Determination of the time course of caloric nystagmus in patients with spinocerebellar degeneration using caloric step stimulus procedure

2017 ◽  
Vol 138 (1) ◽  
pp. 41-45
Author(s):  
Takamori Takeda ◽  
Ayane Makabe ◽  
Chiaki Hirai ◽  
Takeshi Tsutsumi
Keyword(s):  
Time Course ◽  
Spinocerebellar Degeneration ◽  
Caloric Nystagmus

Exosite-dependent regulation of factor VIIIa by activated protein C

Blood ◽  
2003 ◽  
Vol 101 (12) ◽  
pp. 4802-4807 ◽  
Author(s):  
Chandrashekhara Manithody ◽  
Philip J. Fay ◽  
Alireza R. Rezaie
Keyword(s):  
Protein C ◽  
Time Course ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Limited Proteolysis ◽  
Activated Protein C ◽  
Coagulation Cascade ◽  
Factor Va ◽  
Factor Viiia

AbstractActivated protein C (APC) is a natural anticoagulant serine protease in plasma that down-regulates the coagulation cascade by degrading cofactors Va and VIIIa by limited proteolysis. Recent results have indicated that basic residues of 2 surface loops known as the 39-loop (Lys37-Lys39) and the Ca2+-binding 70-80–loop (Arg74 and Arg75) are critical for the anticoagulant function of APC. Kinetics of factor Va degradation by APC mutants in purified systems have demonstrated that basic residues of these loops are involved in determination of the cleavage specificity of the Arg506 scissile bond on the A2 domain of factor Va. In this study, we characterized the properties of the same exosite mutants of APC with respect to their ability to interact with factor VIIIa. Time course of the factor VIIIa degradation by APC mutants suggested that the same basic residues of APC are also critical for recognition and degradation of factor VIIIa. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) of the factor VIIIa cleavage reactions revealed that these residues are involved in determination of the specificity of both A1 and A2 subunits in factor VIIIa, thus facilitating the cleavages of both Arg336 and Arg562 scissile bonds in the cofactor.

scholarly journals In Vitro Evaluation of the Sensitivity of a Hyaluronic Acid PEG Cross-Linked to Bovine Testes Hyaluronidase

2018 ◽  
Vol 6 (1) ◽  
pp. 20-24 ◽  
Author(s):  
Nicola Zerbinati ◽  
Torello Lotti ◽  
Damiano Monticelli ◽  
Virginia Martina ◽  
Giovanna Cipolla ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Soft Tissue ◽  
Chemical Reaction ◽  
Time Course ◽  
Soft Tissue Augmentation ◽  
Facial Soft Tissue ◽  
Microplate Reader ◽  
Kinetics Of

Neauvia Intense is biocompatible, injectable hyaluronic acid (HA) filler PEG cross-linked for facial soft-tissue augmentation that provides volume to tissues. The aim of the present study is to evaluate the sensitivity of Neauvia Intense in hyaluronidase from bovine testes in a time-course analysis. The test is based on the colourimetric determination of the N-acetyl – D - glucosamine (NAG) released by the hyaluronidase in standardised conditions. The in vitro conditions involve the treatment of Neauvia Intense with a known concentration of the enzyme (6080U/ml). The NAG content was determined at different times to assess the kinetics of the degradation (1h, 3h, 6h, 24h, 48h, 72h, 120h, and 168h); the Ehrlich’s reagent was used for the colourimetric quantification, by the method described by Reissing and colleagues. The intensity of the violet colour developed after the chemical reaction was proportional to the NAG present in each sample. A microplate reader at 585 nm read the absorbance. The amount of NAG released by the product was proportional to the time of incubation with bovine hyaluronidase, reaching a plateau after 168 hours.

Reactive Diffusion at the Cylindrical Dissolving of Copper in the Solder Melt

2011 ◽  
Vol 312-315 ◽  
pp. 387-392 ◽  
Author(s):  
Jaromír Drápala ◽  
Alena Struhařová ◽  
Daniel Petlák ◽  
Vlastimil Vodárek ◽  
Petr Kubíček
Keyword(s):  
Time Course ◽  
Solid Phase ◽  
Accurate Determination ◽  
Theoretical Description ◽  
Reactive Diffusion ◽  
Interface Boundary ◽  
Boundary Movement ◽  
Long Time ◽  
Melt Cooling

Problems of reactive diffusion at the solid phase and melt contact were studied theoretically and experimentally. The main intention was to calculate the time course of the solid phase dissolving in the case of cylindrical dissolving. These calculations were carried out on the assumption for the rate constant of dissolving K = const. In our work we give heed especially to the dominating process, which is the solid metal A dissolved in the melt B. During the dissolving the melt B saturates with the metal A and the process is influenced by convections which are characteristic for the given experimental configuration. A theoretical description of the kinetics of the solid phase dissolving in the melt will be presented for the case of cylindrical dissolving. The aim is to derive a relation for the interface boundary movement c(t) in dependence on time and a time course of growth of the element A concentration in the melt B. There are problems with accurate determination of the interface boundary movement after certain heating times of specimens, when it is observed experimentally, since intermetallic phases create in the original A metal at both the diffusion and cooling and some phases segregate at the solidifying melt cooling. The main intention was an experimental study of the copper dissolving in the tin melt. Experiments aimed to the determination of the Cu wires (diameters from 0.5 to 3.5 mm) dissolution in the solder melt were carried out at various selected temperatures and times. Rapid growth of phases in the metal A and determination of the thickness of layers with these phases pose considerable time demands to X-ray micro-analyses (WDX, EDX) of specimens after their long-time heating.

