Residents can be trained to detect abdominal aortic aneurysms using personal ultrasound imagers: a pilot study.

Our objective was to test the hypothesis that internal medicine residents can be trained to screen for abdominal aortic aneurysm (AAA) using personal ultrasound imagers. We trained 5 randomly chosen internal medicine residents to image the abdominal aorta for patients with risk factors for AAAs using personal ultrasound imagers. Residents were trained in 3 or 4 one-on-one sessions with an instructor. To be eligible, patients had to be older than 65 years and have hypertension. After training, each of the 5 residents studied 3 patients independently. In 12 of the residents' 15 unsupervised studies, their abdominal aorta measurements were within 5 mm of the instructor's measurements with standard echocardiography (mean difference 3 mm, range 0-6 mm). Residents detected 3 previously unknown AAAs measuring 5.2, 4.2, and 3.9 cm in diameter. We conclude residents can be trained to image the abdominal aorta with personal ultrasound imagers and to identify AAAs in patients at risk.     

Manipulating prefabricated flaps: An experimental study examining flap viability

As flap prefabrication becomes a more commonly used clinical tool, it is necessary to investigate the limitations of this technique. Reconstructive procedures of the face often require “custom fitted” flaps to satisfy esthetic demands. This study examines and compares the safety of manipulating thin prefabricated skin flaps versus established axial pattern skin flaps. Twenty-seven New Zealand white rabbits were used to determine if prefabricated flaps can be folded 180° around the edge of the rabbits' ears. The survival of these folded prefabricated flaps was compared with the survival of axial pattern flaps sutured into an identically recipient site. In addition, flaps prefabricated in the same manner were sutured onto a straight recipient bed to evaluate the viability of the newly vascularized tissue. The folded prefabricated flaps had reduced survival (56%) compared to equivalent folded axial pattern flaps (85%), P<0.005. The nonmanipulated prefabricated flaps and axial pattern flaps survived completely. © 1994 Wiley-Liss, Inc.     

Undifferentiated nasopharyngeal carcinoma presenting as a parotid mass

Background. Nasopharyngeal carcinoma has a variety of presentations. However, in more than 50% of cases it may present with serous otitis or cervical metastases. Although the metastases usually occur in the neck, the lymphatic network of the parotid may also serve as a site for the metastatic deposits. We present a case in which the initial manifestation of nasopharyngeal carcinoma of the lymphoepithelioma type was a parotid mass. Methods. Case study. Results. A patient who was initially seen with an isolated parotid mass was found to have an undifferentiated carcinoma of the lymphoepithelial type. Further evaluation identified an occult nasopharyngeal carcinoma, and the patient underwent radiotherapy. Conclusions. A diagnosis of a malignant lymphoepithelial lesion of the parotid gland or undifferentiated carcinoma of the lymphoepithelial type mandates a search for an occult primary nasopharyngeal tumor.     

Patterns of allele losses suggest the existence of five distinct regions of loh on chromosome 17 in breast cancer

Chromosome 17 is a frequent target during breast-cancer formation and progression. It has been shown to be affected by allele losses at multiple sites, as well as by DNA amplification. Our aim was to delineate a map of the genetic alterations on chromosome 17 in a given set of breast tumors. To this end we analyzed 151 pairs of tumor and cognate lymphocyte DNAs by Southern blotting with 5 RFLP or VNTR probes and by PCR at 8 CA repeat polymorphic loci for LOHs. Moreover, we studied DNA amplification of the evi2, erbB2, thra1, gcsf and rara genes. Data presented here point strongly to the existence of 5 distinct regions of allele losses on chromosome 17:2 on 17p, 3 on 17q. Of the 2 regions on 17p, one involves tp53 while the second is located more distally toward the telomere. LOH was found in 45.9% and 58.8% respectively. The 3 regions on 17q are located: (i) on the proximal portion of the long arm band q21, corresponding to the brcal region; (ii) in a central region defined by the marker D17S74; (iii) on the distal part of 17q (band q25) characterized by losses of the marker D17S24. Each of these regions presented respectively allele losses in 47.5%, 33.3% and 40.8% of the informative tumors. Whereas some tumors presented patterns of LOH consistent with the loss of a complete chromosomal arm or of large portions of the chromosome, a high proportion of the analyzed tumors showed interstitial losses. Amplifications were found in 15% of the tumors and were centered around erbB2. An altered chromosome 17 (bearing an LOH or a DNA amplification) was found in more than 80% of the breast tumor set analyzed here and multiple anomalies affecting this chromosome were often detected in the same sample.     

