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1.
Sud Med Ekspert ; 66(6): 9-12, 2023.
Artigo em Russo | MEDLINE | ID: mdl-38093422

RESUMO

The article presents the experimental study results of damaged clothes imitators' (coarse calico) features in consequence of shot by ammunitions with hollow-point bullet from a 12-gauge fire smoothbore weapon (12×70). The generation mechanism of coarse calico damage during wound of underlying biological human body's imitator by bullet and the factors influencing on mentioned process have been clarified using high-speed video recording.


Assuntos
Armas de Fogo , Ferimentos por Arma de Fogo , Humanos , Ferimentos por Arma de Fogo/etiologia , Balística Forense/métodos , Armas
2.
Rev Sci Instrum ; 92(12): 124704, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34972453

RESUMO

The results of the concept development of the universal high-voltage power supply with the output parameters providing the reliable operation of compact THz vacuum electron devices have been presented and discussed. The low-level of high-voltage ripples less than 10 ppm at 6 kV, 250 mA was obtained with the help of the designed high-precision and fast-response stabilization scheme. Real-time stabilization of the output parameters of vacuum electron devices was realized by using the multiloop proportional-integral-differential feedback control and was tested with the continuous-wave clinotron tubes in millimeter range. The developed high-voltage power supply offers the high-voltage modulation mode that allows applying the THz tubes with electronic frequency tuning for frequency-modulated continuous wave radar applications.

3.
Sud Med Ekspert ; 56(4): 11-5, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24428050

RESUMO

We have developed the criteria allowing to determine the distance of a gunshot from limited-range firearms (an IZh-79-9TGM pistol with the elastic bullet cartridges) based on the morphological characteristics of the wound and the results of inductively coupled plasma mass spectrometry. The method has been developed for the quantitative determination of barium, lead, and antimony in the targets depending on the gunshot distance.


Assuntos
Armas de Fogo , Balística Forense/métodos , Ferimentos por Arma de Fogo , Humanos , Espectrometria de Massas/métodos , Pesos e Medidas , Ferimentos por Arma de Fogo/etiologia , Ferimentos por Arma de Fogo/patologia
6.
Mikrobiologiia ; 73(1): 73-9, 2004.
Artigo em Russo | MEDLINE | ID: mdl-15074044

RESUMO

This work deals with a comparative analysis of Stachybotrys chartarum strains isolated from various artificial cellulose-containing materials and natural substrates in the geographically distant regions of Russia. The analysis included the determination of the spore size, the strain toxicity to Paramecium caudatum, the strain resistance to the fungicides Benomil, Olilen, and Tilt, and the PCR study of the genome structure with the aid of a primer that was complementary to the core sequence of the SINE retrotransposon. It was found that some of the strains that were isolated from different areas and from different substrates differ in their toxicity, fungicide resistance, and genome structure. The PCR analysis showed the absence of any correlation between the genome structure, the strain properties, the geographic area, and the substrates from which the strains were isolated. The pheno- and genotypic diversity of the strains and their different vegetative compatibility suggest the existence of an intraspecies diversity of the S. chartarum strains that were isolated in different geographic areas. The absence of any correlation between the pheno- and genotypic properties of the strains and the substrates from which they were isolated implies that the colonization of artificial substrates by S. chartarum occurred occasionally from natural habitats. The S. chartarum populations that live on artificial substrates are unlikely to have their own evolutionary history.


Assuntos
Microbiologia Ambiental , Stachybotrys/fisiologia , Animais , Fungicidas Industriais/farmacologia , Genoma Bacteriano , Paramecium/microbiologia , Federação Russa , Especificidade da Espécie , Esporos Fúngicos , Stachybotrys/efeitos dos fármacos , Stachybotrys/isolamento & purificação
8.
Vopr Onkol ; 44(1): 60-4, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9578733

RESUMO

Benz(a)pyrene pollution levels have been identified in the soils and vegetation of the flood plains of the River Luga, Leningrad Region. Maximum pollution exceeding background levels 2-10 times (11.02-52.71 mkg/kg) was detected in the soils around the towns of Luga and Kingisepp. The benz(a)pyrene levels in the vegetation (2.04 mkg/kg) were below background values. No significant correlation was established between the concentrations of pollution in the soil and vegetation. Our data suggest that the area of the mid-course of the River Luga should be preserved as a natural habitat of the plants of the Poaceae family.


