Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0014118 (endocarditis)
 15,629 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was designed to evaluate the early phase events occurring in a stented pulmonary homograft valve implanted in the tricuspid position. A human pulmonary homograft was sterilized in antibiotic solution for 48 hours and cryopreserved in liquid nitrogen (-176 degrees C). Following thawing and trimming, the pulmonary valve was mounted on a Dacron cloth-covered Delrin stent and implanted into the tricuspid position in 3-month-old sheep, for a mean of 95 +/- 5 days. Seven animals were studied. Morphological assessment indicated good structural tissue preservation despite a decrease in viable fibroblasts noted in the distal part of the leaflets. The collagen fibers remained unchanged, and no tissue calcification was found. Viability of the mounted homograft was evaluated using an in vitro tissue culture method, and the viable cells underwent chromosomal analysis to identify whether they originated from the donor or host. Cells with 56 chromosomes, a number intrinsic to sheep cells, were cultured from the donor recipient junctional area. Hemodynamic and angiographic data, which were collected at the time of both implantation and explantation, revealed no functional deterioration of the implanted valve over 3 months. At the time of explantation, six of the seven valves were competent and no cusp retraction or thickening was noted. The seventh valve had deteriorated due to endocarditis. We conclude that stented cryopreserved pulmonary homografts may be useful as bioprostheses in the tricuspid position.
 ...
PMID:The cryopreserved stented pulmonary homograft valve in the tricuspid position. 160 72

Intravegetation host inflammatory cell function may play a role in the more salutary clinical outcomes in human right- vs. left-sided endocarditis. To study this in vivo, 90 rabbits with tricuspid Pseudomonas aeruginosa endocarditis received either no therapy (controls), nitrogen mustard (HN2) to induce combined granulocytopenia + monocytopenia, etoposide (VP-16-213) to induce selective monocytopenia, or dexamethasone. Intravegetation inflammatory cell influxes were scored on a semiquantitative histopathologic scale. In VP-16-213 and dexamethasone recipients and tricuspid endocarditis controls, gradual decreases in mean intravegetation bacterial densities were observed over a 13-day infection period; in contrast, HN2 treatment was associated with a significant increase in intravegetation bacterial densities by day 13 of infection (p less than 0.001 vs. other tricuspid endocarditis groups). Histopathologically, vegetations from untreated controls and dexamethasone recipients showed granulocyte influxes during infection, while HN2 treatment resulted in predominantly granulocyte depletion within infected tricuspid vegetations; VP-16-213 caused mononuclear cell depletion at this site. This study supports the concept that the granulocyte plays a critical role in modulating spontaneous endocardial clearances of bacteria in experimental tricuspid endocarditis.
 ...
PMID:Pathogenic effects of monocytopenia, granulocytopenia and dexamethasone on the course of experimental Pseudomonas aeruginosa endocarditis in rabbits. 250 46

A total of 1689 consecutive patients underwent isolated aortic valve replacement at the Cleveland Clinic Foundation from 1972 through 1986. There were 57 (3.4%) in-hospital deaths. Multivariate analysis identified advanced age (p = 0.0014), preoperative blood urea nitrogen level greater than 25 mg/100 ml (p = 0.008), New York Heart Association function class (p = 0.015), and preoperative atrial fibrillation (p = 0.04) as independent variables associated with increased in-hospital mortality and the use of cardioplegia for myocardial protection (p = 0.006) as a factor decreasing mortality. Follow-up documented survival rates of 85% and 66% and event-free survival rates of 71% and 43% at 5 and 10 postoperative years, respectively. Advanced age, moderate or severe impairment of left ventricular function, coronary artery disease, and preoperative blood urea nitrogen level greater than 25 mg/100 ml were associated with decreased late survival and event-free survival (all p less than 0.05). Patients with bioprostheses had better survival (p = 0.003) and event-free survival (p = 0.0007) rates than patients with mechanical valves. Patients with bioprostheses had superior results only if not receiving warfarin, and they experienced more reoperations and endocarditis; those with mechanical prostheses had more strokes, myocardial infarctions, bleeding complications, and thromboembolic events. Analysis of patients grouped according to age at operation showed that bioprostheses were associated with improved survival and event-free survival for patients 40 years older or older. Younger patients experienced more reoperations and episodes of endocarditis, and older patients more thromboembolic complications. We conclude that 10-year results after isolated aortic valve replacement are influenced by both patient-related and management-related variables, and the impact of these factors is different for patients of different ages.
 ...
PMID:Primary isolated aortic valve replacement. Early and late results. 270 60

