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2.
J Med Microbiol ; 70(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33533709

RESUMO

Introduction. Streptococcus dysgalactiae subsp. equisimilis (SDSE) is a ß-hemolytic streptococcus that causes severe invasive streptococcal infections, especially in the elderly and people with underlying diseases. SDSE strains are primarily characterized by Lancefield group G or C antigens.Hypothesis/Gap Statement. We have previously reported the prevalence of Lancefield group A SDSE (GA-SDSE) strains in Japan and have analysed the draft genome sequences of these strains. As GA-SDSE is a rare type of SDSE, only one complete genome has been sequenced to date.Aim. The present study is focused on genetic characteristics of GA-SDSE strains. In order to examine molecular characteristics, we also tested growth inhibition of other streptococci by GA-SDSE.Methodology. We determined the complete genome sequences of three GA-SDSE strains by two new generation sequencing systems (short-read and long-read sequencing data). Using the sequences, we also conducted a comparative analysis of GA-SDSE and group C/G SDSE strains. In addition, we tested multiplex and quantitative PCRs targeting the GA-SDSE, group G SDSE, and S. pyogenes.Results. We found a group-specific conserved region in GA-SDSE strains that is composed of genes encoding predicted anti-bacteriocin and streptococcal lantibiotic (Sal) proteins. Multiplex and quantitative PCRs targeting the GA-SDSE-specific region were able to distinguish between GA-SDSE, other SDSE, and S. pyogenes strains. The growth of GA-SDSE was suppressed in the presence of group G SDSE, indicating a possible explanation for the low frequency of isolation of GA-SDSE.Conclusion. The comparative genome analysis shows that the genome of GA-SDSE has a distinct arrangement, enabling the differentiation between S. pyogenes, GA-SDSE, and other SDSE strains using our PCR methods.


Assuntos
Genoma Bacteriano/genética , Streptococcus/genética , Streptococcus/isolamento & purificação , Proteínas de Bactérias/genética , Técnicas de Cocultura , Variação Genética , Ilhas Genômicas , Humanos , Japão , Especificidade da Espécie , Infecções Estreptocócicas/microbiologia , Streptococcus/crescimento & desenvolvimento , Streptococcus pyogenes/genética , Streptococcus pyogenes/crescimento & desenvolvimento , Streptococcus pyogenes/isolamento & purificação
3.
Front Microbiol ; 11: 552418, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33072013

RESUMO

Streptococcus dysgalactiae subsp. equisimilis (SDSE) causes cellulitis, bacteremia, and invasive diseases, such as streptococcal toxic shock syndrome. Although SDSE infection is more prevalent among elderly individuals and those with diabetes mellitus than infections with Streptococcus pyogenes (Group A streptococci; GAS) and Streptococcus agalactiae (Group B streptococci; GBS), the mechanisms underlying the pathogenicity of SDSE remain unknown. SDSE possesses a gene hylD encoding a hyaluronate lyase (HylD), whose homologue (HylB) is involved in pathogenicity of GBS, while the role of HylD has not been characterized. In this study, we focused on the enzyme HylD produced by SDSE; HylD cleaves hyaluronate (HA) and generates unsaturated disaccharides via a ß-elimination reaction. Hyaluronate-agar plate assays revealed that SDSE promoted dramatic HA degradation. SDSE expresses both HylD and an unsaturated glucuronyl hydrolase (UGL) that catalyzes the degradation of HA-derived oligosaccharides; as such, SDSE was more effective at HA degradation than other ß-hemolytic streptococci, including GAS and GBS. Although HylD shows some homology to HylB, a similar enzyme produced by GBS, HylD exhibited significantly higher enzymatic activity than HylB at pH 6.0, conditions that are detected in the skin of both elderly individuals and those with diabetes mellitus. We also detected upregulation of transcripts from hylD and ugl genes from SDSE wild-type collected from the mouse peritoneal cavity; upregulated expression of ugl was not observed in ΔhylD SDSE mutants. These results suggested that disaccharides produced by the actions of HylD are capable of triggering downstream pathways that catalyze their destruction. Furthermore, we determined that infection with SDSEΔhylD was significantly less lethal than infection with the parent strain. When mouse skin wounds were infected for 2 days, intensive infiltration of neutrophils was observed around the wound areas infected with SDSE wild-type but not SDSEΔhylD. Our investigation suggested that HylD and UGL play important roles in nutrient acquisition from hosts, followed by the bacterial pathogenicity damaging host tissues.

