StreptoBase: An oral Streptococcus mitis group genomic resource and analysis platform

The oral streptococci are spherical Gram-positive bacteria categorized under the phylum Firmicutes which are among the most common causative agents of bacterial infective endocarditis (IE) and are also important agents in septicaemia in neutropenic patients. The Streptococcus mitis group is comprised of 13 species including some of the most common human oral colonizers such as S. mitis, S. oralis, S. sanguinis and S. gordonii as well as species such as S. tigurinus, S. oligofermentans and S. australis that have only recently been classified and are poorly understood at present. We present StreptoBase, which provides a specialized free resource focusing on the genomic analyses of oral species from the mitis group. It currently hosts 104 S. mitis group genomes including 27 novel mitis group strains that we sequenced using the high throughput Illumina HiSeq technology platform, and provides a comprehensive set of genome sequences for analyses, particularly comparative analyses and visualization of both cross-species and cross-strain characteristics of S. mitis group bacteria. StreptoBase incorporates sophisticated in-house designed bioinformatics web tools such as Pairwise Genome Comparison (PGC) tool and Pathogenomic Profiling Tool (PathoProT), which facilitate comparative pathogenomics analysis of Streptococcus strains. Examples are provided to demonstrate how StreptoBase can be employed to compare genome structure of different S. mitis group bacteria and putative virulence genes profile across multiple streptococcal strains. In conclusion, StreptoBase offers access to a range of streptococci genomic resources as well as analysis tools and will be an invaluable platform to accelerate research in streptococci

Methodological variations in the isolation of genomic DNA from Streptococcus bacteria

In this work, genomic DNA of Streptococcus pyogenes, S. mutans and S. sobrinus was isolated using two methods: either using the detergent cetyltrimethylammonium bromide (CTAB) at 65ºC; or by applying ultrasound to a mixture of silica and celite in CTAB. The composite method that used ultrasound was the more efficient, allowing the straightforward extraction of genomic DNA from Gram-positive bacteria with good quality and reproducibility.<br>O gênero Streptococcus encontra-se amplamente distribuído na natureza e algumas espécies constituem a microbiota humana da cavidade bucal, como Streptococcus pyogenes, que pode estar associado a importantes doenças humanas, Streptococcus mutans e Streptococcus sobrinus, relacionados à cárie dental. O DNA genômico destas três espécies foi isolado utilizando-se dois métodos, o primeiro utilizando o detergente brometo de cetiltrimetilamônio (CTAB) à 65ºC e outro associando ultra-som a uma mistura de sílica e celite em CTAB. O método que possibilitou a extração do DNA genômico das bactérias Gram positivas, com qualidade, boa reprodutibilidade fácil execução foi aquele que utilizou ultra-som associado à sílica e celite em CTAB

In transit metastases of malignant melanoma treated by high dose rTNFα in combination with interferon-γ and melphalan in isolation perfusion

To increase the therapeutic efficacy of recombinant tumor necrosis factor alpha (rTNFα) and reduce the systemic side effects, a protocol was designed using isolation perfusion of the limbs with hyperthermia for in transit metastases of melanoma. A triple combination of high dose rTNFα + recombinant interferon-gamma (rIFN-γ) + melphalan was chosen because of a synergistic anti-tumor effect of rTNFα with rIFN-γ and of rTNFα with alkylating agents reported in the literature. Twenty-nine patients of mean age 60 years (range 22-82 years) entered the study after informed consent and received a total of 31 isolation perfusions with the triple combination. There were 24 women and 5 men with multiple progressive in transit melanoma metastases of the lower limb (stage IIIa or IIIab). rTNFα at the unique dose of 4 mg was injected as a bolus in the arterial line, under mild hyperthermic conditions (40 to 40.5°C) for 90 minutes. rIFN-γ was given subcutaneously on days -2 and -1 and in the perfusate, with rTNFα, at the dose of 0.2 mg. Melphalan was administered in the perfusate at dose giving a concentration of 40 μg/ml. In all the 31 isolation perfusions performed in the triple combination protocol, in order to prevent a septic shock-like syndrome which had been encountered in 2 patients treated outside this protocol for sarcoma and carcinoma, the patients received dopamine continuous infusion at 3 μg/kg/min from the start of isolation perfusion and for 48 hours, and only showed mild hyptension and very transient chills and temperature. Regional toxicity attributable to rTNFα was minimal. There have been 16 patients with hematologic toxicity consisting of neutropenia (11 cases, 1 case grade 4 and 1 case grade 3) and neutropenia with thrombocytopenia (12 cases, 1 case grade 4 and 4 cases grade 2). Eighteen of 29 patients had been previously treated with melphalan in isolation perfusion (n=13) or with cisplatinum (n=2), rTNFα-Melphalan (n=1), or rTNFα alone (n=2). Median follow-up has been 41 weeks. The 29 patients are evaluable: there have been 26 (90%) complete remissions (CR), 3 (10%) partial remissions (PR), and no failures. Actuarial disease-free survival and total survival have been 63% and 73%, respectively, at 12 months. In all cases, softening of the nodules was obvious within 3 days after isolation perfusion and time to definite response ranged between day 6 and 22. This interim analysis of a phase II study suggests that high dose of rTNFα can be administered with acceptable toxicity by isolation perfusion with dopamine and hyperhydration. Tumor responses can be evidenced in all patients, with 90% CR. Furthermore, combination of rTNFα, rIFN-γ, and melphalan seems to achieve high efficacy with minimal toxicity, even after failure of prior therapy with melphalan alone. © 1992 the Société Internationale de Chirurgie.SCOPUS: ar.jinfo:eu-repo/semantics/publishe