Membrane Vesicles Derived from Bordetella bronchiseptica: Active Constituent of a New Vaccine against Infections Caused by This Pathogen.

Bordetella bronchiseptica, a Gram-negative bacterium, causes chronic respiratory tract infections in a wide variety of mammalian hosts, including humans (albeit rarely). We recently designed Bordetella pertussis and Bordetella parapertussis experimental vaccines based on outer membrane vesicles (OMVs) derived from each pathogen, and we obtained protection against the respective infections in mice. Here, we demonstrated that OMVs derived from virulent-phase B. bronchiseptica (OMVBbvir+) protected mice against sublethal infections with different B. bronchiseptica strains, two isolated from farm animals and one isolated from a human patient. In all infections, we observed that the B. bronchiseptica loads were significantly reduced in the lungs of vaccinated animals; the lung-recovered CFU were decreased by ≥4 log units, compared with those detected in the lungs of nonimmunized animals (P < 0.001). In the OMVBbvir+-immunized mice, we detected IgG antibody titers against B. bronchiseptica whole-cell lysates, along with an immune serum having bacterial killing activity that both recognized B. bronchiseptica lipopolysaccharides and polypeptides such as GroEL and outer membrane protein C (OMPc) and demonstrated an essential protective capacity against B. bronchiseptica infection, as detected by passive in vivo transfer experiments. Stimulation of cultured splenocytes from immunized mice with OMVBbvir+ resulted in interleukin 5 (IL-5), gamma interferon (IFN-γ), and IL-17 production, indicating that the vesicles induced mixed Th2, Th1, and Th17 T-cell immune responses. We detected, by adoptive transfer assays, that spleen cells from OMVBbvir+-immunized mice also contributed to the observed protection against B. bronchiseptica infection. OMVs from avirulent-phase B. bronchiseptica and the resulting induced immune sera were also able to protect mice against B. bronchiseptica infection.IMPORTANCEBordetella bronchiseptica, a Gram-negative bacterium, causes chronic respiratory tract infections in a wide variety of mammalian hosts, including humans (albeit rarely). Several vaccines aimed at preventing B. bronchiseptica infection have been developed and used, but a safe effective vaccine is still needed. The significance and relevance of our research lie in the characterization of the OMVs derived from B. bronchiseptica as the source of a new experimental vaccine. We demonstrated here that our formulation based on OMVs derived from virulent-phase B. bronchiseptica (OMVBbvir+) was effective against infections caused by B. bronchiseptica isolates obtained from different hosts (farm animals and a human patient). In vitro and in vivo characterization of humoral and cellular immune responses induced by the OMVBbvir+ vaccine enabled a better understanding of the mechanism of protection necessary to control B. bronchiseptica infection. Here we also demonstrated that OMVs derived from B. bronchiseptica in the avirulent phase and the corresponding induced humoral immune response were able to protect mice from B. bronchiseptica infection. This realization provides the basis for the development of novel vaccines not only against the acute stages of the disease but also against stages of the disease or the infectious cycle in which avirulence factors could play a role.

Use of Subjective Global Assessment, Patient-Generated Subjective Global Assessment and Nutritional Risk Screening 2002 to evaluate the nutritional status of non-critically ill patients on parenteral nutrition.

