Atrial natriuretic peptide expression is increased in rat cerebral cortex following spreading depression: possible contribution to sd-induced neuroprotection

Cortical spreading depression (CSD) is characterised by slowly propagating waves of cellular depolarization and depression and involves transient changes in blood flow, ion balance and metabolism. In cerebral ischaemia, peri-infarct CSD-like depolarization potentiates infarct growth, whereas preconditioning with a CSD episode protects against subsequent ischaemic insult. Thus, many of the long-lasting molecular changes that occur in CSD-affected tissue are presumed to be part of a 'neuroprotective cascade.' 3',5'-Cyclic guanosine monophosphate (cGMP) has been shown to be a neuroprotective mediator and the nitric oxide system, which increases cGMP production by soluble guanylate cyclase, is up-regulated by CSD. Atrial and C-type natriuretic peptide (ANP/CNP) are present in cerebral cortex and their actions are mediated via particulate guanylate cyclase receptors and cGMP production. Therefore, in further efforts to characterise the role of cGMP-related systems in CSD and neuroprotection, this study investigated possible changes in cortical natriuretic peptide expression following acute, unilateral CSD in rats. Using in situ hybridisation, significant 20-80% increases in ANP mRNA were detected in layers II and VI of ipsilateral cortex at 6 h and 1-14 days after CSD. Ipsilateral cortical levels were again equivalent to control contralateral values after 28 days. Assessment of cortical concentrations of ANP immunoreactivity by radioimmunoassay revealed a significant 57% increase at 7 days after CSD. Despite using a sensitive signal-amplification protocol, authentic ANP-like immunostaining was readily detected in subcortical nerve fibres, but was not reliably detected in normal or CSD-affected neocortex, suggesting the presence of very low levels, and/or active or differential processing of the peptide. Cortical CNP mRNA levels are not altered by CSD, indicating the specificity of the observed effects.Overall, these novel findings demonstrate a prolonged increase in cortical ANP expression after an acute episode of CSD. The overlap between the described time course of CSD-induced protection against ischaemic insult and demonstrated increases in ANP levels, suggest that ANP (like nitric oxide) may contribute to CSD-induced neuroprotection, via effects on cGMP production and other signal-transduction pathways.     

Earring lesions of the parotid tail

BACKGROUND AND PURPOSE: Masses in the parotid tail can be a source of consternation to radiologists and clinicians; inaccurate localization may lead to significant iatrogenic complication. We sought to review the pertinent anatomic localizing features of the parotid tail, relevant facial nerve anatomy, and sources of clinical and radiologic confusion. To conclude, we review imaging features that are helpful in generating a diagnosis in this location. METHODS: We retrospectively reviewed the imaging and clinical features of 111 parotid tail masses in 103 patients (56 male, 45 female, two of unknown sex; age range, 5 months-81 years). The following imaging findings were noted: size, enhancement, multiplicity of lesions, attenuation on CT scans, signal intensity on MR images, and appearance of the surrounding parotid gland. Diagnosis was confirmed by either surgical resection or biopsy findings or by specific clinical data or characteristic imaging findings. RESULTS: Seventeen types of parotid tail masses were identified. Benign lesions were: pleomorphic adenoma (n = 15), Warthin tumor (n = 14), infectious process (n = 13), venous malformation (n = 9), and Sj?gren disease (n = 9), lymphatic malformations (n = 7), lipoma (n = 6), HIV lymphoepithelial lesion (n = 4), first brachial cleft cyst (n = 3), oncocytoma (n = 2), sarcoid (n = 1), and lymph node (n = 1). Malignant lesions were: Non-Hodgkin lymphoma (n = 14), metastatic disease (n = 7), mucoepidermoid carcinoma (n = 4), acinic cell carcinoma (n = 1), and undifferentiated carcinoma (n = 1). Eight patients had two diagnoses. CONCLUSION: Understanding normal parotid tail anatomy is important to radiologists, because accurate localization has implications for appropriate management of masses in this location, potentially reducing the occurrence of marginal mandibular nerve injury.     

