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At least 955 records · Page 53Linked to original sources
PubMed1996

PTCA with the use of cardiac assist devices: risk stratification, short- and long-term results.

Percutaneous cardiopulmonary assist devices (PCPS) have become available in interventional cardiology within recent years. These tools offer the opportunity of performing percutaneous transluminal coronary angioplasty (PTCA) in high-risk patients characterized by significant stenoses of several coronary arteries and a poor left ventricular function. It is unclear for which patients PCPS are necessary and which patients will profit by PTCA as compared to coronary artery bypass grafting (CABG). Therefore, the anticipated risk of CABG and of PTCA without assist devices was calculated according to risk scores and compared with our results of assisted PTCA. In addition the long-term survival rate was investigated. In 35 patients (mean 65.5 years of age, 12 females, 23 males), we performed PTCA concomitant with the use of cardiac assist devices. The indications for the use of a cardiac assist device were severely impaired LV function (EF 30% +/- 8.9%) in combination with significant coronary artery disease (2.7 +/- 0.3 vessels) and a significant supply area of the vessel to be dilated. In 6 patients, PCPS was started before coronary angioplasty because of hemodynamic instability. In 21 cases, PCPS was on a standby basis without being connected to the patient's circulation. In 8 patients, a left heart assist device, the 14F-Hemopump, was inserted percutaneously. The patients were analyzed using risk scores of angioplasty and of coronary bypass graft surgery. The calculated risk of hemodynamic compromise during PTCA according to the risk scores was more than 50%. The anticipated risk of a fatal outcome following CABG would have been 19.8%. PTCA was performed on an average of 2.0 coronary arteries per patient and was successful in 85%. We observed a decline in angina pectoris classification (CCS) from 3.5 to 1.6. An average reduction of 1.1 NYHA class was achieved. The in-hospital mortality was 8.6% (3 patients: 1 x sepsis, 1 x early reocclusion, 1 x cerebral embolism). At 24 months follow-up, a re-PTCA was necessary in four cases because of restenosis. In the remainder, NYHA and CCS class were stable during the follow-up period. An additional five patients died during the first year and two patients in the second year. We conclude that PTCA with the use of a cardiac assist device shows favorable short-term results in a subset of patients with extended coronary artery disease and severely impaired LV function who are not suitable for nonsupported PTCA or CABG due to their risk profile. However, the long term results are not satisfying and stress the need for complete revascularisation with CABG once the patient's condition is stabilized by means of supported PTCA.

Aged↗
PubMed1983

Stratification of risk factors in renal cell carcinoma.

One hundred fifteen patients underwent surgical treatment of renal cell carcinoma. Survival time was analyzed by statistical regression methods in order to determine the joint significance of stage, using both the Robson and TNM classifications, histologic grade, cell type, and demographic features of the patient sample. Grade and cell type were essentially interchangeable with respect to predicting survival in patients with and without metastatic disease. The strong association between these two factors explains and supports this result. The presence of metastases dramatically altered survival. Local extent of the tumor was an important indicator of survival in the nonmetastatic group of patients, but was not a statistically significant factor in those patients presenting with widespread disease. Venous involvement was not found to be of prognostic significance in either group. Age and weight loss contributed to predicting survival in the nonmetastatic patient group in addition to the measures of disease extent already discussed. Sex and race were not significant indicators of length of survival. In the group of patients with metastatic disease, no difference in survival was observed between soft tissue and bony metastases.

Adenocarcinoma↗
PubMed1988

Stratification of patients with metastatic prostate cancer based on extent of disease on initial bone scan.

Most patients with metastatic prostate cancer will have metastasis to bone. Such patients are best monitored by serial radionuclide bone scans. One hundred sixty six men with bone metastasis from prostate cancer who received androgen deprivation therapy had their pretreatment bone scans reviewed using a semiquantitative grading system based upon the extent of disease (EOD) observed on the scan. The EOD on the scan correlated with survival. The 2-year survival rates for EOD I to IV were 94%, 74%, 68%, and 40%, respectively. The survival of patients in categories EOD I and IV significantly differed from the other categories. Men with metastatic prostate cancer entered into trials designed to evaluate the impact of treatment on survival should be stratified based upon the EOD on the bone scan. This analysis also indicates that patients in the EOD IV category have a particularly poor prognosis and may be candidates for alternative treatments.

