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D Do

Publications and source records attributed to D Do.

At least 37 records · Page 2Linked to original sources
PubMed1997

A consensus approach to diagnosing coronary artery disease based on clinical and exercise test data.

OBJECTIVE: To demonstrate that a consensus approach for combining prediction equations based on clinical and exercise test variables derived from different populations can stratify patients referred for possible coronary artery disease (CAD) into low-, intermediate-, and high-risk groups. DESIGN: Retrospective analysis of consecutive patients with complete data from exercise testing and coronary angiography referred for evaluation of possible CAD. After derivation of a logistic equation in our own training set of patients, this equation, along with two other equations developed independently by other investigators, was validated in a test set. The validation strategy for the consensus approach included the following: (1) calculation of probability scores for each patient using each logistic equation independently; (2) determination of probability thresholds in the training set to divide the patients into three groups-low risk (prevalence CAD <5%), intermediate risk (5 to 70%), and high risk (>70% prevalence of CAD); (3) using agreement among at least two of three of the prediction equations to generate "consensus" for each patient; and (4) application of the consensus approach thresholds to the test set of patients. SETTINGS: Two university-affiliated Veteran's Affairs medical centers. PATIENTS: We studied 718 consecutive men between 1985 and 1995 who had coronary angiography within 3 months of an exercise treadmill test for suspected CAD. The population was randomly divided into a training set of 429 patients and a test set of 289 patients. Patients with previous myocardial infarction or coronary artery bypass surgery, valvular heart disease, left bundle branch block, or any Q waves present on their resting ECG were excluded from the study. MEASUREMENTS: Recording of clinical and exercise test data along with visual interpretation of the ECG recordings on standardized forms and abstraction of visually interpreted angiographic data from clinical catheterization reports. RESULTS: We demonstrated that by using simple clinical and exercise test variables, we could improve on the standard use of ECG criteria during exercise testing for diagnosing CAD. Using the consensus approach divided the test set into populations with low, intermediate, and high risk for CAD. Since the patients in the intermediate group would be sent for further testing and would eventually be correctly classified, the sensitivity of the consensus approach is 94% and the specificity is 92%. The consensus approach controls for varying disease prevalence, missing data, inconsistency in variable definition, and varying angiographic criterion for stenosis severity. The percent of correct diagnoses increased from the 67% for standard exercise ECG analysis and from the 80% for multivariable predictive equations alone to >90% correct diagnoses for the consensus approach. CONCLUSIONS: The consensus approach has made population-specific logistic regression equations portable to other populations. Excellent diagnostic characteristics can be obtained using simple data and measurements. The consensus approach is best applied utilizing a programmable calculator or a computer program to simplify the process of calculating the probability of CAD using the three equations.

Coronary Angiography↗
PubMed1996

Human CD4+ and CD8+ T lymphocytes are both cytotoxic to Toxoplasma gondii-infected cells.

Studies to determine if Toxoplasma gondii-specific human T cells lyse parasite-infected cells have yielded conflicting results. Furthermore, attempts to obtain human cytotoxic CD8+ T lymphocytes have been difficult because of the lack of a reproducible system for their generation. By using paraformaldehyde-fixed, T. gondii-infected peripheral blood mononuclear cells as antigen-presenting cells, we developed a method whereby T. gondii-specific T-cell lines can be reproducibly generated. Six T. gondii-specific T-cell lines were generated from an individual chronically infected with T. gondii. Cytofluorometric analysis of these lines revealed > 99% CD3+, 85 to 95% CD3+ alpha beta T-cell-receptor-positive (TCR+), 5 to 9% CD3+ gamma delta TCR+, 50 to 70% CD4+, and 20 to 40% CD8+ cells when cells were examined during the first 3 weeks of stimulation and >99% CD3+, >99% CD3+ alpha beta TCR+, < 1% CD3+ gamma delta TCR+, 20 to 40% CD4+, and 60 to 80% CD8+ cells when cells were examined between 5 and 11 weeks. Both CD4+ and CD8+ T cells had remarkable cytotoxic activity against T. gondii-infected target cells (30 to 50% specific Cr release at an effector-to-target ratio of 30:1) but not against uninfected target cells ( < 10% at an effector-to-target ratio of 30:1). Cytotoxic activity by the whole T-cell lines was not T. gondii strain specific. Whole T-cell lines were cytotoxic for target cells infected with the C56 and ME49 strains and the RH strain (which was used to infect peripheral blood mononuclear cells). T. gondii-specific T-cell lines displayed the predominant expression of V beta 7 TCR. The CDR3 regions of the V beta 7 TCRs of these T-cell lines showed a striking degree of sequence identity (oligoclonality). T-cell lines obtained by the method reporter here can be used to characterize functional activity of T-lymphocyte subsets in humans infected with T. gondii.