From December 1969 to May 1975, 124 patients underwent aortic valve replacement with an allograft aortic valve sterilized by incubation in a low dose antibiotic solution and stored by refrigeration at 4 degrees C (4 degrees C stored valve group). From June 1975 to December 1987, 231 patients received an allograft aortic valve, sterilized by the same low dose antibiotic solution, but stored by cryopreservation in liquid nitrogen at -196 degrees C (cryopreserved valve group). The 4 degrees C stored valves were essentially nonviable, whereas the cryopreserved valves were viable at implantation. Of the 355 aortic valve replacements, associated procedures were performed in 127 patients. The 30-day mortality was 8.9% (confidence limits [C.L.] 6.2% ... 12.3%) (4 degrees C stored) and 4.8% (C.L. 3.3% ... 6.7%) (cryopreserved). Actuarial survival was similar in both groups, being 71% and 67% at 10 years in the 4 degrees C stored and cryopreserved valve groups, respectively (P = .18). The probability of a thromboembolic event was low, but appeared higher in the 4 degrees C stored valve group (actuarial freedom at 10 years, 90%) than the cryopreserved valve group (actuarial freedom at 10 years, 98%) (P = .01) probably related to associated mitral valve surgery. The actuarial freedom from allograft valve endocarditis at 10 years was 94% and 95% for the 4 degrees C stored and cryopreserved valve groups, respectively (P = .23). Reoperation was undertaken in 34 patients in the 4 degrees C stored group and 12 patients in the cryopreserved valve group for leaflet degeneration, endocarditis, or technical reasons.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Long-term results of the viable cryopreserved allograft aortic valve: continuing evidence for superior valve durability. 298 29

We examined the long-term clinical function and fate of allograft aortic valves, preserved by two differing methods, for aortic valve replacement: (1) fresh allografts stored at 4 degrees C refrigeration (group I) and (2) viable allografts cryopreserved in liquid nitrogen at -196 degrees C (group II). A total of 316 aortic valve replacement operations were performed, 124 in group I (December 1969 to May 1975) and 192 in group II (June 1975 to December 1986). Concomitant surgical procedures (eg, coronary artery bypass grafting and mitral valve replacement) were necessary in 120 operations. The overall immediate 30 day mortality was 6.0% (confident limits 4.6% to 7.7%), and the survival rates were 83% at 4 years and 60% at 15 years. Endocarditis and technical factors concerning reoperation showed no difference between the two groups according to parametric estimates and hazard function analyses. However, there was a marked difference in reoperation for valve degeneration: 23 patients in group I and 0 patients in group II. The freedom from reoperation for valve degeneration at 10 years was 89% for group I and 100% for group II, and at 15 years it was 59% for group I. The hazard function for group I reflected the late rising risk of degeneration. The freedom from thromboembolism of both groups (aortic valve replacement with or without bypass grafting) was 97% at 10 years and 96% at 15 years. Group II explanted valves (operation for technical malalignment reasons) has consistently shown evidence of persisting viability on tissue culture, on metabolic studies, and on histologic appearances. Chromosomal studies have shown the donor origin of these cells. The superior results with the cryopreserved valve is considered to be due to persisting viability, which appears to be the key to durability.
 ...
PMID:A comparison of aortic valve replacement with viable cryopreserved and fresh allograft valves, with a note on chromosomal studies. 368 51

A group of 12 children and 5 adults, all with diffuse non-Hodgkin's malignant lymphoma (NHML), received massive chemotherapy regimens. The stages of the disease were as follows: 7 patients were in second complete remission; 6 in a progressive phase of the disease; and 4 in first complete remission which occurred late in the course of the disease. All patients received BACT (BCNU+aracytine+cyclophosphamide+thioguanine) or TACC (idem with CCNU) at different dose levels: 6/17 received 10 Gy total-body irradiation (TBI) after BACT treatment; 16/17 received autologous bone marrow transplantation (ABMT) previously stored in liquid nitrogen to combat the medullary effects of chemotherapy. Direct therapy-related deaths occurred in 4/17 patients (1 Aspergillus endocarditis; 1 Moskowitz syndrome; 1 veno-occlusive disease of the liver; and 1 Escherichia coli pneumopathy) and 6/17 patients relapsed between days 25 and 70 of treatment. Seven out of these 17 patients are still alive NED 102-900 days (mean, 475 days) after the beginning of therapy without receiving maintenance treatment. Massive chemotherapy could thus be the best treatment for NHML in relapse, but the high percentage of early therapy-related deaths is a strong limiting factor for patients before relapse.
 ...
PMID:Massive BACT chemotherapy with autologous bone marrow transplantation in 17 cases of non-Hodgkin's malignant lymphoma with a very bad prognosis. 635 3

