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1.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36499057

RESUMEN

The interaction of the T-cell receptor (TCR) with a peptide in the major histocompatibility complex (pMHC) plays a central role in the adaptive immunity of higher chordates. Due to the high specificity and sensitivity of this process, the immune system quickly recognizes and efficiently responds to the appearance of foreign and altered self-antigens. This is important for ensuring anti-infectious and antitumor immunity, in addition to maintaining self-tolerance. The most common parameter used for assessing the specificity of TCR-pMHC interaction is affinity. This thermodynamic characteristic is widely used not only in various theoretical aspects, but also in practice, for example, in the engineering of various T-cell products with a chimeric (CAR-T) or artificial (TCR-engineered T-cell) antigen receptor. However, increasing data reveal the fact that, in addition to the thermodynamic component, the specificity of antigen recognition is based on the kinetics and mechanics of the process, having even greater influence on the selectivity of the process and T lymphocyte activation than affinity. Therefore, the kinetic and mechanical aspects of antigen recognition should be taken into account when designing artificial antigen receptors, especially those that recognize antigens in the MHC complex. This review describes the current understanding of the nature of the TCR-pMHC interaction, in addition to the thermodynamic, kinetic, and mechanical principles underlying the specificity and high sensitivity of this interaction.


Asunto(s)
Receptores de Antígenos de Linfocitos T , Receptores Quiméricos de Antígenos , Unión Proteica , Receptores de Antígenos de Linfocitos T/metabolismo , Complejo Mayor de Histocompatibilidad , Antígenos de Histocompatibilidad/metabolismo , Péptidos/metabolismo , Receptores Quiméricos de Antígenos/genética
2.
J Clin Endocrinol Metab ; 91(11): 4344-51, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16912122

RESUMEN

CONTEXT: Due to the Chornobyl accident, millions were exposed to radioactive isotopes of iodine and some received appreciable iodine 131 (131I) doses. A subsequent increase in thyroid cancer has been largely attributed to this exposure, but evidence concerning autoimmune thyroiditis (AIT) remains inconclusive. OBJECTIVE: The objective of the study was to quantify risk of AIT after 131I exposure. DESIGN/SETTING/PARTICIPANTS: Baseline data were collected from the first screening cycle (1998-2000) of a large cohort of radiation-exposed individuals (n = 12,240), residents of contaminated, iodine-deficient territories of Ukraine. Study individuals were under the age of 18 yr on April 26, 1986, and had thyroid radioactivity measurements made shortly after the accident. OUTCOMES: AIT was defined a priori based on various combinations of elevated antibodies to thyroid peroxidase (ATPO), TSH, and clinical findings; elevated ATPO were considered to be an indicator of thyroid autoimmunity. RESULTS: No significant association was found between 131I thyroid dose estimates and AIT, but prevalence of elevated ATPO demonstrated a modest, significant association with 131I that was well described by several concave models. This relationship was apparent in individuals with moderately elevated ATPO and euthyroid, thyroid disease-free individuals. CONCLUSIONS: Twelve to 14 yr after the Chornobyl accident, no radiation-related increase in prevalence of AIT was found in a large cohort study, the first in which 131I thyroid doses were estimated using individual radioactivity measurements. However, a dose-response relationship with ATPO prevalence raises the possibility that clinically important changes may occur over time. Thus, further follow-up and analysis of prospective data in this cohort are necessary.


Asunto(s)
Carcinoma/epidemiología , Accidente Nuclear de Chernóbil , Radioisótopos de Yodo/efectos adversos , Neoplasias Inducidas por Radiación/epidemiología , Enfermedades de la Tiroides/epidemiología , Neoplasias de la Tiroides/epidemiología , Tiroiditis Autoinmune/epidemiología , Adolescente , Autoanticuerpos/sangre , Autoantígenos/inmunología , Niño , Preescolar , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Lactante , Recién Nacido , Yoduro Peroxidasa/inmunología , Proteínas de Unión a Hierro/inmunología , Masculino , Tamizaje Masivo/métodos , Dosis de Radiación , Ucrania/epidemiología
3.
Lik Sprava ; (2): 12-5, 2003.
Artículo en Ruso | MEDLINE | ID: mdl-12774465

RESUMEN

On the basis of findings from the structural analysis of 21 nasal mucosa biopsy specimens of patients with chronic rhinitis including 12 participants in liquidation of the consequences of the Chernobyl accident using morphometric methods, signs of morphofunctional insufficiency of the nasal epithelium are verified. Mechanisms of this phenomenon development are discussed.


