The Pattern of Granuloma Formation in the Liver of Rats as a Reflection of the Mechanism of Internalization of Submicron Silicon Particles

A morphological analysis of the liver of Wistar rats was performed 2 months after a single intravenous injection of porous silicon particles of different sizes (60-80, 250-300, and 500-600 nm; 2 mg/ml, 1 ml). Histological, immunohistochemical, and electron microscopic methods showed the development of CD68+ granulomas in all experimental groups. Injection of 60-80-nm porous silicon particles led to the formation of single large granulomas (>2000 μm2), while 500-600-nm nanoparticles caused the formation of numerous smaller granulomas. The mechanism of involution of granulomas by apoptosis of Kupffer cells and the absence of subsequent connective tissue remodeling of the organ tissue is shown.

[The most privy of all privy councilors in the Russian Empire: To the biography of Vyacheslav Avksentievich Manassein (1841-1901)]

The article, on the basis of archival documents introduced into scientific circulation, considers personality of prominent Russian physician Vyacheslav Avksentievich Manassein (1841-1901), who held the position of professor of the therapeutic Chairs of the Medical Surgical Academy in 1875-1892. The Manassein's public activity had special character, reaching All-Russian scale owing to the weekly "The Physician" published by him in 1880-1901. The article considers various aspects related to the scientific school of S. P. Botkin. For the first time, it is reported about the facts shedding light on complicated relationship of S. P. Botkin with his student V. A. Manassein.

[«Our whole family does not get out of the common cold»: an ear, throat and nose disease in the conditions of S.P. Botkin]

The article presents an epistolary insight into the history of otorhinolaringology in Russia. It shows pathology of ear, nose and throat, which S.P. Botkin faced: cases of diseases of empress Maria Aleksandrovna, grand duke Vyacheslav Konstantinovich, poet N.A. Nekrasov, publisher A.A. Kraevsky, Sergey Petrovich himself, his relatives and loved ones. The biographical singularity of the famous doctor's patients is noted. On the materials of family letters of 1855-1889 yrs., service diaries of 1872-1889 yrs. and S.P. Botkin's clinical lectures it is shown how daily cases and casuistry of otorhinolaryngology pathology formed scientific innovative ideas.

"The letters of S. P. Botkin from Bulgaria. 1887": The return of the manuscript in Russia

The previous report partially brought to light history of publishing of "The letters of S. P. Botkin from Bulgaria 1877". The original letters were abroad for many years and they were returned to the USSR in 1974 by grandchildren of S. P. Botkin, S. P. Chekhov and D. P. Chekhov, who resided in France. The circumstances of handing over of the letters to the N. A. Semashko Institute of Health Organization and Social Hygiene are presented. The letters have not been republished for 130 years, but their historical, moral and educational significance remains actual and nowadays. The modern edition of the complete manuscript, along with introductory article and detailed scientific commentary, will become a significant contribution to representation of biography of S.P Botkin, to supplementation of written sources about the Russian-Turkish war of 1877-1878, and to comprehension of centuries-old Middle Eastern geopolitics of Russia.

["The letters of S. P. Botkin from Bulgaria. 1877": The history of publication of autograph]

The letters of S. P. Botkin from Bulgaria (1877) to his wife, E. A. Botkina (née Princess Obolenskaya), were published as travel diary in the journal "Vestnik Evropy" in 1892 and as separate book in 1893. The family events related to publication of epistolary were restored. For publication, material of private nature was abridged by E. A. Botkina. Then, passages with compromising criticism were removed by editor of the journal. In spite of good quality of prepared text, publication was postponed by E. A. Botkina herself and afterwards it was lingered on because of claims of censorial department. The role of N. A. Belogolovy, public figure and friend of S. P. Botkin of many years and M. M. Stasyulevich, a publisher, in final decision to publish epistolary is emphasized. The comparison of original and printed matter carried out for the first time, established that cuts made up to more than one third of author's text.

Morphological Analysis of the Respiratory Tract of Rats after Parenteral Administration of Silicon Dioxide Nanoparticles

Morphological analysis of the respiratory tract of Wistar rats was performed after a single parenteral administration of 12-nm silicon dioxide nanoparticles (1 ml, 2 mg/ml, intravenously) was performed. On day 21 and in 2, 4, and 6 months after the administration of nanoparticles, the development of macrophage infiltration in the interstitium of the respiratory tract was demonstrated by histological and immunohistochemical methods. The pool of alveolar macrophages increased in 4 months after administration (p=0.004) and returned to the control values in 6 months. The number of mast cells did not significantly change at all stages of the experiment. Connective tissue remodeling in the interstitium of the respiratory tract was not observed throughout the observation period.

Reaction of the Palatine Tonsillar Immunocompetent Cells to Irrigation of Crypts by Suspension of Silica Nanoparticles under Conditions of Chronic Tonsillitis

We studied the response of neutrophils, macrophages, and mast cells to local application of silica nanoparticles (10-20 nm). Histological examination of tonsillar postoperative material from 6 patients aged 24-44 years with recurrent tonsillitis was carried out. Irrigation of the tonsillar lacunae was carried out over 5 days before bilateral tonsillectomy: on the right by Polysorb MP suspension (1 g/liter), on the left by saline. The contact of nanoparticles with the mucosa led to a decrease in the number of cells expressing myeloperoxidase (p=0.02) and an increase in the count of CD68+ cells (p=0.04); the count of mast cells remained unchanged. Local use of medical adsorbent based on silica nanoparticles induced changes in cells due to their resorption by the tissue. Positive chemotaxis of CD68+ macrophages revealed in the tonsillar lymphoid tissue attested to stimulation of non-specific immunity and inductive phase of specific immunity. The authors hypothesized that internalization of medical nanoparticles by resident phagocytes of the mucosa could support targeted biodistribution of drugs in the palatine tonsils.