Diffusion‐Weighted MRI in Creutzfeldt‐Jakob Disease: A Better Diagnostic Marker Than CSF Protein 14‐3‐3?

Two middle-aged patients presented with rapidly progressive dementia and ataxia, nonspecific electroencephalography findings, and negative cerebrospinal fluid (CSF) protein 14-3-3. Both patients underwent brain magnetic resonance imaging (MRI) scans that demonstrated abnormalities on diffusion-weighted imaging (DWI) sequences, and both were later confirmed to have Creutzfeldt-Jakob disease. (CJD) by tissue examination. Because a recent position paper from the American Academy of Neurology characterized CSF protein 14-3-3 as a gold standard for clinically diagnosing CJD, the authors reviewed studies of CJD in which DWI-MRI imaging and CSF protein 14-3-3 studies were both performed. Among 19 reported cases of CJD with DWI-MRI lesions, CSF protein 14-3-3 was negative in 6 cases and positive in 2 others. The authors' findings suggest that multifocal cortical and subcortical hyperintensities confined to gray matter regions in DWI-MRI may be a more useful noninvasive diagnostic marker for CJD than CSF protein 14-3-3. These observations provide a compelling rationale for a prospective comparative study.     

Synaptic potentials and effects of amino acid antagonists in the auditory cortex

Neurons of in vitro guinea pig and rat auditory cortex receive a complex synaptic pattern of afferent information. As many as four synaptic responses to a single-stimulus pulse to the gray or white matter can occur; an early-EPSP followed, sequentially, by an early-IPSP, late-EPSP, and late-IPSP. Paired pulse stimulation and pharmacological studies show that the early-IPSP can modify information transmission that occurs by way of the early-EPSP. Each of these four synaptic responses differed in estimated reversal potential, and each was differentially sensitive to antagonism by pharmacological agents. DNQX (6,7-dinitroquinoxaline-2,3-dione), a quisqualate/kainate receptor antagonist, blocked the early-EPSP, and the late-EPSP was blocked by the NMDA receptor antagonist APV (D-2-amino-5-phosphonovalerate). The early-IPSP was blocked by the GABA-a receptor antagonist bicuculline, and the late-IPSP by the GABA-b receptor antagonists 2-OH saclofen or phaclofen. Presentation of stimulus trains, even at relatively low intensities, could produce a long-lasting APV-sensitive membrane depolarization. Also discussed is the possible role of these synaptic potentials in auditory cortical function and plasticity.     

Variable Disposition of Ciprofloxacin in Critically Ill Patients Undergoing Continuous Arteriovenous Hemodiafiltration

Continuous arteriovenous hemodiafiltration (CAVHD) is being used increasingly in critically ill patients with acute renal failure (ARF). We prospectively evaluated extracorporeal and total systemic clearances (Cl_CAVHD and Cl_s) of ciprofloxacin during CAVHD in four patients with severe ARF to assess the adequacy of drug dosing. Ciprofloxacin serum and ultrafiltrate concentrations were measured by high-performance liquid chromatography. The Cl_CAVHD accounted for approximately 5.9% (range 2.8–11.6%) of Cl_s of ciprofloxacin. However, large variability in serum concentrations was observed with the normally recommended dose of 400 mg/day, and doses of up to 800 mg/day were required to maintain concentrations suitable for treatment of serious infections. High daily doses of ciprofloxacin required in these patients are likely related to altered pharmacokinetics in serious illness as well as to the increased extracorporeal clearance during CAVHD. Clinical studies to define appropriate dosing recommendations for ciprofloxacin during CAVHD are necessary to guide clinicians in optimum drug use.