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1.
Kardiologiia ; 64(4): 3-13, 2024 Apr 30.
Artigo em Russo, Inglês | MEDLINE | ID: mdl-38742510

RESUMO

AIM: Based on data from the Russian REGION-MI registry, to characterize patients with myocardial infarction (MI) hospitalized in Russian hospitals, describe their historical, demographic, and clinical characteristics, and compare the results with the data of previous Russian and international registries of acute coronary syndrome. MATERIAL AND METHODS: REGION-MI is a multicenter prospective observational study. The follow-up period was divided into three stages: during the hospital stay, at 6 and 12 months after the inclusion in the registry. Demographic and historic data and information about the present case of MI were entered into the patient's individual record card. RESULTS: The median age of all patients was 63 years; 68% of patients were men. The mean age of women was older than that of men. Among all MI cases, 70% were ST-segment elevation myocardial infarction (STEMI). Patients with non-ST-segment elevation myocardial infarction (NSTEMI) were older and had more comorbidities than patients with STEMI. The median time from the first symptoms to ECG recording was two hours, and from the first symptoms to CAG 7 hours. CAG was performed in 91% of patients with STEMI and 84% of patients with NSTEMI. Stenting was performed in 69% of patients. Although many patients had a complicated cardiovascular history, at the time of admission only 31.5% of patients were taking at least one drug from the groups of antiplatelets, oral anticoagulants, statins, and beta-blockers. CONCLUSION: Patients with MI in the Russian Federation are younger than patients with MI in European countries. Among the clinical and historical characteristics, conspicuous is the presence of modifiable risk factors in many patients, as well as the presence of a previous diagnosis of ischemic heart disease. Furthermore, a small proportion of patients took statins, antiplatelet agents or anticoagulants at the outpatient stage, which indicates a great reserve of both primary and secondary prevention of cardiovascular diseases in the Russian Federation. The delayed seeking medical help is also noticeable, which indicates the need for increasing the public awareness of the symptoms of MI and the importance of timely hospitalization.


Assuntos
Infarto do Miocárdio , Sistema de Registros , Humanos , Federação Russa/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Infarto do Miocárdio/epidemiologia , Idoso , Eletrocardiografia , Infarto do Miocárdio com Supradesnível do Segmento ST/epidemiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico
2.
Phys Rev Lett ; 131(14): 142501, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37862664

RESUMO

We present the measurement of the two-neutrino double-ß decay rate of ^{76}Ge performed with the GERDA Phase II experiment. With a subset of the entire GERDA exposure, 11.8 kg yr, the half-life of the process has been determined: T_{1/2}^{2ν}=(2.022±0.018_{stat}±0.038_{syst})×10^{21} yr. This is the most precise determination of the ^{76}Ge two-neutrino double-ß decay half-life and one of the most precise measurements of a double-ß decay process. The relevant nuclear matrix element can be extracted: M_{eff}^{2ν}=(0.101±0.001).

3.
Eur Phys J C Part Fields ; 83(9): 778, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37674593

RESUMO

We search for tri-nucleon decays of 76Ge in the dataset from the GERmanium Detector Array (GERDA) experiment. Decays that populate excited levels of the daughter nucleus above the threshold for particle emission lead to disintegration and are not considered. The ppp-, ppn-, and pnn-decays lead to 73Cu, 73Zn, and 73Ga nuclei, respectively. These nuclei are unstable and eventually proceed by the beta decay of 73Ga to 73Ge (stable). We search for the 73Ga decay exploiting the fact that it dominantly populates the 66.7 keV 73mGa state with half-life of 0.5 s. The nnn-decays of 76Ge that proceed via 73mGe are also included in our analysis. We find no signal candidate and place a limit on the sum of the decay widths of the inclusive tri-nucleon decays that corresponds to a lower lifetime limit of 1.2×1026 yr  (90% credible interval). This result improves previous limits for tri-nucleon decays by one to three orders of magnitude.

4.
Eur Phys J C Part Fields ; 83(4): 319, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122826

RESUMO

The ability to detect liquid argon scintillation light from within a densely packed high-purity germanium detector array allowed the Gerda experiment to reach an exceptionally low background rate in the search for neutrinoless double beta decay of 76 Ge. Proper modeling of the light propagation throughout the experimental setup, from any origin in the liquid argon volume to its eventual detection by the novel light read-out system, provides insight into the rejection capability and is a necessary ingredient to obtain robust background predictions. In this paper, we present a model of the Gerda liquid argon veto, as obtained by Monte Carlo simulations and constrained by calibration data, and highlight its application for background decomposition.

