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https://www.readbyqxmd.com/read/28213796/the-manchester-repair-an-instructional-video
#1
Caroline E Walsh, Lin L Ow, N Rajamaheswari, Peter L Dwyer
OBJECTIVE: The Manchester repair, developed in the UK by Donald, described in 1908, and later modified by Fothergill, is a well-studied and proven surgical treatment for uterovaginal prolapse when uterine preservation is desired. This operation is currently not widely performed in parts of the world (USA) but is becoming increasing popular in Europe. The objective of this video is to demonstrate our surgical technique and recommendations for successful completion of the procedure. METHODS: This patient is a 39-year-old woman with two previous vaginal deliveries who presented with a 1-year history of vaginal protrusion...
February 17, 2017: International Urogynecology Journal
https://www.readbyqxmd.com/read/28213753/electrophysiologic-studies-on-the-risks-and-potential-mechanism-underlying-the-proarrhythmic-nature-of-azithromycin
#2
Mengdan Zhang, Ming Xie, Sha Li, Ying Gao, Shuyin Xue, Huili Huang, Kesu Chen, Fuming Liu, Long Chen
The mechanisms underlying arrhythmia induced by the clinical use of azithromycin are poorly understood. We aimed to investigate the proarrhythmic effects of azithromycin using electrocardiogram (ECG) and ion channel models. In vivo and in vitro guinea pig ECG and current and voltage clamp recordings were carried out. Azithromycin at 114.6 mg/kg (three times the clinically relevant dose) reduced heart rate (HR) and prolonged the PR, QRS and rate-corrected QT (QTc) intervals of guinea pig ECG in vivo. In vitro technique revealed that azithromycin at 207...
February 17, 2017: Cardiovascular Toxicology
https://www.readbyqxmd.com/read/28213290/zd0947-a-sulphonylurea-receptor-modulator-detects-functional-sulphonylurea-receptor-subunits-in-murine-vascular-smooth-muscle-atp-sensitive-k-channels
#3
Tadashi Yamamoto, Kohei Takahara, Keiichiro Uchida, Noriyoshi Teramoto
In order to identify functional sulphonylurea receptor (SUR.x) subunits of native ATP-sensitive K(+) channels (KATP channels) in mouse portal vein, the effects of ZD0947, a SUR.x modulator, were investigated on spontaneous portal vein contractions, macroscopic membrane currents and unitary currents recorded (using patch-clamp techniques) in freshly dispersed mouse portal vein myocytes. Spontaneous contractions in mouse portal vein were reversibly reduced by ZD0947 in a concentration-dependent manner (Ki = 293nM)...
February 14, 2017: European Journal of Pharmacology
https://www.readbyqxmd.com/read/28210214/arginine-vasopressin-alters-both-spontaneous-and-phase-locked-synaptic-inputs-to-airway-vagal-preganglionic-neuron-via-activation-of-v1a-receptor-insights-into-stress-related-airway-vagal-excitation
#4
Xianxia Yan, Xingxin Chen, Yuhong Guo, Ding He, Yonghua Chen, Chunmei Xia, Jijiang Wang
The airway vagal preganglionic neurons (AVPNs) in the external formation of the nucleus ambiguus (eNA) play a major role in the vagal control of tracheobronchial smooth muscle tone and maintenance of airway resistance. The eNA receives vasopressinergic projection from the hypothalamic paraventricular nucleus (PVN), the key node for the genesis of psychological stress. Since airway vagal excitation is reportedly to be associated with the psychological stress-induced/exacerbated airway hyperresponsiveness in asthmatics, arginine vasopressin (AVP) might be involved in stress-related airway vagal excitation...
2017: Frontiers in Cellular Neuroscience
https://www.readbyqxmd.com/read/28205094/knockdown-of-cardiac-kir3-1-gene-with-sirna-can-improve-bradycardia-in-an-experimental-sinus-bradycardia-rat-model
#5
Yang Li, Xiaodan Fu, Zhi Zhang, Bo Yu
The objective of this study was to explore whether the inhibition of potassium inwardly rectifying channel (Kir3.1) with short interfering RNA (siRNA) can improve bradycardia in an experimental sinus bradycardia rat model. 54 Sprague Dawley (SD) rats were randomly divided into three groups: experimental group, control group, and sham group. Sinus bradycardia model was established in SD rats through chemical ablation of sinoatrial (SA) node with 20% formaldehyde. Variations of Kir3.1 expression at mRNA and protein level were examined with qPCR and Western blotting...
