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C Graves

Publications and source records attributed to C Graves.

12 recordsLinked to original sources

Pheochromocytoma associated with prior carotid body tumors (chemodectomas). Detection with I-131 MIBG.

Chemodectomas (carotid body tumors) were surgically removed on two occasions, first 10 years and then 3 months prior to detection with I-131 MIBG of an adrenal pheochromocytoma in a 32-year-old man with a family history of chemodectoma. Recent reports suggest patients with multiple and/or familial instances of chemodectoma frequently have associated catecholamine-secreting tumors detectable with I-131 or I-123 MIBG. This case documents the above association and suggests that any patient with proven carotid body tumor(s) be screened for catecholamine-secreting tumors via urinary/plasma catecholamine determinations.

3-Iodobenzylguanidine

Promoting bicycle helmets: a new focus for injury prevention.

Bicycle accidents cause many serious injuries and deaths in the United States, often as a result of head injury in riders not wearing helmets. Helmets reduce the incidence of head injury, and an aggressive safety education campaign has been shown to increase the number of children wearing helmets while riding. Such a campaign has been initiated in the Central Indiana area. The campaign is designed to educate families and to promote bicycle helmet use among children and their parents. Suggestions are given on how physicians can help educate, distribute information and encourage bicycle helmet use through their contact with families. A resource list is included so these materials can be easily obtained. Ultimately, we hope such a program will increase helmet use and consequently reduce morbidity and mortality from head injury in Indiana's children.

Bicycling

Root surface caries subsequent to gingivectomy in rats inoculated with Streptococcus sobrinus (mutans) and Actinomyces viscosus.

We studied the effect of oral infection with cariogenic micro-organisms on alveolar bone loss and root surface caries subsequent to gingivectomy in rats. Thirty-six rats were fed diet MIT 200 (67% sucrose); one-half, the controls, had antibiotics added to the diet. At ages 18, 19, and 21 days, the experimental group was orally infected with streptomycin-resistant Streptococcus sobrinus (mutans) 6715 and Actinomyces viscosus M-100. At age 30 days, all animals were subjected to a gingivectomy on maxillary and mandibular left quadrants. The experimental group was re-inoculated at age 36 days. Animals were killed seven weeks after surgery. Jaws were stained, and planimetric measurements of exposed root surface area and caries on lingual/palatal surfaces of 1st and 2nd molars were made from video images with a computer/digitizer. Compared with the non-operated contralateral quadrants, gingivectomy significantly increased exposed root surface area in the maxilla and in the mandible in both the control and experimental groups. Oral inoculation significantly increased exposed root surface in mandibular (but not maxillary) quadrants which had received a gingivectomy, but had no effect on non-gingivectomized quadrants. There was no caries in the control group, whereas ten rats in the experimental group had root surface caries lesions, all in quadrants which had received a gingivectomy. This rat model should prove useful in further studies of root surface caries.

Actinomyces

Respiratory phase locking during mechanical ventilation in anesthetized human subjects.

The coupling patterns between the rhythm of a mechanical ventilator and the rhythm of spontaneous breathing were studied in enflurane-anesthetized adult human subjects. The spontaneous breathing pattern was altered in response to different frequencies and amplitudes of forced lung inflations. A 1:1 phase locking (the frequency of the mechanical ventilator is matched by the frequency of spontaneous breathing with a fixed phase between the 2 rhythms) was observed in a range of up to +/- 40% of some of the subject's spontaneous breathing frequencies. During 1:1 phase locking, there were marked changes in the expiratory duration as measured from the electromyogram of the diaphragm. The phase relationship between onset of inflation and onset of inspiration depended on the frequency and amplitude of mechanical inflation. At ventilator settings that did not give 1:1 phase locking, other simple phase-locked patterns, such as 1:2 and 2:1, or irregular non-phase-locked patterns were observed. Reflexes arising from lung inflation, which may underlie the entrainment, are discussed in the context of these results.

