PubMed Health⌕ Search

Biomedical subjects

T Flanagan

Publications and source records attributed to T Flanagan.

17 recordsLinked to original sources

The cost of teaching residents outpatient obstetrics and gynecology in a university medical center.

OBJECTIVE: To quantify the cost of teaching residents ambulatory obstetrics and gynecology, expressed as the difference in revenue generated between a faculty physician practicing as a private practitioner and a faculty physician serving as a resident supervisor. METHOD: Outpatient revenue generated by faculty generalists and residents was analyzed. The net gain in revenue was calculated per half-day session for faculty and residents by subtracting contractual allowances and expenses from gross patient charges. Net revenue gain per half-day clinical session per year for a faculty member practicing as a private practitioner was compared with that of a faculty member functioning as a supervisor. The net gain for the faculty supervisor was based on the revenue generated by the residents supervised. RESULTS: The faculty member serving as a private practitioner generated a net gain per session per year of $23,947. The faculty member acting as supervisor for two residents per session generated a net gain or loss per session per year of -$9678, -$972, and $15,542 for first-, second-, and third-year residents, respectively. The cost of teaching, expressed as the difference in the net gain of a faculty member as private practitioner and the net gain of a faculty member as supervisor, for first-, second-, and third-year residents was $33,625, $24,919, and $8405, respectively, per session per year. CONCLUSION: This analysis shows that first-year residents are an expense to the practice site, second-year residents are close to breaking even, and third-year residents begin to generate a net gain.

Ambulatory Care↗

Nucleotide and deduced amino acid sequence of bovine adrenal medulla chromogranin B (secretogranin I).

1. A novel 1745-dalton pyroglutamyl peptide (BAM-1745)6 was recently isolated and characterized from bovine adrenal medulla chromaffin granules. Its amino acid sequence was found to be 93% identical to residues 580-593 of human chromogranin B (secretogranin I). 2. Based on this sequence a degenerate oligonucleotide probe was synthesized and used to identify a 2.4-kb bovine adrenal medulla chromogranin B cDNA. 3. The deduced polypeptide is 647 amino acids long and begins with a putative signal sequence of 20 residues as in the human, rat, and mouse proteins. Also conserved in the bovine protein is a tyrosine residue which may be sulfated, two N-terminal cysteines, and many paired basic amino acids which may serve as sites of posttranslational processing. The peptide BAM-1745 is flanked by paired basic amino acids and therefore is most likely a product of posttranslational processing. Bovine chromogranin B is 67, 58, and 58% identical to the human, rat, and mouse chromogranin B proteins, respectively. 4. The carboxyl terminus of bovine chromogranin B, including BAM-1745, was found to be the most conserved region of the polypeptide and may identify it as an important functional domain.

Adrenal Medulla↗

Reducing postischemic paraplegia using conjugated superoxide dismutase.

Paraplegia after thoracic aortic aneurysm repair has an incidence of 2.2% to 24%. Oxygen-derived free radicals after reperfusion of an ischemic spinal cord may be partly responsible for neuronal destruction. We studied the effects of polyethylene glycol-conjugated superoxide dismutase (PEG-SOD), a free radical scavenger, as a way of increasing spinal cord tolerance to ischemia. Thirty rabbits underwent 40 minutes of aortic occlusion (a known model of paraplegia). Ten of these animals received 25,000 U/kg of PEG-SOD 24 hours before aortic occlusion and two additional doses of 10,000 U/kg, one before and one subsequent to spinal ischemia. Ten animals received superoxide dismutase in the same dosages as those receiving PEG-SOD. Ten control animals received placebo. All animals were studied for 96 hours, at which time a final neurological examination was performed and the results were recorded. Of the 10 animals treated with PEG-SOD, 2 were completely paralyzed whereas 8 had less (7) or no (1) neurological impairment. Eight of the 10 control animals and 9 of the 10 animals receiving superoxide dismutase were completely paralyzed. None of the control animals or animals receiving superoxide dismutase had a normal neurological examination (p less than or equal to 0.05). Treatment with PEG-SOD before and during occlusion increased the rabbit spinal cord tolerance to a 40-minute ischemic insult. Scavenging free radicals may lessen experimental spinal cord injury.

