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R Baum

Publications and source records attributed to R Baum.

At least 19 recordsLinked to original sources
PubMed2003

[Initial status of patients and effects of rehabilitation after stroke--analysis of a patients' and a physicians' questionnaire in three neurological rehabilitation centres with a follow-up after 6 months].

Rehabilitation after stroke has to face specific problems when treating patients with more or less severe disabilities in cognition and communication. Correspondingly, stroke rehabilitation takes a special position within the larger field of rehabilitation, and relatively little is known outside the neurological scientific community about the status of patients at admission, the case mix in the centres and the short- and medium-term effects of rehabilitation. The present study describes in some detail the initial status in unselected samples of consecutive patients (n = 768) from three neurological rehabilitation centres. The description shows a very inconsistent picture in all centres, ranging from patients with no neurological deficits to patients needing intensive care. Across the centres, we found remarkable differences in case mix. In order to measure the effects of rehabilitation after stroke, an instrument was developed that combines a physicians' questionnaire aiming at an assessment of the severely disabled cases with a patients' questionnaire for the less severe cases for which the physicians' questionnaire would show "ceiling effects" so that improvements could no longer be depicted. The application of the instrument showed that about 50 % of the sample were not capable of answering the patients' questionnaire. For the patients with neurological deficits, the functional parameters of the physicians' questionnaire showed significant improvements at discharge that can be interpreted as "strong" effects (effect sizes 1.0-1.3). For the patients with less severe deficits (and usually in later stages of the rehabilitation process), the patients' questionnaire showed "strong" improvements on the somatic and psychosocial scales both at discharge and 6 months later. On the functional scales, however, only small improvements were found. Finally, predictors could be identified that explain a large amount of the variance for length of stay (R(2) =.42) as well as for the effects of rehabilitation (R(2) =.74). When comparing effects across rehabilitation units with differences of case mix, these predictors should be statistically controlled in order to assure fair comparisons.

Adult↗
PubMed2001

Endovascular repair of aortic aneurysms: critical events and adjunctive procedures.

OBJECTIVE: We sought to define the learning curve relative to the incidence and range of intraoperative problems and to establish guidelines for troubleshooting during the endovascular repair of infrarenal aortic aneurysms. METHODS: We prospectively evaluated our first 75 consecutive cases over a 12-month period and focused on perioperative critical events and adjunctive procedures as categorical outcome measures collected during the operation. Patients were separated into three groups on the basis of the date of their operation, such that group 1 consisted of our first 25 cases, group 2 our next 25 cases, and group 3 our last 25 cases. RESULTS: At least one critical event and adjunctive procedure marked 67 (89%) of 75 cases. In 51%, there were at least two critical events and adjunctive procedures. There were no immediate open conversions or intraoperative deaths. Access problems occurred in 28% of the 75 cases and were addressed by use of brachial-femoral artery access (30%), iliac artery/aortic bifurcation balloon angioplasty (8%), and iliofemoral conduits (4%). Graft foreshortening was the most common deployment event (44%), necessitating distal covered extensions. Iliac graft limb twists and kinks occurred in 12% of cases and were managed with balloon angioplasty and uncovered stents. General incidents included balloon ruptures (10%), arterial dissections (6%), iliac artery rupture (2.6%), and lower extremity ischemia (4%). The two cases of iliac artery rupture were managed with distal covered extensions, and there were no cases of atheroemboli. Intraoperative endoleaks were encountered in 44% of the cases and included proximal attachment sites (15%), distal attachment sites (9%), type 2 sources, and "blushes." Management of intraoperative endoleaks included proximal/distal covered extensions and re-ballooning. Our 30-day endoleak rate was 20%. The incidence of critical events did not decrease in the latter one third compared with the first two thirds of cases. CONCLUSIONS: Critical events occur frequently during endovascular repair of aortic aneurysms. The intraoperative problems range from the common endoleaks, access and deployment issues, and balloon ruptures, to rare but life-threatening complications such as iliac artery rupture. A toolbox of accessories that includes wires, catheters, large balloons, covered proximal and distal extensions, and uncovered stents is essential given the frequency of adjunctive procedures. Successful aortic endografting requires more than mere familiarity with basic endovascular techniques.

