RESUMEN
The genotyping of 75 trees from poplar plantations in St. Petersburg and Leningrad oblast was conducted with microsatellite markers to identify the elite clonal varieties developed by P.L. Bogdanov in the period of 19381965. The information about the varieties was lost. The authentic herbarium specimens of poplar clonal varieties preserved at the St. Petersburg State Forest Technical University were used as reference genotypes. According to the results of DNA fingerprinting, we identified the clonal plantations of Populus × newesis Bogd. and Populus × leningradensis Bogd. from the Kartashevskii forest district and the arboretum of the St. Petersburg State Forest Technical University. The identified elite poplar hybrids have a higher frost resistant and a higher growth rate. They are recommended for plantation cultivation in the northwest of Russia.
Asunto(s)
Aclimatación , Genotipo , Repeticiones de Microsatélite , Fitomejoramiento , Populus/genética , Técnicas de Genotipaje , Populus/crecimiento & desarrolloRESUMEN
There are two types of intrinsic surface states in solids. The first type is formed on the surface of topological insulators. Recently, transport of massless Dirac fermions in the band of "topological" states has been demonstrated. States of the second type were predicted by Tamm and Shockley long ago. They do not have a topological background and are therefore strongly dependent on the properties of the surface. We study the problem of the conductivity of Tamm-Shockley edge states through direct transport experiments. Aharonov-Bohm magneto-oscillations of resistance are found on graphene samples that contain a single nanohole. The effect is explained by the conductivity of the massless Dirac fermions in the edge states cycling around the nanohole. The results demonstrate the deep connection between topological and non-topological edge states in 2D systems of massless Dirac fermions.
RESUMEN
The main goal of a dividing cell is to distribute its genetic material equally between two daughter cells. Each of the two sister chromatids comprising each chromosome should go into one of the daughter cells. This is possible thanks to polar protein polymers called microtubules, which form a structure called "spindle" during mitosis. Microtubules are one of the basic elements of the cytoskeleton, but at the same time they are highly dynamic. Minus ends of the microtubules attach to the two poles of the spindle, while their plus ends are constantly growing or shrinking, and are also able to attach to the chromosomes and to move them. Chromosomes attach to the microtubule ends with a special protein super-complex called kinetochore. Each sister chromatid in a pair attaches to the microtubules emanating from a corresponding spindle pole. Kinetochores are attached to the dynamic plus ends of the microtubules, but tubulin subunits are still able to attach and detach to these attached ends. One of the most important questions in mitosis is understanding of the mechanism that allows such attachment to be stable (since unstable attachments lead to chromosome loss and aneuploidy) yet dynamic (arrest of the microtubule dynamics stops mitosis). More than 100 proteins comprising the kinetochore are known today, but there is no clear mechanical view on the molecular machine that forms kinetochore-microtubule attachment. The difficulties in understanding this mechanism are due to the variety of theoretical views on the principle of such machine, as well as limited number of biochemically isolated candidates to test these hypotheses experimentally. Therefore, investigation of the properties of putative couplers of microtubule depolymerization and chromosome movement is an important task.
