Streptococcal toxins: role in pathogenesis and disease

Group A Streptococcus (Streptococcus pyogenes), group B Streptococcus (Streptococcus agalactiae) and Streptococcus pneumoniae (pneumococcus) are host‐adapted bacterial pathogens among the leading infectious causes of human morbidity and mortality. These microbes and related members of the genus Streptococcus produce an array of toxins that act against human cells or tissues, resulting in impaired immune responses and subversion of host physiological processes to benefit the invading microorganism. This toxin repertoire includes haemolysins, proteases, superantigens and other agents that ultimately enhance colonization and survival within the host and promote dissemination of the pathogen.     

Characterizing hospital workers' willingness to respond to a radiological event

Introduction

Terrorist use of a radiological dispersal device (RDD, or “dirty bomb”), which combines a conventional explosive device with radiological materials, is among the National Planning Scenarios of the United States government. Understanding employee willingness to respond is critical for planning experts. Previous research has demonstrated that perception of threat and efficacy is key in the assessing willingness to respond to a RDD event.

Methods

An anonymous online survey was used to evaluate the willingness of hospital employees to respond to a RDD event. Agreement with a series of belief statements was assessed, following a methodology validated in previous work. The survey was available online to all 18,612 employees of the Johns Hopkins Hospital from January to March 2009.

Results

Surveys were completed by 3426 employees (18.4%), whose demographic distribution was similar to overall hospital staff. 39% of hospital workers were not willing to respond to a RDD scenario if asked but not required to do so. Only 11% more were willing if required. Workers who were hesitant to agree to work additional hours when required were 20 times less likely to report during a RDD emergency. Respondents who perceived their peers as likely to report to work in a RDD emergency were 17 times more likely to respond during a RDD event if asked. Only 27.9% of the hospital employees with a perception of low efficacy declared willingness to respond to a severe RDD event. Perception of threat had little impact on willingness to respond among hospital workers.

Conclusions

Radiological scenarios such as RDDs are among the most dreaded emergency events yet studied. Several attitudinal indicators can help to identify hospital employees unlikely to respond. These risk-perception modifiers must then be addressed through training to enable effective hospital response to a RDD event.     

Bodians Protargol Method Applied to Other than Neurological Preparations

Some applications of the Bodian technic for other than neurological purposes are described. After fixation for 48 hours, in formalin, 5 ml., acetic acid, glacial, 5 ml., and 80% ethyl alcohol, 90 ml., the routine procedures are recommended, with the exception that the exposure to protargol for 24 hours and subsequent reduction should be repeated once. Gold toning may be o-mitted. With this method the argentaffin (chromaffin) cells of the digestive tract (rat, hamster), the alpha cells of the pancreatic islands (hamster) and the medullary cells of the suprarenal gland (hamster) are selectively impregnated. In the mammalian pituitary gland (rat, hamster) certain of the granulated chromophile cells are impregnated. In the rat only the basophiles appear to react with the silver.