RESUMO
Here, we report the characterization of 22 clinical toxigenic V. cholerae non-O1/non-O139 strains isolated in the Middle Asia (Uzbekistan) in 1971-1990. PCR analysis has revealed that these strains contain the main virulence genes such as ctxA, zot, ace (CTXφ); rstC (RS1φ); tcpA, toxT, aldA (pathogenicity island VPI), but they lack both pandemic islands VSP-I and VSP-II specific to epidemic strains of O1 serogroup of El Tor biotype and O139 serogroup. Only two of the twenty two toxigenic strains have tcpA gene of El Tor type, one strain has tcpA gene of classical type, while nineteen other strains carry a new variant of this gene, designated as tcpA(uzb).. Nucleotide sequences analysis of virulence genes in toxigenic V. cholerae non-O1/non-O139 strains from Uzbekistan showed that they differ significantly from the sequences of these genes in epidemic O1 and O139 strain indicating that they belong to a separate line of evolution of virulent V. cholerae strains. For the first time it is shown that V. cholerae non-O1/non-O139 toxigenic strains of different serogroups may belong to the same clone.
Assuntos
Vibrio cholerae O139/genética , Vibrio cholerae O139/patogenicidade , Vibrio cholerae não O1/genética , Vibrio cholerae não O1/patogenicidade , Proteínas de Bactérias/genética , Sequência de Bases , Proteínas de Fímbrias/genética , Dados de Sequência Molecular , Antígenos O/genética , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Uzbequistão , Vibrio cholerae O139/isolamento & purificação , Vibrio cholerae não O1/isolamento & purificação , Virulência/genéticaRESUMO
Prevalence of vcs genes coding the type III secretion system (T3SS) in cholera vibrios of different serogroups isolated in Russia and neighboring countries was studied for the first time. Virulent strains of O1 and O139 serogroups as well as toxigenic Vibrio cholerae strains of other serogroups contained no T3SS genes. Unlike mentioned strains, 29.2% of atoxigenic non O1/non O139 cholera vibrios isolated from patients in Russia and neighboring countries contained the T3SS genes cluster, which might contribute to the pathogenic properties of these strains.
Assuntos
Cólera/microbiologia , Genes Bacterianos , Família Multigênica , Via Secretória/genética , Vibrio cholerae/genética , Vibrio cholerae/metabolismo , Sudeste Asiático/epidemiologia , Proteínas de Bactérias/metabolismo , Cólera/epidemiologia , Microbiologia Ambiental , Humanos , Federação Russa/epidemiologia , Sorotipagem , Turcomenistão/epidemiologia , Uzbequistão/epidemiologia , Vibrio cholerae/classificação , Vibrio cholerae/patogenicidade , Virulência/genéticaRESUMO
A total of 199 sessions of photodynamic therapy (PDT) with visudine were performed in 119 patients (227 eyes) at the Laser Center, T. I. Yeroshevsky Samara eye diseases hospital. Analysis of the changes occurring in visual function in the presence of the subretinal neovascular membrane developing in age-related macular dystrophy and high complicated myopia showed an increase in visual functions in the first 3-6 months after PDT, which is, in the authors' opinion, associated with the diminution of macular edema and the resolution of hemorrhage. In the subsequent months, visual acuity tended to slightly lower. The late follow-up periods (after 1.5 years) saw visual function stabilization. Visudine PDT for subretinal neovascularization is an effective, safe, technically simple, well-tolerable procedure that makes it possible not only to stabilize, but, in many cases, to improve visual functions. A follow-up of patients for as long as 18 months demonstrated that stable visual functions were retained with a slight tendency for their reduction during continued PDT sessions.