6.
Eur Phys J C Part Fields ; 82(4): 284, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464994

RESUMO

The GERmanium Detector Array (Gerda) collaboration searched for neutrinoless double- ß decay in 76 Ge using isotopically enriched high purity germanium detectors at the Laboratori Nazionali del Gran Sasso of INFN. After Phase I (2011-2013), the experiment benefited from several upgrades, including an additional active veto based on LAr instrumentation and a significant increase of mass by point-contact germanium detectors that improved the half-life sensitivity of Phase II (2015-2019) by an order of magnitude. At the core of the background mitigation strategy, the analysis of the time profile of individual pulses provides a powerful topological discrimination of signal-like and background-like events. Data from regular 228 Th calibrations and physics data were both considered in the evaluation of the pulse shape discrimination performance. In this work, we describe the various methods applied to the data collected in Gerda Phase II corresponding to an exposure of 103.7 kg year. These methods suppress the background by a factor of about 5 in the region of interest around Q ß ß = 2039  keV, while preserving ( 81 ± 3 ) % of the signal. In addition, an exhaustive list of parameters is provided which were used in the final data analysis.

7.
Eur Phys J C Part Fields ; 81(6): 505, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720720

RESUMO

Neutrinoless double- ß decay of 76 Ge is searched for with germanium detectors where source and detector of the decay are identical. For the success of future experiments it is important to increase the mass of the detectors. We report here on the characterization and testing of five prototype detectors manufactured in inverted coaxial (IC) geometry from material enriched to 88% in 76 Ge. IC detectors combine the large mass of the traditional semi-coaxial Ge detectors with the superior resolution and pulse shape discrimination power of point contact detectors which exhibited so far much lower mass. Their performance has been found to be satisfactory both when operated in vacuum cryostat and bare in liquid argon within the Gerda setup. The measured resolutions at the Q-value for double- ß decay of 76 Ge ( Q ß ß  = 2039 keV) are about 2.1 keV full width at half maximum in vacuum cryostat. After 18 months of operation within the ultra-low background environment of the GERmanium Detector Array (Gerda) experiment and an accumulated exposure of 8.5 kg · year, the background index after analysis cuts is measured to be 4 . 9 - 3.4 + 7.3 × 10 - 4 counts / ( keV · kg · year ) around Q ß ß . This work confirms the feasibility of IC detectors for the next-generation experiment Legend.

8.
Eur Phys J C Part Fields ; 81(8): 682, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34776783

RESUMO

The GERmanium Detector Array (Gerda) collaboration searched for neutrinoless double- ß decay in 76 Ge with an array of about 40 high-purity isotopically-enriched germanium detectors. The experimental signature of the decay is a monoenergetic signal at Q ß ß = 2039.061 ( 7 )  keV in the measured summed energy spectrum of the two emitted electrons. Both the energy reconstruction and resolution of the germanium detectors are crucial to separate a potential signal from various backgrounds, such as neutrino-accompanied double- ß decays allowed by the Standard Model. The energy resolution and stability were determined and monitored as a function of time using data from regular 228 Th calibrations. In this work, we describe the calibration process and associated data analysis of the full Gerda dataset, tailored to preserve the excellent resolution of the individual germanium detectors when combining data over several years.

9.
Phys Rev Lett ; 125(1): 011801, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32678643

RESUMO

We present the first search for bosonic superweakly interacting massive particles (super-WIMPs) as keV-scale dark matter candidates performed with the GERDA experiment. GERDA is a neutrinoless double-ß decay experiment which operates high-purity germanium detectors enriched in ^{76}Ge in an ultralow background environment at the Laboratori Nazionali del Gran Sasso (LNGS) of INFN in Italy. Searches were performed for pseudoscalar and vector particles in the mass region from 60 keV/c^{2} to 1 MeV/c^{2}. No evidence for a dark matter signal was observed, and the most stringent constraints on the couplings of super-WIMPs with masses above 120 keV/c^{2} have been set. As an example, at a mass of 150 keV/c^{2} the most stringent direct limits on the dimensionless couplings of axionlike particles and dark photons to electrons of g_{ae}<3×10^{-12} and α^{'}/α<6.5×10^{-24} at 90% credible interval, respectively, were obtained.

