PubMed Health⌕ Search

Biomedical subjects

J W Love

Publications and source records attributed to J W Love.

At least 19 recordsLinked to original sources
PubMed1992

Experimental evaluation of an autologous tissue heart valve.

The goal of the autologous tissue heart valve (ATHV) prosthesis project has been the development of a non-antigenic, non-calcifying bioprosthesis of greater durability than heterograft or homograft bioprostheses. It is made in the operating room, at a sterile work bench, during surgery for heart valve replacement. Autologous pericardium is used for valve construction after a five minute immersion in 0.6 per cent glutaraldehyde buffered to pH 7.4 with phosphate. The stent-mounted trileaflet prosthesis can be made in five minutes with a semi-automated method that uses two concentric mating stents that substitute clamping for sewing of the tissue. In vitro testing, to include pulse duplicator, accelerated wear tester, static testing for leakage and tensile strength testing, has been performed with ATHVs made with glutaraldehyde-tanned bovine and ovine pericardium. Transvalvular pressure gradients were measured at 3.3-7.3 mmHg at flow rates of 4-5 l/min. Six valves have been tested beyond 800,000,000 cycles with full opening and closing at differential closing pressures of 125 mmHg. One of the valves developed a 2mm leaflet tear after 26,000,000 cycles but the remaining five survived intact. No fractures were seen in the Dacron covered Delrin stents. Six ATHVs were implanted in juvenile sheep for five months. One animal died after five months of infective endocarditis secondary to an unrecognized deep wound infection and the other five were electively sacrificed at the same time interval. Four valves were fully competent at terminal elective cardiac catheterization and one showed minimal insufficiency attributed to a paravalvular leak. The leaflet tissue was free of generalized calcification in all instances. There was no evidence of leaflet tissue thickening or shrinkage. The mean calcium content at necropsy of the 15 leaflets from the five valves was 8.357 mg/g of tissue. There is experimental evidence that an ATHV made of pericardium treated briefly with glutaraldehyde may achieve the goal of a non-calcifying, more durable bioprosthesis.

Animals↗
PubMed1991

The effectiveness of a counterrotational-action power toothbrush on plaque control in orthodontic patients.

This study compared counterrotational-action power toothbrushing with manual toothbrushing in effectiveness on plaque control and gingival health in 20 randomly selected orthodontic patients at the University of Missouri-Kansas City. A blind two-group crossover design was used. Gingival and plaque scores were recorded, and a prophylaxis was given to bring the plaque score to zero. Ten subjects received counterrotational power brushes, and ten subjects received manual brushes. Instructions appropriate to each brushing method were given by a hygienist. At 30 and 60 days, plaque and gingival scores were recorded and a prophylaxis was given. At 60 days the subjects who were using power brushes were switched to manual brushes, and the subjects who were using manual brushes were switched to power brushes. At 30 and 60 days, plaque and gingival scores were recorded and a prophylaxis was given. Plaque and gingival scores were significantly less (p less than 0.01) after brushing 2 months with the counterrotational power brush than with the manual brush. This finding was irrespective of the sequence in which the brushes were used.

Adolescent↗
PubMed1991

The autogenous tissue heart valve: current status.

Residual antigenicity of xenograft tissue after glutaraldehyde tanning may be a factor that determines calcification and durability of bioprostheses. We have pursued the concept of a nonantigenic, noncalcifying, more durable bioprosthesis. We previously described a technique for rapid intraoperative fabrication of an autogenous tissue heart valve (ATHV). That technique has been modified to improve reliability and ease of learning. With the modified technique, a geometrically perfect trileaflet valve can be made in 5 minutes. Although any suitable tissue can be used, the pericardial ATHV is the subject of this report. Autogenous pericardium immersed for 5 minutes in glutaraldehyde has proven satisfactory for valve construction. In vitro testing in the pulse duplicator and accelerated life tester has shown that the stent assembly is capable of function beyond 800,000,000 cycles without failure. In vivo testing has been performed in the juvenile sheep model as described by the National Institutes of Health group. Five sheep were maintained for 5 months postimplant before sacrifice. Explanted valves showed no tissue thickening or shrinkage, problems seen with earlier valves made with untreated autogenous tissue, and the leaflets remained pliable, free of the degenerative changes usually seen in the sheep model.

Animals↗
PubMed1989

The effectiveness of a counter-rotary action powered toothbrush and conventional toothbrush on plaque removal and gingival bleeding. A short term study.

Initial investigations have demonstrated the effectiveness of a new contra-rotary powered electric toothbrush in removing plaque supragingivally, subgingivally, and interproximally following a single use. The purpose of this study was to evaluate the effectiveness of a counter-rotary toothbrush following 1) one time instruction, 2) reinstruction and 1 week practice; and 3) a third instruction and 3 weeks of practice and home use. Twenty-four patients were studied; 12 using the counter-rotary toothbrush and 12 using a conventional toothbrush. Using O'Leary and Turesky plaque indices, both brushes significantly reduced supragingival plaque from baseline at all intervals. The counter-rotary brush, however, was more efficient than the conventional brush at all intervals (P less than 0.01). Using a Surface Area Plaque Index, both brushes significantly reduced supragingival plaque from baseline at all intervals but there were no significant differences between brushes. A timed bleeding index showed significant reduction in gingival bleeding following 28 days of brushing with both brushes. Again, the counter-rotary toothbrush was superior to the conventional toothbrush (P less than 0.01).

Dental Plaque↗
PubMed1989

Effects of an air-powder abrasive system on plasma-sprayed titanium implant surfaces: an in vitro evaluation.