Asunto(s)
Mosaicismo/patología , Mucosa Nasal/patología , Exposición Profesional/efectos adversos , Centrales Eléctricas , Liberación de Radiactividad Peligrosa , Enfermedad Crónica , Humanos , Personal Militar , Mucosa Nasal/efectos de la radiación , Rinitis/etiología , Rinitis/patología , Ucrania
4.
Mikrobiol Z ; 63(1): 41-50, 2001.
Artículo en Ruso | MEDLINE | ID: mdl-11392771

RESUMEN

Bronchial bioptates of 97 liquidators of the Chernobyl accident consequences with chronic bronchitis and 23 patients of control nosological group as well as sputum (174 persons) and BAL (22 persons) of liquidators with chronic obstructive lung disease (COLD) were studied to define pathogenic role of automicroflora in the development of lung diseases. Such methods as electron microscopy, immunohistochemistry and microbiology were used. The revealed invasion of microorganisms occurred against the background of pathology of superficial bronchial epithelium with a decrease of HLA-DR and CD23 lymphocytes and increase of CD1c lymphocytes in lamina propria of bronchial mucosa of the liquidators. Verification of microorganisms characteristic of the upper respiratory tracts and atypical presence of Escherichia coli were found in the contents of the lower parts of broncho-pulmonary system of the liquidators. The obtained results testify to the activation of automicroflora and appearance of pathogenic microorganisms were caused by deterioration of specific and non-specific immune protection in liquidators with COLD.


Asunto(s)
Bronquios/microbiología , Membrana Mucosa/microbiología , Centrales Eléctricas , Liberación de Radiactividad Peligrosa , Humanos , Inmunohistoquímica , Microscopía Electrónica , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Ucrania
5.
Tsitol Genet ; 33(1): 15-24, 1999.
Artículo en Ruso | MEDLINE | ID: mdl-10330694

RESUMEN

Bronchial biopsies from persons exposed to radiation after the Chernobyl accident with clinically verified chronic bronchitis were studied by electron microscopy. The results demonstrate transformed alterative, compensatory-adaptive and inflammatory reactions in bronchial mucosa of contingent. Nevertheless, their integral significance does not alter the nosologic form, and some structural equivalents have dynamic expression.


Asunto(s)
Bronquios/ultraestructura , Bronquitis/patología , Exposición Profesional/efectos adversos , Centrales Eléctricas , Liberación de Radiactividad Peligrosa , Adulto , Anciano , Biopsia , Bronquios/efectos de la radiación , Enfermedad Crónica , Femenino , Humanos , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Membrana Mucosa/efectos de la radiación , Membrana Mucosa/ultraestructura , Ucrania
6.
Lik Sprava ; (6): 7-10, 1998 Aug.
Artículo en Ucraniano | MEDLINE | ID: mdl-9844859

RESUMEN

Results are submitted of a complex structural analysis of 200 gastrobiopsies taken in those subjects with chronic gastritis who took part in the elimination of the aftermath of the Chernobyl accident, as well as in patients of a control nosologic group with no history of a radiation-factor exposure. The liquidators versus control patients demonstrated morphofunctional changes in gastric mucosa as potential manifestations of induced pathomorphosis of the condition. A number of propositions have been stated concerning features of morphogenesis of pathological processes in gastric mucosa under chronic gastritis in liquidators of the effects of the Chernobyl disaster.


