MINERALIZATION OF TEETH ENAMEL AFTER ERUPTION.

OBJECTIVE: The aim: The paper was aimed at the study of the processes of mineralization of the enamel of the permanent tooth after its eruption. PATIENTS AND METHODS: Materials and methods: To study the structure of the enamel of permanent teeth has been carried out using light and electron microscopy. The study of the process of the development of the primordia of the permanent teeth involved 10 culled puppies of 30-40 days of age. Microscopic, electron microscopic, immunohistochemical methods of research have been used to study the processes of histogenesis. RESULTS: Results: The studies show that in the postnatal period, the formation of the crown, externally covered with cuticular epithelium, marks the formation of the primordium of the permanent tooth at the follicle stage. After eruption of a tooth, different parts of its crown have three individual structural and functional barriers to enamel biomineralization. The first one is provided by the cuticular epithelium of the pitted areas of the crown, which ensures filtering of the salivary fluid from the protein deposit in the form of a pellicle. The second barrier is defined on the lateral and cuspidate surfaces of the enamel, where the cuticle is erased or poorly expressed. The third structural and functional barrier of enamel biomineralization is located in the cervical portion of teeth of different classes. CONCLUSION: Conclusions: Different areas of the enamel in the tooth crown have specific filtration barriers, which can be distinguished as follows: pit-and-fissure-and-groove, cuspidateand-approximal, and cervical barriers. The cuticle is poorly expressed or totally absent on the cusps of the tooth crowns in contrast to pitted areas.

DENTAL CROWN BIOMINERALIZATION DURING ITS HISTOGENESIS.

OBJECTIVE: The aim: Thepaper wasaimedat thestudyof thebiomineralization processesofa permanentdental crown in thepostnatal period of histogenesis. PATIENTS AND METHODS: Materials and methods: The study involved 30 culled puppies aged 30-40 days. To study the histogenesis of the germs of the permanent tooth from the cuticular epithelium in the postnatal period microscopic, electron microscopic, immunohistochemical methods of study have been used. RESULTS: Results: The studies show that in the postnatal period, the maturation of the germ of a permanent tooth starts with the synthesis of cells of the cuticular epithelium of the organic stroma, capable of subsequent mineralization. Differentiation of the proameloblasts, located on the surface of the dental papillary mesenchyma, at the early stages of histogenesis, is strongly associated with the appearance of a specific protein taftelin. Origination of secretory ameloblasts, which produce the protein enamelin, triggers the process of secondary biomineralization of the enamel. The terminal processes of the secretory ameloblasts produce the protein in the form of layers that overlap each other at a certain angle. Such layering of the structures of enamel and dentin contributes to the S-shaped maturation of the hard tooth tissues, strengthening them considerably. At the follicle stage, maturation of the dental crown, coated with cuticular epithelium, occurs. Invaginations of the cuticular epithelium form a characteristic topography of the dental crown, and enamel projections are further formed by the ameloblasts. Epitheliocytes of the inner layer of the enamel organ have desmosomal connections that allow the filtration of the salivary fluid at the stage of the enamel trophism. CONCLUSION: Conclusions: The findings of the study suggest that, normally, due to the cuticular epithelium, filtration of the salivary fluid occurs with protein deposition on it and subsequent infiltration of the calcium salts into the subjacent enamel.

Current view on the structure and function of the frontal sinus: literature review.

OBJECTIVE: Introduction: Chronic inflammatory diseases of the mucous membranes of the nose, paranasal sinuses, and pharynx are the most common pathology of the upper airways. Pathological processes develop more often in the maxillary and ethmoidal sinuses than in the frontal ones; however, the clinical course of frontitis is more severe. Fundamental understanding of the specific structure of frontal sinuses is crucial in the awareness of the precursors of the onset and development of its pathology, the choice of methods of diagnostics and treatment. The aim: The paper was aimed at the analysis of the publications on current data related to the structure and functions of the human frontal sinus and its structural components. Materials and methods: The bibliosemantic method has been used during the study. Findings of the current research works on the study of the human frontal sinus have been analyzed. RESULTS: Review: The resulting analysis shows that despite the significant amount of research works devoted to the study of the structure and functions of the frontal sinus, the morphofunctional features of its mucosa and the state of local immune protection remained unknown for a long time. CONCLUSION: Conclusions: The resulting literature review showed that the study of the morphofunctional properties of the frontal sinus is relevant to date that is reflected in the number of research works, elucidating its topographoanatomical, histological, physiological and immunohistochemical features.

The use of immunohistochemical methods in the study of morphofunctional features of the human paranasal sinuses: literature review.

