum alanine transaminase (ALT), aspartate transaminase (AST), alkalin phosphatase (ALP) and gamma-glutamyl transferase (GGT) was estimated and the histopathological changes in the liver was examined in order to evaluate the extent of toxicity. Results: The nitrite levels in the roots, stems and leaves of these cassava cultivars were estimated as follows: roots; 118±23.0 µg/50 g, stems; 14.4±17.7 µg/30 g and leaves; 112±30.4 µg/5 g. The nitrite correlations between the roots and leaves is r = 0.97, correlations between the roots and stems is r = 0.65 while the correlations between the stems and leaves is r = 0.63. Urinalysis test carried out shows urine is the major sources of excretion of N-nitrosamines from the system. Both Group 2 and Group 3 animals had a significant increase in ALT, AST, ALP and GGT levels in the serum. Histopathology study of liver is in agreement with these results. Conclusion: This study shows that there was a correlation in nitrite levels between the roots and leaves of cassava and the level of toxicity found in the liver of rat administer with N-nitrosamine precursors (DMA.HCL and NaNO₂).
from Scope via xlomafota13 on Inoreader http://ift.tt/2gCtipo
via IFTTT
Adult Complex Regional Pain Syndrome Type I: A Narrative Review
Complex regional pain syndrome type I (CRPS I) is a multifactorial painful disorder with a complex pathogenesis. Both peripheral and central mechanisms are involved. Acute CRPS I is considered an exaggerated inflammatory disorder but over time, because of altered function of the sympathetic nervous system, and maladaptive neuroplasticity, CRPS I evolves into a neurological disorder. This review thoroughly describes the pathophysiological aspects of CRPS I and summarizes the potential therapeutic options.
from Rehabilitation via xlomafota13 on Inoreader http://ift.tt/2fqhqBC
via IFTTT
Differential vascular reactivity responses acutely following ingestion of a nitrate rich red spinach extract
Abstract
Introduction
Inorganic nitrate ingestion has been posited to affect arterial blood pressure and vascular function.
Purpose
We sought to determine the acute effect of a red spinach extract (RSE) high in inorganic nitrate on vascular reactivity 1-h after ingestion in peripheral conduit and resistance arteries.
Methods
Fifteen (n = 15; males 8, females 7) apparently healthy subjects (aged 23.1 ± 3.3 years; BMI 27.2 ± 3.7 kg/m2) participated in this crossover design, double-blinded study. Subjects reported to the lab ≥2-h post-prandial and consumed RSE (1000 mg dose; ~90 mg nitrate) or placebo (PBO). Venipuncture was performed on three occasions: baseline, 30-min post-ingestion and between 65 to 75-min post-ingestion. Baseline vascular measurements [i.e., calf venous occlusion plethysmography, brachial artery flow-mediated dilation (FMD)], 30-min of continuous blood pressure (BP) and heart rate (HR) analysis, and follow-up vascular measurements beginning at 40-min post-ingestion were also performed.
Results
Humoral nitrate following RSE ingestion was significantly higher at 30- (+54 %; P = 0.039) and 65 to 75-min post-ingestion compared to baseline (+255 %, P < 0.001) and PBO at the same time points (P < 0.05). No significant changes in BP or HR occurred in either condition. Peak reactive hyperemia (RH) calf blood flow increased significantly (+13.7 %; P = 0.016) following RSE ingestion, whereas it decreased (−14.0 %; P = 0.008) following PBO ingestion. No significant differential FMD responses were detected (P > 0.05), though RH was decreased following the baseline measure in both conditions.
Conclusions
RSE significantly increased plasma nitrate 30-min post-ingestion, but acute microvascular (i.e., resistance vasculature) reactivity increases were isolated to the lower limb and no appreciable change in brachial artery FMD was observed.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2f8fS41
via IFTTT
Resistance-training exercises with different stability requirements: time course of task specificity
Abstract
Purpose
The aim of the study was to assess the task-specificity (greater improvements in trained compared to non-trained tasks), transferability and time-course adaptations of resistance-training programs with varying instability requirements.
Method
Thirty-six resistance-trained men were randomized to train chest press 2 days week−1 for 10 week (6 repetitions × 4 series) using a Swiss ball, Smith machine or dumbbells. A six-repetition maximum-strength test with the aforementioned exercises and traditional barbell chest press were performed by all participants at the first, 7th, 14th and final training session in addition to electromyographic activities of the prime movers measured during isometric bench press.
Results
The groups training with the unstable Swiss-ball and dumbbells, but not the stable Smith-machine, demonstrated task-specificity, which became apparent in the early phase and remained throughout the study. The improvements in the trained exercise tended to increase more with instability (dumbbells vs. Smith machine, p = 0.061). The group training with Smith machine had similar improvements in the non-trained exercises. Greater improvements were observed in the early phase of the strength-training program (first-7th session) for all groups in all three exercises, but most notably for the unstable exercises. No differences were observed between the groups or testing times for EMG activity.
Conclusion
These findings suggest that among resistance-trained individuals, the concept of task-specificity could be most relevant in resistance training with greater stability requirements, particularly due to rapid strength improvements for unstable resistance exercises.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2fq1vDz
via IFTTT
Effects of plantar stimulation on cardiovascular response to orthostatism
Abstract
Purpose
Walking is a complex locomotor process that involves both spinal cord reflexes and cortical integration of peripheral nerve input. Maintaining an upright body position requires not only neuromuscular activity but also cardiovascular regulation. We postulated that plantar mechanical stimulation might modulate autonomic nervous system activity and, thereby, impact blood pressure adaptation during standing.