Asunto(s)
Cinetocoros/metabolismo , Microtúbulos , Mitosis , Proteínas Nucleares , Cromátides/metabolismo , Cromátides/ultraestructura , Segregación Cromosómica/genética , Cromosomas/genética , Cromosomas/ultraestructura , Microtúbulos/genética , Microtúbulos/metabolismo , Microtúbulos/ultraestructura , Mitosis/genética , Mitosis/fisiología , Movimiento , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismoRESUMEN
The epizootic etiologically associated with highly pathogenic avian influenza H5N1 genotype 2.3.2 that is new for Russia among wild and domestic birds in the south of the Primorye Territory during spring migration in April 2008 has been decoded. About 25% of the wild birds of a water complex, which include European teals (Anas crecca), mallard ducks (Anas platyrhynchos), great-crested grebes (Podiceps cristatus), are involved in viral circulation in the area of the Suifun-Khankai plain. Chicken embryos and the cell lines MDCK, SPEV, BHK-21, SW-13 were used to isolate 3 strains from recently deceased hens (A/chicken/Primorje/1/08, A/chicken/Primorje/11/08, and A/chicken/Primorje/12/08) and one strain from a European teal (A/Anas crecca/Primorje/8/08). The strains were deposited in the State Collection of Viruses of the Russian Federation, D. I. Ivanovsky Research Institute of Virology, Russian Academy of Medical Sciences. The nucleotide sequences of the full-sized genomes of A/chicken/Primorje/1/08 and A/Anas crecca/Primorje/8/08 were sent to the International databank GenBank. The strains from domestic and wild birds were shown to be identical. The isolated strains are most close to the strains Alchicken/Viet Nam/10/05, A/chicken/Guangdong/178/04, and A/duck/Viet Nam/12/05. Molecular genetic analysis has indicated that the strains isolated are susceptible to rimantadine and ozeltamivir and less adapted to mammalian cells (particularly, they contain E627 in RV2, which agrees with the biological properties of these strains in vitro). Penetration of the newly isolated virus into the Far East ecosystem provides in the foreseeable future a way for infecting the birds wintering in America and Australia in the nesting places, with further carriage of viral populations there in the period of autumn migrations.
Asunto(s)
Brotes de Enfermedades , Subtipo H5N1 del Virus de la Influenza A/clasificación , Subtipo H5N1 del Virus de la Influenza A/genética , Gripe Aviar/epidemiología , Gripe Aviar/virología , Migración Animal , Animales , Antivirales/farmacología , Aves/virología , Pollos/virología , Genoma Viral , Genotipo , Subtipo H5N1 del Virus de la Influenza A/efectos de los fármacos , Subtipo H5N1 del Virus de la Influenza A/aislamiento & purificación , Datos de Secuencia Molecular , Oseltamivir/farmacología , Filogenia , Rimantadina/farmacología , Siberia/epidemiologíaRESUMEN
Mitotic chromosomes segregate at the ends of shortening spindle microtubules (MTs). In budding yeast, the Dam1 multiprotein complex supports this dynamic attachment, thereby contributing to accurate chromosome segregation. Purified Dam1 will track the end of a depolymerizing MT and can couple it to microbead transport in vitro. The processivity of such motions has been thought to depend on rings that the Dam1 complex can form around MTs, but the possibility that alternative coupling geometries contribute to these motilities has not been considered. Here, we demonstrate that both rings and nonencircling Dam1 oligomers can track MT ends and enable processive cargo movement in vitro. The coupling properties of these two assemblies are, however, quite different, so each may make a distinct contribution to chromosome motility.
Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Animales , Transporte Biológico , Polaridad Celular , Chlamydomonas , Difusión , Microesferas , Peso Molecular , Estructura Cuaternaria de Proteína , Subunidades de Proteína/metabolismo , Saccharomyces cerevisiae/citología , Solubilidad , Soluciones , TetrahymenaRESUMEN
The paper presents the results of monitoring of viruses of Western Nile (WN), Japanese encephalitis (JE), tick-borne encephalitis (TBE), Geta, Influenza A, as well as avian paramicroviruses type I (virus of Newcastle disease (ND)) and type 6 (APMV-6) in the Primorye Territory in 2003-2006. Totally throughout the period, specific antibodies to the viruses were detected by neutralization test in wild birds (7.3%, WN; 8.0%, Geta; 0.7% Batai; 2.8%, Alpine hare (Lepus timidus); by hemagglutination-inhibition test in cattle (11.4% WN; 5.9%, JE; j 3.0%, TBE; 11.6%, Geta), horses (6.1, 6.8, 0, and 25.3%, respectively), and pigs (5.4, 1.5, 0, and 5.9%, respectively) by enzyme immunoassay (IgG) in human beings (0.8, 0.5, 6.8, and 3.2%, respectively. Reverse-transcription polymerase chain reaction (RT-PCR) was used to reveal RNA of the NP segment of influenza A virus in 57.9 and 65% of the cloacal swabs from wild and domestic birds, respectively; and the HA-segment of subtype HH was not detected in 2005. HA/H5 RNA was recorded in 5.5 and 6.7% of the swabs from wild and domestic birds, respectively; 6% of the specimens from domestic birds were M-segment positive in 2006. RNA of influenza A virus NA/H7 and RNA was not detected throughout the years. In 2004, the cloacal swabs 8 isolated influenza A strains: two H3N8 and two H4N8 strains from European teals (Anas crecca), two (H3N8 and H6N2) strains from Baikal teals (A. formosa), one (H10N4) strain from shovelers (A. clypeata), and one (H4N8) from garganeys (A. querquedula). In 2004, one ND virus strain was isolated from the cloacal swabs from European teals (A. crecca). RT-PCR revealed RNA of this virus in some 8 more cloacal swabs from black ducks (A. poecilorhyncha) (3 positive specimens), pheasants (Phasianus colchicus) (n = 2), garganeys (A. querquedula) (n = 1), gadwalls (A. strepera) (n = 1), and geese (Anser anser domesticus) (n = 1). Sequencing of the 374-member fragment of the ND virus F gene, which included a proteolytic cleavage site, could assign two samples to the weakly pathogenetic variants of genotype 1, one sample to highly pathogenic variants of genotype 3a, five to highly pathogenic ones of genotype 5b. Isolation of APMV-6 (2003) from common egrets (Egretta alba) and geese (Ans. anser domesticus) is first described.