Aortic Aneurysm↗
PubMed2000

Charged-particle multiplicity near midrapidity in central Au+Au collisions at sqrt[SNN]=56 and 130 GeV.

We present the first measurement of pseudorapidity densities of primary charged particles near midrapidity in Au+Au collisions at sqrt[s(NN)] = 56 and 130 GeV. For the most central collisions, we find the charged-particle pseudorapidity density to be dN/deta|(|eta|<1) = 408+/-12(stat)+/-30(syst) at 56 GeV and 555+/-12(stat)+/-35(syst) at 130 GeV, values that are higher than any previously observed in nuclear collisions. Compared to proton-antiproton collisions, our data show an increase in the pseudorapidity density per participant by more than 40% at the higher energy.

Journal Article↗
PubMed1999

Measurement of clinical and subclinical tumour response using [18F]-fluorodeoxyglucose and positron emission tomography: review and 1999 EORTC recommendations. European Organization for Research and Treatment of Cancer (EORTC) PET Study Group.

[18F]-fluorodeoxyglucose ([18F]-FDG) uptake is enhanced in most malignant tumours which in turn can be measured using positron emission tomography (PET). A number of small clinical trials have indicated that quantification of the change in tumour [18F]-FDG uptake may provide an early, sensitive, pharmacodynamic marker of the tumoricidal effect of anticancer drugs. This may allow for the introduction of subclinical response for anticancer drug evaluation in early clinical trials and improvements in patient management. For comparison of results from smaller clinical trials and larger-scale multicentre trials a consensus is desirable for: (i) common measurement criteria; and (ii) reporting of alterations in [18F]-FDG uptake with treatment. This paper summarises the current status of the technique and recommendations on the measurement of [18F]-FDG uptake for tumour response monitoring from a consensus meeting of the European Organization for Research and Treatment of Cancer (EORTC) PET study group held in Brussels in February 1998 and confirmed at a subsequent meeting in March 1999.

Antineoplastic Agents↗
PubMed1998

Radioimmunoscintigraphy of recurrent, metastatic, or occult colorectal cancer with technetium Tc 99m 88BV59H21-2V67-66 (HumaSPECT-Tc), a totally human monoclonal antibody. Patient management benefit from a phase III multicenter study.

PURPOSE: The study contained herein was undertaken to evaluate the accuracy of radiolabeled human monoclonal antibody, 88BV59H21-2V67-66 (88BV59 or HumaSPECT-Tc), in predicting disease resectability in presurgical subjects with recurrent, metastatic, or occult colorectal carcinoma. METHODS: A total of 219 patients with disease visualized on computed tomographic scan (recurrent or metastatic disease) or with negative or equivocal computed tomographic scan and rising carcinoembryonic antigen serum levels (occult group) received technetium Tc99m-labeled 88BV59 intravenously. Planar and single photon emission computed tomograhic images were obtained 14 to 20 hours postinfusion, before surgery. The ability of computed tomographic and HumaSPECT-Tc imaging to define the extent of disease and to predict resectability was evaluated based on surgical and histopathologic results. RESULTS: In patients with recurrent or metastatic disease (170 evaluable patients), the accuracy of predicting nonresectability of disease was significantly greater (P < 0.001) for HumaSPECT-Tc than for computed tomography (60 vs 29 percent). Computed tomography understaged 41 percent of patients believed to have resectable disease compared with 27 percent for HumaSPECT-Tc (P < 0.001). In occult disease patients (29 computed tomographic and 28 HumaSPECT-Tc evaluable patients), the overall accuracy of predicting resectability/nonresectability was 6 percent for HumaSPECT-Tc compared with 24 percent from computed tomography. Administration of HumaSPECT-Tc had no effect on monoclonal antibody-based in vitro diagnostic assays. Only a single patient demonstrated an anti-antibody response (90 ng/ml) at nine weeks postinfusion. CONCLUSION: HumaSPECT-Tc was more accurate than computed tomography in determining disease resectability in patients with metastatic, recurrent, or occult cancer. The addition of HumaSPECT-Tc imaging can play a significant role in patient management decisions.

Adult↗
PubMed1998

Limited value of fluorine-18 fluorodeoxyglucose positron emission tomography for the imaging of neuroendocrine tumours.

