Search PubMed⌕ Search

Biomedical subjects

John Barrett

Publications and source records attributed to John Barrett.

39 records · Page 3Linked to original sources

Prospective evaluation of the sensitivity of physical examination in chest trauma.

BACKGROUND: Chest radiographs are routine for patients presenting with blunt and penetrating chest trauma. The accuracy of physical examination in the diagnosis of hemopneumothorax in these patients is unclear. A prospective study was performed to define the utility of routine portable chest radiographs in 676 trauma patients. METHODS: Over 19 months (January 2000-July 2001), 676 patients who presented with penetrating or blunt chest trauma were interviewed and examined for signs and symptoms of hemopneumothorax. The incidence of chest pain or tenderness and tachypnea was noted and both lung fields were auscultated. A portable chest radiograph was then performed on all the patients. RESULTS: All the patients were hemodynamically stable. Five hundred twenty-three patients sustained blunt trauma, with seven hemopneumothoraces (1.3%). The negative predictive values of auscultation, pain or tenderness, and tachypnea were 99& to 100%. One hundred fifty-three patients sustained penetrating chest trauma. Of these injuries, 68 were gunshot wounds and 85 were stab wounds. Twenty-four (16%) of these patients had hemopneumothoraces. The sensitivities of auscultation, pain or tenderness, and tachypnea were 50%, 25%, and 32%, respectively. The negative predictive values of these tests were < 91%. CONCLUSION: Blunt chest trauma patients who are hemodynamically stable with a normal physical examination do not require a routine chest radiograph. In contrast, all victims of penetrating trauma require chest radiographs because many will have hemopneumothorax in the absence of clinical findings.

Adolescent↗

Structure-activity relationships of 111In- and 99mTc-labeled quinolin-4-one peptidomimetics as ligands for the vitronectin receptor: potential tumor imaging agents.

The integrin receptor alpha(v)beta(3) is overexpressed on the endothelial cells of growing tumors and on some tumor cells themselves. Radiolabeled alpha(v)beta(3) antagonists have demonstrated potential application as tumor imaging agents and as radiotherapeutic agents. This report describes the total synthesis of eight new HYNIC and DOTA conjugates of receptor alpha(v)beta(3) antagonists belonging to the quinolin-4-one class of peptidomimetics, and their radiolabeling with (99m)Tc (for HYNIC) and (111)In (for DOTA). Tethering of the radionuclide-chelator complexes was achieved at two different sites on the quinolin-4-one molecule. All such derivatives maintained high affinity for receptor alpha(v)beta(3) and high selectivity versus receptors alpha(IIb)beta(3), alpha(v)beta(5), alpha(5)beta(1). Biodistribution of the radiolabeled compounds was evaluated in the c-neu Oncomouse mammary adenocarcinoma model. DOTA conjugate (111)In-TA138 presented the best biodistribution profile. Tumor uptake at 2 h postinjection was 9.39% of injected dose/g of tissue (%ID/g). Activity levels in selected organs was as follows: blood, 0.54% ID/g; liver, 1.94% ID/g; kidney, 2.33% ID/g; lung, 2.74% ID/g; bone, 1.56% ID/g. A complete biodistribution analysis of (111)In-TA138 and the other radiolabeled compounds of this study are presented and discussed. A scintigraphic imaging study with (111)In-TA138 showed a clear delineation of the tumors and rapid clearance of activity from nontarget tissues.

Adenocarcinoma↗