10.
Phys Rev Lett ; 125(25): 252502, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33416389

RESUMO

The GERmanium Detector Array (GERDA) experiment searched for the lepton-number-violating neutrinoless double-ß (0νßß) decay of ^{76}Ge, whose discovery would have far-reaching implications in cosmology and particle physics. By operating bare germanium diodes, enriched in ^{76}Ge, in an active liquid argon shield, GERDA achieved an unprecedently low background index of 5.2×10^{-4} counts/(keV kg yr) in the signal region and met the design goal to collect an exposure of 100 kg yr in a background-free regime. When combined with the result of Phase I, no signal is observed after 127.2 kg yr of total exposure. A limit on the half-life of 0νßß decay in ^{76}Ge is set at T_{1/2}>1.8×10^{26} yr at 90% C.L., which coincides with the sensitivity assuming no signal.

11.
Science ; 365(6460): 1445-1448, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31488705

RESUMO

A discovery that neutrinos are Majorana fermions would have profound implications for particle physics and cosmology. The Majorana character of neutrinos would make possible the neutrinoless double-ß (0νßß) decay, a matter-creating process without the balancing emission of antimatter. The GERDA Collaboration searches for the 0νßß decay of 76Ge by operating bare germanium detectors in an active liquid argon shield. With a total exposure of 82.4 kg⋅year, we observe no signal and derive a lower half-life limit of T 1/2 > 0.9 × 1026 years (90% C.L.). Our T 1/2 sensitivity, assuming no signal, is 1.1 × 1026 years. Combining the latter with those from other 0νßß decay searches yields a sensitivity to the effective Majorana neutrino mass of 0.07 to 0.16 electron volts.

12.
Bull Exp Biol Med ; 165(1): 36-39, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29796812

RESUMO

The direct effect of 5 mM L-NAME and 0.1 mM sodium nitroprusside on activity of lysosomal cysteine proteinases and permeability of lysosomal membrane was studied in vitro after 1, 2, and 4 h of incubation. Isolated from the liver of intact female rats lysosome suspensions were used. Both substances reduced total activity of cathepsin H and did not affect cathepsin B at all time intervals. L-NAME increased cathepsin L activity at all incubation times, while sodium nitroprusside increased activity of this enzyme after 2-h incubation and reduced it incubation after 4-h incubation. L-NAME demonstrated a membrane-destabilizing effect in in vitro experiments, while sodium nitroprusside on the contrary stabilized lysosomal membranes.


Assuntos
Cisteína Proteases/metabolismo , Membranas Intracelulares/metabolismo , Lisossomos/enzimologia , NG-Nitroarginina Metil Éster/farmacologia , Nitroprussiato/farmacologia , Animais , Permeabilidade da Membrana Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Feminino , Membranas Intracelulares/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Ratos , Ratos Wistar
13.
Klin Lab Diagn ; 62(6): 382-384, 2017.
Artigo em Russo | MEDLINE | ID: mdl-31505118

RESUMO

The effect of various concentrations of suspensions of nanoparticles of aluminum oxide of size of 30 and 70 nm on capacity of Escherichia сoli to form biofilm in vitro was examined. The study used highly virulent strain of Escherichia сoli isolated from a patient with chronic pyelonephritis. The strain was characterized by high capacity of forming biofilm. It is established that nanoparticles of aluminum oxide with size of 30 nm inhibited capacity of forming biofilm. At that, a reliable decreasing of analyzed indication in two times occurred and analyzed clones of Escherichia сoli passed to category of microorganisms with average capacity of forming biofilm. It is established that intensity of factor suppression depended both on size and concentration of nanoparticles in medium. The most effective in suppression of capacity of forming biofilm was concentration of nanoparticles of aluminum oxide 0,015 mkg/ml that decreased intensity of factor in two times.

14.
Mikrobiol Z ; 78(4): 25-33, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30653877

RESUMO

The aim of this work was to study the influence of pH of medium on antagonistic ac- tivity of isolated from authentic Hucul dairy products and gastrointestinal tract (GIT) of Hucul long-livers yeasts towards potentially harmful for humans and animals bacteria. Among 52 tested yeast isolates 14 % yeasts showed considerable antagonistic activity towards Gram-positive bacteria Staphylococcus aureus and only 6 % of them inhibited growth of Gram negative bacteria belonging to genera Escherichia and Citrobacter Most ofyeasts with antagonistic activity (over 70 %) were isolatedfriom long-livers GIT There were identifed two optimal for antagonism areas of pH values of nutrient medium for tested yeasts being around 5.5 and 6.0 for Gram-positive bacteria and around 6.0 and 6.5 for Gram negative bacteria. It appeared that isolated fiom Hucul yogurt Saccharomyces pasterianus yeasts manifested their antagonistic activity in more acidic conditions com- pared to isolates fiom GIT.


