scholarly journals Development of a mafedine lyophilizate for parenteral use

2021 ◽  
Vol 10 (4) ◽  
pp. 88-94
Author(s):  
O. A. Terenteva ◽  
V. A. Vainshtein ◽  
V. V. Tikhonova ◽  
A. K. Whaley ◽  
M. A. Trofimov ◽  
...  

Introduction. Cerebrovascular disease (CVD) is the most important medical and social problem of modern neurology because they have the highest rates of morbidity, mortality and disablement in the population. The growing incidence of CVD as a result of an aging population worldwide requires the emergent development of therapeutics, diagnostic and preventive tools. However, the development of drugs for the treatment of brain diseases has limitations due to the presence of the blood-brain barrier, which protects the brain against most molecules from the bloodstream entering the central nervous system. At the St. Petersburg State Chemical Pharmaceutical University of the Ministry of Health of Russia the alpha-2 adrenergic agonist mafedine was synthesized, which has mild psychostimulant and anxiogenic effects and which may be used in the treatment of traumatic brain injury as a neuroprotective agent.Aim. The development of a dosage form of mafedine in order to improve its penetration into the central nervous system.Materials and methods. Mafedine (pharmaceutical substance) [6-oxo-1-phenyl-2-(phenylamino)-1,6-dihydropyrimidin-4-olate sodium] (St. Petersburg State Chemical-Pharmaceutical University of the Ministry of Health of Russia); lecithin, span-60, Tween-80, Poloxamer 188, mannitol, vitamin E, ascorbic acid, methylene chloride, dimethyl sulfoxide, acetonitrile, trifluoroacetic acid. The fine emulsion of mafedine was obtained by ultrasound. The dosage form of mafedine was obtained by freeze drying. Residual solvents were determined by gas chromatography. Quantitative analysis of mafedine was performed by high-performance liquid chromatography. Particle size and zeta potential of emulsion were determined on a Zetasizer Nano ZS.Results and discussion. Lyophilizate of mafedine was obtained and presenting as a light yellow porous, odorless tablet. The average mass of dry tablet was (0,17 ± 0,01) g with mafedine content is (26 ± 1) mg. The water content in the lyophilizate was 3,85 %. The quantity of methylene chloride in the lyophilizate correspond to the requirements for residual solvent content. The reconstitution time of lyophilizate into a primary emulsion was 3–5 seconds. The reconstituted dispersion was yellow, odorless, and did not break within 2 days during storage. The pH of the reconstituted emulsion was 7,34. The average particle size was (164,7 ± 6,4) nm, the zeta potential was –32 mV.Conclusion. The developed dosage form is stable according to its physicochemical and pharmaceutical characteristics and is suitable for experimental study on models as a neuroprotective and neurorehabilitation agent.

Author(s):  
Yuhei Hamada ◽  
Masashi Uchida ◽  
Sayaka Arai ◽  
Kaori Yamazaki ◽  
Mariko Takeda ◽  
...  

Abstract Background Generic drugs are heavily promoted in Japan. The aim of this retrospective single-center study was to clarify whether the frequency and reason that patients request a switch from a generic drug to the original drug differ according to therapeutic category and dosage form. Methods This study was performed at Chiba University Hospital. Prescription inquiries about 121 generic drugs from community pharmacies over a 3-year period (from July 2014 to June 2017) were analyzed. Results Approximately 30% of the requests were related to the efficacy, safety, and comfort of the generic drug. The most cited motive was “patient’s desire with no reason given” at 44.5%. According to multiple logistic regression analysis, therapeutic categories and dosage forms were associated with the requests. The median request frequency differed according to therapeutic category and dosage form. The frequency was highest for “agents affecting the central nervous system” and “tablets and capsules”, respectively. Among the therapeutic categories, “agents affecting the central nervous system” had the highest median number of requests related to “decreased effectiveness”; “cardiovascular agents” had the highest median number of requests related to “physician’s instruction”; and “agents for the epidermis” had the highest median number of requests related to “uncomfortable to use”. Among dosage forms, the odds ratio for patients’ original drug request for “liniment and patch” was about 1.5 times that for “tablets and capsules”. “Liniment and patch” had the highest median frequency of requests related to “decreased effectiveness”, “uncomfortable to use”, and “patient’s desire with no reason given”. Conclusions The request frequency and reason differed according to therapeutic category and dosage form. Pharmacists should advise each patient properly about the choice and switching of drug brands, taking into account the therapeutic category and dosage form, especially liniments and patches.


