Streptococcus suis remains an important challenge for the worldwide swine industry. Considering that Brazil is a major pork producer and exporter, proper monitoring of the pathogen and resistance rates are required. We present here the characterization of Brazilian S. suis strains isolated over a 15 year period by pulsed-field gel electrophoresis (PFGE) typing, capsular, virulence, and antimicrobial resistance profiling. Serotype prevalence revealed a predominance of serotype 2/ 1 2 followed by 3, 7, 1/14, 6, 8, 18, 28, and 27; the latter had not yet been reported in Brazil. Resistance profiling enabled the differentiation of nine profiles presenting resistance to three and up to eight antimicrobial classes. Even though an association between the most resistant strains and isolation year starting from 2009 was observed, a high frequency of multidrug-resistant strains isolated from 2001 to 2003 was also detected. This suggests that despite the isolation period, S. suis strains already presented high resistance selection pressure. A slight association of serotype 2/ 1 2 with some virulence profiles and PFGE pulsotypes was also identified. Nevertheless, no clonal dispersion or persistency of clones over the analyzed years and herds was detected.Pathogens 2020, 9, 31 2 of 15 shown that serotypes 20, 22, 26, 32, 33, and 34 do not belong to this species and should be classified as other bacterial species [6,7]. Moreover, novel nine capsular polysaccharide synthesis (cps) loci (NCLs) of non-typable S. suis strains have been identified based on DNA sequencing. Therefore, strict S. suis species currently comprise 38 serotypes [8].Among the virulence factors that have already been characterized in S. suis, most studied so far are the capsule, muramidase-released protein (MRP), the extracellular factor (EF), hemolysins including suilysin (SLY), plasminogen receptors, and arginine deiminase (arcA) [9].Considering antimicrobial susceptibility of S. suis strains, recent studies have described increases in resistance rates to some antimicrobial classes. Resistance to lincosamides and macrolides has been increasing, both for pigs and human strains, and resistance to sulfonamides and tetracycline showed high prevalence [8]. Resistance to cephalosporin was already described in Europe and China, but resistance prevalence to penicillin, ampicillin, and ceftiofur remains low in most countries [8,10].Emergence of multidrug resistant S. suis strains has also been described in humans and pigs, including asymptomatic animals, with highlight for the Asian epidemic clones [8]. Phenotypic and genetic studies suggest that swine may be reservoirs for the spread of antibiotic-resistant S. suis strains, which demands attention for the public health risk [8].Brazil is a major producer and exporter of pork, occupying for several years the fourth place as producer and exporter in the world [4]. This position demands attention to swine health issues. Currently, special efforts are required to reduce antimicrobial usage and monitor resistance rates ...
A eletroquimioterapia é caracterizada como um protocolo que agrega o uso de fármacos antineoplásicos à aplicação regional de pulsos elétricos, maximizando a concentração intracelular destes agentes, assim propiciando maior ação citotóxica dos mesmos. A bleomicina, um antimicrobiano dotado de propriedade antineoplásica, demonstra restrição no transporte através da membrana celular, dada sua composição molecular hidrofílica. Todavia, uma vez administrada via intralesional ou endovenosa associada à eletroporação, exibe citotoxicidade potencializada. Foram utilizados neste estudo 34 cães acometidos por neoformações solitárias de origem epitelial ou mesenquimal, situadas em pele ou membranas mucosas. Padronizou-se o protocolo eletroquimioterápico empregando-se sulfato de bleomicina, pela via intralesional, na dose de 1 U/cm³ de tumor. A eletroporação foi perfilada com eletrodo composto por agulhas, pulsos elétricos com tensão de 1000 V, em onda quadrada unipolar, com duração de 100 microsegundos, totalizando-se oito ciclos. Constatou-se remissão neoplásica integral em 30 cães (88,3%) e refratariedade ao protocolo em apenas quatro animais (11,7%). Inexistiram complicações e/ou efeitos adversos decorrentes do procedimento. O protocolo neste trabalho estudado revelou-se aplicável, eficaz e seguro na terapêutica antineoplásica em cães.
We examined the effects of hypertonic saline (HS) on inflammatory, metabolic variables, and bacterial translocation (BT) in rats submitted to intestinal obstruction and ischemia (IO). Male Wistar rats were submitted to IO and treated, 2 h thereafter, with lactated Ringer's (LR) (4 mL/kg per 5 min, i.v.) or HS (7.5% NaCl, 4 mL/kg per 5 min, i.v.). Twenty-four hours after IO, rats were also submitted to enterectomy/enteroanastomosis to resection of necrotized small bowel. Leukocyte-endothelial interactions were investigated by intravital microscopy and the expression of P-selectin and intercellular adhesion molecule 1 by immunohistochemistry. Bacterial cultures of mesenteric lymph nodes, liver, spleen, and blood were used to evaluate BT. Levels of chemokines (cytokine-induced neutrophil chemoattractants 1 and 2), insulin, and corticosterone were determined by enzyme-linked immunosorbent assay. Intestinal histology, serum urea and creatinine levels, and hepatic enzymes activities were performed to evaluate local and remote damage. Relative to IO and LR-treated rats, which exhibited increases in the number of rolling (1.5-fold), adhered (3.5-fold) and migrated (9.0-fold) leukocytes, and increased expression of P-selectin (3-fold) and intercellular adhesion molecule 1 (3-fold) on mesenteric microcirculation, treatment with HS followed by enterectomy reduced leukocyte-endothelial interactions and expression of both adhesion molecules to values attained in sham rats. Serum chemokines were normalized after treatment with both solutions followed by enterectomy. Hypertonic saline-treated rats demonstrated a significant reduction in BT to 50% in liver and spleen samples and bacteremia (14%), compared with 82% of BT in liver and spleen samples of IO and LR-treated rats and bacteremia (57%). Local intestinal damage was attenuated, and renal and hepatic function preserved by treatment with HS followed by enterectomy. Survival rate increased to 86% up to 15 days. Data presented suggest that HS solution followed by enterectomy reduces mesenteric microcirculatory dysfunctions and BT, attenuating local and remote damage in a model of strangulated small bowel obstruction.
Streptococcus suis is one of most important pathogens in the swine industry worldwide. Despite its importance, studies of S. suis characterization in South America are still rare. This study evaluates S. suis isolates from distinct Brazilian states, from 1999 to 2004, and its molecular and serological characterization. A total of 174 isolates were studied. S. suis identification was confirmed by PCR and isolates were further serotyped and genotyped by SE-AFLP and amplification of virulence markers. Serotype 1, 2, 3, 4, 7, 18, 22 and 32 were identified among the studied isolates, and only 4% were characterized as non-typeable. The mrp + /epf + /sly + genotype was the most frequent. The SE-AFLP analysis resulted in 29 patterns distributed in three main clusters with over 65% of genetic similarity. Isolates presented a slight tendency to cluster according to serotype and origin; however, no further correlation with virulence genotypes was observed.
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