Assuntos
Antibiose , Citrobacter/crescimento & desenvolvimento , Laticínios/microbiologia , Debaryomyces/patogenicidade , Escherichia coli/crescimento & desenvolvimento , Intestinos/microbiologia , Saccharomyces/patogenicidade , Idoso de 80 Anos ou mais , Animais , Citrobacter/isolamento & purificação , Técnicas de Cocultura , Debaryomyces/isolamento & purificação , Debaryomyces/fisiologia , Escherichia coli/isolamento & purificação , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Testes de Sensibilidade Microbiana , Saccharomyces/isolamento & purificação , Saccharomyces/fisiologia , Ucrânia
15.
Mikrobiol Z ; 78(4): 82-89, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30653882

RESUMO

The aim of this work was to study the ability ofyeasts isolated from crops and dairy products to convert starch to ethanol. The isolated yeasts were screened for their ability to hydrolyze starch. Six most active strains were identified as Lipomyces mesembrius spp. 5.4, 5.5 and 6.4, Shwanniomyces vanrijiae var yarowii F33, Torulaspora sp. F7 and Candida sp. S26. The selected yeasts produced low levels of ethanol from starch under aerobic conditions - 0.006-0.129 g/l (0.3-0.87 % of theoretical yield) and microaerobic conditions - 0. 089-0.35 g/l (1.61-6.07 % of theoretical yield). These amylolytic yeast strains will be studied as the potential candidates for the cocultivation with efficient ethanol producers which do not possess the ability to directly hydrolyze starch.


Assuntos
Candida/metabolismo , Etanol/metabolismo , Lipomyces/metabolismo , Saccharomycetales/metabolismo , Amido/metabolismo , Torulaspora/metabolismo , Aerobiose/fisiologia , Candida/isolamento & purificação , Produtos Agrícolas/microbiologia , Laticínios/microbiologia , Fermentação , Hidrólise , Cinética , Lipomyces/isolamento & purificação , Saccharomycetales/isolamento & purificação , Torulaspora/isolamento & purificação
16.
Mikrobiol Z ; 78(5): 2-11, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30141858

RESUMO

The red yeasts are currently widely discussed and controversial group of yeasts because of the growing number of reports of their ability to become opportunistic pathogens of plants, animals and humans. The aim of this work was complex identifcation of the red yeast culture isolated from gastrointestinal tract of healthy Hucul long-liver from the Carpathians highland region of Ukraine. Torularhodin was found to be a major component within yeast culture carotenoids complex. According to conventional biochemical and morphological approaches as well as to molecular biological investigation of internal transcribed spacer region (ITS) of ribosomal operon it was concluded that isolate belonged to species Rhodotorula mucilaginosa.


Assuntos
Trato Gastrointestinal/microbiologia , Rhodotorula/classificação , Rhodotorula/isolamento & purificação , Carotenoides/isolamento & purificação , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Humanos , Ucrânia
17.
Mikrobiol Z ; 77(3): 9-15, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26214893

RESUMO

The aim of this work was to examine the potential of the use of one of the modern approaches in scanning electron microscopy--the wet mode ESEM to study biogeochemical processes of biominerals formation by micromycetes. The object of the study was microscopic fungus Beauveria caledonica known for its ability to transform metals and minerals. In response to the presence of copper phosphate in the medium, it was observed the abundant formation of copper oxalate crystals in fungal mycelium. Optimal visualization at wet mode was achieved at the sample chamber pressure around 6 torr and relative humidity 85 - 90%. The comparison of the observations obtained using high-vacuum mode and wet mode scanning electron microscopy showed that in their natural state fungal hyphae and mycelial cords are surrounded by thick hydrated mucilaginous sheath which serves as a matrix for biogeochemical processes of secondary minerals formation and growth. The wet mode and high-vacuum mode scanning electron microscopies complement each other in comprehensive study of biogeochemical role of microscopic fungi in transformations of metals and minerals.