Asunto(s)
Infecciones por Alphavirus/epidemiología , Alphavirus/inmunología , Infecciones por Bunyaviridae/epidemiología , Monitoreo del Ambiente , Infecciones por Flavivirus/epidemiología , Flavivirus/inmunología , Virus de la Influenza A/inmunología , Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/epidemiología , Enfermedad de Newcastle/epidemiología , Virus de la Enfermedad de Newcastle/inmunología , Virus de la Enfermedad de Newcastle/aislamiento & purificación , Animales , Animales Recién Nacidos , Anticuerpos Antivirales/sangre , Aves , Virus Bunyamwera/inmunología , Bovinos , Línea Celular , Embrión de Pollo , Monitoreo Epidemiológico , Pruebas de Inhibición de Hemaglutinación , Humanos , Técnicas para Inmunoenzimas , Virus de la Influenza A/genética , Gripe Aviar/sangre , Gripe Aviar/virología , Mamíferos , Ratones , Pruebas de Neutralización , Enfermedad de Newcastle/virología , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estudios Seroepidemiológicos , Siberia/epidemiología , PorcinosRESUMEN
Repeated epidemiological studies of atherosclerosis were performed in 1985-1989 (as compared to 1965-1968) in 20-59-year-old males of malme, praha, Tallinn, Yalta and in 40-59-year-old females in Malme, Riga and Yalta. 358 cases of diabetes mellitus (DM) were studied. DM occurred more frequently during the second interval as compared to the first one: 6.3 and 4.6% in males, and 7.6 and 4.2% in females, respectively. The severity of atherosclerosis (aorta and coronary arteries were studied morphometrically after staining with Sudan IV) was higher in patients with DM the influence of which was similar to that of the arterial hypertension. The severity of atherosclerosis in DM depended, to a certain degree, on atherosclerosis level in the population. There was a trend to a decrease of atherosclerosis severity within the second interval in Malme and Praha, and its increase in Riga, Tallinn and Yalta. There was no significant difference in atherosclerosis severity that would depend on DM severity and regularity of its treatment.
Asunto(s)
Arteriosclerosis/epidemiología , Angiopatías Diabéticas/epidemiología , Adulto , Enfermedades de la Aorta/complicaciones , Enfermedades de la Aorta/epidemiología , Arteriosclerosis/complicaciones , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/epidemiología , Estudios Transversales , Checoslovaquia/epidemiología , Femenino , Finlandia/epidemiología , Humanos , Letonia/epidemiología , Masculino , Persona de Mediana Edad , Federación de Rusia/epidemiología , Suecia/epidemiologíaRESUMEN
Repeated study of atherosclerosis epidemiology is performed in 5 European cities (Malme, Prague, Riga, Tallinn, Yalta) according to WHO recommendations 20 years after a similar study in the same regions. More frequent and more pronounced development of atherosclerosis in males of 20-39 years of age is found in the present study in 3 big cities (Prague, Riga, Tallinn) as compared to the population of small cities Malme and Yalta. The rejuvenation of atherosclerosis can not be explained by an ecological situation as in females atherosclerosis was most pronounced in Malme. Possible reasons of the evolution of atherosclerosis is discussed.