4.
Mod Pathol ; 19(2): 291-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16424896

RESUMO

Infantile hemangiomas are common benign vascular tumors that exhibit a characteristic history of rapid proliferation in the first year of life and slow spontaneous involution during early childhood. The causative pathogenic event responsible for the abnormal endothelial proliferation remains elusive. The recent discovery of an immature phenotype of proliferating hemangioma endothelial cells due to the exclusive expression of the lymphatic endothelial hyaluronan receptor LYVE-1 led to the proposal that infantile hemangiomas are the result of a primary defect in endothelial cell maturation. To test this hypothesis, we looked for the expression of the lymphatic endothelial cell-specific markers LYVE-1, Prox-1, podoplanin and D2-40 in beta4 integrin-negative proliferating and beta4 integrin-positive involuting infantile hemangiomas. As beta4 integrin proved to be a suitable marker for staging infantile hemangiomas, we used it in combination with clinical and histological criteria to objectively determine the proliferative and involutional phases. In immunohistochemical and immunofluorescent stains, hemangioma vessels were negative for all lymphatic endothelial cell-specific markers tested during both proliferation and involution. LYVE-1 immunoreactivity, however, was found in the dense network of perivascular HLA-DR-positive cells with dendritic cell morphology that are supposed to play a role in hemangiogenesis by releasing pro- and antiangiogenic factors. Notably, this LYVE-1 staining failed to correlate with the growth status of infantile hemangiomas. Our results do not support the notion that LYVE-1 expression was restricted to the proliferative phase and downregulated during involution. Thus, LYVE-1 does not seem to be a reliable marker for proliferating infantile hemangiomas. We conclude that the suggested intrinsic defect in endothelial cell maturation is unlikely the cause for the post-natal rapid growth in infantile hemangiomas. In addition, the lack of lymphatic endothelial cell-specific markers implies that infantile hemangiomas are tumors of blood vessels without lymphatic competence.


Assuntos
Células Endoteliais/patologia , Glicoproteínas/análise , Hemangioma/patologia , Antígenos CD34/análise , Proliferação de Células , Células Endoteliais/química , Feminino , Imunofluorescência , Antígenos HLA-DR/análise , Hemangioma/metabolismo , Humanos , Imuno-Histoquímica , Lactente , Masculino , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Proteínas de Transporte Vesicular , Fator de von Willebrand/análise
5.
Artigo em Vietnamês | WPRIM (Pacífico Ocidental) | ID: wpr-4137

RESUMO

Varicocele is a dilatation of plexus venosus in the spermatic cord. It rarely occurs before the age of puberty, but 15% of male teenager experienced varicocele (the rate is relatively high). This rate is higher when surveying data of male infertility (35% of primary infertility patients, and 75-81% of secondary infertility patients had experienced varicocele). Varicocele may affect both sides, but 90% of cases occurred in 1 side and among them 90% were in the left side. Microsurgery is a treatment with high rate of success


Assuntos
Varicocele , Cordão Espermático , Microcirurgia , Diagnóstico , Terapêutica , Conhecimento
6.
Artigo em Vietnamês | WPRIM (Pacífico Ocidental) | ID: wpr-4118

RESUMO

To survey the basic measurements of urodynamic as cystometry, uroflowmetry, electromyography, urethral profilometry. Currently, it may be to combine measurements each other or urodynamic with image diagnostic technique in order to have comprehensive consideration, more accurate on lower urinary tract function: To combine with cystometry, uroflowmetry and electromyography, detrusor pressure measurement, to combine with cystometry and observe reflection of light of cystoids under fluorescent screen, video-urodynamics


Assuntos
Urodinâmica , Eletromiografia , Sistema Urinário
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