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1.
Ophthalmic Genet ; 45(1): 23-27, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37997634

RESUMO

PURPOSE: Primary open-angle glaucoma (POAG) represents the most prevalent form of glaucoma and stands as a foremost contributor to irreversible vision impairment on a global scale. Despite notable strides made in comprehending the genetic underpinnings of POAG, investigations within the context of Russia remain constrained. METHODS: The study cohort comprised a total of 235 individuals, with 135 of them exhibiting various forms of glaucoma encompassing both POAG and (NTG, while the remaining 100 individuals served as control subjects. Each participant underwent a comprehensive ocular examination to ascertain their ocular health status. Genotyping of the relevant single nucleotide polymorphisms (SNPs) was carried out using the Taq Man genotyping assay. Specifically, the two SNPs under scrutiny were GNB3 rs5443 gene and ACE rs4646994. Statistical analysis was performed to evaluate the association of these SNPs with glaucoma risk. RESULTS: The presence of the T allele of rs5443 was found to be associated with NTG (p = .004). However, no statistically significant correlation was identified between this SNP and POAG (p = .88). CONCLUSION: This study provides evidence of an association between the T allele of rs5443 and a reduced susceptibility NTG within the Russian population. These observations augment the comprehension of the genetic underpinnings of glaucoma and hold potential implications for the prospective development of targeted therapeutic interventions.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Humanos , Genótipo , Glaucoma de Ângulo Aberto/genética , Pressão Intraocular , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos
2.
J Radiat Res ; 63(2): 202-212, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35146520

RESUMO

The long-term in vivo cytogenetic effects of high-dose radiation exposure can be traced in accidentally irradiated persons, and particularly useful for developing strategies of monitoring and therapy of such patients, as well as for elucidating the fundamental aspects of hematopoiesis and radiobiology. Using 24-color fluorescent in situ hybridization (mFISH), we analysed the frequency and the spectrum of chromosomal aberrations (CA) in peripheral blood lymphocytes of the Chernobyl Nuclear Power Plant (NPP) accident victim 30, 31, 32 and 33 years after acute accidental exposure to high-dose gamma radiation of the whole body. Totally, 993 metaphase cells were analyzed (or 219, 272, 258, 244 cells each year), of which 297 were aberrant. Our study demonstrated a constant aberrant cell frequency at 28% in 2016-2018 years, while in 2019, a significant increase up to 35% occurred due to contribution of significantly elevated frequency of simple aberrations in the absence of evident recent genotoxic factors. Four clonal aberrations were detected, three of which persisted for more than one year at a frequency up to 2.5% of analyzed cells. The distribution of 731 breakpoints per individual chromosomes was nearly proportional to their physical length, excepting Chromosomes 13 and 20, which were significantly breakpoint-deficient compared to the genome median rate. Monitoring of the long-term effects on chromosomal instability caused by radiation exposure is important for understanding and predicting the long-term effects of ionizing radiation.


Assuntos
Acidente Nuclear de Chernobyl , Aberrações Cromossômicas , Humanos , Hibridização in Situ Fluorescente , Linfócitos/efeitos da radiação , Centrais Nucleares , Sobreviventes
3.
Cells ; 9(12)2020 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-33260310

RESUMO

BACKGROUND: The search for an effective therapy for local radiation injuries (LRI) is urgent; one option is mesenchymal stem cells (MSC) derived from the placenta and their conditioned medium for the regenerative processes of the skin. METHODS: We used 80 animals, randomly assigned to four groups: control (C) animals that did not receive therapy; control with the introduction of culture medium concentrate (CM); introduction of MSCs (PL); introduction of CMPL. LRI modeling was performed on an X-ray machine at a dose of 110 Gy. Histological and immunohistochemical tests were performed. RESULTS: On the 112th day, the area of the open wound surface in the CMPL group was 6.7 times less than in the control group. Complete healing of the open wound surface of the skin in the CM group was observed in 40%, in CMPL 60%, in the PL group 20%, and in the C group there were no animals with a prolonged wound defect. A decrease in inflammatory processes was observed in the CMPL group. CONCLUSIONS: the use of a concentrate of conditioned MSCs (CMPL group) in severe LRI in laboratory animals accelerates the transition of the wound process to the stage of regeneration and epithelization.