Animals↗

The risk of axillofemoral bypass grafting for acute vascular occlusion.

The hypothesis of the present study is that axillofemoral bypass grafting for acute vascular occlusion has results significantly inferior to an elective procedure. We reviewed 53 patients undergoing primary axillofemoral bypass grafting at the University of Virginia from 1984 to 1989. We found that patients who were admitted with acute vascular occlusion had a higher incidence of perioperative complications (63% vs 26%, p = 0.001), perioperative mortality (26% vs 3%, p less than 0.05), lower graft patency at 1 year (60% vs 90%, p less than 0.05), lower rate of freedom from reoperation in first year (50% vs 82%, p less than 0.01), and lower rates of limb salvage (76% vs 94%, p less than 0.05) than patients undergoing axillofemoral bypass grafting for chronic symptoms or conditions. These two groups did not differ in any of the other risk factors or perioperative characteristics examined. We conclude axillofemoral bypass grafting performed for indications other than acute vascular occlusion is associated with acceptable morbidity, mortality, graft patency, and limb salvage rates.

Acute Disease↗

A novel 1745-dalton pyroglutamyl peptide derived from chromogranin B is in the bovine adrenomedullary chromaffin vesicle.

1. Following the recent demonstration of a glutaminyl cyclase activity localized in adrenomedullary chromaffin vesicles, an assay was developed to isolate and characterize posttranslationally modified peptides from this tissue which contain pyroglutamate. This assay consisted of spectrometric identification of peptides before and after enzymatic removal of pyroglutamyl residues. 2. Using this procedure, a pyroglutamyl peptide (BAM-1745) was isolated and sequenced and was shown to be a significant component of adrenomedullary secretory vesicles. 3. A computer search through the Swiss-Prot protein sequence database revealed a 93% identity of BAM-1745 and a fragment of human chromogranin B (Gln580-Tyr593).

Acyltransferases↗

The effects of talc pleurodesis on growing swine.

Talc pleurodesis is an effective means of preventing recurrent pneumothorax. We have successfully applied talc pleurodesis with thoracoscopy in children with cystic fibrosis presenting with pneumothorax. However, little is known about the effects of talc pleurodesis on lung compliance in growing children. Therefore, six young pigs (10 weeks old, weighing 15 +/- 1 kg) were prepared for study. In each pig, one hemithorax underwent thoracoscopy and talc pleurodesis (TALC). The other hemithorax underwent either thoracoscopy alone or no procedure (CONTROL). Dynamic and static respiratory mechanics were studied 5 and 10 weeks later. Air flow and airway pressure were measured to calculate dynamic transpulmonary and transrespiratory compliance, and static transpulmonary compliance. At 5 weeks, dynamic transpulmonary and transrespiratory compliance were less in the TALC lungs when compared with CONTROL lungs. At 10 weeks, the differences in dynamic transpulmonary and transrespiratory compliance between the TALC and CONTROL lungs had resolved. Static compliance was lower in the TALC lungs than in the CONTROL lungs at both 5 and 10 weeks, but this was significant only at 10 weeks. There was an improvement in static compliance in the TALC lungs between 5 and 10 weeks, but this only approached significance. At autopsy, there were marked adhesions and pleural thickening in the talc lungs. Histological examination demonstrated no differences in lung parenchyma between the TALC lungs and the CONTROL lungs. Talc pleurodesis causes a temporary impairment in dynamic transpulmonary and transrespiratory compliance that resolves with time and growth. Static compliance is more persistently compromised, but a trend toward improvement with time and growth exists.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Probing of the canine mammary artery damages endothelium and impairs vasodilation resulting from prostacyclin and endothelium-derived relaxing factor.