Assuntos
Benzo(a)pireno/análise , Poluentes Ambientais/análise , Plantas , Solo , Poluição Ambiental , Plantas/química , Federação Russa
9.
Pharmacogenetics ; 8(2): 109-18, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10022748

RESUMO

Levels of anti-benzo[a]pyrene diol-epoxide DNA adducts were analysed by high-pressure liquid chromatography/fluorimetric detection in non-tumorous lung tissues from 20 lung cancer patients and in white blood cells from 20 polycyclic aromatic hydrocarbon exposed coke oven workers. All were current tobacco smokers. CYP1A1 mutations (MspI at 6235 nt, Ile-Val462) and GSTM1 deletion polymorphisms in each individual were analysed in genomic DNA by PCR/restriction fragment length polymorphism. Independently of the CYP1A1 genotype (1) all 23 samples in the two groups with non-detectable adducts (< 0.2 per 10(8) nt) were of GSTM1 active genotype; (2) the 17 samples with detectable adducts (> or = 0.2 per 10(8) nt) in the two groups were GSTM1*0/*0. The difference in adduct levels between GSTM1*0/*0 and GSTM1 active genotype was highly significant (p < 0.00005). Among GSTM1-deficient individuals (n = 17), a subgroup of 14 individuals with CYP1A1*1/*1 (wild-type, n = 7) or heterozygous genotype (*1/*2A or *1/*2B, n = 7) showed low levels of BPDE DNA-adducts (range: 0.2-1.3 per 10(8) nt). (3) Three individuals with the rare combination CYP1A1*2A/*2A or *2A/*B and GSTM1*0/*0 showed significantly higher adduct levels (median: 17.4 adducts/10(8) nt, range 1.9-44; p = 0.017). Therefore, combination of homozygous mutated CYP1A1 and GSTM1*0/*0 genotypes lead, at a similar or even lower smoking dose, to a stronger increase of anti-benzo[a]pyrene diol-epoxide DNA adduct levels than found in individuals with CYP1A1 and GSTM1 wild-type. These data provide a mechanistic understanding of epidemiological studies that correlated these 'at risk' genotypes with increased smoking-related lung cancers.


Assuntos
7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/metabolismo , Citocromo P-450 CYP1A1/genética , Adutos de DNA/metabolismo , Glutationa Transferase/genética , Leucócitos/metabolismo , Pulmão/metabolismo , Adulto , Idoso , Desoxirribonuclease HpaII , Feminino , Genótipo , Heterozigoto , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Reação em Cadeia da Polimerase , Fumar
12.
Vopr Onkol ; 42(5): 76-9, 1996.
Artigo em Russo | MEDLINE | ID: mdl-9064910

RESUMO

Fjord-region polycyclic aromatic hydrocarbon (PAH) dibenz (a,l)pyrene (DBP) is the most potent carcinogen in the PAH group. To elucidate the molecular mechanism of the unusual carcinogenic potency of DBP, the levels of DNA adducts in various tissues of the mouse were measured, following an intraperitoneal administration of DBP or a bay-region PAH benz(a)pyrene (BP) in equimolar doses. DBP was found to form much more DNA adducts. While BP formed adducts via fjord-region diol-epoxide formation only, DBP did the same via formation, too. It is suggested that the superior carcinogenic potency of DBP is due to these peculiarities of DNA adduct formation.


Assuntos
Benzo(a)pireno/química , Benzopirenos/química , Carcinógenos/química , Animais , Adutos de DNA/química , Masculino , Camundongos , Camundongos Pelados
13.
Biomarkers ; 1(4): 244-51, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-23888991

RESUMO

Abstract Urinary 3-methyladenine (3-MeAde) excretion andlymphocyte DNA adduct formation was studied in 15 patients receiving methylnitrosourea (MNU) at several dose levels (250 mg, 300 mg and600 mg total dose, 143-385 mg m(-2)) as part of various combination chemotherapies for advanced tumours (malignant melanoma, lymphoblastic lymphosarcorna andHodgkin's disease). Urinary 3-MeAde levels were significantly increased over background in patients at all dose levels (p < 0.001) andthe increases were dose-dependent (r = 0.77, p < 0.01). There were large interindividual variations in the excretion of 3-MeAde at each dose of MNU. In a subset of patients, N7-methyl-2-deoxyguanosine (7-MedG) andO(6)-methyl-2'-deoxyguanosine (O(6)-WedG) levels in DNA from blood leucocytes showed dose-dependent increases, however there were no simple relationships between urinary methylated DNA bases andleucocyte DNA adducts. Levels of adducts in leucocyte DNA (7-MedG, < 17-217 µmol mol(-1) dG; O(6)-WedG, < 1.6-35 µmol mol(-1) dG) were comparable with those reported for other methylating chemotherapeutic drugs. Leucocyte DNA andurinary methyl adducts may be useful markers of individual responses to treatment with methylating drugs.