Assuntos
Meios de Cultivo Condicionados/metabolismo , Células-Tronco Mesenquimais/citologia , Placenta/citologia , Lesões por Radiação/terapia , Animais , Feminino , Inflamação/terapia , Gravidez , Ratos , Ratos Wistar , Regeneração/fisiologia , Pele/citologia , Cicatrização/fisiologia
4.
PLoS One ; 15(10): e0240117, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33048966

RESUMO

Extracorporeal membrane oxygenation (ECMO) is increasingly used to treat severe cases of acute respiratory or cardiac failure. Hemorrhagic complications represent one of the most common complications during ECMO, and can be life threatening. The purpose of this study was to elucidate pathophysiological mechanisms of ECMO-associated hemorrhagic complications and their impact on standard and viscoelastic coagulation tests. The study cohort included 27 patients treated with VV-ECMO or VA-ECMO. Hemostasis was evaluated using standard coagulation tests and viscoelastic parameters investigated with rotational thromboelastometry. Anticoagulation and hemorrhagic complications were analyzed for up to seven days depending on ECMO duration. Hemorrhagic complications developed in 16 (59%) patients. There were 102 discrete hemorrhagic episodes among 116 24-hour-intervals, of which 27% were considered to be clinically significant. The highest number of ECMO-associated hemorrhages occurred on the 2nd and 3rd day of treatment. Respiratory tract bleeding was the most common hemorrhagic complication, occurring in 62% of the 24-hour intervals. All 24-hours-intervals were divided into two groups: "with bleeding" and "without bleeding". The probability of hemorrhage was significantly associated with abnormalities of four parameters: increased international normalized ratio (INR, sensitivity 71%, specificity 94%), increased prothrombin time (PT, sensitivity 90%, specificity 72%), decreased intrinsic pathway maximal clot firmness (MCFin, sensitivity 76%, specificity 89%), and increased extrinsic pathway clot formation time (CFTex, sensitivity 77%, specificity 87%). In conclusions, early ECMO-associated hemorrhagic complications are related to one traditional and two novel viscoelastic coagulation abnormalities: PT/INR elevation, reduced maximum clot firmness due to intrinsic pathway dysfunction (MCFin), and prolonged clot formation time due to extrinsic pathway dysfunction (CFTex). When managing hemostasis during ECMO, derangements in PT/INR, MCFin and CFTex should be focused on.


Assuntos
Oxigenação por Membrana Extracorpórea/efeitos adversos , Hemorragia/etiologia , Hemostasia , Adulto , Idoso , Idoso de 80 Anos ou mais , Coagulação Sanguínea , Testes de Coagulação Sanguínea , Feminino , Hemorragia/sangue , Hemorragia/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Nanomaterials (Basel) ; 10(5)2020 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-32429500

RESUMO

Gold nanoparticles (GNPs) emerged as promising antitumor radiosensitizers. However, the complex dependence of GNPs radiosensitization on the irradiation conditions remains unclear. In the present study, we investigated the impacts of the dose rate and photon energy on damage of the pBR322 plasmid DNA exposed to X-rays in the presence of 12 nm, 15 nm, 21 nm, and 26 nm GNPs. The greatest radiosensitization was observed for 26 nm GNPs. The sensitizer enhancement ratio (SER) 2.74 ± 0.61 was observed at 200 kVp with 2.4 mg/mL GNPs. Reduction of X-ray tube voltage to 150 and 100 kVp led to a smaller effect. We demonstrate for the first time that the change of the dose rate differentially influences on radiosensitization by GNPs of various sizes. For 12 nm, an increase in the dose rate from 0.2 to 2.1 Gy/min led to a ~1.13-fold increase in radiosensitization. No differences in the effect of 15 nm GNPs was found within the 0.85-2.1 Gy/min range. For 21 nm and 26 nm GNPs, an enhanced radiosensitization was observed along with the decreased dose rate from 2.1 to 0.2 Gy/min. Thus, GNPs are an effective tool for increasing the efficacy of orthovoltage X-ray exposure. However, careful selection of irradiation conditions is a key prerequisite for optimal radiosensitization efficacy.