February 15, 2017: Molecular and Cellular Biochemistry
https://www.readbyqxmd.com/read/28205039/a-pooled-analysis-of-clinical-pharmacology-trials-investigating-the-pharmacokinetic-and-pharmacodynamic-characteristics-of-fast-acting-insulin-aspart-in-adults-with-type-1-diabetes
#6
Tim Heise, Thomas R Pieber, Thomas Danne, Lars Erichsen, Hanne Haahr
BACKGROUND: Fast-acting insulin aspart (faster aspart) is insulin aspart (IAsp) in a new formulation aiming to mimic the fast endogenous prandial insulin release more closely than currently available insulin products. In a post hoc analysis of pooled data from six clinical pharmacology trials, the pharmacological characteristics of faster aspart and IAsp were compared. METHODS: The analysis included 218 adult subjects with type 1 diabetes from six randomised, double-blind, crossover trials in the faster aspart clinical development programme...
February 15, 2017: Clinical Pharmacokinetics
https://www.readbyqxmd.com/read/28203415/changes-in-the-action-potential-and-transient-outward-potassium-current-in-cardiomyocytes-during-acute-cardiac-rejection-in-rats
#7
Wenqi Luo, Yixin Jia, Shuai Zheng, Yan Li, Jie Han, Xu Meng
BACKGROUND: Acute cardiac rejection contributes to the changes in the electrophysiological properties of grafted hearts. However, the electrophysiological changes of cardiomyocytes during acute cardiac rejection are still unknown. An understanding of the electrophysiological mechanisms of cardiomyocytes could improve the diagnosis and treatment of acute cardiac rejection. So it is important to characterize the changes in the action potential (AP) and the transient outward potassium current (Ito ) in cardiomyocytes during acute cardiac rejection...
January 2017: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/28202726/two-tonoplast-mate-proteins-function-as-turgor-regulating-chloride-channels-in-arabidopsis
#8
Haiwen Zhang, Fu-Geng Zhao, Ren-Jie Tang, Yuexuan Yu, Jiali Song, Yuan Wang, Legong Li, Sheng Luan
The central vacuole in a plant cell occupies the majority of the cellular volume and plays a key role in turgor regulation. The vacuolar membrane (tonoplast) contains a large number of transporters that mediate fluxes of solutes and water, thereby adjusting cell turgor in response to developmental and environmental signals. We report that two tonoplast Detoxification efflux carrier (DTX)/Multidrug and Toxic Compound Extrusion (MATE) transporters, DTX33 and DTX35, function as chloride channels essential for turgor regulation in Arabidopsis Ectopic expression of each transporter in Nicotiana benthamiana mesophyll cells elicited a large voltage-dependent inward chloride current across the tonoplast, showing that DTX33 and DTX35 each constitute a functional channel...
February 15, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28202629/improving-the-in-silico-assessment-of-proarrhythmia-risk-by-combining-herg-human-ether-%C3%A3-go-go-related-gene-channel-drug-binding-kinetics-and-multichannel-pharmacology
#9
Zhihua Li, Sara Dutta, Jiansong Sheng, Phu N Tran, Wendy Wu, Kelly Chang, Thembi Mdluli, David G Strauss, Thomas Colatsky
BACKGROUND: The current proarrhythmia safety testing paradigm, although highly efficient in preventing new torsadogenic drugs from entering the market, has important limitations that can restrict the development and use of valuable new therapeutics. The CiPA (Comprehensive in vitro Proarrhythmia Assay) proposes to overcome these limitations by evaluating drug effects on multiple cardiac ion channels in vitro and using these data in a predictive in silico model of the adult human ventricular myocyte...
February 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28202388/viral-vector-reprogramming-of-adult-resident-striatal-oligodendrocytes-into-functional-neurons
#10
Marc S Weinberg, Hugh E Criswell, Sara K Powell, Aadra P Bhatt, Thomas J McCown
Recent advances suggest that in vivo reprogramming of endogenous cell populations provides a viable alternative for neuron replacement. Astrocytes and oligodendrocyte precursor cells can be induced to transdifferentiate into neurons in the CNS, but, in these instances, reprogramming requires either transgenic mice or retroviral-mediated gene expression. We developed a microRNA (miRNA)-GFP construct that in vitro significantly reduced the expression of polypyrimidine tract-binding protein, and, subsequently, we packaged this construct in a novel oligodendrocyte preferring adeno-associated virus vector...