15.
Cancer Lett ; 78(1-3): 163-70, 1994 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8180958

RESUMO

In white outbred LIO rats exposed to multiple intraperitoneal (i.p.) doses (10 mg/kg) of benzo[a]pyrene (BP) in the form of a water-lipid emulsion, individual peculiarities of the excretion of its metabolites, BP-7,8-diol and 3-hydroxy-BP (3-OH-BP) in urine and feces were detected and compared with the carcinogenic effect. Parameters of BP metabolite excretion differed from those found in our previous experiments with rats exposed to single high i.p. doses of BP (100 and 200 mg/kg), dissolved in sunflower oil [11,12]. In comparison with our previous observation, in the present study, the carcinogenic effect was considerably weaker (5/22 versus 10/19). The rats that developed tumours of internal tissues (four peritoneal malignant histiocytomas and one lung lymphosarcoma), excreted higher quantities of BP-7,8-diol in the urine than other rats. The possible implication of monitoring excretion of BP metabolites for predicting individual susceptibility to its carcinogenic effect is discussed.


Assuntos
Benzo(a)pireno/metabolismo , Neoplasias Experimentais/induzido quimicamente , Animais , Benzo(a)pireno/análogos & derivados , Masculino , Neoplasias Experimentais/urina , Ratos , Fatores de Tempo
16.
Mol Biol (Mosk) ; 28(1): 167-71, 1994.
Artigo em Russo | MEDLINE | ID: mdl-8145745

RESUMO

Thermal properties of DNA-benz(a)pyrene complex and chromatin within liver cells in BALB/c mice and Macaca fascicularis monkeys after benz(a)pyrene administration were studied using a highly sensitive differential scanning microcalorimeter designed for investigations of dilute biopolymer solutions and complex biological systems. It was shown that benz(a)pyrene (BP) had different efforts on DNA in vivo and in vitro. It was established that at a molar ratio r < 0.03 BP/DNA bp, benz(a)pyrene served as a stabilizing but at higher concentrations as a destabilizing factor of DNA. It was found that BP damaged liver DNA stronger than bone marrow and spleen DNA of a given animal in vivo. Based on analysis of heat redistribution at the heat absorption stages corresponding to denaturation of inactive and active chromatin, we concluded that BP is capable of causing specific breaks in the DNA chain of inactive chromatin and unfolding the whole domain-loop of chromatin, which should lead to uncontrolled genome activation and, therefore, to carcinogenesis.


Assuntos
Benzo(a)pireno/farmacologia , DNA/efeitos dos fármacos , Animais , Varredura Diferencial de Calorimetria , Bovinos , Cromatina/metabolismo , Temperatura Alta , Fígado/metabolismo , Macaca fascicularis , Camundongos , Camundongos Endogâmicos BALB C , Desnaturação Proteica
17.
Int J Cancer ; 54(5): 728-33, 1993 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-8325702

RESUMO

The levels of 3 DNA repair enzymes involved in alkylation and oxidative DNA damage repair in human peripheral blood leukocytes were measured in 20 smokers and 17 non-smokers. No differences in O6-alkylguanine-DNA-alkyltransferase (AGT) activity were found between the 2 groups and the AGT distribution within the population appeared to be unimodal. In contrast, the mean activities of both the methylpurine (MeP)- and the 2-6-diamino-4-hydroxy-5N formamidopyrimidine (FaPy)-DNA glycosylases were higher in the smokers, although only the difference between the MeP-DNA glycosylase means was statistically significant. The standard deviations of these 2 enzymes were also higher in the smokers. The MeP-DNA glycosylase activity showed a bimodal distribution when all subjects were considered. This may in part be due to the smoking habit; 83% of the subjects with enzyme activities higher than 500 fmoles/mg protein were current smokers, whilst 85% of the non-smokers had lower enzyme activities. However, if the smokers were considered separately, a bimodal distribution of this enzyme activity could still be observed. No strong correlation was observed between enzyme activity and age, although the slopes of the regression lines of enzyme activity on age were all negative. The relationship between enzyme activities was studied by bivariate distribution and a strong correlation was only found between the MeP-DNA glycosylase and the FaPy-glycosylase, with the highest values of both enzyme activities being observed in the smokers and the lowest in the non-smokers. Our results suggest that the activity of certain DNA repair enzymes can be modulated by environmental exposure.