OBJECTIVE: Introduction:Chronic inflammatory diseases of the mucous membrane of the nose, paranasal sinuses, and pharynx are the most widespread pathology of the upper airways. The thorough study of the features of the organization of local immune protection of the mucous membrane of the paranasal sinuses is crucial for the deep understanding of the causes of the onset and development of this and other pathologies of the paranasal sinuses, the choice of methods of diagnostics and treatment. Consequently, immunohistochemical studies are of great potential and have become preferable for great number of researchers. The aim: The paper was aimed at the analysis of the publications on the use of immunohistochemical methods in the study of the structural and functional features of the paranasal sinuses. PATIENTS AND METHODS: Materials and methods: The bibliosemantic method has been used during the study. Findings of the current research works on the use of immunohistochemical methods in the study of the paranasal sinuses have been analyzed. RESULTS: Review:The findings of the analysis shows that the use of immunohistochemical methods in the otorhinolaryngology is becoming more and more popular in the study of both morphofunctional features of the paranasal sinuses and in various experimental studies. CONCLUSION: Conclusion: The use of immunohistochemical methods in the study of the paranasal sinuses in both clinical otorhinolaryngology and theoretical morphology is relevant to date and is considered reasonable and perspective.

Stereomorphology of the glandular parenchyma of the inferoposterolateral area of human prostate gland.

OBJECTIVE: Introduction: The human prostate gland contains numerous tubular masses of different calibers in its parenchyma. They form the tubuloalveolar prostate glandules, constituting from numerous prostatic excretory ductules as well as major excretory ducts. The aim: The study was aimed at 3D visualization of individual microelements of the tubuloalveolar aggregations, localized within the peripheral area. PATIENTS AND METHODS: Materials and methods: To meet the objectives of the study a series of paraffin plane-parallel 4 µm sections has been obtained in the peripheral prostate area. The serial sections were stained with hematoxylin and eosin. After the analysis of the series of sections, the graphical two-dimensional and plastic 3D reconstructions of the investigated microobjects have been made sequentially in depth. RESULTS: Results: Presence of the epithelial creases and invaginations of the wall in the luminal contour of tubuloalveolar aggregations of the prostate has been found. Creases can be solitary, multiple, or wavy; they can be localized both symmetrically and asymmetrically, with different heights and thicknesses. Intraluminal invaginations, along with the epithelial crease, contain a stromal muscle component with localized blood loop-shaped microvessel. The creases of the glandular epithelium and intraluminal invaginations can "overlap" the lumens of the tubuloalveolar aggregations up to 2/3 of the width, making the inner lumen sinuous that influences the laminar flow of the liquid. CONCLUSION: Conclusions: Alternation of the considerable enlargement and narrowing of the inner diameter is common for the tubuloalveolar aggregations which can affect the secreta deposition and movement.

Chronic systemic inflammation in the pathogenesis of comorbid pathology and it's correction.

OBJECTIVE: Introduction: The paper presents the findings of our own study on the changes of the systemic inflammation in patients with type 2 diabetes mellitus (DM2) and ischemic heart disease (IHD) during the combination treatment with metformin and pioglitazone. The aim of the paper is to define the dynamics of the systemic inflammation in patients with type 2 diabetes mellitus and ischemic heart disease in combination treatment with metformin and pioglitazone. PATIENTS AND METHODS: Meterials and methods: 95 patients with IHD concomitant with DM2 have been treated. Patients, enrolled into study, have been randomized into 2 groups: the comparison group (n=37) treated with metformin andsulphonylureas, and the study group (n=58) treated with metformin and pioglitazone. The proposed course of therapy lasted 6 months. RESULTS: Results and conclusions: Before, after 3 and 6 months of treatment the control over the state of inflammatory responses was made and C-reactive protein, tumor necrosis factor-alpha, Interleukin-6 was assessed. The resulting data confirmed a statistically significant reduction under the effect of the combined treatment with the proposed combination of marker drugs and the degree of chronic systemic inflammation that is specific for IHD and DM2, which has a positive impact on the development and progress of IHD in DM2 patients, is well tolerated and can be considered as a pathogenic factor in the therapy of the presented comorbid nosologies.

Morphological substantiation for acute immobilization stress-related disorders of adaptation mechanisms.

INTRODUCTION: Nowadays, an individual is being constantly accompanied by stresses in his/her everyday life. Stress reactions, produced in the process of evolution, have become the organisms' response to emergency action or pathological factors and are the important link in adaptation process. However, the adverse course of stress reaction can lead to derangement of the adaptation mechanisms in the body and become the element of the pathogenesis of various diseases. THE AIM: The study was aimed at morphological substantiation of derangement of adaptation mechanisms in white Wistar rats caused by the acute immobilization stress. MATERIALS AND METHODS: 40 Wistar white male rats of 240-260 g body weight aged 8-10 months were involved into study. 20 laboratory animals were assigned to the main group and the rest 20 rats formed the control (II) group. Experimental stress model was simulated by immobilization of rats, lying supine, for 6 hours. Morphological examination of heart, lungs and kidneys was carried out after animals' decapitation, which proved the derangement of rats' adaptation mechanisms caused by the acute immobilization stress. RESULTS: It has been established that six-hour immobility of rats, lying in the supine position, led to the development of destructive phenomena, hemorrhagic lesions and impaired hemomicrocirculation. Microscopically, the acute immobilization stress causes significant subendocardial hemorrhages, plethora of vessels of hemomicrocirculatory flow with dysdiemorrhysis, myocardial intersticium edema in the heart. Histologically, immobilization-induced trauma causes significant hemodynamic disorders, spasm of arterioles and considerable venous hyperemia, concomitant with microthrombosis in kidneys; at the same time dystrophic lesions and desquamation of epithelium of renal tubules has been observed in renal corpuscles. CONCLUSION: The abovementioned structural changes can contribute to origination and development of multiple lesions, demonstrating the morphologically grounded role of the acute immobilization stress as the factor for disorders of adaptive mechanisms.