Asunto(s)
Mucosa Gástrica/patología , Gastritis/patología , Personal Militar , Centrales Eléctricas , Liberación de Radiactividad Peligrosa , Biopsia , Enfermedad Crónica , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiología , Mucosa Gástrica/efectos de la radiación , Gastritis/etiología , Gastritis/metabolismo , Gastritis/microbiología , Infecciones por Helicobacter/etiología , Infecciones por Helicobacter/metabolismo , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/patología , Helicobacter pylori/aislamiento & purificación , Histocitoquímica , Humanos , Masculino , Ucrania
7.
Lik Sprava ; (2): 45-8, 1998.
Artículo en Ruso | MEDLINE | ID: mdl-9670653

RESUMEN

The importance is substantiated of morphologic verification of H. pylori infection in gastric mucosa in chronic gastritis. Based on the material of gastrobiopsies from 111 patients with chronic gastritis, 77 of whom took part in the elimination of the effects of the Chernobyl disaster, informative value was confirmed of different methods of structural analysis in respect of H. pylori. Arguments are advanced for optimization of therapeutic policy in H. pylori-associated gastritis.


Asunto(s)
Mucosa Gástrica/patología , Gastritis/patología , Infecciones por Helicobacter/patología , Helicobacter pylori , Biopsia , Enfermedad Crónica , Mucosa Gástrica/microbiología , Gastritis/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/aislamiento & purificación , Técnicas Histológicas , Humanos , Masculino , Personal Militar , Centrales Eléctricas , Liberación de Radiactividad Peligrosa , Coloración y Etiquetado/métodos , Ucrania
9.
Lik Sprava ; (5-6): 67-70, 1996.
Artículo en Ruso | MEDLINE | ID: mdl-9377404

RESUMEN

Autoimmune affections of the thyroid gland were found to be on the increase as were Hashimoto's disease and follicular adenoma, as evidenced by a pathomorphic study in surgically removed thyroid glands of 12684 patients over 1984-1993. Rise in the frequency of malignant tumors was moderate. Increase in the incidence of papillary microcarcinoma against the background of another surgical pathology of the thyroid gland may be an unfavourable prognostic sign of further growth of morbidity of clinically manifest forms of carcinoma in Kiev and the Kiev Province.


Asunto(s)
Enfermedades Autoinmunes/epidemiología , Exposición a Riesgos Ambientales/efectos adversos , Centrales Eléctricas , Traumatismos por Radiación/epidemiología , Liberación de Radiactividad Peligrosa , Enfermedades de la Tiroides/epidemiología , Población Urbana , Adolescente , Adulto , Anciano , Enfermedades Autoinmunes/etiología , Enfermedades Autoinmunes/cirugía , Niño , Exposición a Riesgos Ambientales/estadística & datos numéricos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias Inducidas por Radiación/epidemiología , Neoplasias Inducidas por Radiación/etiología , Neoplasias Inducidas por Radiación/cirugía , Traumatismos por Radiación/etiología , Traumatismos por Radiación/cirugía , Enfermedades de la Tiroides/etiología , Enfermedades de la Tiroides/cirugía , Ucrania/epidemiología , Población Urbana/estadística & datos numéricos
10.
Urol Nefrol (Mosk) ; (6): 46-8, 1993.
Artículo en Ruso | MEDLINE | ID: mdl-8160323

RESUMEN

T-lymphocyte E-receptor activity, mobility of the surface and deep parts of lymphocytic membrane lipid bilayer and membrane transport function were studied in 47 patients with chronic renal failure (16 had a conservatively curable and 31 terminal stages). A rosette test, polarization of the fluorescent probes I-anilino-naphthaleno-8-sulfonate and pyrene, inclusion of 14C-uridine into immunocompetent cells were employed, respectively. The investigations demonstrate morphofunctional instability of the lymphocytic membranes as indicated by shifts in RFC E-receptor activity, in reduced microviscosity of the lipid bilayer and transport dysfunction. The disturbances progress with deterioration of renal function with their peak at the terminal stage of the disease. It is suggested that morphofunctional damage to the lymphocyte membranes cause, among other factors, lymphocytopenia and secondary immunodeficiency in chronic renal failure.