Amino Acid Sequence↗
PubMed1996

[Hemoperitoneum caused by leiomyoma of the colon].

The authors report a case of colon leiomyoma revealed by spontaneous hemoperitoneum. This a rare case in which we do not have a gastrointestinal bleeding of the tumor with melena but an endoperitoneal bleeding with hemoperitoneum. Pathologic and clinical aspects of intestinal leiomyomas are discussed, most of them are found in the stomach and only 3% arise in the colon. In this case was also found an histopathological test of a carcinoid of the appendix.

Aged↗
PubMed1995

Preferential activation and expansion of human peripheral blood gamma delta T cells in response to Toxoplasma gondii in vitro and their cytokine production and cytotoxic activity against T. gondii-infected cells.

Studies were conducted to determine if gamma delta T cells participate in the immune response to Toxoplasma gondii. Preferential expansion of human gamma delta T cells occurred when peripheral blood T cells from either T. gondii-seronegative or seropositive individuals were incubated with autologous PBMC infected with the parasite. That gamma delta T cells proliferated after incubation with infected cells was confirmed using purified of gamma delta T cells. These T. gondii-induced gamma delta T cell responses did not require prior exposure to the parasite since T cells obtained from umbilical cord blood from seronegative newborns also exhibited preferential expansion of gamma delta T cells. Cytofluorometric analysis of T cells obtained from either umbilical cord blood or peripheral blood from adults revealed that V gamma 9+ and V delta 2+ gamma delta T cells responded to stimulation with infected cells. Preferential expansion of gamma delta T cells was not restricted by polymorphic determinants of MHC molecules. PBMC that had internalized killed parasites but not PBMC incubated with T. gondii lysate antigens also stimulated preferential expansion and activation of gamma delta T cells as assessed by expression of CD25 and HLA-DR molecules. V gamma 9+V delta 2+ gamma delta T cells were cytotoxic for T. gondii-infected cells in an MHC-unrestricted manner, and produced IFN-gamma, IL-2, TNF-alpha, but not IL-4 when incubated with cells infected with the parasite. These results suggest that rapid induction of a remarkable primary gamma delta T cell response may be important in the early protective immune response to T. gondii.

Animals↗
PubMed1994

A nomogram to predict exercise capacity from a specific activity questionnaire and clinical data.

Recent investigations suggested that clinical exercise testing can be optimized by individualizing the protocol, depending on the purpose of the test and the subject tested. This requires some knowledge of a patient's exercise capacity before beginning the test. The accuracy of a simple physical activity questionnaire and readily available clinical data in predicting subsequent treadmill performance was examined. A brief, self-administered questionnaire (VSAQ) was developed for veterans who were referred to exercise testing for clinical reasons. The VSAQ was designed to determine which specific daily activities were associated with symptoms of cardiovascular disease (fatigue, chest pain and shortness of breath). Two hundred twelve consecutive patients (mean age 62 +/- 8 years) referred for maximal exercise testing were studied. Clinical and demographic variables were added to VSAQ responses in a stepwise regression model to determine their ability to predict treadmill performance. Only metabolic equivalents by VSAQ, and age were significant predictors of treadmill performance; these 2 variables yielded R = 0.82 (SEE 1.43; p < 0.001), and explained 67% of the variance in exercise capacity. The regression equation reflecting the relation between age, VSAQ and exercise capacity was: achieved metabolic equivalents = 4.7 + 0.97 (VSAQ) - 0.06 (age). Using this equation, a nomogram was developed. Incorporating the VSAQ with the nomogram requires only a few minutes, and yields a reasonably accurate estimate of a patient's exercise capacity. Although the present equation is population-specific, a similar approach in different populations may be useful for individualizing protocols for clinical exercise testing.