Computerized Scientific Exhibit Utilization: Observations From infoRAD at the Radiologic Society of North America Scientific Assembly

No publication has discussed utilization of computer scientific exhibits (CSE) at national symposia, despite their growing numbers. The hypothesis of this project was that, when given a choice, viewers initially would prefer a more conventional paper presentation of a scientific exhibit over that of an electronic presentation. A nearly identical paper version of the introductory screen to an infoRAD CSE was placed adjacent to the workstation. Utilization of the paper introduction, computer introduction, and both, as well as subsequent behavior, was recorded. Of 67 visitors, initial user choice was 56.7% paper and 43.3% computer. Over the entire time at the exhibit 25.4% only looked at the handout, 25.4% only at the computer, and 49.3% perused both. Only 10.5% completed the entire exhibit, and 0.94% of total registrants visited the CSE. Overall, 74.7% perused the CSE when leaving the exhibit area. Upon arrival, viewers preferred the more conventional paper presentation, confirming the project hypothesis. Surprisingly, about 75% eventually perused at least a portion of the computer presentation. Although a small fraction of Radiologic Society of North America (RSNA) registrants visited the CSE, the findings presented are promising and suggest that CSE presence at national meetings is justifiable, providing a "first step" toward CME outcomes analysis of CSE. Overall, these findings are promising and suggest that computer scientific exhibit presence at national meetings is justifiable.     

Agromedicine focus group: cooperative extension agents and medical school instructors plan farm field trips for medical students

BACKGROUND: Current medical education policy seeks to address the health care needs of underserved populations, among whom are individuals associated with agriculture. METHODS: This paper describes a focus group approach to planning farm field trips whereby medical students accompany agricultural extension agents to study the personal, occupational, and environmental health concerns of farmers. RESULTS: The resulting plan joins a state's cooperative extension system, medical school, and farm community in partnership to provide an experiential approach to agricultural medicine and rural health education. CONCLUSION: The planning exercise and the field trips are successful examples of agromedicine, a partnership approach to preventive agricultural medicine involving professionals in medicine and in agriculture.     

Hepatic perfusion index and the evolution of liver metastases

A total of 150 patients with primary carcinoma of the gastrointestinal tract had first-pass technetium colloid scintigraphy to estimate the hepatic perfusion index (HPI). Postoperative follow-up over 2-4 years shows that the HPI remains a sensitive method of detecting hepatic metastases, even in patients whose liver appeared normal at laparotomy. HPI was elevated in 94% of patients with liver metastases found at laparotomy; 87% of patients with occult metastases which became overt within 3 years of surgery had elevated HPI; and 91% of all patients who have to date developed hepatic metastases had elevated HPI at presentation. Of all patients with elevated HPI, 82% had metastases which were either apparent at surgery or became detectable by other means within 3 years.     

Doing being 'on the edge': managing the dilemma of being authentically suicidal in an online forum

Those who attempt suicide have often been described as 'crying for help', and there are implications if such cries are not taken seriously. This paper examines how users of an Internet forum for 'suicidal thoughts' work up their authenticity in their opening posts, and how these are responded to by fellow forum users. Data were taken from two Internet forums on suicide over a period of one month and were analysed using discursive psychology. The analysis demonstrates that participants display their authenticity through four practices: narrative formatting, going 'beyond' depression, displaying rationality and not explicitly asking for help. Furthermore, both initial and subsequent posts worked up identities as being psychologically 'on the edge' of life and death. The analysis suggests that the forum in part works as a site for suicidal identities to be tested out, authenticated and validated by individuals. We conclude with some suggestions for the supportive work of suicide 'postvention'.     

Using popular education for community empowerment: perspectives of Community Health Workers in the Poder es Salud/Power for Health program

Empowerment has been advanced as a strategy for eliminating remaining health disparities. Popular education promotes community empowerment by increasing individuals’ and communities’ awareness of their capacity and providing a framework and strategies through which participants can identify and resolve problems. Poder es Salud/Power for Health, a community-based participatory research project, sought to improve health and decrease disparities in African American and Latino communities in Multnomah County, Oregon, through the intervention of Community Health Workers (CHWs) who used popular education. In-depth interviews were conducted with five CHWs involved in the project to explore their perceptions of the effects of the use of popular education on the CHWs and their communities. Results suggested that CHWs possessed a shared understanding of popular education. Effects on the CHWs included increases in community participation and identification, desire to advocate for the community, and sense of personal potential. Similarly, among communities, CHWs observed increases in level of participation in community events, quality and quantity of leadership, and sense of community solidarity. These results suggest that popular education, when used consistently throughout a health promotion program, can promote empowerment and thus contribute to eliminating health disparities.