Asunto(s)
Fallo Renal Crónico/inmunología , Complejo GPIb-IX de Glicoproteína Plaquetaria , Glicoproteínas de Membrana Plaquetaria , Linfocitos T/inmunología , Membrana Celular/inmunología , Eritrocitos/inmunología , Humanos , Síndromes de Inmunodeficiencia/etiología , Síndromes de Inmunodeficiencia/inmunología , Fallo Renal Crónico/complicaciones , Linfopenia/etiología , Linfopenia/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Superficie Celular/inmunología , Formación de Roseta
11.
Ter Arkh ; 65(6): 43-5, 1993.
Artículo en Ruso | MEDLINE | ID: mdl-8397446

RESUMEN

A rosette test, fluorescent probing (1-aniline-naphthaline-8-sulfonate and pyrene) and 14C-uridine inclusion into immuno-competent cells were used to investigate T-lymphocyte membrane E-receptor activity, mobility of the surface and deep parts of lymphocytic membrane lipid bilayer, and membrane transport, respectively. A total of 16 patients with conservatively curable and 31 patients with a terminal stage of chronic renal failure (CRF) were examined. The lymphocytic membranes were found unstable: E-receptor activity of RFC changed, microviscosity of the surface and deep lipid bilayer diminished, the transport function got disturbed. These phenomena significantly progress with deterioration of renal function. It is evident that morphofunctional damage to lymphocytic membranes may be a reason of lymphocytopenia and secondary immunodeficiency in CRF patients.


Asunto(s)
Fallo Renal Crónico/sangre , Fluidez de la Membrana , Linfocitos T/fisiología , Membrana Celular/fisiología , Eritrocitos/fisiología , Colorantes Fluorescentes , Humanos , Fallo Renal Crónico/etiología , Membrana Dobles de Lípidos/sangre , Receptores de Superficie Celular/fisiología , Formación de Roseta , Viscosidad
13.
Vrach Delo ; (2): 22-4, 1990 Feb.
Artículo en Ruso | MEDLINE | ID: mdl-2339542

RESUMEN

Regularities of structural changes and pathogenesis of pathological processes in the myocardium in intermediate form of ischemic heart disease indicates the necessity instituting adequate pathogenetic treatment and prophylaxis of hypertensive conditions, normalization of the coronary blood circulation, increase of the resistance of the myocardium to hypoxia, strengthening of reparative processes in the myocardium, activation of oxidation-reduction processes.


Asunto(s)
Enfermedad Coronaria/patología , Insuficiencia Cardíaca/patología , Adulto , Anciano , Biopsia , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/metabolismo , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/metabolismo , Histocitoquímica , Humanos , Hipertensión/complicaciones , Hipertensión/metabolismo , Hipertensión/patología , Microscopía Electrónica , Persona de Mediana Edad , Miocardio/metabolismo , Miocardio/ultraestructura , Oxidación-Reducción
14.
Ter Arkh ; 62(6): 84-8, 1990.
Artículo en Ruso | MEDLINE | ID: mdl-2218935

RESUMEN

Fifty-two patients with terminal renal failure (TRF) placed on elective hemodialysis were examined for serum lipids and red blood cell membranes with the aid of chromatographic separation of lipids in thin-layer silica gel on Silufol plates followed by densitometry. Spectrocytophotometry was employed to study red blood cell distribution on the basis of the content of lipoproteins in TRF patients. Fluidity of the lipid bilayer of the red blood cell membrane was measured on Hitachi spectrofluorimeter according to the degree of eximerization of fluorescent pyrene. Dyslipidemia manifested itself as hyperlipidemia, hypertriglyceridemia, hypercholesterolemia and hyperphosphatidylcholinemia. The lipid profile of the red blood cell membranes was found to be deranged, which was evidenced by the reduced content of lipoproteins, total phospholipids, triglycerides, and cholesterol esters. In addition, there was a significant rise in the content of free cholesterol, lysolecithin and phosphatidyl ethanolamine. Impairment of lipid exchange between blood serum and the red blood cell membrane in TRF patients is under discussion. The changes in the lipid spectrum of the red blood cell membranes mirror their morphofunctional failure, supported by derangement of fluidity of the lipid bilayer of the red blood cell membrane. Both increase of viscosity of the lipid bilayer of the red blood cell membrane caused by a high level of cholesterol in the membrane and changes in the cholesterol/phospholipid ratio and reduction of the lipid bilayer viscosity related to the rise of the content of membrane lysolecithin in part of TRF patients were discovered. Hemodialysis influenced the lipid content of blood serum, producing no effect on the lipid spectrum of the red blood cells membrane.


