The application of ultraviolet germicidal irradiation to control transmission of airborne disease: bioterrorism countermeasure

Bioterrorism is an area of increasing public health concern. The intent of this article is to review the air cleansing technologies available to protect building occupants from the intentional release of bioterror agents into congregate spaces (such as offices, schools, auditoriums, and transportation centers), as well as through outside air intakes and by way of recirculation air ducts. Current available technologies include increased ventilation, filtration, and ultraviolet germicidal irradiation (UVGI) UVGI is a common tool in laboratories and health care facilities, but is not familiar to the public, or to some heating, ventilation, and air conditioning engineers. Interest in UVGI is increasing as concern about a possible malicious release of bioterror agents mounts. Recent applications of UVGI have focused on control of tuberculosis transmission, but a wide range of airborne respiratory pathogens are susceptible to deactivation by UVGI. In this article, the authors provide an overview of air disinfection technologies, and an in-depth analysis of UVGI-its history, applications, and effectiveness.     

An experimental method for teaching research to graduate nursing students

This article provides a creative and interactive method for teaching a metaparadigm of inquiry that values and embraces both naturalistic and positivistic approaches to research. The author outlines an experiential method for teaching graduate level research that blends opportunities to meet the needs of students with either global or analytic information processing styles, as well as varying student learning styles. The method involves a semester-long journey whereby students cognitively and viscerally begin to understand the interconnectedness of all research knowledge, and consists of five elements: 1) creating a nonthreatening environment; 2) using guided imagery; 3) teaching research along the "Continuum of Inquiry"; 4) take-home and midterm exams based on hypothetical clinical situations; and (5) developing a written research proposal.     

Medication use and falls in community-dwelling older persons

BACKGROUND: The association between injurious falls requiring a visit to the emergency department and various classes of medications was examined in a case-control study of community living persons aged 66 years and older. METHODS: Administrative databases from an urban health region provided the information used. Five controls for each case were randomly selected from community dwelling older persons who had not reported an injurious fall to one of the six regional emergency departments in the study year. Two series of analyses on medication use within 30 days of the fall were conducted using logistic regression, the first controlling for age, sex, and median income, the second controlling for co-morbid diagnoses as well. RESULTS: During the study year there were 2,405 falls reported by 2,278 individuals to six regional emergency departments giving a crude fall rate of 31.6 per 1,000 population per year. The initial analysis identified seven medication classes that were associated with an increased risk of an injurious fall, while controlling for age, gender and income. However, with further analyses controlling for the additional effects of co-morbid disease, narcotic pain-killers (odds ratio 1.68), anti-convulsants (odds ratio 1.51) and anti-depressants (odds ratio 1.46) were significant independent predictors of sustaining an injurious fall. CONCLUSION: These results are based on a Canadian population-based study with a large community sample. The study found that taking certain medications were independent predictors of sustaining an injurious fall in our elderly population - in addition to the risk associated with their medical condition.     

Variant Creutzfeldt-Jakob disease

Variant CJD is a novel human prion disease that represents the first known occasion in which animal prion diseases have been transmitted to humans. There are many uncertainties concerning vCJD, including the mechanism of transmission between species, the extent of human exposure to the BSE agent, the infectious dose for humans, and the future burden of human disease. It is hoped that continuing scientific research may lead to answers to some of these questions and that further understanding of the mechanism of prion replication may lead to the development of effective treatment. Indeed a recent publication has suggested that the drugs quinacrine or chloropromazine may be candidates for the treatment of human prion diseases [42].     

Requiring help injecting as a risk factor for HIV infection in the Vancouver epidemic: implications for HIV prevention

BACKGROUND: Requiring help injecting was recently associated with syringe sharing, and later HIV-1 and HCV seroconversion among injection drug users (IDU) in Vancouver. This risk factor remains poorly understood. The present study investigates this risk factor among Vancouver IDUs. METHODS: We evaluated factors associated with requiring help injecting among participants enrolled in the Vancouver Injection Drug User Study (VIDUS) using univariate and logistic regression analyses. VIDUS participants who were followed-up during the period December 2000 to December 2001 were eligible for the present analyses. We also evaluated self-reported reasons for requiring help injecting. RESULTS: Overall, 661 active injection drug users were interviewed during the study period. Among this population, 151 (22.8%) had required help injecting during the last six months, whereas 510 (77.2%) indicated that they had not. Variables that were independently associated with requiring help injecting included borrowing a used syringe (adjusted odds ratio [AOR] = 2.18), frequent cocaine injection (AOR = 1.57), and female gender (AOR = 2.29). Among males, the most common reasons for requiring help injecting were: having no viable veins (77.1%), and anxiousness or being drug sick (42.9%). Among females, the most common reasons reported were: having no viable veins (71.6%), jugular injection or 'jugging' (45.7%), and being anxious or drug sick (27.2%). Almost twice as many females (13.6% vs 7.1%) reported not knowing how to inject as their reason for requiring help injecting. CONCLUSION: Although current public health approaches, such as needle exchange, are unable to address the concerns associated with requiring help injecting, available evidence suggests that safer injecting facilities have the potential to substantially mitigate this risk behaviour.     