Adolescent

Mitral valve prolapse in patients with coronary artery disease. Echocardiographic-angiographic correlation.

Echocardiography was performed in 25 consecutive patients with angina pectoris and angiographically demonstrable coronary artery disease. Left ventricular echograms detected late or pansystolic mitral valve bowing suggesting of mitral valve proplapse in 6/25 (24%). Left ventricular angiography showed prolapse of the posterior mitral leaflet in 15/25 (60%), including 5 detected by echocardiography. Significant triple vessel coronary disease was present in 11 of 15 patients with prolapsed mitralvalve. In each of the latter a greater than 90 per cent obstructive lesion was noted in at least one coronary artery: right coronary artery, 9 subjects (82%); left circumflex coronary artery, 5 patients (33%); and left anterior descending coronary artery, 4 patients (27%). Of 15 subjects with angiographic evidence of mitral valve prolapse, 13 had left ventricular asynergy-inferior or inferoposterior in 8 subjects (62%) and anterior or anteroapical in 5 subjects (38%). Eleven subjects had vectorcardiographic evidence of transmural myocardial infarction-inferior or inferoposterior in 9 (82%) and anteroseptal in 2 (18%). A single subject with mitral valve prolapse had mild mitral regurgitation. It is concluded that: (1) coexisting prolapse of the posterior mitral valve leaflet and coronary artery disease is usually associated with triple vessel obstructive lesions, (2) severe right coronary disease, inferior left ventricular wall asynergy, and inferior myocardial infarction are important angiographic and vectorcardiographic correlates, and (3) echocardiography will detect such mitral valve prolapse in only one-third of affected cases.

Adult

Effects of coronary artery bypass surgery on hemodynamic parameters and derived indices of myocardial function.

Pre- and postoperative hemodynamic indices were compared in 116 patients subjected to aorto-coronary bypass after an average interval of 128 days. The patients were separated into three different groups according to graft status: Group 1 (n = 77), all grafts patent; Group 2 (n = 27), one occluded graft out of two or three implanted; Group 3 (n = 12), all grafts occluded. There were no significant major changes of values so obtained in the three groups. Those subjects with initially depressed cardiac indices or elevated left ventricular end-diastolic pressures manifested a significant trend toward improvement when at least one bypass graft was patent. A reduction of cardiac index was noted in patients with occluded left anterior descending coronary grafts only in association with closure of other grafts. Deterioration of cardiac index or left ventricular end-diastolic pressure into the abnormal range was unusual in the study group, even when all grafts were occluded. It is concluded that data relating to the influence of aorto-coronary bypass on standard indices of left ventricular function can be properly interpreted only when certain subsets of patients are studied.

Angina Pectoris

Correlation of electrocardiogram and vectorcardiogram with coronary occlusion and myocardial contraction abnormality.

Electrocardiograms and Frank vectorcardiograms were recorded in 156 consecutive patients with total occlusion of at least one coronary artery (on arteriography) and associated left ventricular contraction abnormality (on ventriculography). The angiograms and cardiograms were independently reviewed. In the presence of single vessel occlusion, appropriate vectorcardiographic diagnosis of myocardial infarction was determined in 118 of 156 cases (76 percent) compared with a lower electrocardiographic detection rate in 77 of 156 cases (49 percent). Findings diagnostic of two coexisting infarctions were observed in 71 percent of vectorcardiograms and 37 percent of electrocardiograms in 51 patients with double vessel occlusion and two areas of left ventricular dyskinesia. The vectorcardiographic detection rate was similarly superior to the electrocardiographic rate in the presence of subtotal coronary occlusion and myocardial asynergy in single (73 percent versus 53 percent) and double (53 percent versus 28 percent) vessel disease. The incidence rate of false positive diagnoses was 3 percent for electrocardiography and 4 percent for vectorcardiography. It is concluded that the vectorcardiogram is superior to the electrocardiogram in the diagnosis of obstructive coronary artery disease and left ventricular contraction abnormality.

Adult