Author(s):  
Gladys Harrison

With the advent of the space age and the need to determine the requirements for a space cabin atmosphere, oxygen effects came into increased importance, even though these effects have been the subject of continuous research for many years. In fact, Priestly initiated oxygen research when in 1775 he published his results of isolating oxygen and described the effects of breathing it on himself and two mice, the only creatures to have had the “privilege” of breathing this “pure air”.Early studies had demonstrated the central nervous system effects at pressures above one atmosphere. Light microscopy revealed extensive damage to the lungs at one atmosphere. These changes which included perivascular and peribronchial edema, focal hemorrhage, rupture of the alveolar septa, and widespread edema, resulted in death of the animal in less than one week. The severity of the symptoms differed between species and was age dependent, with young animals being more resistant.


Author(s):  
John L.Beggs ◽  
John D. Waggener ◽  
Wanda Miller ◽  
Jane Watkins

Studies using mesenteric and ear chamber preparations have shown that interendothelial junctions provide the route for neutrophil emigration during inflammation. The term emigration refers to the passage of white blood cells across the endothelium from the vascular lumen. Although the precise pathway of transendo- thelial emigration in the central nervous system (CNS) has not been resolved, the presence of different physiological and morphological (tight junctions) properties of CNS endothelium may dictate alternate emigration pathways.To study neutrophil emigration in the CNS, we induced meningitis in guinea pigs by intracisternal injection of E. coli bacteria.In this model, leptomeningeal inflammation is well developed by 3 hr. After 3 1/2 hr, animals were sacrificed by arterial perfusion with 3% phosphate buffered glutaraldehyde. Tissues from brain and spinal cord were post-fixed in 1% osmium tetroxide, dehydrated in alcohols and propylene oxide, and embedded in Epon. Thin serial sections were cut with diamond knives and examined in a Philips 300 electron microscope.


Author(s):  
Ezzatollah Keyhani

Acetylcholinesterase (EC 3.1.1.7) (ACHE) has been localized at cholinergic junctions both in the central nervous system and at the periphery and it functions in neurotransmission. ACHE was also found in other tissues without involvement in neurotransmission, but exhibiting the common property of transporting water and ions. This communication describes intracellular ACHE in mammalian bone marrow and its secretion into the extracellular medium.


Author(s):  
S.S. Spicer ◽  
B.A. Schulte

Generation of monoclonal antibodies (MAbs) against tissue antigens has yielded several (VC1.1, HNK- 1, L2, 4F4 and anti-leu 7) which recognize the unique sugar epitope, glucuronyl 3-sulfate (Glc A3- SO4). In the central nervous system, these MAbs have demonstrated Glc A3-SO4 at the surface of neurons in the cerebral cortex, the cerebellum, the retina and other widespread regions of the brain.Here we describe the distribution of Glc A3-SO4 in the peripheral nervous system as determined by immunostaining with a MAb (VC 1.1) developed against antigen in the cat visual cortex. Outside the central nervous system, immunoreactivity was observed only in peripheral terminals of selected sensory nerves conducting transduction signals for touch, hearing, balance and taste. On the glassy membrane of the sinus hair in murine nasal skin, just deep to the ringwurt, VC 1.1 delineated an intensely stained, plaque-like area (Fig. 1). This previously unrecognized structure of the nasal vibrissae presumably serves as a tactile end organ and to our knowledge is not demonstrable by means other than its selective immunopositivity with VC1.1 and its appearance as a densely fibrillar area in H&E stained sections.


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