Acute ischemic stroke review.

More than 700,000 people have a stroke each year in the United States. A diagnosis of stroke formerly elicited a nihilistic approach, but this has substantially changed in the last decade. Currently, time is brain, and it is important for all disciplines to work together to initiate acute stroke protocols in the emergency department and identify patients within the therapeutic time window for thrombolytic and neuroprotective therapies. Evolving protocols, management, and nursing care all have important implications during the acute phase of ischemic stroke. Patient and family education on risk reduction must also be addressed by the entire healthcare team.     

Effects of improved contrast on lung-nodule detection. A clinical ROC study

We evaluated the effects of unsharp masking and highly efficient scatter rejection on film-screen chest radiographs of cancer patients. Unsharp masking significantly improved the detectability of lung nodules and visibility of anatomic structures in poorly penetrated areas of the chest. Highly efficient scatter rejection by an improved antiscatter grid provided only modest additional benefits. The study supports the conclusion that nodule detection in poorly penetrated areas on conventional chest radiographs is limited primarily by display contrast, whereas in the well-penetrated lung fields it is limited primarily by confusing background structures, rather than inadequate contrast. A method for analyzing clinical nodule detection data by transforming the FROC data to ROC coordinates also is demonstrated.     

Therapist features in sexual offender treatment: their reliable identification and influence on behaviour change

In the first of the two studies reported here, we established that trained judges could reliably identify 18 therapist features that occurred with reasonable frequency. In the second study 17 of these features were examined to determine how well they related to changes in sexual offenders with treatment. Five videotapes from each of five different prison programs were rated for the presence of these 17 features and correlational analyses examined their relationship with changes in 44 measures of treatment targets. The primary findings indicated that empathy and warmth displayed by the therapists and their directive and rewarding behaviours, were the features that most strongly predicted therapeutic benefits. The results are discussed in terms of their clinical and research implications. Copyright © 2002 John Wiley & Sons, Ltd.     

Transient transfection of the enteric parasite Entamoeba histolytica and expression of firefly luciferase.

Development of DNA-mediated transfection in Entamoeba histolytica will facilitate basic research toward the control of this protozoan parasite. A transient transfection system was established by using the firefly luciferase gene ligated to the 5' and 3' flanking regions of the amebic hgl1 gene. The optimal construct tested encoded an hgl1-luciferase fusion protein and contained 1 kb of 5' flanking sequence with 16 bases of coding sequence from the hgl1 gene ligated in-frame to the luciferase start codon and 2.3 kb of 3' flanking sequence from hgl1 ligated 3' to the luciferase stop codon. Optimal electroporation conditions in strain HM-1:IMSS trophozoites when using this construct were 500 microF and 500 V/cm, which resulted in luciferase activity up to 5000-fold above background 9-12 hr after electroporation. Constructs that contained the luciferase gene without amebic flanking sequences or that contained a simian virus 40 promoter, enhancer, and polyadenylylation signal produced only background levels of luciferase activity. The ability to introduce and express genes in amebae will now permit a genetic analysis of the virulence of this organism, which remains a serious threat to world health.     

Vascular production and regulation of angiotensin

To test the hypothesis that angiotensin (Ang) I and II are produced by blood vessels, we investigated the formation of both Ang I and Ang II in isolated, perfused rat hindquarters. To characterize the nature of this production further, we modulated plasma renin by total or subtotal nephrectomy and tested the effects of exogenous renin and renin substrate on vascular Ang formation. Assays of the perfusate by high-performance liquid chromatography and radioimmunoassay demonstrated the spontaneous release of Ang I and Ang II from the hindlimb vasculature. Conversion of Ang I to Ang II in hindquarter vasculature was approximately 75% and was totally suppressed by captopril. The spontaneous formation of Ang peptides was abolished by bilateral nephrectomy but was not affected by subtotal 5/6 nephrectomy. The addition of purified rat angiotensinogen to the preparation increased Ang II levels. The infusion of renin into the hindlimb vasculature led to substantial increases in local Ang formation and also raised the perfusion pressure. Both effects were sensitive to captopril and to the renin inhibitor H-142. The data indicate that Ang I and Ang II are produced locally within blood vessels. However, the origin of vascular renin remains controversial. Our results suggest that part of the enzyme is taken up from plasma.     

Brainstem Evoked Response audiometry in diabetes mellitus

This study was undertaken to record the Brainstem Evoked Responses in a group of 20 diabetic patients with normal hearing and were compared with responses of another group of 20 normal individuals. Eighth nerve transmission till the level of cochlear nucleus was found to be normal in diabetics. The delay in latency of Wave III, IV and V and interpeak latencies (I–III, I–V) were noted to be statistically significant, thus suggesting the presence of central neuropathy in patients with diabetes. No significant sex difference on latency of waves was observed.     

Effects of residence and race on burden of travel for care: cross sectional analysis of the 2001 US National Household Travel Survey

Background  

Travel burden is a key element in conceptualizing geographic access to health care. Prior research has shown that both rural and minority populations bear disproportionate travel burdens. However, many studies are limited to specific types of patient or specific locales. The purpose of our study was to quantify geographic and race-based differences in distance traveled and time spent in travel for medical/dental care using representative national data.     

Rational approaches to the neurobiologic study of youth at risk for bipolar disorder and suicide

Objectives:  The aims of this paper are to provide an overview of neuroimaging findings specific to bipolar disorder and suicide, and to consider rational approaches to the design of future in vivo studies in youth at risk.
Methods:  Neuroimaging and related neurobiological literature pertaining to bipolar disorder and suicide in adult and pediatric samples was reviewed in a non-quantitative manner.
Results:  Specific structural and functional brain findings in bipolar disorder are described, where possible in the context of relevant current neurobiological theories of etiology. Diagnostic and prognostic implications are discussed.
Conclusions:  The simultaneous use of complementary neurobiological approaches may be a powerful way of identifying and validating factors reliably associated with bipolar disorder and suicide. A profile of neurobiological markers with which to screen for bipolar disorder and suicide risk may provide for earlier and more accurate diagnosis, perhaps even in the pre- or subsyndromal stages in high-risk youth.