Scintigraphy using [111In-DTPA-d-Phe1]-pentetreotide or pentavalent technetium-99m-dimercaptosuccinic acid [99mTc(V)-DMSA] has been shown to localize well-differentiated and slowly growing neuroendocrine tumours, whereas increased fluorodeoxyglucose (FDG) uptake is associated with malignancy. The aim of this study was to compare the value of fluorine-18 FDG positron emission tomography (PET) with that of somatostatin receptor scintigraphy (SS-R) and dual-radionuclide scintigraphy [SS-R and 99mTc(V)-DMSA = DNS] in detecting malignant neuroendocrine tumours. Fifteen patients with metastasizing gastroenteropancreatic tumours (GEP tumours; n = 7), medullary thyroid carcinomas (MTCs; n = 8) and elevated tumour markers [GEP tumours: 5-hydroxyindoleacetic acid, insulin; MTCs: calcitonin, carcinoembryonic antigen (CEA)] were studied. Prior to PET, all patients with GEP tumours underwent SS-R. DNS was performed in all patients with MTC. Patients had been fasting for at least 12 h and normal glucose plasma levels were confirmed. Sixty minutes after intravenous administration of 18F-FDG (mean: 374 MBq) whole-body PET and regional scans were performed. In addition, the resected tissues were prepared for immunocytochemistry examination (cell cycle-associated Ki-67 antigen). In two patients with less-differentiated GEP tumours associated with high proliferative activity and increased FDG uptake, SS-R failed to detect any lesion. In comparison, in four patients with well-differentiated GEP tumours showing low proliferative activity, SS-R localized four primary tumours, 22 lymph node metastases and 18 malignant liver lesions, whereas 18F-FDG PET demonstrated normal distribution. In one patient with a metastasizing carcinoid (medium proliferative activity) SS-R localized multiple metastases, whereas PET demonstrated low FDG uptake in all known metastases. In patients with recurrent MTC and rapidly increasing CEA levels DNS detected only three lesions in two patients, whereas PET demonstrated one pulmonary, three osseous, 20 mediastinal, ten locoregional, and four liver metastases in seven patients. Twenty-nine malignant lesions were confirmed by follow-up and nine lymph node metastases could be surgically removed. In conclusion, PET imaging of gastroenteropancreatic tumours revealed increased glucose metabolism only in less-differentiated GEP tumours with high proliferative activity and metastasizing MTC associated with rapidly increasing CEA levels. Therefore, additional 18F-FDG PET should be performed only if SS-R or DNS is negative.

Adult↗
PubMed1998

Radioimmunoscintigraphy of recurrent, metastatic, or occult colorectal cancer with technetium 99m-labeled totally human monoclonal antibody 88BV59: results of pivotal, phase III multicenter studies.

PURPOSE: To assess the performance and potential clinical impact of a totally human monoclonal antibody, 88BV59 (HumaSPECT) (INTRACEL, Corp, Rockville, MD), in 202 assessable presurgical patients with recurrent, metastatic, or occult colorectal cancer. METHODS: 88BV59, labeled with technetium Tc 99m (99mTc) (HumaSPECT-Tc), was injected intravenously, and planar and single photon emission tomography (SPECT) images were obtained 14 to 20 hours postinjection. Surgical and pathologic verification of tumor were used as the standard against which the performance of HumaSPECT-Tc imaging and computed tomography (CT) analysis were evaluated. RESULTS: All patients entered onto the recurrent disease study had at least one tumor site defined on CT. The sensitivity of HumaSPECT-Tc in those CT-positive patients was 87%. The specificity of HumaSPECT-Tc was 57% compared with 17% for CT and the difference was statistically significant (P < .001). The diagnostic information provided by HumaSPECT-Tc significantly (P < .001) improved the accuracy of the identification of resectable and nonresectable disease over that of CT (80% v 62%). HumaSPECT-Tc scans resulted in a significant (P < .001) reduction versus CT in terms of the proportion of patients understaged (27% v 41%) and overstaged (4% v 26%). In patients with occult disease (increasing carcinoembryonic antigen [CEA] titer, negative diagnostic work-up, negative CT), HumaSPECT-Tc correctly identified disease in 15 of 22 (68%) patients. HumaSPECT-Tc images provided additional clinical data that would have affected patient management decisions in 40 of 202 (19.8%) patients. In 365 patients who received 88BV59, only a single detectable human anti-human antibody (HAHA) response (90 ng/mL) at 9 weeks postinfusion was observed. CONCLUSION: HumaSPECT-Tc can provide important and accurate information about the presence and location of disease in patients with a high clinical suspicion of metastatic or recurrent colorectal cancer and either positive (known disease) or negative (occult disease) CT scans.