Assuntos
Dano ao DNA , DNA Ligases/sangue , Reparo do DNA , Leucócitos , Fumar/sangue , Adulto , Fatores Etários , Alquilação , Humanos , Leucócitos/enzimologia , Masculino , Oxirredução
18.
Biochimie ; 75(9): 821-4, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8274534

RESUMO

The activity of a DNA repair enzyme, O6-alkylguanine-DNA alkyltransferase (AGT), was studied in gastric mucosa of 15 Macaca fascicularis monkeys before and during chronic oral exposure to the ethylating carcinogen N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) in order to investigate possible causes of inter-individual differences in susceptibility to its gastrocarcinogenic effect. A wide range of AGT activity (307-1903 fmol/mg protein, mean 695) was found before treatment and it decreased during the first year of exposure (means 627, 479 and 452 fmol/mg protein respectively at 6, 12 and 18 months after the beginning of the experiment). The carcinogenesis study is under way and to date four monkeys with low initial AGT level in gastric mucosa died of gastric cancer. The relevance of AGT level measurement for prediction of individual susceptibility to ENNG is discussed.


Assuntos
Carcinógenos/toxicidade , Mucosa Gástrica/efeitos dos fármacos , Metilnitronitrosoguanidina/análogos & derivados , Metiltransferases/metabolismo , Administração Oral , Animais , Carcinógenos/administração & dosagem , Feminino , Mucosa Gástrica/enzimologia , Macaca fascicularis , Masculino , Metilnitronitrosoguanidina/administração & dosagem , Metilnitronitrosoguanidina/toxicidade , O(6)-Metilguanina-DNA Metiltransferase , Neoplasias Gástricas/induzido quimicamente
19.
Vopr Onkol ; 39(4-6): 189-92, 1993.
Artigo em Russo | MEDLINE | ID: mdl-7975394

RESUMO

The study involved two groups of patients aged 6-14 and 40-60 years, and identification of different conditions of gastric mucosa. The study has established a correlation between the nitrosation activity and acidity of gastric juice and the pathological condition of the gastric mucosa. Enhanced nitrosation activity was observed in samples with a pH under 4.0. That activity was at its lowest in cases of normal gastric mucosa, and at its peak--in high-acidity superficial and erosive gastritis. In cases of superficial gastritis with similar levels of acidity, the nitrosation activity of gastric juice for different amines in children was 2-4 times that in adults. The difference in nitrosation levels for different amines tended to diminish with the decrease in the basicity of the amine in question. A linear correlation was observed between the free-radical activity of gastric juice samples and nitrosation activity (correlation coefficient, k = 0.72).


Assuntos
Envelhecimento/metabolismo , Suco Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Gastropatias/metabolismo , Adolescente , Adulto , Criança , Dimetilaminas/farmacocinética , Radicais Livres , Determinação da Acidez Gástrica , Humanos , Concentração de Íons de Hidrogênio , Pessoa de Meia-Idade , Nitrosação , Nitrito de Sódio/farmacocinética
20.
Int Arch Occup Environ Health ; 65(1 Suppl): S155-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8406916

RESUMO

In order to develop new markers of individual susceptibility to various human carcinogens, we studied some parameters of formation and metabolism of carcinogens, as well as DNA adducts formation and DNA repair in animals and humans. Following an i.p. administration of benzo(a)pyrene (BP) to the rats, levels of urinary excretion of BP-7,8-diol correlated with tumour latency. A high correlation was found between excretion of this metabolite and BP-DNA adducts level in the liver. Healthy smokers excreted higher quantities of BP-7,8-diol, than smoking lung cancer patients, thus confirming the suggestion on existence of cancer-prone phenotype. N-nitroso compounds formed most efficiently in stomach juice of children with superficial gastritis who therefore could be at high risk of stomach cancer. N-ethyl-N'-nitro-N-nitrosoguanidine induced stomach cancer earlier in monkeys with a low level of DNA repair enzyme, O6-alkylguanine-DNA alkyltransferase (AGT) in gastric mucosa. Overall, these markers can be helpful in predicting individual susceptibility to carcinogens.


Assuntos
Benzo(a)pireno/metabolismo , Biomarcadores/análise , Carcinógenos/análise , Suscetibilidade a Doenças , Monitoramento Ambiental/métodos , Compostos Nitrosos/metabolismo , Adulto , Fatores Etários , Animais , Benzo(a)pireno/efeitos adversos , Benzopirenos/análise , Criança , DNA/metabolismo , Reparo do DNA , Di-Hidroxi-Di-Hidrobenzopirenos/análise , Feminino , Suco Gástrico/metabolismo , Mucosa Gástrica/enzimologia , Gastrite/metabolismo , Humanos , Neoplasias Pulmonares/etiologia , Macaca fascicularis , Masculino , Metiltransferases/metabolismo , Pessoa de Meia-Idade , Compostos Nitrosos/efeitos adversos , O(6)-Metilguanina-DNA Metiltransferase , Ratos , Fumar/metabolismo , Neoplasias Gástricas/etiologia
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