Morphological and immunohistochemical characteristics of human trigeminal ganglion neurons in the prenatal period of development.

INTRODUCTION: Data related to the amount, size and morphological characteristics of cell elements of sensory ganglia at different stages of prenatal development has not been fully elucidated in recent scientific publications. At the same time publications considering the study of cell structure of trigeminal ganglion in the postnatal period confirm heterogeneity of its neurons. The aim of the research was to study morphological and immunohistochemical characteristics of human trigeminal ganglion neurons at 12-14 weeks of prenatal development. MATERIAL AND METHODS: The study was made on 24 trigeminal ganglions of 12 human fetuses at 12 to 14 weeks of prenatal development after abortion made on social and medical indications. RESULTS: At the studied period of the intrauterine development nerve cells of the trigeminal ganglion significantly differed in size, tinctorial properties and degree of argentophility of the perikaryon. At the same time, the number of small nerve cells with an average diameter of less than 15 µm prevailed. Immunohistochemical study allowed detecting the apparent Bcl-2 expression in the overwhelming number of small neurons; the expression of this marker has been observed in 50% of cells of the medium-sized neurons. No Bcl-2 expression has been found in most of the large neurons. Almost all the neurons, regardless of the size, showed moderate Ki-67 expression, protein S-100. VEGF expression has also occurred in the vast majority of the nerve cells of all size groups. CONCLUSIONS: 1. Human trigeminal ganglion neurons both at 12-14 weeks of prenatal development and in postnatal period are represented by heterogeneous population. 2. Polymorphism of trigeminal ganglion neurons has been found by all applied techniques. 3. Detected polymorphism is the evidence of processes of maturation and differentiation of neurons in human trigeminal ganglion at 12-14 weeks of prenatal development.

The use of various models of chronic immobilization stress in experimental studies.

INTRODUCTION: Stress is defined as a complex of protective and disturbing responses of the organism, generated in the process of the evolution, which occur as a result of neuroendocrine and metabolic alterations in response to the impact of emergency or pathological factors. Hence, stress is an important link of the adaptive mechanism; however, its adverse course can contribute to pathogenesis of many diseases. The problem of stress, which has been under study for years, is still a relevant topic to be investigated. AIM: The paper was aimed at comparison of various models of chronic immobilization stress based on the published data and findings from our own research. MATERIALS AND METHODS: The comparative analysis of the various techniques of chronic immobilization stress simulation in rats has been carried out on the basis of published data and findings of our own studies. RESULTS: It has been shown that the model, proposed by the investigators from the Ukrainian Medical Stomatological Academy aids in reducing the time of experimental study, does not require sophisticated equipment and the use of additional stressors, at night time, in particular, as well as enables animals' restraint in the convenient morning time. CONCLUSIONS: This technique is easy-to-use and can be applied while studying the influence of the immobilization stress on the body.

Current studies of ukrainian researchers of stress impact on chest organs: literature review.

OBJECTIVE: Introduction: Stress reactions allow the body to adapt to the various environmental factors using the universal complex of neurohumoral reactions. Excessive stress reduces adaptability of the body and can initiate the onset and development of various pathologies. In recent years, Ukrainian scientists have completed a series of studies on the analysis of various aspects of the stress effect on the body. Aim: The paper was aimed at the analysis of the national medical publications, devoted to the study of the impact of stress on the chest organs. PATIENTS AND METHODS: Material and Methods: The bibliosemantic method has been used during the study. Findings of the contemporary scientific studies devoted to the effect of stress on the chest organs have been analyzed. RESULTS: Results: The analysis shows that despite a long history of stress-related investigations, the study of the problem of stress remains relevant to date. Scientific researches elicit the new aspects of the impact of stress on the body, particularly on the chest organs. CONCLUSION: Conclusion: Recent investigations of Ukrainian scientists assist in better understanding of the essence of the stress-related morphofunctional changes that occur in the lungs, heart and esophagus. The findings will be helpful in the search for ways to prevent and treat stress-induced pathological processes, since the problem of stress remains to be solved to date.