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1.
Vestn Oftalmol ; 139(5): 5-13, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37942591

RESUMO

PURPOSE: The study aims to determine the indications and evaluate the results of primary vitrectomy in unfavorable progression of stage III active retinopathy of prematurity (ROP). MATERIAL AND METHODS: The control group consisted of 17 patients (28 eyes) with unfavorable progression of stage III ROP, who had the disease progress after coagulation of the avascular retina and underwent the second stage of treatment - vitrectomy. The main group consisted of 5 patients (10 eyes) with unfavorable progression of stage III ROP, who underwent primary vitrectomy. Gestational age at birth was 24-30 weeks, body weight ranged from 680 to 1250 g. According to spectral optical coherence tomography (SOCT) and OCT angiography (OCT-A), the initial state of the retina and vitreoretinal interface in patients of the main and control groups were identical. RESULTS: A retrospective analysis of control patients, according to SOCT and OCT-A data, showed the spread of neovascularization beyond the retinal plane, its interaction with the posterior hyaloid membrane and vitreous body structures in the early stages of the disease, traction changes in the underlying retina, areas of retinoschisis, as well as thickening of the posterior hyaloid membrane. The tactics of treating patients with unfavorable progression of stage III ROP has changed since 2020. Primary vitrectomy was performed in case the signs listed above were identified. The transition of the disease to the inactive stage was recorded in all cases one month after primary vitrectomy. After one year the pathological process did not reactivate in any of the cases, and no pathological changes were found in the projection of the former proliferation ridge. CONCLUSIONS: Extraretinal retinovitreal neovascularization, according to multimodal preoperative diagnostics, indicates the need for vitreoretinal surgery as a pathogenetically substantiated method of treatment for unfavorable progression of stage III active ROP.


Assuntos
Retinopatia da Prematuridade , Recém-Nascido , Humanos , Lactente , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/cirurgia , Vitrectomia , Estudos Retrospectivos , Fotocoagulação a Laser/métodos , Retina/diagnóstico por imagem , Retina/cirurgia , Retina/patologia , Idade Gestacional
2.
Vestn Oftalmol ; 130(4): 49-56, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25306724

RESUMO

Dynamic evaluation of the diameters of central fundus vessels, 2nd order and peripheral vessels as well as the tortuosity index of central zone arteries in stage II and III retinopathy of prematurity (ROP), which showed regression after laser treatment, was performed. Obtained data can be used for estimation of the optimal follow-up period ensuring early detection of high probability for ROP progression after laser coagulation and decrease of the number of diagnostic examinations for patients whose pathologic process is resolving.


Assuntos
Fotocoagulação , Artéria Retiniana , Retinopatia da Prematuridade , Técnicas de Diagnóstico Oftalmológico , Progressão da Doença , Diagnóstico Precoce , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Recém-Nascido , Fotocoagulação/métodos , Fotocoagulação/estatística & dados numéricos , Masculino , Prognóstico , Artéria Retiniana/patologia , Artéria Retiniana/fisiopatologia , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/fisiopatologia , Retinopatia da Prematuridade/terapia , Índice de Gravidade de Doença , Resultado do Tratamento
3.
Vestn Oftalmol ; 130(3): 26-31, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25098118

RESUMO

PURPOSE: To define diagnostic morphometric parameters of central fundus and peripheral retinal vessels that characterize different types of retinopathy of prematurity (ROP) course. MATERIAL AND METHODS: A total of 155 premature infants (310 eyes) with stage I, II, and III ROP were assessed as they were undergoing treatment in the Kaluga branch of "Eye Microsurgery" complex during 2010-2012. Patients with the same stage of the disease were divided into two groups according to the type of ROP course (type 1--ROP with low risk of progression, type 2--ROP with high risk of progression). Original ROP-MORPHOMETRY software was used for morphometric analysis of digital images of the fundus taken with RetCam 120 and RetCam 3 through a 130 degree lens. RESULTS: Regardless the stage of the disease, larger diameter of retinal vessels and higher tortuosity index was found in type 2 ROP (favorable) as compared with type 1 ROP (unfavorable). An observation was made, that the father from the central fundus the narrower became the vessels of both nasal and temporal arcades. CONCLUSION: The obtained quantitative morphometric data can help to clearly determine the risk of progression at any stage of ROP.