Bone Neoplasms↗
PubMed1991

Neoadjuvant chemotherapy consisting of cisplatin and continuous infusions of bleomycin and 5-fluorouracil for advanced head and neck cancer. The need for a new stratification for stage IV (M0) disease.

A Phase II study of cisplatin (100 mg/m2 on day 1) and bleomycin (15 mg intravenous push day 1) followed by 5 days of continuous intravenous infusions of 5-fluorouracil (5-FU) (650 mg/m2/d) and bleomycin (16 mg/m2/d) repeated at 21-day intervals was performed in 54 previously untreated patients with nonmetastatic (M0), locoregionally advanced head and neck squamous cell carcinoma (SCC). The aim of this study was to increase the complete response rate to chemotherapy and to identify prognostic factors that may influence local control and disease-free survival. From April 1986 until August 1988, 5 patients with Stage III and 49 with Stage IV (International Union Against Cancer-American Joint Committee on Cancer 1986 [UICC-AJCC]) disease received this regimen. Thirty (61%) patients with Stage IV disease had bulky nodal disease (9 N2c and 21 N3) and 29 (53%) had T4 primary lesions. The response rate was 59% (95% confidence interval, 47% to 71%) and the complete response rate to chemotherapy was 13% (95% confidence interval, 0% to 26%). The response rate was greatly influenced by tumoral volume and performance status (PS). The complete response rate to chemotherapy was 40% for patients with Stage III disease (2 of 5 patients) versus 10% for patients with Stage IV disease (5 of 49 patients; P = 0.02). The response rate for patients with Stage III disease was 100% (5 of 5 patients) versus 55% for patients with Stage IV disease (27 of 49 patients; P = 0.14). For patients with Stage IV bulky nodal disease (N2c-N3), the response rate was 43% (13 of 30 patients) and the complete response rate to chemotherapy was 3% (1 of 30 patients) versus 68% (13 of 19 patients; P = 0.13) and 21% (4 of 19 patients; P = 0.07), respectively, for patients with Stage IV less than N2b disease. The local control rate after definitive therapy was 100% for patients with Stage III disease, 70% (17 of 24 patients) for patients with Stage IV less than N2b disease, and 17% (5 of 30 patients) for patients with bulky nodal disease (P = 0.0005). As of February 1991, with a median follow-up time of 38 months (range, 30 to 53 months), 4 of 5 patients with Stage III disease and 7 of 19 patients with Stage IV less than N2b disease were alive with no evidence of disease (37%) versus 0 of 30 patients with bulky nodal disease (P = 0.001).(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1992

Significance of a new stratification of alkaline phosphatase and extent of disease in patients with prostate carcinoma with bone metastasis.

Bone is the most frequent site of metastatic prostate cancer and the prognosis of patients with bone metastasis is poor. The authors have investigated a semiquantitative system to evaluate bone metastatic lesions in terms of cancer-specific survival. Based on the extension of disease (EOD) grade proposed by Soloway and associates, a new EOD grading system obtained from bone scintigraphy alone and EOD score obtained from bone scintigraphy and alkaline phosphatase was studied in 164 patients with prostate cancer with metastatic bone involvement. In terms of a cancer-specific survival and prostate cancer death, both the new EOD grade and the EOD score were apparently superior to eight other items studied (age, medical score, gait disturbance, histologic grade, erythrocyte sedimentation rate, prostatic acid phosphatase, and alkaline phosphatase). Multivariate analysis revealed that the EOD score was better than the new EOD grade. This improvement was due to the elimination of false-positive or nonactive metastatic bone lesions on bone scintigraphy through the alkaline phosphatase evaluation.

Aged↗
PubMed1993

Stratification of pathologic features in radical prostatectomy specimens that are predictive of elevated initial postoperative serum prostate-specific antigen levels.