6.
Stem Cells Cloning ; 11: 69-76, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464536

RESUMO

BACKGROUND: Mesenchymal stem cells based paracrine bioactive factors that deploy their task as an essential mechanism, but their efficiency for skin regeneration still requires clarification. METHODS: The mesenchymal stem cell-based paracrine factors were administered by subcutaneous injection of 0.5 mL peptides (general protein 8 mg/mL). These were performed after radiation on different days like the first, third, sixth, eighth, and 10th. To determine the consequences, we performed photography, planimetry, and preclinical test each week after 15 days of radiation. MSC-based peptides were injected into a rat that had radiation burns, and its observation encouraged cell-free therapeutic remedies to regenerate skin. Both control and experimental groups were exposed to 110 Gy of X-rays, which resulted in the formation of localized radiation burns on the skin (S=6 cm2) 15 days later. Thirty days after radiation, the wound stabilized (surface of the wound was S=2.2±0.2 cm2) and fluctuated throughout the course of the pathological process. RESULTS: The wounded area on the skin from the 15th to the 29th day after radiation was practically the same in both groups. The wounded area gradually reduced by 6.1±0.4 cm2 (experimental group) and 5.9±0.6 cm2 (control group) 15 days after radiation up to 2.2±0.3 cm2 (in both control and experimental groups) on the 29th day after radiation. However, starting from the 36th day, there was a constant reduction in the burn area in the experimental group up to 0.2±0.1 cm2 till the 71st day after radiation. CONCLUSION: In the control group, the area of the lesion ranged from 1.4±0.6 cm2 on the 50th day to 1.9±0.8 cm2 on the 71st day. During the 57th to the 71st day, the difference between the affected area in the experimental and control groups was 1:8. The experimental group has a significantly higher level of skin regeneration and significant decrease in the level of leukocyte infiltration, thereby reducing necrosis.

7.
Stud Health Technol Inform ; 248: 263-269, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29726446

RESUMO

The aim of the present work was to study the validity and prognostic accuracy of scores for assessing the severity of the condition in children with severe trauma, located in the Department of Anesthesiology and Resuscitation in the Clinical and Research Institute of Urgent Pediatric Surgery and Trauma. The prospective study was conducted using clinical and physiological data collected at the admission and during the first 24 hours of hospitalization from 474 patients. The validity and prognostic accuracy of prognostic scores were assessed by determining their discrimination and calibration ability. A comparison of the discriminatory ability of scores was carried out by comparing the areas under the ROC curves with the z-criterion. Four prognostic scores were included into the study: PRISM, APACHE II, ISS-RTS-TRISS, which were used for calculating the severity of injury and for prognosis of death. Score PTS was used for evaluating the severity index only. Our results indicate that only score ISS-RTS-TRISS may be useful in practice (has excellent discrimination ability and significant calibration ability). The other lack either discrimination ability (PRISM) or calibration ability (PTS, APACHE II). The result of the study has shown that only one of the four prognostic scores, ISS-RTS-TRISS, can be successfully used in everyday practice in the department of anesthesiology and resuscitation in the specialized hospital of children's traumatology to assess the severity of the condition, with the possibility of predicting the likelihood of a lethal outcome.


Assuntos
APACHE , Hospitais Especializados , Curva ROC , Índices de Gravidade do Trauma , Criança , Humanos , Escala de Gravidade do Ferimento , Prognóstico , Estudos Prospectivos , Ferimentos e Lesões
8.
J Radiat Res ; 59(suppl_2): ii40-ii47, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29415268

RESUMO

In the case of a severe radiation accident at a nuclear power station, the most important radiation hazard for the public is internal exposure of the thyroid to radioiodine. The purposes of this paper were (i) to compare countermeasures conducted (following the Chernobyl and Fukushima accidents) aimed at mitigation of exposure to the thyroid for the public, (ii) to present comparative estimates of doses to the thyroid and (iii) to derive lessons from the two accidents. The scale and time of countermeasures applied in the early phase of the accidents (sheltering, evacuation, and intake of stable iodine to block the thyroid) and at a later time (control of 131I concentration in foodstuffs) have been described. After the Chernobyl accident, the estimation of the thyroid doses for the public was mainly based on direct thyroid measurements of ~400 000 residents carried out within the first 2 months. The highest estimates of thyroid doses to children reached 50 Gy. After the Fukushima accident, the estimation of thyroid doses was based on radioecological models due to a lack of direct thyroid measurements (only slightly more than 1000 residents were measured). The highest estimates of thyroid doses to children were a few hundred mGy. Following the Chernobyl accident, ingestion of 131I through cows' milk was the dominant pathway. Following the Fukushima accident, it appears that inhalation of contaminated air was the dominant pathway. Some lessons learned following the Chernobyl and Fukushima accidents have been presented in this paper.