Methods
Twelve healthy subjects underwent three randomly ordered 45-min 70°-saddle tilt tests while the plantar surfaces of the feet were stimulated using specially engineered Korvit boots in the following modes: (1) no stimulation, (2) disrupted stimulation, and (3) walking mode. Orthostatic tolerance time was measured for each trial. During testing, we obtained an electrocardiogram and measured blood pressure, skin blood flow, and popliteal vein cross-sectional area. We estimated central hemodynamics, baroreflex sensitivity and heart rate variability.
Results
Orthostatic tolerance time was not found to differ significantly between test conditions (37.2 ± 10.4, 40.9 ± 7.6, and 41.8 ± 8.2 min, for no stimulation, disrupted stimulation, and walking mode, respectively). No significant differences between treatment groups were observed for stroke volume or cardiac baroreflex sensitivity, both of which decreased significantly from baseline during tilt testing in all groups. Cardiac sympathetic index and popliteal vein cross-sectional area increased at the end of the tilt period in all groups, without significant differences between treatments.
Conclusions
Plantar mechanical stimulation is insufficient for immediate modulation of cardiac sympathetic and parasympathetic activity under orthostatic stress.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2f8gBC7
via IFTTT
Duration of fascicle shortening is affected by muscle architecture and sex
Abstract
Purpose
The purpose of this study was to examine muscle fascicle properties of the gastrocnemius medialis (GM) during contraction and stretch between males and females. During contraction muscle fascicles shorten and pennation angles increase to generate force. Due to the elastic nature of the attached tendon, the fascicles continue to shorten when maximal force is achieved in order to sustain isometric force and this duration of fascicle shortening (DFS) can be observed with ultrasonography. Linear and curved muscle fascicles both display these kinetics; however, it is currently unknown if static stretch prior to a maximal voluntary contraction (MVC) alters the DFS and whether the effect differs between males and females.
Methods
Subjects performed an isometric MVC of the plantar flexors before and after a 2-min maximal dorsi-flexion stretch. Plantar flexor force was measured and ultrasound videography used to record GM and Achilles tendon architecture.
Results
Males were stronger than females (p = 0.004). The DFS was longer for females compared to males (p = 0.001) and the addition of a static stretch increased the DFS for curved (p = 0.002), but not linear, fascicles. Curved fascicles were longer (p = 0.05) with larger pennation angles (p = 0.04) for both males and females when compared to linear fascicles. Tendon excursion was greater (p = 0.05) post-stretch during contraction when compared to pre-stretch.
Conclusions
This study provides evidence that regardless of sex, curved muscle fascicles behave differently than linear fascicles and should be considered separately when muscle architecture is examined.
from Physiology via xlomafota13 on Inoreader http://ift.tt/2f8gsPk
via IFTTT
Multi-center, double-blind, randomized, placebo-controlled, parallel-group study to evaluate the benefit of the probiotic Bifidobacterium infantis 35624 in non-patients with symptoms of abdominal discomfort and bloating
The American Journal of Gastroenterology
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2fo0fRa
via IFTTT
Lifestyle and Bowel Movements in School Children: results from the Toyama Birth Cohort Study
Pediatrics International
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2f5DRR6
via IFTTT
Long-Term Proton Pump Inhibitor Use Is Not Associated With Changes in Bone Strength and Structure
The American Journal of Gastroenterology
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2fnYAuO
via IFTTT
Single hospital visit day case laparoscopic hernia repair without prior outpatient consultation is safe and acceptable to patients
Surgical Endoscopy
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2f5yUb8
via IFTTT
Loss of KCNQ1 expression in stage II and stage III colon cancer is a strong prognostic factor for disease recurrence
British Journal of Cancer
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2fnYCCW
via IFTTT
Laparoscopic management of large hiatus hernia: Five-year cohort study and comparison of mesh-augmented versus standard crura repair
Surgical Endoscopy
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2f5xDB1
via IFTTT
Treatment-related hypertension as a pharmacodynamic biomarker for the efficacy of bevacizumab in advanced pancreas cancer: A pooled analysis of 4 prospective trials of gemcitabine-based therapy with bevacizumab
American Journal of Clinical Oncology
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2fnUTWc
via IFTTT
Long-term outcomes of sphincter-saving procedures for diffuse Crohn’s disease of the large bowel
Diseases of the Colon and Rectum
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2f5zx4G
via IFTTT
Phylogenetic analysis of full-length, early infection, hepatitis C virus genomes among people with intravenous drug use: The InC3 Study
Journal of Viral Hepatitis
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2fo0f3C
via IFTTT
Endoscopic ultrasound-guided fine needle aspiration of pancreatic lesions with 22 versus 25 Gauge needles: A meta-analysis
United European Gastroenterology Journal
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2f5zAgK
via IFTTT
Association between social support, functional status and change in Health Related Quality of Life and changes in anxiety and depression in colorectal cancer patients
Psycho-Oncology
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2fnUTpa
via IFTTT
Multi-target stool DNA test: Clinical performance and impact on yield and quality of colonoscopy for colorectal cancer screening
Gastrointestinal Endoscopy
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2f5ARo4
via IFTTT
A prominent role of Hepatitis D Virus in liver cancers documented in Central Africa
BMC Infectious Diseases
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2fnVuHp
via IFTTT
Twelve-year outcomes of laparoscopic adhesiolysis in patients with chronic abdominal pain: A randomized clinical trial
Surgery
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2f5B0bf
via IFTTT
Analysis of lesion localisation at colonoscopy: Outcomes from a multi-centre U.K. study
Surgical Endoscopy
from Gastroenterology via xlomafota13 on Inoreader http://ift.tt/2fnZQOs
via IFTTT
Cardiac surgery-associated acute kidney injury: much improved, but still long ways to go.
from Anaesthesiology via xlomafota13 on Inoreader http://ift.tt/2g2gCnS
via IFTTT
Εγγραφή σε:
Αναρτήσεις (Atom)