Activities of Daily Living↗
PubMed1994

Intraoperative flow measurement of distal runoff: a valid predictor of outcome of infrainguinal bypass surgery.

OBJECTIVE: To assess the power of operative flow measurements in the prediction of outcome after infrainguinal bypass operations for critical ischaemia DESIGN: Open study SETTING: University department of vascular surgery SUBJECTS: 197 patients operated on for critical ischaemia between 1 January 1982 and 31 December 1989 under the care of one surgeon. INTERVENTIONS: Standard operative angiography and measurement of flow of distal runoff MAIN OUTCOME MEASURES: Patency and limb salvage RESULTS: All patients were followed up prospectively until 31 March 1991 or death. The estimated 5 year rates of primary patency and limb salvage were 0.75 and 0.86, respectively. Multivariate analysis showed that flow measurement was the most powerful predictor of graft patency (p = 0.0003) and limb salvage (p = 0.004) of all factors studied, including angiography. Irrespective of the site of distal anastomosis no polytetrafluoroethylene (PTFE) graft remained patent if the flow was less than 50 m/minute, whereas vein grafts remained patent if the flow was as little as 10 ml/minute. CONCLUSIONS: Flow is easy to measure and is a better predictor of outcome than angiography. Decisions about grafting should rely on flow measurements if there is any doubt about patency or limb salvage, particularly if a PTFE graft is going to be used.

Aged↗
PubMed1993

Intraoperative catheter thrombolysis as an adjunct to surgical revascularisation for infrainguinal limb-threatening ischaemia.

The objective of this study was to assess the benefits of intraoperative thrombolysis (IOL) on patients with acute leg ischaemia. This study was conducted in the Department of Cardiovascular Surgery, Inselspital, Berne, Switzerland. IOL was prospectively assessed in 25 patients with infrainguinal limb-threatening ischaemia due to acute thrombosis of atherosclerotic lesions and aneurysms (44%), occluded grafts (32%), arterial injuries (12%), delayed embolism (8%) and trash foot (8%). Three hundred and seventy-five thousand units of urokinase were delivered over 30 min with inflow occlusion to the profunda femoral artery in 8%, to the calf arteries via exposed trifurcation in 88% and to the pedal arch via exposed posterior tibial artery at the ankle in 8% of the patients. This was followed by graft thrombectomy in 24%, femoropopliteal bypass in 60%, intraoperative percutaneous transluminal angioplasty in 12% and vein patch angioplasty in 16%. Chief outcome measures were: postoperative morbidity; mortality; patency and limb salvage up to a maximum of 2 years. Postoperative bleeding complications occurred in two patients (8%) and consisted of two wound haematomas. Four patients died within 30 days after IOL, but no death could be attributed to IOL. All remaining patients were followed with a mean follow-up time of 10.9 months. The patency and limb salvage rate remained stable at 71 and 86% after 6 and 2 months, respectively. Conclusions were that IOL followed by surgical inflow restoration is a straightforward procedure for limb-threatening ischaemia with rewarding results regarding side effects, patency and limb salvage.

Acute Disease↗
PubMed1991

[Interventional angiography].