Asunto(s)
Membrana Eritrocítica/metabolismo , Fallo Renal Crónico/sangre , Lípidos de la Membrana/sangre , Adulto , Anciano , Cromatografía en Capa Delgada , Citofotometría , Humanos , Lactante , Fallo Renal Crónico/terapia , Lipoproteínas/sangre , Masculino , Persona de Mediana Edad , Diálisis Renal , Uremia/sangre , Uremia/terapia
15.
Vrach Delo ; (12): 36-7, 1989 Dec.
Artículo en Ruso | MEDLINE | ID: mdl-2629273

RESUMEN

It was established by histochemical and immunomorphological investigations that acute myocardial infarction results in an activation of the immune system of the body, immunomorphological changes in the lungs that plays a certain role in the pathogenesis of pneumonias in ischemic heart disease.


Asunto(s)
Enfermedad Coronaria/complicaciones , Neumonía/etiología , Formación de Anticuerpos/inmunología , Enfermedad Coronaria/inmunología , Enfermedad Coronaria/patología , Humanos , Inmunidad Celular/inmunología , Pulmón/inmunología , Pulmón/patología , Infarto del Miocardio/complicaciones , Infarto del Miocardio/inmunología , Infarto del Miocardio/patología , Neumonía/inmunología , Neumonía/patología
16.
Vrach Delo ; (9): 44-6, 1989 Sep.
Artículo en Ruso | MEDLINE | ID: mdl-2609619

RESUMEN

It was found that in isolated infundibular stenosis of the pulmonary artery a mass of muscle-fibrous tissue creates an obstacle to blood flow in the right ventricle. Morphogenetic regularities of compensatory and adaptive reactions in isolated infundibular stenosis are similar to those observed in hypertrophic cardiomyopathy. It may be suggested that abnormalities in the structure of the hypertrophied myocardium in isolated stenosis of the right ventricle infundibulum is a result of a fundamental error in the cardiac morphogenesis and not a reflection of increase of the degree of cardiac hypertrophy.


Asunto(s)
Estenosis de la Válvula Pulmonar/patología , Biopsia , Ventrículos Cardíacos/anomalías , Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/ultraestructura , Histocitoquímica , Humanos , Microscopía Electrónica , Arteria Pulmonar/anomalías , Arteria Pulmonar/metabolismo , Arteria Pulmonar/ultraestructura , Estenosis de la Válvula Pulmonar/congénito , Estenosis de la Válvula Pulmonar/etiología , Estenosis de la Válvula Pulmonar/metabolismo
19.
Arkh Patol ; 50(3): 66-72, 1988.
Artículo en Ruso | MEDLINE | ID: mdl-3288185

RESUMEN

A comprehensive histochemical, histoenzymatic, morphometric and ultrastructural evaluation of 27 autopsy and 22 biopsy specimens of the right ventricular endomyocardium, aimed at the study of dilatation cardiomyopathy, revealed alteration, compensatory and adaptation response in the cardiac muscle. The processes were recorded light-optically and ultrastructurally. Discussed are the mechanisms of the disease morphogenesis and ways of relevant therapeutic correction.


Asunto(s)
Cardiomiopatía Dilatada/etiología , Adolescente , Adulto , Biopsia , Cardiomiopatía Dilatada/patología , Femenino , Técnicas Histológicas , Humanos , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Miocardio/ultraestructura , Necrosis
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