Assuntos
Acidente Nuclear de Chernobyl , Acidente Nuclear de Fukushima , Radioisótopos do Iodo/efeitos adversos , Exposição à Radiação/prevenção & controle , Relação Dose-Resposta à Radiação , Humanos , Probabilidade , Glândula Tireoide/efeitos da radiação
9.
J Air Waste Manag Assoc ; 61(10): 996-1004, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22070032

RESUMO

Based on requirements under the Clean Air Act Amendments of 1990, most state vehicle inspection and maintenance (I/M) programs have, since 2002, replaced the tailpipe emission testing with the on-board diagnostic (OBD) II testing for 1996 model and newer vehicles. This test relies on the OBD II system to give the pass or fail result, depending on certain conditions that might cause the vehicle to emit pollution 1.5 times higher than the regulated standard. The OBD II system is a computer and sensors installed in the vehicle to monitor the emission control units and signal if there is any malfunction. As a vehicle ages, its engine, pollution control units, and OBD II system deteriorate. Because the OBD II system's durability directly influences the test outcome, it is important to examine the fleetwide trend in the OBD II test results in comparison with an alternative measure of identifying high emitting vehicles. This study investigates whether the validity and reliability of the OBD II test is related to the age of the OBD II system installed in the fleet. Using Atlanta's I/M testing records and remote sensing device (RSD) data collected during 2002-2005, this research establishes the convergent validity and interobserver reliability criteria for the OBD II test based on on-road emissions measured by RSDs. The study results show that older vehicles exhibit significantly lower RSD-OBD II outcome agreement than newer vehicles. This suggests that the validity and reliability of the OBD II test may decline in the older vehicle fleets. Explanations and possible confounding factors for these findings are discussed.


Assuntos
Veículos Automotores , Emissões de Veículos/análise , Poluentes Atmosféricos/análise , Algoritmos , Monitoramento Ambiental/métodos , Falha de Equipamento , Georgia , Reprodutibilidade dos Testes
10.
Biosens Bioelectron ; 22(8): 1605-11, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16904886

RESUMO

The antimycotic agent amphotericin B (AmB) functions by forming complexes with sterols to form ion channels that cause membrane leakage. When AmB and cholesterol mixed at 2:1 ratio were incorporated into phospholipid bilayer membranes formed on the tip of patch pipettes, ion channel current fluctuations with characteristic open and closed states were observed. These channels were also functional in phospholipid membranes formed on nanoporous silicon surfaces. Electrophysiological studies of AmB-cholesterol mixtures that were incorporated into phospholipid membranes formed on the surface of nanoporous (6.5 nm pore diameter) silicon plates revealed large conductance ion channels ( approximately 300 pS) with distinct open and closed states. Currents through the AmB-cholesterol channels on nanoporous silicon surfaces can be driven by voltage applied via conventional electrical circuits or by photovoltaic electrical potential entirely generated when the nanoporous silicon surface is illuminated with a narrow laser beam. Electrical recordings made during laser illumination of AmB-cholesterol containing membrane-coated nanoporous silicon surfaces revealed very large conductance ion channels with distinct open and closed states. Our findings indicate that nanoporous silicon surfaces can serve as mediums for ion-channel-based biosensors. The photovoltaic properties of nanoporous silicon surfaces show great promise for making such biosensors addressable via optical technologies.


Assuntos
Anfotericina B/química , Técnicas Biossensoriais/métodos , Canais Iônicos/química , Lipídeos de Membrana/química , Fosfolipídeos/química , Permeabilidade da Membrana Celular , Condutividade Elétrica , Nanotecnologia , Porosidade , Silício
11.
Cells Tissues Organs ; 179(3): 115-24, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15947462

RESUMO

Unfolding and subsequent aggregation of proteins is a common phenomenon that is linked to many human disorders. Misfolded hemoglobin is generally manifested in various autoimmune, infectious and inherited diseases. We isolated micrometer and submicrometer particles, termed proteons, from human and animal blood. Proteons lack nucleic acids but contain two major polypeptide populations with homology to the hemoglobin alpha-chain. Proteons form by reversible seeded aggregation of proteins around proteon nucleating centers (PNCs). PNCs are comprised of 1- to 2-nm metallic nanoclusters containing 40-300 atoms. Each milliliter of human blood contained approximately 7 x 10(13) PNCs and approximately 3 x 10(8) proteons. Exposure of isolated blood plasma to elevated temperatures increased the number of proteons. When an aliquot of this heated plasma was introduced into untreated plasma that was subsequently heated, the number of proteons further increased, reaching a maximum after a total of three such iterations. Small concentrations of PNCs were lethal to cultured cancer cells, whereas noncancerous cells were much less affected.


Assuntos
Morte Celular/fisiologia , Proliferação de Células , Metais/sangue , Neoplasias/metabolismo , Neoplasias/patologia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cães , Glioma/química , Glioma/metabolismo , Glioma/patologia , Glioma/ultraestrutura , Hemoglobinas/metabolismo , Humanos , Masculino , Metais/isolamento & purificação , Microscopia Eletrônica de Varredura , Nanoestruturas , Neoplasias/química , Neoplasias/ultraestrutura , Coelhos , Ratos
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