Asunto(s)
Enfermedades de la Aorta/epidemiología , Enfermedad de la Arteria Coronaria/epidemiología , Adulto , Aorta Abdominal , Aorta Torácica , Checoslovaquia/epidemiología , Estonia/epidemiología , Femenino , Humanos , Letonia/epidemiología , Masculino , Persona de Mediana Edad , Distribución por Sexo , Suecia/epidemiología , Ucrania/epidemiología , Organización Mundial de la SaludRESUMEN
The trends in atherosclerosis presentation were followed up pathomorphologically in a two-stage epidemiological survey performed in 9 cities of CIC and Baltic states at 25-year interval. The investigations were conducted in accordance with WHO program. Stage 1 (1963-1968) covered 6121 cases, stage 2 (1985-1989) included 9201 cases. The material was collected on the condition of aortas and coronary arteries from 20-59-year-old males who were residents of the cities of Irkutsk, Yakutsk, Tallin, Tartu, Riga, Kharkov, Yalta, Ashkhabad, Bishkek. The 2-stage examinations gave evidence for growing severity of atherosclerosis. Risk factor analysis demonstrated an increase in the percentage of males with diabetes mellitus and arterial hypertension, in the percentage of overweight males and of those with atherosclerosis engaged in mental work. It is found that atherosclerosis undergoes changes within the life of one generation (for 20-25 years).
Asunto(s)
Arteriosclerosis/epidemiología , Población Urbana/estadística & datos numéricos , Adulto , Enfermedades de la Aorta/epidemiología , Enfermedades de la Aorta/patología , Arteriosclerosis/patología , Países Bálticos/epidemiología , Comunidad de Estados Independientes/epidemiología , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/patología , Progresión de la Enfermedad , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
1447 autopsies (87% of all deaths in the region) of males at the age from 20 to 59 years were analysed regardless of the cause of death. The first place among the causes of death belongs to the coronary heart disease and cerebrovascular pathology--31.7%. The prevalence of the arterial hypertension in the population was 14.2%, hypercholesterolemia --17.6%, smoking--82.7%, excess of body weight--8.6%, increased thickness of subcutaneous fat--39.4%, low physical activity--40%, diabetes mellitus--3%. The death from cardiovascular diseases among persons with hypertension was considerably more frequent that among persons with normal pressure. Systolic and diastolic arterial pressure was significantly higher in persons with the excess of weight, increase of fat thickness, hypercholesterolemia as well as in the group with coronary disease and cerebrovascular pathology as compared to the mean values in whole population.
Asunto(s)
Presión Sanguínea , Hipertensión/epidemiología , Población Urbana/estadística & datos numéricos , Adulto , Factores de Edad , Causas de Muerte , Trastornos Cerebrovasculares/epidemiología , Trastornos Cerebrovasculares/mortalidad , Trastornos Cerebrovasculares/patología , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/mortalidad , Enfermedad Coronaria/patología , Humanos , Hipertensión/mortalidad , Hipertensión/patología , Letonia/epidemiología , Masculino , Persona de Mediana Edad , Factores de RiesgoRESUMEN
The epidemiological autopsy study of 1338 men in Riga aged 20-59 was repeated 20-25 years after the first similar investigation. Aortas were stained with Sudan IV and atherosclerotic lesions were graded by visual-planimetric method. It was the significant growth, with age, of all kinds of lesions except lipoid streaks, having the most prominent increase in men aged 40-49. In the abdominal aorta the extent of lesions was significantly higher than in the thoracic aorta beginning from the fourth decade of life. Significant increase of various lesions in aorta was observed in the same male population 20-25 years after the first examination. The tendency to the earlier transition of fibrous plaques into more severe forms of atherosclerosis (complicated lesions and calcinosis) is noted.