Preparation of N-succinyl-chitin nanoparticles and their applications in otoneurological pathology

Succinyl-chitin (SCH) nanoparticles were obtained by acylation of partially deacetylated chitin (DCH) nanofibers. Introduction of the succinyl moiety induced a partial amorphization of DCH, as viewed by X-ray diffraction, and increased the fractal dimension of the colloids from d_f = 1.2 (DCH) to 1.5-1.7 (SCH), as revealed by light scattering. The spherically symmetric form of the colloids remained almost unchanged, as indicated by the range of structure-sensitive ratios 1.0 < R_g/R_h < 1.2; the hydrodynamic diameter ranged from 200 to 300 nm. The cytoprotective activity of the SCH nanoparticles was evaluated in vivo in an acute hearing pathology model (220-250 g male Wistar rats, n = 90) following prophylactic and therapeutic administrations. Ototropic action was estimated using the amplitude of otoacoustic emissions at the frequency of the distortion product otoacoustic emissions in the range of 4-6.4 kHz before acoustic stimulation, as well as at 1 h, 24 h, and 7 days after acoustic stimulation. A dispersion of 0.3% SCH nanoparticles demonstrated prolonged ototropic action and earlier regeneration of hearing functions when compared to a meglumine sodium succinate solution. Thus, intravenous administration of the SCH nanoparticles increases the cycling time of exogenous succinate and improves biodistribution in tissues possessing a hemato-labyrinth barrier.

Potentiation of Otoprotective Effect of Hydrocortisone Immobilized on Povidone Nanoparticles under Conditions of Intravenous Injection

The otoprotective effect of immobilized hydrocortisone was studied on the model of acute acoustic injury to the auditory analyzer in male Wistar rats. The effects of true solution and suspension where polyvinylpyrrolidone particles (100-500 nm) served as dispersed phase (hydrocortisone concentration 5 mg/kg). The agents were administered immediately after continuous acoustic stimulation: 5 kHz tone, 110 dB for 2 h. The hearing status was evaluated by the amplitude of otoacoustic emission at the distortion product frequency (4-6.4 kHz) 1 and 24 h and 7 days after acoustic stimulation. Single injection of hydrocortisone suspension caused a more pronounced therapeutic effect within 1 day after acoustic stimulation.

[Last years of N. I. Pirogov (according to dairy of D. A. Skalon written in 1876-7878)]

Last years of N.I.Pirogov (according to dairy of D.A.Skalon written in 1876-1878). Excerpts from colonel D.A. Skalon's 1876-1878 diaries are published for the first time. The diaries detail his interactions with NI. Pirogov (1810-1881) and present a unique account on psychophysical state of the great Russian surgeon during the last years of his life. The testimony of an immediate witness pictures a hale old man with a choleric temperament, broad and creative mind, state-scale thinking, and diverse interests reaching far beyond medicine.

Pathomorphological peculiarities of damage to hair cells of the organ of corti in experimental sensorineural hearing loss

Pathomorphology of the organ of Corti was studied on models of acute and chronic sensorineural damage to the acoustic analyzer. Peculiarities of hair cell degeneration, necrosis, and apoptosis in the organ were studied by light and scanning electron microscopy. The type of pathomorphological substrate in abnormalities of the organ of Corti depends on the intensity of the destructive exposure, but not on the nature of otopathological factors.

Natural antioxidant L-carnosine inhibits LPO intensification in structures of the auditory analyzer under conditions of chronic exposure to aminoglycoside antibiotics

Intragastric administration of L-carnosine suspension to Wistar-Kyoto rats 3 days before and after 7-day course of intraperitoneal injections of ototoxic aminoglycoside antibiotic kanamycin compensated expenditures of tissue antioxidant systems and significantly eliminated kanamycin-induced intensification of MDA production in tissues of the membrane part of the cochlea and in the auditory cortex of the temporal lobe. L-NAME (competitive NO synthase inhibitor) also inhibited LPO, increased total antioxidant activity, and decreased ototoxicity of kanamycin, which confirms the contribution of NO into LPO intensification under conditions of aminoglycoside treatment. Inhibition of pathological intensification of LPO processes and increase in total antioxidant activity under conditions of induced acute aminoglycoside ototoxicity characterizes L-carnosine as a highly effective otoprotector.

Protective Effect of Carnosine on Excitable Structures of the Auditory Apparatus in Albino Rats with Acute Acoustic Trauma

We studied the effect of natural antioxidant carnosine on Wistar rats with experimental acoustic trauma of the auditory apparatus. Repeated intraperitoneal injection of carnosine in a dose of 200 mg/kg 12 and 0.5 h before modeling of acute acoustic trauma decreased the severity of degenerative and atrophic changes in the nuclei of hair cells in the cochleae. Carnosine compensated the deficiency of tissue antioxidant systems and suppressed generation of lipid peroxidation products in tissues of the membranous cochlea and auditory cortex of the temporal lobes. Carnosine holds much promise as a nonspecific otoprotector.

Protective effect of calcium channel blocker verapamil on morphological and functional state of hair cells of the organ of corti in experimental kanamycin-induced ototoxicity

The protective effect of verapamil against acute ototoxic sensorineural damage produced by intraperitoneal injections of kanamycin (50 mg/kg daily for 14 day) was studied on rats. The functional (otoacoustic emission), histological, and physiological methods proved the protective effect of daily injections of calcium channel blocker verapamil (2 mg/kg) on the state of hair cells of the organ of Corti.