BACKGROUND: Prostate-specific antigen (PSA) is an important marker for adenocarcinoma of the prostate and is of clinical utility in assessment of residual carcinoma after radical prostatectomy. Although elevated postoperative serum PSA levels have been linked to pathologic stage in radical prostatectomy specimens, limited data are available on the relationship of postoperative PSA levels to margin positivity, intraglandular tumor extent, and histologic grade. METHODS: Initial postoperative serum PSA levels were related to pathologic features of 90 radical prostatectomy specimens with adenocarcinoma of the prostate. Logistic regression analysis was used to stratify pathologic stage, percentage intraglandular carcinoma, histologic grade, and margin positivity as predictors of elevated initial postoperative PSA levels. RESULTS: Pathologic stage, percentage carcinoma, and margin positivity were nearly equivalent in strength of prediction, whereas Gleason histologic grade was a significant but less reliable predictor of elevated initial postoperative PSA levels. Thirty-one of 51 (60.8%) patients with extension of carcinoma outside the prostate gland had an elevated initial postoperative PSA level, whereas only 5 of 39 (12.8%) patients with organ-confined carcinoma had an elevated postoperative PSA level. Intraglandular tumor extent greater than 10% was associated with a greater likelihood of an elevated postoperative PSA level. Additional predictive capacity was obtained with concurrent use of pathologic stage and percentage carcinoma or margin positivity in multivariate analysis. CONCLUSIONS: In radical prostatectomy specimens, pathologic stage, intraglandular carcinoma extent, and margin positivity are particularly important morphologic parameters because they are predictive of residual carcinoma that is detected early, as judged by an elevated initial postoperative serum PSA level.

Adenocarcinoma↗
PubMed2000

Radial stratification of ions as a function of mass to charge ratio in collisional cooling radio frequency multipoles used as ion guides or ion traps.

Collisional cooling in radio frequency (RF) ion guides has been used in mass spectrometry as an intermediate step during the transport of ions from high pressure regions of an ion source into high vacuum regions of a mass analyzer. Such collisional cooling devices are also increasingly used as 'linear', two-dimensional (2D) ion traps for ion storage and accumulation to achieve improved sensitivity and dynamic range. We have used the effective potential approach to study m/z dependent distribution of ions in the devices. Relationships obtained for the ideal 2D multipole demonstrate that after cooling the ion cloud forms concentric cylindrical layers, each of them composed of ions having the same m/z ratio; the higher the m/z, the larger is the radial position occupied by the ions. This behavior results from the fact that the effective RF focusing is stronger for ions of lower m/z, pushing these ions closer to the axis. Radial boundaries of the layers are more distinct for multiply charged ions, compared to singly charged ions having the same m/z and charge density. In the case of sufficiently high ion density and low ion kinetic energy, we show that each m/z layer is separated from its nearest neighbor by a radial gap of low ion density. The radial gaps of low ion population between the layers are formed due to the space charge repulsion. Conditions for establishing the m/z stratified structure include sufficiently high charge density and adequate collisional relaxation. These conditions are likely to occur in collisional RF multipoles operated as ion guides or 2D ion traps for external ion accumulation. When linear ion density increases, the maximum ion cloud radius also increases, and outer layers of high m/z ions approach the multipole rods and may be ejected. This 'overfilling' of the multipole capacity results in a strong discrimination against high m/z ions. A relationship is reported for the maximum linear ion density of a multipole that is not overfilled.

Algorithms↗
PubMed2001

Stratification of flare intensity identifies placebo responders in a treatment efficacy trial of patients with osteoarthritis.

OBJECTIVE: Studies evaluating osteoarthritis treatment often use increased arthritis activity ("flare") as a selection criterion, although no standardized assessments are available to quantify flare intensity and little is known about how this criterion affects treatment comparisons. This study evaluated the reliability of a flare assessment and how pretreatment flare intensity impacts conclusions on treatment efficacy. METHODS: Using data from a double-blind, randomized, controlled trial (n = 182), we compared 3 osteoarthritis treatments with placebo in patients who met 3 of 4 flare criteria. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire was used to document levels of pain, stiffness, and physical functioning at baseline and at the final visit. Following factor analytic evaluation, the flare items were standardized and summed to create a flare intensity index, which was used to identify patient subgroups. Analysis of covariance was applied to compare change in WOMAC scale scores from baseline to final visit for assessment of treatment differences among the flare intensity subgroups. RESULTS: The flare indicators appeared unidimensional. Analyses were stratified by tertiles of flare intensity. Mean WOMAC scores improved in the patients receiving active treatment who were categorized into the 2 lowest flare intensity subgroups, but mean WOMAC scores improved in patients in all 4 treatment groups (active and placebo) in the most intense flare subgroup. CONCLUSION: Patients with higher intensity flares may be more likely to report substantial improvement in functional status regardless of treatment. Failure to account for flare intensity in analyses of data from pain trials with flare-based designs may inflate the risk of Type I and Type II errors in the interpretation of study results.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2005