It is routine practice for many cardiac surgeons to probe internal mammary arteries to dilate them before their use. The effects of such probing on endothelium integrity, prostacyclin production, and vasodilation resulting from endothelium-derived relaxing factor and from prostacyclin were investigated in vessels isolated from mongrel dogs. Dose-dependent relaxation responses of isolated segments of probed and unprobed mammary arteries to the endothelium-dependent vasodilators methacholine, calcium ionophore (A23187), and melittin were determined in both the presence and absence of indomethacin. Prostacyclin production by probed versus unprobed vascular segments was determined under basal and A23187-stimulated conditions by radioimmunoassay for 6-keto-prostaglandin F1 alpha, and endothelial integrity was determined by scanning electron microscopy. Scanning electron micrographs of segments revealed marked endothelial cell disruption in probed versus unprobed vessels. The dose-dependent relaxation responses to all drugs studied were significantly impaired (p less than 0.05) in probed versus unprobed vessels in both the presence and absence of indomethacin. In addition, prostacyclin release as measured by production of 6-keto-prostaglandin F1 alpha was significantly (p less than 0.05) impaired in probed versus unprobed vessels under both basal and A23187-stimulated conditions. These results imply that routine probing of the internal mammary artery may damage endothelium, impair prostacyclin production, and impair endothelium-dependent vasodilation resulting from both prostacyclin and endothelium-derived relaxing factor.

Animals↗

Probing structural homologies in cell-specific glycoproteins in the leech CNS.

Three monoclonal antibodies (mAbs) raised against the leech CNS recognize surface antigens on small sets and subsets of neurons or on glial cells. On immunoblots, they all recognize proteins of 130 kDa molecular weight. In addition, they each bind up to several different lower molecular weight forms. The 130 kDa polypeptides recognized by these mAbs are not major proteins on Coomassie blue-stained gels. They behave as glycoproteins on lentil lectin columns but are not major Concanavalin A-binding molecules. These molecules therefore represent a group of lower abundance, cell-type-specific antigens. Structural relationships between these antigens were explored using immunoprecipitation. The glial cell antigen was immunopurified, however, a fraction of the neuronal antigens co-precipitate. The co-precipitation of neuronal antigens raises the possibility that different neuronal antigenic determinants are carried on the same protein molecule. Such a protein may be modified to carry either one or both neuronal determinants, and could serve as a tag to physiologically delineate subsets of neurons nested within larger neuronal sets.

Animals↗

Antibody staining reveals novel aspects of segmentation within the leech central nervous system.

The leech is a segmented annelid with a well characterized central nervous system. In this report, we use antibodies to map the distribution of neurons confined to selected segmental ganglia in the mud leech Haemopis marmorata. The distribution of these neurons suggest 3 novel aspects of segmentation in the leech nervous system: (1) neurons are assigned to even-numbered ganglia through a mechanism which effectively counts through the leech segmental body plan by units of 2, (2) neurons are assigned to ganglia 7 and 14 through a mechanism which effectively counts in units of 7 and (3) neurons are assigned to the 2nd and 4 fused head ganglia and to the 2nd of 21 unfused midbody ganglia through a mechanism which effectively counts units from the origin of these 2 ganglionic series. These 3 hypothetical counting mechanisms divide the central nervous system (CNS) into supersegmental units. Neurons used to define these supersegmental units have been injected with tracer and identified as interganglionic interneurons. Competitive interactions among embryonic precursors of these neurons may directly eliminate their homologs from intervening ganglia, and thus sculpture supersegmental patterns into the mature nervous system.

Animals↗

Complement-fixing antiperipheral nerve myelin antibodies in patients with inflammatory polyneuritis and with polyneuropathy and paraproteinemia.

Serum from patients with peripheral neuropathies was tested for antiperipheral nerve myelin antibodies by complement fixation. Antibody activity was detected in 5 of 20 patients with acute or chronic remitting polyneuritis and in 4 of 20 patients with polyneuropathy and paraproteinemia but not in patients with other types of neuropathy, neurologic disease, or immunologic disease. In three patients with IgM paraproteinemia, the complement-fixing activity resided in the IgM fraction; in one patient with chronic inflammatory polyneuritis, antibody activity resided in the IgG fraction. In the inflammatory polyneuropathies, antibody titers did not always correlate with disease activity. Sera from patients with remitting polyneuropathies reacted with either human or rabbit peripheral nerve myelin, but sera from patients with paraproteinemia reacted only with human myelin.

Animals↗