Fine-needle aspiration features of pilomatrixoma

BACKGROUND: Pilomatrixoma (PMX) is a benign skin neoplasm of hair matrix origin. The fine-needle aspiration (FNA) features of PMX frequently lead to a misdiagnosis of carcinoma. METHODS: Nine cases of PMX in which a preoperative FNA was performed were reviewed. The cytologic features were compared with the histologic appearance of corresponding surgical specimens as well as with cytologic features of tumors that arose in the differential diagnosis. RESULTS: Unequivocal benign diagnoses were rendered in three cases; the correct preoperative diagnosis of PMX was rendered in two of these cases and considered in an additional case. In four additional cases, carcinoma was diagnosed or could not be excluded. A noncommittal diagnosis of epithelial tumor, most likely of skin adnexal origin, was rendered in an additional single case. Retrospective review of the FNA smears in all nine instances disclosed cytologic features that corresponded well with the histologic components of PMX. Diagnostic cytologic features included cellular aspirates; clusters of small, primitive-appearing basaloid epithelial cells; a high nuclear-cytoplasmic ratio; evenly dispersed chromatin; prominent nucleoli; pink, fibrillary material enveloping clusters of basaloid cells; multinucleated giant cells; and sheets of ghost cells. CONCLUSIONS: The FNA cytologic diagnosis of PMX may be extremely difficult; its distinction from various primary cutaneous carcinomas is most problematic. Recognition of a unique constellation of cytologic features in FNA smears in the appropriate clinical context is most helpful in making this distinction.     

Recording of diabetes on death certificates. Has it improved?

OBJECTIVE: To determine whether the recording of diabetes on death certificates improved from 1986 to 1993. METHOD: Comparison of two National Mortality Follow-back Surveys that selected independent samples of death certificates with the purpose of obtaining information from informants about the decedents. RESULTS: The recording of diabetes on death certificates did not improve from 1986 to 1993. CONCLUSION: Periodic monitoring of the accuracy of death certificates is essential for proper interpretation of mortality statistics which are routinely used to describe the burden of diabetes in our society.     

Novel animal models of affective disorders

Is there an appropriate animal model for human affective disorders? The traditional difficulties in accepting animal models for psychopathology stem from the argument that there is no evidence for concluding that what occurs in the brain of the animal is equivalent to what occurs in the brain of a human. However, if one models any or some core aspects of affective disorder, this model can become an invaluable tool in the analysis of the multitude of causes, genetic, environmental, or pharmacological, that can bring about symptoms homologous to those of patients with affective disorders. Animal models can also allow the study of the mechanisms of specific behaviors, their pathophysiology, and can aid in developing and predicting therapeutic responses to pharmacologic agents. Although animals exhibit complex and varied social and emotional behaviors for which well-validated and standardized measures exist, an understanding that a precise replica of human affective disorders cannot be expected in a single animal model is crucial. Instead, a good animal model of a human disorder should fulfill as many of the four main criteria as possible: (1) strong behavioral similarities, (2) common cause, (3) similar pathophysiology, and (4) common treatment. An animal model fulfilling any or most of these criteria can be used to elucidate the mechanisms of the specific aspect of the model that is homologous to the human disorder. A wide range of animal models of affective disorders, primarily depression, has been developed to date. They include models in which "depressive behavior" is the result of genetic selection or manipulation, environmental stressors during development or in adulthood, or pharmacologic treatments. The assessment of these animal models is based either on behavioral tests measuring traits that are homologous to symptoms of the human disorder they model, or behavioral tests responsive to appropriate pharmacologic treatments. The goal of this review is to focus on relatively recent developments of selected models, to aid in understanding their strengths and weaknesses, and to help those choosing the difficult task of developing novel animal models of affective disorders. The ideal animal model of affective disorders of the future would be an endogenous, genetic model that reiterates the essential, core aspects of the human disease and responds to the standard regimens of therapy. Because complex diseases have been approached from the genetic startpoint by using rodent models, a genetic model of affective disorder would open up possibilities for genetic analysis of polygenic traits that seem to underlie these disorders.