Promotor genotype of the platelet-derived growth factor receptor-alpha gene shows population stratification but not association with spina bifida meningomyelocele.

Neural tube defects (NTDs) constitute a major group of congenital malformations with an overall incidence of approximately 1-2 in 1,000 live births in the United States. Hispanic Americans have a 2.5 times higher risk than the Caucasian population. Spina bifida meningomyelocele (SBMM) is a major clinical presentation of NTDs resulting from lack of closure of the spinal cord caudal to the head. In a previous study of spina bifida (SB) patients of European Caucasian descent, it was suggested that specific haplotypes of the platelet-derived growth factor receptor-alpha (PDGFRA) gene P1 promoter strongly affected the rate of NTD genesis. In our study, we evaluated the association of PDGFRA P1 in a group of 407 parent-child triads (167 Caucasian, 240 Hispanics) and 164 unrelated controls (89 Caucasian, 75 Hispanic). To fully evaluate the association of PDGFRA P1, we performed both transmission-disequilibrium test (TDT) and association analyses to test the hypotheses that PDGFRA P1 was (1) transmitted preferentially in SBMM affected children and (2) associated with the condition of SBMM comparing affected children to unaffected controls. We did find that there was a different allelic and genotypic distribution of PDGFRA P1 when comparing Hispanics and Caucasians. However, neither ethnic group showed strong association between SBMM and the PDGFRA P1 region. These findings suggest that PDGFRA P1 does not have a major role in the development of SBMM.

Adult↗
PubMed2002

Stratification of pedigrees multiplex for systemic lupus erythematosus and for self-reported rheumatoid arthritis detects a systemic lupus erythematosus susceptibility gene (SLER1) at 5p15.3.

OBJECTIVE: Arthritis is a common manifestation in systemic lupus erythematosus (SLE), appearing in approximately 85% of patients. Often, the polyarthritis at presentation of SLE cannot be distinguished from rheumatoid arthritis (RA) by physical examination or history. Indeed, physicians initially tell many SLE patients that they have RA (one source of "self-reported RA"), only to have SLE established later. In addition, RA aggregates in families with an SLE proband. We predicted that pedigrees multiplex for both SLE and for self-reported RA would better isolate particular genetic effects. If this proved to be true, we would then use the increased genetic homogeneity to more easily reveal genetic linkage. METHODS: From a collection of 160 pedigrees multiplex for SLE, we selected 36 pedigrees that also contained >or=2 members with self-reported RA (19 pedigrees were African American, 14 were European American, and 3 were of other ethnic origin). Data from a genome scan of 307 microsatellite markers were evaluated for SLE linkage by contemporary genetic epidemiologic techniques. RESULTS: The most significant evidence of linkage to SLE was obtained at 5p15.3 in the European American pedigrees by both parametric (logarithm of odds [LOD] score 6.2, P = 9.3 x 10(-8)) and nonparametric (LOD score 6.9, P = 1.7 x 10(-8)) methods. The best-fitting model for this putative SLE gene in this region was a recessive gene with a population frequency of 5% and with 50% penetrance in females and 15% penetrance in males at virtually 100% homogeneity. CONCLUSION: For a genetically complex disease phenotype, an unusually powerful linkage has been found with SLE at 5p15.3 in European American pedigrees multiplex for SLE and for self-reported RA. This result predicts the presence of a gene at the top of chromosome 5 in this subset of patients that is important for the pathogenesis of SLE.

Arthritis, Rheumatoid↗