Asunto(s)
Enfermedades de la Aorta/epidemiología , Arteriosclerosis/epidemiología , Adulto , Factores de Edad , Aorta Abdominal/patología , Aorta Torácica/patología , Enfermedades de la Aorta/patología , Arteriosclerosis/patología , Humanos , Letonia/epidemiología , Masculino , Persona de Mediana EdadRESUMEN
Ultrasound densitometry was used to determine echo density of the wall and contents of the gallbladder in normal persons and in patients suffering from cholelithiasis and chronic calculus-free cholecystitis. In patients with cholelithiasis, the gallbladder was later removed, followed by histological examination of its wall. The ultrasound and histological data were studied and compared. The highly significant differences in the echo density of the wall and contents of the gallbladder were obtained in normal persons and patients afflicted with chronic cholecystitis.
Asunto(s)
Colecistitis/diagnóstico , Vesícula Biliar/patología , Ultrasonografía/métodos , Adulto , Colelitiasis/diagnóstico , Enfermedad Crónica , Densitometría/métodos , Humanos , Valores de ReferenciaRESUMEN
The increased body mass (Quetelet index greater than or equal to 30.0) in 1447 autopsies of Riga's male population aged 20-59 years was revealed in 8.6% of all cases. A significant rise of mean values of the Quetelet index was found in the presence of arterial hypertension, hypercholesterolemia, increased thickness of subcutaneous fat and diabetes mellitus. The mean value of the Quetelet index was significantly higher in cases of coronary and cerebrovascular death victims than that seen in the 20-59-year old group and apparently healthy persons.
Asunto(s)
Índice de Masa Corporal , Población Urbana , Adulto , Factores de Edad , Autopsia/estadística & datos numéricos , Peso Corporal , Trastornos Cerebrovasculares/epidemiología , Trastornos Cerebrovasculares/mortalidad , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/mortalidad , Humanos , Letonia/epidemiología , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Obesidad/mortalidad , Factores de RiesgoRESUMEN
Neoplasms and cardiovascular diseases were the most common causes of death in an investigation of 518 autopsies of Riga females aged 20 to 59 years. The prevalence of examined risk factors in this population was as follows: Arterial hypertension: 15.2%; hypercholesterolemia: 28.1%; smoking: 42.1%; overweight: 22.4%; increased thickness of subcutaneous fat tissue: 54.0%; low physical activity: 65.4%; diabetes mellitus: 4.9%. Coronary and vascular deaths were highest in incidence among persons with arterial hypertension, overweight, and increased fat tissue thickness.
Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Causas de Muerte , Neoplasias/mortalidad , Adulto , Enfermedades Cardiovasculares/etiología , Complicaciones de la Diabetes , Diabetes Mellitus/epidemiología , Femenino , Humanos , Hipercolesterolemia/complicaciones , Hipercolesterolemia/epidemiología , Hipertensión/complicaciones , Hipertensión/epidemiología , Letonia , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Fumar/efectos adversos , Fumar/epidemiologíaRESUMEN
Thromboembolism was found in 1060 (11.9%) of 8926 retrospectively studied autopsies. Thromboembolism of the lesser (pulmonary) circulation was the most frequent (7.3%), the domination of females was noted (62.8%). Peak in both males and females was within the age group of 70 to 79 years. The most frequent source of the pulmonary circulation thromboembolism was the lower limb veins. Thromboembolism of the pulmonary (31.9%) and greater (61%) circulation was most frequently observed in the ischemic heart disease. Monthly variations were not statistically significant.
Asunto(s)
Tromboembolia/epidemiología , Adulto , Factores de Edad , Anciano , Femenino , Humanos , Letonia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Embolia Pulmonar/complicaciones , Embolia Pulmonar/epidemiología , Riesgo , Estaciones del Año , Factores Sexuales , Tromboembolia/complicaciones , Vena Cava InferiorRESUMEN
Combined thromboembolism of both the greater and the lesser circulation was found in 164 cases (1.8%) among 8926 autopsies; in 9 observations (0.1%) paradoxical thromboembolism was detected. The factors responsible for this complication were as follows: advanced age, the increase of weight and thickness of the right ventricle, the increase of the ventricular index, the presence of chronic respiratory diseases with the development of pulmonary-cardiac decompensation.