Assuntos
Retina , Vasos Retinianos , Retinopatia da Prematuridade , Pesquisa Comparativa da Efetividade , Técnicas de Diagnóstico Oftalmológico , Progressão da Doença , Feminino , Fundo de Olho , Idade Gestacional , Humanos , Processamento de Imagem Assistida por Computador/métodos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Gravidade do Paciente , Prognóstico , Retina/patologia , Retina/fisiopatologia , Vasos Retinianos/patologia , Vasos Retinianos/fisiopatologia , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/fisiopatologia
5.
Phys Rev Lett ; 93(16): 161103, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15524972

RESUMO

The151Sm(n,gamma)152Sm cross section has been measured at the spallation neutron facility n_TOF at CERN in the energy range from 1 eV to 1 MeV. The new facility combines excellent resolution in neutron time-of-flight, low repetition rates, and an unsurpassed instantaneous luminosity, resulting in rather favorable signal/background ratios. The 151Sm cross section is of importance for characterizing neutron capture nucleosynthesis in asymptotic giant branch stars. At a thermal energy of kT=30 keV the Maxwellian averaged cross section of this unstable isotope (t(1/2)=93 yr) was determined to be 3100+/-160 mb, significantly larger than theoretical predictions.

6.
Izv Akad Nauk Ser Biol ; (1): 94-9, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10881433

RESUMO

Our studies have been conducted in Southern Kalmykia (Black Lands) in 1994-1996. The data obtained on the same territories in 1981-1983, as well as in 1997-1998 were used for comparison. Over the studied period, the size of Meriones tamariscinus population underwent a significant increase. In the early 1980s, the colonies of this species were found only on sandy dunes covered with tamarix. At the present time, M. tamariscinus populations have spread over stabilized sands, abandoned shepherd camps, and riparian thickets of tamarix along the shores of lakes. Both gerbils species (M. meridianus and M. tamariscinus) establish joint colonies in all biotopes, but not in riparian tamarix thickets near lakes, where only Meriones tamariscinus have been found. The abundance of food and favorable conditions for burrowing in stable sands belong to factors, responsible for permanently high numbers of gerbils in these areas.


Assuntos
Gerbillinae , Animais , Demografia , Federação Russa , Estações do Ano , Especificidade da Espécie
7.
Izv Akad Nauk Ser Biol ; (3): 332-44, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10868058

RESUMO

Today, pastural ecosystems of the Kalmyk Republic demonstrate progressive regrowth dynamics, which is explained by a sharp decrease in grazing load and the onset of a new humidification cycle in the Caspian Lowland. By the mid-1990s, the sparse and poor desert vegetation with a significant proportion of ephemerals, characteristic of these ecosystems in the 1980s, had been substituted by highly productive tall-grass communities typical of steppes. Under such conditions, corresponding changes in the distribution and abundance of rodents could be expected. These parameters were assessed in different types of habitats in Chernye Zemli (the Kalmyk Black Lands) from 1980 to 1983 and from 1993 to 1997. Rodents were captured in live traps distributed over permanent test plots and in crush traps arranged in lines. The results showed that the population of midday gerbils did not change significantly during this period, although their favorite open habitats considerably decreased in area. The abundance and range of tamarisk gerbils noticeably increased, whereas those of little sousliks continued to decrease, contrary to our expectations. Thus, a rapid progressive succession in plant communities did not cause the corresponding change (of similar rate and extent) in the structure of rodent community. The difference between the observed and expected results provides evidence that rodent populations are somewhat "inert" in their response to changes in environmental conditions, and their development is relatively independent of these changes, but is contingent upon the state of populations in the past (i.e., the history of colonies).


Assuntos
Clima , Ecossistema , Roedores , Animais , Umidade , Densidade Demográfica , Dinâmica Populacional , Federação Russa
8.
Genetika ; 35(7): 961-8, 1999 Jul.
Artigo em Russo | MEDLINE | ID: mdl-10519073

RESUMO

The allozyme variation in three spiny rat species of the genus Proechimys from Upper Amazonia was studied in relation to their ecology and evolution. The ecological environmental factors and biotopic distribution of species were analyzed. The unusually high allozyme variation was found in P. simonsi and P. sp. (2n = 34) inhabiting native forest biotopes. A relatively low allozyme variation in P. brevicauda was assumed to be associated with eurybiotic properties and the ability of this species to adapt to anthropogenic biotopes. Data on chromosome homeology and reconstruction of chromosome rearrangements in six spiny rat species were correlated with allozyme variation. The results suggested that chromosome rearrangements played the major role in evolution of the spiny rat species, and that the reorganization of the P. brevicauda genome was not random. P. simonsi and P. sp. (2n = 34), which live in native forest biotopes and carry an excessive genomik "informational load", were assumed to be highly susceptible to any novel external factors. These species are potentially able to produce new chromosome forms and are most significantly affected by deforestation.