The role of granulocytes and monocytes during the induction and course of Escherichia coli endocarditis was investigated in rabbits by selectively depleting monocytes from the circulation with the drug VP16-213 and granulocytes and monocytes with nitrogen mustard. For induction, the number of E. coli needed to infect the vegetations in 50% of the rabbits was significantly lower in rabbits with combined granulocytopenia and monocytopenia than in those with selective monocytopenia or in control rabbits, whereas the number of E. coli needed to infect 50% of the rabbits did not differ between the latter two. During the course of the endocarditis in endocardial vegetations, the numbers of CFU per gram of vegetation were significantly higher in the rabbits with combined granulocytopenia and monocytopenia than in the monocytopenic and control rabbits but did not differ between the latter two. The numbers of granulocytes in the circulation and the numbers of CFU per gram of vegetation showed a significant negative correlation that was not measurably influenced by the duration of the disease but was dependent on the number of E. coli injected for the induction of endocarditis. Granulocytes were found to be most effective at the lowest numbers of bacteria injected. In the circulation, too, the numbers of CFU per milliliter were significantly higher in rabbits with combined granulocytopenia and monocytopenia than in those with selective monocytopenia and control rabbits, and there was a significant negative correlation between the numbers of granulocytes and CFU per milliliter of blood. From these findings we conclude that granulocytes play a protective role during the induction and course of E. coli endocarditis in rabbits, whereas no role is demonstrable for monocytes.
 ...
PMID:Role of granulocytes and monocytes in experimental Escherichia coli endocarditis. 636 88

The role of granulocytes and monocytes during the induction and course of Staphylococcus epidermidis endocarditis was investigated by the selective depletion of monocytes with the drug VP16-213 and of both granulocytes and monocytes with nitrogen mustard. The induction of endocarditis was influenced only by the depletion of monocytes: the 50% infective dose differed significantly, being 3.4 X 10(5) CFU in control rabbits and 3.4 X 10(4) CFU in the monocyte-depleted rabbits, whereas no significant differences were found between the latter and those depleted of both granulocytes and monocytes. Also, control rabbits injected with 10(6) or 10(7) CFU had a significantly higher incidence of sterile vegetations than did rabbits selectively depleted of granulocytes or monocytes. Compared with baseline values, mean monocyte numbers at the time of bacterial inoculation were significantly increased in control rabbits whose vegetations remained sterile, whereas this effect was not seen in rabbits whose vegetations became infected. The course of the endocarditis appeared to be significantly influenced by both granulocytes and monocytes. Comparison showed that a decrease of the same numbers of these cells per microliter of blood was accompanied for the monocytes by an approximately fourfold higher increase of the number of staphylococci in the vegetations. The correlation between the number of granulocytes and of monocytes on the one hand and the number of staphylococci in the vegetations on the other was not substantially influenced by the duration of the disease or the number of staphylococci injected to induce the endocarditis. The number injected proved to be significantly correlated with the number of staphylococci in the vegetations. In rabbits with numbers of CFU per gram of vegetation exceeding 10(7), blood cultures were usually positive. This finding applied rarely to control rabbits, but generally to drug-treated rabbits. In the latter animals a significant correlation between the number of staphylococci in the vegetations and in the circulation was found. We conclude that only monocytes have a measurable effect on the induction of Staphylococcus epidermidis endocarditis but during its course both granulocytes and monocytes keep the endocardial infection in check.
 ...
PMID:Role of granulocytes and monocytes in experimental Staphylococcus epidermidis endocarditis. 686 24

Cellular host defenses are considered to be ineffective in bacterial endocarditis; the microorganisms in infected vegetations are protected from phagocytic cells by dense layers of fibrin. To test this hypothesis, nitrogen mustard-induced agranulocytosis and leukopenia were produced in rabbits with right-sided streptococcal endocarditis. The spontaneous sterilization of tricuspid infection observed in the control animals was not present in the granulocytopenic, leukopenic animals. Since the bacterium Streptococcus intermedius is not sensitive to the complement-mediated bactericidal effect of serum and since the animals were not bacteremic during the time of agranulocytosis, an inhibitory effect of the drug on local cellular host defense mechanisms is postulated. We suggest that the spontaneous sterilization of infective endocarditis in the right side of the heart in rabbits is mediated by cellular host defenses.
 ...
PMID:Effect of nitrogen mustard on natural history of right-sided streptococcal endocarditis in rabbits: role for cellular host defenses. 705 24

We investigated the role of granulocytes during the induction and course of experimental Streptococcus sanguis endocarditis in rabbits by depleting blood granulocytes with nitrogen mustard. The induction of the endocarditis was not influenced by granulocytopenia: the 50% infectious dose was 5.4 X 10(4) colony-forming units in normal and granulocytopenic rabbits. However, granulocytopenia influenced the curse of the endocarditis, as shown by a significant increase in the number of colony-forming units per gram of vegetation (P less than 0.02) from 24 to 72 h after the injection of 10(5) colony-forming units of S. sanguis. This rise did not occur in the control rabbits. Furthermore, bacteremia was significantly higher in the granulocytopenic rabbits (P less than 0.05) during the first 48 h compared with the control rabbits. This was not because of altered clearance of the streptococcus inoculum or seeding of streptococci from extracardiac bacterial foci. We concluded that granulocytes have no measurable effect on the induction of S. sanguis endocarditis, but during the course of the endocarditis, granulocytes keep the endocardial infection in check.
 ...
PMID:Role of granulocytes in experimental Streptococcus sanguis endocarditis. 707 2


1 2 3 Next >>