Time Course of Determination of Movement Direction in the Reaction Time Task in Humans

2001 ◽  
Vol 86 (3) ◽  
pp. 1195-1201 ◽  
Author(s):  
Martin Sommer ◽  
Joseph Classen ◽  
Leonardo G. Cohen ◽  
Mark Hallett
Keyword(s):  
Reaction Time ◽  
Motor Cortex ◽  
Time Course ◽  
Primary Motor Cortex ◽  
Cortical Excitability ◽  
Motor Evoked Potentials ◽  
Movement Direction ◽  
Movement Onset ◽  
Thumb Movement

The primary motor cortex produces motor commands that include encoding the direction of movement. Excitability of the motor cortex in the reaction time (RT) task can be assessed using transcranial magnetic stimulation (TMS). To elucidate the timing of the increase in cortical excitability and of the determination of movement direction before movement onset, we asked six right-handed, healthy subjects to either abduct or extend their right thumb after a go-signal indicated the appropriate direction. Between the go-signal and movement onset, single TMS pulses were delivered to the contralateral motor cortex. We recorded the direction of the TMS-induced thumb movement and the amplitude of motor-evoked potentials (MEPs) from the abductor pollicis brevis and extensor pollicis brevis muscles. Facilitation of MEPs from the prime mover, as early as 200 ms before the end of the reaction time, preceded facilitation of MEPs from the nonprime mover, and both preceded measurable directional change. Compared with a control condition in which no voluntary movement was required, the direction of the TMS-induced thumb movement started to change in the direction of the intended movement as early as 90 ms before the end of the RT, and maximum changes were seen shortly before the end of reaction time. Movement acceleration also increased with maxima shortly before the end of the RT. We conclude that in concentric movements a change of the movement direction encoded in the primary motor cortex occurs in the 200 ms prior to movement onset, which is as early as increased excitability itself can be detected.

A Validated Method for the Quality Control of Andrographis paniculata Preparations

Planta Medica ◽  
2017 ◽  
Vol 83 (14/15) ◽  
pp. 1207-1213 ◽  
Author(s):  
Anastasia Karioti ◽  
Patricia Timoteo ◽  
Maria Bergonzi ◽  
Anna Bilia
Keyword(s):  
Quality Control ◽  
Time Course ◽  
Symptomatic Treatment ◽  
Reversed Phase ◽  
Andrographis Paniculata ◽  
Gradient System ◽  
Solvent Mixtures ◽  
Relative Standard ◽  
Precision And Accuracy

Abstract Andrographis paniculata is a herbal drug of Asian traditional medicine largely employed for the treatment of several diseases. Recently, it has been introduced in Europe for the prophylactic and symptomatic treatment of common cold and as an ingredient of dietary supplements. The active principles are diterpenes with andrographolide as the main representative. In the present study, an analytical protocol was developed for the determination of the main constituents in the herb and preparations of A. paniculata. Three different extraction protocols (methanol extraction using a modified Soxhlet procedure, maceration under ultrasonication, and decoction) were tested. Ultrasonication achieved the highest content of analytes. HPLC conditions were optimized in terms of solvent mixtures, time course, and temperature. A reversed phase C18 column eluted with a gradient system consisting of acetonitrile and acidified water and including an isocratic step at 30 °C was used. The HPLC method was validated for linearity, limits of quantitation and detection, repeatability, precision, and accuracy. The overall method was validated for precision and accuracy over at least three different concentration levels. Relative standard deviation was less than 1.13%, whereas recovery was between 95.50% and 97.19%. The method also proved to be suitable for the determination of a large number of commercial samples and was proposed to the European Pharmacopoeia for the quality control of Andrographidis herba.

scholarly journals Single motoneuron succinate dehydrogenase activity.

1989 ◽  
Vol 37 (7) ◽  
pp. 1107-1114 ◽  
Author(s):  
G R Chalmers ◽  
V R Edgerton
Keyword(s):  
Enzymatic Activity ◽  
Succinate Dehydrogenase ◽  
Time Course ◽  
Processing System ◽  
Enzyme Reaction ◽  
Histochemical Assay ◽  
Computer Image Processing ◽  
Wide Range ◽  
Soma Size

We have developed a quantitative histochemical assay for measurement of succinate dehydrogenase (SDH) activity in single motoneurons. A computer image processing system was used to quantify the histochemical enzyme reaction product and to follow the time course of the reaction. The optimal concentration for each of the ingredients of the incubation medium for the SDH reaction was determined and the importance of using histochemical "blanks" in the determination of enzymatic activity was demonstrated. The enzymatic activity was linear with respect to reaction time and tissue thickness. The procedure described meets the criteria generally considered essential for establishment of a quantitative histochemical assay. The assay was then used to examine the SDH activity of cat and rat motoneurons. It was found that motoneurons with a small soma size had a wide range of SDH activity, whereas those with a large soma size were restricted to low SDH activity.

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