Exposure of periodontal ligament progenitor cells to lipopolysaccharide from Escherichia coli changes osteoblast differentiation pattern

Periodontal ligament mesenchymal stem cells (PDLMSCs) are an important alternative source of adult stem cells and may be applied for periodontal tissue regeneration, neuroregenerative medicine, and heart valve tissue engineering. However, little is known about the impact of bacterial toxins on the biological properties of PDLSMSCs, including self-renewal, differentiation, and synthesis of extracellular matrix. Objective : This study investigated whether proliferation, expression of pro-inflammatory cytokines, and osteogenic differentiation of CD105-enriched PDL progenitor cell populations (PDL-CD105+ cells) would be affected by exposure to bacterial lipopolysaccharide from Escherichia coli (EcLPS). Material and Methods : Toll-like receptor 4 (TLR4) expression was assessed in PDL-CD105+ cells by the immunostaining technique and confirmed using Western blotting assay. Afterwards, these cells were exposed to EcLPS, and the following assays were carried out: (i) cell viability using MTS; (ii) expression of the interleukin-1 beta (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor alpha (TNF-α) genes; (iii) osteoblast differentiation assessed by mineralization in vitro, and by mRNA levels of run-related transcription factor-2 (RUNX2), alkaline phosphatase (ALP) and osteocalcin (OCN) determined by quantitative PCR. Results : PDL-CD105+ cells were identified as positive for TLR4. EcLPS did not affect cell viability, but induced a significant increase of transcripts for IL-6 and IL-8. Under osteogenic condition, PDL-CD105+ cells exposed to EcLPS presented an increase of mineralized matrix deposition and higher RUNX2 and ALP mRNA levels when compared to the control group. Conclusions : These results provide evidence that CD105-enriched PDL progenitor cells are able to adapt to continuous Escherichia coli endotoxin challenge, leading to an upregulation of osteogenic activities. .

Investigation of Positive Streptococcus pneumoniae Urinary Antigen Test Results in a Korean University Hospital / 대한임상미생물학회지

BACKGROUND: The Streptococcus pneumoniae urinary antigen test (SPUAT) (Binax Now, USA) was developed for detecting polysaccharide C in urine samples for rapid diagnosis of pneumococcal pneumonia, the most common cause of community-acquired pneumonia (CAP). To validate positive results of these tests, we retrospectively investigated all positive results obtained from the emergency room of a Korean university hospital among patients with suspected CAP. METHODS: One hundred twenty-three positive SPUAT results were abstracted and analyzed from the authors' laboratory information system among the SPUAT results performed from 1,143 pneumonic patients admitted from the emergency room of a university hospital between 2007 and 2008. Medical records, including conventional microbiologic analysis results, were reviewed in detail for all positive test results. RESULTS: Among 123 patients with the positive SPUAT results, 24 patients were excluded due to hospitalization history during the preceding month. Nine of 99 patients (9.1%) with suspected CAP had confirmed pneumococcal pneumonia upon conventional sputum or blood culture. Thirty-five positive results (35.4%) showed other microorganisms upon conventional methods, which might be due to possible cross-reactivity. Among those, 23 positive results were considered bacterial pneumonic agents, and 12 positive results were regarded as urinary tract infection strains or contaminating agents. Fifty-five positive SPUAT results (55.6%) showed negative conventional microbiologic growth, and some positive SPUAT results might be caused by true pneumococcal infection although without cultural evidence. CONCLUSION: Our retrospective study demonstrated that a positive SPUAT result typically does not agree well with conventional culture methods, suggesting that the value of a positive SPUAT result in etiology determination may be limited under practical conditions in a university hospital.

Obtenção de antitoxina perfringens do tipo A em escala industrial / Production of perfringens antitoxin type A in industrial scale

Descreve-se o método utilizado na preparação da antitoxina perfríngica do tipo A, em escala industrial, pela hiperimunização de cavalos, através de antígeno misto, adsorvido pelo alúmen de potássio. Empregando-se esquema de imunização próprio, conseguiu-se obter soro antigangrenoso perfríngico tipo A, dosando ao redor de 200 UI/ml, título este que, após a concentração pelo método de Pope, elevou-se ao nível antitóxico de 850 a 1.000 UI/ml. O soro purificado e concentrado foi diluído convenientemente para compor o soro antigangrenoso polivalente (AU).

A method is described for the preparation of Clostridium perfringens type A antitoxin,on industrial scale, by the hyperimmunization of horses with mixed alum-adsorbed antigen. With the use of the immunization method idealized in laboratory of Instituto Butantan, São Paulo, an antigangrenous Cl. perfringens type A antitoxin was obtained with a dosage of about 2'00 lU Iml,a titrethatafterconcentrationby .Pope'smethod,increasedto antitoxicIevelsof850to 1.000 lU Iml. The purified and concentrated antitoxin was conveniently diluted to constitute a polyvalent gas gangrene antitoxin. (AU)

Ocorrência da dissociação somática em Salmonella do sorogrupo E. (Nota prévia) / Occurrence of somatic dissociation in Salmonella of serogroup E. (Previous note)

É relatado pela primeira vez em nosso meio o encontro da dissociação somática em 4 cepas de Salmonella sp. do grupo E, isoladas de ração de aves, submetidas a exame no Laboratório I do Instituto Adolfo Lutz em Campinas, SP... (AU).