Renovascular hypertension: anatomic and renal function changes during drug therapy

Serial renal function studies were performed on 41 patients wtih renovascular hypertension (RVH) secondary to atherosclerotic renal artery disease who had been randomly selected for nonoperative management. In 19 patients, serum creatinine levels increased between 25% and 120%. The glomerular filtration rates dropped between 25% and 50% in 12 patients. Fourteen patients (37%) lost more than 10% of renal length. In four patients (12%), a significant stenosis progressed to total occlusion. Seventeen patients (41%) had deterioration of renal function or loss of renal size that led to operation. One patient required removal of a previously reconstructible kidney. Of the 17 patients with deterioration, 15 had acceptable blood pressure (BP) control during the period of nonoperative observation. Progressive deterioration of renal function in nonoperatively treated patients with atherosclerotic renal artery stenosis and RVH is common, and occurs even in the presence of BP control with drugs.     

Interpretation time of serial chest CT examinations with stacked-metaphor workstation versus film alternator

PURPOSE: Interpretation time of serial staging chest CT cases, which each contained current and previous examinations, with a simple prototype workstation called filmstack was experimentally compared with interpretation time with a film alternator. MATERIALS AND METHODS: The filmstack displayed a "stack" of sections for each examination; user controls allowed rapid selection of preset attenuation windows and both synchronized and unsynchronized scrolling. Eight radiologists were timed as they used the filmstack and the film alternator to interpret four ergonomically complex serial CT cases. RESULTS: All reports dictated on the basis of findings with filmstack and film were of acceptable clinical accuracy. The time to examine a case with filmstack was significantly faster than the time with film, including the time to load and unload the alternator (99% confidence [P = .01]). There was no statistically significant difference in interpretation time between filmstack and prehung film. CONCLUSION: Use of a low-cost stacked CT workstation with a single 1,024 x 1,024 monitor is an effective means of interpreting cases that require comparison of multiple CT examinations.     

Aspiration pneumonia following surgically placed feeding tubes

BACKGROUND: The enteral route is preferred in surgical patients requiring nutritional support; however, controversy surrounds the choice of location of feeding tube placement. Although jejunostomy has been commonly accepted as superior to gastrostomy for long-term nutritional support because of an assumed lower risk of aspiration pneumonia, recent studies suggest that reevaluation of common practices of surgical tube placement is warranted. PATIENTS AND METHODS: We conducted a retrospective chart review of gastrostomy and jejunostomy procedures from 1986 to 1993. Demographic information and complications related to the procedure were reviewed. Aspiration pneumonia was defined as respiratory symptoms, leukocytosis, and infiltrate on chest radiograph. RESULTS: Sixty-nine gastrostomies and 86 jejunostomies were performed during the study period. Six patients were diagnosed with aspiration pneumonia; 2 cases of which occurred with jejunostomy and 4 cases occurred with gastrostomy (P = not significant). CONCLUSIONS: There was no difference in rates of pulmonary aspiration or other complications between gastrostomy and jejunostomy. We suggest that when a surgically placed feeding tube is required, the determination of appropriate procedure be based on clinical factors such as the technical difficulty of the operation or long-term feeding goals.     

Cementless acetabular components: optimums and outcomes

The first known case of an intravascular catheter-related primary cutaneous mucormycosis in a heart transplant patient is reported. The patient had corticosteroid-induced hyperglycemia and experienced an acute tissue rejection episode. A necrotic lesion appeared around the insertion site of a peripheral venous catheter. A biopsy revealed typical mucorales hyphae. The lesion continued to spread during the following 24 hours and necessitated amputation of the forearm. The organism was identified as a Mucor species.     

Solution structure of a brodimoprim analogue in its complex with Lactobacillus casei dihydrofolate reductase

Two-dimensional (2D) double-quantum-filtered correlation spectroscopy (DQF-COSY), total correlation spectroscopy (TOCSY), nuclear Overhauser effect spectroscopy (NOESY), and rotating-frame NOESY (ROESY) spectra were used to assign essentially all the protons in a 1:1 complex of Lactobacillus casei dihydrofolate reductase formed with an analogue of the antibacterial drug brodimoprim [2,4-diamino-5-(3',5'-dimethoxy-4'-bromobenzyl)pyrimidine]. The analogue has a 4,6-dicarboxylic acid side chain substituted on the 3'-O position designed to interact with the Arg 57 and His 28 residues in L. casei dihydrofolate reductase; it binds a factor of 10(3) more tightly to the enzyme than does the parent compound. Thirty-eight intermolecular and 11 intramolecular NOEs were measured involving the bound brodimoprim-4,6-dicarboxylic acid analogue. These provided the distance constraints used in conjunction with an energy minimization and simulated annealing protocol (using Discover from Biosym Ltd.) to dock the brodimoprim analogue into dihydrofolate reductase. In calculations where side chains and backbone fragments for binding-site residues were allowed flexibility, 90% of the 40 calculated structures had reasonable covalent geometry and none of them had NOE distance violations of greater than 0.36 A. The conformations of the aromatic rings in the bound ligand were well-defined in all the structures, with torsion angles tau 1 = -153 degrees +/- 4 degrees (C4-C5-C7-C1') and tau 2 = 53 degrees +/- 4 degrees (C5-C7-C1'-C2'): the aromatic rings of the ligand occupied essentially the same space in all the calculated structures (root mean square deviation value 1.83 A). Inclusion of the electrostatic interactions into the energy minimizations indicated that structures in which the 4,6-dicarboxylate group of the ligand interacts with the side chains of Arg 57 and His 28 are of low energy. Significant differences in side-chain and backbone conformations were detected between binding-site residues in the enzyme complexes with the brodimorpim analogue and methotrexate.     

The effects of D-23129, a new experimental anticonvulsant drug, on neurotransmitter amino acids in the rat hippocampus in vitro

Recent literature continues to promote the early use of disease-modifying antirheumatic drugs (DMARDs), especially the less toxic agents such as hydroxychloroquine. Reports of combination DMARD treatments have been disappointing, and careful attention must be paid to clinical trial design if the efficacy of combination therapies is to be established. Methotrexate retains its prominent role, and its mechanism of action has been the subject of many reports; its toxicity remains the most common reason for treatment termination. Guidelines for monitoring hepatic toxicity of methotrexate have been published and may help reduce the need for invasive biopsy procedures. Significant risk factors for methotrexate pulmonary toxicity remain difficult to identify. Large placebo-controlled studies of both sulfasalazine and hydroxychloroquine have been reported and have demonstrated the efficacy of these agents in the treatment of early rheumatoid arthritis. Awareness of drug-toxicity profiles is important for physicians who prescribe these agents.