February 12, 2017: Molecular Therapy: the Journal of the American Society of Gene Therapy
https://www.readbyqxmd.com/read/28197715/vacuolar-ion-channels-in-the-liverwort-marchantia-polymorpha-influence-of-ion-channel-inhibitors
#11
Mateusz Koselski, Kazimierz Trebacz, Halina Dziubinska
Potassium-permeable slow activating vacuolar channels (SV) and chloride-permeable channels in the vacuole of the liverwort Marchantia polymorpha were characterized in respect to calcium dependence, selectivity, and pharmacology. The patch-clamp method was used in the study of ion channel activity in the vacuoles from the liverwort Marchantia polymorpha. The whole-vacuole recordings allowed simultaneous observation of two types of currents-predominant slow activated currents recorded at positive voltages and fast activated currents recorded at negative voltages...
February 14, 2017: Planta
https://www.readbyqxmd.com/read/28197552/altered-channel-conductance-states-and-gating-of-gabaa-receptors-by-a-pore-mutation-linked-to-dravet-syndrome
#12
Ciria C Hernandez, Weijing Kong, Ningning Hu, Yujia Zhang, Wangzhen Shen, Laurel Jackson, Xiaoyan Liu, Yuwu Jiang, Robert L Macdonald
We identified a de novo missense mutation, P302L, in the γ-aminobutyric acid type A (GABAA) receptor γ2 subunit gene GABRG2 in a patient with Dravet syndrome using targeted next-generation sequencing. The mutation was in the cytoplasmic portion of the transmembrane segment M2 of the γ2 subunit that faces the pore lumen. GABAA receptor α1 and β3 subunits were coexpressed with wild-type (wt) γ2L or mutant γ2L(P302L) subunits in HEK 293T cells and cultured mouse cortical neurons. We measured currents using whole-cell and single-channel patch clamp techniques, surface and total expression levels using surface biotinylation and Western blotting, and potential structural perturbations in mutant GABAA receptors using structural modeling...
January 2017: ENeuro
https://www.readbyqxmd.com/read/28197106/inhibition-of-intermediate-conductance-calcium-activated-k-channel-kca3-1-and-fibroblast-mitogenesis-by-%C3%AE-linolenic-acid-and-alterations-of-channel-expression-in-the-lysosomal-storage-disorders-fabry-disease-and-niemann-pick-c
#13
Aida Oliván-Viguera, Javier Lozano-Gerona, Laura López de Frutos, Jorge J Cebolla, Pilar Irún, Edgar Abarca-Lachen, Ana J García-Malinis, Ángel Luis García-Otín, Yolanda Gilaberte, Pilar Giraldo, Ralf Köhler
The calcium/calmodulin-gated KCa3.1 channel regulates normal and abnormal mitogenesis by controlling K(+)-efflux, cell volume, and membrane hyperpolarization-driven calcium-entry. Recent studies suggest modulation of KCa3.1 by omega-3 fatty acids as negative modulators and impaired KCa3.1 functions in the inherited lysosomal storage disorder (LSD), Fabry disease (FD). In the first part of present study, we characterize KCa3.1 in murine and human fibroblasts and test the impact of omega-3 fatty acids on fibroblast proliferation...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28197093/ultrastructural-and-functional-properties-of-a-giant-synapse-driving-the-piriform-cortex-to-mediodorsal-thalamus-projection
#14
Patric Pelzer, Heinz Horstmann, Thomas Kuner
Neocortico-thalamo-cortical loops represent a common, yet poorly understood, circuit employing giant synapses also referred to as "class I", giant, or driver synapses. Here, we characterize a giant synapse formed by projection neurons of the paleocortical piriform cortex (PIR) onto neurons of the mediodorsal thalamus (MD). Three-dimensional (3D) ultrastructure of labeled PIR-MD terminals, obtained by using serial-section scanning electron microscopy (EM) combined with photooxidation-based detection of labeled terminals, revealed a large terminal engulfing multiple postsynaptic dendritic excrescences...
2017: Frontiers in Synaptic Neuroscience
https://www.readbyqxmd.com/read/28196855/inactivation-of-girk-channels-weakens-the-pre-and-postsynaptic-inhibitory-activity-in-dorsal-raphe-neurons
#15
Nerea Llamosas, Luisa Ugedo, Maria Torrecilla
The serotonergic tone of the dorsal raphe (DR) is regulated by 5-HT1A receptors, which negatively control serotonergic activity via the activation of G protein-coupled inwardly rectifying K(+) (GIRK) channels. In addition, DR activity is modulated by local GABAergic transmission, which is believed to play a key role in the development of mood-related disorders. Here, we sought to characterize the role of GIRK2 subunit-containing channels on the basal electrophysiological properties of DR neurons and to investigate whether the presynaptic and postsynaptic activities of 5-HT1A, GABAB, and GABAA receptors are affected by Girk2 gene deletion...
