LARYNX MYOFIBROBLASTIC TUMOR, A RARE CASE REPORT

Myofibroblastic tumour is extremely rare in the larynx, with just over 40 published cases. Despite being a benign tumour, they are tumours with a marked inflammatory character, local destruction and the possibility of degeneration to malignant histological types and with metastatic capacity. Anatomopathological differential diagnosis is fundamental in this cases.

Primary Inverted Papilloma of the Middle Ear

Significance Statement: Primary middle ear inverted papilloma is an exceedingly rare finding posing a diagnostic challenge, as symptomatology often mimics common clinical entities like serous otitis media. Clinical and radiological findings are not specific, whilst high recurrence rates, local destruction, and potential malignant transformation constitute an overall demanding surgical challenge, requiring aggressive procedures. We report the case of a primary inverted papilloma of the middle ear, discussing diagnostic and therapeutic issues.

Effect of power of ultrasound during micro-arc oxidation on morphology, elemental and phase composition of calcium phosphate coatings

The effect of the magnitude of the US (ultrasound) power applied during the MAO (micro arc oxidation) process on the morphology, elemental and phase composition of the CaP coatings was studied. The US at different power (50-200 W) applying during the MAO process led to the local destruction of the structure elements (spheres and pores) and local filling the pore spaces on the coating surface, and to the formation of local macro-pores inside the coatings near the substrate. Such morphological transformations led to the surface and structure heterogeneity of the coatings, increasing of the surface roughness from 3.0 to 4.5 μm and of the thickness from 50 to 60 μm. The US application at different power did not affect significantly the elemental composition of the coatings. At the same time, under applied US with power more than 100 W, the state of the coatings transformed from X-ray amorphous to the quasiamorphous with the small incorporation of crystalline phases of CaHPO4 and β-Ca2P2O7.

P.031 A Rare Canadian Case of Cervical Pyomyosistis Presenting as Occipital Neuralgia

Background: Pyomyositis is an infectious disease usually encountered in tropical regions. It typically occurs in immunocompromised hosts and most commonly affects lower limb muscles. Our patient was a healthy Canadian with an atypical presentation of cervical pyomyositis. Methods: We report a case of a healthy 22-year old woman presenting to the emergency department with unprovoked severe bilateral cervico-occipital pain and nuchal rigidity. She remained afebrile. Review of the literature was conducted to search for similar presentations. Results: A Computed Tomography scan of the head and neck demonstrated the presence of a ring enhancing lesion in the semispinalis capitis muscle extending from the occiput to the C4 level. The abscess was surgically drained and cultures grew staphylococcus aureus. The patient rapidly improved on intravenous antibiotics. Literature review revealed this to be the first Canadian case of cervical pyomyositis. Conclusions: Cervical pyomyositis can be complicated by local destruction of the vertebrae, septic shock, endocarditis, septic emboli, brain abscess or rhabdomyolysis. Early diagnosis and source control is necessary to reduce the risk of morbidity. Therefore, it is important to consider this rare disease in the differential diagnosis of cervicalgia even in healthy immunocompetent patients.

Dynamic response of the building construction system with a finite degree of freedom under a special action

Introduction. In the normative documents of a number of countries on the standardization of the protection of buildings and structures from progressive collapse, for the calculation analysis under special impact, such a concept as a “zone of possible local destruction” of a structural system is used, outlined by a fragment of the building frame in places of hypothetically removed structural elements. The purpose of identifying such most stressed zones in the form of substructures is engineering visibility of the consequences of an emergency impact with an assessment of the stress-strain state of elements falling into such a zone. In this regard, in the work under consideration, a variant of modeling the dynamic additional loading of the reinforced concrete frame of a multi-storey building caused by its structural restructuring is proposed, which makes it possible to determine the parameters of the dynamic response of the substructure in the form of a two-span continuous beam with a finite number of degrees of freedom and to model in more detail the zone of possible local destruction of the elements of the building frame at the sudden removal of one of the structural structures in this area. Materials and methods. The zone of possible local destruction of the building frame is modeled by a fragment of the structural system adjacent to this zone. The process of removing a column was simulated by applying a load P(t) in the opposite direction, equal to the force in the removed column, calculated when calculating the entire frame of the building. To solve the system of equations of motion of the substructure, we use the method of expansion in terms of natural vibration modes, which is well known in the dynamics of structures. Results. The results of theoretical studies of the dynamic effect of a reinforced concrete structural system of a building with a finite number of degrees of freedom during its sudden restructuring caused by a special emergency impact in the form of a hypothetical removal of one of the load-bearing structures are presented. Conclusions. The equations of motion of a substructure in the form of a two-span continuous beam with a finite number of degrees of freedom constructed on the basis of the theory of the dynamics of structures can be used to analyze the special limiting state of reinforced concrete elements of structural systems of frames of buildings and structures.

