Impact of xenotransplantation of multipotent mesenchymal stem cells of the bone marrow on the recovery of the structural organization and functional activity of the retina in its damage

Among the potential sources of cells for transplantation, the most promising autologous material for cell therapy and tissue engineering are multipotent mesenchymal stem cells (MMSC). The authors carried out an experiment dealing with MMSC xenotransplantation into the rabbit suprachoidal space on a model of laser retinal coagulation. For objective assessment of the magnitude and pattern of changes in the functional activity of different retinal cellular elements and the efficiency of MMSC transplantation, they performed electroretinographic and histological studies. The study indicated that MMSC transplantation into the suprachoroidal space is a safe and effective procedure for cell incorporation in order to treat retinal diseases. Electroretinography provided evidence that single MMSC transplantation better preserved the function of photoreceptors (a-wave). Histomorphometric studies demonstrated that the inserted cells stimulated reparative processes in the laser-induced damaged retina.     

Neuroophthalmic symptoms of multiple sclerosis

The significance of neuroophthalmological symptoms in the diagnosis of disseminated sclerosis are analyzed. Fifty-two patients presented with the optic form of the disease of different severity. Subclinical stage of contralateral involvement was detected in patients with unilateral retrobulbar neuritis, which indicated dissemination of the process. Diseases of optic and oculomotor nerves of unknown etiology in young subjects can be an early symptom of disseminated sclerosis. The frequency of ocular and oculomotor disorders in disseminated sclerosis dictates regular neuroophthalmological examinations of patients with suspected disseminated sclerosis for early detection of the disease, which is particularly important for prediction of its course and outcome.     

Functional diagnosis of retinal ischemia. Communication 1. Reaction of Muller cells at early stages of diabetic retinopathy

Electroretinographic examinations were made in 191 patients with non-proliferative and pre-proliferative diabetic retinopathy. On the basis of the ratio of b-wave in ??? and ???? at 12 Hz, the glial index (Cg) was estimated for evaluating the functional changes in Muller cells. As the retinal ischemia aggravated, C@f was increasing, which was indicative of an activated metabolism of Muller cells. C@g was shown to be a sensitive criterion of retinal ischemia ensuring the detection of initial stages of retinal ischemia prior to the detection of changes recognizable in ophthalmoscopy and fluorescence angiography. The established regularities of changing functions in Muller glia and in glia-neuron ratios denote the possibility of using the electroretinographic criteria in the diagnosis of lesions in the retina and of early signs of retinal dystrophy in diabetic retinopathy.     

A dried aspen bark extract in the experimental therapy of gastric peptic ulcer

Dry aspen bark extract exhibits pronounced antiulcerogenic activity as demonstrated by the results of experiments using the models of histamine and atophan induced ulcers and the ulceration model according to H. Shay. The gastroprotector activity is manifested by decreasing number of animals with ulceration damage in the mucous membrane of the stomach and markedly decreasing ulcer density. The antiulcerogenic effect of the dry aspen bar extract is comparable to that of the reference drugs alanton and gastrozepin.     

Correction by common sea buckthorn bark and sprout extracts of hormonal and metabolic disturbances during stress in rats

Long-term administration of the common sea buckthorn bark and sprout extract improves the hormonal-metabolic organism status in rats disturbed by a stress factor (immobilization). The drug administration led to normalization of the altered functional activity indices of the neuro-endocrine system (disturbed adrenocorticotropin, 11-deoxycortisol, insulin, urea, and glucose levels) by affecting the production of glucocorticoids and increasing the hypothalamus sensitivity with respect to regulatory signals.     

Early changes in the bioelectrical activity of retina after eyeball contusion

Characteristic signs of changes in the bioelectrical activity of the retina soon after contusion of the eyeball supplement the functional criteria used for accurate diagnosis of the severity of contusion (classification of the injury). The most sensitive indicator of electroretinography is the amplitude of the electroretinogram (ERG) a-wave, which is sharply suppressed during the first three days in injury of any severity. Recovery of the bioelectrical activity of photoreceptors is delayed in comparison with the time course of the function of the second-order neurons (more rapid recovery of the b-wave in comparison with the a-wave). The reactivity of Müller cells increases in severe contusion, which is shown by a more pronounced decrease in the ERG b-wave amplitude and less expressed changes in low-frequency ERG. Analysis of the time course of biopotentials during repeated examinations of the patients helps control the efficacy of treatment. The results indicate that electroretinographic examinations are the most desirable 5-7 days after the contusion, because at this period the differences in the bioelectrical activity of the retina are the most expressed. The most informative parameters of electroretinography are the time course of total ERG a- and b-waves and the low-frequency rhythmic ERG.