February 2017: Physiological Reports
https://www.readbyqxmd.com/read/28195523/characteristics-of-implicit-sensorimotor-adaptation-revealed-by-task-irrelevant-clamped-feedback
#16
John Ryan Morehead, Jordan A Taylor, Darius Parvin, Richard B Ivry
Sensorimotor adaptation occurs when there is a discrepancy between the expected and actual sensory consequences of a movement. This learning can be precisely measured, but its source has been hard to pin down because standard adaptation tasks introduce two potential learning signals: task performance errors and sensory prediction errors. Here we employed a new method that induces sensory prediction errors without task performance errors. This method combines the use of clamped visual feedback that is angularly offset from the target and independent of the direction of motion, along with instructions to ignore this feedback while reaching to targets...
February 14, 2017: Journal of Cognitive Neuroscience
https://www.readbyqxmd.com/read/28193694/different-cav1-3-channel-isoforms-control-distinct-components-of-the-synaptic-vesicle-cycle-in-auditory-inner-hair-cells
#17
Philippe Fy Vincent, Yohan Bouleau, Gilles Charpentier, Alice Emptoz, Saaid Safieddine, Christine Petit, Didier Dulon
The mechanisms orchestrating transient and sustained exocytosis in auditory inner hair cells (IHCs) remain largely unknown. These exocytotic responses are believed to mobilize sequentially a readily releasable pool of vesicles (RRP) underneath the synaptic ribbons and a slowly releasable pool of vesicles (SRP) at farther distance from them. They are both governed by Cav1.3 channels and require otoferlin as Ca(2+) sensor but whether they use the same Cav1.3 isoforms is still unknown. Using whole cell patch clamp recordings in post-hearing mice, we show that only a proportion (∼25 %) of the total Ca(2+) current in IHCs, displaying fast inactivation and resistance to 20 μM nifedipine, a L-type Ca(2+) channel blocker, is sufficient to trigger RRP but not SRP exocytosis...
February 13, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28192964/collisions-of-ir-oxide-nanoparticles-with-carbon-nanopipettes-experiments-with-one-nanoparticle
#18
Min Zhou, Yun Yu, Keke Hu, Huolin L Xin, Michael V Mirkin
Investigating the collisions of individual metal nanoparticles (NPs) with electrodes can provide new insights into their electrocatalytic behavior, mass transport and interactions with surfaces. Here we report a new experimental setup for studying NP collisions based on the use of carbon nanopipettes to enable monitoring multiple collision events involving the same NP captured inside the pipette cavity. A patch clamp amplifier capable of measuring pA-range currents on the microsecond time scale with a very low noise and stable background was used to record the collision transients...
February 3, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28192441/cyclic-amp-regulates-postnatal-development-of-neural-and-behavioral-responses-to-nacl-in-rats
#19
Jie Qian, Shobha Mummalaneni, Tam-Hao T Phan, Gerard L Heck, John A DeSimone, David West, Sunila Mahavadi, Deanna Hojati, Karnam S Murthy, Mee-Ra Rhyu, Andrew I Spielman, Mehmet Hakan Özdener, Vijay Lyall
During postnatal development rats demonstrate an age-dependent increase in NaCl chorda tympani (CT) responses and the number of functional apical amiloride-sensitive epithelial Na+ channels (ENaCs) in salt sensing fungiform (FF) taste receptor cells (TRCs). Currently, the intracellular signals that regulate the postnatal development of salt taste have not been identified. We investigated the effect of cAMP, a downstream signal for arginine vasopressin (AVP) action, on the postnatal development of NaCl responses in 19-23 day old rats...
2017: PloS One
https://www.readbyqxmd.com/read/28192183/measuring-kinetics-and-potency-of-herg-block-for-cipa
#20
Monique J Windley, Najah Abi-Gerges, Bernard Fermini, Jules C Hancox, Jamie I Vandenberg, Adam P Hill
INTRODUCTION: The Comprehensive in vitro Proarrhythmic Assay (CiPA) aims to update current cardiac safety testing to better evaluate arrhythmic risk. A central theme of CiPA is the use of in silico approaches to risk prediction incorporating models of drug binding to hERG. To parameterize these models, accurate in vitro measurement of potency and kinetics of block is required. The Ion Channel Working Group was tasked with: i) selecting a protocol that could measure kinetics of block and was easily implementable on automated platforms for future rollout in industry and ii) acquiring a reference dataset using the standardized protocol...
February 10, 2017: Journal of Pharmacological and Toxicological Methods
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