Adult↗
PubMed1992

Magnetic resonance angiography of the pelvis and lower extremities. Works in progress.

Two-dimensional time-of-flight (TOF) magnetic resonance angiography (MRA) of the lower extremities has recently been rediscovered as a technique that can be used to find small vessels in the foot and leg for surgical revascularization in patients with severe peripheral vascular disease. The purpose of this article is to acquaint the reader with some of the common problems that may be encountered in this imaging technique and to show their derivations and solutions were applicable. In addition, the authors show receiver operator curve analysis of one radiologist's ability to determine the location and patency of arteries using this technique to be outstanding (AZ, 0.9737). This represents a promising new technique for imaging the arterial system in patients with severe peripheral vascular disease.

Blood Vessels↗
PubMed1991

Comparison of 99Tcm-labelled monoclonal anti-granulocyte antibody and 111In-labelled IgG for the detection of focal sites of infection in rats.

The abilities of 99Tcm-labelled monoclonal anti-human granulocyte antibody (AGAb) and 111In-labelled nonspecific polyclonal human immunoglobulin (IgG) to localize at focal sites of inflammation were compared in rats with deep thigh infection due to E. coli. The radiolabelled antibodies were coadministered followed 4-6 and 24 h later by imaging and biodistribution studies. At 4-6 h after injection, the target to background ratio (T/B, lesion to contralateral leg) and percentage residual activity (% RA, counts in the lesion/total body counts) were nearly identical for both antibody preparations. At 24 h, T/B and % RA increased significantly (P less than 0.001) for both proteins but differences between the agents were not significant. In vitro analysis of the binding of AGAb and human polyclonal IgG to rat granulocytes showed a low level of binding with both agents. These results suggest that the primary mechanism of localization, by either antibody preparation in this model, is not antigen related. 111In-labelled nonspecific human IgG and 99Tcm-AGAb are equivalent reagents for the detection of focal sites of infection in the rat.

Animals↗
PubMed1989

[Cytogenetic, endocrinological and immunological studies of tissue cultures from ectopic pregnancies].

The world-wide increase in extrauterine pregnancies induced us to grow trophoblastic elements obtained from ectopic locations in tissue cultures in order to determine whether the tubal implantation of the blastocyst could be caused by chromosomal aberrations. In addition, we investigated for what period of time trophoblastic tissue from ectopic sites is capable of producing HCG in culture. This was done in view of an eventual use of this method as a model for the testing of the effect of antitrophoblastic agents in vitro. Finally, the concentration of several tumor markers in the culture medium was measured. The karyotype could be determined in 16 out of 20 tissue specimen subjected to tissue culture; in one case a chromosomal aberration was recognized, two times there was evidence of increased fragility of the chromosomes. The ratio of female to male karyotypes was 10 to 6. HCG was found to be produced for 6 to 9 days in the tissue cultures. The concentration of the tumor markers CEA, CA 19-9, CA 12-5 and CA 15-3 in the culture medium was low as compared to cultures containing additional tubal mucosa. We are concluding that chromosomal aberrations do not seem to play a causal role in the genesis of EUP. The assay of HCG production by trophoblastic cells in tissue cultures could eventually be used for the testing of agents which might ultimately be employed for the non-surgical treatment of certain cases of EUP.

Biomarkers, Tumor↗
PubMed1988

Ultrasonographic findings with bleeding and nonbleeding esophageal varices.