Assuntos
Evolução Molecular , Variação Genética , Isoenzimas/genética , Roedores/genética , Animais , Ecossistema , Especificidade da Espécie
10.
Genetika ; 32(1): 83-92, 1996 Jan.
Artigo em Russo | MEDLINE | ID: mdl-8647427

RESUMO

A karyological analysis of three species of South American field mice of the genus Akodon from four different localities of the Department of Tarija, Bolivian Republic, was performed. In Akodon simulator, 2n = 40 - 42, NFa = 42. The variation of the diploid number is caused by a polymorphism of the Robertsonian type involving six pairs of acrocentric chromosomes. Five variants of karyotypes were revealed. The chromosome set of A. sp. has 2n = 36, NFa = 40; in A. toba, 2n = 42 - 43, NFa = 44 - 46. The variation of the diploid number and the number of autosomal arms is caused by the polymorphism of the first autosomal pair. A comparative karyological analysis of A. simulator, A. sp., and A. toba revealed a high level of similarity of all karyotypic elements. Fifteen autosomal pairs of these three species have identical G-banding patterns; the others are involved in formation of larger chromosomes, representing one possible combination of the same chromosomal material. The set of rearrangements is limited only to tandem chromosome fusions.


Assuntos
Arvicolinae/genética , Mapeamento Cromossômico , Animais , Bolívia , Bandeamento Cromossômico , Rearranjo Gênico , Cariotipagem , Polimorfismo Genético , Especificidade da Espécie
11.
Eksp Klin Farmakol ; 56(5): 53-5, 1993.
Artigo em Russo | MEDLINE | ID: mdl-8312815

RESUMO

The effects of glycosamine aminosugar on the processes of endotoxicosis and lipid peroxidation were thoroughly studied in rats with toxic pulmonary edema. There was a glycosamine-induced decrease in markers of endotoxicosis, such as medium-weight molecular peptides and malonic dialdehyde in serum and lung tissue. Administration of exogenous glucosamine resulted in its incorporation into the membranes of target organs, connective tissue and normalized the levels of endogenous N-acetyl-glucosamine, which finally determined antitoxic and antioxidative properties in this aminosugar.


Assuntos
Glucosamina/uso terapêutico , Edema Pulmonar/tratamento farmacológico , Cloreto de Amônio , Animais , Avaliação Pré-Clínica de Medicamentos , Glucosamina/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Substâncias Macromoleculares , Malondialdeído/metabolismo , Peso Molecular , Peptídeos/efeitos dos fármacos , Peptídeos/metabolismo , Edema Pulmonar/induzido quimicamente , Edema Pulmonar/metabolismo , Ratos
12.
Genetika ; 27(8): 1431-9, 1991 Aug.
Artigo em Russo | MEDLINE | ID: mdl-1761215

RESUMO

Karyological analysis of spiny rats of the genus Proechimys revealed four chromosome forms: 2n = 30; 2n = 29; 2n = 28; 2n = 24. 30-chromosome spiny rats are characterized by unique karyotype constitution. 27-chromosome spiny rats from the territory near Iquitos differ from the same of Pucalpa (Ucayali Department) by Y-chromosome structure and banding of long arms with two pairs of autosomes. 24-chromosome rats from the regions mentioned above do not differ in G-banded chromosomes. Diploid chromosome set equal to 29, has a family originated from the parents which had 2n = 30 and 2n = 28 under the laboratory conditions. The absence of clear morphological differentiation, similarity of constituent parts of the karyotype and hybridization possibility point to relatively recent origination of the chromosome forms under study.


Assuntos
Bandeamento Cromossômico , Cromossomos , Roedores/genética , Animais , Diploide , Hibridização Genética/genética , Cariotipagem , Cromossomo Y
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