Search results for "Xylazine"
showing 8 items of 8 documents
Pressure-Stabilized Solvates of Xylazine Hydrochloride
2016
High pressure strongly favors the highest-density polymorph Z of active pharmaceutical ingredient 2-(2,6-xylidino)-5,6-dihydro-4H-1,3-thiazine hydrochloride (xylazine hydrochloride, XylHCl) up to about 0.1 GPa only, but still higher pressure destabilizes this structure. Above 0.1 GPa, XylHCl preferentially crystallizes as solvates with CH2Cl2, CHCl3, or (CH3)2CHOH depending on the solvent used. However, when XylHCl·H2O is dissolved in any of these solvents, the high-pressure crystallizations yield the hydrate XylHCl·H2O only. The single crystals of the CH2Cl2, CHCl3, and (CH3)2CHOH solvates could be grown in situ in a diamond anvil cell, which allowed their structure determination from the …
Anesthetic efficacy of ketamine-diazepam, ketamine-xylazine, and ketamine-acepromazine in Caspian Pond turtles (
2017
Objectives: The objective of this study was to assess the efficacy of different anesthetic drug combinations on the Caspian Pond turtles (Mauremys caspica). Subjects and Methods: Three groups of the Caspian Pond turtles (n = 6) were anesthetized with three different drug combinations. Initially, a pilot study was conducted to determine the best drug doses for the anesthetization of the turtles, and according to these results, ketamine–diazepam (120 mg/kg ketamine hydrochloride [5%] and 2 mg/kg diazepam [5%]), ketamine–acepromazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg acepromazine [1%]), and ketamine–xylazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg xylazine [2%]) wer…
Anesthetic efficacy of ketamine-diazepam, ketamine-xylazine, and ketamine-acepromazine in Caspian Pond turtles (Mauremys caspica)
2017
Objectives: The objective of this study was to assess the efficacy of different anesthetic drug combinations on the Caspian Pond turtles (Mauremys caspica). Subjects and Methods: Three groups of the Caspian Pond turtles (n = 6) were anesthetized with three different drug combinations. Initially, a pilot study was conducted to determine the best drug doses for the anesthetization of the turtles, and according to these results, ketamine-diazepam (120 mg/kg ketamine hydrochloride [5%] and 2 mg/kg diazepam [5%]), ketamine-acepromazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg acepromazine [1%]), and ketamine-xylazine (120 mg/kg ketamine hydrochloride [5%] and 1 mg/kg xylazine [2%]) wer…
Investigation of the phase transitions occurring during and after the dehydration of xylazine hydrochloride monohydrate.
2014
This paper reports an investigation of a complex solid state phase transition where two inter-converting polymorphs (X and A) of the pharmaceutical molecule xylazine hydrochloride formed and transformed during and after the dehydration of its monohydrate (H). The crystal structures of all three forms were compared. During the investigation of this solid state phase transition it was determined that the dehydration of H produced either a pure X form, or a mixture of the X and A forms. The phase composition depended on the sample preparation procedure and the experimental conditions. It was found that grinding of the hydrate enhanced the formation of polymorph X as a product of dehydration, w…
Continuous Theta-Burst Stimulation Intensity Dependently Facilitates Motor-Evoked Potentials Following Focal Electrical Stimulation of the Rat Motor …
2020
Although theta-burst stimulation (TBS) is known to differentially modify motor cortical excitability according to stimulus conditions in humans, whether similar effects can be seen in animals, in particular rats, remains to be defined. Given the importance of experimental rat models for humans, this study explored this stimulation paradigm in rats. Specifically, this study aimed to explore corticospinal excitability after TBS in anesthetized animals to confirm its comparability with human results. Both inhibition-facilitation configurations using paired electrical stimulation protocols and the effects of the TBS paradigm on motor-evoked potentials (MEPs) in rat descending motor pathways wer…
The effect of excipients on the stability and phase transition rate of xylazine hydrochloride and zopiclone
2015
The compatibility of thermodynamically unstable polymorph of two active pharmaceutical compounds (xylazine hydrochloride form X and zopiclone form C) with different excipients was investigated. The effects of the excipient and its amount in the sample on the thermal properties and possible chemical interactions were studied. The most commonly used excipients in the pharmaceutical industry - calcium carbonate, lactose hydrate, cellulose, magnesium stearate hydrate and calcium stearate hydrate were selected for this study. The dependence of the phase transition rate from an unstable to a more stable polymorph on the excipients and their amounts in the initial sample was analysed at 80°C, and …
Hydration and dehydration kinetics of xylazine hydrochloride
2009
From the experiments where mixture of xylazine hydrochloride hydrate H and anhydrous X were held at constant conditions, the stable form of xylazine hydrochloride can be found out. To determine equilibrium relative humidity, the unstable form of xylazine hydrochloride was inserted in thermostated humidity chamber and its weight was recorded by weighing the sample outside the chamber. The kinetic model and the rate constant for each condition were determined. The rate constants give information regarding the speed of the process at every experimentally used relative humidity. Thus using the data in coordinates k – p for each temperature it is possible to determine the water vapor pressure of…
The relative stability of xylazine hydrochloride polymorphous forms
2009
All four known xylazine hydrochloride polymorphous forms were obtained and their relative stabilities were compared directly at three different temperatures. At higher temperatures, it is possible to determine the relative stability of all forms directly by measuring the changes in the composition of the mixtures of two polymorphous forms using powder x-ray diffraction methods. At lower temperatures, a solvent was added to the mixture and the changes in composition were determined. Polymorph transition temperatures were determined directly. To predict the transition temperature which was not found using the direct method, the polymorph melting data and determined transition temperatures wer…