The use of endoscopic cryoapplicator in liver and gallbladder surgery

Purpose of the study. To investigate the efficacy of focal destruction tissues of local liver diseases, chole- and hemostasis of created endoscopic cryoapplicator in operations on the liver and gallbladder.Material and methods. Review the results of surgical treatment of 121 patients with various diseases of the liver (tumors, alveococcosis, parasitic and non-parasitic cysts) and gallbladder (chronic and acute cholecystitis) using a new endoscopic porous TiNi cryoapplicator. 49 patients were operated by an open method, 72 - laparoscopically. Hemo-and cholestatic control of the instrument was performed intraoperative and in postoperative period - by clinical condition of patient and by ultrasonography. Efficiency of destruction of focal liver diseases was investigated by histological examinations of surgical materials, is confirmed by the absence of relapses in the period from 4 to 6 years.The results. Cryoapplicator is simple in use, in sterilization, no energy consumption, can be used both in open surgery, particularly in arduous regions of the liver and laparoscopic procedures and, most importantly, patients with artificial cardiac pacemakers.Cryodestruction of the liver stump after its resection and the bed of the gallbladder after cholecystectomy reduces blood loss by 30-40%, and also helps to reduce the number of relapses of the disease. There were not observed bleeding and bile leakage in postoperative period. Histological examination proved picture of avascular necrosis, a violation of tissue structure of subjected to destruction liver focal diseases, death of epithelial lining of non-parasitic cysts and membranes of echinococcal cysts. There were not diseases recurrences in the period from 4 to 6 years.Conclusion. Endoscopic porous TiNi cryoapplicator is simple and convenient in use, it has a good hemo- and cholestatic effects, pronounced effect to local destruction of liver focal diseases, can be recommended for open and laparoscopic operations on liver.

STRATEGY AND EXPERIENCE OF INFANTILE HEMANGIOMA TREATMENT

Objective. To analyze the treatment results of patients with infantile hemangiomas using various methods. Methods. The study is grounded on the treatment results of children (n=189) with infantile hemangiomas during the period of 2000-2018 years. All patients were divided into the groups: 1) dynamic observation - 23 (12.2%) children; 2) local destruction - 78 (41.3%); 3) surgical treatment - 22 (11.6%); 4) drug therapy - 66 (34.9%) patients. The interstitial coagulation (n=28) and electrocoagulation of hemangioma (n=50) were applied for the local destruction. 18 patients underwent the complete removal of hemangioma and 4 - segmental resection of tumor with the subsequent propranolol treatment. Propranolol was used for the drug treatment and it was combined with the topical application of timolol (n=13). Results. Hemangioma regression was registered in 18 (78.3%) patients of the first group. Among the patients of the second group, involution of hemangioma was observed in 26 (92.6%) patients when the interstitial coagulation was applied and 2 (7.4%) children had hemangioma recurrence. A strongpositiveeffect can be reached by electrocoagulation of superficial hemangiomas (all patients). With primary radical intervention, complete cure was noted in all children, and with segmental resection only one (4.5%) child had a relapse. Keloid scars were formed in 3 (13.6%) children after surgery. Propranolol seemed to be effective in treating hemangiomasinchildrenof all ages, and in 41 (62.1%) patients hemangiomas completely disappeared. Conclusion. Before initiatingtherapy, thechildrenneed to be assessed for the contraindications and the treatment strategy.In case of infantile hemangioma should be individual based on the results of clinical investigation. Systemic propranolol treatment has gained rapid popularity as the treatment of choice for infantile hemangiomas and may be applied not only as the basic treatment, but also in combination with other methods. Surgical removal of hemangioma remains one of the common treatments components for children with infantile hemangiomas. What this paper adds Different variants of infantile hemangioma treatment have been analyzed: ranging from dynamic observation to surgical and systemic treatment. It has been shown, that in case of infantile hemangiomas, Beta-blockers have become the treatment of choice in case of the absence of contraindications; and surgical treatment is indicated in children with the risk of complications development.

