RESUMEN
Fluorescence in situ hybridization (FISH) was for the first time used to study the chromosomal location of the 45S (18-2.5S-26S) and 5S ribosomal genes in the genomes of five flax species of the section Linum (syn. Protolinum and Adenolinum). In L. usitatissimum L. (2n = 30), L. angustifolium Huds. (2n = 30), and L. bienne Mill. (2n = 30), a major hybridization site of 45S rDNA was observed in the pericentric region of a large metacentric chromosome. A polymorphic minor locus of 45S rDNA was found on one of the small chromosomes. Sites of 5S rDNA colocalized with those of 45S rDNA, but direct correlation between signal intensities from the 45S and 5S rDNA sites was observed only in some cases. Other 5S rDNA sites mapped to two chromosomes in these flax species. In L. grandiflorum Desf. (2n = 16) and L. austriacum L. (2n = 18), large regions of 45S and 5S rDNA were similarly located on a pair of homologous satellite-bearing chromosomes. An additional large polymorphic site of 45S and 5S rDNA was found in the proximal region of one arm of a small chromosome in the L. usitatissimum. L. angustifolium, and L. bienne karyotypes. The other arm of this chromosome contained a large 5S rDNA cluster. A similar location of the ribosomal genes in the pericentric region of the pair of satellite-bearing metacentrics confirmed the close relationships of the species examined. The difference in chromosomal location of the ribosomal genes between flax species with 2n = 30 and those with 2n = 16 or 18 testified to their assignment to different sections. The use of ribosomal genes as chromosome markers was assumed to be of importance for comparative genomic studies in cultivated flax, a valuable crop species of Russia, and in its wild relatives.
Asunto(s)
Mapeo Cromosómico , ADN Ribosómico/genética , Lino/genética , Hibridación Fluorescente in Situ , Cariotipificación , Especificidad de la EspecieRESUMEN
Chromosome C-banding patterns were analyzed in three closely related flax species (Linum usitatissimum L., 2n = 30; L. angustifolium Huds., 2n = 30; and L. bienne Mill., 2n = 30) and their hybrids. In each case, the karyotype included metacentrics, submetacentrics, and one or two satellite chromosomes. Chromosomes of the three flax species were similar in morphology, size (1-3 microns), and C-banding pattern and slightly differed in size of heterochromatic regions. In all accessions, a large major site of ribosomal genes was revealed by hybridization in the pericentric region of a large metacentric. A minor 45S rDNA site was observed on a small chromosome in L. usitatissimum and L. bienne and on a medium-sized chromosome in L. angustifolium. Upon silver staining, a nucleolus-organizing region (NOR) was detected on a large chromosome in all species. In L. angustifolium, an Ag-NOR band was sometimes seen on a medium-sized chromosome. In the karyotypes of interspecific hybrids, silver-stained rDNA loci were observed on satellite chromosomes of both parental species. RAPD analysis with 22 primers revealed a high similarity of the three species. The greatest difference was observed between L. angustifolium and the other two species. The RAPD patterns of L. bienne and L. usitatissimum differed in fewer fragments. A dendrogram of genetic similarity was constructed for the three flax species on the basis of their RAPD patterns. Genome analysis with chromosome and molecular markers showed that L. bienne must be considered as a subspecies of L. usitatissimum rather than a separate species. The three species were assumed to originate from a common ancestor, L. angustifolium being closest to it.
Asunto(s)
Quimera , Lino/genética , Genoma de Planta , Bandeo Cromosómico , Cruzamientos Genéticos , ADN Ribosómico/genética , Lino/clasificación , Marcadores Genéticos , Heterocromatina/genética , Cariotipificación , Región Organizadora del Nucléolo/metabolismo , Técnica del ADN Polimorfo Amplificado Aleatorio , Tinción con Nitrato de Plata , Especificidad de la EspecieRESUMEN
Analysis of the remission incidence and duration has been made in 71 patients with severe progressive rheumatoid arthritis (RA) during the 10-20-year follow-up period, with special attention paid to the role of the disease-modifying drugs (DMARDs). Remission occurred only in those patients who received permanent long-term systematic treatment with DMARDs. Such a therapeutic approach resulted in remission lasting from 5 to 11 years for 32% of the patients. Otherwise the patients who received episodic non-regular DMARDs therapy or symptomatic treatment with nonsteroidal anti-inflammatory drugs or steroids had no remission at all. A detailed analysis of the cases of remission is presented. The authors are of the opinion that after the disappearance of the clinical signs of RA the maintenance basic therapy may be continued.
Asunto(s)
Antiinflamatorios/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Adulto , Artritis Reumatoide/epidemiología , Artritis Reumatoide/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Inducción de Remisión , Factores de TiempoRESUMEN
Analysis was made of the results of basic therapy carried out for 10-15 years in 71 patients suffering from rheumatoid arthritis (RA) bearing in mind the systematic nature of the treatment. The study included patients with the progressive disease variety and the onset of observation instituted within the first 5 years of RA. It is shown that only basic therapy carried out for many years and practically continuously during the observation period made it possible to control the disease. As a result of such treatment policy, 50% of the patients manifested for a long time (6-10 years) a pronounced decrease or complete suppression of RA activity followed by remission, which was accompanied by retardation and the ceasing of the progression of x-ray alterations and functional insufficiency of the joints. Nonsystematic basic treatment did not exert any material effect on RA. The results of such therapy in patients with the RA standing 10-20 years did not differ from those without the use of the basic drugs.
Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/uso terapéutico , Artritis Reumatoide/epidemiología , Artritis Reumatoide/mortalidad , Artritis Reumatoide/fisiopatología , Quimioterapia Combinada , Estudios de Seguimiento , Glucocorticoides/efectos adversos , Glucocorticoides/uso terapéutico , Humanos , Articulaciones/fisiopatología , Estudios Prospectivos , Inducción de Remisión , Factores de TiempoRESUMEN
The paper is concerned with the data obtained during 17-year prospective follow-up of over 500 patients with rheumatoid arthritis (RA) who received individualized treatment mainly with basic drugs. Cases of repair of bone erosions in small joints of the hands and feet are described as are cases of complete or partial repair of osteolysis in 8 patients with significant RA treated for a long time with parenteral or oral gold drugs, or D-penicillamine in different daily doses.