The purpose of this study was to conduct an in vitro evaluation of the effects of an air-powder abrasive system, commonly used in clinical dentistry for periodontal maintenance, on the surfaces of plasma-sprayed titanium dental implants. Twenty-eight plasma-coated titanium implant specimens were divided into a sterile water-treated control group and an air-powder-abrasive-treated test group. All specimens were subjected to three different in vitro testing conditions and post-treatment evaluations by scanning electron microscopy (SEM): (1) Topographical features of implant surfaces were studied before and after direct exposure to the abrasive; (2) biocompatibility of treated implant surfaces was evaluated and compared with those of control specimens via in vitro fibroblast attachment studies; and (3) the attachment of a common oral microbe to the implant surface and its subsequent removal by exposure to the air-powder abrasive were also evaluated. Results indicate that exposure of implant specimens to the air-powder abrasive for various periods resulted in only slight changes in surface topography, i.e., rounding of angles and edges of the plasma-spray coating and occasional surface pitting. Examination by SEM and a statistical comparison of the difference between the mean numbers of attached fibroblasts between control and test groups revealed no statistical significance. In both specimen groups, fibroblasts exhibited uniform attachment over the entire implant surface. A comparison of test and control groups demonstrated 100% removal of bacteria from the surfaces of test specimens exposed to the air-powder abrasive and approximately a 75% removal from control specimens exposed to sterile water.

Bacterial Adhesion↗
PubMed1986

Heyde's syndrome.

Explore the source record for details and available documents.

Aortic Valve Stenosis↗
PubMed1982

The syndrome of calcific aortic stenosis and gastrointestinal bleeding: resolution following aortic valve replacement.

A syndrome exists in elderly patients of gastrointestinal tract bleeding (GIB) associated with calcific aortic stenosis (CAS). The bleeding, which may be chronic and massive, has been attributed to tiny mucosal vascular lesions which usually occur in the right colon. Selective mesenteric angiography is the best way to demonstrate the lesions, which are not seen on barium examination and may not been seen endoscopically. Previously, the recommended treatment has been segmental bowel resection, usually right hemicolectomy. Three patients have been seen with this syndrome of CAS-GIB. All three patients had severe CAS and chronic GIB and two of them had had previous, unsuccessful, intestinal operations for their GIB. All three patients had aortic valve replacement and the GIB stopped in all three patients after valve replacement. Possible mechanisms are discussed. It is concluded that aortic valve replacement is the treatment of choice for the syndrome of CAS-GIB.

Aged↗
PubMed1981

Left ventricular pseudoaneurysm secondary to infection after coronary bypass surgery.

We present a case of left ventricular pseudoaneurysm following coronary bypass surgery. The cause was infection, dating from the bypass procedure 1 1/2 years before. Repair of pseudoaneurysm in a patient with a bypass is complicated by the presence of grafts which should be protected from injury. Details of successful management in this case are presented.

Coronary Artery Bypass↗
PubMed1980

Employment status after coronary bypass operations and some cost considerations.

The occupational consequences and expenses of the bypass operation have been investigated in 100 survivors of 102 consecutive operations for coronary artery bypass grafting. There was one late death 8 months after the operation, and four patients were lost to follow-up, providing a total of 95 patients for survey. Patients were divided into four groups: I, those working before and after the operation (43); II, those working before but not after the operation (18); III, those not working before the operation who returned to work after the operation (8); IV, those not working before or after the operation (26). The four groups were analyzed for age, type of employment, severity of disease, ventricular function, incidence of perioperative infarction, graft patency, postoperative treadmill performance, and exepnses incurred. Profiles of the four groups have emerged which may have predictive value. Group I patients tend to be under age 55, self-employed in higher skill occupations, and with significant left ventricular dysfunction. Group II patients tend to be over age 55, employed in lower skill occupations, but also without significant left ventricular function. Of the 34 patients unemployed for 6 months in 24 months before the operation, 24% (eight) returned to work after the operation. The typical total bill for diagnosis and treatment was $15,000, of which insurance paid $12,000 and the patient paid $3,000.

Age Factors↗
PubMed1980

Myocardial revascularization in patients with chronic renal failure.

Symptomatic coronary artery disease in patients with chronic renal failure can complicate their management in a dialysis program. Hypotension associated with hemodialysis and the anemia of chronic renal disease can produce anginal episodes refractory to medical management. Untreated coronary artery disease may be a contraindication to renal transplantation in an otherwise acceptable candidate. We have encountered three cases of coronary artery disease severe enough to necessitate coronary bypass in patients from our long-term hemodialysis program. All three patients had uncomplicated postoperative courses, none had perioperative infarction, and in all three patients postoperative angiography demonstrated patency of all grafts. One patient subsequently underwent successful renal transplantation; the other two patients have continued in hemodialyses since bypass. We believe our experience and the reported experience of others confirm the feasibility of coronary bypass grafting in patients with chronic renal failure.

Adult↗
PubMed1976

Bypass of the right and circumflex coronary arteries with the internal mammary artery.

Our experience with the internal mammary artery (IMA) for coronary bypass grafting in the past 3 years includes 323 grafts in 253 patients. After an initial group of IMA to left anterior descending (LAD) coronary artery grafts, we began using the IMA to bypass circumflex and small right coronary arteries (RCA). This report describes our experience with IMA bypass of coronary vessels other than the LAD. A total of 96 patients have had an IMA graft to the circumflex or RCA. Most of these patients had two or more bypasses. The mortality rate for this group has been 7 per cent, 7 of 96 patients. Postoperative angiography in 82 of 89 survivors has shown a patency rate of 98 per cent in 83 of 85 grafts studied. We conclude that the IMA is the vessel of choice for coronary artery bypass and that it can be used to bypass any of the main coronary arteries.

Adult↗