Real time ultrasonography was carried out in 49 cirrhotic patients within 10 days of esophagoscopy, and in 20 normal subjects. Among the cirrhotic patients, 42 had varices and 18 of these had hematemesis within 3 months of study. The varices were graded 0 to 4+ endoscopically; the diameter of the portal vein, the splenic vein, the hepatic artery, and the maximal length of the spleen were determined on ultrasound. In addition, portal collateral veins and the sudden amputation of portal vein branches in the liver were identified when present. There was a significant correlation of the diameter of the portal vein and the maximal spleen length with the magnitude of varices on endoscopy; there was no significant relationship between the splenic vein or the hepatic artery diameter. Less than half the patients with varices had sonographically demonstrated collaterals or portal vein branch amputation. A sonoscore was derived allotting one point each for enlarged portal vein (greater than 1.3 cm), enlarged spleen, collaterals or two or more amputated veins. The sonoscore correlated better with the endoscopic grade of varices than any other marker. The sonoscore among the patients with varices who bled was significantly higher (p less than 0.01) than any of the other measures. It is concluded that real time ultrasound can be used to screen for varices and to identify the need for endoscopy.

Collateral Circulation↗
PubMed1986

[Effect of captopril in chronic aortic insufficiency].

In 16 patients with chronic aortic regurgitation, we studied the acute hormonal and hemodynamic effects of 12.5 to 25 mg captopril; in 12 patients the changes after a 4 to 8 week treatment period (mean 6.3 +/- 2 weeks; doses: 3 times 12.5 to 3 times 25 mg/day) were investigated. The following baseline variables were evaluated: the radionuclide left ventricular ejection fraction (EF) at rest and during exercise, left ventricular end-diastolic volume (EDV), regurgitant blood volume (RBV); and plasma renin activity (PRA). Repeated determinations of EF, EDV and RPA were carried out 90 minutes after application of the drug. In patients with chronic therapy, EF at rest and during exercise, EDV, RBV and PRA were reinvestigated at the end of the study. Acute administration of captopril was followed by an increase of EF (from 49 +/- 12 to 55 +/- 12%, p less than 0.001) and a slight decrease of EDV (from 389 +/- 160 to 376 +/- 146 ml, p less than 0.05). PRA significantly increased (from 1.6 to 3.1 ng/ml/h, p less than 0.05). Chronic therapy resulted in a moderate decrease of systolic and diastolic blood pressure (from 156/70 +/- 31/15 to 140/63 +/- 23/15 mm Hg, p less than 0.01). However, no significant changes were observed in EF at rest and during exercise (51 +/- 9 vs. 53 +/- 10% and 45 +/- 14 vs. 47 +/- 14%), EDV (433 +/- 179 vs. 422 +/- 179 ml) and RBV (136 +/- 81 vs. 129 +/- 77 ml). PRA was significantly increased (6.3 ng/ml/h, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve Insufficiency↗
PubMed1986

[Persisting volume overload of the left ventricle following surgical correction of chronic aortic insufficiency].

After aortic valve replacement for chronic aortic regurgitation, complete normalization of the left ventricular end-diastolic volume can rarely be observed. We therefore investigated the role of continual volume overload caused by persisting concomitant mitral regurgitation. 20 patients who received an aortic valve for chronic aortic regurgitation (group 1), 5 patients after operation for aortic stenosis (group 2) and 6 patients with double valve replacement because of aortic and mitral valve lesions were included in the study 1 to 108 months after operation. All patients were examined clinically and by combined first pass/equilibrium radionuclide ventriculography. In the case of significant regurgitation (greater than 20%) 2-dimensional colour-coded Doppler-echocardiography was performed in patients of group 1 to localize the regurgitant lesion. 15 patients of group 1 had a typical systolic murmur indicating mitral regurgitation. 14 of these patients had significant scintigraphic left-sided heart regurgitation: 7 patients had regurgitant fractions between 21 and 40%; 6 patients between 41 and 60%; in 1 patient RF was 64%. Echocardiography confirmed mitral regurgitation in 9 of 11 of these cases. No significant regurgitation was observed in patients of group 2; mild regurgitation was measured in 5 of 6 patients of group 3 (26 to 31%). We conclude that in patients with chronic aortic regurgitation complete normalization of the left ventricular end-diastolic volume after valve replacement may not occur in some patients because of persisting mitral regurgitation.

Aortic Valve Insufficiency↗