Predictive model of Vibrio parahaemolyticus growth and survival on salmon meat as a function of temperature.

The growth and survival curves of a strain of pandemic Vibrio parahaemolyticus TGqx01 (serotype O3:K6) on salmon meat at different storage temperatures (range from 0 degrees C to 35 degrees C) were determined. In order to model the growth or inactivation kinetics of this pathogen during storage, the modified Gompertz and Weibull equations were chosen to regress growth and survival curves, respectively, and both equations produced good fit to the observed data (the average R2 value equals to 0.990 for modified Gompertz and 0.920 for Weibull equation). The effect of storage temperature on the specific growth rate (mu) was modeled by square root type equation, and the relationship between mu and lag time (lambda) was described by a rule of mu x lambda = constant. The shape factor (n) and scale factor (b) values of the Weibull equations versus the temperature (degrees C) were plotted and the temperature effects on these parameters were described by two linear empirical equations. The predicted growth and survival curves from the model were compared to real enumeration results, using the correlation coefficient (R2), bias factor (Bf) and accuracy factor (Af), to assess the performance of the established model. The results showed that the overall predictions for V. parahaemolyticus TGqx01 growth or inactivation on salmon at tested temperatures agreed well with observed plate counts, and the average R2, Bf and Af values were 0.958, 1.019 and 1.035, respectively.

[Analysis of correlation factors affecting the incidence of burn shock].

OBJECTIVE: To analyze the correlation factors affecting the incidence of burn shock, so as to provide guidance for the clinical treatment of shock after burns. METHODS: Retrospective analysis of clinical data of 15 624 patients hospitalized in our department from 1973 to 2005 was undertaken . The incidence of shock during every 10 years, as well as the relationship between shock incidence and age, burn area, interval between injury and hospitalization, and complications were analyzed statistically. RESULTS: The incidence of shock during 1973-1980, 1981-1990, 1991-2000 and 2001-2005 periods was 14.69%, 13.50%, 9.38% and 7.88%, respectively, and there was significant difference of shock incidence between each 10 years and its succeeding period (P < 0.01). The occurrence of shock was closely related to age, length of time between injury and hospitalization, and burn area. The shock incidence of children under 7 years old or elderly more than 60 years old was obviously higher than other age groups, and there was positive relationship between burn area and shock incidence. Moreover, the shock incidence of the patients hospitalized later than 4 to 12 hours after burn shock was also markedly higher than those hospitalized earlier (P < 0.01). In addition, the incidence of sepsis, alimentary tract hemorrhage, acute renal failure, pulmonary failure, and cardiac failure in patients with shock was obviously higher than those without shock (P < 0.01). CONCLUSION: For the children and aged people, special attention should be paid in the prevention and resuscitation of burn shock. Early fluid resuscitation is vital for the prevention of organ complication, and it is beneficial to promote wound healing.