Local Destruction of Tumors and Systemic Immune Effects

Current immune-based therapies signify a major advancement in cancer therapy; yet, they are not effective in the majority of patients. Physically based local destruction techniques have been shown to induce immunologic effects and are increasingly used in order to improve the outcome of immunotherapies. The various local destruction methods have different modes of action and there is considerable variation between the different techniques with respect to the ability and frequency to create a systemic anti-tumor immunologic effect. Since the abscopal effect is considered to be the best indicator of a relevant immunologic effect, the present review focused on the tissue changes associated with this effect in order to find determinants for a strong immunologic response, both when local destruction is used alone and combined with immunotherapy. In addition to the T cell-inflammation that was induced by all methods, the analysis indicated that it was important for an optimal outcome that the released antigens were not destroyed, tumor cell death was necrotic and tumor tissue perfusion was at least partially preserved allowing for antigen presentation, immune cell trafficking and reduction of hypoxia. Local treatment with controlled low level hyperthermia met these requisites and was especially prone to result in abscopal immune activity on its own.

Method of ensuring the survivability of highly mobile computer networks

The article discusses the features of the functioning of mobile computer networks based on small-sized aircraft (highly mobile computer networks). It is shown that such networks, in contrast to stationary or low-mobile ones, have a low level of survivability in case of local damage to their nodes. The purpose of the article is to develop a method for ensuring the survivability of highly mobile computer networks under conditions of destructive external influences, which leads to local destruction of network nodes or links between them, using the method of assessing survivability at all stages of network functioning, by changing the main function to implement all available strategies for the functioning of the network when determining the critical values of the integrity of the network and its ability to perform at least one of the available functions. The results obtained allow: to continue the development of theoretical research in the development of strategies for managing highly mobile computer networks in extreme situations; to develop an applied solution to ensure the survivability of highly mobile computer networks by building multifunctional or redundant structures, increasing the value of their redundancy. The studies allow us to conclude that the proposed method can be used at the design stages of highly mobile computer networks, characterized by increased survivability and capable of functioning in conditions of multiple local damages without catastrophic destructive consequences for the network structure.

Destruction of microplastics in the natural environment

<p>Morphological structure and chemical composition of environmental microplastics (MPs) extracted from water and bottom sediments of Lake Onego were studied. Raman spectroscopy was used to identify MPs polymer types and scanning electron microscopy with energy dispersive microanalysis was used to study the morphology and trace elements composition of inclusions on their surface. The features of the destruction of MPs, as well as the presence of various chemical elements on their surface including heavy metals, were investigated. Four main mechanisms of MPs microdestruction have been identified: (1) Local destruction of monophasic MPs caused by local oxidation and cleavage of thin flakes and fragments with the formation of nanoscale plastics. (2) The destruction of multiphase microplastics predominantly determined by the selective destruction of one of the phases of the composite, for example, the ligament scission between the individual components of the plastic with their separation. (3) Microbiological destruction of MPs under the influence of diatoms by fixing spores of diatoms on defects of MPs with their subsequent growth, deflection, and separation of nanoscale polymer particles. (4) Mineralogical destruction of MPs associated with the sorption of chemical elements and crystallization of nanocrystals, which under appropriate conditions begin to grow and break-up the MPs accelerating the process of its destruction. The last mechanism have not yet been reported. These mechanisms initiate nanoplastics formation, which increases particles mobility in the aquatic environment and their threat to water organisms. At the same time, the fouling with diatoms (with a silica shell) and the sorption of heavy elements increase the bulk specific density of MPs and contribute to its accumulation in bottom sediments.</p><p>The study was supported by the Russian Science Foundation grant number 19-17-00035.</p>