Percutaneous transluminal angioplasty (PTA) by balloon catheters is the standard method in interventional angiology. It is recommended in the aorto-iliac region for arterial stenoses, and in the femoro-popliteal arteries for stenoses and short occlusions. Due to progress in technology of catheters and guide wires, a primary success rate of more than 90% is to be expected with favorable angiographic conditions. The long-term patency rate of some 90% on the aorto-iliac level exceeds that of 70-90% on the femoro-popliteal level, with the patency rate decreasing with increasing complexity of the lesions. Subacute/acute occlusions of the femoro-popliteal arteries are treated successfully in 80% by catheter-thrombolysis and/or thrombus aspiration. Several new techniques are under clinical evaluation, such as laser angioplasty, rotational catheters, atherectomy catheters and stents. Their application in clinical routine has up to now not been justified except for special situations such as obtaining biopsy material by Simpson catheter or maintenance of patency in balloon resistant lesions by stents.

Angioplasty, Balloon↗
PubMed1991

[Choleperitoneum following Kehr's T-tube removal: conservative treatment with culdocentesis associated with sphincterotomy and endoscopic drainage of the bile ducts].

The Authors present a case of bile peritonitis due to a biliary fistula developed after T tube removal from the common bile duct. Highlighting poor clinical manifestations they report an alternative conservative treatment, by drainage of the bile leakage with culdocenthesis and successive endoscopic spincterotomy and transpapillary drainage.

Bile↗
PubMed1989

[Vascular endoprosthesis of femoro-popliteal occlusive disease].

A self-expanding vascular endoprosthesis (wall stent) was implanted in 26 patients with femoropopliteal occlusive disease following recurrent stenosis or occlusion after percutaneous angioplasty. Implantation was successful in all cases and there were no complications. Five of the 26 patients developed a thrombosis in the first nine days; in four of these, thrombolysis was successful. Patency rate after one month was 96%, after three months 95%, after six months 85% and after nine months 87%. In order to prevent thrombosis after implantation, anticoagulant therapy is indicated. Poor distal flow encourages intimal hyperplasia and therefore recurrences.

Adult↗
PubMed1984

Antibacterial activity of mare uterine fluid.

Luminal fluid from the mare uterus was used to investigate its relation to antibacterial defenses. Uterine flushings were collected at Day 3 of estrus, Day 8 postovulation and Day 15 postovulation. Uterine proteins were concentrated by ultrafiltration, dialyzed and examined for chemotactic activity to neutrophils and for antibacterial properties. Serum taken at the time of flushing was dialyzed and studied in a similar manner. Neutrophil migration in response to serum from Day 3 estrus and Day 8 postovulation was increased (P less than 0.05) above controls. Uterine protein from Day 8 postovulation and from Day 3 of estrus also stimulated neutrophil migration (P less than 0.05) above values of controls. Antibacterial activity was measured by incubation of S. zooepidemicus with concentrated uterine flushing or serum. Serum from all three estrous cycle intervals diluted 1:10 or used at a protein concentration equal to the protein concentration of uterine fluid did not inhibit growth. After 4 h of incubation, bacterial growth in estrous serum was significantly greater (P less than 0.01) than serum taken at Day 8 and Day 15 postovulation. Uterine flushings from Day 8 postovulation significantly decreased bacterial colony-forming units (P less than 0.01). Heating flushings at 56 degrees C for 30 min did not abolish the antimicrobial activity, while heating flushings for 30 min at 80 degrees C removed this activity. The antibacterial activity does not appear to be due to agglutinating antibody.

Animals↗
PubMed1982

Pirenzepine in duodenal ulcer. A six week, double-blind study.

Thirty-eight of forty patients satisfactorily concluded a double-blind, placebo-controlled trial to study the effects of pirenzepine (100 mg/day) on duodenal ulcers. After six weeks of treatment 14 of 18 patients (78%) in the pirenzepine-treated group and 7 of 20 patients (35%) in the placebo groups were healed. There was a statistically significant difference (P less than 0.05). The relief of day-time and night-time pain was significantly greater in the pirenzepine-treated group. Pirenzepine-treated patients consumed significantly fewer antacid tablets. The tolerability of pirenzepine was good. Pirenzepine (100 mg/day for six weeks) should be an effective and safe treatment for duodenal ulcers.

Adult↗