OBJECTIVE: To evaluate the nutritional status of non-critically ill digestive surgery patients at the moment of parenteral nutrition initiation using three different nutritional test tools and to study their correlation. To study the association between the tests and the clinical and laboratory parameters used in the follow-up of PN treatment. METHODS: Prospective study over 4 months. Anthropometric and clinical variables were recorded. Results of Subjective Global Assessment; Patient-Generated Subjective Global Assessment; and Nutritional Risk Screening 2002 were compared applying kappa test. Relationship between the clinical and laboratory parameters with Subjective Global Assessment was studied by multinominal regression and with the other two tests by multiple linear regression models. Age and sex were included as adjustment variables. RESULTS: Malnutrition in 45 studied patients varied from 51% to 57%. Subjective Global Assessment correlated well with Patient-Generated Subjective Global Assessment and Nutritional Risk Screening 2002 (κ = 0531 p = 0.000). The test with the greatest correlation with the clinical and analytical variables was the Nutritional Risk Screening 2002. Worse nutritional state in this test was associated with worse results in albumin (B = -0.087; CI = -0.169/-0.005], prealbumin (B = -0.005; CI = [-0.011/-0.001]), C-reactive protein (B = 0.006;CI = [0.001/ 0.011]) and leukocytes (B = 0.134; CI = [0.031/0.237]) at the en of parenteral nutrition treatment. CONCLUSIONS: Half of the digestive surgery patients were at malnutritional risk at the moment of initiating parenteral nutrition. Nutritional Risk Screening 2002 was the test with best association with the parameters used in the clinical follow-up of parenteral nutrition treated patients.

Objetivo: Evaluar el estado nutricional de pacientes no críticos de cirugía digestiva, en el momento de iniciar la nutrición parenteral, utilizando tres tests de evaluación nutricional. Estudiar la correlación entre los tests y su asociación con los parámetros clínicos y de laboratorio utilizados para el seguimiento de estos pacientes. Métodos: Estudio prospectivo de 4 meses. Se recogen variables antropométricas y clínicas. Los resultados de Subjective Global Assessment, Patient-Generated Subjective Global Assessment y Nutritional Risk Screening 2002 se comparan mediante test kappa. La relación entre las variables clínicas y de laboratorio con Subjective Global Assessment se estudian con regresión multinominal; y con Patient-Generated Subjective Global Assessment y Nutritional Risk Screening mediante regresión lineal múltiple. Edad y sexo se introdujeron como variables de ajuste. Resultados: La desnutrición en 45 pacientes estudiados variaba entre el 51% y el 57%. Subjective Global Assessment correlacionaba bien con Patient-Generated Subjective Global Assessment y el Nutritional Risk Screening (= 0,531 p = 0,000). Nutritional Risk Screening 2002 mostró mejor asociación con variables clínicas y analíticas: peor estado nutricional en este test se asoció con peor comportamiento de albúmina (B = -0,087; CI = -0,169/-0,005]); prealbumina (B = -0,005; CI = [-0,011/ 0,001]), proteína C reactiva (B = 0,006;CI = [0,001/0,011]) y leucocitos (B = 0,134; CI = [0,031/0,237]) al final de la nutrición parenteral. Discusión: La mitad de los pacientes de cirugía digestiva presentan algún grado de desnutrición en el momento de iniciar la nutrición parenteral. El Nutritional Risk Screening 2002 se mostró como el test con mayor relación con las variables utilizadas en el seguimiento clínico de los pacientes con nutrición parenteral.

[Susceptibility of Streptococcus pyogenes to macrolides and quinolones in Guadalajara, Spain]. / Sensibilidad de Streptococcus pyogenes a los macrólidos y las quinolonas en Guadalajara (España).

We carried out a retrospective study of the susceptibility of 104 Streptococcus pyogenes strains, which were isolated in 2000 and 2001 from clinical samples of different origins, to penicillin, erythromycin, clindamycin, ofloxacin and levofloxacin. The susceptibility testing was performed using the agar difusion method according to the guidelines of the NCCLS. All of the isolates showed susceptibility to penicillin and clindamycin. However, we detected 11 strains that were resistant to erythromycin (10.6%) and 4 strains resistant to ofloxacin (3.8%). We studied the resistance phenotypes of macrolides and lincosamides using erythromycin and clindamycin discs. Nine of the eleven strains that were resistant to erythromycin showed an M phenotype, while the remaining two showed inducible resistance to clindamycin, thus suggesting an MLS(B) inducible phenotype. No strains with constitutive resistance to erythromycin or clindamycin (MLS(B) constitutive phenotype) were identified. While penicillin is still uniformly active against S. pyogenes, in Guadalajara, there are 10.6% strains that are resistant to 14- and 15-atoms macrolides.