Assuntos
Beauveria/ultraestrutura , Cobre/química , Microscopia Eletrônica de Varredura/métodos , Minerais/química , Micélio/ultraestrutura , Beauveria/química , Beauveria/metabolismo , Cobre/metabolismo , Umidade , Minerais/metabolismo , Micélio/química , Micélio/metabolismo , Oxalatos/química , Oxalatos/metabolismo , Fosfatos/química , Fosfatos/metabolismo , Pressão
18.
Biofizika ; 60(2): 371-6, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26016035

RESUMO

Antitumor activity of the novel for oncology compound, such as polysuccinimide, against some of experimental tumor models (Lewis lung carcinoma, Acatol adenocarcinoma, Ca-755 adenocarcinoma) has been established. This drug induced 60-80% tumor growth inhibition of these murine solid tumor strains. Polysuccinimide is also effective (60%) against development of metastatic process in lung (Lewis lung carcinoma). Polysuccinimide causes no changes in pH level in tumor tissue (P-388 leukemia, Acatol adenocarcinoma). This agent may be recommended for further profound preclinical study.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/administração & dosagem , Ácido Aspártico/análogos & derivados , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Peptídeos/administração & dosagem , Adenocarcinoma/patologia , Animais , Ácido Aspártico/administração & dosagem , Ácido Aspártico/síntese química , Carcinoma Pulmonar de Lewis/patologia , Humanos , Camundongos , Peptídeos/síntese química
19.
Biofizika ; 60(1): 152-7, 2015.
Artigo em Russo | MEDLINE | ID: mdl-25868353

RESUMO

The inhibitory action of binuclear dinitrosyl iron complexes with glutathione on the growth of implanted solid tumor in BDF1 mice bearing Lewis lung carcinoma cells was found. The effect was induced by intraperitoneal injection of the binuclear dinitrosyl iron complexes to mice at a dose of 200 µM/kg daily on days 1-5 and 7-11. At the binuclear dinitrosyl iron complexes: free glutathione ratios of 1:1; and 1:10 in solutions, the inhibitory effect of the DNICs reached the level of 70% and 85%, respectively. When B-DNICs were not further infused, intensive tumor growth, a more rapid rate of tumor growth than control, was observed. The selective accumulation of DNICs as well as iron nitrosyl complexes of heme-containing proteins in tumors were detected by EPR method. The latter were found also in the tumors in control animals. Tumor growth delay in course of B-DNIC administration to the mice is supposed to be due to the elaboration of anti-nitrosative defense in tumor tissue in response to the action of NO released from B-DNIC.


Assuntos
Carcinoma Pulmonar de Lewis/metabolismo , Citotoxinas/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ferro/farmacologia , Óxido Nítrico/farmacologia , Óxidos de Nitrogênio/farmacologia , Animais , Carcinoma Pulmonar de Lewis/patologia , Feminino , Camundongos
20.
Angiol Sosud Khir ; 21(1): 29-34, 2015.
Artigo em Russo | MEDLINE | ID: mdl-25757163

RESUMO

The objects of the study were a total of 24 conventional sexually mature Wistar rats weighing 200-400 g. Thrombosis was modelled by means of ligation of the common iliac vein. Animals were withdrawn from the study on days 1, 3 and 5 after intervention. The materials for the study in each animal were homogenates of the vein portion below the site of ligation (thrombosed vein) and the portion of the symmetrical vessel (intact vein). Taken as controls were portions of the common iliac vein of intact animals matched by age, body weight, and keeping conditions. The level of spontaneous and induced in the Fenton reaction oxidative carbonylation of proteins was determined by means of carbonyl derivatives according to the R.L. Levine technique modified by E.E. Dubinina with optical registration of the formed dinitrophenylhydrazines at 356, 370, 430 and 530 nm. The reserve-and-adaptation potential was assessed by means of counting the ratio of the amount of carbonyl derivatives of proteins in spontaneous and induced oxidation. The obtained findings showed that experimental thrombosis is accompanied and followed by an increase in the content of carbonyl derivatives of proteins in the wall of thrombosed veins and, to a lesser degree, in that of intact veins. The maximal elevation of the parameters was registered during the first 24 hours of the development of pathology, demonstrating not only early but late markers of oxidative modification of proteins. Thrombosed veins on day 3 were found to have a decrease in the content of carbonylated proteins to the level of the control values, which was associated with a maximal value of the reserve-adaptation potential. However, day five was marked by a secondary increase in carbonylation accompanied by certain exhaustion of the reserve-adaptive potential. In intact veins, a decrease of the spontaneous oxidative modification level on day 3 was accompanied by a splash of induced carbonylation followed by stabilization of the parameters at the levels slightly exceeding the control values by day 5.


Assuntos
Endotélio Vascular/metabolismo , Estresse Oxidativo/fisiologia , Carbonilação Proteica/fisiologia , Proteínas/metabolismo , Veia Cava Inferior/metabolismo , Trombose Venosa/metabolismo , Animais , Modelos Animais de Doenças , Progressão da Doença , Feminino , Seguimentos , Ratos , Ratos Wistar , Veia Cava Inferior/patologia
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